will, for convenience, be referred to herein as a sensor or as an actuator, but it will be understood that an actuator may function as a sensor, and vice versa. such actuators may take several forms, as will be described below, and in one form may incorporate partially oxidized silicon beams fabricated by the process described in copending u. s. patent application ser. no. 08 / 383, 524 of noel c. macdonald and ali jazairy, filed feb. 3, 1995, and entitled " masking process for fabricating ultra - high aspect ratio, wafer - free, micro - opto - electromechanical structures ", now u. s. pat. no. 5, 628, 917, the disclosure of which is hereby incorporated herein by reference. in the embodiment of the invention illustrated in figs. 1 and 2, the moment arm 12 has a stepped shape of decreasing width and is made up of a grid of individual longitudinal and lateral beams 58 having high aspect ratios to provide the desired rigidity, and thus the high spring constant, needed to provide the desired accuracy of measurement of applied forces at tip 23. near the base 14 of the moment arm 12, the arm is formed with a relatively wide region 60 which steps down at shoulder 62 to a second, slightly narrower region 64 at a selected distance along axis 22 from the base 14. region 64, in turn, steps down at shoulder 66 to a still narrower region 68 and again steps down at shoulder 70 to the narrowest region 72 on which the tip 23 is mounted at progressively distances along axis 22. the wide, stepped - down, elongated shape gives lateral stability to the moment arm 12 ( in the x - y plane ) so that it is relatively unaffected by lateral vibrations. the height of each beam, and thus of each region of the moment arm, as indicated by arrow 74, is sufficient to provide vertical rigidity, and to provide a relatively large height to width ratio, or aspect ratio, for each component beam in the structure. it will be apparent, of course, that numerous variations of this overall shape of the moment arm may be used while still providing the desired stability and rigidity for the arm. in the preferred embodiment, the arm 12 is secured to the torsional support beam 16 by a plurality of longitudinally extending connector beams 76, 77, 78, and 79 ( fig. 1 ). these connector beams are formed integrally with the


or transistors may be provided to detect motion of the cantilever in various directions. torsional resonators fabricated using the scream technique with k. sup. θ. sub. z equal to about 0. 3 n / m have achieved q values of 10. sup. 5 in a vacuum. a model of the present invention was constructed in accordance with fig. 1, with the beam width a equal to 1. 5 micrometers, the beam height b equal to 12. 3 micrometers, the distance ( l. sub. t ) equal to 50 micrometers and the distance ( l. sub. c ) equal to 950 micrometers. this structure produced a spring constant of 2. 58. times. 10. sup. - 2 n / m. furthermore, the resonant frequency of the torsional cantilever was experimentally measured at 1. 4 khz. the torsional rigidity was then determined, using the following relationship : # # equ5 # # where κ is the torsional rigidity and i is the moment of inertia. the known geometry of the device and the densities of the materials permit calculation of the rotational moment of inertia i = 2. 55. times. 10. sup. - 16 kg m. sup. 2. the resulting torsional rigidity is κ = 1. 97. times. 10. sup. - 8 n / m, which means that experimentally k. sup. θ. sub. z = κ / l. sub. c. sup. 2 = 2. 18. times. 10. sup. - 2 n / m. fig. 8 illustrates a modification of the cantilever device of figs. 1 and 2, wherein the counterweight 26 is replaced by a second cantilever moment arm 120 which is a duplicate of moment arm 12 and is coplanar, but extending on the opposite side of support beam 16. the cantilever moment arm 120 includes segments 122, 124, 126, and 128 which correspond to segments 60, 64, 68, and 72 of moment arm 12, with the cantilever structure extending over electrode 54 ' on the floor 38 of cavity 34. the symmetric design of fig. 8 provides improved results for applications such as in a scanning force microscope, since the moment arms of the two cantilevers about support beam 16 may be more precisely balanced. however, the asymmetric design of figs


