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41 Chapelon, André
[br]b. 26 October 1892 Saint-Paul-en-Cornillon, Loire, Franced. 29 June 1978 Paris, France[br]French locomotive engineer who developed high-performance steam locomotives.[br]Chapelon's technical education at the Ecole Centrale des Arts et Manufactures, Paris, was interrupted by extended military service during the First World War. From experience of observing artillery from the basket of a captive balloon, he developed a method of artillery fire control which was more accurate than that in use and which was adopted by the French army.In 1925 he joined the motive-power and rolling-stock department of the Paris-Orléans Railway under Chief Mechanical Engineer Maurice Lacoin and was given the task of improving the performance of its main-line 4–6–2 locomotives, most of them compounds. He had already made an intensive study of steam locomotive design and in 1926 introduced his Kylchap exhaust system, based in part on the earlier work of the Finnish engineer Kyläla. Chapelon improved the entrainment of the hot gases in the smokebox by the exhaust steam and so minimized back pressure in the cylinders, increasing the power of a locomotive substantially. He also greatly increased the cross-sectional area of steam passages, used poppet valves instead of piston valves and increased superheating of steam. PO (Paris-Orléans) 4–6–2s rebuilt on these principles from 1929 onwards proved able to haul 800-ton trains, in place of the previous 500-ton trains, and to do so to accelerated schedules with reduced coal consumption. Commencing in 1932, some were converted, at the time of rebuilding, into 4–8–0s to increase adhesive weight for hauling heavy trains over the steeply graded Paris-Toulouse line.Chapelon's principles were quickly adopted on other French railways and elsewhere.H.N. Gresley was particularly influenced by them. After formation of the French National Railways (SNCF) in 1938, Chapelon produced in 1941 a prototype rebuilt PO 2–10–0 freight locomotive as a six-cylinder compound, with four low-pressure cylinders to maximize expansive use of steam and with all cylinders steam-jacketed to minimize heat loss by condensation and radiation. War conditions delayed extended testing until 1948–52. Meanwhile Chapelon had, by rebuilding, produced in 1946 a high-powered, three-cylinder, compound 4–8–4 intended as a stage in development of a proposed range of powerful and thermally efficient steam locomotives for the postwar SNCF: a high-speed 4–6–4 in this range was to run at sustained speeds of 125 mph (200 km/h). However, plans for improved steam locomotives were then overtaken in France by electriflcation and dieselization, though the performance of the 4–8–4, which produced 4,000 hp (3,000 kW) at the drawbar for the first time in Europe, prompted modification of electric locomotives, already on order, to increase their power.Chapelon retired from the SNCF in 1953, but continued to act as a consultant. His principles were incorporated into steam locomotives built in France for export to South America, and even after the energy crisis of 1973 he was consulted on projects to build improved, high-powered steam locomotives for countries with reserves of cheap coal. The eventual fall in oil prices brought these to an end.[br]Bibliography1938, La Locomotive à vapeur, Paris: J.B.Bailière (a comprehensive summary of contemporary knowledge of every function of the locomotive).Further ReadingH.C.B.Rogers, 1972, Chapelon, Genius of French Steam, Shepperton: Ian Allan.1986, "André Chapelon, locomotive engineer: a survey of his work", Transactions of the Newcomen Society 58 (a symposium on Chapelon's work).Obituary, 1978, Railway Engineer (September/October) (makes reference to the technical significance of Chapelon's work).PJGR -
42 Intelligence
There is no mystery about it: the child who is familiar with books, ideas, conversation-the ways and means of the intellectual life-before he begins school, indeed, before he begins consciously to think, has a marked advantage. He is at home in the House of intellect just as the stableboy is at home among horses, or the child of actors on the stage. (Barzun, 1959, p. 142)It is... no exaggeration to say that sensory-motor intelligence is limited to desiring success or practical adaptation, whereas the function of verbal or conceptual thought is to know and state truth. (Piaget, 1954, p. 359)ntelligence has two parts, which we shall call the epistemological and the heuristic. The epistemological part is the representation of the world in such a form that the solution of problems follows from the facts expressed in the representation. The heuristic part is the mechanism that on the basis of the information solves the problem and decides what to do. (McCarthy & Hayes, 1969, p. 466)Many scientists implicitly assume that, among all animals, the behavior and intelligence of nonhuman primates are most like our own. Nonhuman primates have relatively larger brains and proportionally more neocortex than other species... and it now seems likely that humans, chimpanzees, and gorillas shared a common ancestor as recently as 5 to 7 million years ago.... This assumption about the unique status of primate intelligence is, however, just that: an assumption. The relations between intelligence and measures of brain