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King Ferry is a hamlet in the town of Genoa, Cayuga County, New York, United States. The community is located at the intersection of New York State Route 90 and New York State Route 34B, north of Ithaca. King Ferry has a post office with ZIP code 13081, which opened on December 15, 1807.
References
Hamlets in Cayuga County, New York
Hamlets in New York (state) | wiki |
Christianity and Islam are the two largest religions in the world, with 2.8 billion and 1.9 billion adherents, respectively. Both religions are considered as Abrahamic, and are monotheistic, originating in the Middle East.
Christianity developed out of Second Temple Judaism in the 1st century CE. It is founded on the life, teachings, death, and resurrection of Jesus Christ, and those who follow it are called Christians. Islam developed in the 7th century CE. Islam is founded on the teachings of Muhammad, as an expression of surrender to the will of God. Those who follow it are called Muslims which means "submitter to God".
Muslims view Christians to be People of the Book, and also regard them as kafirs (unbelievers) committing shirk (polytheism) because of the Trinity, and thus, contend that they must be dhimmis (religious taxpayers) under Sharia law. Christians similarly possess a wide range of views about Islam. The majority of Christians view Islam as a false religion due to the fact that its adherents reject the Trinity, the divinity of Christ, the Crucifixion and Resurrection of Christ.
Islam considers Jesus to be the al-Masih (Arabic for Messiah) who was sent to guide the Banī Isrā'īl (Arabic for Children of Israel) with a new revelation: al-Injīl (Arabic for "the Gospel"). Christianity also believes Jesus to be the Messiah prophesied in the Hebrew scriptures. However, far more central to the Christian faith is that Jesus is the incarnated God, specifically, one of the hypostases of the Triune God, God the Son. Belief in Jesus is a fundamental part of both Christian and Islamic theology.
Christianity and Islam have different sacred scriptures. The sacred text of Christianity is the Bible while the sacred text of Islam is the Quran. Muslims believe that al-Injīl was distorted or altered to form the Christian New Testament. Christians, on the contrary, do not have a univocal understanding of the Quran, though most believe that it is fabricated or apocryphal work. There are similarities in both texts, such as accounts of the life and works of Jesus and the virgin birth of Jesus through Mary; yet still, some Biblical and Quranic accounts of these events differ.
Similarities and differences
In the Islamic tradition, Christians, as well as, Jews, are believed to worship the same God that Muslims worship. However, to some, there are many different opinions in the discussion of whether Muslims and Christians worship the same God. A greater problem is that "worships x" is what analytic philosophers, like Peter van Inwage, a leading professor in the philosophy of religion, label an "intensional (as opposed to extensional) context", where the term "x" does not have to refer to anything at all (as in, e.g., "Jason worships Zeus"). In an "intensional context" co-referring terms cannot be replaced without affecting the truth value of the statement. For instance, even though "Jupiter" may refer to the same entity as "Zeus", still Jason, a Greek, does not worship Jupiter and may not even be aware of the Roman deity. So it cannot be said that "Abdul," a Muslim, worships Yahweh, even if Yahweh and Allah are co-referring names.
Scriptures
The Christian Bible is made up of the Old Testament and the New Testament. The Old Testament was written over a period of two millennia prior to the birth of Christ. The New Testament was written in the decades following the death of Christ. Historically, Christians universally believed that the entire Bible was the divinely inspired Word of God. However, the rise of higher criticism during the Enlightenment has led to a diversity of views concerning the authority and inerrancy of the Bible in different denominations. Christians consider the Quran to be a non-divine set of texts.
The Quran dates from the early 7th century, or decades thereafter. Muslims believe it was revealed to Muhammad, gradually over a period of approximately 23 years, beginning on 22 December 609, when Muhammad was 40, and concluding in 632, the year of his death. The Quran assumes familiarity with major narratives recounted in the Jewish and Christian scriptures. It summarizes some, dwells at length on others and differs in others. Muslims believe that Jesus was given the Injil (Greek evangel, or Gospel) by Allah and that parts of these teachings were lost or distorted (tahrif) to produce the Hebrew Bible and the Christian New Testament. The majority of Muslims consider the Quran to be the only revealed book that has been protected by God from distortion or corruption, being remained unchanged and unedited since the death of Muhammad, though scholars and early Islamic sources reject this traditionalist view.
Jesus
Muslims and Christians both believe that Jesus was born to Mary, a virgin. They both also believe that Jesus is the Messiah. However, they differ on other key issues regarding Jesus. Christians believe that Jesus was the incarnated Son of God, divine, and sinless. Islam teaches that Jesus was one of the most important prophets of God, but not the Son of God, not divine, and not part of the Trinity. Rather, Muslims believe the creation of Jesus was similar to the creation of Adam (Adem).
Christianity and Islam also differ in their fundamental views related to the crucifixion and resurrection of Jesus. Christianity teaches that Jesus was condemned to death by the Sanhedrin and the Roman prefect Pontius Pilate, crucified, and after three days, resurrected. Islam teaches that Jesus was a human prophet who, like the other prophets, tried to bring his people to worship God, termed Tawhid. Muslims also believe that Jesus was condemned to crucifixion and then miraculously saved from execution, and was raised to the heavens. In Islam, instead of Jesus being crucified, his lookalike was crucified.
Both Christians and Muslims believe in the Second Coming of Jesus. Christianity does not state where will Jesus return, while the Hadith in Islam states that Jesus will return at a white minaret at the east of Damascus (believed to be the Minaret of Isa in the Umayyad Mosque), and will pray behind Mahdi. Christians believe that Jesus will return to kill the Antichrist and similarly Muslims believe that Jesus will return to kill Dajjal. Many Christians believe that Jesus would then rule for 1,000 years, while Muslims believe Jesus will rule for forty years, marry, have children and will be buried at the Green Dome.
Muhammad
Muslims believe that Muhammad was a prophet, who received revelations (Quran) by God through the angel Gabriel (Jibril), gradually over a period of approximately 23 years, beginning on 22 December 609, when Muhammad was 40, and concluding in 632, the year of his death. Muslims regard the Quran as the most important miracle of Muhammad, a proof of his prophethood, and the culmination of a series of divine messages that started with the messages revealed to Adam and ended with Muhammad. Muslims also believe that the reference to the Paraclete in the Bible is a prophecy of the coming of Muhammad.
Muslims revere Muhammad as the embodiment of the perfect believer and take his actions and sayings as a model of ideal conduct. Unlike Jesus, who Christians believe was God's son, Muhammad was a mortal, albeit with extraordinary qualities. Today many Muslims believe that it is wrong to represent Muhammad, but this was not always the case. At various times and places pious Muslims represented Muhammad although they never worshiped these images.
During the lifetime of Muhammad, he had many interactions with Christians. One of the first Christians who met Muhammad was Waraqah ibn Nawfal, a Christian priest of ancient Arabia. He was one of the first hanifs to believe in the prophecy of Muhammad. Muhammad also met the Najrani Christians and made peace with them. One of the earliest recorded comment of a Christian reaction to Muhammad can be dated to only a few years after Muhammad's death. As stories of the Arab prophet spread to Christian Syria, an old man who was asked about the "prophet who has appeared with the Saracens" responded: "He is false, for the prophets do not come armed with a sword."
God
In Christianity, the most common name of God is Yahweh. In Islam, the most common name of God is Allah, similar to Eloah in the Old Testament. The vast majority of the world's Christians adhere to the doctrine of the Trinity, which in creedal formulations states that God is three hypostases (the Father, the Son and the Spirit) in one ousia (substance). In Islam, this concept is deemed to be a denial of monotheism, and thus a sin of shirk, which is considered to be a major 'al-Kaba'ir' sin. The Quran itself refers to Trinity in Al-Ma'ida 5:73 which says "They have certainly disbelieved who say, "Allah is the third of three." And there is no god except one God. And if they do not desist from what they are saying, there will surely afflict the disbelievers among them a painful punishment." Islam has the concept of Tawhid which is the concept of a single, indivisible God, who has no partners.
The Holy Spirit
Christians and Muslims have differing views about the Holy Spirit. Most Christians believe that the Holy Spirit is God, and the third member of the Trinity. In Islam, the Holy Spirit is generally believed to be the angel Gabriel. Most Christians believe that the Paraclete referred to in the Gospel of John, who was manifested on the day of Pentecost, is the Holy Spirit. Most Muslims believe that the reference to the Paraclete is a prophecy of the coming of Muhammad.
One of the key verses concerning the Paraclete is John 16:7:
Salvation
The Catechism of the Catholic Church, the official doctrine document released by the Roman Catholic Church, has this to say regarding Muslims:
Protestant theology mostly emphasizes the necessity of faith in Jesus as a savior in order for salvation. Muslims may receive salvation in theologies relating to Universal reconciliation, but will not according to most Protestant theologies based on justification through faith:
The Quran explicitly promises salvation for all those righteous Christians who were there before the arrival of Muhammad:
The Quran also makes it clear that the Christians will be nearest in love to those who follow the Quran and praises Christians for being humble and wise:
Early and Medieval Christian writers on Islam and Muhammad
John of Damascus
In 746 John of Damascus (sometimes St. John of Damascus) wrote the Fount of Knowledge part two of which is entitled Heresies in Epitome: How They Began and Whence They Drew Their Origin. In this work St. John makes extensive reference to the Quran and, in St. John's opinion, its failure to live up to even the most basic scrutiny. The work is not exclusively concerned with the Ismaelites (a name for the Muslims as they claimed to have descended from Ismael) but all heresy. The Fount of Knowledge references several suras directly often with apparent incredulity.
Theophanes the Confessor
Theophanes the Confessor (died c.822) wrote a series of chronicles (284 onwards and 602-813 AD) based initially on those of the better known George Syncellus. Theophanes reports about Muhammad thus:
Niketas
In the work A History of Christian-Muslim Relations Hugh Goddard mentions both John of Damascus and Theophanes and goes on to consider the relevance of Niketas Byzantios who formulated replies to letters on behalf of Emperor Michael III (842-867). Goddard sums up Niketas' view:
Goddard further argues that Niketas demonstrates in his work a knowledge of the entire Quran, including an extensive knowledge of Suras 2-18. Niketas' account from behind the Byzantine frontier apparently set a strong precedent for later writing both in tone and points of argument.
11th century
Knowledge and depictions of Islam continued to be varied within the Christian West during the 11th century. For instance, the author(s) of the 11th century Song of Roland evidently had little actual knowledge of Islam. As depicted in this epic poem, Muslims erect statues of Mohammed and worship them, and Mohammed is part of an "Unholy Trinity" together with the Classical Greek Apollyon and Termagant, a completely fictional deity. This view, evidently confusing Islam with the pre-Christian Graeco-Roman Religion, appears to reflect misconceptions prevalent in Western Christian society at the time.
On the other hand, ecclesiastic writers such as Amatus of Montecassino or Geoffrey Malaterra in Norman Southern Italy, who occasionally lived among Muslims themselves, would depict at times Muslims in a negative way but would depict equally any other (ethnic) group that was opposed to the Norman rule such as Byzantine Greeks or Italian Lombards. Often the depictions would depend on context: when writing about neutral events, Muslims would be called according to geographical terms such as "Saracens" or "Sicilians, when reporting events where Muslims came into conflict with Normans, Muslims would be called "pagans" or "infidels".
Similarities were occasionally acknowledged such as by Pope Gregory VII wrote in a letter to the Hammadid emir an-Nasir that both Christians and Muslims "worship and confess the same God though in diverse forms and daily praise".
The Divine Comedy
In Dante Alighieri's Divine Comedy, Muhammad is in the ninth ditch of Malebolge, the eighth realm, designed for those who have caused schism; specifically, he was placed among the Sowers of Religious Discord. Muhammad is portrayed as split in half, with his entrails hanging out, representing his status as a heresiarch (Canto 28).
This scene is frequently shown in illustrations of the Divine Comedy. Muhammad is represented in a 15th-century fresco Last Judgment by Giovanni da Modena and drawing on Dante, in the San Petronio Basilica in Bologna, as well as in artwork by Salvador Dalí, Auguste Rodin, William Blake, and Gustave Doré.
Catholic Church and Islam
Second Vatican Council and Nostra aetate
The question of Islam was not on the agenda when Nostra aetate was first drafted, or even at the opening of the Second Vatican Council. However, as in the case of the question of Judaism, several events came together again to prompt a consideration of Islam. By the time of the Second Session of the Council in 1963 reservations began to be raised by bishops of the Middle East about the inclusion of this question. The position was taken that either the question will not be raised at all, or if it were raised, some mention of the Muslims should be made. Melkite patriarch Maximos IV was among those pushing for this latter position.
Early in 1964 Cardinal Bea notified Cardinal Cicognani, President of the Council's Coordinating Commission, that the Council fathers wanted the Council to say something about the great monotheistic religions, and in particular about Islam. The subject, however, was deemed to be outside the competence of Bea's Secretariat for the Promotion of Christian Unity. Bea expressed willingness to "select some competent people and with them to draw up a draft" to be presented to the Coordinating Commission. At a meeting of the Coordinating Commission on 16–17 April Cicognani acknowledged that it would be necessary to speak of the Muslims.
The period between the first and second sessions saw the change of pontiff from Pope John XXIII to Pope Paul VI, who had been a member of the circle (the Badaliya) of the Islamologist Louis Massignon. Pope Paul VI chose to follow the path recommended by Maximos IV and he therefore established commissions to introduce what would become paragraphs on the Muslims in two different documents, one of them being Nostra aetate, paragraph three, the other being Lumen gentium, paragraph 16.
The text of the final draft bore traces of Massignon's influence. The reference to Mary, for example, resulted from the intervention of Monsignor Descuffi, the Latin archbishop of Smyrna with whom Massignon collaborated in reviving the cult of Mary at Smyrna. The commendation of Muslim prayer may reflect the influence of the Badaliya.
In Lumen gentium, the Second Vatican Council declares that the plan of salvation also includes Muslims, due to their professed monotheism.
Recent Catholic-Islamic controversies
For the controversy surrounding Muslim prayer in Spain, see Muslim campaign at Córdoba Cathedral
For criticism of interfaith dialogue with Muslims, see Pierre Claverie#Relations with Islam
For the controversy over whether Islam is a religion or a political system, see Raymond Leo Burke#Islam and immigration
For the controversy over advice not to marry a Muslim and move to an Islamic country, see José Policarpo#Marriages with Muslim men
For the controversy over whether Catholics may call God "Allah" if they want to, see Titular Roman Catholic Archbishop of Kuala Lumpur v Menteri Dalam Negeri
For the controversy over remarks by Pope Benedict XVI, see Regensburg lecture and Pope Benedict XVI and Islam
Protestantism and Islam
Protestantism and Islam entered into contact during the 16th century, at a time when Protestant movements in northern Europe coincided with the expansion of the Ottoman Empire in southern Europe. As both were in conflict with the Catholic Holy Roman Empire, numerous exchanges occurred, exploring religious similarities and the possibility of trade and military alliances. Relations became more conflictual in the early modern and modern periods, although recent attempts have been made at rapprochement.
Mormonism and Islam
Mormonism and Islam have been compared to one another ever since the earliest origins of the former in the nineteenth century, often by detractors of one religion or the other—or both. For instance, Joseph Smith, the founding prophet of Mormonism, was referred to as "the modern Mahomet" by the New York Herald, shortly after his murder in June 1844. This epithet repeated a comparison that had been made from Smith's earliest career, one that was not intended at the time to be complimentary. Comparison of the Mormon and Muslim prophets still occurs today, sometimes for derogatory or polemical reasons but also for more scholarly and neutral purposes. While Mormonism and Islam certainly have many similarities, there are also significant, fundamental differences between the two religions. Mormon–Muslim relations have historically been cordial; recent years have seen increasing dialogue between adherents of the two faiths, and cooperation in charitable endeavors, especially in the Middle and Far East.
Christianity and Druze
Christianity and Druze are Abrahamic religions that share a historical traditional connection with some major theological differences. The two faiths share a common place of origin in the Middle East, and consider themselves to be monotheistic. Even though the faith originally developed out of Ismaili Islam, Druze do not identify as Muslim.
The relationship between the Druze and Christians has been characterized by harmony and coexistence, with amicable relations between the two groups prevailing throughout history, with the exception of some periods, including 1860 Mount Lebanon civil war. Over the centuries a number of the Druze embraced Christianity, such as some of Shihab dynasty members, as well as the Abi-Lamma clan.
Contact between Christians (members of the Maronite, Eastern Orthodox, Melkite and other churches) and the Unitarian Druze led to the presence of mixed villages and towns in Mount Lebanon, Jabal al-Druze, Galilee, and Mount Carmel. The Maronites and the Druze founded modern Lebanon in the early eighteenth century, through the ruling and social system known as the "Maronite-Druze dualism" in Mount Lebanon Mutasarrifate.
Christianity does not include belief in reincarnation or the transmigration of the soul, unlike the Druze. Christians engage in evangelism, often through the establishment of missions, unlike the Druze who do not accept converts; even marriage outside the Druze faith is rare and strongly discouraged. Similarities between the Druze and Christians include commonalities in their view of views on marriage and divorce, as well as belief in the oneness of God and theophany. The Druze faith incorporates some elements of Christianity, and other religious beliefs.
Both faiths give a prominent place to Jesus: Jesus is the central figure of Christianity, and in the Druze faith, Jesus is considered an important prophet of God, being among the seven prophets who appeared in different periods of history. Both religions venerated John the Baptist, Saint George, Elijah, and other common figures.
Artistic influences
Islamic art and culture have both influenced and been influenced by Christian art and culture. Some arts have received such influence strongly, particularly religious architecture in the Byzantine and medieval eras
See also
Ashtiname of Muhammad
Chrislam (Yoruba), a syncretist religion
Christian influences in Islam
Christian philosophy
Christianity and other religions
Christianity and war
Crusades
Constantinople
Divisions of the world in Islam
Islam and other religions
Islamic philosophy
Islam and war
Muhammad's views on Christians
References
Further reading
Abdiyah Akbar Abdul-Haqq, Sharing Your [Christian] Faith with a Muslim, Minneapolis: Bethany House Publishers, 1980.
Giulio Basetti-Sani, The Koran in the Light of Christ: a Christian Interpretation of the Sacred Book of Islam, trans. by W. Russell-Carroll and Bede Dauphinee, Chicago, Ill.: Franciscan Herald Press, 1977.
Roger Arnaldez, Jésus: Fils de Marie, prophète de l'Islam, coll. Jésus et Jésus-Christ, no 13, Paris: Desclée, 1980.
Kenneth Cragg, The Call of the Minaret, Third ed., Oxford: Oneworld [sic] Publications, 2000, xv, 358 p.
Maria Jaoudi, Christian & Islamic Spirituality: Sharing a Journey, Mahwah, N.J.: Paulist Press, 1992. iii, 103 p.
Jane Dammen McAuliffe, Qur'anic Christians: An Analysis of Classical and Modern Exegesis, Cambridge: Cambridge University Press, 1991.
Frithjof Schuon, Christianity/Islam: Essays on Esoteric Ecumenicism, in series, The Library of Traditional Wisdom, Bloomington, Ind.: World Wisdom Books, cop. 1985. vii, 270 p. N.B.: Trans. from French. ; the ISBN on the verso of the t.p. surely is erroneous.
Mark D. Siljander and John David Mann, A Deadly Misunderstanding: a Congressman's Quest to Bridge the Muslim-Christian Divide, New York: Harper One, 2008. .
Robert Spencer, Not Peace But a Sword: The Great Chasm Between Christianity and Islam. Catholic Answers. March 25, 2013. .
Thomas, David, Muhammad in Medieval Christian-Muslim Relations (Medieval Islam), in Muhammad in History, Thought, and Culture: An Encyclopedia of the Prophet of God (2 vols.), Edited by C. Fitzpatrick and A. Walker, Santa Barbara, ABC-CLIO, 2014, Vol. I, pp. 392–400. 1610691776
External links
Hasib Sabbagh: A Legacy of Understanding from the Dean Peter Krogh Foreign Affairs Digital Archives
"I'm Right, You're Wrong, Go to Hell" – Religions and the meeting of civilization by Bernard Lewis
Islam & Christianity (IRAN & GEORGIA) News Photos | wiki |
Fräsa kan avse:
Fräsa – upphetta ett livsmedel på svag värme i matfett utan att det får färg, se stekning
Fräsning – att bearbeta ett material med en fräsmaskin | wiki |
The term Abgal refers to the Seven Sages of Ancient Mesopotamian tradition.
Abgal may also refer to:
Abgal (god), a Palmyrene deity
See also
Abgaal, a Somali clan
Abigail (disambiguation) | wiki |
Koogle is a flavored peanut butter brand.
Koogle may also refer to:
Jacob Koogle, Medal of Honor recipient during the American Civil War
Timothy Koogle, first CEO of Yahoo! | wiki |
EM TV can refer to:
EM TV, a commercial television station in Papua New Guinea
Controversial TV, a former commercial television station in the United Kingdom previously known as Edge Media Television
Constantin Medien AG (formerly EM.TV & Merchandising AG), a German media group. | wiki |
Le mont Kubrick (Kubrick Mons) est une montagne située sur Charon, nommée d'après le réalisateur Stanley Kubrick. La montagne est située dans une dépression, elle-même située dans la plaine Vulcain. La façon dont elle s'est formée est inconnue.
Notes et références
Géographie de Charon
Mons | wiki |
Eric Phillips may refer to:
Eric Phillips (athlete) (born 1954), Venezuelan Olympic sprinter
Eric G. Phillips, founder and CEO of Phillips enterprise
Eric Phillips, a character on the soap opera Home and Away | wiki |
Politics of China is the politics of the People's Republic of China, a single-party socialist republic.
Politics of China may also refer to
Politics of the Republic of China, commonly known as Taiwan
Politics of the special administrative regions of the People's Republic of China
Politics of Hong Kong
Politics of Macau
Political systems of Imperial China from 221 BC to 1912 AD
See also
Cross-Strait relations
History of political parties in China | wiki |
Big Four Ski Area was an alpine ski area that operated in Washington state on the north side of Big Four Mountain approximately 26 miles east of Granite Falls, Washington. Was opened during the early 19th century, and was part of the Big Four Mountain Inn, first serviced by railroad. Located in the Stillaguamish River Valley, below the ice cave basin. Closed before 1949, when the Inn was destroyed by fire. Little else is known about the ski area.
References
Defunct ski areas and resorts in Washington (state)
Ski areas and resorts in Washington (state)
Cascade Range
Buildings and structures in Snohomish County, Washington | wiki |
1857 earthquake may refer to:
1857 Basilicata earthquake (Italy)
1857 Fort Tejon earthquake (California, US)
1857 Parkfield earthquake, see collective article Parkfield earthquake (California, US)
See also
List of historical earthquakes | wiki |
Gerald Miller may refer to:
Gerald Miller (missionary) (born 1937), Mennonite medical missionary
Gerald L. Miller (born 1942), United States Marine Corps general
Gerald A. Miller (born 1943), American agronomist and professor
Gerald E. Miller (1919–2014), United States Navy admiral
Gerald R. Miller (1931–1993), American professor and author
See also
Gerry Miller (disambiguation)
Jerry Miller (disambiguation) | wiki |
Hazel Crest – wieś w Stanach Zjednoczonych, w stanie Illinois, w hrabstwie Cook.
Wsie w stanie Illinois | wiki |
1812 earthquake may refer to:
1812 Caracas earthquake (Venezuela)
1811–12 New Madrid earthquakes (Mississippi River, US) (river tsunamis)
1812 San Juan Capistrano earthquake (California, US), also known as the Wrightwood earthquake
1812 Ventura earthquake (California, US), also known as the Mission San Buenaventura or Santa Barbara earthquake
See also
List of historical earthquakes | wiki |
Irene Marie Models was a modeling and talent agency in Miami Beach, Florida. The agency was one of South Florida's first exclusive agencies. The agency closed in 2009.
History
Irene Marie Models was founded in 1983 in Fort Lauderdale, Florida by former international fashion model and fashion columnist Irene Marie. In 1989 Irene moved to South Beach.
In 2006 Irene Marie along with MTV launched 8th & Ocean, a television series chronicling the lives of models and staff at the Irene Marie Modeling agency.
Models and actors represented by Irene Marie
Amber Smith
Bar Refaeli
Brett Novek
Cindy Taylor
Cynthia Bailey
David Fumero
Galen Gering
Garcelle Beauvais
Melania Trump
Niki Taylor
Eugena Washington
See also
List of modeling agencies
References
Modeling agencies
1983 establishments in the United States
Entertainment companies established in 1983
Companies disestablished in 2009
Miami Beach, Florida | wiki |
Men and boys are more frequently diagnosed with autism than women and girls. It is debated whether this is due to a sex difference in rates of autism spectrum disorders (ASD) or whether females are underdiagnosed. The prevalence ratio is often cited as about 4 males for every 1 female diagnosed. Other research indicates that it closer to 3:1 or 2:1. One in every 42 males and one in 189 females in the United States is diagnosed with autism spectrum disorder. There is some evidence that females may also receive diagnoses somewhat later than males; however, thus far results have been contradictory.
Several theories exist to explain the sex-based discrepancy, such as a genetic protective effect, the extreme male brain theory and phenotypic differences in the presentation between sexes, which may all be intertwined. Researchers have also debated whether a diagnostic gender bias has played a role in females being underdiagnosed with autism spectrum disorder. Researchers have also speculated a gender bias in parental reporting due to the expectations and socialization of gender roles in society.
Since autism is a largely genetic and hereditary condition, genetic factors that lead to differences depending on sex come into play, such as the role of androgen signaling in male development or X-linked mutations, whose associated genetic conditions are typically more common and severe in males. The extreme male brain theory suggests that autistic brains show an exaggeration of the features associated with male brains, such as increased size and decreased relative connectivity as well as systematic thinking over empathetic thinking. The imprinted brain hypothesis suggests genomic imprinting is at least partly responsible for the sex differences in autism and points to the evidence for a common genetic cause with schizophrenia.
Compared to men, women are generally required to be more impaired by their autism or have more cognitive or behavioral conditions than their male counterparts to meet autism spectrum criteria. There is evidence of increased incidence of social anxiety, anorexia nervosa and self-harm in autistic females, though the increased rates of anorexia nervosa and other eating disorders may be due to confusion or conflation with avoidant/restrictive food intake disorder (ARFID), which is particularly common in autism.
Autistic girls and women show higher social motivation and a greater capacity for typical friendships than autistic boys and men, are less likely to be hyperactive, impulsive, have issues with conduct or stereotyped behavioral traits, and have been shown to mask their conditions more frequently than autistic men. Autistic males often exhibit more easily observed behaviors at a younger age resulting in parental observance and subsequent evaluation of the child. In contrast, behavior of young females is more often overlooked, regardless of any associated at-risk factors for ASD or other developmental delays. Ultimately, this may contribute to females more frequently receiving their ASD diagnosis later in life than their male counterpart. There is a growing consensus among neuroscientists that the number of autistic women has been vastly underrepresented due to the assumption that it is primarily a male condition.
Background
Hans Asperger was one of the first people to study autism, with all of his four study subjects being male. Another early researcher, Leo Kanner described "autistic disturbances of affective contact" in the group consisting of eight boys and three girls.
