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11.
The problem of perfect regulation is to design a family of control laws for a given plant such that the resulting overall closed-loop system is internally stable and its controlled output can be reduced to zero arbitrarily fast from any initial condition. Such a problem was heavily studied by many researchers in the 1970s and early 1980s. However, to the best of our knowledge, all of the earlier results deal only with the problem under full state feedback. In this paper, we solve the long-standing problem of perfect regulation via measurement output feedback for general linear time-invariant multivariable systems. In particular, we derive necessary and sufficient conditions under which the problem of perfect regulation via measurement output feedback is solvable for general systems, and, under these conditions, construct two families of feedback laws, one of full order and the other reduced order, that solve the problem.  相似文献   
12.
Network visualization by semantic substrates   总被引:1,自引:0,他引:1  
Networks have remained a challenge for information visualization designers because of the complex issues of node and link layout coupled with the rich set of tasks that users present. This paper offers a strategy based on two principles: (1) layouts are based on user-defined semantic substrates, which are non-overlapping regions in which node placement is based on node attributes, (2) users interactively adjust sliders to control link visibility to limit clutter and thus ensure comprehensibility of source and destination. Scalability is further facilitated by user control of which nodes are visible. We illustrate our semantic substrates approach as implemented in NVSS 1.0 with legal precedent data for up to 1122 court cases in three regions with 7645 legal citations  相似文献   
13.
介绍了以MCS-51系列单片机为核心的定量检测系统的基本原理。并对其硬件结构和软件设计进行了详细地介绍。  相似文献   
14.
综述了物理化学在化学工业中的应用,着重阐述了热力学、动力学、电化学、离子液体、超临界流体在化学工业中的实际应用情况,并对该领域的研究发展方向进行了初步的探讨.  相似文献   
15.
Within the field of Information Systems, a good proportion of research is concerned with the work organisation and this has, to some extent, restricted the kind of application areas given consideration. Yet, it is clear that information and communication technology deployments beyond the work organisation are acquiring increased importance in our lives. With this in mind, we offer a field study of the appropriation of an online play space known as Habbo Hotel. Habbo Hotel, as a site of media convergence, incorporates social networking and digital gaming functionality. Our research highlights the ethical problems such a dual classification of technology may bring. We focus upon a particular set of activities undertaken within and facilitated by the space—scamming. Scammers dupe members with respect to their ‘Furni’, virtual objects that have online and offline economic value. Through our analysis we show that sometimes, online activities are bracketed off from those defined as offline and that this can be related to how the technology is classified by members—as a social networking site and/or a digital game. In turn, this may affect members’ beliefs about rights and wrongs. We conclude that given increasing media convergence, the way forward is to continue the project of educating people regarding the difficulties of determining rights and wrongs, and how rights and wrongs may be acted out with respect to new technologies of play online and offline.
Ben LightEmail:

Marie Griffiths   moved from the IT industry into academia and is now based at the University of Salford as an EPSRC Academic Fellow. She has, and continues to research gender and ICTs. Recently she has embarked upon the study “Cybercitizens and their Virtual Pursuits” to understand the consequence of growing up and living in a technologically saturated environment. Her work has been published in journals such as Gender, Work and Organization, the European Journal of Information Systems and Information Communication and Society. Ben Light   is Professor of Technology and Society at the University of Salford. His research concerns the appropriation of configurable technologies within work, organisations and society. This has led him to explore the use of large-scale enterprise resource planning packages, call centre technologies, social networking sites and digital games. He has published in journals such as Communications of the ACM, Information Systems Journal, New Technology, Work and Employment, the European Journal of Information Systems and the Journal of Information Technology.  相似文献   
16.
ATM switch, the core technology of an ATM networking system, is one of the major products in Fujitsu telecommunication business. However, current gate–level design methodology can no longer satisfy its stringent time–to–market requirement. It becomes necessary to exploit high–level methodology to specify and synthesize the design at an abstraction level higher than logic gates. This paper presents our prototyping experience on domain–specific high–level modeling and synthesis for Fujitsu ATM switch design. We propose a high–level design methodology using VHDL, where ATM switch architectural features are considered during behavior modeling, and a high–level synthesis compiler, MEBS, is prototyped to synthesize the behavior model down to a gate–level implementation. Since the specific ATM switch architecture is incorporated into both modeling and synthesis phases, a high–quality design is efficiently derived. The synthesis results shows that given the design constraints, the proposed high–level design methodology can produce a gate–level implementation by MEBS with about 15 percent area reduction in shorter design cycle when compared with manual design.  相似文献   
17.
Since browsing hypertext can present a formidable cognitive challenge, user interface design plays a major role in determining acceptability. In the Unix workstation version of Hyperties, a research-oriented prototype, we focussed on design features that facilitate browsing. We first give a general overview of Hyperties and its markup language. Customizable documents can be generated by the conditional text feature that enables dynamic and selective display of text and graphics. In addition we present: — an innovative solution to link identification: pop-out graphical buttons of arbitrary shape.

— application of pie menus to permit low cognitive load actions that reduce the distraction of common actions, such as page turning or window selection.

— multiple window selection strategies that reduce clutter and housekeeping effort. We preferred piles-of-tiles, in which standard-sized windows were arranged in a consistent pattern on the display and actions could be done rapidly, allowing users to concentrate on the contents.

  相似文献   
18.
To get precise material data for advanced numerical modelling of tube hydroforming process, the tube bulging test is recommended. Stresses and strains in the tube cannot be evaluated easily and several approaches have been proposed. A review is proposed and points out their advantages and drawbacks.  相似文献   
19.
彭犇  岳昌盛  陆璇  郭敏  张梅 《硅酸盐通报》2010,29(1):167-170
以煤矸石和碳黑为主要原料,在1800 K下碳热还原氮化合成了纯度较高、含有大量晶须的β-SiAlON材料.FESEM照片表明β-SiAlON晶须多为细长柱状,直径120~220 nm,长度1.5~5 μm,晶须生长机制由VLS(vapor-liquid-solid)机制和VS(vapor-solid)机制组成.  相似文献   
20.
针对当前检测方法准确率不高以及模型泛化性较差的问题,提出了基于KOLSTM深度学习模型的蜜罐陷阱合约检测方法.首先,通过分析蜜罐陷阱合约的特点,提出了关键操作码的概念,并设计了可用于选取智能合约中关键操作码的关键词提取方法;其次,在传统的LSTM模型中加入关键操作码权重机制,构建了可以同时捕获蜜罐陷阱合约中隐藏的序列特...  相似文献   
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