网格计算中的开放复杂巨系统

在处理复杂巨系统问题时,本文利用对特定问题的求解策略,以网格技术作为支撑,有效地综合集成计算机网络中的各种资源,不仅能够对数据库、方法库等高层资源进行集成,而且可以将计算能力、存储能力、网络资源,甚至硬件设备和人都进行有效的集成,提供一个协作的、高效的、开放的网格巨系统.     

一个正在发展中的新领域——开放的复杂巨系统

本文对复杂性、复杂系统、复杂巨系统的研究作了介绍.说明这是一类用还原论方法处理不了而需要新的方法论来研究问题,这是一个科学新领域,在理论上和实践中都有重要意义.     

开放的复杂巨系统Internet可存活性需求分析框架

传统的安全概念已不适应今天开放环境下的复杂信息系统。随着现代社会对Internet依赖性的增加,计算机网络系统的可存括性的需求成为亟待解决的问题。该文分析了Internet可存活性的重要性,提出了可存活性的需求框架,并使用HWMSE作为测试和评估网络系统可存活能力的方法,为提高巨型计算机网络的可存活性提供了有效的解决途径。     

FIPA规范：Agent系统的开放标准

1.引言 FIPA(The Foundation for Intelligent Physical Agents)是一个由活跃在Agent领域的公司和学术机构组成的国际组织,其目标是为异质的Agent和Agent系统之间能够互操作而制订相关的软件标准。 FIPA规范的制订过程是开放的,它的每一个会员组织都有权对规范提出自己的意见和建议,在充分讨论的基础上达成一致。FIPA组织本身也是开放的,任何公司、政府机构和国际组织都可以申请加入FIPA。FIPA与OMG(ObjectManagement Group)等标准化组织也保持着密切的工作关系。     

复杂系统的定性仿真

回顾复杂系统定性仿真的发展历程;阐述复杂系统定性仿真的基本原理,将定性仿真方法归纳为非因果关系推理、因果关系推理和元胞自动机三类;评述三类方法的研究和应用进展;探讨管理系统复杂性的特征,介绍本文作者及其合作者的管理系统定性仿真研究工作;给出复杂系统定性仿真下一步需要解决的关键问题。     

一种开放混合实时系统的开放自适应调度算法

开放计算环境下的实时与非实时任务不确定并发,以及多种实时约束混合的复杂约束系统,即开放混合实时系统的需求越来越广泛.通过引入接收控制、调度服务器、自适应调节机制,提出一种开放环境下的自适应实时系统调度架构--OARtS(open adaptive real-time scheduling).它能适应开放计算环境的不确定性,有控制地接受实时任务运行;可根据系统空闲计算带宽变化,自适应地调节任务的实时等级,使得系统运行在最优的实时性能上;对于软实时任务,可根据其计算带宽需求变化,自适应地调节其计算带宽分配,以适应任务执行时间时变引起的实时不确定性.     

Integration and Test Sequencing for Complex Systems

The integration and test phase of complex manufacturing machines, like an ASML lithographic manufacturing system, is expensive and time consuming. The tests that can be performed at a certain point in time during the integration phase depend on the modules that are integrated and, therefore, on the preceding integration sequence. In this paper, we introduce a mathematical model to describe an overall integration and test sequencing problem, and we propose an algorithm to solve this problem. The method is a combination of integration sequencing and test sequencing. Furthermore, we introduce several strategies that determine when test phases should start. With a case study within the development of a software release that is used to control an ASML lithographic machine, we show that the described method and strategies can be used to solve real-life problems.      

Complex Modified Projective Synchronization for Fractional-order Chaotic Complex Systems

The aim of this paper is to study complex modified projective synchronization (CMPS) between fractional-order chaotic nonlinear systems with incommensurate orders. Based on the stability theory of incommensurate fractional-order systems and active control method, control laws are derived to achieve CMPS in three situations including fractional-order complex Lorenz system driving fractional-order complex Chen system, fractional-order real Rössler system driving fractional-order complex Chen system, and fractional-order complex Lorenz system driving fractional-order real Lü system. Numerical simulations confirm the validity and feasibility of the analytical method.     

Queueing Theory for Semiconductor Manufacturing Systems: A Survey and Open Problems

This paper surveys applications of queueing theory for semiconductor manufacturing systems (SMSs). Due to sophisticated tool specifications and process flows in semiconductor manufacturing, queueing models can be very complicated. Research efforts have been on the improvement of model assumptions and model input, mainly in the first moment (averages) and the second moment (variations). However, practices show that implementation of classical queueing theory in semiconductor industry has been unsatisfactory. In this paper, open problems on queueing modeling of SMS are discussed. A potential solution is also proposed by relaxing the independent assumptions in the classical queueing theory. Cycle time reduction has constantly been a key focus of semiconductor manufacturing. Compared with simulation, queueing theory-based analytical modeling is much faster in estimating manufacturing system performance and providing more insights for performance improvement. Therefore, queueing modeling attracts generous semiconductor research grants. Unfortunately, existing queueing models focus on simple extensions of the classical queueing theory and fail to question its applicability to the complicated SMS. Hence, related researches have not been employed widely in the semiconductor industry. In this paper, we conduct a survey on the important works and also present some open problems. We also propose a novel solution by relaxing a key assumption in the classical queueing theory. We are currently funded by Intel to explore this potential solution, and we hope it can foster an interesting research field for the years to come.     