Today, Autism Spectrum Disorder is commonly defined as a neurological developmental disorder with symptoms of poor social communication, repetitive behaviors, sensory sensitivities, executive dysfunction, and hyper-fixations. In the modern day, women are less likely to be diagnosed as autistic than men; they are often misdiagnosed or not noticed to be neurodivergent by doctors. Women are also more likely to be diagnosed as autistic at a later age than men. This discrepancy in diagnoses is believed to be caused by Camouflaging, a common autistic phenotype presented in females, which hides autistic traits.
Theories explaining gender diagnosis disparity
Extreme male brain theory
Extreme Male Brain Theory is an extension of the Empathizing-Systemizing Theory, which categorizes people into 5 different groups based on their empathizing and systemizing expressions. In the general neurotypical population, females have a greater ability to empathize, and males have a greater ability to systemize. Simon Baron-Cohen's extreme male brain theory states that autistic males have higher doses of prenatal testosterone and on average have a more systemizing brain, as opposed to the more empathizing female brain. He suggests that autistic brains show an exaggeration of the features associated with male brains. These are mainly size and connectivity, with males generally having a larger brain, which is seen in an exaggerated form in those with ASD. Individuals with ASD were found to have widespread abnormalities in interconnectivity and general functioning in specific brain regions. This could explain the different results on empathy tests between men and women as well as the deficiencies in empathy seen in ASD, as empathy requires several brain regions to be activated which need information from many different areas of the brain. Baron-Cohen therefore argues that genetic factors play a role in autism prevalence and that children with technically minded parents are more likely to be diagnosed with autism. Although autistic females have been documented to have higher testosterone levels, which could support the Extreme Male Brain theory, not all autistic females show male-specific symptoms, leaving the Extreme Male Brain theory with Autism Spectrum Disorder to be controversial.
Imprinted brain hypothesis
The imprinted brain theory suggests genomic imprinting is at least partly responsible for the sex differences in autism and implicates schizophrenia as well, claiming that genetic and physiological evidence suggests the two conditions are on a spectrum in which some mutations in certain genes cause lower social cognition but higher practical cognition (autism) while other mutations in the same genes cause lower practical cognition with higher social cognition (schizophrenia).
Female protective effect hypothesis
According to the female protective effect hypothesis, more extreme genetic mutations are required for a girl to develop autism than for a boy. In 2012, Harvard researchers published findings suggesting that, on average, more genetic and environmental risk factors are required for girls to develop autism, compared to boys. The researchers analyzed DNA samples of nearly 800 families affected by autism and nearly 16,000 individuals with a variety of neurodevelopmental disorders. They looked for various types of gene mutations. Overall, they found that females diagnosed with autism or another neurodevelopmental disorder had a greater number of harmful mutations throughout the genome than did males with the same disorders. Women with an extra X chromosome, 47,XXX or triple X syndrome, have autism-like social impairments in 32% of cases.
Hypothesis of female under-diagnosis
The prevalence ratio is often cited as about 4 males for every 1 female diagnosed. Other research indicates that it closer to 3:1 or 2:1.
Some authors, clinicians and experts like Judith Gould, Tony Attwood, Lorna Wing and Christopher Gillberg have proposed that autism in females may be underdiagnosed due to better natural superficial social mimicry skills in females, partially different set of symptoms and less knowledge about autism in females among experts. In his preword to the book Asperger's and Girls, Attwood writes: "These tentative explanations for the apparent underrepresentation of girls with Asperger's Syndrome have yet to be examined by objective research studies."
Specifically, Gould has discussed the idea that a pervasive developmental disorder called pathological demand avoidance, which is not officially included in diagnostic manuals, may offer a glimpse into how autism in females may present in some cases.
Another clinician, William Mandy, hypothesized referrals for ASD assessment are often started by teachers. Girls with ASD may sometimes lack the skills of social communication and this is not noticed until they are in a school setting. Therefore, girls suggested to have ASD may receive delayed or no clinical assessment. Compared with males, females with autism are more likely to mask their restricted interests (strong or intense interests in specific topics or objects), which could decrease the chances of diagnosis.
Female phenotype
Some have suggested a differential phenotype for autistic women; "a female-specific manifestation of autistic strengths and difficulties, which fits imperfectly with current, male-based conceptualisations" of autism. Autistic women have been shown to score higher in self-reports of , which may factor into the different phenotype. One study found evidence for a diagnostic bias against girls who meet criteria for ASD. In some cases where females showed severe autistic traits, they failed to meet the criteria for a diagnosis, because of the lack of sensitivity to the female phenotype.
Camouflaging
The DSM-5 mainly looks at two categories of autism spectrum symptoms when diagnosing someone: social deficits and restricted/repetitive behaviors and interests. Both of these categories of symptoms can be hidden by an aspect of the autistic female phenotype known as Camouflaging.
Autistic girls tend to camouflage more than boys, this leads to many of their symptoms being hidden and not noticed by professionals. When it comes to social camouflaging, there are three sub-categories according to the Camouflaging Autistic Traits Questionnaire (CAT-Q): Masking, Assimilation, and Compensation. Masking is the act of constantly monitoring one's behavior in order to hide one's autistic traits and/or putting on a fake persona. Assimilation is known as "hiding in plain sight" or trying to blend in with non-autistic peers. Finally, compensation is trying to over-compensate for a lack of social abilities. Examples of this can include mimicking real or fictional people, over exaggerating non-verbal expressions, and creating scripts or rules when having a conversion with someone.
Camouflaging can also be used to hide repetitive/restricted behaviors and interests. In fact, researchers have found that autistic girls are ten times more likely to not originally meet the DSM-5 criteria for restricted/repetitive behaviors. Sensory overstimulation is another autistic trait that can be hidden by masking. Participants of the Hull, et al, would internalize their overwhelming feelings and try to channel it through small and unnoticeable everyday objects. If those objects were not enough to calm them down, then they would try to leave the environment and recuperate by making “ regular excuses'' as to why they needed to leave.
Downfalls of camouflaging
Studies have shown that high levels of camouflaging is can lead to higher levels of anxiety and depression and can increase the risk of suicidal ideation. Studies have also found that camouflaging can lead to a skewed sense of self. This is especially the case for people who had been masking and mimicking other people for long periods of time. Another factor of masking is mental and physical exhaustion after a camouflaging session. According to the participants of the Hull, et al (2017) study, the longer that autistic individuals camouflage, the worse the exhaustion becomes and the longer these individuals need to rest and recharge. This study had also found that there were increased amounts of anxiety and stress revolving around camouflaging because the participants were often worried that they did not mask enough, did not mask correctly, or did not reach the desired effects of masking in that camouflaging session. Another one of the factors that increased anxiety and exhaustion while camouflaging is the fact that it “involved a constant monitoring of the situation, as if training oneself in self-monitoring, self-awareness, and monitoring others’ reactions, both during and after the interaction occurred."
Differences in gender and sexuality identification
Sexuality is often discussed within the autistic community, with many observations that identities other than cis-hetero seem to be more common than is observed in the neurotypical population. There have not been many formal studies on this to date, however members of the community speculate that autistic individuals generally have different ideals, perceptions and desires than neurotypicals or simply do not comprehend or agree with society's expectation, making them more apt to diverge from the norm.
A study looking at the co-occurrence of ASD in patients with gender dysphoria found 7.8% of patients to be on the autism spectrum. Another study consisting of online surveys that included those who identified as nonbinary and those identifying as transgender without diagnoses of gender dysphoria found the number to be as high as 24% of gender diverse people having autism, versus around 5% of the surveyed cisgender people. A possible hypothesis for the correlation may be that autistic people are less able to conform to societal norms, which may explain the high number of autistic individuals who identify outside the stereotypical gender binary. As of yet, there have been no studies specifically addressing the occurrence of autism in intersex individuals.
A study conducted by Byers and Nichols (2014) explored the level of sexual satisfaction of high-functioning autistic individuals, with researchers testing the sexual and relationship satisfaction of neurotypical versus high functioning autistic individuals. The results suggest that men with ASD are generally less satisfied with their relationship or marriage compared to neurotypical men and women, and women with ASD.
See also
Epidemiology of autism
Gender bias in psychological diagnosis
Mental disorders and gender
Sex differences in schizophrenia
Autism Diagnostic Interview
References
Autism
Autism | wiki |
School of Public Health may refer to one or more of the following educational institutions offering instruction in public health or related fields:
Africa
Makerere University School of Public Health, Makerere University College of Health Sciences, Kampala, Uganda
University of Zambia School of Public Health, Lusaka, Zambia
Asia
Hanoi School of Public Health, Hanoi, Vietnam
Europe
Andalusian School of Public Health, Granada, Spain
National School of Public Health (Spain), Carlos III Health Institute, Madrid, Spain
North America
Canada
Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario
United States
Boston University School of Public Health, Boston University, Boston, MA
Brown University School of Public Health, Brown University, Providence, RI
Columbia University Mailman School of Public Health, Columbia University, New York City, NY
Colorado School of Public Health, Colorado
CUNY Graduate School of Public Health & Health Policy, City University of New York, New York City, NY
Drexel University School of Public Health, Drexel University, Philadelphia, PA
Graduate School of Public Health, San Diego State University, San Diego, CA
Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA
Herbert Wertheim School of Public Health and Human Longevity Science, University of California, San Diego, San Diego, CA
Indiana University School of Public Health-Bloomington, Indiana University Bloomington, Bloomington, IN
Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD
Joseph J. Zilber School of Public Health, University of Wisconsin–Milwaukee, Milwaukee, WI
Milken Institute School of Public Health, George Washington University, Washington D.C.
Rollins School of Public Health, Emory University, Atlanta, GA
Rutgers School of Public Health, Rutgers University, New Jersey
Texas A&M School of Public Health, Texas
Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA
UCLA Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA
University of California, Berkeley School of Public Health, University of California, Berkeley, Berkeley, CA
University of Maryland School of Public Health, University of Maryland, College Park, College Park, MD
University of Michigan School of Public Health, University of Michigan, Ann Arbor, MI
University of Minnesota School of Public Health, University of Minnesota, Minneapolis, MN
University of Pittsburgh Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA
University of Washington School of Public Health, University of Washington, Seattle, WA
UNC Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC
UTHealth School of Public Health, University of Texas Health Science Center at Houston, Houston, TX
West Virginia University School of Public Health, West Virginia University, Morgantown, WV
Yale School of Public Health, Yale University, New Haven, CT | wiki |
UDPG may refer to:
Uridine diphosphate glucose
Uridine diphosphate glucuronic acid | wiki |
A Stirling engine is a heat engine that is operated by the cyclic compression and expansion of air or other gas (the working fluid) between different temperatures, resulting in a net conversion of heat energy to mechanical work.
More specifically, the Stirling engine is a closed-cycle regenerative heat engine with a permanent gaseous working fluid. Closed-cycle, in this context, means a thermodynamic system in which the working fluid is permanently contained within the system, and regenerative describes the use of a specific type of internal heat exchanger and thermal store, known as the regenerator. Strictly speaking, the inclusion of the regenerator is what differentiates a Stirling engine from other closed-cycle hot air engines.
In the Stirling engine, a gas is heated and expanded by energy supplied from outside the engine's interior space (cylinder). It is then shunted to a different location within the engine, where it is cooled and compressed. A piston (or pistons) move the gas to the correct places within the engine, at the correct time in the cycle, and extracts mechanical power from it. The gas oscillates between these heating and cooling spaces, changing temperature and pressure as it goes. A unique feature is the Regenerator, which acts as a temporary heat store by retaining heat within the machine rather than dumping it into the heat sink, thereby increasing its efficiency.
The heat is supplied from the outside, so the hot area of the engine can be warmed with any external heat source. Similarly, the cooler part of the engine can be maintained by an external heat sink, such as running water or air flow. The gas is permanently retained in the engine, allowing a gas with the most-suitable properties to be used, such as helium or hydrogen. There are no intake and no exhaust gas flows so the machine is practically silent.
The machine is reversible so that if the shaft is turned by an external power source a temperature difference will develop across the machine; in this way it acts as a heat pump.
The Stirling engine was invented by Scotsman Robert Stirling in 1816 as an industrial prime mover to rival the steam engine, and its practical use was largely confined to low-power domestic applications for over a century.
Contemporary investment in renewable energy, especially solar energy, has given rise to its application within concentrated solar power and as a heat pump.
History
Early hot air engines
Robert Stirling is considered one of the fathers of hot air engines, notwithstanding some earlier predecessors—notably Guillaume Amontons, who succeeded in building, in 1699, the first working hot air engine.
Amontons was later followed by Sir George Cayley. This engine type was of those in which the fire is enclosed, and fed by air pumped in beneath the grate in sufficient quantity to maintain combustion, while by far the largest portion of the air enters above the fire, to be heated and expanded; the whole, together with the products of combustion, then acts on the piston, and passes through the working cylinder; and the operation being one of simple mixture only, no heating surface of metal is required, the air to be heated being brought into immediate contact with the fire.
Stirling came up with a first air engine in 1816. The principle of the Stirling Air Engine differs from that of Sir George Cayley (1807), in which the air is forced through the furnace and exhausted, whereas in Stirling's engine the air works in a closed circuit. The inventor devoted most of his attention to that.
A engine, built in 1818 for pumping water at an Ayrshire quarry, continued to work for some time, until a careless attendant allowed the heater to become overheated. This experiment proved to the inventor that, owing to the low working pressure obtainable, the engine could only be adapted to small powers for which there was, at that time, no demand.
The Stirling 1816 patent was also about an "Economiser", which is the predecessor of the regenerator. In this patent (# 4081) he describes the "economiser" technology and several applications where such technology can be used. Out of them came a new arrangement for a hot air engine.
Stirling patented a second hot air engine, together with his brother James, in 1827. They inverted the design so that the hot ends of the displacers were underneath the machinery, and they added a compressed air pump so the air within could be increased in pressure to around .
The two Stirling brothers were followed shortly after (1828) by Parkinson & Crossley and Arnott in 1829.
These precursors, to whom Ericsson should be added, have brought to the world the hot air engine technology and its enormous advantages over the steam engine. Each of them came with his own specific technology, and although the Stirling engine and the Parkinson & Crossley engines were quite similar, Robert Stirling distinguished himself by inventing the regenerator.
Parkinson and Crosley introduced the principle of using air of greater density than that of the atmosphere, and so obtained an engine of greater power in the same compass. James Stirling followed this same idea when he built the famous Dundee engine.
The Stirling patent of 1827 was the base of the Stirling third patent of 1840. The changes from the 1827 patent were minor but essential, and this third patent led to the Dundee engine.
James Stirling presented his engine to the Institution of Civil Engineers in 1845. The first engine of this kind which, after various modifications, was efficiently constructed and heated, had a cylinder of in diameter, with a length of stroke of , and made 40 strokes or revolutions in a minute (40 rpm). This engine moved all the machinery at the Dundee Foundry Company's works for eight or ten months, and was previously found capable of raising 320,000 kg (700,000 lbs) 60 cm (2 ft) in a minute, a power of approximately .
Finding this power insufficient for their works, the Dundee Foundry Company erected the second engine, with a cylinder of in diameter, a stroke of , and making 28 strokes in a minute. When this engine had been in continual operation for upwards of two years, it had not only performed the work of the foundry in the most satisfactory manner, but had been tested (by a friction brake on a third mover) to the extent of lifting nearly , a power of approximately .
Invention and early development
The Stirling engine (or Stirling's air engine as it was known at the time) was invented and patented in 1816. It followed earlier attempts at making an air engine but was probably the first put to practical use when, in 1818, an engine built by Stirling was employed pumping water in a quarry. The main subject of Stirling's original patent was a heat exchanger, which he called an "economiser" for its enhancement of fuel economy in a variety of applications. The patent also described in detail the employment of one form of the economiser in his unique closed-cycle air engine design in which application it is now generally known as a "regenerator". Subsequent development by Robert Stirling and his brother James, an engineer, resulted in patents for various improved configurations of the original engine including pressurization, which by 1843, had sufficiently increased power output to drive all the machinery at a Dundee iron foundry.
A paper presented by James Stirling in June 1845 to the Institution of Civil Engineers stated that his aims were not only to save fuel but also to create a safer alternative to the steam engines of the time, whose boilers frequently exploded, causing many injuries and fatalities. This has, however, been disputed.
The need for Stirling engines to run at very high temperatures to maximize power and efficiency exposed limitations in the materials of the day, and the few engines that were built in those early years suffered unacceptably frequent failures (albeit with far less disastrous consequences than boiler explosions). For example, the Dundee foundry engine was replaced by a steam engine after three hot cylinder failures in four years.
Later 19th century
Subsequent to the replacement of the Dundee foundry engine there is no record of the Stirling brothers having any further involvement with air engine development, and the Stirling engine never again competed with steam as an industrial scale power source. (Steam boilers were becoming safer, e.g. the Hartford Steam Boiler and steam engines more efficient, thus presenting less of a target for rival prime movers). However, beginning about 1860, smaller engines of the Stirling/hot air type were produced in substantial numbers for applications in which reliable sources of low to medium power were required, such as pumping air for church organs or raising water. These smaller engines generally operated at lower temperatures so as not to tax available materials, and so were relatively inefficient. Their selling point was that unlike steam engines, they could be operated safely by anybody capable of managing a fire. The 1906 Rider-Ericsson Engine Co. catalog claimed that "any gardener or ordinary domestic can operate these engines and no licensed or experienced engineer is required". Several types remained in production beyond the end of the century, but apart from a few minor mechanical improvements the design of the Stirling engine in general stagnated during this period.
20th-century revival
During the early part of the 20th century, the role of the Stirling engine as a "domestic motor" was gradually taken over by electric motors and small internal combustion engines. By the late 1930s, it was largely forgotten, only produced for toys and a few small ventilating fans.
Around that time, Philips was seeking to expand sales of its radios into parts of the world where grid electricity and batteries were not consistently available. Philips' management decided that offering a low-power portable generator would facilitate such sales and asked a group of engineers at the company's research lab in Eindhoven to evaluate alternative ways of achieving this aim. After a systematic comparison of various prime movers, the team decided to go forward with the Stirling engine, citing its quiet operation (both audibly and in terms of radio interference) and ability to run on a variety of heat sources (common lamp oil – "cheap and available everywhere" – was favored). They were also aware that, unlike steam and internal combustion engines, virtually no serious development work had been carried out on the Stirling engine for many years and asserted that modern materials and know-how should enable great improvements.
By 1951, the 180/200 W generator set designated MP1002CA (known as the "Bungalow set") was ready for production and an initial batch of 250 was planned, but soon it became clear that they could not be made at a competitive price. Additionally, the advent of transistor radios and their much lower power requirements meant that the original reason for the set was disappearing. Approximately 150 of these sets were eventually produced. Some found their way into university and college engineering departments around the world, giving generations of students a valuable introduction to the Stirling engine; a letter dated March 1961 from Research and Control Instruments Ltd. London WC1 to North Devon Technical College, offering "remaining stocks... to institutions such as yourselves... at a special price of £75 net".
In parallel with the Bungalow set, Philips developed experimental Stirling engines for a wide variety of applications and continued to work in the field until the late 1970s, but only achieved commercial success with the "reversed Stirling engine" cryocooler. However, they filed a large number of patents and amassed a wealth of information, which they licensed to other companies and which formed the basis of much of the development work in the modern era.
In 1996, the Swedish navy commissioned three Gotland-class submarines. On the surface, these boats are propelled by marine diesel engines. However, when submerged, they use a Stirling-driven generator developed by Swedish shipbuilder Kockums to recharge batteries and provide electrical power for propulsion. A supply of liquid oxygen is carried to support burning of diesel fuel to power the engine. Stirling engines are also fitted to Swedish Södermanland-class submarines, the Archer-class submarines in service in Singapore, and the Japanese Sōryū-class submarines, with the engines license-built by Kawasaki Heavy Industries. In a submarine application, the Stirling engine offers the advantage of being exceptionally quiet when running.
21st-century developments
By the turn of the 21st century, Stirling engines were used in the dish version of Concentrated Solar Power systems. A mirrored dish similar to a very large satellite dish directs and concentrates sunlight onto a thermal receiver, which absorbs and collects the heat and using a fluid transfers it into the Stirling engine. The resulting mechanical power is then used to run a generator or alternator to produce electricity.
The core component of micro combined heat and power (CHP) units can be formed by a Stirling cycle engine, as they are more efficient and safer than a comparable steam engine. By 2003, CHP units were being commercially installed in domestic applications.
In 2013, an article was published about scaling laws of free-piston Stirling engines based on six characteristic dimensionless groups.
Name and classification
Robert Stirling patented the first practical example of a closed-cycle hot air engine in 1816, and it was suggested by Fleeming Jenkin as early as 1884 that all such engines should therefore generically be called Stirling engines. This naming proposal found little favour, and the various types on the market continued to be known by the name of their individual designers or manufacturers, e.g., Rider's, Robinson's, or Heinrici's (hot) air engine. In the 1940s, the Philips company was seeking a suitable name for its own version of the 'air engine', which by that time had been tested with working fluids other than air, and decided upon 'Stirling engine' in April 1945. However, nearly thirty years later, Graham Walker still had cause to bemoan the fact such terms as hot air engine remained interchangeable with Stirling engine, which itself was applied widely and indiscriminately, a situation that continues.
Like the steam engine, the Stirling engine is traditionally classified as an external combustion engine, as all heat transfers to and from the working fluid take place through a solid boundary (heat exchanger) thus isolating the combustion process and any contaminants it may produce from the working parts of the engine. This contrasts with an internal combustion engine, where heat input is by combustion of a fuel within the body of the working fluid. Most of the many possible implementations of the Stirling engine fall into the category of reciprocating piston engine.
Theory
The idealised Stirling cycle consists of four thermodynamic processes acting on the working fluid:
Isothermal expansion. The expansion-space and associated heat exchanger are maintained at a constant high temperature, and the gas undergoes near-isothermal expansion absorbing heat from the hot source.
Constant-volume (known as isovolumetric or isochoric) heat-removal. The gas is passed through the regenerator, where it cools, transferring heat to the regenerator for use in the next cycle.
Isothermal compression. The compression space and associated heat exchanger are maintained at a constant low temperature so the gas undergoes near-isothermal compression rejecting heat to the cold sink
Constant-volume (known as isovolumetric or isochoric) heat-addition. The gas passes back through the regenerator where it recovers much of the heat transferred in process 2, heating up on its way to the expansion space.
The engine is designed so the working gas is generally compressed in the colder portion of the engine and expanded in the hotter portion resulting in a net conversion of heat into work. An internal regenerative heat exchanger increases the Stirling engine's thermal efficiency compared to simpler hot air engines lacking this feature.
The Stirling engine uses the temperature difference between its hot end and cold end to establish a cycle of a fixed mass of gas, heated and expanded, and cooled and compressed, thus converting thermal energy into mechanical energy. The greater the temperature difference between the hot and cold sources, the greater the thermal efficiency. The maximum theoretical efficiency is equivalent to that of the Carnot cycle, but the efficiency of real engines is less than this value because of friction and other losses.
Since the Stirling engine is a closed cycle, it contains a fixed mass of gas called the "working fluid", most commonly air, hydrogen or helium. In normal operation, the engine is sealed and no gas enters or leaves; no valves are required, unlike other types of piston engines. The Stirling engine, like most heat engines, cycles through four main processes: cooling, compression, heating, and expansion. This is accomplished by moving the gas back and forth between hot and cold heat exchangers, often with a regenerator between the heater and cooler. The hot heat exchanger is in thermal contact with an external heat source, such as a fuel burner, and the cold heat exchanger is in thermal contact with an external heat sink, such as air fins. A change in gas temperature causes a corresponding change in gas pressure, while the motion of the piston makes the gas alternately expand and compress.
The gas follows the behaviour described by the gas laws that describe how a gas's pressure, temperature, and volume are related. When the gas is heated, the pressure rises (because it is in a sealed chamber) and this pressure then acts on the power piston to produce a power stroke. When the gas is cooled the pressure drops and this drop means that the piston needs to do less work to compress the gas on the return stroke. The difference in work between the strokes yields a net positive power output.
When one side of the piston is open to the atmosphere, the operation is slightly different. As the sealed volume of working gas comes in contact with the hot side, it expands, doing work on both the piston and on the atmosphere. When the working gas contacts the cold side, its pressure drops below atmospheric pressure and the atmosphere pushes on the piston and does work on the gas.
Components
As a consequence of closed-cycle operation, the heat driving a Stirling engine must be transmitted from a heat source to the working fluid by heat exchangers and finally to a heat sink. A Stirling engine system has at least one heat source, one heat sink and up to five heat exchangers. Some types may combine or dispense with some of these.
Heat source
The heat source may be provided by the combustion of a fuel and, since the combustion products do not mix with the working fluid and hence do not come into contact with the internal parts of the engine, a Stirling engine can run on fuels that would damage other engines types' internals, such as landfill gas, which may contain siloxane that could deposit abrasive silicon dioxide in conventional engines.
Other suitable heat sources include concentrated solar energy, geothermal energy, nuclear energy, waste heat and bioenergy. If solar power is used as a heat source, regular solar mirrors and solar dishes may be utilised. The use of Fresnel lenses and mirrors has also been advocated, for example in planetary surface exploration. Solar powered Stirling engines are increasingly popular as they offer an environmentally sound option for producing power while some designs are economically attractive in development projects.
Heat exchangers
Designing Stirling engine heat exchangers is a balance between high heat transfer with low viscous pumping losses, and low dead space (unswept internal volume). Engines that operate at high powers and pressures require that heat exchangers on the hot side be made of alloys that retain considerable strength at high temperatures and that don't corrode or creep.
In small, low power engines the heat exchangers may simply consist of the walls of the respective hot and cold chambers, but where larger powers are required a greater surface area is needed to transfer sufficient heat. Typical implementations are internal and external fins or multiple small bore tubes for the hot side, and a cooler using a liquid (like water) for the cool side.
Regenerator
In a Stirling engine, the regenerator is an internal heat exchanger and temporary heat store placed between the hot and cold spaces such that the working fluid passes through it first in one direction then the other, taking heat from the fluid in one direction, and returning it in the other. It can be as simple as metal mesh or foam, and benefits from high surface area, high heat capacity, low conductivity and low flow friction. Its function is to retain within the system that heat which would otherwise be exchanged with the environment at temperatures intermediate to the maximum and minimum cycle temperatures, thus enabling the thermal efficiency of the cycle (though not of any practical engine) to approach the limiting Carnot efficiency.
The primary effect of regeneration in a Stirling engine is to increase the thermal efficiency by 'recycling' internal heat which would otherwise pass through the engine irreversibly. As a secondary effect, increased thermal efficiency yields a higher power output from a given set of hot and cold end heat exchangers. These usually limit the engine's heat throughput. In practice this additional power may not be fully realized as the additional "dead space" (unswept volume) and pumping loss inherent in practical regenerators reduces the potential efficiency gains from regeneration.
