accessmylibrary provides free access to millions of articles from top publications available through your library. criticizing the standard ( neoclassical ) optimization model in economics, several years ago herbert simon ( 1978 ) argued that : in the past economics has largely ignored the process that rational man uses in reaching his resource allocation. this was possibly an acceptable strategy for explaining rational decision in static, relatively simple problem situations where it might be assumed that additional computational time or power could not change the outcome. the strategy does not work, however, when we are seeking to explain the decision maker ' s behavior in complex, dynamic circumstances that involve a great deal of uncertainty, and that make demands upon his attention. ( p. 14 ) simon then urges economists to give an account of substantive rationality, as well as procedural rationality in light of human cognitive powers and limitations. while conventional theory assumes that economic agents respond to information perfectly in the sense of always making decisions that maximize expected utility based on their observed information, opponents of the neoclassical optimization theory have argued that real world agents have severe limitations in their ability to process information, which thereby prevents them from perfectly using information without error ( heiner, 1988 ). the difficulty that conventional economics has faced in studying the actual behavior of economic agents has been the assumption that any behavior which is not fully rational must be random and not subject to scientific research ( akerlof & dickens, 1982 ). for example, gary becker ( 1962 ) has viewed irrational behavior as random deviations from economic rationality, and thus not subject to scientific investigation. however, recent developments in psychology and other behavioral sciences suggest the existence of a continuum of qualitatively distinct states of partial rationality, or systematic irrationality. these writers have found irrational behavior as predictable, and therefore not totally random. this body of research deals essentially with cognitive dissonance, a psychological concept first discussed by leon festinger in 1957. since 1957, various psychologists and other behavioral scientists have discussed cognitive dissonance and its impact on the processing of available information. it will be demonstrated that these theorists have identified a wide range of cognitive processes which serve to simplify decision maker ' s perceptions of problems. since 1965, when albert hirschman applied the concept to attitudes toward modernization, various economists have applied cognitive dissonance to economic behavior. in general, a growing number of researchers aim at a better understanding of human action in the face of uncertainty. simon ' s concept of satisficing and schelling ' s notion of pre - commitment and self control are among alternatives


june 21, 2010 for immediate release a crack in the case for supersolids reports of supersolid helium may have been premature physicists have long known that helium can become a superfluid at low temperatures, allowing it to flow completely friction free, spontaneously climb walls, and exhibit other counterintuitive characteristics. based on quantum mechanical calculations dating back to the 1970 ' s, some physicists predicted similar effects in solid materials. in particular, they expected ultracold solid helium could become a mixture of normal solid and supersolid forms. it wasn ' t until 2004 that physicists were able to devise a way to look for supersolid behavior in helium. they filled a hollow torsion pendulum ( a type of pendulum that rotates rather than swinging back and forth ) with helium, then measured the rate that it twisted as the helium was cooled. because the periodic twisting rate depends in part on the amount of normal helium in the pendulum cavity, they expected that the period would change if some of the helium became supersolid. when researchers found the period change they were expecting, many physicists declared the hunt for supersolid helium had finally come to an end. according to reppy ' s experiments, which are the subject of a viewpoint by john beamish ( university of alberta ) in the latest edition of aps physics ( http : / / physics. aps. org ), the period change may have had nothing to do with supersolids at all. instead, it ' s possible that the normal helium was deforming as the pendulum twisted. the conclusion is the result of a new pendulum design and methods to control the structure of the solid helium inside, which should allow physicists to tease out the effects of supersolid helium from the effects of deformations. it ' s not yet clear that observations of supersolid helium were in error. even if that ' s the case, the possibility that deformations are responsible for the period change in a helium - filled pendulum is nearly as intriguing to physicists as supersolid helium because it may result from a poorly understood phenomenon known as quantum plasticity. only further research will determine whether supersolidity or quantum plasticity is responsible for the odd behavior of super - cold, solid helium. the american physical society ( www. aps. org ) is a non - profit membership organization working to advance and diffuse the knowledge of physics through its outstanding research journals, scientific meetings, and education, outreach, advocacy and international activities. aps represents over 50,