the symmetric design of fig. 8 provides improved results for applications such as in a scanning force microscope, since the moment arms of the two cantilevers about support beam 16 may be more precisely balanced. however, the asymmetric design of figs. 1 and 2 may provide improved results for some sensor applications such as in an accelerometer. as with figs. 1 and 2, the electrodes 54 and 54 ' beneath the structure are used to move the cantilever in the vertical, or z, direction or to detect motion, or both. a still further embodiment of the invention is illustrated in figs. 9 and 10, wherein the cantilever device 10 of figs. 1 and 2 is provided with electrodes adjacent the torsional support beam 16 for controlling twisting of the beam under the torsional forces applied by the cantilever moment arm 12 and the counterweight 26. in this illustration, the relative positions of the arm 12 and counterweight 26 with respect to beam 16 are reversed. as illustrated, a first pair of electrodes 140, 142 is placed adjacent end 30 of beam 16 while a second pair of electrodes 144, 146 is placed adjacent end 32 of beam 16. as the support beam 16 is twisted under a torsional force, as illustrated in dotted lines at 16 ' in fig. 10, the upper edge 148 of beam 16 approaches electrode 142 and the lower edge 150 approaches electrode 140. a voltage applied to the electrodes 140 and 142, such as the voltage v relative to the voltage on beam 16, will attract the respective edges 148 and 150 of beam 16, causing the beam to twist further, so that the applied voltage can be used to reduce the spring constant of the cantilever. a variable voltage allows adjustment of the spring constant. it will be understood that the voltage may be applied to the electrodes 140, 142, and 144, 146 by way of integrated circuits fabricated on the substrate 18, such as circuits generally indicated at 152 and 154 in fig. 9, connected by way of conductors 156, 158, and 160, 162, respectively. these electrodes and conductors may be fabricated in accordance with the scream - i process described above. it has been found that the planar configuration of the cantilever moment arms 12 and 120 illustrated in the preceding figures may be subject to some in - plane twisting. in order to sense such twisting, a plurality of comb - type sensor sets 170, 172, 174, and 176 may be provided, as illustrated


and 220 ' with respect to the stationary capacitor electrodes on fingers 222 and 222 ' respectively, can be measured to detect vertical motion of a tip mounted on either of the cantilever arms 202 and 204, in the manner described above. similarly, by selectively applying voltages between adjacent electrodes, the arms 202 and 204 can be moved, or their response characteristics varied. modifications of the comb - type drive of figs. 11 and 12 are illustrated in figs. 13 - 15, wherein moveable and fixed interleaved fingers 240 and 242, which correspond to fingers 220 and 222 in fig. 12, are fabricated by the process of u. s. pat. no. 5, 628, 917 described above. this process does not result in metal - coated electrode fingers, but instead permits fabrication of partially oxidized released, or movable, silicon fingers, such as the partially oxidized fingers 240 in fig. 13, having their upper portions 244 oxidized, with the lower portions 246 remaining as silicon. alternatively, as illustrated in fig. 14, the upper portions 248 of the fixed silicon fingers 242 can be oxidized, with the lower portions 250 remaining silicon. a voltage v may be applied across the silicon portions of the adjacent fingers to produce an asymmetric electric field between them which will result in relative motion of the fingers. as will be explained in greater detail below, the application of a negative voltage to the stationary fingers 242 and a positive voltage to fingers 240 in fig. 13 will result in an asymmetric field which will produce an upward force on the movable fingers, while the same voltage applied to the device of fig. 14 will result in a downward force on the movable fingers. in the embodiment of fig. 15, the interleaved fingers are provided with alternating oxidized and non - oxidized segments, the movable silicon fingers 240 including oxidized ( silicon dioxide ) segments 252, and the fixed silicon fingers 242 including oxidized ( silicon dioxide ) segments 254. the oxidized segments on each finger are aligned with non - oxidized segments on adjacent fingers, so that by controlling the polarity of the voltages applied to the individual fingers, either upward or downward motion of the movable fingers can be achieved. fig. 16 illustrates another embodiment of the invention wherein two cantilever moment arms 260 and 262 are mounted within the cavity 34 in substrate 18, in the manner described above. in this embo


