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71.
This paper employs dissipativity theory for the global analysis of limit cycles in particular dynamical systems of possibly high dimension. Oscillators are regarded as open systems that satisfy a particular dissipation inequality. It is shown that this characterization has implications for the global stability analysis of limit cycle oscillations: i) in isolated oscillators, ii) in interconnections of oscillators, and iii) for the global synchrony analysis in interconnections of identical oscillators  相似文献   
72.
One of the crucial steps in the second generation high temperature superconducting wire program was development of the buffer-layer architecture. The architecture designed at the Superconductivity Technology Center at Los Alamos National Laboratory consists of several oxide layers wherein each layer plays a specific role, namely: nucleation layer, diffusion barrier, biaxially textured template, and intermediate layer providing a suitable lattice match to the superconducting Y1Ba2Cu3O7 (YBCO) compound. This report demonstrates how a wide range of ion beam analysis techniques (SIMS, RBS, channeling, PIXE, PIGE, NRA and ERD) was employed for analysis of each buffer layer and the YBCO film. These results assisted in understanding of a variety of physical processes occurring during the buffer layer fabrication and helped to optimize the buffer-layer architecture as a whole.  相似文献   
73.
国际无线通信联盟(ITU)于去年 11月在赫尔辛基会议上最终确立了IMT-2000标准。在不偏袒现有任何一个协议的情况下,这一协议为所有主要的无线通信协议提供了统一的3G(第三代)无线通信平台。有了IMT-2000标准,互相竞争的无线通信技术将在3G世界里共存,并可在一个框架下做到互相连接。 两年多来,无线系统供应商一直在为适用于第三代(3G)无线通信网络的最好平台争吵。一个无线平台的主要结构层包括一个基础的核心网络和相应编码、处理、传输的无线通信协议。为满足目前手机、PDA(个人数字助理)和其它…  相似文献   
74.
This paper presents a novel agent architecture, the VM-architecture, that chooses its actions via a behaviour instantiation mechanism inspired by Maes?s behaviour networks. The VM-architecture enables an agent, VMattie, built upon it, actively to gather information from humans using email in natural language, to compose announcements of next week?s seminars and to mail them each week to a list that she keeps updated. VMattie does all this without the supervision of a human. Implemented and tested in a UNIX environment, the system?s performance surpassed the authors? fondest hopes.  相似文献   
75.
This paper describes LEW (learning by watching), an implementation of a novel learning technique, and discusses its application to the learning of plans. LEW is a domain-independent learning system with user-limited autonomy that is designed to provide robust performance in realistic knowledge acquisition tasks in a variety of domains. It partly automates the knowledge acquisition process for different knowledge types, such as concepts, rules, and plans. The inputs to the system, which we call cues , consist of an environmental component and of pairs containing a problem and its solution. Unlike traditional forms of "learning from examples", in which the system uses the teacher's answer to improve the result of a prior generalization of an example, LEW treats the problem-solution or question-answer instances, i. e., the cues themselves, as the basic units for generalization.  相似文献   
76.
An organizational prototype is a forum to address simultaneously process, behavioral, and cultural change pursuant to business process redesign (BPR). in this case study, IS personnel facilitated organizational prototypes, thereby extending their knowledge of business systems to a new sphere, facilitating business process redesign. Success of the prototypes led to success in obtaining corporate funding for new client/server systems to support the changes in business operations.  相似文献   
77.
A new method for the qualitative and quantitative determination of trenbolone and testosterone residues in meat, liver, and kidney is described. The analytical procedure consists of the following steps: homogenisation of the meat sample with tetrahydrofurane; liquid-liquid partition first between acetonitrile and hexane, then between sodium hydroxide and petroleum ether/benzene; purification of a silica gel column. The purified sample is analysed by high pressure liquid chromatography using silica gel packings. Detection and quantitative determination are performed with a fluorescence and/or a spectrophotometric detector. Fluorescence measurements are carried out applying a self-made silica gel packed flow-cell. The detection limit in meat extracts is 50 ppb for testosterone and 5 ppb for trenbolone.  相似文献   
78.
The implementation of concepts of multiple land use seems to be relevant in the context of large-scale urban projects, which are now predominately monofunctional. However, current governance settings at these projects seem to be unreceptive to this new planning concept. Our in-depth case study of the South Axis project in Amsterdam embraces an actor-centred institutional perspective and seeks to understand how more receptive conditions for norm alignment between key actors can be attained. We reconstruct the introduction of quite radical concepts of multiple land use in this project, which started as an office-development proposal. The implementation was severely hampered by the fact that ambitions were formed in a rather introvert local government – business setting. Only in the last stage, with the adoption of a more extrovert mode of governance that included a variety of national government departments, were more receptive conditions for multiple land use created.  相似文献   
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