terms that are on use on this site. there are 493 entries in this glossary. symbolic representation illustrates schematically the functions of a control circuit. the power lines form the sides of a ladder - like structure, with the program elements arranged to form the rungs. local area network. a network that takes advantage of the proximity of computers to offer relatively efficient, higher - speed communications than long - haul or wide - area networks. link access protocol. light - emitting diodes are solid - state devices that radiate in the visible region. they are used in alphanumeric displays and as indicator or wiring lights. the minimum number of pressure cycles the transducer can endure and still remain within a specified tolerance. an electromechanical device positioned to be actuated when a certain motion limit occurs, thereby deactivating the actuator causing the motion. | limits of error | | a tolerance band for the thermal electric response of thermocouple wire expressed in degrees or percentage defined by ansi specification mc - 96. 1 ( 1975 ). said of any device or motion where the effect is exactly proportional to the cause. a predictable nonprocess energy load that has a profile that changes with time and condition. a management technique applied to problems in which a linear function of a number of variables is subject to a number of constraints in the form of linear inequalities. developed as a technique for planning the diversified activities of the u. s. air force, the process generates several different plans, requiring a criterion for deciding which plan is best and how to find it. mathematically, linear programming is the analysis of problems in which a linear function of a number of variables is to be maximized or minimized when those variables are subject to a number of restraints in the form of linear inequalities. the maximum deviation of the calibration curve from a straight line between zero and full scale, expressed as a percent of full scale output and measured on increasing measured only. a transducer for the measurement of force or weight. action is based on strain gages mounted within the cell on a force beam. maximum rate at which a control loop can respond to a change in a control parameter. it ' s indicative of loop performance and is expressed in hertz ( hz ). the total resistance of a thermocouple circuit caused by the resistance of the thermocouple wire. usually used in reference to analog pyrometers which have typical loop resistance requirements of 10


a glossary of speaker materials click on a letter below to jump to that section of the glossary. | don ' t know the difference between " aramid " and " titanium "? this glossary lists many of the materials used by speaker manufacturers. use this guide to get a better understanding of the materials in a speaker and how they will perform. | polypropylene coated with a thin layer of aluminum. the combination creates a stiff, lightweight material used in woofer cones. a synthetic fiber with excellent strength - to - weight properties. it can be woven into a fabric, or blended into polypropylene to produce lightweight, weather - resistant woofer cones that have the natural sound characteristics found in high - quality paper cones. a rubber / butylene compound with excellent flexibility and durability. used for speaker surrounds. cast metals have a greater resistance to resonance than stamped metals when used in speaker baskets. cast aluminum combines light weight with rigidity and strength. c. m. m. d. ( ceramic metal matrix diaphragm ) first developed by infinity for their home speakers, c. m. m. d. is a layered composite of thin ceramics and metal. this material is non - resonant, stiff and quite strong. it is notable for producing uncolored sound with excellent dispersion. c. m. m. d. is used for woofers, midranges and tweeters. ferrofluids dissipate heat that builds up in speaker voice coils. since ferrofluids are magnetic, they don ' t require physical containment — the speaker ' s magnetic field holds the fluid in place. when polypropylene is injected as a foam into a speaker mold, the resulting material retains air bubbles that make it lighter without giving up strength. a blend of glass fibers and plastics with excellent heat resistance. used in constructing voice coil formers. a composite material of polypropylene and graphite that is stiffer and stronger than regular polypropylene film. hcl ( honeycomb - laminate ) is a laminate that combines layers of woven glass fiber with an inner core of nomex honeycomb. the result is a very strong material, excellent for speakers that need to handle high power. h. o. p. ( highly oriented polyolefine ) the molecules in highly oriented polyolefine are arranged in linear strands, giving this material more inherent strength and rigidity than most other polymer films. h. o. p.


