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991.
高性能PCB空心线圈电流互感器为大截面结构,而理想空心线圈电流互感器要求为小截面结构。文章通过详细的理论分析和推导,解除了对截面大小的这一限制,得出大截面、高精度的PCB空心线圈电流互感器具有和理想空心线圈电流互感器相同测量原理的结论,为PCB空心线圈电流互感器的优化设计和在矿区电力系统中的应用提供了理论基础。实验研究结果表明,高性能PCB空心线圈电流互感器具有良好的测量精度、参数一致性、优异的工频暂态性能和抗电磁干扰能力,适应矿区的电力环境和电力系统进一步数字化的发展潮流。 相似文献
992.
An experimental investigation of personality types impact on pair effectiveness in pair programming 总被引:1,自引:1,他引:0
Panagiotis Sfetsos Ioannis Stamelos Lefteris Angelis Ignatios Deligiannis 《Empirical Software Engineering》2009,14(2):187-226
In this paper, pair programming is empirically investigated from the perspective of developer personalities and temperaments
and how they affect pair effectiveness. A controlled experiment was conducted to investigate the impact of developer personalities
and temperaments on communication, pair performance and pair viability-collaboration. The experiment involved 70 undergraduate
students and the objective was to compare pairs of heterogeneous developer personalities and temperaments with pairs of homogeneous
personalities and temperaments, in terms of pair effectiveness. Pair effectiveness is expressed in terms of pair performance, measured by communication, velocity, design correctness and passed acceptance tests, and pair collaboration-viability measured by developers’ satisfaction, knowledge acquisition and participation. The results have shown that there is important
difference between the two groups, indicating better communication, pair performance and pair collaboration-viability for
the pairs with heterogeneous personalities and temperaments. In order to provide an objective assessment of the differences
between the two groups of pairs, a number of statistical tests and stepwise Discriminant Analysis were used.
Panagiotis Sfetsos is an Assistant Professor at the Department of Informatics at the Alexander Technological Educational Institute of Thessaloniki, Greece. He received his B.Sc. in Computer Science and Statistics from the University of Uppsala, Sweden (1981), and the Ph.D. degree in Computer Science from the Aristotle University of Thessaloniki (2007). His Ph.D. Thesis was on “Experimentation in Object Oriented Technology and Agile Methods”. His research interests include empirical software evaluation, measurement, testing, quality, agile methods and especially extreme programming. Ioannis G. Stamelos is an Associate Professor of Computer Science at the Aristotle University of Thessaloniki, Dept. of Informatics. He received a degree in Electrical Engineering from the Polytechnic School of Thessaloniki (1983) and the Ph. D. degree in Computer Science from the Aristotle University of Thessaloniki (1988). He teaches object-oriented programming, software engineering, software project management and enterprise information systems at the graduate and postgraduate level. His research interests include empirical software evaluation and management, software education and open source software engineering. He is author of 90 scientific papers and member of the IEEE Computer Society. Lefteris Angelis received his B.Sc. and Ph.D. degree in Mathematics from Aristotle University of Thessaloniki (A.U.Th.). He works currently as an Assistant Professor at the Department of Informatics of A.U.Th. His research interests involve statistical methods with applications in software engineering and information systems, computational methods in mathematics and statistics, planning of experiments and simulation techniques. Ignatios Deligiannis is an Associate Professor at Alexander Technological Education Institute of Thessaloniki, Greece. His main interests are Object-Oriented software methods, and in particular design assessment and measurement. He received his B.Sc. in Computer Science from Lund University, Sweden, in 1979, and then worked for several years in software development at Siemens Telecommunications industry. He was member of ESERG (Empirical Software Engineering Research Group at Bournemouth University, UK). Currently, he is a research partner of Software Engineering Group::Plase laboratory, Aristotle University of Thessaloniki, Greece. 相似文献
Ignatios DeligiannisEmail: |
Panagiotis Sfetsos is an Assistant Professor at the Department of Informatics at the Alexander Technological Educational Institute of Thessaloniki, Greece. He received his B.Sc. in Computer Science and Statistics from the University of Uppsala, Sweden (1981), and the Ph.D. degree in Computer Science from the Aristotle University of Thessaloniki (2007). His Ph.D. Thesis was on “Experimentation in Object Oriented Technology and Agile Methods”. His research interests include empirical software evaluation, measurement, testing, quality, agile methods and especially extreme programming. Ioannis G. Stamelos is an Associate Professor of Computer Science at the Aristotle University of Thessaloniki, Dept. of Informatics. He received a degree in Electrical Engineering from the Polytechnic School of Thessaloniki (1983) and the Ph. D. degree in Computer Science from the Aristotle University of Thessaloniki (1988). He teaches object-oriented programming, software engineering, software project management and enterprise information systems at the graduate and postgraduate level. His research interests include empirical software evaluation and management, software education and open source software engineering. He is author of 90 scientific papers and member of the IEEE Computer Society. Lefteris Angelis received his B.Sc. and Ph.D. degree in Mathematics from Aristotle University of Thessaloniki (A.U.Th.). He works currently as an Assistant Professor at the Department of Informatics of A.U.Th. His research interests involve statistical methods with applications in software engineering and information systems, computational methods in mathematics and statistics, planning of experiments and simulation techniques. Ignatios Deligiannis is an Associate Professor at Alexander Technological Education Institute of Thessaloniki, Greece. His main interests are Object-Oriented software methods, and in particular design assessment and measurement. He received his B.Sc. in Computer Science from Lund University, Sweden, in 1979, and then worked for several years in software development at Siemens Telecommunications industry. He was member of ESERG (Empirical Software Engineering Research Group at Bournemouth University, UK). Currently, he is a research partner of Software Engineering Group::Plase laboratory, Aristotle University of Thessaloniki, Greece. 相似文献
993.