Open Systems: A Perspective on Change

Because change is a constant occurrence in the IS environ-ment, important ones can often be overlooked. This column discusses several factors that are currently contributing to a significant change in the way systems will be developed in the 1990s—the use of open systems.     

复杂系统的递阶模糊辨识

针对Takagi_Sugeno模糊模型 (T_S模型 )严重的维数灾问题, 借鉴GMDH算法, 提出了一种新的复杂系统递阶模糊辨识方法. 本文首先详细描述了由两输入变量的特殊T_S模型所组成的递阶模糊模型 ;然后提出了具体的辨识该递阶模糊模型的方法. 该方法的特点是 :a)在结构辨识阶段, 用FCM模糊聚类方法评价系统中每个输入变量的重要性, 以便构造合理的递阶模糊模型 ;b)预先合理地确定了所要辨识的参数的初始值, 用扩展卡尔曼滤波方法可很快地得到这些参数. 最后, 给出的仿真实例说明了本文辨识方法的有     

基于拟非线性模糊模型的复杂系统模糊辨识

针对一阶Takagi－Sugeno[以下简称T－S]到模型辨识复杂系统的困难，本文提出了一种新的拟非线性模糊模型．即在一阶T－S模型的基础上，再进行一次非线性映射．这种模糊模型不仅具有较高的辨识精度，而且具有良好的泛化功能．运用改进的FCM（FuzzyC－Means）模糊聚类方法，辨识该模糊模型的结构，与以往的方法比较，极大地简化了结构辨识的复杂性．仿真结果进一步说明了该方法的有效性．     

基于拟非线性模糊模型的复杂系统模糊辨识

针对一阶Takagi-Sugeno（以下简称T-S）模型辨识复杂系统的困难，本文提出了一种新的拟非线性模糊模型。即在一阶T-S模型的基础上，再进行一次非线性映射。这种模糊模型不仅具有较高的辨识精度，而且具有良好的泛化功能。运用改进的FCM（Fuzzy-C-Means）模糊聚类方法，辨识该模糊模型的结构，与以往的方法比较，极大地简化了结构辨识的复杂性。仿真结果进一步说明了该方法的有效性。     

Hierarchical Test Sequencing for Complex Systems

Testing complex systems, such as the ASML TWINSCAN lithographic machine, is expensive and time consuming. In a previous work, a test sequencing method to calculate time-optimal test sequences has been developed. Because complex systems are composed of several subsystems, which are again composed of several modules, there exists a need to hierarchically model test sequencing problems. Such a hierarchical test sequencing problem consists of a high-level model that describes a test sequencing problem at the system level, and one or more low-level models that describe the test sequencing problems at the subsystem or module level. The tests at the system level correspond to the solutions of low-level problems. This paper describes a hierarchical test sequencing model and proposes two algorithms to compute an optimal test sequence. The benefits of hierarchically modeling a problem are less computational effort and less modeling effort, because not all relations are needed. This is illustrated by a small example. The industrial relevance of this method is illustrated on a case study related to a manufacturing testing phase of a lithographic machine.     

Open and Reconfigurable Hypermedia Systems: A Filter-Based Model

The need for open hypermedia systems has been well-argued by various authors. In this paper we discuss the Microcosm model for open hypermedia and show how filters have been used to extend this model both for greater efficiency and to make it totally reconfigurable. This enables users to tailor the functionality of the system to meet their own requirements, for example to select different sets of links, or to add navigation tools. The implementation of a management system for filters is described, and examples of how it has been used to extend the functionality of the model are presented, in particular the use of filters to design and implement a set of navigation tools for Microcosm. This latter case study demonstrates the power and flexibility of the filter-based model since all navigation tools for the system can be implemented as filters. The filter technology is discussed in the context of Microcosm but can be generalised to other hypermedia systems.     

复杂控制系统的开放控制平台

引言 复杂控制系统，例如飞行器、电力以及电信网络等系统的设计给控制系统工程师以极大的挑战，特别是军事应用中要求这些系统具有新的、高度复杂的性能，用传统的控制技术很难实现，主要包括以下几个方面： (1) 适应性/动态重配性 大型工程系统应该具有对系统的变化做出快速而良好响应的能力，这些变化包括环境的变化和不影响操作完整性情况下自身结构的变化。超级性能的动态系统必须能够支持算法组件的在线转换以及它们之间连接的快速重定向，并且能够改变信息流的优先级。这些性能对于混合控制系统来说非常重要。 (2) 即插即用可扩展…     

Algebraic Geometry and Computer Vision: Polynomial Systems, Real and Complex Roots

We review the different techniques known for doing exact computations on polynomial systems. Some are based on the use of Gröbner bases and linear algebra, others on the more classical resultants and its modern counterparts. Many theoretical examples of the use of these techniques are given. Furthermore, a full set of examples of applications in the domain of artificial vision, where many constraints boil down to polynomial systems, are presented. Emphasis is also put on very recent methods for determining the number of (isolated) real and complex roots of such systems.