size is poorly understood, and evolutionary affinity does not always ensure behavioral similarity. Moreover, the view that nonhuman primates are the animals most like ourselves coexists uneasily in our minds with the equally pervasive view that primates differ fundamentally from us because they lack language; lacking language, they also lack many of the capacities necessary for reasoning and abstract thought. (Cheney & Seyfarth, 1990, p. 4)Few constructs are asked to serve as many functions in psychology as is the construct of human intelligence.... Consider four of the main functions addressed in theory and research on intelligence, and how they differ from one another.1. Biological. This type of account looks at biological processes. To qualify as a useful biological construct, intelligence should be a biochemical or biophysical process or at least somehow a resultant of biochemical or biophysical processes.2. Cognitive approaches. This type of account looks at molar cognitive representations and processes. To qualify as a useful mental construct, intelligence should be specifiable as a set of mental representations and processes that are identifiable through experimental, mathematical, or computational means.3. Contextual approaches. To qualify as a useful contextual construct, intelligence should be a source of individual differences in accomplishments in "real-world" performances. It is not enough just to account for performance in the laboratory. On [sic] the contextual view, what a person does in the lab may not even remotely resemble what the person would do outside it. Moreover, different cultures may have different conceptions of intelligence, which affect what would count as intelligent in one cultural context versus another.4. Systems approaches. Systems approaches attempt to understand intelligence through the interaction of cognition with context. They attempt to establish a link between the two levels of analysis, and to analyze what forms this link takes. (Sternberg, 1994, pp. 263-264)High but not the highest intelligence, combined with the greatest degrees of persistence, will achieve greater eminence than the highest degree of intelligence with somewhat less persistence. (Cox, 1926, p. 187)There are no definitive criteria of intelligence, just as there are none for chairness; it is a fuzzy-edged concept to which many features are relevant. Two people may both be quite intelligent and yet have very few traits in common-they resemble the prototype along different dimensions.... [Intelligence] is a resemblance between two individuals, one real and the other prototypical. (Neisser, 1979, p. 185)Given the complementary strengths and weaknesses of the differential and information-processing approaches, it should be possible, at least in theory, to synthesise an approach that would capitalise upon the strength of each approach, and thereby share the weakness of neither. (Sternberg, 1977, p. 65)Historical dictionary of quotations in cognitive science > Intelligence
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43 Memory
To what extent can we lump together what goes on when you try to recall: (1) your name; (2) how you kick a football; and (3) the present location of your car keys? If we use introspective evidence as a guide, the first seems an immediate automatic response. The second may require constructive internal replay prior to our being able to produce a verbal description. The third... quite likely involves complex operational responses under the control of some general strategy system. Is any unitary search process, with a single set of characteristics and inputoutput relations, likely to cover all these cases? (Reitman, 1970, p. 485)[Semantic memory] Is a mental thesaurus, organized knowledge a person possesses about words and other verbal symbols, their meanings and referents, about relations among them, and about rules, formulas, and algorithms for the manipulation of these symbols, concepts, and relations. Semantic memory does not register perceptible properties of inputs, but rather cognitive referents of input signals. (Tulving, 1972, p. 386)The mnemonic code, far from being fixed and unchangeable, is structured and restructured along with general development. Such a restructuring of the code takes place in close dependence on the schemes of intelligence. The clearest indication of this is the observation of different types of memory organisation in accordance with the age level of a child so that a longer interval of retention without any new presentation, far from causing a deterioration of memory, may actually improve it. (Piaget & Inhelder, 1973, p. 36)4) The Logic of Some Memory Theorization Is of Dubious Worth in the History of PsychologyIf a cue was effective in memory retrieval, then one could infer it was encoded; if a cue was not effective, then it was not encoded. The logic of this theorization is "heads I win, tails you lose" and is of dubious worth in the history of psychology. We might ask how long scientists will puzzle over questions with no answers. (Solso, 1974, p. 28)We have iconic, echoic, active, working, acoustic, articulatory, primary, secondary, episodic, semantic, short-term, intermediate-term, and longterm memories, and these memories contain tags, traces, images, attributes, markers, concepts, cognitive maps, natural-language