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overbudget and buggy; soon came the appalling news that the cost of software was overtaking that of hardware. Frederick P. Brooks, Jr., who managed the OS/360 software program at IBM, called large-system programming a "tar pit" and remarked, "Everyone seems to have been surprised by the stickiness of the problem." One ... |
Edsger W. Dijkstra's brief letter to the editor titled "Go to statement considered harmful." Structured programs were to be built out of subunits that have a single entrance point and a single exit (eschewing the goto command, which allows jumps into or out of the middle of a routine). Three such constructs were recomm... |
A or do B) and iteration (repeat A until some condition is satisfied). Corrado Böhm and Giuseppe Jacopini proved that these three idioms are sufficient to express essentially all programs. Structured programming came packaged with a number of related principles and imperatives. Top-down design and stepwise refinement u... |
in the details. Modularity called for self-contained units with simple interfaces between them. Encapsulation, or data hiding, required that the internal workings of a module be kept private, so that later changes to the module would not affect other areas of the program. All of these ideas have proved their worth and ... |
programmers from the tar pit. Nouns and Verbs The true history of software development is not a straight line but a meandering river with dozens of branches. Some of the tributaries—functional programming, declarative programming, methods based on formal proofs of correctness—are no less interesting than the mainstream... |
geometric figures. In a non-OOP environment, you might begin by writing a series of procedures with names such as rotate, scale, reflect, calculate-area, calculate-perimeter. Each of these verblike procedures could be applied to triangles, squares, circles and many other shapes; the figures themselves are nounlike enti... |
of three vertices, where each vertex is a pair of x and y coordinates. Applying the rotate procedure to this data structure would alter the coordinates and thereby turn the triangle. What's the matter with this scheme? One likely source of trouble is that the procedures and the data structures are separate but interdep... |
using a linked list of points instead of an array—you must remember to change all the procedures that might ever be applied to a triangle. Also, choosing different representations for some of the figures becomes awkward. If you describe a circle in terms of a center and a radius rather than a set of vertices, all the p... |
special case. Yet another pitfall is that the data structures are public property, and the procedures that share them may not always play nicely together. A figure altered by one procedure might no longer be valid input for another. Object-oriented programming addresses these issues by packing both data and procedures—... |
some data structure representing a three-sided shape, but it would also include the procedures (called methods in this context) for acting on the data. To rotate a triangle, you send a message to the triangle object, telling it to rotate itself. Sending and receiving messages is the only way objects communicate with on... |
only the object's own methods know about the internal data structures, it's easier to keep them in sync. This scheme would not have much appeal if every time you wanted to create a triangle, you had to write out all the necessary data structures and methods—but that's not how it works. You define the class triangle jus... |
of the class. A mechanism called inheritance takes this idea a step further. You might define a more-general class polygon, which would have triangle as a subclass, along with other subclasses such as quadrilateral, pentagon and hexagon. Some methods would be common to all polygons; one example is the calculation of pe... |
matter how many sides there are. If you define the method calculate-perimeter in the class polygon, all the subclasses inherit this code. Object-oriented programming traces its heritage back to simula, a programming language devised in the 1960s by Ole-Johan Dahl and Kristen Nygaard. Some object-oriented ideas were als... |
of inspiration. The various threads came together when Alan Kay and his colleagues created the Smalltalk language at the Xerox Palo Alto Research Center in the 1970s. Within a decade several more object-oriented languages were in use, most notably Bjarne Stroustrup's C++, and later Java. Object-oriented features have a... |
are written, there has also been a major shift in the nature of the programs themselves. In the software-engineering literature of the 1960s and '70s, example programs tend to have a sausage-grinder structure: Inputs enter at one end, and outputs emerge at the other. An example is a compiler, which transforms source co... |