The design challenge for a Stirling engine regenerator is to provide sufficient heat transfer capacity without introducing too much additional internal volume ('dead space') or flow resistance. These inherent design conflicts are one of many factors that limit the efficiency of practical Stirling engines. A typical design is a stack of fine metal wire meshes, with low porosity to reduce dead space, and with the wire axes perpendicular to the gas flow to reduce conduction in that direction and to maximize convective heat transfer.
The regenerator is the key component invented by Robert Stirling, and its presence distinguishes a true Stirling engine from any other closed-cycle hot air engine. Many small 'toy' Stirling engines, particularly low-temperature difference (LTD) types, do not have a distinct regenerator component and might be considered hot air engines; however, a small amount of regeneration is provided by the surface of the displacer itself and the nearby cylinder wall, or similarly the passage connecting the hot and cold cylinders of an alpha configuration engine.
Heat sink
The larger the temperature difference between the hot and cold sections of a Stirling engine, the greater the engine's efficiency. The heat sink is typically the environment the engine operates in, at ambient temperature. In the case of medium- to high-power engines, a radiator is required to transfer the heat from the engine to the ambient air. Marine engines have the advantage of using cool ambient sea, lake, or river water, which is typically cooler than ambient air. In the case of combined heat and power systems, the engine's cooling water is used directly or indirectly for heating purposes, raising efficiency.
Alternatively, heat may be supplied at ambient temperature and the heat sink maintained at a lower temperature by such means as cryogenic fluid (see Liquid nitrogen economy) or iced water.
Displacer
The displacer is a special-purpose piston, used in Beta and Gamma type Stirling engines, to move the working gas back and forth between the hot and cold heat exchangers. Depending on the type of engine design, the displacer may or may not be sealed to the cylinder; i.e., it may be a loose fit within the cylinder, allowing the working gas to pass around it as it moves to occupy the part of the cylinder beyond. The Alpha type engine has a high stress on the hot side, that's why so few inventors started to use a hybrid piston for that side. The hybrid piston has a sealed part as a normal Alpha type engine, but it has a connected displacer part with smaller diameter as the cylinder around that. The compression ratio is a bit smaller than in the original Alpha type engines, but the stress factor is pretty low on the sealed parts.
Configurations
The three major types of Stirling engines are distinguished by the way they move the air between the hot and cold areas:
The alpha configuration has two power pistons, one in a hot cylinder, one in a cold cylinder, and the gas is driven between the two by the pistons; it is typically in a V-formation with the pistons joined at the same point on a crankshaft.
The beta configuration has a single cylinder with a hot end and a cold end, containing a power piston and a 'displacer' that drives the gas between the hot and cold ends. It is typically used with a rhombic drive to achieve the phase difference between the displacer and power pistons, but they can be joined 90 degrees out of phase on a crankshaft.
The gamma configuration has two cylinders: one containing a displacer, with a hot and a cold end, and one for the power piston; they are joined to form a single space, so the cylinders have equal pressure; the pistons are typically in parallel and joined 90 degrees out of phase on a crankshaft.
Alpha
An alpha Stirling contains two power pistons in separate cylinders, one hot and one cold. The hot cylinder is situated inside the high-temperature heat exchanger and the cold cylinder is situated inside the low-temperature heat exchanger. This type of engine has a high power-to-volume ratio but has technical problems because of the usually high temperature of the hot piston and the durability of its seals. In practice, this piston usually carries a large insulating head to move the seals away from the hot zone at the expense of some additional dead space. The crank angle has a major effect on efficiency and the best angle frequently must be found experimentally. An angle of 90° frequently locks.
A four-step description of the process is as follows:
Most of the working gas is in the hot cylinder and has more contact with the hot cylinder's walls. This results in overall heating of the gas. Its pressure increases and the gas expands. Because the hot cylinder is at its maximum volume and the cold cylinder is at mid stroke (partial volume), the volume of the system is increased by expansion into the cold cylinder.
The system is at its maximum volume and more gas has contact with the cold cylinder. This cools the gas, lowering its pressure. Because of flywheel momentum or other piston pairs on the same shaft, the hot cylinder begins an upstroke reducing the volume of the system.
Almost all the gas is now in the cold cylinder and cooling continues. This continues to reduce the pressure of the gas and cause contraction. Because the hot cylinder is at minimum volume and the cold cylinder is at its maximum volume, the volume of the system is further reduced by compression of the cold cylinder inwards.
The system is at its minimum volume and the gas has greater contact with the hot cylinder. The volume of the system increases by expansion of the hot cylinder.
Beta
A beta Stirling has a single power piston arranged within the same cylinder on the same shaft as a displacer piston. The displacer piston is a loose fit and does not extract any power from the expanding gas but only serves to shuttle the working gas between the hot and cold heat exchangers. When the working gas is pushed to the hot end of the cylinder it expands and pushes the power piston. When it is pushed to the cold end of the cylinder it contracts and the momentum of the machine, usually enhanced by a flywheel, pushes the power piston the other way to compress the gas. Unlike the alpha type, the beta type avoids the technical problems of hot moving seals, as the power piston is not in contact with the hot gas.
Power piston (dark grey) has compressed the gas, the displacer piston (light grey) has moved so that most of the gas is adjacent to the hot heat exchanger.
The heated gas increases in pressure and pushes the power piston to the farthest limit of the power stroke.
The displacer piston now moves, shunting the gas to the cold end of the cylinder.
The cooled gas is now compressed by the flywheel momentum. This takes less energy, since its pressure drops when it is cooled.
Gamma
A gamma Stirling is simply a beta Stirling with the power piston mounted in a separate cylinder alongside the displacer piston cylinder, but still connected to the same flywheel. The gas in the two cylinders can flow freely between them and remains a single body. This configuration produces a lower compression ratio because of the volume of the connection between the two but is mechanically simpler and often used in multi-cylinder Stirling engines.
Other types
Other Stirling configurations continue to interest engineers and inventors.
The rotary Stirling engine seeks to convert power from the Stirling cycle directly into torque, similar to the rotary combustion engine. No practical engine has yet been built but a number of concepts, models and patents have been produced, such as the Quasiturbine engine.
A hybrid between piston and rotary configuration is a double-acting engine. This design rotates the displacers on either side of the power piston. In addition to giving great design variability in the heat transfer area, this layout eliminates all but one external seal on the output shaft and one internal seal on the piston. Also, both sides can be highly pressurized as they balance against each other.
Another alternative is the Fluidyne engine (or Fluidyne heat pump), which uses hydraulic pistons to implement the Stirling cycle. The work produced by a Fluidyne engine goes into pumping the liquid. In its simplest form, the engine contains a working gas, a liquid, and two non-return valves.
The Ringbom engine concept published in 1907 has no rotary mechanism or linkage for the displacer. This is instead driven by a small auxiliary piston, usually a thick displacer rod, with the movement limited by stops.
The engineer Andy Ross invented a two-cylinder Stirling engine (positioned at 0°, not 90°) connected using a special yoke.
The Franchot engine is a double-acting engine invented by Charles-Louis-Félix Franchot in the nineteenth century. In a double-acting engine, the pressure of the working fluid acts on both sides of the piston. One of the simplest forms of a double-acting machine, the Franchot engine consists of two pistons and two cylinders, and acts like two separate alpha machines. In the Franchot engine, each piston acts in two gas phases, which makes more efficient use of the mechanical components than a single-acting alpha machine. However, a disadvantage of this machine is that one connecting rod must have a sliding seal at the hot side of the engine, which is difficult when dealing with high pressures and temperatures.
Free-piston engines
Free-piston Stirling engines include those with liquid pistons and those with diaphragms as pistons. In a free-piston device, energy may be added or removed by an electrical linear alternator, pump or other coaxial device. This avoids the need for a linkage, and reduces the number of moving parts. In some designs, friction and wear are nearly eliminated by the use of non-contact gas bearings or very precise suspension through planar springs.
Four basic steps in the cycle of a free-piston Stirling engine are:
The power piston is pushed outwards by the expanding gas thus doing work. Gravity plays no role in the cycle.
The gas volume in the engine increases and therefore the pressure reduces, which causes a pressure difference across the displacer rod to force the displacer towards the hot end. When the displacer moves, the piston is almost stationary and therefore the gas volume is almost constant. This step results in the constant volume cooling process, which reduces the pressure of the gas.
The reduced pressure now arrests the outward motion of the piston and it begins to accelerate towards the hot end again and by its own inertia, compresses the now cold gas, which is mainly in the cold space.
As the pressure increases, a point is reached where the pressure differential across the displacer rod becomes large enough to begin to push the displacer rod (and therefore also the displacer) towards the piston and thereby collapsing the cold space and transferring the cold, compressed gas towards the hot side in an almost constant volume process. As the gas arrives in the hot side the pressure increases and begins to move the piston outwards to initiate the expansion step as explained in (1).
In the early 1960s, William T. Beale of Ohio University located in Athens, Ohio, invented a free piston version of the Stirling engine to overcome the difficulty of lubricating the crank mechanism. While the invention of the basic free piston Stirling engine is generally attributed to Beale, independent inventions of similar types of engines were made by E.H. Cooke-Yarborough and C. West at the Harwell Laboratories of the UK AERE. G.M. Benson also made important early contributions and patented many novel free-piston configurations.
The first known mention of a Stirling cycle machine using freely moving components is a British patent disclosure in 1876. This machine was envisaged as a refrigerator (i.e., the reversed Stirling cycle). The first consumer product to utilize a free piston Stirling device was a portable refrigerator manufactured by Twinbird Corporation of Japan and offered in the US by Coleman in 2004.
Flat engines
Design of the flat double-acting Stirling engine solves the drive of a displacer with the help of the fact that areas of the hot and cold pistons of the displacer are different.
The drive does so without any mechanical transmission. Using diaphragms eliminates friction and need for lubricants.
When the displacer is in motion, the generator holds the working piston in the limit position, which brings the engine working cycle close to an ideal Stirling cycle.
The ratio of the area of the heat exchangers to the volume of the machine increases by the implementation of a flat design.
Flat design of the working cylinder approximates thermal process of the expansion and compression closer to the isothermal one.
The disadvantage is a large area of the thermal insulation between the hot and cold space.
Thermoacoustic cycle
Thermoacoustic devices are very different from Stirling devices, although the individual path travelled by each working gas molecule does follow a real Stirling cycle. These devices include the thermoacoustic engine and thermoacoustic refrigerator. High-amplitude acoustic standing waves cause compression and expansion analogous to a Stirling power piston, while out-of-phase acoustic travelling waves cause displacement along a temperature gradient, analogous to a Stirling displacer piston. Thus a thermoacoustic device typically does not have a displacer, as found in a beta or gamma Stirling.
Other developments
NASA has considered nuclear-decay heated Stirling Engines for extended missions to the outer solar system. In 2018, NASA and the United States Department of Energy announced that they had successfully tested a new type of nuclear reactor called KRUSTY, which stands for "Kilopower Reactor Using Stirling TechnologY", and which is designed to be able to power deep space vehicles and probes as well as exoplanetary encampments.
At the 2012 Cable-Tec Expo put on by the Society of Cable Telecommunications Engineers, Dean Kamen took the stage with Time Warner Cable Chief Technology Officer Mike LaJoie to announce a new initiative between his company Deka Research and the SCTE. Kamen refers to it as a Stirling engine.
Operational considerations
Size and temperature
Very low-power engines have been built that run on a temperature difference of as little as 0.5 K. A displacer-type Stirling engine has one piston and one displacer. A temperature difference is required between the top and bottom of the large cylinder to run the engine. In the case of the low-temperature-difference (LTD) Stirling engine, the temperature difference between one's hand and the surrounding air can be enough to run the engine. The power piston in the displacer-type Stirling engine is tightly sealed and is controlled to move up and down as the gas inside expands. The displacer, on the other hand, is very loosely fitted so that air can move freely between the hot and cold sections of the engine as the piston moves up and down. The displacer moves up and down to cause most of the gas in the displacer cylinder to be either heated, or cooled.
Stirling engines, especially those that run on small temperature differentials, are quite large for the amount of power that they produce (i.e., they have low specific power). This is primarily due to the heat transfer coefficient of gaseous convection, which limits the heat flux that can be attained in a typical cold heat exchanger to about 500 W/(m2·K), and in a hot heat exchanger to about 500–5000 W/(m2·K). Compared with internal combustion engines, this makes it more challenging for the engine designer to transfer heat into and out of the working gas. Because of the thermal efficiency the required heat transfer grows with lower temperature difference, and the heat exchanger surface (and cost) for 1 kW output grows with (1/ΔT)2. Therefore, the specific cost of very low temperature difference engines is very high. Increasing the temperature differential and/or pressure allows Stirling engines to produce more power, assuming the heat exchangers are designed for the increased heat load, and can deliver the convected heat flux necessary.
A Stirling engine cannot start instantly; it literally needs to "warm up". This is true of all external combustion engines, but the warm up time may be longer for Stirlings than for others of this type such as steam engines. Stirling engines are best used as constant speed engines.
Power output of a Stirling tends to be constant and to adjust it can sometimes require careful design and additional mechanisms. Typically, changes in output are achieved by varying the displacement of the engine (often through use of a swashplate crankshaft arrangement), or by changing the quantity of working fluid, or by altering the piston/displacer phase angle, or in some cases simply by altering the engine load. This property is less of a drawback in hybrid electric propulsion or "base load" utility generation where constant power output is actually desirable.
Gas choice
The gas used should have a low heat capacity, so that a given amount of transferred heat leads to a large increase in pressure. Considering this issue, helium would be the best gas because of its very low heat capacity. Air is a viable working fluid, but the oxygen in a highly pressurized air engine can cause fatal accidents caused by lubricating oil explosions. Following one such accident Philips pioneered the use of other gases to avoid such risk of explosions.
Hydrogen's low viscosity and high thermal conductivity make it the most powerful working gas, primarily because the engine can run faster than with other gases. However, because of hydrogen absorption, and given the high diffusion rate associated with this low molecular weight gas, particularly at high temperatures, H2 leaks through the solid metal of the heater. Diffusion through carbon steel is too high to be practical, but may be acceptably low for metals such as aluminum, or even stainless steel. Certain ceramics also greatly reduce diffusion. Hermetic pressure vessel seals are necessary to maintain pressure inside the engine without replacement of lost gas. For high-temperature-differential (HTD) engines, auxiliary systems may be required to maintain high-pressure working fluid. These systems can be a gas storage bottle or a gas generator. Hydrogen can be generated by electrolysis of water, the action of steam on red hot carbon-based fuel, by gasification of hydrocarbon fuel, or by the reaction of acid on metal. Hydrogen can also cause the embrittlement of metals. Hydrogen is a flammable gas, which is a safety concern if released from the engine.
Most technically advanced Stirling engines, like those developed for United States government labs, use helium as the working gas, because it functions close to the efficiency and power density of hydrogen with fewer of the material containment issues. Helium is inert, and hence not flammable. Helium is relatively expensive, and must be supplied as bottled gas. One test showed hydrogen to be 5% (absolute) more efficient than helium (24% relatively) in the GPU-3 Stirling engine. The researcher Allan Organ demonstrated that a well-designed air engine is theoretically just as efficient as a helium or hydrogen engine, but helium and hydrogen engines are several times more powerful per unit volume.
Some engines use air or nitrogen as the working fluid. These gases have much lower power density (which increases engine costs), but they are more convenient to use and they minimize the problems of gas containment and supply (which decreases costs). The use of compressed air in contact with flammable materials or substances such as lubricating oil introduces an explosion hazard, because compressed air contains a high partial pressure of oxygen. However, oxygen can be removed from air through an oxidation reaction or bottled nitrogen can be used, which is nearly inert and very safe.
Other possible lighter-than-air gases include methane, and ammonia.
Pressurization
In most high-power Stirling engines, both the minimum pressure and mean pressure of the working fluid are above atmospheric pressure. This initial engine pressurization can be realized by a pump, or by filling the engine from a compressed gas tank, or even just by sealing the engine when the mean temperature is lower than the mean operating temperature. All of these methods increase the mass of working fluid in the thermodynamic cycle. All of the heat exchangers must be sized appropriately to supply the necessary heat transfer rates. If the heat exchangers are well designed and can supply the heat flux needed for convective heat transfer, then the engine, in a first approximation, produces power in proportion to the mean pressure, as predicted by the West number, and Beale number. In practice, the maximum pressure is also limited to the safe pressure of the pressure vessel. Like most aspects of Stirling engine design, optimization is multivariate, and often has conflicting requirements. A difficulty of pressurization is that while it improves the power, the heat required increases proportionately to the increased power. This heat transfer is made increasingly difficult with pressurization since increased pressure also demands increased thicknesses of the walls of the engine, which, in turn, increase the resistance to heat transfer.
Lubricants and friction
At high temperatures and pressures, the oxygen in air-pressurized crankcases, or in the working gas of hot air engines, can combine with the engine's lubricating oil and explode. At least one person has died in such an explosion. Lubricants can also clog heat exchangers, especially the regenerator. For these reasons, designers prefer non-lubricated, low-coefficient of friction materials (such as rulon or graphite), with low normal forces on the moving parts, especially for sliding seals. Some designs avoid sliding surfaces altogether by using diaphragms for sealed pistons. These are some of the factors that allow Stirling engines to have lower maintenance requirements and longer life than internal-combustion engines.
Efficiency
Theoretical thermal efficiency equals that of the hypothetical Carnot cycle, i.e. the highest efficiency attainable by any heat engine. However, though it is useful for illustrating general principles, the ideal cycle deviates substantially from practical Stirling engines. It has been argued that its indiscriminate use in many standard books on engineering thermodynamics has done a disservice to the study of Stirling engines in general.
Stirling engines cannot achieve total efficiencies typical of an internal combustion engine, the main constraint being thermal efficiency. During internal combustion, temperatures achieve around 1500 °C–1600 °C for a short period of time, resulting in greater mean heat supply temperature of the thermodynamic cycle than any Stirling engine could achieve. It is not possible to supply heat at temperatures that high by conduction, as it is done in Stirling engines because no material could conduct heat from combustion in that high temperature without huge heat losses and problems related to heat deformation of materials.
Stirling engines are capable of quiet operation and can use almost any heat source. The heat energy source is generated external to the Stirling engine rather than by internal combustion as with the Otto cycle or Diesel cycle engines. This type of engine is currently generating interest as the core component of micro combined heat and power (CHP) units, in which it is more efficient and safer than a comparable steam engine. However, it has a low power-to-weight ratio, rendering it more suitable for use in static installations where space and weight are not at a premium.
Other real-world issues reduce the efficiency of actual engines, due to the limits of convective heat transfer and viscous flow (friction). There are also practical, mechanical considerations: for instance, a simple kinematic linkage may be favoured over a more complex mechanism needed to replicate the idealized cycle, and limitations imposed by available materials such as non-ideal properties of the working gas, thermal conductivity, tensile strength, creep, rupture strength, and melting point. A question that often arises is whether the ideal cycle with isothermal expansion and compression is in fact the correct ideal cycle to apply to the Stirling engine. Professor C. J. Rallis has pointed out that it is very difficult to imagine any condition where the expansion and compression spaces may approach isothermal behavior and it is far more realistic to imagine these spaces as adiabatic. An ideal analysis where the expansion and compression spaces are taken to be adiabatic with isothermal heat exchangers and perfect regeneration was analyzed by Rallis and presented as a better ideal yardstick for Stirling machinery. He called this cycle the 'pseudo-Stirling cycle' or 'ideal adiabatic Stirling cycle'. An important consequence of this ideal cycle is that it does not predict Carnot efficiency. A further conclusion of this ideal cycle is that maximum efficiencies are found at lower compression ratios, a characteristic observed in real machines. In an independent work, T. Finkelstein also assumed adiabatic expansion and compression spaces in his analysis of Stirling machinery
The ideal Stirling cycle is unattainable in the real world, as with any heat engine. The efficiency of Stirling machines is also linked to the environmental temperature: higher efficiency is obtained when the weather is cooler, thus making this type of engine less attractive in places with warmer climates. As with other external combustion engines, Stirling engines can use heat sources other than the combustion of fuels. For example, various designs for solar-powered Stirling engines have been developed.
Comparison with internal combustion engines
In contrast to internal combustion engines, Stirling engines have the potential to use renewable heat sources more easily, and to be quieter and more reliable with lower maintenance. They are preferred for applications that value these unique advantages, particularly if the cost per unit energy generated is more important than the capital cost per unit power. On this basis, Stirling engines are cost-competitive up to about 100 kW.
Compared to an internal combustion engine of the same power rating, Stirling engines currently have a higher capital cost and are usually larger and heavier. However, they are more efficient than most internal combustion engines. Their lower maintenance requirements make the overall energy cost comparable. The thermal efficiency is also comparable (for small engines), ranging from 15% to 30%. For applications such as micro-CHP, a Stirling engine is often preferable to an internal combustion engine. Other applications include water pumping, astronautics, and electrical generation from plentiful energy sources that are incompatible with the internal combustion engine, such as solar energy, and biomass such as agricultural waste and other waste such as domestic refuse. However, Stirling engines are generally not price-competitive as an automobile engine, because of high cost per unit power, & low power density.
Basic analysis is based on the closed-form Schmidt analysis.
Advantages of Stirling engines compared to internal combustion engines include:
Stirling engines can run directly on any available heat source, not just one produced by combustion, so they can run on heat from solar, geothermal, biological, nuclear sources or waste heat from industrial processes.
A continuous combustion process can be used to supply heat, so those emissions associated with the intermittent combustion processes of a reciprocating internal combustion engine can be reduced.
Some types of Stirling engines have the bearings and seals on the cool side of the engine, where they require less lubricant and last longer than equivalents on other reciprocating engine types.
The engine mechanisms are in some ways simpler than other reciprocating engine types. No valves are needed, and the burner system can be relatively simple. Crude Stirling engines can be made using common household materials.
A Stirling engine uses a single-phase working fluid that maintains an internal pressure close to the design pressure, and thus for a properly designed system the risk of explosion is low. In comparison, a steam engine uses a two-phase gas/liquid working fluid, so a faulty overpressure relief valve can cause an explosion.
In some cases, low operating pressure allows the use of lightweight cylinders.
They can be built to run quietly and without an air supply, for air-independent propulsion use in submarines.
They start easily (albeit slowly, after warmup) and run more efficiently in cold weather, in contrast to the internal combustion, which starts quickly in warm weather, but not in cold weather.
A Stirling engine used for pumping water can be configured so that the water cools the compression space. This increases efficiency when pumping cold water.
They are extremely flexible. They can be used as CHP (combined heat and power) in the winter and as coolers in summer.
Waste heat is easily harvested (compared to waste heat from an internal combustion engine), making Stirling engines useful for dual-output heat and power systems.
In 1986 NASA built a Stirling automotive engine and installed it in a Chevrolet Celebrity. Fuel economy was improved 45% and emissions were greatly reduced. Acceleration (power response) was equivalent to the standard internal combustion engine. This engine, designated the Mod II, also nullifies arguments that Stirling engines are heavy, expensive, unreliable, and demonstrate poor performance. A catalytic converter, muffler and frequent oil changes are not required.
Disadvantages of Stirling engines compared to internal combustion engines include:
Stirling engine designs require heat exchangers for heat input and for heat output, and these must contain the pressure of the working fluid, where the pressure is proportional to the engine power output. In addition, the expansion-side heat exchanger is often at very high temperature, so the materials must resist the corrosive effects of the heat source, and have low creep. Typically these material requirements substantially increase the cost of the engine. The materials and assembly costs for a high-temperature heat exchanger typically accounts for 40% of the total engine cost.
All thermodynamic cycles require large temperature differentials for efficient operation. In an external combustion engine, the heater temperature always equals or exceeds the expansion temperature. This means that the metallurgical requirements for the heater material are very demanding. This is similar to a Gas turbine, but is in contrast to an Otto engine or Diesel engine, where the expansion temperature can far exceed the metallurgical limit of the engine materials, because the input heat source is not conducted through the engine, so engine materials operate closer to the average temperature of the working gas. The Stirling cycle is not actually achievable, the real cycle in Stirling machines is less efficient than the theoretical Stirling cycle, also the efficiency of the Stirling cycle is lower where the ambient temperatures are mild, while it would give its best results in a cool environment, such as northern countries' winters.
Dissipation of waste heat is especially complicated because the coolant temperature is kept as low as possible to maximize thermal efficiency. This increases the size of the radiators, which can make packaging difficult. Along with materials cost, this has been one of the factors limiting the adoption of Stirling engines as automotive prime movers. For other applications such as ship propulsion and stationary microgeneration systems using combined heat and power (CHP) high power density is not required.
Applications
Applications of the Stirling engine range from heating and cooling to underwater power systems. A Stirling engine can function in reverse as a heat pump for heating or cooling. Other uses include combined heat and power, solar power generation, Stirling cryocoolers, heat pump, marine engines, low power model aircraft engines, and low temperature difference engines.
See also
Bore
Distributed generation
Francis Herbert Wenham
John Ericsson
Cost of electricity by source
Schmidt number#Stirling engines
Stroke
Thermomechanical generator
References
Bibliography
E.H. Cooke-Yarborough (1970). "Heat Engines", US patent 3548589. Granted to Atomic Energy Authority UK, 22 December 1970.
E.H. Cooke-Yarborough (1967). "A Proposal for a Heat-Powered Nonrotating Electrical Alternator", Harwell Memorandum AERE-M881.
Further reading
W.T. Beale (1971). "Stirling Cycle Type Thermal Device", US patent 3552120. Granted to Research Corp, 5 January 1971.
R.C. Belaire (1977). "Device for decreasing the start-up time for stirling engines", US patent 4057962. Granted to Ford Motor Company, 15 November 1977.
C.D. West (1970). "Hydraulic Heat Engines", Harwell Momorandum AERE-R6522.
External links
How Stirling Engines Work (YouTube video)
How Beta-type Stirling Engines Work (YouTube video)
Stirling Cycle Machine Analysis by Israel Urieli
How to build your Stirling engine (2017). Stirling Engines: Design and Fabrication
Simple Performance Prediction Method for Stirling Engine
Inquiry into the Hot Air Engines of the 19th Century
Cooling technology
Heat pumps
Hot air engines
Piston engines
Scottish inventions
Articles containing video clips
External combustion engines | wiki |
Xaero may refer to:
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Quake III Arena | wiki |
In United States business law, a registered agent (also known as a resident agent, statutory agent, or agent for service of process) is a business or individual designated to receive service of process (SOP) when a business entity is a party in a legal action such as a lawsuit or summons. The registered agent's address may also be where the state sends the paperwork for the periodic renewal of the business entity's charter (if required). The registered agent for a business entity may be an officer or employee of the company, or a third party, such as the organization's lawyer or a service company. Failure to properly maintain a registered agent can affect a company negatively.
Services provided
Most businesses are not individuals but instead business entities such as corporations or limited liability companies (LLCs). This is because there are substantive (and substantial) liability protections as well as tax advantages to being "incorporated" as opposed to being "self-employed".
If a registered agent fails to perform their function, it can have dire consequences for the business entity. For example, if a customer fell inside a store and sued the store, and the store's registered agent failed to notify the business entity of a summons to appear in court to respond to the lawsuit, then when the case went to trial, nobody would appear to defend the store and the customer would win by a default judgment. Additionally, the store would likely not be able to get the judgment overturned on appeal because they had been properly served. This is one of the most common reasons that business entities generally will utilize a third party as their registered agent be it a commercial service company, an attorney, or in some cases, a CPA.
