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51.
针对片状颗粒厚度检测的实际需求,结合机器视觉、图像处理和嵌入式技术,设计与实现了一套基于高性能ARM11的微片状颗粒厚度检测系统。该系统以QT和S3C6410为软硬件平台,提出了利用轮廓提取和最小矩形边界框相结合的方法计算片状颗粒厚度。结果表明,该检测系统具有处理速度快,测量精度高和成本低廉等优点,满足了对颗粒厚度测量的需求。 相似文献
52.
传统的基于测量的Internet性能参数估计要求测量点是端到端路径的起点和终点,这一方面使得测量和估计带有很大盲目性,增加了网络流量;另一方面会导致测量方法难于实施,估计结果不准确。提出了基于分段测量的思想,对ITU-T定义的延迟、延迟变化、丢包率和错误率4个参数进行测量和估计。由于测量是分段进行的,每次测量值都可应用于多条端到端路径的性能参数估计,因此降低了盲目性并大大减少了网络流量。为验证本方法的性能,基于PlanetLab平台设计和实现了生成器、性能参数测量机和结果收集器。通过在全球的100多个节点上的部署和为期一个月的运行证明了该方法便于实施,并且具有较高的准确性。 相似文献
53.
54.
为了实现CAD与CAPP系统的有效集成,提出了以切削成形能力模型为基础的加工特征识别方法.通过引入成形函数揭示了切削成形过程的核心要素;据此提出切削模式概念,构建了以切削模式为核心的切削成形能力模型,实现加工表面到加工方法的映射.该模型应用于加工特征识别,为零件表面生成可行的加工方法集合;在此基础上,以提高零件的加工效率为目标建立优化模型,为每一个表面筛选出合适的加工方法,并将同一次装夹下使用同一把刀具加工的表面聚集为一个加工特征,从而实现加工特征的识别.最后通过实例测试验证了文中方法的正确性和有效性.该方法能有效地解决现有特征识别中存在的鲁棒性较差、相交特征识别困难等问题. 相似文献
55.
We introduce a simple, linear time algorithm for recognizing trivially perfect (TP) graphs. It improves upon the algorithm of Yan et al. [J.-H. Yan, J.-J. Chen, G.J. Chang, Quasi-threshold graphs, Discrete Appl. Math. 69 (3) (1996) 247–255] in that it is certifying, producing a P4 or a C4 when the graph is not TP. In addition, our algorithm can be easily modified to recognize the complement of TP graphs (co-TP) in linear time as well. It is based on lexicographic BFS, and in particular the technique of partition refinement, which has been used in the recognition of many other graph classes [D.G. Corneil, Lexicographic breadth first search—a survey, in: WG 2004, in: Lecture Notes in Comput. Sci., vol. 3353, Springer, 2004, pp. 1–19]. 相似文献
56.
57.
Statistical process control (SPC) is a conventional means of monitoring software processes and detecting related problems,
where the causes of detected problems can be identified using causal analysis. Determining the actual causes of reported problems
requires significant effort due to the large number of possible causes. This study presents an approach to detect problems
and identify the causes of problems using multivariate SPC. This proposed method can be applied to monitor multiple measures
of software process simultaneously. The measures which are detected as the major impacts to the out-of-control signals can
be used to identify the causes where the partial least squares (PLS) and statistical hypothesis testing are utilized to validate
the identified causes of problems in this study. The main advantage of the proposed approach is that the correlated indices
can be monitored simultaneously to facilitate the causal analysis of a software process.
Ching-Pao Chang is a PhD candidate in Computer Science & Information Engineering at the National Cheng-Kung University, Taiwan. He received his MA from the University of Southern California in 1998 in Computer Science. His current work deals with the software process improvement and defect prevention using machine learning techniques. Chih-Ping Chu is Professor of Software Engineering in Department of Computer Science & Information Engineering at the National Cheng-Kung University (NCKU) in Taiwan. He received his MA in Computer Science from the University of California, Riverside in 1987, and his Doctorate in Computer Science from Louisiana State University in 1991. He is especially interested in parallel computing and software engineering. 相似文献
Chih-Ping ChuEmail: |
Ching-Pao Chang is a PhD candidate in Computer Science & Information Engineering at the National Cheng-Kung University, Taiwan. He received his MA from the University of Southern California in 1998 in Computer Science. His current work deals with the software process improvement and defect prevention using machine learning techniques. Chih-Ping Chu is Professor of Software Engineering in Department of Computer Science & Information Engineering at the National Cheng-Kung University (NCKU) in Taiwan. He received his MA in Computer Science from the University of California, Riverside in 1987, and his Doctorate in Computer Science from Louisiana State University in 1991. He is especially interested in parallel computing and software engineering. 相似文献
58.
间接竞争ELISA方法用于脱落酸的检测 总被引:1,自引:0,他引:1
该文研制了植物激素脱落酸(ABA)间接竞争酶联免疫试剂盒,该试剂盒可对ABA进行快速检测.文中成功制备了脱落酸和牛血清蛋白的交联物(ABA-BSA),并对交联物的浓度、抗体稀释度、酶标二抗稀释度对实验的影响进行了考察.结果表明,该试剂盒具有高灵敏性,最低检出浓度为1.38 ng/mL,在10ns/mL~1 000 ng/mL之间,吸光度与浓度的对数呈良好的线性关系.样品添加回收率在95.98%~102.25%之间,平均回收率为100.18%,变异系数(CV)在1.27%~4.68%之间,平均变异系数为3.18%. 相似文献
60.
Reliable and Energy-Efficient Routing for Static Wireless Ad Hoc Networks with Unreliable Links 总被引:1,自引:0,他引:1
Li Xiang-Yang Wang Yu Chen Haiming Chu Xiaowen Wu Yanwei Qi Yong 《Parallel and Distributed Systems, IEEE Transactions on》2009,20(10):1408-1421
Energy efficient routing and power control techniques in wireless ad hoc networks have drawn considerable research interests recently. In this paper, we address the problem of energy efficient reliable routing for wireless ad hoc networks in the presence of unreliable communication links or devices or lossy wireless link layers by integrating the power control techniques into the energy efficient routing. We consider both the case when the link layer implements a perfect reliability and the case when the reliability is implemented through the transport layer, e.g., TCP. We study the energy efficient unicast and multicast when the links are unreliable. Subsequently, we study how to perform power control (thus, controlling the reliability of each communication link) such that the unicast routings use the least power when the communication links are unreliable, while the power used by multicast is close to optimum. Extensive simulations have been conducted to study the power consumption, the end-to-end delay, and the network throughput of our proposed protocols compared with existing protocols. 相似文献