but they are no longer the center of attention. The emphasis now is on interactive software with a graphical user interface. Programming manuals for object-oriented languages are all about windows and menus and mouse clicks. In other words, OOP is not just a different solution; it also solves a different problem. Aspec... |
object-oriented programming; they seek to refine or improve or reinvigorate it. A case in point is aspect-oriented programming, or AOP. The classic challenge in writing object-oriented programs is finding the right decomposition into classes and objects. Returning to the example of a program for playing with geometric ... |
also a pentagon: . And so is this: . To accommodate the differences between these figures, you could introduce subclasses of pentagon—perhaps named convex-pentagon, non-convex-pentagon and five-pointed-star. But then you would have to do the same thing for hexagons, heptagons and so forth, which soon becomes tedious. M... |
polygons but to no others. An alternative decomposition would divide the polygon class into convex-polygon and non-convex-polygon, then subdivide the latter class into simple-polygon and self-intersecting-polygon. With this choice, however, you lose the ability to address all five-sided figures as a group. One solution... |
a subclass both of pentagon and of self-intersecting-polygon and could inherit methods from both. The wisdom of this arrangement is a matter of eternal controversy in the OOP community. Aspect-oriented programming takes another approach to dealing with "crosscutting" issues that cannot easily be arranged in a treelike ... |
time a figure is moved or modified. The straightforward OOP solution is to have each method that changes the appearance of a figure (such as rotate or scale) send a message to a display-manager object, telling the display what needs to be redrawn. But hundreds of methods could send such messages. Even apart from the bo... |
there is the worry that the interface to the display manager might change someday, requiring many methods to be revised. The AOP answer is to isolate the display-update "aspect" of the program in a module of its own. The programmer writes one instance of the code that calls for a display update, along with a specificat... |
is to be invoked—for example, whenever a rotate method is executed. Then even though the text of the rotate method does not mention display updating, the appropriate message is sent at the appropriate time. An AOP system called AspectJ, developed by Gregor Kiczales and a group of colleagues at Xerox PARC, works as an e... |
implementing ubiquitous tasks such as error-handling, the logging of events, and synchronizing multiple threads of execution, which might otherwise be scattered throughout a program. But there are dissenting views. Jörg Kienzle and Rachid Guerraoui report on an attempt to build a transaction- processing system with Asp... |
cannot debit one account without crediting another). They found it difficult to cleanly isolate this property as an aspect. Surely the most obvious place to look for help with programming a computer is the computer itself. If Fortran can be compiled into machine code, then why not transform some higher-level descriptio... |
lives on under names such as generative programming, metaprogramming and intentional programming. In general, fully automatic programming remains beyond our reach, but there is one area where the idea has solid theoretical underpinnings as well as a record of practical success: in the building of compilers. Instead of ... |
for the language and then generate the compiler with a program called a compiler compiler. (The best-known of these programs is Yacc, which stands for "yet another compiler compiler.") Generative programming would adapt this model to other domains. For example, a program generator for the kind of software that controls... |
produce an appropriately specialized program. Another kind of generator might assemble "protocol stacks" for computer networking. Krzysztof Czarnecki and Ulrich W. Eisenecker compare a generative-programming system to a factory for manufacturing automobiles. Building the factory is more work than building a single car ... |
many different models just by changing the specifications. Likewise generative programming would create families of programs tailored to diverse circumstances but all assembled from similar components. The Quality Without a Name Another new programming methodology draws its inspiration from an unexpected quarter. Altho... |
software designers became disciples of a bricks-and-steel architect, Christopher Alexander. Even Alexander was surprised. Alexander is known for the enigmatic thesis that well-designed buildings and towns must have "the quality without a name." He explains: "The fact that this quality cannot be named does not mean that... |