of the movable fingers can be achieved. fig. 16 illustrates another embodiment of the invention wherein two cantilever moment arms 260 and 262 are mounted within the cavity 34 in substrate 18, in the manner described above. in this embodiment, cantilever arms 260 and 262 both incorporate longitudinal interleaved sets of capacitor plates of the type illustrated in fig. 12, cantilever arm 260 including capacitors sets 264 and 266, and cantilever arm 262 incorporating capacitor sets 268 and 270 in place of the underlying electrodes utilized in previous embodiments. these capacitive electrode sets are used to sense the vertical motion of the cantilever arms 260 and 262, in the manner previously described, when the arms pivot about support beam 16 in response to the applied force or when both beams move in the same direction to deflect the beam 16. in addition, the device of fig. 16 incorporates sets of stabilizing comb capacitors to prevent or to compensate for in - plane twisting, cantilever arm 260 including stabilizing actuator sets 272 and 274, and cantilever arm 262 utilizing stabilizer actuator sets 276 and 278. the stabilizer actuators preferably are capacitive, in the manner previously described. fig. 17 is a diagrammatic illustration of one use of the torsionally - mounted cantilever device of the invention in an atomic force microscope. as illustrated, the cantilever device 290, which may be any one of the cantilever devices described above, is mounted adjacent to the surface 292 of a sample 294 that is to be scanned. the sample is mounted on a scanning table 296 which may be driven, as by conventional piezoelectric electric drivers, in an xy plane beneath and parallel to the cantilever 290. the sample should also be adjustable in the z direction to move it into proximity with a sensor tip 298 carried by the cantilever. when the tip is positioned very close to the surface of sample 294, the tip will interact with the material of the surface to produce deflection of the cantilever 290, as is known in the art of atomic force microscopes. the deflection of the cantilever may be detected by sensor 300, which may be any of the actuator / sensor devices described above, to produce an output signal through a feedback loop 302 to control the operation of the scanner 296. the cantilever of the present invention is


( reuters ) - scientists at europe ' s cern research centre have found a new subatomic particle, a basic building block of the universe, which appears to be the boson imagined and named half a century ago by theoretical physicist peter higgs. " we have reached a milestone in our understanding of nature, " cern director general rolf heuer told a gathering of scientists and the world ' s media near geneva on wednesday. " the discovery of a particle consistent with the higgs boson opens the way to more detailed studies, requiring larger statistics, which will pin down the new particle ' s properties, and is likely to shed light on other mysteries of our universe. " two independent studies of data produced by smashing proton particles together at cern ' s large hadron collider produced a convergent near - certainty on the existence of the new particle. it is unclear whether it is exactly the boson higgs described. but addressing scientists assembled in the cern auditorium, heuer posed them a question : " as a layman, i would say i think we have it. would you agree? " a roar of applause said they did. for some, there was no doubt the higgs boson is found : " it ' s the higgs, " said jim al - khalili of surrey university, a british physicist and popular broadcaster. " the announcement from cern is even more definitive and clear - cut than most of us expected. " higgs, now 83, from edinburgh university was among six theorists who in the early 1960s proposed the existence of a mechanism by which matter in the universe gained mass. higgs himself argued that if there were an invisible field responsible for the process, it must be made up of particles. he and some of the others were at cern to welcome news of what, to the embarrassment of many scientists, some commentators have labeled the " god particle ", for its role in turning the big bang into a living universe. clearly overwhelmed, his eyes welling up, higgs told the symposium of fellow researchers : " it is an incredible thing that it has happened in my lifetime. " also read more and join the discussion in an article by lawrence krauss on slate that was posted earlier today. note that the discussion thread for both articles is combined.


california internet voting task force technical committee recommendations table of contents activex control : a program packaged in a format designed by microsoft that is downloaded from a web server to a client browser and run within the browser, all as a mere side effect of visiting a web page. applet : a program in sun microsystems ’ java programming language that is downloaded from a web server to a browser and run in the browser as a side effect of visiting a web page. atomic : a multi - step operation is atomic if, whenever it is attempted, it either fails completely, accomplishing nothing at all, or succeeds completely, accomplishing all of the steps, but never stops in an intermediate, partially - completed state. authentication : verification of the true source of a message. in the case of i - voting, this refers to verification that an electronic ballot really is from the person it claims to come from, and not just from someone trying to electronically impersonate that person. biometric : a digitizable characteristic of a person ’ s physiology or behavior that uniquely identifies him or her. examples include thumb print, dna sample, voice print, hand - writing analysis, etc. browser : an application program such as microsoft internet explorer or netscape navigator that allows the user to navigate the world wide web, and interact with pages from it. certification : the process the state uses to determine that a voting system meets the requirements of the california election code and can be used by any county that decides to select it. client : in a common two - computer interaction pattern, one of them, the client, initiates a request, and the other, the server, acts on that request and replies back to the client. in the case of i - voting, " client " refers to the voter ’ s computer that initiates the process of voting, and the server is the computer that accepts the ballot and replies to the client that it accepted it. cryptography : the mathematical theory of secret codes and related security issues. decryption : decoding an encrypted message ( usually using a secret key ). digital signature : cryptographically - generated data block appended to a document to prove the document was processed by the person whose secret key was used to generate the data block. encryption : encoding ( i. e. scrambling ) a message using a secret key so that anyone intercepting the message but not in possession of the key cannot understand it.. failure tolerance : the ability of a system to continue to function in spite of the failure of some of its


