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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.
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
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
65.
基于奇异值分解的机器人工具坐标系标定 总被引:1,自引:0,他引:1
机器人通过在末端安装不同的操作工具来完成各种作业任务,而工具参数的准确度直接影响着机器人操作精度,因此研究一种准确、快速的工具坐标系标定方法具有重要的意义。该文提出一种称为三点五步法的机器人工具坐标系标定方法,并基于矩阵的奇异值分解理论对该标定方法进行了严密的数学推理,证明该标定方法理论上的可行性。采用该算法进行工具坐标系标定具有操作简单、标定精度高、可靠性强和算法易于程序实现的特点。 相似文献
66.
在Web应用系统中经常会遇到文本处理的问题,如何在企业的Web管理系统中应用Word文档是系统用户关心的问题。通过在对Word对象的内容与格式及图表对象进行控制,提出了一种动态实现Word报告生成与下栽的方法。 相似文献
67.
Sravan Kumar Josyula 《Materials and Manufacturing Processes》2017,32(15):1764-1774
The current research work makes an attempt to develop a methodology in order to produce high-quality Al-TiCp composites by using systemized inert atmospheric stir casting facility. The quality of produced composites was characterized using microstructural, Energy-dispersive X-ray spectroscopy (EDX), and machinability studies. Atomized-Cryogenic-Liquid (ACL) spray machining technique was developed and used to enhance the machinability of composite. The results of microstructural analysis reveal that TiCp refines Al grain structure to 50 times lesser than non-reinforced Al grains along the full length of the casting. Energy-dispersive X-ray analysis confirms that no metallic reaction takes place. Machining studies reveal that atomized cryogenic liquid-spray machining significantly improves the quality of machined surface and reduces the progressive wear occurring on tool during turning of Al-TiCp composites in comparison with cryogenically chilled argon, wet, and dry machining conditions, respectively. The scientific methodology highlighted in this study helps to improve the productivity and reduces the manufacturing cost in various industrial applications. 相似文献
68.
Atilla Savaş 《中国工程学刊》2016,39(2):211-220
This paper describes the application of the CFD code, Comsol Multiphysics, to modeling the 3-D metal flow in friction stir welding of AA 2024-T3 aluminum alloy in order to investigate the influence of tool shape over the metal flow. Heat transfer and non-Newtonian flow equations were solved simultaneously. The results from the benchmark experiments found in the literature were used for validation purposes. Scrolled shoulders and threaded pins were given as kinematic boundary conditions. This made the computational problem an easy one. A welding engineer can predict the metal flow around the tool with different scrolls and threads under any welding conditions without making expensive experiments. Investigation of the velocity field before actual welding can save a lot of engineering hours. 相似文献
69.
Chongzhen Du Chuanzhen Huang Shijie Li Hanlian Liu 《Advanced Engineering Materials》2023,25(20):2300564
The design of the lamination structure based on bionic shell pearl layer is a successful method for toughening ceramics. Lamination with strong bonding interfaces is used to improve the mechanical property and low fracture toughness of ceramic cutting tools. Based on the idea of demand–design–preparation–analysis–failure, the development and research progress of laminated ceramic tools are reviewed herein. The research status of design, interlayer diffusion reaction, residual stress, toughening mechanism, and crack propagation path of the biomimetic laminated ceramic composite tool materials is mainly introduced. The major topics of current research include the creation of material systems, the evolution of microstructure, and the assessment of macroscopic mechanical properties. The entire mechanical properties of laminated ceramic tools are significantly influenced by the multicomposition design of the ceramic material system and the optimization design of structural parameters of layer number and layer thickness ratio. However, the research on the practical cutting application of laminated ceramic tools is limited. Cutting tool wear characteristics vary between laminated and homogeneous ceramic tools. The development of useful laminated ceramic cutting tools can greatly benefit from the study on failure mechanisms of laminated ceramic tools. 相似文献
70.
Arguments are presented for the necessity of integrating diagnostics and supervision in technological machines. An example of integrated diagnostics and supervision of the machine tool main drive, based on an expert system and neural network, is shown. Problems of intelligent thermal displacement supervision and questions related to practical supervision of machining centres are presented. 相似文献