answer your question? Even if the quality had a name, it's not clear how one would turn it into a prescription for building good houses—or good software. Fortunately, Alexander is more explicit elsewhere in his writings. He urges architects to exploit recurrent patterns observed in both problems and solutions. For the ... |
probably going to look something like a front porch. Taken over into the world of software, this approach leads to a catalogue of design patterns for solving specific, recurring problems in object-oriented programming. For example, a pattern named Bridge deals with the problem of setting up communications between two o... |
written. A pattern named Composite handles the situation where a single object and a collection of multiple objects have to be given the same status, as is often the case with files and directories of files. Over the past 10 years a sizable community has grown up around the pattern idea. There are dozens of books, web ... |
Languages of Programming, or PLoP. Compared with earlier reform movements in computing, the pattern community sounds a little unfocused and New Age. Whereas structured programming was founded on a proof that three specific structures suffice to express all algorithms, there is nothing resembling such a proof to justify... |
whole idea of proofs seems to be out of favor in the pattern community. Software Jeremiahs usually preach that programming should be an engineering profession, guided by standards analogous to building codes, or else it should be a branch of applied mathematics, with programs constructed like mathematical proofs. The p... |
or stonemasons—stewards of a body of knowledge gained by experience and passed along by tradition and apprenticeship. This is a movement of practitioners, not academics. Pattern advocates express particular contempt for the notion that programming might someday be taken over entirely by the computer. Automating a craft... |
like the ranting of a fringe group, but pattern methods have been adopted in several large organizations producing large—and successful—software systems. (When you make a phone call, you may well be relying on the work of programmers seeking out the quality without a name.) Moreover, beyond the rhetoric, the writings o... |
is on the radical fringe, how far out is extreme programming (or, as it is sometimes spelled, eXtreme programming)? For the leaders of this movement, the issue is not so much the nature of the software itself but the way programming projects are organized and managed. They want to peel away layers of bureaucracy and je... |
review and documentation that slow down software development. Just let programmers program! The recommended protocol is to work in pairs, two programmers huddling over a single keyboard, checking their own work as they go along. Is it a fad? A cult? Although the name may evoke a culture of body piercing and bungee jump... |
pinstriped suits. The first major project completed under the method was a payroll system for a transnational automobile manufacturer. Ask Me About My OOP Diet Frederick Brooks, who wrote of the tar pit in the 1960s, followed up in 1987 with an essay on the futility of seeking a "silver bullet," a single magical remedy... |
programming might alleviate "accidental difficulties" of software development, he said, but the essential complexity cannot be wished away. This pronouncement that the disease is incurable made everyone feel better. But it deterred no one from proposing remedies. After several weeks' immersion in the how-to-program lit... |
In saying this I mean no disrespect to either genre. Most diet books, somewhere deep inside, offer sound advice: Eat less, exercise more. Most programming manuals also give wise counsel: Modularize, encapsulate. But surveying the hundreds of titles in both categories leaves me with a nagging doubt: The very multiplicit... |
we'd all have better software, if there were just one true diet, and one true programming methodology? Maybe that day will come. In the meantime, I'm going on a spaghetti-code diet. © Brian Hayes |
Each month there is a special South Carolina token or medal that is highlighted as the Token or Medal of the Month. This month we will showcase an interesting early 20th century trade token from the city of Charleston. The city of Charleston has always played a significant role in |
the history of the state of South Carolina. From its beginnings in 1670 as a small colonial settlement at the confluence of the Ashley and Cooper Rivers, through its growing importance as a seaport for the fledgling nation, to its part as the incendiary flashpoint in the sectional conflict which |
became the Civil War, the city has enjoyed a prominence that seemingly lifted it above similar communities in the state. It is no small wonder then, that some of its citizens thought the city to occupy a pedestal raised above its South Carolina neighbors. It was this feeling of superiority |
