1,048 research outputs found

    The Recent Study of Thin Brick Pavements by the U.S. Bureau of Public Roads

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    The manufacture of airtight leather gaskets

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    Wherever gaskets are used in conjunction with any type of mechanism operated by compressed air, of course, it is essential that the gaskets be air tight. Whereas it is possible to use rubberized fabric for this purpose with a degree of satisfaction, treated leather has certain advantages which make its use preferable. Leather is readily available and can be cut and molded into various shapes with less difficulty than is encountered in fabricating similar designs from reinforced rubber. Then, too, leather withstands wear much better than rubberized fabric. The problem then arises to treat leather to make it airtight, for leather as we ordinarily know it is a very porous material. The treatment must also water proof the leather since it lasts much longer if it is not affected by water. Gaskets in certain types of mechanisms, such as railway car airbrakes, are subject to temperatures ranging from 120ºF. down to -30ºF. and sometimes lower. The ideal leather treatment must be such that it will not cause the gaskets to become stiff at cold temperatures nor melt and be forced out in hot weather --Reasons for Investigating this Field, pages 1-2

    Проект парогазовой ТЭЦ с противодавленческими турбинами

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    Дипломный проект 86страниц, 5рисунков, 10таблиц, 10 источников, 1 приложение, 7 листов графического материала, ТЕПЛОВАЯ СХЕМА, ПАРОГАЗОВАЯ УСТАНОВКА, КОТЕЛ-УТИЛИЗАТОР, ПАРОВАЯ ТУРБИНА СХЕМА КИП и А. Объектом исследования является парогазовый энергоблок. Цель работы – проект парогазового энергоблока. В процессе работы выполнен расчет тепловой схемы расчетный для проектирования отопления режим. режим, проектирование котла-утилизатора, технико-экономические расчеты. В результате выполнения работы показаны преимущества парогазового энергоблока на базе высокотемпературной газотурбинной установки SGT-800, проект позволяет повысить КПД энергоблока в сравнении с традиционными паросиловыми установками. Технико-экономические расчеты показали быструю окупаемость проекта и низкую себестоимость электроэнергии. Пояснительная записка выполнена в текстовом редакторе Microsoft Of- fice Word 2007, чертежи в графических редакторах Компас.Graduation project 86stranits, 5risunkov, 10tablits 10 sources 1 annex, 7 sheets of graphic material, Thermal circuit, combined cycle gas turbine, heat recovery boiler, steam turbine and instrumentation A. SCHEME The object of the research is combined-cycle unit. Objective - combined cycle power project. In the process, calculated the thermal circuit current mode for heating design. mode, design recovery boiler, technical and economic calculations. As a result of the work shows the benefits of combined cycle gas turbine power on the basis of high-temperature gas turbine SGT-800 installation, the project improves the power efficiency compared to conventional steam power plants. Technical and economic calculations have shown a rapid return on the project and the low cost of electricity. The explanatory note is made in the text editor Microsoft Of- fice Word 2007 drawing in the graphic editors Compass

    The effect of ambient scent on consumers' perception, emotions, and behaviour: A critical review

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    The effect of olfactory stimuli on consumer behaviour has received little attention in marketing and retailing literature compared to other atmospheric cues. Researchers report ambiguous findings and shortcomings of measurement approaches. Based on a critical literature review, a field experiment in a regional shopping mall investigates the effectiveness of ambient scent. Before-and-after surveys of randomly-selected shoppers in experimental and control groups were conducted and different experimental designs simulated. Those designs not controlling either extraneous variables or attitudinal differences between control and experimental group reveal a positive effect on factors operationalising mall perception and consumers’ emotions. The design controlling both sources of bias indicates no impact of ambient scent on the dependent variables. None of the behavioural variables were affected in any case. This paper questions prior findings on the effectiveness of ambient scent in a shopping mall environment and calls for more rigour in investigating the effectiveness of atmospheric stimuli in general

    The Ithaca Interpretation of Quantum Mechanics

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    I list several strong requirements for what I would consider a sensible interpretation of quantum mechanics and I discuss two simple theorems. One, as far as I know, is new; the other was only noted a few years ago. Both have important implications for such a sensible interpretation. My talk will not clear everything up; indeed, you may conclude that it has not cleared anything up. But I hope it will provide a different perspective from which to view some old and vexing puzzles (or, if you believe nothing needs to be cleared up, some ancient verities.)Comment: 21 pages, plain TEX. Notes for a lecture given at the Golden Jubilee Workshop on Foundations of Quantum Theory, Tata Institute, Bombay, September 9-12, 199

    A Calculus of Bounded Capacities

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    Resource control has attracted increasing interest in foundational research on distributed systems. This paper focuses on space control and develops an analysis of space usage in the context of an ambient-like calculus with bounded capacities and weighed processes, where migration and activation require space. A type system complements the dynamics of the calculus by providing static guarantees that the intended capacity bounds are preserved throughout the computation

    Memory with memory in genetic programming

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    We introduce Memory with Memory Genetic Programming (MwM-GP), where we use soft assignments and soft return operations. Instead of having the new value completely overwrite the old value of registers or memory, soft assignments combine such values. Similarly, in soft return operations the value of a function node is a blend between the result of a calculation and previously returned results. In extensive empirical tests, MwM-GP almost always does as well as traditional GP, while significantly outperforming it in several cases. MwM-GP also tends to be far more consistent than traditional GP. The data suggest that MwM-GP works by successively refining an approximate solution to the target problem and that it is much less likely to have truly ineffective code. MwM-GP can continue to improve over time, but it is less likely to get the sort of exact solution that one might find with traditional GP

    On the nature of continuous physical quantities in classical and quantum mechanics

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    Within the traditional Hilbert space formalism of quantum mechanics, it is not possible to describe a particle as possessing, simultaneously, a sharp position value and a sharp momentum value. Is it possible, though, to describe a particle as possessing just a sharp position value (or just a sharp momentum value)? Some, such as Teller (Journal of Philosophy, 1979), have thought that the answer to this question is No -- that the status of individual continuous quantities is very different in quantum mechanics than in classical mechanics. On the contrary, I shall show that the same subtle issues arise with respect to continuous quantities in classical and quantum mechanics; and that it is, after all, possible to describe a particle as possessing a sharp position value without altering the standard formalism of quantum mechanics.Comment: 26 pages, LaTe

    Quenched Spin Tunneling and Diabolical Points in Magnetic Molecules: II. Asymmetric Configurations

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    The perfect quenching of spin tunneling first predicted for a model with biaxial symmetry, and recently observed in the magnetic molecule Fe_8, is further studied using the discrete phase integral (or Wentzel-Kramers-Brillouin) method. The analysis of the previous paper is extended to the case where the magnetic field has both hard and easy components, so that the Hamiltonian has no obvious symmetry. Herring's formula is now inapplicable, so the problem is solved by finding the wavefunction and using connection formulas at every turning point. A general formula for the energy surface in the vicinity of the diabolo is obtained in this way. This formula gives the tunneling apmplitude between two wells unrelated by symmetry in terms of a small number of action integrals, and appears to be generally valid, even for problems where the recursion contains more than five terms. Explicit results are obtained for the diabolical points in the model for Fe_8. These results exactly parallel the experimental observations. It is found that the leading semiclassical results for the diabolical points appear to be exact, and the points themselves lie on a perfect centered rectangular lattice in the magnetic field space. A variety of evidence in favor of this perfect lattice hypothesis is presented.Comment: Revtex; 4 ps figures; follow up to cond-mat/000311
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