e. scrambling ) a message using a secret key so that anyone intercepting the message but not in possession of the key cannot understand it.. failure tolerance : the ability of a system to continue to function in spite of the failure of some of its parts. ecommerce : electronic commerce, i. e. financial transactions conducted over a computer network or the internet. email : electronic mail, i. e. messages and documents sent from one party to other specific, named parties. firewall : one or more computers standing between a network ( " inside " ) and the rest of the internet ( outside ). it intercepts all traffic in both directions, forwarding only the benign part ( where " benignness " may be defined by a complex policy ), thereby protecting the inside from attacks from the outside. html : hypertext markup language, the notation used for formatting text and multimedia content on web pages. http : hypertext transfer protocol, the communication protocol used between web browsers and web servers for transporting web pages through the internet. i - voting : internet voting integrity : protecting data from undetected modification by unauthorized persons, usually through use of a cryptographic hash or digital signature. internet : the worldwide system of separately - owned and administered networks that cooperate to allow digital communication among the world ’ s computers. ip : internet protocol, the basic packet - exchange protocol of the internet. all other internet protocols, including http ( the web ) and smtp ( email ) use it. ip address : a unique number ( address ) assigned to every computer on the internet, including home computers temporarily connected to the internet. isp : internet service provider ; a company whose business is to sell access to the internet, usually through phone lines or catv cable, to homes, businesses, and institutions. key : a typically ( but not always ) secret number that is long enough and random - looking enough to be unguessable ; used for encrypting or decrypting messages. key pair : a pair of keys, one used for encrypting messages and the other for decrypting them. used in public key cryptographic protocols for authentication, digital signatures, and other security purposes. kiosk : a booth - or lectern - like system with a screen, keyboard, and mouse mounted so they are available to users, but with a tamper - proof computer inside and a secure internet connection to the server. mirroring : keeping two or more memory systems or computers identical at all times, so


a screen, keyboard, and mouse mounted so they are available to users, but with a tamper - proof computer inside and a secure internet connection to the server. mirroring : keeping two or more memory systems or computers identical at all times, so that if one fails the other can continue without any disruption of service. lan : local area network ; a short - range ( building - size ) network with a common administration and with a only small number of hosts ( computers ) attached. the hosts are considered to be sufficiently cooperative that only light security precautions are required. malicious code : a program with undesirable behavior that operates secretly or invisibly, or is disguised as part of a larger useful program ; in this document, the same as " trojan horse ". nc : network computer ; a widely - discussed hypothetical product that does not store software or files locally, but works only through a network. online : generally, a synonym for " on the internet ", or sometimes, more specifically, " on the web ". out - of - band communication : communication through some means other than the primary channel under discussion. if the primary communication channel is the internet, then out - of - band channel might be via u. s. mail, or a voice telephone connection, or any other channel that does not involve the internet. packet : the smallest unit of data ( along with overhead bytes ) transmitted over the internet in the ip protocol. pc : personal computer ; any commercial computers marketed to consumers for home or business use by one person at a time. in 1999, this includes intel - based computers ( and clones ) running a microsoft operating system or a competitor ( e. g. linux, beos, etc. ), and it also includes macintoshes. plug - in : a software module that permanently extends the capability of a web browser. privacy : protecting data from being read by unauthorized persons, generally by encrypting it using a secret key. private key : a key, or one member of a key pair, that must be kept secret by one or all members of a group of communicating parties. protocol : an algorithm or program involving two or more communicating computers. public key : one member of a key pair that is made public. public key cryptosystem : a cryptographic protocol involving a pair of keys, one of which is made public and the other held secret. redundancy : excess storage, communication capacity, computational capacity, or data, that allows a task to be accomplished even in the event of some failures