that occasionally led some Charlestonians to consider themselves immune from the laws and social mores governing the rest of the state. And this sentiment, in turn, gave rise to the issuance of this month's token, which so publicly flaunted Charleston's opposition to the state dispensary law and the temperance movement |
behind it. On its surface, the 29mm aluminum token shown above does not appear to carry any hint of its true nature. The innocuous inscription on the obverse reads GOOD FOR 5¢ IN TRADE AT CHICCO'S CAFE. The pictorial of the blindfolded tiger on the reverse, however, is a blatant |
advertisement for the "supposedly" clandestine saloon which Vincent Chicco operated in conjunction with his cafe. And, as such, the token speaks volumes on Charleston's open opposition to the state legislature's attempts to outlaw saloons and the sale of liquor by the drink in the late 1890s and early 1900s. During |
the aforementioned time period hundreds of "blind tigers," as they were commonly called, sprung up in Charleston and other cities in South Carolina. The illegal drinking establishments were a logical response to Governor Ben Tillman's attempt to legislate the drinking habits of a populace which liked its liquor. Tillma... |
much difficulty in controlling the "blind tigers" across the state, but especially so in the city of Charleston. Several times during his tenure in office he had to send out state constables to arrest any proprietors they could catch selling alcohol illegally. Vincent Chicco was one of the first people |
arrested after the enactment of Tillman's dispensary bill. A scant two weeks after the bill became law, Chicco was arrested and brought before a judge for illegal liquor sales. The details of his arrest and subsequent legal proceedings were covered prominently in the Charleston newspapers and Chicco's case became infam... |
Despite his brush with the law, he continued to sell alcohol to his customers in open defiance of the dispensary law and was subsequently arrested at least three times, in 1901, 1902, and 1903. Chicco apparently operated more than one clandestine saloon, and became known as the "King of the |
Blind Tigers." His main base of operations was at 83 Market Street, where he and his growing family lived in an apartment above the premises. At times Chicco's business was listed in the city directories as a grocery, a delicatessen, a cafe, and a restaurant. Prior to July 1893, when |
the dispensary act came into effect, Chicco was listed as a saloonkeeper. In 1894 and beyond, his business was never again described as a saloon, but his advertisements in the city directories certainly made it known that he sold wines and liquors. Chicco parlayed his notoriety for opposing the dispensary |
law into his election to the Charleston City Council as alderman for his ward. He was elected to five consecutive terms and for his earnestness in representing the members of his district he gained the unofficial epithet "Mayor of Ward 3." Chicco died in 1928 at the age of 78. |
His obituary in the Charleston newspaper characterized him as "possessing a forceful personality" and a "raconteur of ability." The newspaper mentioned his emigration to this country from Italy as a teenager after a short stint as a merchant seaman. Chicco then worked on one of the local railroads for a |
short period, after which he was employed as a policeman for the city of Charleston. He started his saloon business in 1892. He married Miss Mary Ann Burke of Charleston and had four children, Joseph, Vincent, Jr., Natalie, and an unidentified daughter. Incidentally, the term "blind tiger" as a synonym |
for an illegal drinking establishment can be traced back to the 1850s. A sister term "blind pig" dates from the 1870s. The terms derive from clandestine establishments that would advertise exotic animals on their window blinds, charging admission to see the said animals, which of course were not inside. Once |
admitted, patrons were then served with the illegal refreshment of their choice. The following limerick summarizes the ruse: On the store, though behind it you'd find Neither bengal nor cat, Just a liquor-filled vat And the patrons who paid didn't mind. Copyright 2006 by Tony Chibbaro. The South Carolina Dispensary |
& Embossed S.C. Whiskey Bottles & Jugs, 1865-1915 by Harvey S. Teal and Rita Foster Wallace, Midlands Printing Company, Camden, S.C., 2005. South Carolina Postcards, Volume I, Charleston, Berkeley, and Dorchester Counties by Howard Woody and Thomas L. Johnson, Arcadia Publishing Company, Charleston, S.C., 1997. The Red... |
Reaction to the South Carolina Dispensary System by Helen Glenn Smith, published in Chrestomathy: Annual Review of Undergraduate Research, School of Humanities and Social Sciences, College of Charleston, Volume 4, 2005: pp 195-217, College of Charleston, 2005. Chicco Funeral This Afternoon in News & Courier, October 26... |
