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31.
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   
32.
在四阳极直流放电装置上,测量并分析了辉光放电的电流-电压和发光特征随气压的变化关系。结果表明,采用稳流放电模式比稳压放电具有更宽的稳定放电气压和电流范围,能在从1~800Pa的较宽气压范围内实现氦气辉光放电,放电电流可达到500mA左右。随着电极表面亮斑的变化,对于同一气压,在低电流区,放电电压几乎成指数增长;随电流增大,电压的增长速度变缓;对于高的气压,碰撞频率的增大使得电压随电流升高的速率变小。分析表明,放电处于异常辉光区。从放电管的CCD图像可以看出,对于同一放电电流,随气压的升高,等离子体往阴极收缩。  相似文献   
33.
C/S与B/S体系结构在信息查询系统中的应用   总被引:5,自引:0,他引:5  
阐述了将数据库体系结构中的Client/Server结构与Browser/Server结构混合应用于水情信息查询系统,以实现对水情信息的处理和查询。  相似文献   
34.
研究了用SiO2 +Al作掩模 ,SF6 +O2 混合气体等离子体对Si的横向刻蚀 ,其结果表明 ,在SF6 +O2 等离子体气氛中 ,Al是很好的保护膜 ,可以在待悬浮器件下形成大的开孔。因此 ,预计用这种技术 ,可以在Si片上集成横向尺寸为数百微米 ,具有优良高频性能的MEMSRF/MW无源器件 ,如开关、传输线、电感和电容等。  相似文献   
35.
未来十年综合航电系统的发展趋向   总被引:4,自引:4,他引:0  
汪桂华 《电讯技术》2002,42(6):23-26
本文主要阐述未来十年国外综合航电系统的总的发展趋向,重点介绍了在开放式系统结构的研究与应用、采用COTS技术、模块化、多传感器综合技术等方面的发展趋向。  相似文献   
36.
本文对IGBT模块中功率芯片(IGBT和续流二极管)的优化设计进行了讨论。通过优化几个重要的工艺参数并改进器件的结构,IGBT不仅有足够的短路容量,而且正向压降与电流下降时间之间可实现最佳折衷。另外,续流二极管的反向恢复特性也有明显改善。通过采用衬底控制技术,IGBT模块的输出特性不受温度的影响,输出电流更稳,输出阻抗更高。本文详细介绍了整个设计考虑。  相似文献   
37.
To provide responsive information services in a ubiquitous computing environment, service software and system development are indispensable. A component-based ubiquitous information system with a JAIN (Java APIs for Integrated Networks) platform to achieve seamless transmissions and reach-everywhere communications was designed in our research. In this development, numerous ubiquitous service modules were identified: location management, roaming, mobile IP and WAP networking. These component-based network modules were constructed using a component composition language with component specification and interface definition, running on top of a distributed service architecture using a JAIN platform to distribute the ubiquitous information services to mobile users. Two applications, Wireless-Application-Protocol (WAP) Mail and Video-on-Demand (VoD) services, show that the JAIN-like platform with the developed networking components effectively fills the gap for application developers between mobile appliances and various kinds of ubiquitous information services.  相似文献   
38.
XML在机械CAD系统中的应用   总被引:5,自引:0,他引:5  
分析了Internet上最新的XML技术的特点,通过实例用XML技术对机械CAD产生的各种文档信息进行了描述,并且构造了基于XML文档交换的分布式支持环境的体系结构。  相似文献   
39.
Previous work carried out in our laboratories has focused on the formation and investigation of a dextran and concanavalin A (con A) based gel, which has the ability to alter its conformational structure in the presence and absence of free and terminal glucoses such that a gel–sol phase transition occurs. Here we report the diffusion and rheological investigations in to the effects of the addition of insulin and varyingconcentrations of magnesium chloride hexahydrate (Mg2Cl26H2O) at 20 and 37 °C. Rheological examination of glucose-sensitive (dextran-con A) gels were conducted using a cone and plate viscometer used in continual rotation and oscillatory modes. The results are interpreted in terms of the structure of the gel network and suggest rheological assessment provides an effective method of assessing the properties of gel systems. The subsequent testing of such formulations in in-vitro diffusion experiments revealed a reduction in the rate of diffusivity in the insulin marker, poly R-478 dye. The performance of this self-regulating drug delivery system has been examined and the addition of insulin and magnesium chloride may alter the way in which the gel operates as a drug delivery device and in the delivery of insulin. This may have implications for other ligands.  相似文献   
40.
An implementation for a fast public-key cryptosystem   总被引:9,自引:0,他引:9  
In this paper we examine the development of a high-speed implementation of a system to perform exponentiation in fields of the form GF(2 n ). For sufficiently large n, this device has applications in public-key cryptography. The selection of representation and observations on the structure of multiplication have led to the development of an architecture which is of low complexity and high speed. A VLSI implementation has being fabricated with measured throughput for exponentiation for cryptographic purposes of approximately 300 kilobits per second.  相似文献   
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