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Those who have worked in the Royal Institution of Great Britain have, since its foundation in 1799, made significant contributions to scientific knowledge, to its practical application, and to its communication to a wide variety of audiences. Such work cannot be carried out in an architectural vacuum, and in this paper we examine how the buildings of the Royal Institution, 20 and 21 Albemarle Street in central London, have shaped the work undertaken within its walls and how, on a number of occasions, the buildings have been reconfigured to take account of the evolving needs of scientific research and communication. This paper is based on the Conservation Plan of the Royal Institution that we wrote during 2003. The Conservation Plan did not examine the land owned by the Royal Institution to the north (i.e., 22 and 23 Albemarle Street; for this area see Richard Garnier, “Grafton Street, Mayfair,” Georgian Group Journal 13 (2003), 210–272), but it did discuss 18 and 19 Albemarle Street. In this paper we concentrate on the core Royal Institution buildings at 20 and 21 Albemarle Street. Other studies of the relationship of architecture,space, and science include Crosbie Smith and Jon Agar, ed., Making Space for Science: Territorial Themes in the Shaping of Knowledge (Basingstoke: Macmillan, 1997); Peter Galison and Emily Thompson, ed., The Architecture of Science (Cambridge, Mass.: MIT Press, 1999); and Sophie Forgan,“The architecture of science and the idea of a university,” Studies in History and Philosophy of Science 20 (1989), 405–434. Frank A.J.L. James is Professor of the History of Science at the Royal Institution; he has written widely on the history of nineteenth-century science in its social and cultural contexts and is editor of the Correspondence of Michael Faraday. He is President of the British Society for the History of Science. Anthony Peers is an Associate of Rodney Melville and Partners where he works in the field of building conservation as an architectural historian. He is a Council member of the Ancient Monument Society.  相似文献   
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Suppose that (Xt)t0 is a one-dimensional Brownian motion with negative drift ?μ. It is possible to make sense of conditioning this process to be in the state 0 at an independent exponential random time and if we kill the conditioned process at the exponential time the resulting process is Markov. If we let the rate parameter of the random time go to 0, then the limit of the killed Markov process evolves like X conditioned to hit 0, after which time it behaves as X killed at the last time X visits 0. Equivalently, the limit process has the dynamics of the killed “bang–bang” Brownian motion that evolves like Brownian motion with positive drift +μ when it is negative, like Brownian motion with negative drift ?μ when it is positive, and is killed according to the local time spent at 0.An extension of this result holds in great generality for a Borel right process conditioned to be in some state a at an exponential random time, at which time it is killed. Our proofs involve understanding the Campbell measures associated with local times, the use of excursion theory, and the development of a suitable analogue of the “bang–bang” construction for a general Markov process.As examples, we consider the special case when the transient Borel right process is a one-dimensional diffusion. Characterizing the limiting conditioned and killed process via its infinitesimal generator leads to an investigation of the h-transforms of transient one-dimensional diffusion processes that goes beyond what is known and is of independent interest.  相似文献   
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Physicist Lee A. DuBridge became president of the California Institute of Technology in 1946. In this interview he recalls his dealings at Caltech with Linus Pauling; his memories of George W. Beadle, Theodore von Kármán, and J. Robert Oppenheimer; the military Vista Project at Caltech; and the difficulties surrounding the deportation of Hsue-Shen Tsien, Caltech's Goddard Professor of Jet Propulsion.  相似文献   
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Abstract

This article studies classes of random measures on topological spaces perturbed by stochastic processes (a.k.a. modulated random measures). We render a rigorous construction of the stochastic integral of functions of two variables and showed that such an integral is a random measure. We establish a new Campbell-type formula that, along with a rigorous construction of modulation, leads to the intensity of a modulated random measure. Mathematical formalism of integral-driven random measures and their stochastic intensities find numerous applications in stochastic models, physics, astrophysics, and finance that we discuss throughout the article.  相似文献   
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The role of optimization is central to economic analysis, particularly in its “neoclassical” phase, since about 1870, and is therefore highly compatible with the impulse behind linear programming (LP), as developed by Dantzig. LP’s stress on alternative activities fits very well with modern economic analysis. The concept of economic equilibrium, properly understood, required the central notion of complementary slackness. so central in LP.

LP was seen as a tool for actual implementation of neoclassical principles precisely at a time when the market was under attack from several directions. The economists Koopmans and Hurwicz played an important role both in stimulating the crucial development of the simplex method and in relating LP to the world of economics.

LP became widely used in national economic planning, particularly for developing countries, and for the study of individual industries, especially the energy sector. The works of Chenery and of Manne are central in these fields.

As respect for the usefulness of the market increased, the emphasis on national planning diminished and was replaced by an emphasis on equilibrium analysis, in which LP still plays a large part in the study of individual sectors, particularly energy.  相似文献   

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George Boole and the origins of invariant theory   总被引:1,自引:0,他引:1  
Historians have repeatedly asserted that invariant theory was born in two papers of George Boole (1841 and 1842). Although several themes and techniques of 19th-century invariant theory are enunciated in this work, in reacting to it (and thereby founding the British school of invariant theory), Arthur Cayley shifted Boole's research program.  相似文献   
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We pay homage to George B. Dantzig by describing a less well-known part of his legacy–his early and dedicated championship of the importance of systems optimization in solving complex real-world problems.  相似文献   
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厚宇德 《大学物理》2006,25(3):46-49
乔治.格林是一位重要的数学物理学家.简要介绍了乔治.格林的生平和科学研究经历,揭示了帮助他取得重要科学研究成果的主要因素,介绍了格林函数法的建立过程及其重要性.  相似文献   
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