a description of these standard references, please click on this link: Books. Token or Medal of the Month Main Page A Short History of Token Use in South Carolina South Carolina Trade Tokens for Sale - Page 1 South Carolina Trade Tokens for Sale - Page 2 Other South Carolina |
March 2003 | Monitor on Psychology | Vol. 34 No. 3 COVER: Cover topic: Anger - When anger's a plus Despite its mixed reputation, anger can play a constructive role at home, at work and in the national consciousness, psychologists are finding - Angry thoughts, at-risk hearts Researchers are exploring whether angry and h... |
their risk for poor cardiovascular health. - Hostility associated with immune function Aggression and hostility can affect tumor necrosis factor — a protein that is released by immune cells and other tissues. - 'Goo, gaa, grr?' Researchers are still looking for consensus on how and when anger first appears in infants. ... |
understand how men and women experience and express anger. - Advances in anger management Researchers and practitioners are examining what works best for managing problem anger. Honeybees can use short-term memory to alternate between two food sources, a new study suggests. - Study shows high rates of mental disorders ... |
disasters - Psychologist/engineer team builds robot that senses emotions - P. Kennedy will receive award at State Leadership Conference - Foundation accepting applications for Seligman positive psychology award - Study examines neural correlates of sympathy - Even hands-free cell phones may impair driving - Members exp... |
meetings Allegations of politicization are threatening the credibility of the federal government's scientific advisory committees. HIPAA's minimum necessary requirement was created to limit the amount of patient information that managed-care companies can request. A psychosocial treatment model at Walter Reed Army Medi... |
are helping them overcome the academic, social and cognitive obstacles that result from the disease and its treatments. A new APA interdivisional coalition aims to showcase psychology's research findings on education to the public and policy-makers. Is the nation's rise in nontraditional faculty for better or worse? Ps... |
Organizers hope that changes introduced at APA's 2002 Annual Convention will pave the way to increased attendance at future conventions. Interdisciplinary psychology programs focused on the underserved have secured $2 million in federal funding. Nominate your colleagues now for next year's Annual Convention. PUBLIC POL... |
Thursday, July 19, 2012 Come learn about a local endangered species. On August 8th my wife Pam and I will be part of a panel discussion at the Aquarium of the Pacific on a population of an endangered species that |
has chosen an improbable environmental niche in which to survive, the Green Sea Turtles of the San Gabriel River. Not much is known about the Green Sea Turtles that take refuge in the warm water produced by power-plants on the |
river that provide electricity to parts of Los Angeles and Orange County. These turtles are more normally associated with the warmer waters of Mexico and Hawaii. Dan Lawson of NOAA, Pam and the Aquarium vet Lance Adams will talk about |
the recent research on these animals and the rehabilitation and tracking of stranded turtles. Many of my sea turtle images will be used in the talks and I’ll also be part of the panel discussion. Since 2008 my wife Pam |
and I have been making regular treks to the San Gabriel River to gather information on these urban sea turtles. Pam taking notes on turtle sightings and incidental sightings of other wildlife while I photograph the brief instances that these |
sea turtles are at the surface. The Aquarium shares the data that we gather with the NOAA’s National Marine Fisheries Service. How hard is it to photograph an urban sea turtle in the murky waters of the San Gabriel River? |
Unlike the sea lions and sea otters that I work with at the Aquarium I can’t tell these wild sea turtles to come up exactly when and where I want them to. To give you an idea of the short |
window of opportunity I have while trying to photograph these turtles try this exercise. Place your camera in your right hand and hold it at your waist. Take a coin and place it on your left hand thumb in a |
flipping position. Flip the coin in the air while at the same time bringing your camera up to your eyes. Before the coin hits the ground you have to find it in your viewfinder, focus and shoot a picture of |
it. That’s about how much time you have to photograph a sea turtle when it surfaces, takes a breath and dives. Fortunately I do have a way of increasing my chances of getting a good shot of a sea turtle. |
When photographing any animal it helps to know your subjects. When the Aquarium of the Pacific opened in 1998 one of my duties along with taking care of the pinniped was to help out in caring for the four green |