##ographic protocol involving a pair of keys, one of which is made public and the other held secret. redundancy : excess storage, communication capacity, computational capacity, or data, that allows a task to be accomplished even in the event of some failures or data loss. replication : a simple form of redundancy ; duplication, triplication, etc. of resources or data to permit detection of failures or to allow successful completion of a task in spite of failures. security : general term covering issues such as privacy, integrity, authentication, etc. server : in a two - computer interaction pattern, one of them, called the client, initiates a request, and the other, the server, acts on that request and replies to the client. in the case of i - voting the computer that receives and stored the ballots from voters is the server. spoof : to pretend, usually through a network, to be someone or somewhere other than who or where you really are trojan horse : a program with undesirable behavior that operates secretly or invisibly, or is disguised as part of a larger useful program ; in this document, the same as " malicious code ". tunnel : a cryptographic technique in which a computer is in effect attached to a remote lan via the internet, even if there is an intervening firewall. url : uniform resource locator, i. e. a name for a web page, such ashttp : / / vote2000. ss. ca. gov. usb port : universal serial bus port ; a port ( connector ) on newer computers used for high speed serial communication with attached devices. virus : a trojan horse program that actively makes, and covertly distributes, copies of itself. vote client : the computer that voters use to cast their ballots, which are then sent to the vote server. vote server : the computer ( s ) under control of the county that receives and stores votes transmitted by internet from vote clients. web : the world - wide web, or www ; the worldwide multimedia and hypertext system that, along with email, is the most familiar service on the internet. web site : a collection of related web pages, generally all located on the same computer and reachable from a single top - level " home page ". web page : a single " page " of material from a web site.


##t data and makes it available to researchers. astrophysics and particle physics may seem strange bedfellows, but atwood has no trouble explaining how a telescope designer could win an award named after the founding director of a linear accelerator, or how a particle physicist could be enticed to work on a satellite. " almost all light comes from something hot, " he said. in astronomical observing terms, visible light comes from the nuclear fires of the stars. infrared light comes from hot dust and gas. but gamma rays are an exception to this rule. “ stuff can ’ t get hot enough ” to produce photons of light in the gamma - ray range, with energies measured in the millions and billions of electron volts, atwood said. what that means is that gamma rays show us the " non - thermal universe " – in other words, the part of the sky that heat cannot reveal. only extreme conditions can generate gamma rays, atwood said – " black holes and neutron stars, pulsars. the gamma - ray sky is full of these exotic objects. " and these exotic objects provide the extreme conditions necessary to accelerate particles to high energy. at first, atwood said, both the particle physics and the astrophysics communities were skeptical that this telescope was the proper instrument to conduct particle physics research or gamma ray astronomy. " in the end, a good idea is a good idea and people came around, " he said. in fact, " this instrument would not have been possible without the active participation of both communities. "


in this course, we cannot offer a complete study of the logical universal and its implications. we limit ourselves to analyzing briefly the various instances which correspond to the makeup of the universal. a text of st thomas will set us on our way : when one says ‘ a thing which is actually being understood ’ ( intellectum in actu ), there are two things implied, viz., ( a ) the thing which is being understood and ( b ) the fact that it is being understood. similarly, when one says ‘ the abstracted universal ’, there are two things implied, viz., ( a ) the nature itself of the thing and ( b ) its abstractness or universality. therefore, the nature which happens to be understood intellectively ( or to be abstracted or to be an intention of universality ) does not itself exist except in singular things ; but its being understood ( or being abstracted or being an intention of universality ) exists in the intellect. we can see this by a comparison with a sensory power. for the power of sight sees the color of the apple without seeing its smell. therefore, if someone asked where the color is that is seen without the smell, it is obvious that the color which is seen exists only in the apple ; however, the fact that it is perceived without its smell happens to it because of the power of sight, since in the power of sight there exists a likeness of its color but not of its smell. similarly, the human - ness ( humanitas ) that is understood intellectively exists only in this or that man ; but the fact that human - ness is apprehended without individual conditions — i. e., the fact that human - ness is abstracted, and that an intention of universality follows upon it — happens to human - ness insofar as it is perceived by the intellect, in which there is a likeness of the nature of the species without a likeness of the individual principles. i, 85, 2, 2m cum dicitur intellectum in actu, duo importantur : scilicet res quæ intelligitur, et hoc quod est ipsum intelligi. et similiter cum dicitur universale abstractum, duo intelliguntur : scilicet ipsa natura rei, et abstractio seu universalitas. ipsa igitur natura cui accidit vel intelligi vel abstrahi, vel intentio universalitatis, non est nisi in