The person at a business entity that maintains contact with the registered agent is normally the corporate secretary or governance officer.
Designation
A registered agent is designated by a business entity by completing a form and filing it with the appropriate government agency, normally a state's Secretary of State's office.
Initial designation
In most all cases, the registered agent for a business entity is assigned in the formation documents filed in a jurisdiction when the entity is originally created. For example, a person forming a corporation in the State of Nevada or Delaware, would designate the registered agent along with the agent's address on the articles of incorporation filed with the Nevada Secretary of State or Delaware Secretary of State respectively. If the agent cannot sign the articles to be filed, some states such as Nevada provide that the registered agent may be designated using a separate "Registered Agent Acceptance" form with the appropriate acceptance and signature. A representative of the business or the individual accepting responsibility as registered agent must sign to accept the responsibility of acting as agent. In most states it is a crime to knowingly file a false document with the office of the Secretary of State, although the penalties vary widely. For example, in Nevada it is a Class "D" felony to forge this signature, but in Michigan it is only a misdemeanor.
Change of agent
A business entity might at some point want to change its previously designated registered agent to another party. This is accomplished by obtaining a form from the secretary of state where the business entity is registered, completing said form, and filing it with that state office along with any requisite fees which may vary from state to state. In some cases the required form may simply be a dedicated change of registered agent form, and in other cases, such as in Delaware, an actual amendment to the articles of the business entity must be filed.
Locating registered agents
Information about persons or entities that are available to act as registered agents in a given state may be maintained by the state's Secretary of State office. Most states also offer free online database searches to identify a business entity's registered agent.
Some state business entity laws name the Secretary of State's office or business entity filing office as the registered agent of last resort, in the event the named registered agent can't be found. By law, service may be made on the office if the entities registered agent can not be found. However, the plaintiff must demonstrate that it made a good faith effort to service the registered agent before it may serve the Secretary of State. The state laws vary in how to complete service on the Secretary of State and the amount of fees charged. Some of the states that may have this statutory provision are listed below. MoRAA eliminated this provision but some of the states that adopted MoRAA maintained this provision.
Regulation
Most jurisdictions in the United States require that any business entity that is formed or doing business within their borders designate and maintain a "registered agent". This person may be known as the "resident agent" or "statutory agent", depending on the laws of the individual jurisdiction in which the business entity is registered. The purpose of a registered agent is to provide a legal address (not a P.O. Box) within that jurisdiction where there are persons available during normal business hours to facilitate legal service of process being served in the event of a legal action or lawsuit. Generally, the registered agent is also the person to whom the state government sends all official documents required each year for tax and legal purposes, such as franchise tax notices and annual report forms. It is the registered agent's job to forward these suit documents and notices to the entity itself. Registered agents generally will also notify business entities if their state government filing status is in "good standing" or not. The reason that these notifications are a desired function of a registered agent is that it is difficult for a business entity to keep track of legislative changes and report due dates for multiple jurisdictions given the disparate laws of different states.
The failure to maintain a registered agent may cause a jurisdiction to revoke a business's corporate or LLC legal status, imposition of penalty fees on the entity, or both.
Who may serve as a registered agent
Different states have different requirements for registered agents. Typically, the agent must be a natural person resident of the state in question or, in states that allow entities to serve as registered agents, an entity having a business office within the state and authorized to do business in the state. In some states a business entity is legally allowed to act as its own registered agent, if at least one of its officers is a resident of the state, but other jurisdictions may require that a business entity designate a third party as its registered agent.
Because most states permit one business entity to serve as a registered agent for others, some businesses exist to serve that exact function, charging a fee to act as the registered agent for hundreds or thousands of businesses in a given state.
Model Registered Agents Act
The Model Registered Agents Act (MoRAA) is an effort spearheaded by the American Bar Association Business Law Section and the International Association of Commercial Administrators (IACA) – Business Organization Section (BOS) to standardize business entity laws as they relate to annual reports, registered agents and other laws and forms used to file business entities. The act also creates two distinct classes of registered agent: "commercial" and "non-commercial." The National Conference of Commissions on Uniform State Laws (NCCUSL) organized a drafting committee composed of commissions, ABA, and IACA representatives who drafted the act's language. NCCUSL adopted MoRAA at its 2006 annual meeting. It was amended in 2011. Eleven US jurisdictions (Arkansas, District of Columbia, Idaho, Maine, Mississippi, Montana, Nevada, North Dakota, South Dakota, Utah, and Wyoming) have since adopted the model act, and Delaware did not adopt the act, but did adopt the "commercial registered agent" provision. The problem this effort seeks to alleviate is that disparate laws, filing requirements, and forms in all of the US jurisdictions where business entities are filed creates a quagmire for any company seeking to register to do business in those jurisdictions. By adopting a common set of laws, the Model Registered Agents Act seeks to create a uniform and simple process of filing and maintaining a business entity in any jurisdiction adopting it.
Alaska
Arkansas
California
Delaware
Idaho
Maine
Mississippi
Montana
Nevada
New Hampshire
North Dakota
Pennsylvania
Wyoming
See also
List of Secretaries of State, who in the United States provide information about available registered agents in each state
References
Agency law
United States business law
Region-specific legal occupations | wiki |
Desmond King is the name of:
Desmond King (American football) (born 1994), American football player
Desmond King (professor) (born 1957), professor
Desmond King-Hele (1927–2019), British physicist and author | wiki |
Section 3 may refer to:
Section 3 of the Canadian Charter of Rights and Freedoms
Section 3 (NYSPHSAA), of the New York State Public High School Athletic Association
Section 3 lands in the United States
Section 3 of the Human Rights Act 1998
Section 3 of the Constitution of Australia
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MI3, British Military Intelligence Section 3 | wiki |
Qatar does not have any permanent rivers, but instead has numerous wadis. Wadis are defined as dry river valleys which experience intermittent water flow during the rainy season.
The Ministry of Municipality and Environment has recorded a total of 306 wadis scattered throughout Qatar.
Some of the most prominent wadis are:
Wadi Asmah
Wadi Al Banat
Wadi Debayan
Wadi Diyab
Wadi Ghirban
Wadi Huwaila
Wadi Lusail
References
Qatar
Valleys | wiki |
Section 4 may refer to:
Section 4 of the Constitution of Australia
Section 4 of the Canadian Charter of Rights and Freedoms
Section 4 of the Human Rights Act 1998
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MI4, British Directorate of Military Intelligence, Section 4 | wiki |
Twopenny may refer to:
the British coin: see History of the British penny (1901–1970)
Richard Twopenny, Australian journalist and journalist
Twopenny (cricketer) (c. 1845 – 1883), the first Aboriginal Australian to play first-class cricket
Twopenny Tube, an underground "tube" railway in London
Two Penny Act, enacted in 1758 by the Virginia General Assembly
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Fivepenny (disambiguation)
Tenpenny (disambiguation) | wiki |
A finger sleeve is worn by certain basketball players to support and protect their fingers, as well as to enhance grip on the ball during a shot. It is the player's preference on which finger the sleeve is worn. Many choose to wear more than one finger sleeve, such as Reggie Miller. The use of the finger sleeve is authorized and approved by the NBA (National Basketball Association).
In many cases the finger sleeve is worn for protection instead of performing some sort of taping job on the digit.
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Monomorium salomonis is a species of ant. It is a pest of millets.
References
salomonis
Ants | wiki |
Simon Wardley is a British researcher and former CEO best known for the creation of Wardley mapping.
References
External links
Map camp website
Simon Wardley on Twitter
Living people
Year of birth missing (living people)
British technology chief executives | wiki |
Water buttercup is a common name for several plants and may refer to:
Ranunculus aquatilis, the white water buttercup
Ranunculus flabellaris, the yellow water buttercup | wiki |
Kim Yu-yeon () may refer to:
Kim Yu-yeon (curator) (born 1956), South Korean curator
Kim Yoo-yeon (born 1982), South Korean sport shooter
Kim Yu-yeon (swimmer) (born 1991), South Korean swimmer | wiki |
The Nokia 2651 is Nokia's first entry level clamshell phone. It was described as a "stylish fold for every occasion and every budget" by Nokia's website. Although quite popular in the Latin American market, no large carriers in the US showed interest and the 2651 made almost no impression on the US market. The European version of this phone is the 2650.
Specifications
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2651 | wiki |
References
Human protein-coding genes 1 | wiki |
Valley Line or Valley Lines may refer to:
Valley Line (Edmonton), a future light rail line in Canada
Valley Lines (train operating company), operating in Wales 1996–2001
Valleys & Cardiff Local Routes, formerly Valley Lines, a rail network radiating from Cardiff, Wales
See also
Thalweg, the line of lowest elevation within a valley or watercourse | wiki |
References
Human protein-coding genes 2 | wiki |
Phrynobatrachus chukuchuku, the spiny puddle frog, is a species of frog in the family Phrynobatrachidae. They are endemic to Cameroon, and considered Critically Endangered.
Taxonomy
The spiny puddle frog was described in 2009 by Breda M. Zimkus. Its specific name, "chukuchuku" comes from a Cameroonian pidgin English phrase meaning "spiny" or "thorny".
Description
Spiny puddle frogs are easily distinguished from other members of their genus due to the unique ventral coloration of the males, a dark black. The females possess a much lighter throat coloration. Females are also larger than males, being an average of 17–19 mm long, while males are closer to 15–16 mm long. The common name of spiny puddle frog comes from the spinules male possess on their undersides.
As tadpoles, spiny puddle frogs range from 6–7 mm long, and have ovoid body shapes. They're dark in coloration.
Habitat and distribution
The spiny puddle frog is only known from grasslands near the summit of Mount Oku in Cameroon. Surveys conducted in the area find them most often frequenting springs and wetlands. Tadpoles are found in slow-moving waters in montane grassland.
History and conservation
Spiny puddle frogs were first discovered in 2006, and were described in 2009. They are threatened by a number of things, including climate change, livestock grazing, fire, and disease. Conservation efforts in the area are scarce, and experts believe that more research needs to be conducted on Mount Oku to determine how to protect its fauna, including the spiny puddle frog, from these threats. The species was added to the IUCN Red List as Critically Endangered in 2011.
References
chukuchuku
Amphibians of Cameroon
Endemic fauna of Cameroon
Amphibians described in 2009 | wiki |
Le terme résistance thermique d’un matériau peut faire référence à :
la résistance thermique, qui qualifie l’opposition à un flux thermique :
résistance thermique de conduction, en conduction thermique,
résistance thermique de convection, en convection,
résistance thermique de rayonnement, en rayonnement thermique,
résistance thermique surfacique, aussi appelée coefficient d’isolation thermique surfacique ;
la résistance (ou tenue) thermique (ou à la chaleur), reliée à la thermostabilité. Voir aussi Matériau réfractaire. | wiki |
A Henley shirt is a collarless pullover shirt, characterized by a round neckline and a placket about long and usually having 2–5 buttons. It essentially is a collarless polo shirt. The sleeves may be either short or long, and it can be made in almost any fabric, although cotton, cotton-polyester blends, and thermals are by far the most popular. Henley shirts are generally regarded as menswear, but women's versions have appeared as business casual and casual wear as well.
History
Henley shirts were named because they were the traditional uniform of rowers in the English town of Henley-on-Thames. The first Henley Royal Regatta was in 1839.
In his biography of Ralph Lauren, the journalist Michael Gross quotes a New York merchant who recalled showing a vintage shirt to a Ralph Lauren buyer: "I showed this fellow underwear—a three-button long-sleeve shirt by Johnstown Knitting Mills. He said, 'This is a new shirt.' That's where he got the idea for the Henley shirt."
References
Shirts
Tops (clothing) | wiki |
The Abney effect or the purity-on-hue effect describes the perceived hue shift that occurs when white light is added to a monochromatic light source.
The addition of white light will cause a desaturation of the monochromatic source, as perceived by the human observer. However, a less intuitive effect of the perceived white light addition is the change in the apparent hue. This hue shift is physiological rather than physical in nature.
This variance of hue as a result of the addition of white light was first described by the English chemist and physicist Sir William de Wiveleslie Abney in 1909, although the date is commonly reported as 1910. A white light source can be created by the combination of red, blue, and green light. Abney demonstrated that the cause of the apparent change in hue was the red and green light that comprised this light source, and that the blue light component had no contribution to the Abney effect.
Chromaticity diagrams
Chromaticity diagrams are two-dimensional diagrams that plot the projection of the International Commission on Illumination (CIE) XYZ color space onto the (x, y) plane. The X, Y, Z values (or tristimulus values) are simply used as weightings to create new colors from the primary colors, much in the same way that RGB is used for creating colors from primaries in televisions or photographs. The x and y values used to create the chromaticity diagram are created from the XYZ values by dividing X and Y by the sum of X, Y, Z. The chromaticity values that can then be plotted are dependent upon two values: dominant wavelength and saturation. Since luminous energy is not included, colors that differ only in its lightness are not distinguished on the diagram. For instance, brown, which is just a low-luminance mixture of orange and red, will not appear as such.
The Abney effect can be illustrated on chromaticity diagrams as well. If one adds white light to a monochromatic light, one will obtain a straight line on the chromaticity diagram. We might imagine that the colors along such a line are all perceived as having the same hue. In reality, this does not hold true, and a hue shift is perceived. Correspondingly, if we plot colors that are perceived as having the same hue (and only differing in purity) we will obtain a curved line.
In chromaticity diagrams, a line that has constant perceived hue must be curved, so that the Abney effect is accounted for. The chromaticity diagrams that have been corrected for the Abney effect are therefore excellent illustrations of the non-linear nature of the visual system. Also, the Abney effect does not disallow any and all straight lines on chromaticity diagrams. One may mix two monochromatic lights and not see a shift in hue, thereby suggesting a straight-line plot for the different levels of mixture would be appropriate on a chromaticity diagram.
Physiology
The opponent process model of the visual system is composed of two chromatic neural channels and one achromatic neural channel. The chromatic channels consist of a red-green channel and a yellow-blue channel and transmit color information. The achromatic channel is responsible for luminance, or white-black discrimination. Hue and saturation are perceived due to varying amounts of activity in these neural channels consisting of axon pathways from retinal ganglion cells. These three channels are tied closely to reaction time in response to colors. The achromatic neural channel has a faster response time than the chromatic neural channels under most conditions. The functions of these channels are task-dependent. Some activities are dependent on one channel or the other, as well as both channels. When a colored stimulus is summed with a white stimulus, both the chromatic and achromatic channels are activated. The achromatic channel will have a slightly slowed response time, since it must adjust to the different luminance; however, despite this delayed response, the speed of the achromatic channel will still be faster than that of the chromatic channel. In these conditions of summed stimuli, the magnitude of the signal emitted by the achromatic channel will be stronger than of the chromatic channel. The coupling of a faster response with a higher amplitude from the achromatic channel means that reaction time will most likely depend on the luminance and saturation levels of the stimuli.
The customary explanations for color vision explain the difference in hue perception as elemental sensations that are inherent to the physiology of the observer. However, no specific physiological constraints or theories have been able to explain the response to each unique hue. To this end, both the observer’s spectral sensitivity and relative number of cone types have proven to not play any significant role in perceiving different hues. Perhaps the environment plays a larger role in the perception of unique hues than the different physiological features across individuals. This is supported by the fact that color judgments can vary depending on differences in the color environment across long periods of time, but these same chromatic and achromatic judgments are held constant if the color environment is the same, despite aging and other individual physiological factors affecting the retina.
Like the Bezold–Brücke effect, the Abney effect suggests a non-linearity between the cone responses (LMS) to the stage of hue perception.
Colorimetric purity
The saturation, or degree of paleness of a color, is related to colorimetric purity. The equation for colorimetric purity is: . In this equation, equals the luminance of the colored light stimulus, is the luminance of the white light stimulus to be mixed with the colored light. The above equation is a way of quantifying the amount of white light that is mixed with the colored light. In the case of pure spectral color, with no white light added, equals one and equals zero. This means colorimetric purity would equal one, and for any case involving the addition of white light, the colorimetric purity, or the value of , would be less than one. The purity of a spectral color stimulus can be altered by adding white, black, or gray stimulus. However, the Abney effect describes the change in colorimetric purity by the addition of white light. In order to determine the effect that changing the purity has on the perceived hue, it is important that purity be the only variable in the experiment; luminance must be kept constant.
Hue discrimination
The term hue discrimination is used to describe the change in wavelength that must be obtained in order for the eye to detect a shift in hue. An expression defines the required wavelength adjustment that must take place. A small (< 2 nm) change in wavelength causes most spectral colors to appear to take on a different hue. However, for blue light and red light, a much larger wavelength shift must occur in order for a person to be able to identify a difference in hue.
History
The original article describing the Abney effect was published by Sir William de Wiveleslie Abney in Proceedings of the Royal Society of London, Series A in December 1909. He decided to do quantitative research following the discovery that the visual observations of color did not match the dominant colors obtained photographically when using models of fluorescence.
A color-measuring apparatus commonly used in experiments in the 1900s was used in conjunction with partially silvered mirrors to split one beam of light into two beams. This resulted in two beams of light parallel to one another having the same intensity and color. The beams of light were projected onto a white background, creating patches of light that were squares. The white light was added to one of the patches of colored light, the patch on the right. A rod was inserted in the path of the two beams so that there would be no space in between the colored surfaces. An additional rod was used to create a shadow where the white light scattered onto the patch that was not to receive addition of white light (the patch on the left side). The amount of white light added was determined as one half of the luminosity of the colored light. The red light source, for example, had more white light added than the yellow light source. He began using two patches of red light, and in fact, the addition of white light to the light patch on the right caused a more yellow tone than the pure red light source. The same results happened when the experimental light source was orange. When the light source was green, the addition of white light caused the appearance of the patch to become yellow-green. Subsequently, when white light was added to yellow-green light, the patch of light appeared primarily yellow. In a mixture of blue-green light (with a slightly higher percentage of blue) with white light, the blue appeared to take on a reddish hue. In the case of a violet light source, the addition of white light caused the violet light to take on a blue tint.
Abney hypothesized that the resulting change in hue that occurred was due to the red light and green light that were components of the white light being added. He also thought that the blue light that also comprises the white light beam was a negligible factor that had no effect on the apparent hue shift. Abney was able to prove his hypothesis experimentally by matching his experimental values of percentage composition and luminosities of red, green, and blue sensations to the calculated values almost exactly. He examined the percentage composition and luminosity found in the different spectral colors as well as the white light source that was added.
Similar effect of bandwidth
While the nonlinearity of neural color-coding, as evidenced by the classical understanding of the Abney effect and its use of white light to particular wavelengths of light, has been thoroughly studied in the past, a new method was undertaken by researchers at the University of Nevada. Rather than adding white light to monochromatic light, the bandwidth of the spectrum was varied. This variation of bandwidth directly targeted the three classes of cone receptors as a means of identifying any hue shifts as perceived by the human eye. The overall goal of the research was to determine whether the appearance of color was affected by the filtering effects of the spectral sensitivity of the eye. Experiments showed that the cone ratios signaled a hue was adjusted so as to produce a constant hue that matched the central wavelength of the light source. Also, the experiments conducted essentially showed that the Abney effect does not hold for all changes in light purity, but is limited very much to certain means of purity degradation, namely the addition of white light. Since the experiments undertaken varied the bandwidth of the light, a similar albeit different means of altering the purity and therefore hue of the monochromatic light, the nonlinearity of the results displayed differently from what had traditionally been seen. Ultimately, the researchers came to the conclusion that variations in spectral bandwidth cause postreceptoral mechanisms to compensate for the filtering effects imposed by cone sensitivities and preretinal absorption and that the Abney effect occurs because the eye has, in a sense, been tricked into seeing a color that would not naturally occur and must therefore approximate the color. This approximation to compensate for the Abney effect is a direct function of the cone excitations experienced with a broadband spectrum.
Miscellaneous facts
A patent for a color printer that claims to compensate for the Abney effect was published in 1995.
The Abney effect must be taken into account when designing the cockpit for modern fighter planes. The colors viewed on the screen become desaturated when white light strikes the screen, so special considerations are made to counteract the Abney effect.
A wide array of spectral colors exist that can be made to exactly match a pure color by adding various levels of white light.
It remains unknown whether the Abney effect is a resulting phenomenon that occurs by chance during color perception or the effect plays a deliberate function in the way the eye codes for color.
Modeling
The Abney effect is rarely described by known color appearance models. Of the many models Fairchild reviewed in Color Appearance Models (3 ed.), only the Hunt and ATD models predict the Abney effect.
See also
Color appearance model
White point
Bezold–Brücke shift
References
Color appearance phenomena | wiki |
Nilgiri Road railway station is a railway station on Kharagpur–Puri line, part of the Howrah–Chennai main line under Kharagpur railway division of South Eastern Railway zone. It is situated at Barunsing, Nilgiri Road in Balasore district in the Indian state of Odisha.
History
In between 1893 and 1896 the East Coast State Railway constructed Howrah–Chennai main line. Kharagpur–Puri branch was finally opened for public in 1901. The route was electrified in several phases. In 2005, Howrah–Chennai route was completely electrified.
References
Railway stations in Balasore district
Kharagpur railway division
Transport in Balasore | wiki |
White wall may refer to:
White Wall (TV drama), a Finnish-Swedish television drama, mystery and sci-fi series
White Wall (Taunus), a prominent rock formation in Hesse
White wall tyre, a fashion in care tyres
The White Wall, a Swedish drama film
White wall (architecture), an aspect of solar architecture | wiki |
Gild may refer to:
Gilding, the application of gold leaf to other material
Guild, an association of craftsmen | wiki |
Jammu and Kashmir may refer to:
Kashmir, the northernmost geographical region of the Indian subcontinent
Jammu and Kashmir (union territory), a region administered by India as a union territory since 2019
Jammu and Kashmir (state), a region administered by India as a state from 1952 to 2019
Jammu and Kashmir (princely state), a princely state of the British Raj extending into the Indian Union between 1846 and 1952
Azad Jammu and Kashmir, or Azad Kashmir, a region administered by Pakistan as an autonomous administrative division
See also
Kashmir conflict
Aksai Chin
Trans-Karakoram Tract
Gilgit-Baltistan
Ladakh
Jammu (disambiguation)
Kashmir (disambiguation) | wiki |
The term Middle English literature refers to the literature written in the form of the English language known as Middle English, from the late 12th century until the 1470s. During this time the Chancery Standard, a form of London-based English became widespread and the printing press regularized the language. Between the 1470s and the middle of the following century there was a transition to early Modern English. In literary terms, the characteristics of the literary works written did not change radically until the effects of the Renaissance and Reformed Christianity became more apparent in the reign of King Henry VIII. There are three main categories of Middle English literature, religious, courtly love, and Arthurian, though much of Geoffrey Chaucer's work stands outside these. Among the many religious works are those in the Katherine Group and the writings of Julian of Norwich and Richard Rolle.
After the Norman conquest of England, Law French became the standard language of courts, parliament, and society. The Norman dialects of the ruling classes mixed with the Anglo-Saxon of the people and became Anglo-Norman, and Anglo-Saxon underwent a gradual transition into Middle English. Around the turn of the thirteenth century, Layamon wrote in Middle English. Other transitional works were popular entertainment, including a variety of romances and lyrics. With time, the English language regained prestige, and in 1362 it replaced French and Latin in Parliament and courts of law. Early examples of Middle English literature are the Ormulum and Havelock the Dane. In the fourteenth century major works of English literature began once again to appear, including the works of Chaucer. The latter portion of the 14th century also saw the consolidation of English as a written language and a shift to secular writing. In the late 15th century William Caxton printed four-fifths of his works in English, which helped to standardize the language and expand the vocabulary.
Early period
After the Norman conquest of England, the written form of the Old English language continued in some monasteries but few literary works are known from this period. Under the influence of the new aristocracy, Law French became the standard language of courts, parliament, and polite society.
As the invaders integrated, their language and literature mingled with that of the natives. The Norman dialects of the ruling classes became Anglo-Norman, and Old English underwent a gradual transition into Middle English. Political power was no longer in English hands, so the West Saxon literary language had no more influence than any other dialect. Middle English literature is written, then, in the many dialects that correspond to the history, culture, and background of the individual writers.
While Anglo-Norman or Latin was preferred for high culture and administration, English literature by no means died out, and a number of important works illustrate the development of the language. Around the turn of the thirteenth century, Layamon wrote his Brut, based on Wace's twelfth century Anglo-Norman epic of the same name. Layamon's language is recognisably Middle English, though his prosody shows a strong Old English influence remaining.
Other transitional works were preserved as popular entertainment, including a variety of romances and lyrics. With time, the English language regained prestige, and in 1362 it replaced French and Latin in Parliament and courts of law. Early examples of Middle English literature are the Ormulum, Havelock the Dane, and Thomas of Hales's Love Rune.
The Mercian dialect thrived between the 8th and 13th centuries and was referred to by John Trevisa, writing in 1387:
"For men of the est with men of the west, as it were undir the same partie of hevene, acordeth more in sownynge of speche than men of the north with men of the south, therefore it is that Mercii, that beeth men of myddel Engelond, as it were parteners of the endes, understondeth better the side langages, northerne and southerne, than northerne and southerne understondeth either other…"
Not much lyrical poetry of the thirteenth century remains, and even fewer secular love poems; "Foweles in the frith" is one exception.
Late period
It was with the fourteenth century that major works of English literature began once again to appear; these include the so-called Pearl Poet's Pearl, Patience, Cleanness, and Sir Gawain and the Green Knight; Langland's political and religious allegory Piers Plowman; John Gower's Confessio Amantis; and the works of Geoffrey Chaucer, the most highly regarded English poet of the Middle Ages, who was seen by his contemporaries as an English successor to the great tradition of Virgil and Dante. Far more manuscripts of the Prick of Conscience than any other Middle English poem survive, however.
The Kildare Poems are a rare example of Middle English literature produced in Ireland, and give an insight into the development of Hiberno-English.
The latter portion of the 14th century also saw not only the consolidation of English as a written language, taking over from French or Latin in certain areas, but a large shift from primarily theological or religious subject matter to also include that of a more secular nature. Vernacular book production saw a growth in the number of books being copied, both secular and religious. Thus, the latter portion of the 14th century can be seen as one of the most significant periods in the history of the English language.
The reputation of Chaucer's successors in the 15th century has suffered in comparison with him, though Lydgate, Thomas Hoccleve, and Skelton are widely studied. At this time the origins of Scottish poetry began with the writing of The Kingis Quair by James I of Scotland. The main poets of this Scottish group were Robert Henryson, William Dunbar, and Gavin Douglas. Henryson and Dunbar introduced a note of almost savage satire, which may have owed something to the Gaelic bardic poetry, while Douglas's version of Virgil's Aeneid is one of the early monuments of Renaissance literary humanism in English.
It was a vibrant time for religious drama as well: many morality plays and miracle plays were produced, and some scripts survive today. Sidrak and Bokkus is another example of late Middle English literature.