in cell biology, a mitochondrion ( plural mitochondria ) ( from greek mitos thread + khondrion granule ) is an organelle, variants of which are found in most eukaryotic cells. mitochondria are sometimes described as " cellular power plants, " because their primary function is to convert organic materials into energy in the form of atp via the process of oxidative phosphorylation. usually a cell has hundreds or thousands of mitochondria, which can occupy up to 25 % of the cell ' s cytoplasm. mitochondria usually have their own dna ( mtdna ) ; according to the generally accepted endosymbiotic theory, they were originally derived from external organisms. a mitochondrion contains outer and inner membranes composed of phospholipid bilayers studded with proteins, much like a typical cell membrane. the two membranes, however, have very different properties. the outer mitochondrial membrane, which encloses the entire organelle, contains numerous integral proteins called porins, which contain a relatively large internal channel ( about 2 - 3 nm ) that is permeable to all molecules of 5000 daltons or less [ alberts, 1994 ]. larger molecules can only tranverse the outer membrane by active transport. the outer mitochondrial membrane is composed of about 50 % phospholipids by weight and contains a variety of enzymes involved in such diverse activities as the elongation of fatty acids, oxidation of epinephrine ( adrenaline ), and the degradation of tryptophan. the inner membrane contains proteins with three types of functions [ alberts, 1994 ] : - those that carry out the oxidation reactions of the respiratory chain - atp synthase, which makes atp in the matrix - specific transport proteins that regulate the passage of metabolites into and out of the matrix. it contains more than 100 different polypeptides, and has a very high protein - to - phospholipid ratio ( more than 3 : 1 by weight, which is about 1 protein for 15 phospholipids ). additionally, the inner membrane is rich in an unusual phospholipid, cardiolipin, which is usually characteristic of bacterial plasma membranes. unlike the outer membrane, the inner membrane does not contain porins, and is highly - impermeable ; almost all ions and molecules require special membrane transporters to enter or exit the matrix. the mitochondrial matrix the matrix is the space enclosed


secondary is driven by matter pressure, not radiation pressure. incidentally, dow chemical complained that styrofoam is a trademark, like xerox, and that nuclear weapons do not contain styrofoam. point conceded ; the foam is generic. plasma physics, the study of ionized gases, has the same cachet in popular culture as rocket science - - the exclusive purview of geniuses, usually ones with security clearances. it is certainly legitimate science. plasma is the most common state of matter in the universe : hot, dense plasma inside stars and cold, diffuse plasma in interstellar space. but if the full story of plasma physics is ever told, i wager that an inordinate portion of the field will turn out to concern the behavior of x - ray heated plastic, or similar material, in the radiation channels of exploding h - bombs. the need for mathematical simulations of this process was a key factor driving the early development of electronic computers. i like the idea of a nuisance material, plastic foam, as the real secret of the h - bomb. it symbolizes the banality of evil which is the essence of the whole h - bomb business. workaday people doing workaday jobs building doomsday machines based on 1950 ' s technology, while civilization marches bravely into the new millennium, oblivious to the death sentence imposed by a secret technology involving plastic foam. it calls to mind the most famous line from the graduate, " one word : plastics. " within the small community of researchers and authors who study this arcane subject from the outside, there is still no consensus about the precise role of plastic channel filler in radiation implosion. it is agreed that the plastic absorbs energy and is heated to plasma temperatures, and that radiation " flows " through the resulting plasma at orders of magnitude slower than the speed of light in a vacuum. it is also agreed that radiation implosion operates on temperature difference. the interior of the secondary is cold compared with the heated environment around it. the hot stuff expands and crushes the cold stuff. whether the hot plastic does the pushing or transmits its heat to a designated ablator which does the pushing a matter of continuing discussion. anyway, i got two and a half out of three concepts right, which was evidently a passing grade in terms of triggering censorship. my original explanation still added up to radiation implosion, which was the unspeakable idea. technically, according to the " born secret " clause of the atomic energy act,