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121.
随着当前各种类型的传感器不断涌现,将各类不同的传感器组网探测必将是今后的发展趋势,对传感器组网效能的分析自然成为重中之重。然而,当前对该问题的研究尚缺乏合适的网络模型和方法对其进行描述。基于此,构建了传感器网络环模型,并提出求取与该传感器网络相对应的邻接矩阵Perron—Frobenius特征值(PFE)的方法,同时通过算例分析了该传感器网络的组网效能,结果证明该方法结构明晰,简单可行,能较好的反映实际,适用于对各种传感器组网的网络化效能分析。  相似文献   
122.
Apriori算法在学生成绩管理中的应用   总被引:3,自引:0,他引:3  
介绍了关联规则的基本概念及Apriori算法,提出了成绩预警模型,并利用Apriori算法进行了求解。所得到不及格课程之间的关联规则,可以为教师的教学管理及学生学习提供一定的指导和参考。  相似文献   
123.
在磁悬浮球系统中采用PID控制时,动态性能较差,控制效果不理想.为了获得控制效果较好的控制器,根据模糊控制原理,设计磁悬浮模糊控制器.根据PID实时控制中的经验,确定模糊控制器的输入输出变量模糊化范围,建立合理的模糊规则表.在Matlab/Simulink中组建实时控制模块,并分别对磁悬浮球系统在无干扰和有干扰下进行实时控制.对控制效果进行分析讨论,证明模糊控制器具有良好的鲁棒性和在非线性系统控制中的有效性.  相似文献   
124.
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.
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   
125.
Mutation testing has traditionally been used as a defect injection technique to assess the effectiveness of a test suite as represented by a “mutation score.” Recently, mutation testing tools have become more efficient, and industrial usage of mutation analysis is experiencing growth. Mutation analysis entails adding or modifying test cases until the test suite is sufficient to detect as many mutants as possible and the mutation score is satisfactory. The augmented test suite resulting from mutation analysis may reveal latent faults and provides a stronger test suite to detect future errors which might be injected. Software engineers often look for guidance on how to augment their test suite using information provided by line and/or branch coverage tools. As the use of mutation analysis grows, software engineers will want to know how the emerging technique compares with and/or complements coverage analysis for guiding the augmentation of an automated test suite. Additionally, software engineers can benefit from an enhanced understanding of efficient mutation analysis techniques. To address these needs for additional information about mutation analysis, we conducted an empirical study of the use of mutation analysis on two open source projects. Our results indicate that a focused effort on increasing mutation score leads to a corresponding increase in line and branch coverage to the point that line coverage, branch coverage and mutation score reach a maximum but leave some types of code structures uncovered. Mutation analysis guides the creation of additional “common programmer error” tests beyond those written to increase line and branch coverage. We also found that 74% of our chosen set of mutation operators is useful, on average, for producing new tests. The remaining 26% of mutation operators did not produce new test cases because their mutants were immediately detected by the initial test suite, indirectly detected by test suites we added to detect other mutants, or were not able to be detected by any test.
Laurie WilliamsEmail:

Ben Smith   is a second year Ph.D. student in Computer Science at North Carolina State University working as an RA under Dr. Laurie Williams. He received his Bachelor’s degree in Computer Science in May of 2007 and he hopes to receive his doctorate in 2012. He has begun work on developing SQL Coverage Metrics as a predictive measure of the security of a web application. This fall, he will be beginning the doctoral preliminary exam and working as a Testing Manager for the NCSU CSC Senior Design Center: North Carolina State’s capstone course for Computer Science. Finally, he has designed and maintained the websites for the Center for Open Software Engineering and ESEM 2009. Laurie Williams   is an Associate Professor in the Computer Science Department of the College of Engineering at North Carolina State University. She leads the Software Engineering Reasearch group and is also the Director of the North Carolina State University Laboratory for Collaborative System Development and the Center for Open Software Engineering. She is also technical co-director of the Center for Open Software Engineering (COSE) and the area technical director of the Secure Open Systems Initiative (SOSI) at North Carolina State University. Laurie received her Ph.D. in Computer Science from the University of Utah, her MBA from Duke University, and her BS in Industrial Engineering from Lehigh University. She worked for IBM for nine years in Raleigh, NC before returning to academia. Laurie’s research interests include agile software development methodologies and practices, collaborative/pair programming, software reliability and testing, and software engineering for secure systems development.   相似文献   
126.
提出基于Vue和Python的可见光波段虚拟伪装场景概念,重点阐述了不同探测方位、不同天气时段的虚拟伪装场景和动态虚拟伪装场景的创建流程,分析了该方法存在的问题并对下一步的工作进行了展望.基于Vue和Python的虚拟伪装场景在可见光波段伪装效果评估方面具有较好的应用前景和推广价值.  相似文献   
127.
于干  康立山 《计算机应用》2008,28(2):319-321
近年来,越来越多的演化计算研究者对动态优化问题产生了很大的兴趣,并产生了很多解决动态优化问题的方法。提出一种新的动态演化算法,与传统的演化算法有所不同,它是建立在划分网格基础上的,故而称它为网格优化算法。通过测试典型的动态优化问题,并与经典的SOS算法进行比较,证明了算法的有效性。  相似文献   
128.
基于MSP430单片机的智能多功能电流测试仪   总被引:2,自引:0,他引:2  
针对现有电源设备在测试电容和压敏电阻等元件的故障电流时,存在检测精度低、实时性差、电路复杂等问题,设计了一种基于MSP430F449单片机的新型智能多功能电流测试仪。该电流测试仪具有电路简单、灵敏度高、响应时间短、功耗低等特点,有推广应用价值。  相似文献   
129.
基于正负理想点的导弹武器系统作战效能评估   总被引:3,自引:0,他引:3  
讨论了目前导弹武器系统作战效能评估中的几点不足,提出用正负理想点法来评估导弹武器系统的作战效能.首先给出评估模型.其次,通过对具有典型意义的5种空舰导弹武器系统作战效能进行分析,给出应用示例,并对评估效果进行分析,得出结论.  相似文献   
130.
预警有助于及时预防和解决隐患,具有重要的应用价值,受到了广泛的关注。提出了一种新的预警机制,以领域相关的预警知识为基础构建预警系统,重点研究了以实际数据为资源,基于背景领域知识挖掘出预警规则,使得预警系统中的预警知识更丰富、更完备、更具有实际应用价值。将上述研究应用于高校教学教务系统的学生成绩预警,实验结果表明所提出的预警机制和方法是有效的。  相似文献   
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