Caxton and the English language
In the late 15th century the first English printer, William Caxton, printed four-fifths of his works in English. He translated a large number of works into English; Caxton translated 26 of the titles himself. Caxton is credited with printing as many as 108 books, 87 of which were different titles. However, the English language was changing rapidly in Caxton's time and the works he was given to print were in a variety of styles and dialects. Caxton was a technician rather than a writer and he often faced dilemmas concerning language standardisation in the books he printed. (He wrote about this subject in the preface to his Eneydos.) His successor Wynkyn de Worde faced similar problems.
Caxton is credited with standardising the English language (that is, homogenising regional dialects) through printing. This facilitated the expansion of English vocabulary, the development of inflection and syntax and the ever-widening gap between the spoken and the written word. However, Richard Pynson, a Frenchman who started printing in London in 1491 or 1492 and who favoured Chancery Standard English, was a more accomplished stylist and consequently pushed the English language even further toward standardisation.
See also
Scots makars
English mystery plays
Northern Homily Cycle
When the Nightingale Sings
References
Further reading
Kaiser, Rolf, ed. (1958) Medieval English: an Old English and Middle English anthology; 3rd ed. Berlin: Rolf Kaiser
Literature of England | wiki |
Clifton House may refer to:
United Kingdom
Clifton House, Belfast, a historic building in Northern Ireland
Clifton House, King's Lynn, a grade I listed building in King's Lynn, Norfolk
United States
Clifton House, Pennsylvania, a historic building in Fort Washington, Pennsylvania
Clifton House Site, overnight stop on the Santa Fe Trail
See also
Bullock-Clifton House
Clifton House Preparatory School | wiki |
A publishing contract is a legal contract between a publisher and a writer or author (or more than one), to publish original content by the writer(s) or author(s). This may involve a single written work, or a series of works.
In the case of music publishing, the emphasis is not on printed or recorded works. It usually refers to the promotion of a musical composition, and/or its referral to a suitable recording artist. A music publisher who does produce (or contract to issue) sheet music is known as a music print publisher. It can be used by authors, journalist .etc
Book publishing agreements
Some of the most essential clauses of a standard (boilerplate) book publishing contract are: Grant of Rights, Subsidiary Rights, Delivery and Acceptance, Publication, Copyright, Advance (if there is any), Royalties, and Out of Print. All of them should be taken seriously by authors since trade publishing contracts are not covered in the United States by statutory requirements for fairness and may contain vague language, biased terms and hidden future pitfalls. In the U.K., the Contracts Act of 1999, the Digital Economy Act 2010, and the Enterprise and Regulatory Reform Act of 2013 opened the door to revisions of the established practices in the area of publishing contracts which are currently underway. Therefore,
Types of music publishing agreements
It is important for music authors, producers and publishers to understand the legal rights associated with publishing contracts. The common music publishing contracts are:
(1) Single Song Agreement: A single song deal is an agreement between the writer and the music publisher in which the writer grants certain rights to a publisher for one or more songs. In single song deals, the writer is paid a one-time recoupable advance.
(2) Exclusive Song Writer Agreement ("ESWA") / "Publishing Deal": Under the ESWA or "staff writer" contract, the songwriter generally grants all of the songwriter's share of the income to the music publisher. The writer's services are exclusive to the music publishers for a specified period of time. Thus, any compositions written within that period belong to the music publisher. These deals are usually offered to writers with some degree of success. Because the writer has a track record of writing hits, the publisher feels confident that it will recoup its investment. In return for signing away exclusive rights to some or all the writer's songs, the writer gets paid by the publisher a negotiated advance against future royalties. The advance amount naturally depends on the writer's bargaining power and on the competition in marketplace, if any. Under a staff writer deal, the writer is paid on a weekly or quarterly basis. An ESWA can be either tied to a record contract, or independent of a record contract.
(3) Co-publishing Agreement ("Co-pub"): The co-publishing ("co-pub") deal is perhaps the most common publishing agreement. Under this deal, the songwriter and the music publisher are "co-owners" of the copyrights in the musical compositions. The writer becomes the "co-publisher" (i.e. co-owner) with the music publisher based on an agreed split of the royalties. The songwriter assigns an agreed percentage to the publisher, usually (but not always), a 50/50 split. Thus, the writer conveys _ of the publisher's share to the publisher, but retains all of writer's share. In a typical "75/25 co-pub deal," the writer gets 100% of the songwriter's share, and 50% of the publisher's share, or 75% of the entire copyrights, with the remaining 25% going to the publisher. Thus, when royalties are due and payable, the writer/co-publisher will receive 75% of the income, while the publisher will retain 25%.
-To Understand Deeper
"In royalty payments, there’s a writers share and a publisher’s share. To make things easy, let’s say each share is worth 100%. So the writer has a pie chart of 100% and the publisher has a pie chart of 100%. If there are multiple writers on the track, then they will split the shares accordingly, 50/50 or 25/25/25/25 if there were 4 writers. After the writers share is calculated, you can calculate the publisher’s share or vice versa. A record label would usually own 100% of an artist’s publishing rights, but if you enter into a co-publishing deal, then the label would only get 50% of your publishing. To break it all down, if an artist negotiated a 50/50 split for publishing, and retains 100% of the writers share, then the artist would get half of the publisher’s share and 100% of the writers share. This would be equal to 75% of the total royalty payment. If you publish your own music, this means you get to keep 100% of your royalties..."
(4) Administration Agreement ("Admin"): An administrative agreement takes place between a songwriter/publisher and an independent administrator, or between a writer/publisher and another music publisher. In an "admin deal," the songwriter self-publishes and merely licenses songs to the music publisher for a term of years and for an agreed royalty split. Under this agreement, the music publisher simply administers and exploits the copyrights for another publisher/copyright owner. Only the most popular songwriters can even consider asking for an admin deal. Under this coveted arrangement, ownership of the copyright is usually not transferred to the administrator. Instead, the music publisher gets 10-20% of the gross royalties received from administering and exploiting the songs for a certain period of time and for a certain territory.
(5) Collection Agreement: A collection agreement is like an admin deal where the writer retains the copyrights, except that the publisher does not perform exploitation functions; like an accountant or business manager, it merely collects and disburses available royalty income.
(6) Sub-publishing Agreement: These are basically music publishing deals in foreign territories between a US publisher and a publisher in a foreign territory. They are like admin or collection deals (with no ownership of the copyrights being transferred to the subpublisher), but limited to one or more countries outside the US. Under this publishing deal, the publisher allows the subpublisher to act on its behalf in certain foreign territories. Often, they are limited to a group of countries, such as European Union (EU), GAS (Germany, Austria, Switzerland), Latin America, etc.
(7) 'Purchase Agreement: Under this agreement, one music publisher acquires in whole or in part the catalog of another music publisher, somewhat like a merger of companies. In this case, a "due diligence" investigation is done to determine the value of the catalogue.
(8) Meetings: Meetings are then often arranged to conference about the book. The agreements can be often about the percentage of the money that the Publishers get. Factual MOTs are sometimes set up to bind the LASDs
See also
Publishing
Music publisher (popular music)
References
External links
Book Contract Checklist
Sample Contract Between Author and Publisher
Sample Contract Between Composer and Publisher
Contract law | wiki |
The Convention on the Political Rights of Women was approved by the United Nations General Assembly during the 409th plenary meeting, on 20 December 1952, and adopted on 31 March 1953.
The Convention's purpose is to codify a basic international standard for women's political rights.
Background
In the aftermath of World War II, many countries had still not granted women full political liberty. In 1952, the year before the Convention was adopted, women's suffrage had been granted in less than 100 countries worldwide.
The main impetus for the legislation, and much of its drafting, came from the United Nations Commission on the Status of Women. The Commission sent a survey about women's political rights to its member states; the resulting replies became the basis for the Convention.
The Convention was adopted on 31 March 1953.
Overview
Preamble
The preamble of the Convention reiterates the principles set out in article 21 of the Universal Declaration of Human Rights, which declares that all people have the right to participate in the government of their country, and to access public services. The Convention on the Political Rights of Women specifically protects this right for women.
Articles
The first three articles of the Convention assert the rights of women to vote (Article I), to be eligible for election (II), and to hold public office (III), with each article ending with the specification: "all on equal terms with men, without any discrimination." The remaining articles cover the mechanics of the legislation itself, specifying how and when it will come into force (Articles IV–XI).
Legacy
The Convention entered into force on 7 July 1954. As of August 2015, it has 123 state parties, comprising 122 United Nations member states plus the State of Palestine.
The Convention followed the path of the Inter American Convention on the Granting Political Rights to Women that was the first international legislation at the regional level protecting the equal status of women to exercise political rights. The Convention was the first treaty in the context of the United Nation Moreover, it was the second international treaty to obligate its states to protect citizens' political rights. The Convention was one of the United Nations' several efforts in the postwar period to set standards of nondiscrimination against women; others were the Convention on the Nationality of Married Women and the Convention on Consent to Marriage, Minimum Age for Marriage and Registration of Marriages, brought into force in 1958 and 1964, respectively.
The rights outlined by the Convention were incorporated into the later, more substantial Convention on the Elimination of All Forms of Discrimination Against Women. This later Convention, a wider-reaching and more straightforward legislation for nondiscrimination, was approved by unanimous vote in 1967.
See also
Citizenship
Convention on the Elimination of All Forms of Discrimination Against Women
References
External links
Full text of the Convention on the Political Rights of Women
Signatures and ratifications
Women's rights instruments
Women's suffrage
Treaties entered into force in 1954
Treaties concluded in 1953
Treaties adopted by United Nations General Assembly resolutions
United Nations treaties
Treaties of the Kingdom of Afghanistan
Treaties of the People's Socialist Republic of Albania
Treaties of Algeria
Treaties of the People's Republic of Angola
Treaties of Antigua and Barbuda
Treaties of Argentina
Treaties of Armenia
Treaties of Australia
Treaties of Austria
Treaties of the Bahamas
Treaties of Bangladesh
Treaties of Barbados
Treaties of the Byelorussian Soviet Socialist Republic
Treaties of Belgium
Treaties of Bolivia
Treaties of Bosnia and Herzegovina
Treaties of the Second Brazilian Republic
Treaties of the People's Republic of Bulgaria
Treaties of Burkina Faso
Treaties of Burundi
Treaties of Canada
Treaties of the Central African Republic
Treaties of Chile
Treaties of Colombia
Treaties of the Republic of the Congo
Treaties of Costa Rica
Treaties of Ivory Coast
Treaties of Croatia
Treaties of Cuba
Treaties of Cyprus
Treaties of Czechoslovakia
Treaties of the Czech Republic
Treaties of Zaire
Treaties of Denmark
Treaties of the Dominican Republic
Treaties of Ecuador
Treaties of Egypt
Treaties of El Salvador
Treaties of the Ethiopian Empire
Treaties of Fiji
Treaties of Finland
Treaties of the French Fourth Republic
Treaties of Gabon
Treaties of Georgia (country)
Treaties of East Germany
Treaties of West Germany
Treaties of Ghana
Treaties of the Kingdom of Greece
Treaties of Guatemala
Treaties of Guinea
Treaties of the Hungarian People's Republic
Treaties of Haiti
Treaties of Iceland
Treaties of India
Treaties of Indonesia
Treaties of Ireland
Treaties of Israel
Treaties of Italy
Treaties of Jamaica
Treaties of Jordan
Treaties of Kazakhstan
Treaties of Kyrgyzstan
Treaties of the Kingdom of Laos
Treaties of Latvia
Treaties of Lebanon
Treaties of Lesotho
Treaties of the Libyan Arab Jamahiriya
Treaties of Luxembourg
Treaties of Madagascar
Treaties of Malawi
Treaties of Mali
Treaties of Malta
Treaties of Mauritania
Treaties of Mauritius
Treaties of Mexico
Treaties of the Mongolian People's Republic
Treaties of Montenegro
Treaties of Morocco
Treaties of Nepal
Treaties of the Netherlands
Treaties of New Zealand
Treaties of Nicaragua
Treaties of Niger
Treaties of Nigeria
Treaties of Norway
Treaties of the Dominion of Pakistan
Treaties of the State of Palestine
Treaties of Papua New Guinea
Treaties of Paraguay
Treaties of Peru
Treaties of the Philippines
Treaties of the Polish People's Republic
Treaties of South Korea
Treaties of Moldova
Treaties of the Socialist Republic of Romania
Treaties of the Soviet Union
Treaties of Rwanda
Treaties of Senegal
Treaties of Serbia and Montenegro
Treaties of Yugoslavia
Treaties of Sierra Leone
Treaties of Slovakia
Treaties of Slovenia
Treaties of the Solomon Islands
Treaties of Spain
Treaties of Saint Vincent and the Grenadines
Treaties of Eswatini
Treaties of Sweden
Treaties of Tajikistan
Treaties of Thailand
Treaties of North Macedonia
Treaties of Trinidad and Tobago
Treaties of Tunisia
Treaties of Turkey
Treaties of Turkmenistan
Treaties of Uganda
Treaties of the Ukrainian Soviet Socialist Republic
Treaties of the United Kingdom
Treaties of Tanzania
Treaties of the United States
Treaties of Uzbekistan
Treaties of Venezuela
Treaties of South Yemen
Treaties of Zambia
Treaties of Zimbabwe
1953 in New York City
Treaties extended to Akrotiri and Dhekelia
Treaties extended to Saint Christopher-Nevis-Anguilla
Treaties extended to Bermuda
Treaties extended to the British Antarctic Territory
Treaties extended to the British Indian Ocean Territory
Treaties extended to the British Virgin Islands
Treaties extended to the Cayman Islands
Treaties extended to the Falkland Islands
Treaties extended to Gibraltar
Treaties extended to Guernsey
Treaties extended to the Isle of Man
Treaties extended to Jersey
Treaties extended to Montserrat
Treaties extended to the Pitcairn Islands
Treaties extended to Saint Helena, Ascension and Tristan da Cunha
Treaties extended to South Georgia and the South Sandwich Islands
Treaties extended to the Turks and Caicos Islands
Treaties extended to Greenland
Treaties extended to the Faroe Islands
Treaties extended to Surinam (Dutch colony)
Treaties extended to the British Solomon Islands
Treaties extended to Brunei (protectorate)
Treaties extended to Swaziland (protectorate)
Treaties extended to the Kingdom of Tonga (1900–1970)
Treaties extended to British Hong Kong
Treaties extended to British Antigua and Barbuda
Treaties extended to British Dominica
Treaties extended to British Saint Lucia
Treaties extended to British Saint Vincent and the Grenadines
Treaties extended to British Grenada
Treaties extended to British Honduras
Treaties extended to the Colony of the Bahamas
Treaties extended to West Berlin
1953 in women's history | wiki |
Web scraping, l'extraction du contenu d'un site Web,
Scrappage, une méthode de renaturation de sols par enlèvement d'une couche de terre. | wiki |
The Oxford English Dictionary defines a business manager as "a person who manages the business affairs of an individual, institution, organization, or company".
Compare manager.
Business managers drive the work of others (if any) in order to operate efficiently and (in the case of for-profit companies) to make a profit.
They should have working knowledge of the following areas, and may be a specialist in one or more: finance, marketing and public relations. Other technical areas in which a business manager may have expertise include law, science, and computer programming. In some circumstances, business managers even have oversight over human resources.
Role profile
In many businesses, the role may be established to relieve the owner of responsibility, in order to focus on specific aspects of company expansion. Typically, the business manager and the owner work may work in synergy to ensure successful running of business. Having a specialization in a particular field, such as sales, marketing, public relations or finance aids in efficiency, yet despite the usual academic qualities of a business manager, business managers also develop personal qualities that are helpful in performing the role efficiently.
A social skill of a business manager is the ability to understand and know what each of their subordinate employee's tasks are and how to work with each employee in working toward successful completion of such tasks.
A business manager should be willing to accept constructive criticism from employees, develop social skills, be organized, honest and able to take good decisions. A good business manager should be willing to work along his or her employees in order to create a better work environment.
Examples in industry
In the music industry, a business manager is a representative of musicians or recording artists or both, whose main job is to supervise their business affairs and financial matters. The role largely originated from Allen Klein, who represented numerous performers, helping them to both invest their incomes wisely and to recover unpaid (or underpaid) royalties and fees.
Business managers commonly have an overlapping presence in both the entertainment and sports industries, as illustrated by business manager Barry Klarberg, who represents entertainer Justin Timberlake as well professional athletes C. J. Wilson, Mark Messier and Anna Kournikova.
In government and the military, the equivalent position is executive officer or chief of staff.
See also
Chief executive officer (CEO)
General manager
Product manager
Property manager
Talent manager
Chief of staff
References
Manager
Management occupations
Managers | wiki |
A scroll saw is a small electric or pedal-operated saw used to cut intricate curves in wood, metal, or other materials. The fineness of its blade allows it to cut more delicately than a power jigsaw, and more easily than a hand coping saw or fretsaw. Like those tools, it is capable of creating curves with edges, by pivoting its table.
The scroll saw's name derives from its traditional use in making scrollwork, sculptural ornaments which prominently featured scroll-head designs.
Advantages
While somewhat similar to a band saw, a scroll saw uses a reciprocating blade rather than a continuous loop. Like a hand coping saw, the scroll saw's blade can be removed and placed through a pre-drilled starting hole, allowing interior cutouts to be made without an entry slot. Also, the fineness in both width and tooth count of a scroll's blade permits significantly more intricate curves than even the narrowest gauge band-saw blade.
The majority of scroll saws offer a small light on a flexible arm that illuminates the work area and a dust blower nozzle to keep the work space clear while working. Table-tilting enables angled cuts to be made precisely and easily. Variable-speed support allows even finer control over cuts when working with delicate materials or when making intricate cuts.
Types
Scroll saws are classified according to the size of their throat, which is the distance from the blade to the rear frame of the saw. The throat depth determines how large a piece of wood can be cut. Smaller saws have a throat of as little as , while commercial saws can approach . Before the era of computer automation, industrial saws were sometimes used to make even larger objects by hanging the top mechanical linkage from the ceiling, thus providing an arbitrarily deep throat.
Scroll saws vary in price. The more costly saws are more accurate and easier to use, usually because they minimize vibration, though this is dependent in part upon design and frequency, with many models offering no vibrations in some frequencies, and increased vibration in others.
Uses
Scroll sawing is a popular hobby for many woodworkers. The tool allows a substantial amount of creativity and requires comparatively little space. In addition, many scroll saw projects require little more than the saw itself, reducing the investment in tools. A drill is required for interior cutouts, preferably a drill press for finely detailed work.
Scroll saws are often used to cut intricate curves and joints, a task they can complete quickly and with great accuracy. They can also be used to cut dovetail joints and are a common tool for thicker intarsia projects. When a fine blade is used, the kerf of a scroll saw is almost invisible.
Along with band saws, jigsaws, and now recently seen chainsaws, scroll saws are used with modern intarsia.
Scroll saws are comparatively safe. In particular, inadvertent contact between the blade and the operator's fingers or limbs is unlikely to result in serious injury, due to a smaller blade and relatively slower speed compared to tools such as a table saw.
Mode of operation
There are several types of scroll saws. The most common design is the parallel arm, in which a motor is attached near the back of the arms and the two arms always remain parallel to each other. The C-arm variant uses a solid "C" shaped arm, with the blade being mounted between the two ends of the "C". The parallel link type, used by Hawk, Excalibur, and DeWalt, has rods in the upper and lower arms that are "pushed" by the motor to move short (about 4 inches, or 100 millimetres) articulated arms which hold the blade.
The rigid arm scroll saw was popular until the 1970s but is no longer made. It has a single-piece cast iron frame. The blade is attached to a pitman arm on the bottom, which pulls the blade down. A spring in the upper arm pulls the blade back up again. This design has a significant weakness in that the tension on the blade changes with every stroke; modern scroll saws are all "constant tension" designs.
Blades
With the exception of blades made for very light duty saws, typical scroll saw blades are long. The major types are:
Skip tooth (or single skip tooth) which have a tooth, a gap, and then another tooth;
Double skip tooth (two teeth, a gap, then two teeth);
Crown or two-way, which have teeth facing both up and down so that the blade cuts on both the down-stroke (as with all other blades) and the up-stroke;
Spiral blades, which are essentially regular flat blades with a twist, so that teeth project on all sides;
Metal cutting blades made of hardened steel;
Diamond blades (wires coated with diamond fragments), for cutting glass.
Pin end blades are generally a bit thicker and are made to use on scroll saws that require pin end blades which are generally older, less expensive or made for entry level scrollers. Most newer higher-end scroll saws do not accept pin end blades.
Blades come in many weights, ranging from #10/0 (for making jewelry—about the size of a coarse hair) to #12, which is similar to a small band saw blade.
Another variation is called a reverse tooth blade. On reverse tooth blades, the bottom of the teeth are reversed (point up). This arrangement helps to reduce splintering on the bottom edges of the cut. However, it does not clear sawdust out of the cut as well as a regular blade, so cutting is slower and produces more heat. This heat reduces blade life and makes scorching of the workpiece more likely. Reverse tooth blades are especially useful when cutting softwood and plywood such as Baltic birch.
The latest variation is called "ultra-reverse". These blades are configured with 4–5 teeth down and then one up, repeated through the length of the blade. The blade clears dust very well and leaves a much cleaner back (very few "fuzzies"). These blades' sizes range from #1 through #9.
References
Further reading
Saws
Woodworking machines | wiki |
Multipla steht für:
Fiat Multipla, italienisches Automodell
Fiat 600 Multipla, siehe unter Fiat 600
Mehrfachstück eines Währungsnominals, siehe Multiplum | wiki |
The Parent Trap is een verfilming van het boek Das doppelte Lottchen van Erich Kästner. De film, waarin Hayley Mills, Maureen O'Hara en Brian Keith de hoofdrollen hebben, werd in 1961 uitgebracht.
Zie ook
The Parent Trap (1998) - herverfilming onder regie van Nancy Meyers.
Film uit 1961
Amerikaanse film | wiki |
TheatreWorks may refer to:
TheatreWorks (Silicon Valley), California
TheaterWorks (Hartford), Connecticut
TheatreWorksUSA
Theatre Works (Melbourne)
TheatreWorks (Singapore) | wiki |
Lemont – wieś w Stanach Zjednoczonych, w stanie Illinois, w hrabstwie Cook.
Wsie w stanie Illinois | wiki |
Group medical practices practice medicine by physicians who share resources.
There are approximately 230,187 physician practices in the United States. Among the physician practices, 16.5% had only one office-based physician in 2016. Physician group practices with 2-4 physicians make up 22.3% of physician offices in the United States, 19.8% have 5-10 physicians, 12.1% have 11-24 physicians, 6.3% have 25–49, and the remaining 13.5% have 50 or more physicians.
In recent years, many small or solo practitioners have come together to form larger specialty groups because of managed care.
Formal definition
The Centers for Medicare and Medicaid Services (CMS) changed the definition of "group practice" in its 2012 physician fee schedule to mean 25 or more eligible professionals in the same practice.
References
Medical lists | wiki |
Theban can refer to:
A thing or person of or from the city of Thebes, Greece.
A thing or person of or from the city of Thebes, Egypt.
The occult Theban alphabet | wiki |
The British twenty pound (£20) coin is a commemorative denomination of sterling coinage, first issued by the Royal Mint in 2013. It is minted in .999 fine silver. Twenty pound coins are legal tender but are intended as souvenirs and are almost never seen in general circulation.
Design
The designs which have appeared on the twenty pound coin's reverse are summarised in the table below.
Welsh Dragon £20
From 2016-2020 the royal mint has produced a Welsh Dragon £20 on a backdrop of the Visitor centre at the Royal mint experience. Some of these years have been accompanied by the same coin on a backdrop of the Welsh flag. The Visitor centre coin could only be purchased at the shop.
Legal tender status
The prolific issuance since 2013 of silver commemorative £20, £50 and £100 coins at face value has led to attempts to spend or deposit these coins,
prompting the Royal Mint to clarify the legal tender status of these silver coins.
Royal Mint guidelines advise that, although these coins were approved as legal tender, they are considered limited edition collectables not intended for general circulation.
References
External links
Royal Mint – £20 coin
Coins of the United Kingdom
Twenty-base-unit coins | wiki |
Tony Hawk: Shred est un jeu vidéo de simulation de skateboard, développé par Robomodo et édité par Activision en 2010 sur PlayStation 3, Xbox 360, Wii. C'est un spin-off de la série des Tony Hawk's.
Système de jeu
Développement
Réception
Références
Articles connexes
Skateboard
Trick
Jeu vidéo de skateboard
Jeu vidéo sorti en 2010
Jeu PlayStation 3
Jeu Xbox 360
Jeu Wii
Jeu vidéo développé aux États-Unis | wiki |
Canadian Mist is a brand of blended Canadian whisky produced by the Sazerac Company. It is distilled in Collingwood, Ontario, and is bottled at 40% alcohol by volume. It is triple-distilled using a continuous distillation process, and it is aged in charred white oak barrels in a temperature-controlled facility.
The brand was introduced in 1967 by Brown-Forman. The brand and distillery were sold to the Sazerac Company in 2020.
The product won a "double gold medal" award at the 2009 annual San Francisco World Spirits Competition. According to ratings aggregator Proof66, Canadian Mist is among the 10 Highest Rated Canadian Whiskies in the marketplace.
References
Canadian whisky
Brown–Forman brands
Products introduced in 1967
Sazerac Company brands | wiki |
The Bird may also refer to:
Finger (gesture), also called flipping the bird, to hold up the middle finger of the hand
The Bird, the official mascot of the Baltimore Orioles | wiki |
Amfenac, also known as 2-amino-3-benzoylbenzeneacetic acid, is a nonsteroidal anti-inflammatory drug (NSAID) with acetic acid moiety.
See also
Bromfenac (same structure as amfenac but with p-bromo)
References
Nonsteroidal anti-inflammatory drugs
2-Aminobenzophenones
Acetic acids | wiki |
Brain death is the permanent, irreversible, and complete loss of brain function which may include cessation of involuntary activity necessary to sustain life. It differs from persistent vegetative state, in which the person is alive and some autonomic functions remain. It is also distinct from comas as long as some brain and bodily activity and function remain, and it is also not the same as the condition locked-in syndrome. A differential diagnosis can medically distinguish these differing conditions.
Brain death is used as an indicator of legal death in many jurisdictions, but it is defined inconsistently and often confused by the public. Various parts of the brain may keep functioning when others do not anymore, and the term "brain death" has been used to refer to various combinations. For example, although one major medical dictionary considers "brain death" to be synonymous with "cerebral death" (death of the cerebrum), the US National Library of Medicine Medical Subject Headings (MeSH) system defines brain death as including the brainstem. The distinctions are medically significant because, for example, in someone with a dead cerebrum but a living brainstem, spontaneous breathing may continue unaided, whereas in whole-brain death (which includes brainstem death), only life support equipment would maintain ventilation. In certain countries, patients classified as brain-dead may legally have their organs surgically removed for organ donation.
Medicolegal history
Differences in operational definitions of death have obvious medicolegal implications (in medical jurisprudence and medical law). Traditionally, both the legal and medical communities determined death through the permanent end of certain bodily functions in clinical death, especially respiration and heartbeat. With the increasing ability of the medical community to resuscitate people with no respiration, heartbeat, or other external signs of life, the need for another definition of death occurred, raising questions of legal death. This gained greater urgency with the widespread use of life support equipment and the rising capabilities and demand for organ transplantation.