N. Zaerpour M. Rabbani A. H. Gharehgozli R. Tavakkoli-Moghaddam 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(11):1035-1054
Manufacturing systems produce their products by making use of three main strategies: make-to-order, make-to-stock and hybrid
(combination of MTO and MTS strategies) systems. Hence, several products must be considered and partitioned in terms of many
different conflicting criteria, leading to a large set of subjective or ambiguous data. Thus, an effective evaluation approach
is essential to improve decision quality. In this paper a comprehensive decision, making structure is proposed to choose the
proper strategy for producing the products. It consists of a novel hybrid methodology, which combines analytical hierarchy
process (AHP) and technique for order performance by similarity to ideal solution (TOPSIS) for partitioning of products. In
this study, the rating of each alternative regarding different criteria (throughout the TOPSIS technique) is described by
means of linguistic variables. Furthermore, fuzzy AHP methodology is applied to determine the weights of evaluation criteria.
At the end, the effectiveness of the proposed model is demonstrated through a case study. 相似文献
994.
Control systems designed by the principle of matching gives rise to problems of evaluating the peak output. This paper proposes a practical method for computing the peak output of linear time-invariant and non-anticipative systems for a class of possible sets that are characterized with many bounding conditions on the two- and/or the infinity-norms of the inputs and their derivatives. The original infinite-dimensional convex optimization problem is approximated as a large-scale convex programme defined in a Euclidean space, which are associated with sparse matrices and thus can be solved efficiently in practice. The numerical results show that the method performs satisfactorily, and that using a possible set with many bounding conditions can help to reduce the design conservatism and thereby yield a better match. 相似文献
995.
A global sliding‐mode control (GSMC) scheme is proposed to provide a framework for ensuring the existence of a sliding mode throughout an entire response. Based on this framework, robust eigenvalue‐assignment GSMC (REA‐GSMC) is proposed to robustly assign closed‐loop eigenvalues that must be real. The eigenvalues being all real, however, leads to sluggish responses. According to most error criteria such as IAE, ISE, and ITAE, the optimum system should have complex eigenvalues. This paper proposes a GSMC scheme with generalized sliding dynamics, referred to as Generalized GSMC, in order to release the previous constraint on the REA‐GSMC. Thus, the Generalized GSMC can be designed to achieve a system that is both robust and optimum in the sense that it minimizes certain error performance indices in spite of the presence of system uncertainties. Experiments were conducted on a two‐link direct‐drive manipulator to demonstrate the effectiveness of the proposed scheme. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
996.
战争海报作为战争时期重要的宣传手段之一,是特殊时期的特殊产物,设计手法亦呈多样化,本文从现代设计视觉回望,阐述其背景和现状,分析战争海报价值及其设计元素组成和艺术特征。 相似文献
997.
白杨 《数码设计:surface》2009,(12):150-152
手工绘图时期非常注重各种绘图工具的学习,计算机的出现使得手工绘图工具对效果图的渲染变的不再重要。要想画好效果图,提高人脑的认识才是关键。本文从实践设计总结的经验出发,提出效果图渲染的学习,从认识上可以分为"全因素表现"和"快速表现";进一步又阐述了每种渲染在设计师的头脑认识上需要把握哪好些处理内容。 相似文献
998.
本文介绍了设计素描的概念和研究要素,指出设计素描中材质感的表现形式——线和明暗,并从时装面料和服饰配件两方面阐述了线和明暗在时装画中的应用,为我们认识、理解和感悟设计素描在服装设计中的作用提供了切入点。 相似文献
999.
Linear control of a boiler–turbine unit is discussed in this paper. Based on the nonlinear model of the unit, this paper analyzes the nonlinearity of the unit, and selects the appropriate operating points so that the linear controller can achieve wide-range performance. Simulation and experimental results at the No. 4 Unit at the Dalate Power Plant show that the linear controller can achieve the desired performance under a specific range of load variations. 相似文献
1000.
Matthew O.T. Cole Author Vitae Theeraphong Wongratanaphisan Author Vitae 《Automatica》2008,44(11):2876-2883
Model-based feedback control of vibration in flexible structures can be complicated by the possibility that interaction with an external body occurs. If not accounted for, instability or poor performance may result. In this paper, a method is proposed for achieving robust vibration control of flexible structures under contact. The method uses robust linear state feedback, coupled with a state estimation scheme utilizing contact force measurement. Uncertain contact characteristics are modelled by a sector-bounded non-linear function, such that state feedback gains can be synthesized using a matrix inequality formulation of the Popov stability criterion. A separation theorem is used to establish a robust H2 cost bound for the closed loop system. Experimental results from a multi-mode flexible structure testbed confirm that vibration attenuation and stability can be maintained over a broad range of contact characteristics, in terms of compliance and clearance. 相似文献