An optimized GPU implementation of a 2D free surface simulation model on unstructured meshes

This work is related with the implementation of a finite volume method to solve the 2D Shallow Water Equations on Graphic Processing Units (GPU). The strategy is fully oriented to work efficiently with unstructured meshes which are widely used in many fields of Engineering. Due to the design of the GPU cards, structured meshes are better suited to work with than unstructured meshes. In order to overcome this situation, some strategies are proposed and analyzed in terms of computational gain, by means of introducing certain ordering on the unstructured meshes. The necessity of performing the simulations using unstructured instead of structured meshes is also justified by means of some test cases with analytical solution.     

Identification of smooth nonlinear dynamical systems with non-smooth steady-state features

This work discusses the identification of single-block smooth nonlinear discrete-time polynomial models with non-smooth steady-state features. Based on bifurcation theory, conditions are developed and used to determine some general aspects of the model structure and also to determine some constraints on the parameters required to guarantee the aforementioned features. The procedure uses only smooth functions of the regressors, a single possibly smooth input and some prior knowledge about the steady-state behavior. The non-smooth static function is here obtained by interchanging the stability of two sets of equilibria at the break-point, which corresponds to guaranteeing a transcritical bifurcation. This work discusses how to determine the domain over which the results are valid. The procedure is illustrated with simulated and experimental data.     

科研型企业的计划调度算法研究与应用

针对科研型企业生产任务的特殊性,引入工种实力以综合反映多项资源的最大负载,讨论了工种实力的定义及评定指标,对不同类型的生产任务给出了基于综合优先级和工种实力的计划调度算法,介绍了在某研究所的具体应用情况。     

Data encryption in ISO,the International Organization for Standardization

The historical development from the start of work on data encryption up to the foundation of Sub-Committee SC 20 within ISO/97 is reviewed. The scope and programme of work are expounded, while some aspects of possible future developments and the impact of standardization in the field of data encryption are discussed.     

Control principles in flexible manufacturing

Flexible manufacturing systems present a setting in which application of control concepts can be crucial. Today, some concepts are in place where needed, some are waiting to be applied, and some are yet to be created. This paper is a status report on FMS control technology, based on ongoing work at the The Charles Stark Draper Laboratory in the development of decision support systems for FMSs.     

Data encryption in ISO,the International Organization for Standardization

The historical development from the start of work on data encryption up to the foundation of Sub-Committee SC 20 within ISO/97 is reviewed. The scope and programme of work are detailed and some aspects of possible future developments and the impact of standardization in the field of data encryption are discussed.     

支持CSCW的系统集成框架的设计与实现

结合CSCW系统的开发,对集中式CSCW系统结构的特点进行综合和提炼,设计并实现了一个基于构件及构件代理的应用集成框架。这个集成框架不仅对个体工作提供支持,同时对协同工作也提供支持。首先论述该框架的基本组成及各组成模块的主要功能,然后对该框架所提供的诸如工作流管理、电子会议等通用工具的功能进行了介绍。     

‘Adaptive’ and ‘Cooperative’ computer systems — A challenge for sociological research

The vision of the new generation of office systems is based on the hypothesis that an automatic support system is all the more useful and acceptable, the more systems behaviour and performance are in accordance with features ofhuman behaviour. Consequently recent development activities are influenced by the paradigm of the computer as man's “cooperative assistant”. The metaphors ofassistance andcooperation illustrate some major requirements to be met by new office systems. Cooperative office systems will raise a set of new questions about the future of human work, human-machine interaction, the forms of individual control of work, the scope of action and the development of competence in the frame of AI-supported cooperative work, the relative benefits of different types of organizations, etc. With increasing autonomy of the computer in task accomplishment, research should also be concerned with the question of the limits of such a development. In AI-research and development there is much discussion of the intended performance of that new technology. Perhaps this will provide insights into, how these new machines should support numerous aspects of individual or cooperative work. But we find fewer ideas about the future ofhuman work. What will the role of thehuman actor be in future AI-supported cooperative work? What kind of work do we want to support with AI-machines? In the following article I will try to identify some questions for further sociological research activities. I will base my considerations on some theoretical aspects ofunderstanding andmeaning. Regarding identical and non-identical aspects in communication behaviour of human and machines, I will focus on some questions to be investigated. Finally some methodological problems of sociological research in the field of Artificial Intelligence will be discussed, especially the so-called “Time-Dilemma” of sociological research in technology.     