| 1. | | colloidal solution, also called : colloidal suspension a mixture having particles of one component, with diameters between 10 - - 7 and 10 - - 9 metres, suspended in a continuous phase of another component. the mixture has properties between those of a solution and a fine suspension | | 2. | | the solid suspended phase in such a mixture | | 3. | | obsolete compare crystalloid a substance that in solution does not penetrate a semipermeable membrane | | 4. | | physiol a gelatinous substance of the thyroid follicles that holds the hormonal secretions of the thyroid gland | | 5. | | pathol of or relating to the gluelike translucent material found in certain degenerating tissues | | 6. | | of, denoting, or having the character of a colloid | | [ c19 : from greek kolla glue + | | a children ' s mummer ' s parade, as on the fourth of july, with prizes for the best costumes. | | the offspring of a zebra and a donkey. | colloid col · loid ( kol ' oid ' ) a suspension of finely divided particles in a continuous medium from which the particles do not settle out rapidly and are not readily filtered. the particulate matter so suspended. the gelatinous stored secretion of the thyroid gland, consisting mainly of thyroglobulin. gelatinous material resulting from colloid degeneration in diseased tissue. also called colloidin. | colloid ( kol ' oid ' ) pronunciation key a mixture in which very small particles of one substance are distributed evenly throughout another substance. the particles are generally larger than those in a solution, and smaller than those in a suspension. paints, milk, and fog are colloids. compare solution, suspension. a substance made up of particles that are larger than most molecules ; these particles do not actually dissolve in substances but stay suspended in them. note : fog, paints, and foam rubber are colloids.


- groupe ( obsolete ) from french groupe ( “ cluster, group ” ), from italian gruppo, groppo ( “ a knot, heap, group, bag ( of money ) ” ), from proto - germanic * kruppaz ( “ lump, round mass, body, crop ” ), from proto - indo - european * greub - ( “ to crumple, bend, crawl ” ). cognate with german kropf ( “ crop, craw, bunch ” ), old english cropp, croppa ( “ cluster, bunch, sprout, flower, berry, ear of corn, crop ” ), dutch krop ( “ craw ” ), old norse kroppr ( “ hump, bunch ” ). more at crop, croup. group ( plural groups ) - a number of things or persons being in some relation to one another. - there is a group of houses behind the hill. - a group of people gathered in front of the parliament to demonstrate against the prime minister ' s proposals. - he left town to join a communist group - ( group theory ) a set with an associative binary operation, under which there exists an identity element, and such that each element has an inverse. - a ( usually small ) group of people who perform music together. - did you see the new jazz group? - ( astronomy ) a small number ( up to about fifty ) of galaxies that are near each other. - ( chemistry ) a column in the periodic table of chemical elements. - ( chemistry ) a functional entity consisting of certain atoms whose presence provides a certain property to a molecule, such as the methyl group. - ( sociology ) a subset of a culture or of a society. - ( military ) an air force formation. - ( geology ) a collection of formations or rock strata. - ( computing ) in the unix operating system, a number of users with same rights with respect to accession, modification, and execution of files, computers and peripherals. - an element of an espresso machine from which hot water pours into the portafilter. - ( number of things or persons being in some relation to each other ) : collection, set - ( people who perform music together ) : band, ensemble - see also wikisaurus : group - ( in group theory ) : monoid - ( put together to form a group ) : amass, categorise / categorize, classify, collect


more and more wimps thermalize inside the sun, they begin to annihilate with each other, forming a variety of particles including high - energy neutrinos. these neutrinos may then travel to the earth to be detected in one of the many neutrino telescopes, such as the super - kamiokande detector in japan. the number of neutrino events detected per day at these detectors depends upon the properties of the wimp, as well as on the mass of the higgs boson. similar experiments are underway to detect neutrinos from wimp annihilations within the earth and from within the galactic center. while most wimp models indicate that a large enough number of wimps must be captured in large celestial bodies for these experiments to succeed, it remains possible that these models are either incorrect or only explain part of the dark matter phenomenon. thus, even with the multiple experiments dedicated to providing indirect evidence for the existence of cold dark matter, direct detection measurements are also necessary to solidify the theory of wimps. although most wimps encountering the sun or the earth are expected to pass through without any effect, it is hoped that a large number of dark matter wimps crossing a sufficiently large detector will interact often enough to be seen — at least a few events per year. the general strategy of current attempts to detect wimps is to find very sensitive systems that can be scaled up to large volumes. this follows the lessons learned from the history of the discovery and ( by now ) routine detection of the neutrino. a technique used by the cryogenic dark matter search ( cdms ) detector at the soudan mine relies on multiple very cold germanium and silicon crystals. the crystals ( each about the size of a hockey puck ) are cooled to about 50 mk. a layer of metal ( aluminium and tungsten ) at the surfaces is used to detect a wimp passing through the crystal. this design hopes to detect vibrations in the crystal matrix generated by an atom being " kicked " by a wimp. the tungsten metal sensors are held at the critical temperature so they are in the superconducting state. large crystal vibrations will generate heat in the metal and are detectable because of a change in resistance. in february 2010, researchers at the soudan mine cdms ii experiment announced that they had observed two events that may have been caused by wimp - nucleus collisions. cogent, a smaller detector using a single germanium puck, designed to sense wimps with