Since the 1960s, laws governing the determination of death have been implemented in all countries that have active organ transplantation programs. The first European country to adopt brain death as a legal definition (or indicator) of death was Finland in 1971, while in the United States, the state of Kansas had enacted a similar law earlier.
An ad hoc committee at Harvard Medical School published a pivotal 1968 report to define irreversible coma. The Harvard criteria gradually gained consensus toward what is now known as brain death. In the wake of the 1976 Karen Ann Quinlan case, state legislatures in the United States moved to accept brain death as an acceptable indication of death. In 1981, a presidential commission issued a landmark report entitled Defining Death: Medical, Legal, and Ethical Issues in the Determination of Death, which rejected the "higher-brain" approach to death in favor of a "whole-brain" definition. This report formed the basis for the Uniform Determination of Death Act, since enacted in 39 states. Today, both the legal and medical communities in the US use "brain death" as a legal definition of death, allowing a person to be declared legally dead even if life support equipment maintains the body's metabolic processes.
In the UK, the Royal College of Physicians reported in 1995, abandoning the 1979 claim that the tests published in 1976 sufficed for the diagnosis of brain death, and suggesting a new definition of death based on the irreversible loss of brain-stem function alone. This new definition, the irreversible loss of the capacity for consciousness and for spontaneous breathing, and the essentially unchanged 1976 tests held to establish that state, have been adopted as a basis of death certification for organ transplant purposes in subsequent Codes of Practice. The Australia and New Zealand Intensive Care Society (ANZICS) states that the "determination of brain death requires that there is unresponsive coma, the absence of brain-stem reflexes and the absence of respiratory centre function, in the clinical setting in which these findings are irreversible. In particular, there must be definite clinical or neuro-imaging evidence of acute brain pathology (e.g. traumatic brain injury, intracranial haemorrhage, hypoxic encephalopathy) consistent with the irreversible loss of neurological function." In Brazil, the Federal Council of Medicine revised its regulations in 2017, including "a requirement for the patient to meet specific physiological prerequisites and for the physician to provide optimized care to the patient before starting the procedures for diagnosing brain death and to perform complementary tests, as well as the need for specific training for physicians who make this diagnosis."
In 2020, an international panel of experts, the World Brain Death Project, published a guideline that:provides recommendations for the minimum clinical standards for determination of brain death/death by neurologic criteria (BD/DNC) in adults and children with clear guidance for various clinical circumstances. The recommendations have widespread international society endorsement and can serve to guide professional societies and countries in the revision or development of protocols and procedures for determination of brain death/death by neurologic criteria, leading to greater consistency within and between countries.
Medical criteria
Natural movements also known as the Lazarus sign or Lazarus reflex can occur on a brain-dead person whose organs have been kept functioning by life support. The living cells that can cause these movements are not living cells from the brain or brain stem; these cells come from the spinal cord. Sometimes these body movements can cause false hope for family members.
A brain-dead individual has no clinical evidence of brain function upon physical examination. This includes no response to pain and no cranial nerve reflexes. Reflexes include pupillary response (fixed pupils), oculocephalic reflex, corneal reflex, no response to the caloric reflex test, and no spontaneous respirations.
Brain death can sometimes be difficult to differentiate from other medical states such as barbiturate overdose, acute alcohol poisoning, sedative overdose, hypothermia, hypoglycemia, coma, and chronic vegetative states. Some comatose patients can recover to pre-coma or near pre-coma level of functioning, and some patients with severe irreversible neurological dysfunction will nonetheless retain some lower brain functions, such as spontaneous respiration, despite the losses of both cortex and brain stem functionality. Such is the case with anencephaly.
Brain electrical activity can stop completely, or drop to such a low level as to be undetectable with most equipment. An EEG will therefore be flat, though this is sometimes also observed during deep anesthesia or cardiac arrest. Although in the United States a flat EEG test is not required to certify death, it is considered to have confirmatory value. In the UK it is not considered to be of value because any continuing activity it might reveal in parts of the brain above the brain stem is held to be irrelevant to the diagnosis of death on the Code of Practice criteria.
The diagnosis of brain death is often required to be highly rigorous, in order to be certain that the condition is irreversible. Legal criteria vary, but in general require neurological examinations by two independent physicians. The exams must show complete and irreversible absence of brain function (brain stem function in UK), and may include two isoelectric (flat-line) EEGs 24 hours apart (less in other countries where it is accepted that if the cause of the dysfunction is a clear physical trauma there is no need to wait that long to establish irreversibility). The patient should have a normal temperature and be free of drugs that can suppress brain activity if the diagnosis is to be made on EEG criteria.
Also, a radionuclide cerebral blood flow scan that shows complete absence of intracranial blood flow must be considered with other exams – temporary swelling of the brain, particularly within the first 72 hours, can lead to a false positive test on a patient that may recover with more time.
CT angiography is neither required nor sufficient test to make the diagnosis.
Confirmatory testing is only needed under the age of 1. For children and adults, testing is optional. Other situations possibly requiring confirmatory testing include severe facial trauma where determination of brainstem reflexes will be difficult, pre-existing pupillary abnormalities, and patients with severe sleep apnea and/or pulmonary disease. Confirmatory tests include: cerebral angiography, electroencephalography, transcranial Doppler ultrasonography, and cerebral scintigraphy (technetium Tc 99m exametazime). Cerebral angiography is considered the most sensitive confirmatory test in the determination of brain death.
Organ donation
While the diagnosis of brain death has become accepted as a basis for the certification of death for legal purposes, it is a very different state from biological death – the state universally recognized and understood as death. The continuing function of vital organs in the bodies of those diagnosed brain dead, if mechanical ventilation and other life-support measures are continued, provides optimal opportunities for their transplantation.
When mechanical ventilation is used to support the body of a brain dead organ donor pending a transplant into an organ recipient, the donor's date of death is listed as the date that brain death was diagnosed.
In some countries (for instance, Spain, Finland, Wales, Portugal, and France), everyone is automatically an organ donor after diagnosis of death on legally accepted criteria, although some jurisdictions (such as Singapore, Spain, Wales, France, Czech Republic, Poland and Portugal) allow opting out of the system. Elsewhere, consent from family members or next-of-kin may be required for organ donation. In New Zealand, Australia, the United Kingdom (excluding Wales) and most states in the United States, drivers are asked upon application if they wish to be registered as an organ donor.
In the United States, if the patient is at or near death, the hospital must notify a designated Organ Procurement Organization (OPO) of the details, and maintain the patient while the patient is being evaluated for suitability as a donor. The OPO searches to see if the deceased is registered as a donor, which serves as legal consent; if the deceased has not registered or otherwise noted consent (e.g., on a driver's license), the OPO will ask the next of kin for authorization. The patient is kept on ventilator support until the organs have been surgically removed. If the patient has indicated in an advance health care directive that they do not wish to receive mechanical ventilation or has specified a do-not-resuscitate (DNR) order and the patient has also indicated that they wish to donate their organs, some vital organs such as the heart and lungs may not be able to be recovered.
Demographics
United States
Brain death is responsible for 2% of all adult and 5% of pediatric in-hospital deaths in the United States. In a nationwide survey of pediatric intensive care units (PICU) in the United States in 2019; there were more than 3,000 pediatric brain deaths out of a total of more than 15,344 children who died in PICUs. According to a national study, "brain death evaluations are performed infrequently, even in large PICUs."
See also
Brainstem death
Clinical death
Death
Persistent vegetative state
Information-theoretic death
Consciousness after death
Klaus Schäfer
References
External links
Medical aspects of death
Anatomical pathology
Brain | wiki |
Double-barrelled or double-barreled (with or without hyphens) may refer to:
Double-barrelled name, a type of surname
Double-barreled question, an improper formulation of a question
Double Barrelled Soul, 1967 album by Brother Jack McDuff and David Newman
Guns
Multiple-barrel firearm
Double-barreled cannon
Double-barreled shotgun
Double-Barreled Wheellock Pistol Made for Emperor Charles V
See also
Double Barrel (disambiguation) | wiki |
Ju-on – film del 2000
Ju-on – serie cinematografica | wiki |
Country captain is a curried chicken and rice dish, which is popular in the Southern United States. It was introduced to the United States through Charleston, Savannah, New York and Philadelphia, but has origins in the Indian subcontinent. The dish was also included in the U.S. military's Meal, Ready-to-Eat packs from 2000 to 2004, in honor of it being a favorite dish of George S. Patton.
It has also appeared on television shows in both the United States and in the United Kingdom, with chefs Bobby Flay, Atul Kochhar and Cyrus Todiwala all cooking the dish. Todiwala served his version to Queen Elizabeth II as part of her Diamond Jubilee celebrations, as well as Kevin Gillespie during Top Chef season 17.
Description
In its basic form, country captain is a mild stew made with browned chicken pieces, onions, and curry powder. Almonds and golden raisins or zante currants are usually added. Many versions also call for tomatoes, garlic, and bell peppers. The dish is served over white rice. With the exception of the rice, it is meant to be cooked all in the same pot. Chef Mamrej Khan has referred to the dish as one of the first fusion dishes to be developed, making it part of the Anglo-Indian cuisine.
Country captain originated in India as a simple spatchcock poultry or game recipe involving onions and curry and possibly enjoyed by British officers. One theory is that an early 19th-century British sea captain, possibly from the East India Company, working in the spice trade introduced it to the American South via the port of Savannah. The dish remains popular amongst the communities in Mumbai, India. The "country" part of the dish's name dates from when the term referred to things of Indian origin instead of British, and so the term "country captain" would have meant a captain of Indian origin, a trader along the coasts of India. Others claim that the word "captain" in the title is simply a corruption of the word "capon".
In 1991, The New York Times columnist Molly O'Neill researched the origin of the dish known as country captain, which had been a steady feature in southern cookbooks since the 1950s. Working with Cecily Brownstone, they discovered that the dish originally published in the United States in the pages of Miss Leslie’s New Cookery Book published in Philadelphia in 1857. The recipe required a "fine full-grown fowl". It also appeared in the kitchens of Alessandro Filippini, who was a chef with a restaurant on Wall Street in the 19th century.
Fans of the dish have included Franklin D. Roosevelt, who encountered country captain while visiting the Little White House in Warm Springs, Georgia. Roosevelt introduced it to George S. Patton, and it was Patton's love for the dish which subsequently resulted in it being added in his honor to the U.S. Army's Meal, Ready-to-Eat field rations in 2000. A variety of Southern chefs have recipes for the dish, including Paul Prudhomme, Paula Deen and Emeril Lagasse. The dish was featured on an episode of Throwdown! with Bobby Flay in season 6 guest-starring Matt and Ted Lee. It also appeared on the BBC One cooking show, Saturday Kitchen, with chef Atul Kochhar cooking the regular chicken and rice version of the dish.
Variations
Chef Cyrus Todiwala cooked a variation of country captain on Saturday Kitchen. His version was similar to shepherd's pie, in that the meat was baked under a layer of potato. He had previously cooked the dish for Queen Elizabeth II and the Duke of Edinburgh at Krishna Avanti Primary School in Harrow as part of the Queen's Diamond Jubilee celebrations in 2012. That version of the dish used a rare breed of lamb from the Orkney Islands which had been fed on seaweed. The dish is also now on the menu of Todiwala's London restaurant, Café Spice Namasté.
See also
Cuisine of the Southern United States
Indian cuisine
References
American stews
Anglo-Indian cuisine
Lowcountry cuisine
American chicken dishes
1857 introductions
Curry dishes | wiki |
Success Story may refer to:
Success Story (play), a stage play by playwright and screenwriter John Howard Lawson
"Success Story" (short story), a 1947 short story by P. G. Wodehouse, featuring the character Ukridge
"The Success Story" (Monkees Episode), the sixth episode of the first series of TV show The Monkees
"Success Story" (song), a song by The Who appearing on their album The Who By Numbers | wiki |
A state diagram is a type of diagram used in computer science and related fields to describe the behavior of systems. State diagrams require that the system described is composed of a finite number of states; sometimes, this is indeed the case, while at other times this is a reasonable abstraction. Many forms of state diagrams exist, which differ slightly and have different semantics.
Overview
State diagrams are used to give an abstract description of the behavior of a system. This behavior is analyzed and represented by a series of events that can occur in one or more possible states. Hereby "each diagram usually represents objects of a single class and track the different states of its objects through the system".
State diagrams can be used to graphically represent finite-state machines (also called finite automata). This was introduced by Claude Shannon and Warren Weaver in their 1949 book The Mathematical Theory of Communication. Another source is Taylor Booth in his 1967 book Sequential Machines and Automata Theory. Another possible representation is the state-transition table.
Directed graph
A classic form of state diagram for a finite automaton (FA) is a directed graph with the following elements (Q, Σ, Z, δ, q0, F):
Vertices Q: a finite set of states, normally represented by circles and labeled with unique designator symbols or words written inside them
Input symbols Σ: a finite collection of input symbols or designators
Output symbols Z: a finite collection of output symbols or designators
The output function ω represents the mapping of ordered pairs of input symbols and states onto output symbols, denoted mathematically as ω : Σ × Q→ Z.
Edges δ: represent transitions from one state to another as caused by the input (identified by their symbols drawn on the edges). An edge is usually drawn as an arrow directed from the present state to the next state. This mapping describes the state transition that is to occur on input of a particular symbol. This is written mathematically as δ : Q × Σ → Q, so δ (the transition function) in the definition of the FA is given by both the pair of vertices connected by an edge and the symbol on an edge in a diagram representing this FA. Item δ(q, a) = p in the definition of the FA means that from the state named q under input symbol a, the transition to the state p occurs in this machine. In the diagram representing this FA, this is represented by an edge labeled by a pointing from the vertex labeled by q to the vertex labeled by p.
Start state q0: (not shown in the examples below). The start state q0 ∈ Q is usually represented by an arrow with no origin pointing to the state. In older texts, the start state is not shown and must be inferred from the text.
Accepting state(s) F: If used, for example for accepting automata, F ∈ Q is the accepting state. It is usually drawn as a double circle. Sometimes the accept state(s) function as "Final" (halt, trapped) states.
For a deterministic finite automaton (DFA), nondeterministic finite automaton (NFA), generalized nondeterministic finite automaton (GNFA), or Moore machine, the input is denoted on each edge. For a Mealy machine, input and output are signified on each edge, separated with a slash "/": "1/0" denotes the state change upon encountering the symbol "1" causing the symbol "0" to be output. For a Moore machine the state's output is usually written inside the state's circle, also separated from the state's designator with a slash "/". There are also variants that combine these two notations.
For example, if a state has a number of outputs (e.g. "a= motor counter-clockwise=1, b= caution light inactive=0") the diagram should reflect this : e.g. "q5/1,0" designates state q5 with outputs a=1, b=0. This designator will be written inside the state's circle.
Example: DFA, NFA, GNFA, or Moore machine
S1 and S2 are states and S1 is an accepting state or a final state. Each edge is labeled with the input. This example shows an acceptor for binary numbers that contain an even number of zeros.
Example: Mealy machine
S0, S1, and S2 are states. Each edge is labeled with "j / k" where j is the input and k is the output.
Harel statechart
Harel statecharts, invented by computer scientist David Harel, are gaining widespread usage since a variant has become part of the Unified Modeling Language (UML). The diagram type allows the modeling of superstates, orthogonal regions, and activities as part of a state.
Classic state diagrams require the creation of distinct nodes for every valid combination of parameters that define the state. This can lead to a very large number of nodes and transitions between nodes for all but the simplest of systems (state and transition explosion). This complexity reduces the readability of the state diagram. With Harel statecharts it is possible to model multiple cross-functional state diagrams within the statechart. Each of these cross-functional state machines can transition internally without affecting the other state machines in the statechart. The current state of each cross-functional state machine in the statechart defines the state of the system. The Harel statechart is equivalent to a state diagram but it improves the readability of the resulting diagram.
Alternative semantics
There are other sets of semantics available to represent state diagrams. For example, there are tools for modeling and designing logic for embedded controllers. These diagrams, like Harel's original state machines, support hierarchically nested states, orthogonal regions, state actions, and transition actions.
State diagrams versus flowcharts
Newcomers to the state machine formalism often confuse state diagrams with flowcharts. The figure below shows a comparison of a state diagram with a flowchart. A state machine (panel (a)) performs actions in response to explicit events. In contrast, the flowchart (panel (b)) does not need explicit events but rather transitions from node to node in its graph automatically upon completion of activities.
Nodes of flowcharts are edges in the induced graph of states.
The reason is that each node in a flowchart represents a program command.
A program command is an action to be executed.
So it is not a state, but when applied to the program's state, it results in a transition to another state.
In more detail, the source code listing represents a program graph.
Executing the program graph (parsing and interpreting) results in a state graph.
So each program graph induces a state graph.
Conversion of the program graph to its associated state graph is called "unfolding" of the program graph.
The program graph is a sequence of commands.
If no variables exist, then the state consists only of the program counter, which keeps track of where in the program we are during execution (what is the next command to be applied).
In this case before executing a command the program counter is at some position (state before the command is executed).
Executing the command moves the program counter to the next command.
Since the program counter is the whole state, it follows that executing the command changed the state.
So the command itself corresponds to a transition between the two states.
Now consider the full case, when variables exist and are affected by the program commands being executed.
Then between different program counter locations, not only does the program counter change, but variables might also change values, due to the commands executed.
Consequently, even if we revisit some program command (e.g. in a loop), this doesn't imply the program is in the same state.
In the previous case, the program would be in the same state, because the whole state is just the program counter, so if the program counterpoints to the same position (next command) it suffices to specify that we are in the same state.
However, if the state includes variables, then if those change value, we can be at the same program location with different variable values, meaning in a different state in the program's state space.
The term "unfolding" originates from this multiplication of locations when producing the state graph from the program graph.
A self transition is a transition where the initial and the final state are the same.
A representative example is a do loop incrementing some counter until it overflows and becomes 0 again.
Although the do loop executes the same increment command iteratively, so the program graph executes a cycle, in its state space is not a cycle, but a line.
This results from the state being the program location (here cycling) combined with the counter value, which is strictly increasing (until the overflow), so different states are visited in sequence, until the overflow.
After the overflow the counter becomes 0 again, so the initial state is revisited in the state space, closing a cycle in the state space (assuming the counter was initialized to 0).
The figure above attempts to show that reversal of roles by aligning the arcs of the state diagrams with the processing stages of the flowchart.
You can compare a flowchart to an assembly line in manufacturing because the flowchart describes the progression of some task from beginning to end (e.g., transforming source code input into object code output by a compiler). A state machine generally has no notion of such a progression. The door state machine shown at the top of this article, for example, is not in a more advanced stage when it is in the "closed" state, compared to being in the "opened" state; it simply reacts differently to the open/close events. A state in a state machine is an efficient way of specifying a particular behavior, rather than a stage of processing.
Other extensions
An interesting extension is to allow arcs to flow from any number of states to any number of states. This only makes sense if the system is allowed to be in multiple states at once, which implies that an individual state only describes a condition or other partial aspect of the overall, global state. The resulting formalism is known as a Petri net.
Another extension allows the integration of flowcharts within Harel statecharts. This extension supports the development of software that is both event driven and workflow driven.
See also
David Harel
DRAKON
SCXML an XML language that provides a generic state-machine based execution environment based on Harel statecharts.
UML state machine
YAKINDU Statechart Tools is a software for modeling state diagrams (Harel statecharts, Mealy machines, Moore machines), simulation, and source code generation.
References
External links
Introduction to UML 2 State Machine Diagrams by Scott W. Ambler
UML 2 State Machine Diagram Guidelines by Scott W. Ambler
Intelliwizard - UML StateWizard - A discontinued round-trip UML dynamic modeling/development framework and tool that ran in popular IDEs under an open-source license.
YAKINDU Statechart Tools - an Open-Source-Tool for the specification and development of reactive, event-driven systems with the help of state machines.
Understanding and Using State Machines MATLAB Tech Talks on State Machines
FSM: Open Source Finite State Machine Generation in Java by Alexander Sakharov FSM
scxmlcc An efficient scxml state machine to C++ compiler.
SMC: An Open Source State Machine Compiler that generates FSM for many languages as C, Python, Lua, Scala, PHP, Java, VB, etc. SMC
Models of computation
Unified Modeling Language diagrams
Diagrams
Infographics
Application-specific graphs
Graph drawing
Modeling languages | wiki |
Governor Bentinck may refer to:
William Bentinck (Royal Navy officer) (1764–1813), Governor of St. Vincent and the Grenadines from 1798 to 1802
Lord William Bentinck (1774–1839), Governor-General of India from 1828 to 1835 | wiki |
A. lepidus may refer to:
Acusilas lepidus, an orb-weaver spider species found in Myanmar
Argyrodes lepidus, a tangle web spider species
See also
Lepidus (disambiguation) | wiki |
Кропив'янка (Sylvia) — рід птахів ряду горобцеподібних
Кропив'янка, або уртикарія — хвороба людини
Кропив'янка — річка у Вінницькій області, притока Південного Бугу | wiki |
Mair Jones is a former Welsh international lawn and indoor bowler.
In 1985 Jones won a triples bronze medal at the 1985 World Outdoor Bowls Championship in Preston, Victoria, Melbourne, Australia with Rita Jones and Linda Parker.
Jones played for the Welsh International team for 17 years and was a National Champion in 1962.
References
Living people
Welsh female bowls players
Year of birth missing (living people) | wiki |
A wingman is a pilot who supports another in a potentially dangerous flying environment.
Wingman also may refer to:
Television
"Wingman" (Person of Interest), an episode of the television series Person of Interest
"Wingman" (Lucifer), an episode of the television series Lucifer
"Wingman" (Sanctuary), an episode of the television series Sanctuary
"Wingman" (Kim's Convenience), an episode of the television series Kim's Convenience
"The Wingman", an episode of the television series Schitt's Creek
Other uses
Wing-Man, a manga series
Wingmen (novel), a novel by Ensan Case
Wingman (social), a companion intended to facilitate social interaction
Wingman and Wingman 2, Enix home computer games
Ko Wing-man (born 1957), Hong Kong physician and politician
See also
Winger (disambiguation) | wiki |
Camlin may refer to:
Camlin Hotel, in Seattle, Washington
River Camlin, Irish river
Camlin, County Antrim, a townland and civil parish in County Antrim, Northern Ireland
Kokuyo Camlin, an Indian stationery company | wiki |
M. lepidus may refer to:
Misumenops lepidus, a spider species in the genus Misumenops
Mycetoporus lepidus, a beetle species in the genus Mycetoporus
See also
Lepidus (disambiguation) | wiki |
P. lepidus may refer to:
Philanthus lepidus, a wasp species in the genus Philanthus
Pisenor lepidus, a spider species in the genus Pisenor
Poecilus lepidus, a beetle species in the genus Poecilus
Proprioseiopsis lepidus, a mite species in the genus Proprioseiopsis
See also
Lepidus (disambiguation) | wiki |
In differential geometry, the spherical image of a unit-speed curve is given by taking the curve's tangent vectors as points, all of which must lie on the unit sphere. The movement of the spherical image describes the changes in the original curve's direction If is a unit-speed curve, that is , and is the unit tangent vector field along , then the curve is the spherical image of . All points of must lie on the unit sphere because .
References
Differential geometry | wiki |
Mixed spice, also called pudding spice, is a British blend of sweet spices, similar to the pumpkin pie spice used in the United States. Cinnamon is the dominant flavour, with nutmeg and allspice. It is often used in baking, or to complement fruits or other sweet foods.
The term "mixed spice" has been used for this blend of spices in cookbooks at least as far back as 1828 and probably much earlier.
Mixed spice is very similar to a Dutch spice mix called or speculaaskruiden, which are used for example to spice food associated with the Dutch Sinterklaas celebration at December 5. It is generally used for sweet pastries eaten during the cold season, such as speculaas (a kind of shortbread) and appeltaart (apple pastry). Koekkruiden can contain cardamom, in addition to cinnamon, cloves and allspice, and sometimes also nutmeg. The tradition of pastries and dishes containing mixed spices together with the frequent use of chocolate during traditional festivities has its roots in the Dutch colonial past.
Ingredients
Mixed spice typically contains:
Cinnamon (or cassia)
Nutmeg
Allspice
It may also contain, or commonly have added to it:
Cloves
Ginger
Coriander (seed)
Caraway
Cayenne pepper (historically)
See also
Spice mix
Pumpkin pie spice
References
Herb and spice mixtures
Sinterklaas food | wiki |
Smile (March 26, 1982 – June 1997) was a Florida-bred racehorse born in 1982. He was sired by the stallion In Reality and was out of the Boldnesian mare Sunny Smile, who also produced the Gr. 2 winner Sunshine Today and the multiple stakes winner Charging Through.
Race career
Smile started his race career at Calder Race Track in Florida, where he was bred. He was undefeated throughout his two-year-old campaign with wins in the Criterium, Dr. Fager, Affirmed and In Reality Stakes. In his three-year-old season, Smile won in the Carry Back Stakes before moving on to Arlington Park. He placed in the Gr. 2 Sheridan Stakes and came in second to Banner Bob, then won the then-Gr. 1 Arlington Classic. In the Gr. 1 American Derby, Smile came in third behind that year’s Belmont Stakes winner, Creme Fraiche. Smile then won the Grade III Fairmount Park Derby, setting a new track record for 9 furlongs with a time of 1:49.0. After two more races, he went to Aqueduct to take part in that year’s Breeders' Cup Sprint. Smile came in second to champion Precisionist. In his last start at age 3, he competed in the Gr. 1 Vosburgh Stakes and came in fourth behind Another Reef and Pancho Villa.
Smile’s four-year-old season got off to a rocky start with a seventh-place finish in the Metropolitan Handicap and a fourth in the True North Handicap. His season then improved with a win in the Canterbury Cup and a showing in the Gr. 3 Cornhusker Handicap. Smile got one more win in the Gr. 3 Equipoise Mile and a sixth place in the Philadelphia Park Breeders’ Cup before he took another try at the Breeders' Cup Sprint. Smile won the race, equaling the stakes record set the previous year by Precisionist. Smile was named that year’s Eclipse Champion Sprinter. In 1987, he started his five-year-old season with a second in the Tropical Park Breeders’ Cup. He finished in the money in one of his next two starts. Smile’s trainer decided "...his last few races were not up to his standard and he has earned his retirement." A week after his fourth-place finish in the Gulfstream Park Breeders’ Cup, he was shipped back to his place of birth, Tartan Farms, to take over at stud for his sire, In Reality, who was getting on in years.
Breeding career
In Reality was known for being a sire of sires, so expectations were high for Smile. He first stood stud at Tartan Farms for a fee of US$15,000. While he produced stakes winners in the colt Smiling Time and the filly Lavender, he was not a major success and was eventually relocated to a more modest farm in Texas. In 2003, a promising two-year-old named Smarty Jones (son of Smile's daughter I'll Get Along) won the Kentucky Derby and Preakness Stakes in 2004. Smile died in Texas at the age of 15 from complications of the neurological disease EPM.