mediators, kernel sentences, relational rules, nodes, associations, propositions, higher-order memory units, and features. (Eysenck, 1977, p. 4)The problem with the memory metaphor is that storage and retrieval of traces only deals [ sic] with old, previously articulated information. Memory traces can perhaps provide a basis for dealing with the "sameness" of the present experience with previous experiences, but the memory metaphor has no mechanisms for dealing with novel information. (Bransford, McCarrell, Franks & Nitsch, 1977, p. 434)7) The Results of a Hundred Years of the Psychological Study of Memory Are Somewhat DiscouragingThe results of a hundred years of the psychological study of memory are somewhat discouraging. We have established firm empirical generalisations, but most of them are so obvious that every ten-year-old knows them anyway. We have made discoveries, but they are only marginally about memory; in many cases we don't know what to do with them, and wear them out with endless experimental variations. We have an intellectually impressive group of theories, but history offers little confidence that they will provide any meaningful insight into natural behavior. (Neisser, 1978, pp. 12-13)A schema, then is a data structure for representing the generic concepts stored in memory. There are schemata representing our knowledge about all concepts; those underlying objects, situations, events, sequences of events, actions and sequences of actions. A schema contains, as part of its specification, the network of interrelations that is believed to normally hold among the constituents of the concept in question. A schema theory embodies a prototype theory of meaning. That is, inasmuch as a schema underlying a concept stored in memory corresponds to the mean ing of that concept, meanings are encoded in terms of the typical or normal situations or events that instantiate that concept. (Rumelhart, 1980, p. 34)Memory appears to be constrained by a structure, a "syntax," perhaps at quite a low level, but it is free to be variable, deviant, even erratic at a higher level....Like the information system of language, memory can be explained in part by the abstract rules which underlie it, but only in part. The rules provide a basic competence, but they do not fully determine performance. (Campbell, 1982, pp. 228, 229)When people think about the mind, they often liken it to a physical space, with memories and ideas as objects contained within that space. Thus, we speak of ideas being in the dark corners or dim recesses of our minds, and of holding ideas in mind. Ideas may be in the front or back of our minds, or they may be difficult to grasp. With respect to the processes involved in memory, we talk about storing memories, of searching or looking for lost memories, and sometimes of finding them. An examination of common parlance, therefore, suggests that there is general adherence to what might be called the spatial metaphor. The basic assumptions of this metaphor are that memories are treated as objects stored in specific locations within the mind, and the retrieval process involves a search through the mind in order to find specific memories....However, while the spatial metaphor has shown extraordinary longevity, there have been some interesting changes over time in the precise form of analogy used. In particular, technological advances have influenced theoretical conceptualisations.... The original Greek analogies were based on wax tablets and aviaries; these were superseded by analogies involving switchboards, gramophones, tape recorders, libraries, conveyor belts, and underground maps. Most recently, the workings of human memory have been compared to computer functioning... and it has been suggested that the various memory stores found in computers have their counterparts in the human memory system. (Eysenck, 1984, pp. 79-80)Primary memory [as proposed by William James] relates to information that remains in consciousness after it has been perceived, and thus forms part of the psychological present, whereas secondary memory contains information about events that have left consciousness, and are therefore part of the psychological past. (Eysenck, 1984, p. 86)Once psychologists began to study long-term memory per se, they realized it may be divided into two main categories.... Semantic memories have to do with our general knowledge about the working of the world. We know what cars do, what stoves do, what the laws of gravity are, and so on. Episodic memories are largely events that took place at a time and place in our personal history. Remembering specific events about our own actions, about our family, and about our individual past falls into this category. With amnesia or in aging, what dims... is our personal episodic memories, save for those that are especially dear or painful to us. Our knowledge of how the world works remains pretty much intact. (Gazzaniga, 1988, p. 42)The nature of memory... provides a natural starting point for an analysis of thinking. Memory is the repository of many of the beliefs and representations that enter into thinking, and the retrievability of these representations can limit the quality of our thought. (Smith, 1990, p. 1)Historical dictionary of quotations in cognitive science > Memory
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