sea turtles then on exhibit. This experience helps me understand a little bit of turtle behavior and helps me predict when and where they may surface in the river. I basically figure out a spot in the river where there |
is a high probability of a sea turtle surfacing, the approximate time between surfacing and hold my camera in a ready position in anticipation. It seems to work. Come on down to the Aquarium of the Pacific on Wednesday August |
8th and learn more about these local urban sea turtles. Have Something to Say? Leave a Comment! All blogs and comments represent the views of the individual authors and not necessarily those of the Aquarium. |
The Douglasfir is to the world of trees what a decathlon winner is to the Olympics. This tree is an all-around champion. It is one of our most important lumber species, a magnificent ornamental tree, and one of the most |
popular Christmas trees in America. Additionally, a large number of bird and animal species find shelter and food in its majestic foliage. This magnificent evergreen has a dense, cone-shape when young becoming more open and pyramid-shaped with maturity. It has |
a straight trunk with thin, smooth bark with resin blisters when young becoming thicker and furrowed on older trees. It reaches 40'-80', 12'-20' spread in the home landscape to over 200' in natural conditions. Coast Douglasfir needles are a dark |
yellow green although on some trees bluish green. In Rocky Mountain Douglasfir, the needles are blue green, but occasionally are yellowish green. The light brown, 3"-4" cones grow downward on the branches with distinctive 3-pointed bracts protruding from the between |
the scales. The Coast Douglasfir grows best in deep, moist, well drained, acid or neutral soil with atmospheric moisture, but the hardier Rocky Mountain variety is found in its native range on rocky mountain slopes. It does not tolerate dry, |
poor soils, and breakage is common on the side exposed to high winds. (zones 4-6) Douglasfir seeds are used by blue grouse,songbirds, squirrels, rabbits, and other rodents and small animals. Antelope, deer, elk, mountain goats, and mountain sheep eat the |
twigs and foliage. It provides excellent cover for a wide range of animals. While the Douglasfir may have first been introduced to cultivation by botanist-explorer David Douglas in 1826, its importance to American history continues unabated. As well as being |
the country's top source of lumber today, the Douglasfir also helped settle the West, providing railroad ties and telephone/telegraph poles. The Douglasfir was crucial to American soldiers in World War II as well, being used for everything from GIs' foot |
lockers to portable huts and even the rails of stretchers that carried many a soldier from battle. But perhaps one contribution of the Douglasfir symbolizes its place in America's evolving history more than any other. When in 1925 the time |
came to restore the masts of "Old Ironsides," the USS Constitution, sufficiently grand White Pine trees could no longer be found. Today, Old Ironsides proudly sails in the Boston Navy Yard under the power of three Douglasfir masts. There are |
two geographical varieties of Douglasfir: Coast Douglasfir, Pseudotsuga menziesii var. menziesii native to British Columbia along the Pacific coast to central California and western Nevada; Rocky Mountain Douglasfir native to the inland mountains of the Pacific Northwest and the Rocky |
Mountains from central British Columbia south to northern and central Mexico. The Coastal variety is faster growing, long-lived, and can reach over 300' tall. The needles are usually a dark yellow-green although some trees they may be bluish green. Rocky |
Mountain Douglasfir, Pseudotsuga menziesii var. glauca is hardier, slower growing, shorter lived and seldom grows over 130' tall. The needles are shorter and bluish green although in some trees may be yellowish green. The cones are barely 3" in length |
with bracts bent upwards. Douglasfir is written as one word or hyphenated to show it is not a true fir. Sensitive to drought conditions; requires good drainage. The needles are spiral, simple, 1-1/2 inches long, shining, shade of green depends |
upon the variety, two bands of stomata beneath. Coast Douglasfir has dark yellow-green, occasionally bluish-green needles. Rocky Mountain Douglasfir has shorter, bluish-green, occasionally yellowish green needles. male is red female is green with prominent bracts The light brown, oval, pendulous |
SAN MARINO, CA.- Drawing on the unparalleled manuscripts collection on the topic held by The Huntington Library, Art Collections, and Botanical Gardens , a major exhibition illuminates the remarkable changes wrought in the United States by the planning, construction, and completion of the transcontinental railroad. Vis... |
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