References
1982 racehorse births
1997 racehorse deaths
Racehorses bred in Florida
Racehorses trained in the United States
Horse racing track record setters
Breeders' Cup Sprint winners
Eclipse Award winners
Thoroughbred family 8-a
Godolphin Arabian sire line | wiki |
The Flintstone Funnies is an American animated package show produced by Hanna-Barbera that aired on NBC from September 18, 1982 to September 8, 1984. This is the final incarnation of The Flintstones that premiered on NBC.
The series consisted of repackaged reruns of the six segments from The Flintstone Comedy Show (two and/or three segments aired per half-hour episode). The segments included The Flintstone Family Adventures, Bedrock Cops, Pebbles, Dino and Bamm-Bamm, Captain Caveman, Dino and Cavemouse and The Frankenstones.
Episodes
For episode titles and synopsis, see The Flintstone Comedy Show
Voice cast
Gay Autterson as Betty Rubble, Wiggy Rockstone
Mel Blanc as Barney Rubble, Captain Caveman, Dino
Henry Corden as Fred Flintstone
Ruta Lee as Hidea Frankenstone
Kenneth Mars as Lou Granite
Mitzi McCall as Penny Pillar
Don Messick as Schleprock
Charles Nelson Reilly as Frank Frankenstone
Paul Reubens as Freaky Frankenstone
Zelda Rubinstein as Atrocia Frankenstone
Michael Sheehan as Bamm-Bamm Rubble
John Stephenson as Mr. Slate
Russi Taylor as Pebbles Flintstone, Cavemouse
Jean Vander Pyl as Wilma Flintstone
Lennie Weinrib as Moonrock Crater, Sgt. Boulder
Frank Welker as Shmoo, Rockjaw
References
External links
The Flintstone Funnies at the Big Cartoon DataBase
The Flintstones spin-offs
1982 American television series debuts
1984 American television series endings
1980s American animated television series
American animated television spin-offs
American children's animated comedy television series
Crossover animated television series
Li'l Abner
NBC original programming
Television series by Hanna-Barbera
Television series set in prehistory
Television series about cavemen | wiki |
Opblaasboot (rigid-inflatable boat)
Raadsinformatiebrief | wiki |
Sound As Ever may refer to:
Sound As Ever (You Am I album), 1993
Sound As Ever (The Burritos album), 2011 | wiki |
Phosphorus nitride refers to several chemical compounds of phosphorus and nitrogen:
Phosphorus mononitride
Tetraphosphorus hexanitride
Triphosphorus pentanitride | wiki |
Phosphorus mononitride is an inorganic compound with the chemical formula PN. Containing only phosphorus and nitrogen, this material is classified as a binary nitride.
It is the first identified phosphorus compound in the interstellar medium.
It is an important molecule in interstellar medium and the atmospheres of Jupiter and Saturn.
See also
Triphosphorus pentanitride
References
Nitrides
Phosphorus compounds
Solids | wiki |
Certified Public Accountant (CPA) is the title of qualified accountants in numerous countries in the English-speaking world. It is generally equivalent to the title of chartered accountant in other English-speaking countries. In the United States, the CPA is a license to provide accounting services to the public. It is awarded by each of the 50 states for practice in that state. Additionally, all states except Hawaii have passed mobility laws to allow CPAs from other states to practice in their state. State licensing requirements vary, but the minimum standard requirements include passing the Uniform Certified Public Accountant Examination, 150 semester units of college education, and one year of accounting-related experience.
Continuing professional education (CPE) is also required to maintain licensure. Individuals who have been awarded the CPA but have lapsed in the fulfillment of the required CPE or who have requested conversion to inactive status are in many states permitted to use the designation "CPA Inactive" or an equivalent phrase. In most U.S. states, only CPAs are legally able to provide attestation (including auditing) opinions on financial statements. Many CPAs are members of the American Institute of Certified Public Accountants and their state CPA society.
State laws vary widely regarding whether a non-CPA is even allowed to use the title "accountant". For example, Texas prohibits the use of the designations "accountant" and "auditor" by a person not certified as a Texas CPA, unless that person is a CPA in another state, is a non-resident of Texas, and otherwise meets the requirements for practice in Texas by out-of-state CPA firms and practitioners.
CPA in other countries
In the United States, "CPA" is an initialism for Certified Public Accountant which is a designation given by a state governing agency, whereas other countries around the world have their own designations, which may be equivalent to "CPA".
In the United Kingdom, "CPA" is an initialism for Certified Public Accountant as well, but refers to an accounting and finance professional who is a member of the Certified Public Accountants Association (formerly the Association of Certified Public Accountants).
In Australia, the term "CPA" is an initialism for Certified Practicing Accountant. To become a CPA in Australia, it also requires a certain amount of education and experience to be eligible working in some specific areas in the accounting field.
In Canada, "CPA" is an initialism for Chartered Professional Accountant. This designation is for someone who would like to be a Canadian CPA. In order to be qualified for this certificate, candidates who major in accounting will get accepted to enter CPA Professional Education Program (CPA PEP). Provinces in Canada also allow non-accounting majors and international candidates to meet the requirements if they get into the CPA Prerequisite Education Program (CPA PREP).
History of profession
In 1660, the first person who would conduct an audit was chosen in order to be able to manage the money that was raised by England in Virginia, United States. With the help of chartered accountants from England and Scotland for training Americans to learn the procedures of accounting, many firms were established in America. The first American one was in 1895.
On July 28, 1882, the Institute of Accountants and Bookkeepers of the City of New York became the first accounting corporation which supports the need of people in the accounting field and for educational purposes. With the accountancy and industry growing in the world, the need of looking for services from professional accountants who had higher standards and were recognized had been considered. In 1887, the American Association of Public Accountants was created to set moral standards for the practice of accounting.
On April 17, 1896, Chapter 312 of the Laws of the State of New York established that the Regents of the University of the State of New York would provide a Certificate of Public Accountancy to individuals over age 21, of good moral character, and who possessed or intended to declare citizenship in the United States with appropriate accounting education or experience either through examination or previous experience. This was the first time the title "Certified Public Accountant" was regulated. Examinations were held in both Buffalo and New York City. Frank Broaker was licensee #1 and he received his certificate solely through previous experience as a public accountant and did not take an examination, commonly referred to as grandfathering. Broaker died on November 12, 1941. The first person to receive the CPA through examination and previous experience was Joseph Hardcastle, who would go on to become an accounting theorist and New York University professor. Hardcastle died on June 16, 1906, after being thrown from a horse after an accident with a wagon. The Chapter was introduced by New York Senator Albert Wray, New York Assemblyman Henry Marshall, and signed by New York Governor Morton as part of business reform. The Regents appointed a Board of Examiners, similar to today's NASBA, the first members of which were Charles Sprague, Frank Broaker, and C. W. Haskins
Many accounting professionals believed the 150 credit requirement—implemented in several states first in 1988 and then expanded to nearly all states in 2001—would lead to more knowledgeable, experienced CPAs. The National Association of State Board of Accountancy (NASBA) collected and analyzed data from 1996 to 1998 to verify the effectiveness of the measure. Researchers studied more than 116,000 candidates who took the exam between 1996 and 1998. 33% of respondents had more than 150 college credit hours, while 67% had less than 150 credit hours. The research reveals that for candidates with less than 150 credits, only 13% passed the CPA exam on their first try. Conversely, for candidates with 150 or more credits, 21% passed the CPA exam on their first try. Some suggest extraneous variables—including the additional study time those possessing 150 credits likely have while still enrolled in university—could distort the verifiability of the study.
Services provided
One important function performed by CPAs relates to assurance services. The most commonly performed assurance services are financial audit services where CPAs attest to the reasonableness of disclosures, the freedom from material misstatement, and the adherence to the applicable generally accepted accounting principles (GAAP) in financial statements. CPAs can also be employed within corporations (termed "the private sector" or "industry") in finance or operations positions such as financial analyst, finance manager, controller, chief financial officer (CFO), or chief executive officer (CEO). These CPAs do not provide services directly to the public.
Although some CPA firms serve as business consultants, the consulting role has been under scrutiny following the Enron scandal where Arthur Andersen simultaneously provided audit and consulting services which affected its ability to maintain independence in its audit duties. This incident resulted in many accounting firms divesting their consulting divisions, but this trend has since reversed. In audit engagements, CPAs are (and have always been) required by professional standards and Federal and State laws to maintain independence (both in fact and in appearance) from the entity for which they are conducting an attestation (audit and review) engagement. Although most individual CPAs who work as consultants do not also work as auditors, if the CPA firm is auditing the same company that the firm also does consulting work for, then there is a conflict of interest. This conflict voids the CPA firm's independence for multiple reasons, including: (1) the CPA firm would be auditing its own work or the work the firm suggested, and (2) the CPA firm may be pressured into unduly giving a positive (unmodified) audit opinion so as not to jeopardize the consulting revenue the firm receives from the client.
CPAs also have a niche within the income tax return preparation industry. Many small to mid-sized firms have both a tax and an auditing department. Along with attorneys and Enrolled Agents, CPAs may represent taxpayers in matters before the Internal Revenue Service (IRS). Although the IRS regulates the practice of tax representation, it has no authority to regulate tax return preparers.
Some states also allow unlicensed accountants to work as public accountants. For example, California allows unlicensed accountants to work as public accountants if they work under the control and supervision of a CPA. However, the California Board of Accountancy itself has determined that the terms "accountant" and "accounting" are misleading to members of the public, many of whom believe that a person who uses these terms must be licensed. As part of the California Poll, survey research showed that 55 percent of Californians believe that a person who advertises as an "accountant" must be licensed, 26 percent did not believe a license was required, and 19 percent did not know.
Whether providing services directly to the public or employed by corporations or associations, CPAs can operate in virtually any area of finance including:
Assurance and attestation services
Corporate finance (merger and acquisition, initial public offerings, share and debt issuings)
Corporate governance
Estate planning
Financial accounting
Governmental accounting
Financial analysis
Financial planning
Forensic accounting (preventing, detecting, and investigating financial frauds)
Income tax
Information technology, especially as applied to accounting and auditing
Management consulting and performance management
Tax preparation and planning
Venture capital
Financial reporting
Regulatory compliance
CPA exam
To become a CPA in the United States, the candidate must sit for and pass the Uniform Certified Public Accountant Examination (Uniform CPA Exam), which is set by the American Institute of Certified Public Accountants (AICPA) and administered by the National Association of State Boards of Accountancy (NASBA). The Uniform CPA Exam consists of the following sections: Auditing and Attestation (AUD), Financial Accounting and Reporting (FAR), Regulation (REG), and Business Environment Concepts (BEC). The CPA designation was first established in law in New York State on April 17, 1896.
Before 1917, individual states had their own licensing examinations where accountants could earn the CPA credential, but this differed significantly from state to state. The exams were administered to further the cause of professional cohesion among the accounting profession, verified membership to practice accounting, and for individuals to earn membership in the Institute of Public Accountants (IPA). In response to these factors, the first uniform exam was held on June 14–15, 1917. It established four sections: Auditing, Commercial Law, Accounting Theory and Practice Part 1, and Accounting Theory and Practice Part 2. The Commercial Law and Accounting Theory and Practices sections were precursors to the REG (Business Law and Tax) and FAR (Financial Accounting) sections. The Auditing, Business Law, and Accounting Theory exam segments were each 3.5 hours in length and totaled 10.5 hours. The Accounting Practice Parts I and II were both 4.5 hours in length, totaling to 9 hours. All states would start using the standard CPA exam administered by the organization which would eventually become the AICPA by 1952. The use of calculators was forbidden on the exam until 1994.
Prior to 2004, individuals had to take all four sections of the CPA exam in the span of two days. In 2004, upon recommendation by the AICPA, there was a shift to take the four sections at different dates. Also in 2004, the CPA exam moved from paper and pencil to an online format. The shift to online allowed the exam to test application and technological skills through task-based simulations. It also led to an increased emphasis on information technology with regards to risk assessment for internal controls.
While not as significant as the changes to come in 2024, the CPA exam saw some changes in 2017. The biggest change in 2017 was the amount of knowledge required to answer each of the questions. Before 2017, questions on the CPA exam tested the applicants’ remembering and understanding of the concept. Remembering and understanding corresponds to the lowest levels of Bloom’s Taxonomy. Starting in 2017, examiners wanted to include questions that tested higher levels of Bloom’s Taxonomy. As such, the number of questions testing remembering and understanding was reduced and questions that tested an applicant’s analysis and application of a skill were added to the CPA exam. Examiners saw that employers of new CPAs would require the use of analysis and application of skills instead of basic remembering and understanding.
Specifically, the Regulation (REG) section of the CPA exam saw changes in 2017. While the REG section of the CPA exam does not test the highest levels of Bloom’s taxonomy, 60–80 percent of the questions on the exam test analysis and application skills. Only 25–35 percent of questions test remembering and understanding following the changes to the exam. Prior to the changes, a majority of questions were remembering and understanding. The Auditing and Attestation (AUD) section will test the highest levels of Bloom’s Taxonomy in the form of evaluation questions. In addition, the REG exam allotted more time in the newer version to four hours versus three hours for the older exam. The 2017 version now contains 76 multiple choice questions and either eight or nine task-based simulations to further application based learning.
In 2019, the AICPA conducted a study that showed that CPAs needed an increased skill set in data analytics, excel, and overall, more technological skills. While the CPA exam tested knowledge on information technology, employers believed that not enough was being tested. This led to the evolution of the 2024 exam, known as the Core+Discipline Model. Starting in 2024, all CPA candidates will take the same three core sections of Accounting, Auditing, and Taxation. Then each candidate will have a choice between Taxation Compliance and Planning, Business Reporting and Analysis, and Information Systems Control. The new model will allow candidates to show a deeper knowledge of the content while still testing the foundation of accounting principles. It will also allow candidates to demonstrate a knowledge of technology, critical thinking skills, advanced problem-solving skills, and sound professional judgment which is an important skill used in the workplace and profession.
Eligibility to sit for the Uniform CPA Exam is determined by individual state boards of accountancy. Many states have adopted what is known as the "150 hour rule" (150 college semester units or the equivalent), which usually requires an additional year of education past a regular 4-year college degree, or a master's degree. Some universities offer a 5-year combined bachelor's/master's degree program, allowing a student to earn both degrees while receiving the 150 hours needed for exam eligibility.
The Uniform CPA Exam tests general principles of state law such as the laws of contracts and agency (questions not tailored to the variances of any particular state) and some federal laws as well.
Other licensing and certification requirements
Although the CPA exam is uniform, licensing and certification requirements are imposed separately by each state's laws and therefore vary from state to state.
State requirements for the CPA qualification can be summed up as the Three Es—education, examination and experience. The education requirement normally must be fulfilled as part of the eligibility criteria to sit for the Uniform CPA Exam. The examination component is the Uniform CPA Exam itself. Some states have a two-tier system whereby an individual would first become certified—usually by passing the Uniform CPA Exam. That individual would then later be eligible to be licensed once a certain amount of work experience is accomplished. Other states have a one-tier system whereby an individual would be certified and licensed at the same time when both the CPA exam is passed and the work experience requirement has been met.
Two-tier states include Alabama, Florida, Illinois, Montana, and Nebraska. The trend is for two-tier states to gradually move towards a one-tier system. Since 2002, the state boards of accountancy in Washington and South Dakota have ceased issuing CPA "certificates" and instead issue CPA "licenses". Illinois planned to follow suit in 2012.
A number of states are two-tiered, but require work experience for the CPA certificate, such as Ohio and Pennsylvania.
Work experience requirement
The experience component varies from state to state:
The two-tier states generally do not require that the individual have work experience to receive a CPA certificate. Work experience is required, however, to receive a license to practice.
Some states, such as Massachusetts, waive the work experience requirement for those with a higher academic qualification compared to the state's requirement to appear for the Uniform CPA.
The majority of states still require work experience to be of a public accounting nature, namely two years audit or tax experience, or a combination of both. An increasing number of states, however, including Oregon, Virginia, Georgia and Kentucky, accept experience of a more general nature in the accounting area. In Texas, only one year of experience in accounting under the supervision of a CPA is required; such experience does not have to be in public accounting. This allows persons to obtain the CPA designation while working for a corporation's finance function.
The majority of states require an applicant's work experience to be verified by someone who is already licensed as a CPA. This requirement can cause difficulties for applicants based outside the United States. However, some states such as Colorado and Oregon also accept work experience certified by a Chartered Accountant.
Ethics
Over 40 of the state boards now require applicants for CPA status to complete a special examination on ethics, which is effectively a fifth exam in terms of requirements to become a CPA. The majority of these accept the AICPA self-study Professional Ethics for CPAs CPE course or another course in general professional ethics. Many states, however, require that the ethics course include a review of that state's specific rules for professional practice.
Continuing professional education
Like other professionals, CPAs are required to take continuing education courses toward continuing professional development (continuing professional education [CPE]) to renew their license. Requirements vary by state (Wisconsin does not require any CPE for CPAs) but the vast majority require an average of 40 hours of CPE every year with a minimum of 20 hours per calendar year. The requirement can be fulfilled through attending live seminars, webcast seminars, or through self-study (textbooks, videos, online courses, all of which require a test to receive credit). In general, state boards accept group live and group internet-based credits for all credit requirements, while some states cap the number of credits obtained through the self-study format. All CPAs are encouraged to periodically review their state requirements. As part of the CPE requirement, most states require their CPAs to take an ethics course at some frequency (such as every or every other renewal period). Ethics requirements vary by state and the courses range from 2–8 hours. AICPA guidelines (which are adopted by many state boards) grant licensees 1 hour of CPE credit for every 50 minutes of instruction.
Loss of licensure
A CPA license may be suspended or revoked for various reasons. Common reasons include these:
Allowing the license to lapse without renewing in a timely manner.
Performing attestation services under an unlicensed/unregistered CPA firm or under a CPA firm permit which has expired.
Continuing to hold out as an active CPA on an expired license, which includes continued use of the CPA title on business cards, letterhead, office signage, correspondence, etc. after the license has expired.
Using fraud or deceit in obtaining or renewing the CPA license, the most common occurrence being misrepresenting or falsifying compliance with or completion of the continuing education requirements as a condition for renewal.
Being suspended or barred from practicing before another regulatory body such as the SEC or the IRS.
"Discreditable acts", which can include
failure to follow applicable standards (such as auditing standards when examining financial statements, or tax code when preparing tax returns); or
violation of felony or serious misdemeanor criminal laws, which may or not be related to the practice of accountancy. (A notable example of a CPA whose license was revoked for non-financial related criminal activity is John Battaglia, convicted of the capital murders of his children).
Impact of technology
Many tasks that a CPA used to do while working have now been automated. Therefore current and future CPAs are required to do more complex tasks with technology as the simpler tasks have become automated. An example of a more complex task would include analyzing and interpreting data using a visualization software. Technology is used regularly in the job to the point where technological proficiency is needed when starting as a CPA.
Since technological proficiency is more important than in prior years, accounting organizations have begun starting to teach technology within the accounting curricula in colleges and universities. One big change was in 2013, when the Association to Advance Collegiate Schools of Business (AACSB) mandated that information technology be included in all accredited accounting programs. The transition to add information technology has not been one without challenges. One specific challenge with regards to adding information technology into accounting curricula is the balance of preparing students for the CPA exam and preparing to work as a CPA following graduation. Preparing for the CPA exam and preparing to work as a CPA after graduation can be different, making this difficult for professors and schools to figure out what to include in their curricula. Instructors generally agree that including data analytics should be included when teaching about accounting information systems as a whole but few instructors think that data analytics should be in the entire accounting curricula at schools.
Demographics of CPAs
A disparity exists among the demographics of AICPA members, specifically as it relates to class and gender. Between 1976 and 2005, 77% of CPAs were either middle or upper class and nearly half of all CPA candidates belonged to an upper middle class socioeconomic background. Although AICPA membership is predominated by individuals from wealthier socioeconomic backgrounds, 20% of AICPA members were lower class between 1976 and 2005. This indicates that the CPA profession is not exclusionary, but rather that it provides upward social and economic mobility. While women only accounted for 2.4% of all CPAs between 1934 and 1975, 50-60% of all hiring's by CPA firms were women between 2001 and 2010. Considering the unique barriers female CPAs may experience within the accounting profession, it is theorized that female CPAs come from higher socioeconomic backgrounds to overcome any gender bias they may experience. This would elucidate the higher prevalence of wealthy AICPA members who are women. These findings indicate that the demographic discrepancies among AICPA members have narrowed significantly in recent years.
Practice mobility: the substantial equivalency rule
An accountant is required to meet the legal requirements of any state in which the accountant wishes to practice.
In recent years, practice mobility for CPAs has become a major business concern for CPAs and their clients. Practice mobility for CPAs is the general ability of a licensee in good standing from a substantially equivalent state to gain practice privilege outside of the practitioner's home state without getting an additional license in the state where the CPA will serve a client or an employer. In today's digital age, many organizations require the professional services of CPAs to conduct business on an interstate and international basis and have compliance responsibilities in multiple jurisdictions. As a result, the practice of CPAs often extends across state lines and international boundaries.
Differing requirements for CPA certification, reciprocity, temporary practice and other aspects of state accountancy legislation in the 55 U.S. licensing jurisdictions (the 50 states, Puerto Rico, the District of Columbia, the U.S. Virgin Islands, Guam and the Commonwealth of the Northern Mariana Islands) make the interstate practice and mobility of CPAs more complicated. By removing boundaries to practice in the U.S., CPAs are able to more readily serve individuals and businesses in need of their expertise. At the same time, the state board of accountancy's ability to discipline is enhanced by being based on a CPA and the CPA firm's performance of services (either physically, electronically or otherwise within a state), rather than being based on whether a state license is held.
The American Institute of Certified Public Accountants (AICPA) and the National Association of State Boards of Accountancy (NASBA) have analyzed the current system for gaining practice privileges across state lines and have endorsed a uniform mobility system. This model approach is detailed through the substantial equivalency provision (Section 23) of the Uniform Accountancy Act (UAA). The UAA is an "evergreen" model licensing law co-developed, maintained, reviewed and updated by the AICPA and NASBA. The model provides a uniform approach to regulation of the accounting profession.
Under Section 23 of the UAA, a CPA licensed in a jurisdiction with requirements essentially equivalent to those outlined in the UAA is deemed to be substantially equivalent. Requirements may include:
Obtaining 150 credit hours (150 college semester units or the equivalent) with a baccalaureate degree;
Minimum one year of CPA experience;
Passing the Uniform CPA Examination.
Uniform adoption of the UAA's substantial equivalency provision creates a system similar to the nation's driver's license program by providing CPAs with mobility while retaining and strengthening state boards’ ability to protect the public interest. The system enables consumers to receive timely services from the CPA best suited to the job, regardless of location, and without the hindrances of unnecessary filings, forms and increased costs that do not protect the public interest.
As of October 2012, a total of 49 out of the 50 states and the District of Columbia had passed mobility laws and were in the implementation and navigation phases. Only the Commonwealth of the Northern Mariana Islands, the Virgin Islands, Hawaii, Puerto Rico, and Guam have not passed mobility laws. A California mobility law went into effect July 1, 2013. The District of Columbia passed mobility laws effective on October 1, 2012.
AICPA membership
The CPA designation is granted by individual state boards, not the American Institute of Certified Public Accountants (AICPA). Membership in the AICPA is not obligatory for CPAs, although some CPAs do join. To become a full member of AICPA, the applicant must hold a valid CPA certificate or license from at least one of the fifty-five U.S. state/territory boards of accountancy; some additional requirements apply.
AICPA members approved a proposed bylaw amendment to make eligible for voting membership individuals who previously held a CPA certificate/license or have met all the requirements for CPA certification in accordance with the Uniform Accountancy Act (UAA). The AICPA announced its plan to accept applications from individuals meeting these criteria, beginning no later than January 1, 2011.
State CPA association membership
CPAs may also choose to become members of their local state association or society (also optional). Benefits of membership in a state CPA association range from deep discounts on seminars that qualify for continuing education credits to protecting the public and profession's interests by tracking and lobbying legislative issues that affect local state tax and financial planning issues.
CPAs who maintain state CPA society memberships are required to follow a society professional code of conduct (in addition to any code enforced by the state regulatory authority), further reassuring clients that the CPA is an ethical business professional conducting a legitimate business who can be trusted to handle confidential personal and business financial matters. State CPA associations also serve the community by providing information and resources about the CPA profession and welcome inquiries from students, business professionals and the public-at-large.
CPAs are not normally restricted to membership in the state CPA society in which they reside or hold a license or certificate. Many CPAs who live near state borders or who hold CPA status in more than one state may join more than one state CPA society.
State Associations
Missouri Society of Certified Public Accountants (MOCPA)
California Society of Certified Public Accountants (CalCPA)
Florida Institute of Certified Public Accountants (FICPA)
Indiana CPA Society (INCPAS)
Kentucky Society of CPAs (KyCPA)
Maryland Association of CPAs (MACPA)
Minnesota Society of Certified Public Accountants (MNCPA)
Nevada Society of Certified Public Accountants (NVCPA)
Pennsylvania Institute of Certified Public Accountants (PICPA)
Tennessee Society of Certified Public Accountants (TSCPA)
Wisconsin Institute of Certified Public Accountants (WICPA)
See also
Accountant
CPA Magazine
Institute of Certified Public Accountants in Ireland (CPA Ireland)
Certified Management Accountant by the Institute of Management Accountants
Certified National Accountant (Nigeria)
Institute of Public Accountants
Certified Practising Accountant (Australia)
Chartered Certified Accountant (ACCA)
Chartered Global Management Accountant
Legal liability of certified public accountants
References
External links
Directory of State CPA Societies
Accounting qualifications
Accounting in the United States | wiki |
Nissan 300 is a badge applied to different Nissan models available with a 3.0 L V6 engine:
Nissan 300C, a luxury car produced from 1984 to 1987
Nissan 300ZX, a sports car of the Z-car series produced from 1983 to 2000
See also
List of Nissan vehicles | wiki |
Many adaptations of The Lord of the Rings, an epic by the English author J. R. R. Tolkien, have been made in the media of film, radio, theatre, video games and recorded readings.
Motion pictures
Early attempts to adapt Tolkien's The Lord of the Rings were made by Walt Disney, William Snyder, Forrest J. Ackerman, Denis O'Dell (who considered Richard Lester to direct, but approached star directors David Lean, Stanley Kubrick and Michaelangelo Antonioni instead), Peter Shaffer, John Boorman and George Lucas. These attempts resulted in some unproduced concept art and scripts, original fantasy films like Excalibur and Willow and an animated short of The Hobbit.
Three cinema adaptations have been completed. The first was The Lord of the Rings by the American animator Ralph Bakshi in 1978, the first part of what was originally intended to be a two-part adaptation of the story. The second, The Return of the King in 1980, was a television special by Rankin-Bass. The third was The Lord of the Rings film trilogy by the New Zealand director Peter Jackson in the early 2000s, released in three installments as The Fellowship of the Ring, The Two Towers, and The Return of the King.