. however, the problem to contend with in darwinian co - evolution is the possibility of an escalating arms race with no end. competing species may continually adapt to each other in more and more specialized ways, never stabilizing at a desirable outcome. the rock - scissors - paper ( rsp ) game is a typical form of representing the triangular relationship. this simple game has been used to explain the importance of biodiversity. we generalize a basic rock - scissors - paper relationship to a non - zero - sum game with the payoff matrix shown in table 1. in this triangular situation, diversity resulting from proper dispersal by achieving nash equilibrium is not efficient, and the agents may benefit from achieving a better relationship. in particular, we have examined the system of interactive evolving agents in the context of repeated rsp games, by considering a population of agents located on a lattice network of 20x20. they repeatedly play the generalized rsp game with their nearest eight neighbours based on the coupling rules, which are updated by the crossover operator. 400 different rules, one for each agent, are aggregated at the beginning into a few rules with many commonalities. the game between two agents with the learned coupling rule becomes a kind of stochastic process. the transitions of the outcome are represented as the phase diagram in figure 1, and they converge into the limit cycle, visiting the pareto - optimal outcomes : ( 0, 1 ) ( 1, 2 ) ( 2, 0 ) ( 1, 0 ) ( 2, 1 ) ( 0, 2 ). therefore each agent learns to behave as follows : win three times and then lose three times. in this way, the agents succeed in collectively evolving a robust learning procedure that leads to near - optimal behaviour based on the principle of give and take. the framework of collective evolution is distinguished from co - evolution in three aspects. first, there is the coupling rule : a deterministic process that links past outcomes with future behaviour. the second aspect, which is distinguished from individual learning, is that agents may wish to optimize the outcome of the joint actions. the third aspect is to describe how a coupling rule should be improved, using the criterion of performance to evaluate the rule. in biology, the gene is the unit of selection. however, the collective evolutionary process is expected to compel agents towards ever more refined adaptation, resulting in sophisticated behavioural rules. cultural interpretations of collective evolution assume that successful behavioural rules are spread by imitation or learning by the agents. this approach to collective evolution is


maglev ( transport ) information maglev ( derived from magnetic levitation ) is a system of transportation that uses magnetic levitation to suspend, guide and propel vehicles with magnets rather than using mechanical methods, such as wheels, axles and bearings. with maglev a vehicle is levitated a short distance away from a guideway using magnets to create both lift and thrust. high - speed maglev train solutions promise dramatic improvements for human travel if widespread adoption occurs. maglev trains work with an electro magnet, maglev trains move more smoothly and somewhat more quietly than wheeled mass transit systems. their non - reliance on friction means that acceleration and deceleration can surpass that of wheeled transports, and they are unaffected by weather. the power needed for levitation is typically not a large percentage of the overall energy consumption ; most of the power is used to overcome air resistance ( drag ), as with any other high - speed form of transport. although conventional wheeled transportation can go very fast, maglev allows routine use of higher top speeds than conventional rail, and this type holds the speed record for rail transportation. vacuum tube train systems might hypothetically allow maglev trains to attain speeds in a different order of magnitude, but no such tracks have ever been built. compared to conventional wheeled trains differences in construction affect the economics. with wheeled trains, at very high speeds, the wear and tear from friction along with the concentrated pounding from wheels on rails accelerate equipment deterioration and prevent mechanically - based train systems from routinely achieving higher speeds. conversely, maglev tracks have historically been found to be much more expensive to construct, but require less maintenance and have low ongoing costs. despite decades - long research and development, there are presently only two commercial maglev transport systems in operation, with two others under construction. in april 2004, shanghai began commercial operations of the high - speed transrapid system. in march 2005, japan began operation of the relatively low - speed hsst " linimo " line in time for the 2005 world expo. in its first three months, the linimo line carried over 10 million passengers. south korea and the people ' s republic of china are both building low - speed maglev lines of their own design, one in beijing and the other at seoul ' s incheon airport. many maglev projects are controversial, and the technological potential, adoption prospects and economics of maglev systems have often been hotly debated. the shanghai system has been accused of being a white elephant. high - speed transportation patents were granted to various inventors throughout the


