摘要：
To guarantee network Quality of Service (QoS), network controllers designed and applied in real networks are necessary. How to automatically find efficient parameters of a controller and get the setting time of control system in simulation is a common problem in the process of controller design. Some definitions, experience rules and algorithms based on statistical theory are proposed in this paper, which are able to get the setting time, judge the stability feature of network control system and compare the control effects of different controllers. We tested the algorithms with network congestion controllers and the experiments results show that they are efficient to network controller evaluation, which enlarge the testing range and facilitate controller design.
作者机构：
[Tan, LS; Pugh, AC] Department of Computer Science, Central China Normal University, Wuhan 430079, China
通讯机构：
[Tan, LS ] ;Cent China Normal Univ, Dept Comp Sci, Wuhan 430079, Peoples R China.
摘要：
The non-standard H<inf>∞</inf> control problem is the case where the direct feedthroughs from the input to the error and from the exogenous signal to the output are not necessarily of full rank. In this paper, this problem is reformulated based on the generalized chain-scattering representation (GCSR). The GCSR approach leads naturally to a generalization of the homographic transformation. The state-space realization for this generalized homographic transformation and a number of fundamental cascade structures of the H<inf>∞</inf> control systems are further studied in a unified framework of GCSR. Certain sufficient conditions for the solvability of the non-standard H<inf>∞</inf> control problem are therefore established via a (J,J′)-lossless factorization of GCSR. These results present extensions to Kimura's results on the chain-scattering representation (CSR) approach to the H<inf>∞</inf> control in the standard case.
摘要：
The present paper proposes a control-theoretic approach to design rate-based controllers in order to flow-regulate the best-effort service and guaranteed service traffic through asynchronous transfer mode (ATM) switching networks. Classical control theory and Schur-Cohn stability criterion are exploited to design the traffic controllers for ATM switching networks. The stability and transient response of closed-loop congestion controlled systems are analyzed by utilizing Schur-Cohn stability criterion, which leads to certain necessary and sufficient stability condition under which the controlled ATM switching network is asymptotically stable in terms of buffer occupancy. Such proposed stability condition is then shown to be a key tool in designing a wide scope of adaptive controllers. Simulations are performed that show good performance of such controlled networks.
作者机构：
[Wang, ZJ; Wang, ZY; Chen, L] CENT CHINA NORMAL UNIV,DEPT COMP SCI,WUHAN 430070,PEOPLES R CHINA.;[Wang, ZY] WUHAN DIGITAL ENGN INST,WUHAN 430074,PEOPLES R CHINA.
通讯机构：
[Wang, ZY] W;WUHAN DIGITAL ENGN INST,WUHAN 430074,PEOPLES R CHINA.
关键词：
Ada program complexity;concurrent program;rendezvous;successive relation;nesting relation
摘要：
Concurrency of a multi-task program is presented by its communicating and synchronizing behavior between tasks. In Ada, this behavior is expressed as rendezvous relations between them. Difficulties in understanding a program lie in understanding their rendezvouses and relations between them. Rendezvous successive and nesting relations are introduced. Successive graph and nesting tree are used for modeling these relations. Finally, it is proposed that concurrent complexity CC(P) of an Ada program P is a weighted sum of successive complexity SC(P) and nesting complexity NC(P), and SC(P) is the sum of edge numbers of rendezvous successive graphs and NC(P) is the sum of weighted node numbers on rendezvous nesting trees constructed from rendezvous relations which can be identified statically in Ada program text.