A Swedish live action television film, Sagan om ringen, inspired by the music album Music Inspired by Lord of the Rings by Bo Hansson was broadcast in 1971. A Finnish live action television miniseries, Hobitit, was broadcast in 1993 based on the events of The Hobbit and The Lord of the Rings. A live-action TV special of The Hobbit was produced in the Soviet Union in 1985, a pilot for an animated Hobbit series in 1991, and a live-action television play of The Fellowship of the Ring, Khraniteli has newly been discovered and uploaded in Russia's Channel 5 YouTube Channel in 2 parts. The adaptation had been aired in Russia once and was thought lost.
Radio
Tolkien's novel has repeatedly been adapted for radio both in the United States and in Europe, from soon after its publication in the 1950s onwards. In 1955 and 1956, the BBC broadcast The Lord of the Rings, a 12-part radio adaptation of the story. The Fellowship of the Rings was adapted as six 45-minute episodes, then The Two Towers and The Return of the King together were compressed into six 30-minute episodes. Tolkien disparaged this dramatisation, referring to the portrayal of Tom Bombadil as "dreadful" and complaining bitterly about several other aspects. The recordings were lost, but in 2022 the original scripts by the producer Terence Tiller, including a sheet with handwritten suggestions by Tolkien, were rediscovered in the BBC archives.
In 1981, BBC Radio 4 produced a new dramatisation of The Lord of the Rings in 26 half-hour stereo instalments. The script by Brian Sibley and Michael Bakewell attempts to be as faithful as possible to the original novel. It was a critical success and Ian Holm, who voiced Frodo Baggins in the radio serial, went on to play Bilbo Baggins in Peter Jackson's movie trilogy.
The New York radio station WBAI-FM broadcast a reading from the book in 1972, narrated by Baird Seales; since then, they have rebroadcast it annually.
A 1979 dramatisation was broadcast by National Public Radio in the United States. The series was produced by The Mind's Eye. It was produced by Bob Lewis and adapted for radio by Bernard Mayes. In 1981 the BBC broadcast its version in 26 half-hour instalments. It starred Ian Holm as Frodo Baggins, Bill Nighy as Sam Gamgee and Michael Hordern as Gandalf. In 1992 the German radio stations Südwestrundfunk and Westdeutscher Rundfunk broadcast Der Herr der Ringe, a 30-episode adaptation directed by Bernd Lau with music by Peter Zwetkoff. It had a cast including Hans Peter Hallwachs, Walter Renneisen, and Rufus Beck, and was narrated by Ernst Schröder. In 1999-2000 the Danish radio station Danmarks Radio broadcast Eventyret om Ringen, a Danish language retelling by Rune T. Kidde. The music was by The Tolkien Ensemble, Hedningarna, Sorten Muld and Kim Skovbye. In 2001, 2002 and 2003, the three volumes of the novel were adapted into a Slovak radio series, consisting of three annual series of fully cast radio plays, each of six episodes. The Hobbit character Bilbo Baggins served as the narrator. The eighteen episodes were produced and broadcast as a co-production between the public broadcaster Slovak Radio (now Radio and Television Slovakia) and the private broadcaster Rádio Twist (later known as Rádio Viva).
Stage
Several musical theatre adaptations, whether serious or parodic, have been made based on The Lord of the Rings; they have met with varying success. Full-length productions of each of The Fellowship of the Ring (2001), The Two Towers (2002), and The Return of the King (2003) were staged in Cincinnati, Ohio.
Lifeline Theatre in Chicago, Illinois, produced individual plays of each of the three books, with The Fellowship of the Ring in 1997, The Two Towers in 2000, and The Return of the King in 2001. Karen Tarjan and Ned Mochal were involved in adapting and directing the plays, with varying roles.
In 2006, a large-scale three-and-a-half-hour The Lord of the Rings musical was produced in Toronto. The expensive production lost money and closed six months later. It was edited for a production at the Theatre Royal Drury Lane in London, and ran from May 2007 until July 2008; The Guardian wrote that "at £25m, it was the most costly musical mistake in West End history".
A musical parody of The Fellowship of the Ring, titled Fellowship!, ran in Los Angeles for a stint on two occasions, coming back 3 years after its debut for a number of shows in the middle of 2009.
Video games
Numerous computer and video games have been inspired by J. R. R. Tolkien's works set in Middle-earth. Titles have been produced by studios such as Electronic Arts, Vivendi Games, Melbourne House, and Warner Bros. Interactive Entertainment.
Readings
The Library of Congress, which makes versions especially for the blind, recorded an unabridged version of The Lord of the Rings in 1967, narrated by Livingston Gilbert, on vinyl media. This version was taken out of circulation at the time of the recording of the 1978 version. It recorded a second unabridged version of The Lord of the Rings in 1978, narrated by Norman Barrs, on 4-track tape media. This version was taken out of circulation at the time of the recording of the 1999 version. It recorded a third unabridged version of The Lord of the Rings, A trip to Mordor in 1999, narrated by David Palmer, on 4-track tape media. This version is also available on the new digital players provided for Library of Congress patrons.
In 1990, the Australian actor Rob Inglis read and performed an unabridged version for Recorded Books in their New York studio. While not strictly a dramatisation, Inglis created voices for all the characters, and along with project producer Claudia Howard, he created music for all the songs, which he performed. The project took six weeks to record, not counting preparation time.
In 2021, the British actor Andy Serkis, who played Gollum in Peter Jackson's films, recorded an unabridged version of all three volumes of The Lord of the Rings for HarperCollins and Recorded Books.
References
External links
Official sites
The Lord of the Rings at Ralph Bakshi.com
Official site of the New Line Cinema films
Informational
The Lord of the Rings film trilogy at the Arts & Faith Top 100 Spiritually Significant Films list
John Boorman and Rospo Pallenberg's plans for an adaptation of The Lord of the Rings, from The One Ring message board | wiki |
Sweet is a basic taste sensation associated with sugars.
Sweet may also refer to:
Food
Candy or sweets
Confectionery or sweet
Dessert or sweet
Sweet (wine), a sweetness classification
Music
The Sweet, a 1970s British glam rock band
The Sweet (album) (1973)
Sweet (Chara album) (1991)
Sweet (Ken Mellons album) (2004)
"Sweet", a song by Annie from Don't Stop
"Sweet", a song by Common from The Dreamer/The Believer
People
Sweet (surname)
Sweet Charles Sherrell (born 1943), American bassist
Chun Jung-Hee or Sweet (born 1983), former Warcraft III player
Places
Sweet River, Jamaica
Sweet, Idaho, United States, an unincorporated community
Other uses
Sweet (company), a United States travel company
Sweet (film), a 2000 short film by James Pilkington starring Noel Fielding and Julian Barratt
Swedish ethyl acetate method, a method of chemical analysis
Sweet crude oil, petroleum with less than 0.42% sulfur
Sweet, a minor character in Buffy the Vampire Slayer
Sean "Sweet" Johnson, a character in Grand Theft Auto: San Andreas
SWEET transporters, a family of sugar transporters found in plants, animals, protozoans, and bacteria
See also
Sweets (disambiguation)
Swete, a surname
Swetes, Antigua, Antigua and Barbuda; also called "Sweet's"
Suite (disambiguation) | wiki |
Chiark may refer to:
The fictional Chiark Orbital in the Culture series by Iain M. Banks
chiark.greenend.org.uk, run by Ian Jackson and named after Chiark Orbital | wiki |
Fremont Glacier may refer to:
Fremont Glacier (Washington) in North Cascades National Park, Washington, USA
Lower Fremont Glacier in the Wind River Range, Wyoming, USA
Upper Fremont Glacier in the Wind River Range, Wyoming, USA | wiki |
Tribrach can refer to:
Tribrach (poetry), a metrical foot of three short syllables.
Tribrach (instrument), a device used in surveying for mounting an instrument on a surveyor's tripod. | wiki |
"Come On Back" is a song written and recorded by American country music artist Carlene Carter. It was released in September 1990 as the second single from her album I Fell in Love. The song reached number 3 on the Billboard Hot Country Singles & Tracks chart in January 1991.
Chart performance
Year-end charts
References
1990 singles
Carlene Carter songs
Songs written by Carlene Carter
Song recordings produced by Howie Epstein
Reprise Records singles
1990 songs | wiki |
Olympia Fields – wieś w Stanach Zjednoczonych, w stanie Illinois, w hrabstwie Cook.
Wsie w stanie Illinois | wiki |
Lifespan or life span may refer to:
Lifespan (film), 1976 film starring Klaus Kinski
Lifespan (album), 2004 album by Kris Davis
Lifespan (book), 2019 book by David Andrew Sinclair
Lifespan (video game), Atari 8-bit computer game
See also
Maximum life span, the maximum lifespan observed in a group
Life expectancy, the average lifespan expected of a group
Longevity, the average lifespan expected under ideal conditions
Lifetime (disambiguation) | wiki |
A whirlwind is a weather phenomenon in which a vortex of wind (a vertically oriented rotating column of air) forms due to instabilities and turbulence created by heating and flow (current) gradients. Whirlwinds occur all over the world and in any season.
Types
Whirlwinds are subdivided into two main types, the great (or major) whirlwinds, and the lesser (or minor) whirlwinds. The first category includes tornadoes, waterspouts, and landspouts. The range of atmospheric vortices constitute a continuum and are difficult to categorize definitively. Some lesser whirlwinds may sometimes form in a similar manner to greater whirlwinds with related increase in intensity. These intermediate types include the gustnado and the fire whirl. Other lesser whirlwinds include dust devils, as well as steam devils, snow devils, debris devils, leaf devils or hay devils, water devils, and shear eddies such as the mountainado and eddy whirlwinds.
Formation
A major whirlwind (such as a tornado) is formed from supercell thunderstorms (the most powerful type of thunderstorm) or other powerful storms. When the storms start to spin, they react with other high altitude winds, causing a funnel to spin. A cloud forms over the funnel, making it visible.
A minor whirlwind is created when local winds start to spin on the ground. This causes a funnel to form. The funnel moves over the ground, pushed by the winds that first formed it. The funnel picks up materials such as dust or snow as it moves over the ground, thus becoming visible.
Duration
Major whirlwinds last longer because they are formed from very powerful winds, and it is hard, though not impossible, to interrupt them. Minor whirlwinds are not as long-lived; the winds that form them do not last long, and when a minor whirlwind encounters an obstruction (a building, a house, a tree, etc.), its rotation is interrupted, as is the windflow into it, causing it to dissipate.
Associated weather
Supercell thunderstorms, other powerful storms, and strong winds are seen with major whirlwinds. Wind storms are commonly seen with minor whirlwinds. Also, small, semi-powerful “wind blasts” may be seen before some minor whirlwinds, which can come from a wind storm. These wind blasts can start to rotate and form minor whirlwinds. Winds from other small storms (such as rain storms and local thunderstorms) can cause minor whirlwinds to form. Like major whirlwinds, these minor whirlwinds can also be dangerous at times.
Similar phenomena
Eddies and vortices may form in any fluid. In water, a whirlpool is a similar phenomenon.
See also
Hurricane
External links
Fire whirlwind video September 11, 2012 Alice Springs Australia.
Severe Storm Definitions & Whirlwind Classification (TORRO)
Whirlwinds (TORRO)
A 'hay devil' from National Geographic
A longer version of the above but poorer quality
Severe weather and convection
Vortices
Meteorological phenomena | wiki |
Retroperistalsis is the reverse of the involuntary smooth muscle contractions of peristalsis. It usually occurs as a precursor to vomiting. Local irritation of the stomach, such as bacteria or food poisoning, activates the emetic center of the brain which in turn signals an imminent vomiting reflex. Retroperistalsis begins in the small intestine and pyloric sphincter. Food then moves in the opposite direction, often from the duodenum into the stomach.
Retroperistalsis occurs pathologically during vomiting and physiologically at the first part of the duodenum where it protects from high acidity of food, and also at the terminal ileum, where an amount of water and electrolytes are absorbed to assist defecation.
References
Digestive system | wiki |
Pancha Tattva may refer to:
Panchatattva (Tantra)
Pancha Tattva (Vaishnavism) | wiki |
A fortnight is a period of 14 days or alternatively half of a month.
Fortnight or Fortnightly may also refer to:
Fort Nightly, a 2007 album by White Rabbits
Fortnight (magazine), an Irish magazine published from 1970 to 2012
The Fortnightly Review, an English magazine published from 1865 to 1954
See also
Fortnite, a 2017 video game
14 Days (disambiguation)
Two weeks (disambiguation) | wiki |
A smile is a facial expression formed primarily by flexing the muscles at the sides of the mouth. Some smiles include a contraction of the muscles at the corner of the eyes, an action known as a Duchenne smile.
Among humans, a smile expresses delight, sociability, happiness, joy, or amusement. It is distinct from a similar but usually involuntary expression of anxiety known as a grimace. Although cross-cultural studies have shown that smiling is a means of communication throughout the world, there are large differences among different cultures, religions, and societies, with some using smiles to convey confusion or embarrassment.
Evolutionary background
Primatologist Signe Preuschoft traces the smile back over 30 million years of evolution to a "fear grin" stemming from monkeys and apes, who often used barely clenched teeth to portray to predators that they were harmless or to signal submission to more dominant group members. The smile may have evolved differently among species, especially among humans.
Social effects
Smiling seems to have a favorable influence upon others and makes one likable and more approachable. In the social context, smiling and laughter have different functions in the order of sequence in social situations:
Smiling is sometimes a pre-laughing device and is a common pattern for paving the way to laughter;
Smiling can be used as a response to laughter.
Smiling is a signaling system that evolved from a need to communicate information in many different forms. One of these is an advertisement of sexual interest. Female smiles are appealing to heterosexual males, increasing physical attractiveness and enhancing sex appeal. However, recent research indicates a man's smile may or may not be most effective in attracting heterosexual women, and that facial expressions such as pride or even shame might be more effective. The researchers did not explicitly study the role of smiles in other sexual preferences.
As reinforcement and manipulation
The influence of smiling on others is not necessarily benign. It may take the form of positive reinforcement, possibly for an underhand manipulative and abusive purpose.
Cultural differences
While smiling is perceived as a positive emotion most of the time, there are many cultures that perceive smiling as a negative expression and consider it unwelcoming. Too much smiling can be viewed as a sign of shallowness or dishonesty. In some parts of Asia, people may smile when they are embarrassed or in emotional pain. Some people may smile at others to indicate a friendly greeting. A smile may be reserved for close friends and family members. Many people in the former Soviet Union area consider smiling at strangers in public to be unusual and even suspicious behavior, or even a sign of stupidity.
Systematic large cross-cultural study on social perception of smiling individuals documented that in some cultures a smiling individual may be perceived as less intelligent than the same non-smiling individual (and that cultural uncertainty avoidance may explain these differences). Furthermore, the same study showed that corruption at the societal level may undermine the prosocial perception of smiling—in societies with high corruption indicators, trust toward smiling individuals is reduced.
There can also be gender differences. In the United States and Canada, women report men's telling them to smile. For example, Greg Rickford, a member of the Canadian Parliament told a female journalist to smile rather than answer the question she had asked. Biological anthropologist Helen Fisher states that, while this could be either caring or controlling behavior, such behavior is unlikely to be welcome.
Dimples
Cheek dimples are formed secondary to a bifid zygomaticus major muscle, whose fascial strands insert into the dermis and cause a dermal tethering effect. Dimples are genetically inherited and are a dominant trait. Having bilateral dimples (dimples in both cheeks) is the most common form of cheek dimples. A rarer form is the single dimple, which occurs on one side of the face only.
This bifid variation of the muscle originates as a single structure from the zygomatic bone. As it travels anteriorly, it then divides with a superior bundle that inserts in the typical position above the corner of the mouth. An inferior bundle inserts below the corner of the mouth. Dimples are analogous and how they form in cheeks varies from person to person. The shape of a person's face can affect the look and form as well: leptoprosopic (long and narrow) faces have long and narrow dimples, and eryprosopic (short and broad) faces have short, circular dimples. People with a mesoprosopic face are more likely to have dimples in their cheeks than any other face shape.
Duchenne smile
While conducting research on the physiology of facial expressions in the mid-19th century, French neurologist Guillaume Duchenne identified two distinct types of smiles. A Duchenne smile involves contraction of both the zygomatic major muscle (which raises the corners of the mouth) and the orbicularis oculi muscle (which raises the cheeks and forms crow's feet around the eyes). The Duchenne smile has been described as "smizing", as in "smiling with the eyes". An exaggerated Duchenne smile is sometimes associated with lying.
Non-Duchenne smile
A non-Duchenne smile involves only the zygomatic major muscle. According to Messenger et. al. "Research with adults initially indicated that joy was indexed by generic smiling, any smiling involving the raising of the lip corners by the zygomatic major .... More recent research suggests that smiling in which the muscle around the eye contracts, raising the cheeks high (Duchenne smiling), is uniquely associated with positive emotion."
The "Pan Am smile", also known as the "Botox smile", is the name given to a fake smile, in which only the zygomatic major muscle is voluntarily contracted to show politeness. It is named after the now-defunct airline Pan American World Airways, whose flight attendants would always flash every passenger the same perfunctory smile. Botox was introduced for cosmetic use in 2002. Chronic use of Botox injections to deal with eye wrinkle can result in the paralysis of the small muscles around the eyes, preventing the appearance of a Duchenne smile.
In animals
In animals, the baring of teeth is often used as a threat or warning display—known as a snarl—or a sign of submission. For chimpanzees, it can also be a sign of fear. However, not all animal displays of teeth convey negative acts or emotions. For example, Barbary macaques demonstrate an open mouth display as a sign of playfulness, which likely has similar roots and purposes as the human smile.
See also
References
Further reading
Ottenheimer, H.J. (2006). The anthropology of language: An introduction to linguistic anthropology. Belmont, CA: Thomson Wadsworh.
Cited in: Russell and Fernandez-Dols, eds. (1997).
Russell and Fernandez-Dols, eds. (1997). The Psychology of Facial Expression. Cambridge. .
External links
BBC News: Scanner shows unborn babies smile
Facial expressions
Laughter
Mouth
Happiness
Social influence | wiki |
While mixed martial arts is primarily a male dominated sport, it does have female athletes. For instance, Female competition in Japan includes promotions such as DEEP Jewels. Now defunct promotions that featured female fighters were Valkyrie, and Smackgirl. Professional mixed martial arts organizations in the United States that invite women to compete are industry leader Ultimate Fighting Championship, the all female Invicta Fighting Championships, Resurrection Fighting Alliance, Bellator Fighting Championships, and Legacy Fighting Championship. Now defunct promotions that featured female fighters were Strikeforce and EliteXC.
There has been a growing awareness of women in mixed martial arts due to popular female fighters and personalities such as Amanda Nunes, Megumi Fujii, Gina Carano, Cristiane "Cyborg" Santos, Ronda Rousey, Miesha Tate, Holly Holm and Joanna Jędrzejczyk and among others. Carano became known as "the face of women's MMA" after appearing in a number of EliteXC events. This was furthered by her appearances on MGM Television's 2008 revival of their game show American Gladiators.
The UFC's decision to allow female fighters in the organization, to promote the dominant fighter Ronda Rousey, is often cited as the reason women's mixed martial arts became known to the general public. Rousey won the Best Fighter ESPY Award at the 2015 ESPN ESPY award's, beating out noted fighters such as Floyd Mayweather Jr., and becoming the first UFC and MMA fighter to win the award.
History
In Japan, female competition has been documented since the mid-1990s. Influenced by female professional wrestling and kickboxing, the Smackgirl competition was formed in 2001 and became the only major all-female promotion in mixed martial arts. Other early successful Japanese female organizations included Ladies Legend Pro-Wrestling, ReMix (a predecessor to Smackgirl), U-Top Tournament, K-Grace, and AX.
The Rise of Women's MMA
Ronda Rousey was a female fighter who sparked the popularity of women fighters. When she signed with the UFC in 2012, female fighting was not very popular and was not considered a sport for women. Ronda Rousey was able to open many people's eyes and prove Dana White, the president of the UFC very wrong. Ronda Rousey was the face of UFC and the highest-paid fighter for a very long time. In addition to being an Olympic medalist, Rousey also won back-to-back Pan American Championship gold medals. It was surprising to many people how charismatic and talented Rousey actually was. Every day, female MMA fighters are becoming more popular and getting more viewers
United States
In the United States, prior to the success of The Ultimate Fighter reality show that launched mixed martial arts into the mainstream media, there was little major coverage of female competitions. Some early organizations who invited women to compete included, International Fighting Championships, SuperBrawl, King of the Cage, Rage in the Cage, Ring of Combat, Bas Rutten Invitational, and HOOKnSHOOT. The first recorded US female competition was at an IFC 4 between Becky Levi and Betty Fagan on March 28, 1997. This was soon followed by an IFC four women tournament sanctioned by the Louisiana Boxing and Wrestling Commission on September 5, 1997 in Baton Rouge. In 2002, HOOKnSHOOT promoted an all women's card labeled ‘Revolution’. It was headlined by Debi Purcell and Christine Van Fleet. In 2005 they held an all-women, one-night-only tournament featuring Julie Kedzie, Jan Finney, and Lisa Ellis. From the mid-2000s, more coverage came when organizations such as Strikeforce, EliteXC, Bellator Fighting Championships, and Shark Fights invited women to compete.
Following Zuffa's acquisition of Strikeforce in March 2011, there has been much speculation concerning the future of women's competition, in term both of relevance and popularity.
The next step was for the Ultimate Fighting Championship (UFC) to pick up women's MMA, however UFC President Dana White was resistant. He has said, "There is not enough depth to create a women's division."
However, Dana White warmed up to the idea of including women in the UFC and solely credits Ronda Rousey as the reason women are fighting in the UFC.
Europe and Japan
Outside Japan and the United States, female competition is almost exclusively found in minor local promotions. However, in Europe some major organizations have held select female competitions, including It's Showtime, Shooto Europe, Cage Warriors, and M-1 Global.
Africa
Africa's first female professional mixed martial arts bout was held in Johannesburg, South Africa in 2015. South Africa's Danella Eliasov defeated Zita Varju (Hungary) by first round submission.
Asia
ONE Championship is the leading MMA promotion in Asia and hosts many female professional mixed martial arts bouts.
Rule differentiation
The traditional MMA rules have often been adjusted for female competitions because of safety concerns. In Japan, ReMix prohibited ground-and-pound and featured a 20-second time limit for ground fighting. This rule remained following ReMix's 2001 re-branding as Smackgirl, though the time limit was extended to 30 seconds. The rule was abolished in 2008.
In the United States, women's bouts organised by EliteXC saw three-minute rounds while those of Strikeforce were originally of two minutes' duration. These lengths compare to the more usual five minutes for men. Strikeforce later changed this rule to allow for five-minute rounds.
Another form of rule differentiation is a change in both weight limits and weight classification. This has been seen in a number of organizations including, Strikeforce, Smackgirl, and Valkyrie.
While men are required to wear a groin protector, women are forbidden from doing so. Women must wear a top and chest protector, while men are allowed neither.
Milestones
First female MMA fight in United States held on March 28, 1997 by the International Fighting Championships between Becky Levi and Betty Fagan.
Strikeforce became the first major promotion in the United States to have held a female fight as the main event on August 15, 2009. The fight between Gina Carano and Cristiane Santos, known professionally as Cris Cyborg, attracted 856,000 viewers. Santos made history with her victory over Carano as she became the first Strikeforce Women's 145 lb Champion.
Invicta Fighting Championships in early 2012 became one of the first major women's pro mma organisations.
Ronda Rousey became the first woman fighter signed to the UFC on November 2012, and was promoted to the division's bantamweight champion. She successfully defended her title in the first UFC women's fight against Liz Carmouche at UFC 157.
Miesha Tate and Cat Zingano fought at the Ultimate Fighter 17 Finale on April 13.
On December 11, 2013 the UFC picked up the contracts of 11 female fighters to fill up their 115-pound division. The Strawweights took part in the 20th season of The Ultimate Fighter, the season winner will be the first UFC women's strawweight champion. Some of the fighters include Felice Herrig, Claudia Gadelha, Tecia Torres, Bec Hyatt, Joanne Calderwood, and even Invicta FC's Strawweight Champion Carla Esparza and many more.
Carla Esparza became the first UFC strawweight champion after defeating Rose Namajunas at The Ultimate Fighter: A Champion Will Be Crowned finale.
Esparza lost her title to Joanna Jędrzejczyk at UFC 185.
The most Important Moments in the MMA
There are many important moments that occurred with women's MMA. One of those moments was when Bellator added Women's tournaments, and this was important because it gave a place for top fighters in the smaller weight division to be broadcast. Another moment was when Ronda Rousey won the title because of the impact she had on many other women looking to be involved in this sport. Another very important fight was when Gina Carano fought Cris Cyborg since it was the first big women's MMA fight and the first time an MMA card was headlined by a women's fight. The implementation of Invicta FC was a very significant time period because female fighters had a place to call home and were able to fight on a consistent basis in their own weight class. One last important moment was when Primetime became the first mixed martial arts card to be broadcast on national television.
Disagreement and Pay Issues with Women's MMA
Since its inception the role of women in mixed martial arts has been a subject of debate. Some observers have treated women's competition as a spectacle and a taboo topic.
Mixed martial arts (MMA) fights have become increasingly popular among women. Women fighters needed to be represented and marketed with more equality for a while. The average pay for women at the time was $15,000, compared to men's $38,000 per fight, which led to a lot of women being frustrated with their pay. Paige VanZant who is an MMA fighter spoke out about wage inequality in 2019 and said she wanted more money to "keep bleeding and sacrificing for this sport". US women's soccer players took legal action over the fact that their pay is significantly lower than men's. During the UFC 241 event, the highest-paid man earned $700,000, while the highest-paid female fighter earned $30,000 according to FINCHANNEL statistics. The top female earner in 2020 was Amanda Nunes, who earned $350,000 plus $100,000 if she won the fight. Conor McGregor is thought to have gotten about $3 million for each of his most recent fights. Another male MMA fighter, Alistair Overeem has recently been paid $800,000 for each match he has. Dana White, who is the president of the UFC stated that he would never allow women to compete in his organization. Although, after observing how many viewers are watching women's fights, he has since acknowledged that female athletes are "very good." Women are requesting more money from the UFC as more viewers start to watch women's fights. Female MMA fighters' earning potential has grown as they gain popularity and recognition. Even though it has changed, the most well-liked male fighters like Conor Mcgregor continue to attract larger audiences and earn more money although it definitely won't be long until women are just as popular, and it is truly equal.
See also
Mixed martial arts
List of female mixed martial artists
References
Bibliography
Global Perspectives on Women in Combat Sports:Women Warriors around the World, Alex Channon, Palgrave Macmillan, August 2015, | wiki |
Helena Ducena Angelina (; ) foi uma nobre grega da Tessália e rainha-consorte da Sérvia. Seus pais eram e sua esposa Hipomona (filha do chefe tessálio valaco Tarona). Em ca. 1273/1276, Helena casou-se com o rei Estêvão Milutino , mas Milutino abandonou-a em ca. 1283.
Bibliografia
Bizantinos do século XIII
Mulheres do Império Bizantino
Sebastocratores bizantinos
Tessália na Idade Média
Dinastia Comneno Ducas
Família Ângelo
Dinastia nemânica
Rainhas consortes da Sérvia | wiki |
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