the train attract it to a magnetically conductive ( usually steel ) track. - electrodynamic suspension ( eds ) uses superconducting electromagnets or strong permanent magnets which create a magnetic field that induces currents in nearby metallic conductors when there is relative movement which pushes and pulls the train towards the designed levitation position on the guide way. another experimental technology, which was designed, proven mathematically, peer reviewed, and patented, but is yet to be built, is the magnetodynamic suspension ( mds ), which uses the attractive magnetic force of a permanent magnet array near a steel track to lift the train and hold it in place. other technologies such as repulsive permanent magnets and superconducting magnets have seen some research. electromagnetic suspensionmain article : electromagnetic suspension in current electromagnetic suspension ( ems ) systems, the train levitates above a steel rail while electromagnets, attached to the train, are oriented toward the rail from below. the system is typically arranged on a series of c - shaped arms, with the upper portion of the arm attached to the vehicle, and the lower inside edge containing the magnets. the rail is situated between the upper and lower edges. magnetic attraction varies inversely with the cube of distance, so minor changes in distance between the magnets and the rail produce greatly varying forces. these changes in force are dynamically unstable – if there is a slight divergence from the optimum position, the tendency will be to exacerbate this, and complex systems of feedback control are required to maintain a train at a constant distance from the track, ( approximately 15 millimeters ( 0. 59 in ) ). the major advantage to suspended maglev systems is that they work at all speeds, unlike electrodynamic systems which only work at a minimum speed of about 30 km / h ( 19 mph ). this eliminates the need for a separate low - speed suspension system, and can simplify the track layout as a result. on the downside, the dynamic instability of the system demands high tolerances of the track, which can offset, or eliminate this advantage. laithwaite, highly skeptical of the concept, was concerned that in order to make a track with the required tolerances, the gap between the magnets and rail would have to be increased to the point where the magnets would be unreasonably large. in practice, this problem was addressed through increased performance of the feedback systems, which allow the system to run with close tolerance


zinc oxide ( zno ) is considered a workhorse of technological development exhibiting excellent electrical, optical, and chemical properties with a broad range of applications as semiconductors, in optical devices, piezoelectric devices, surface acoustic wave devices, sensors, transparent electrodes, solar cells, antibacterial activity etc. thin films or nanoscale coating of zno nanoparticles on suitable substrates are viewed with great interest for their potential applications as substrates for functional coating, printing, uv inks, e - print, optical communication ( security - papers ), protection, barriers, portable energy, sensors, photocatalytic wallpaper with antibacterial activity etc. various methods like chemical, thermal, spin coating, spray pyrolysis, pulsed laser deposition have been used for thin film formation but they are limited to solid supports such as metal, metal oxides, glass or other thermally stable substrates. coating of zno nanoparticles on thermolabile surfaces is scarce and coating on paper was yet to be reported. paper as a substrate is an economic alternative for technological applications having desired portability and flexibility. researchers from the national tsing hua university in taiwan found a way of coating paper with zno nanoparticles using ultrasound. with the advent of nanoscience and technology, a new area has developed in the area of textile finishing called " nanofinishing ". growing awareness of health and hygiene has increased the demand for bioactive or antimicrobial and uv - protecting textiles. coating the surface of textiles and clothing with nanoparticles is an approach to the production of highly active surfaces to have uv blocking, antimicrobial, flame retardant, water repellant and self - cleaning properties. while antimicrobial properties are exerted by nano - silver, uv blocking, self - cleaning and flame - retardant properties are imparted by nano - metal oxide coatings. zinc oxide ( zno ) nanoparticles embedded in polymer matrices like soluble starch are a good example of functional nanostructures with potential for applications such as uv - protection ability in textiles and sunscreens, and antibacterial finishes in medical textiles and inner wears. the discussion about the health scare caused by the magic - nano sealing spray ( which, as it turned out, was neither magic nor nano - see this article ) has barely ebbed when questions about another nano consumer product arise. this time, it is not a health scare but rather the opposite -