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介绍了一种基于随机圆检测的改进算法。解决了随机圆检测算法随机采样阶段引入的大量无效累积和验证阶段假设圆之外的边缘点所进行的无效计算的问题,首先对边缘图像进行8邻接连通,3个随机采样点在同一个连通曲线内选择,然后利用圆的性质求得圆的参数,再应用证据收集过程来进一步验证圆的真实性,该验证过程中只考虑假设圆的外切正方形和内接正方形之间的边缘点。实验结果表明,该算法计算量小,对比改进前,检测性能有所提高,且鲁棒性也相应提高,同时能够检测圆弧和有相互重叠的多个圆。 相似文献
104.
“龙腾R2”微处理器模块级验证 总被引:1,自引:1,他引:0
针对"龙腾R2"微处理器验证过程中的存在验证规模大,人力资源不足的问题,采用流水线模型构建随机的指令序列生成器,搭建以功能覆盖率为导向的自动化验证平台;该平台在仿真验证过程中能根据处理器的运行状态及覆盖率实时地调整指令流以侧重当前验证不充分的功能模块,实现自动化验证;通过仿真,与传统方法相比,在达到同等验证程度的情况下,使用该平台验证周期明显缩短,同时验证覆盖率也有所提高。 相似文献
105.
Namgon?Kim JongWon?KimEmail author Thomas?D.?Uram 《Multimedia Tools and Applications》2009,44(1):17-37
In multi-party collaborative environments, a group of users can share multiple media streams via IP multicasting. However,
despite of the efficiency of IP multicast, it is not widely available and alternative application-layer multicast approaches
are introduced. Application-layer multicast is advantageous, however, it incurs additional processing delays. In this paper,
we present a new hybrid-style application-layer multicast solution that satisfies both network efficiency and easy deployment.
We achieve this goal by connecting multicast islands through UDP tunnels employing UMTP (UDP multicast tunneling protocol).
We also design a MPROBE protocol to remove multicast loop among multicast island in real Internet. We verify the feasibility
of the proposed solution by implementing a prototype tool, AG Connector, that works on Access Grid multi-party collaborative
environment.
相似文献
Thomas D. UramEmail: |
106.
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
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109.
汽车Ad-Hoc网络是一种特殊的Ad-Hoc网络,其路由层面临着许多挑战。本文提出汽车Ad-Hoc网络中一种改进的CBF算法--ICBF。通过速度、方向和距离三个重要的因素控制定时器,更准确地选择下一跳转发节点;利用城市场景下汽车与相邻汽车之间速度差较小的特点,减少了数据包的广播;提出一种新的锚点路径选择算法,使得ICBF协议能够主动地感知地理拓扑和交通密度,从而达到优化路由性能的目的。实验表明,在城市场景下,ICBF算法能提高数据转发成功率,减少网络的带宽负荷。 相似文献
110.
为了满足低成本建设5G广覆盖网络的需求,需要提前研究低频3G、4G网络向5G重耕的最佳方案。在没有进行重耕,因而没有理想的低频5G测试环境的情况下,采用理论分析的手段进行重耕后的覆盖能力估算。以未来L900重耕用于5G广覆盖为例,探讨了链路预算的关键设定、模型选择等问题,并通过多个本地网实际测试数据间接验证估算结果的合理性。所得结论已实际应用于某大运营商对全国900 MHz网络的规划方案,对于指导网络重耕具有重要的借鉴意义,也为面向覆盖和感知的6G网络演进及重耕提供了参考模型。 相似文献