无线传感器网络研究综述

无线传感器网络作为计算、通信和传感器三项技术相结合的产物,是一种全新的信息获取和处理技术。在简要介绍无线传感器网络体系结构的基础上,分析和展望了一些有价值的应用领域。结合已有研究,从数据采集、数据计算和路由协议三方面介绍无线传感器网络的研究现状,并着重介绍了目前无线传感器网络采用的路由技术,最后指出了下一步的研究方向。     

Space-repair cost optimal series-parallel systems

Optimization methods for reliability systems on diversified criteria for varied types of models are being increasingly developed. Venugopal et at. (1986–1989) have initiated notable lines of work in this direction for a large class of reliability models considering some comprehensive types of cost functions. This paper adds to this work in terms of considering the complex models, namely the series–parallel reliability system. A methodology is developed with the help of an algorithm to obtain cost-space optimal systems in a class of series parallel models based on practical cost considerations. The operational use of the theoretical work is brought out through some empirical results. A qualitative analysis is also provided as a useful companion study.     

Redistribution strategies for portable parallel FFT: a case study

The best approach to parallelize multidimensional FFT algorithms has long been under debate. Distributed transposes are widely used, but they also vary in communication policies and hence performance. In this work we analyze the impact of different redistribution strategies on the performance of parallel FFT, on various machine architectures. We found that some redistribution strategies were consistently superior, while some others were unexpectedly inferior. An in-depth investigation into the reasons for this behavior is included in this work. Copyright © 2001 John Wiley & Sons, Ltd.     

余Frame范畴中同余和同态关系的相关性质

以余Frame为对象,主要介绍了余Frame的相关概念和相关基本性质;研究了余Frame中的同余关系和同态关系的相关性质。研究的结果是对余Frame研究工作的补充和完善。     

时延驱动的布线算法最新研究进展

现有时延驱动布线算法的工作主要分为三个方面:时延模型、目标形式化、解空间。论文以时延模型为主线,介绍了近10年来提出的时延驱动的布线算法。在对各算法尤其是non-Hanan框架下的各优化算法进行深入分析的基础上,得出了一些有益的结论,并指出了进一步工作的方向。     

开放的缺省理论

本文基于开放逻辑理论，给出了缺省理论Ｔ＝＜Ｄ，Ｗ＞扩充Ｅ的新假设，事实反驳、ｅ－重构、ｅ－认识进程及其极限等概念的意义，讨论了Ｗ变化时新扩充的变化规律，并证明了相关的定理，本文还建立了缺省理论的一个动态描述过程，证明了其极限是某一特定问题的经验公式集，最后与相关工作进行了比较。     

On Social Constraints for Rational Agents

We define and study social constraints for rational agents. Our work is complementary to work on mechanism design in economics and Distributed Artificial Intelligence, as well as to work on artificial social systems. In our setting agents are rational but obey social laws that are imposed by the system's designer. Agents can be obliged to obey some social constraints, but not any constraint can serve as part of the social law. The main theme of our work is the study of settings where there are restrictions on the constraints that can serve as social laws. In such settings the designer should find social laws that can be imposed on the agents, and that will lead rational agents to satisfactory behavior. Our study is carried out in the context of zero‐sum and general‐sum games (with complete and with incomplete information) in extensive form.     

Reply

The authors of the previous discussion claim a counterexample to the theorem in Larson's work. This counterexample is not valid because of their incorrect interpretation of the extension to the multistage case. They do, however, present the correct interpretation of this extension. These points are discussed in some detail in this reply, as well as some additional results on conditions under which the theorem is valid and some comments on the practical value of the theorem.     

关于提高设备可靠性的几点思考

现如今各种设备的发展可谓日新月异,为适应设备发展的需要,本文针对如何提高设备可靠性提出几点个人的建议,并结合个人的工作经验举出若干实例,在对比中突出提升设备可靠性的总体思路,所总结的需要注意和提高的各个方面内容具有一定的现实意义,其思考思路和方向对于提升设备可靠性要求具有一定的探索价值。     

Conditions for maintaining ageing operators at work--a case study conducted at an automobile manufacturing plant

This is a case study on work/ageing relations in an automobile manufacturing company, where demographic trends and the work organisation determine the conditions under which ageing operators can work in repetitive tasks under tight time constraints. The methodology used is based on a comparison of different age operators at their regular workstation and in a new job, during the training process. The older workers appear to develop health-preserving strategies of work while achieving production goals. The possibility of setting up such strategies depends on the job characteristics. More generally, this case study allows us to better understand why some older workers are excluded from certain workstations, and thus why "polyvalency" or job rotation decreases with age.