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991.
张雁 《徐州工程学院学报》2003,(5)
混凝土冬期施工管理中主要存在除冻剂的使用及质量控制、混凝土强度等级、测温工作、受冻临界强度检验等方面问题。文章结合工程质量检验实际情况,进行了具体分析。 相似文献
992.
SABUL: A Transport Protocol for Grid Computing 总被引:5,自引:0,他引:5
This paper describes SABUL, an application-level data transfer protocol for data-intensive applications over high bandwidth-delay product networks. SABUL is designed for reliability, high performance, fairness and stability. It uses UDP to transfer data and TCP to return control messages. A rate-based congestion control that tunes the inter-packet transmission time helps achieve both efficiency and fairness. In order to remove the fairness bias between flows with different network delays, SABUL adjusts its sending rate at uniform intervals, instead of at intervals determined by round trip time. This protocol has demonstrated its efficiency and fairness in both experimental and practical applications. SABUL has been implemented as an open source C++ library, which has been successfully used in several Grid computing applications. 相似文献
993.
994.
首先描述了当前我国电信市场上价格大战的种种现象,剖析了价格战对固网市场产生的强烈影响和冲击。指出应对价格战急需政府加强监管力度,最后提出了政府加强监管的政策性建议。 相似文献
995.
A dual neural network for redundancy resolution of kinematically redundant manipulators subject to joint limits and joint velocity limits 总被引:4,自引:0,他引:4
Yunong Zhang Jun Wang Youshen Xia 《Neural Networks, IEEE Transactions on》2003,14(3):658-667
In this paper, a recurrent neural network called the dual neural network is proposed for online redundancy resolution of kinematically redundant manipulators. Physical constraints such as joint limits and joint velocity limits, together with the drift-free criterion as a secondary task, are incorporated into the problem formulation of redundancy resolution. Compared to other recurrent neural networks, the dual neural network is piecewise linear and has much simpler architecture with only one layer of neurons. The dual neural network is shown to be globally (exponentially) convergent to optimal solutions. The dual neural network is simulated to control the PA10 robot manipulator with effectiveness demonstrated. 相似文献
996.
Synthesizing high-frequency rules from different data sources 总被引:10,自引:0,他引:10
Many large organizations have multiple data sources, such as different branches of an interstate company. While putting all data together from different sources might amass a huge database for centralized processing, mining association rules at different data sources and forwarding the rules (rather than the original raw data) to the centralized company headquarter provides a feasible way to deal with multiple data source problems. In the meanwhile, the association rules at each data source may be required for that data source in the first instance, so association analysis at each data source is also important and useful. However, the forwarded rules from different data sources may be too many for the centralized company headquarter to use. This paper presents a weighting model for synthesizing high-frequency association rules from different data sources. There are two reasons to focus on high-frequency rules. First, a centralized company headquarter is interested in high-frequency rules because they are supported by most of its branches for corporate profitability. Second, high-frequency rules have larger chances to become valid rules in the union of all data sources. In order to extract high-frequency rules efficiently, a procedure of rule selection is also constructed to enhance the weighting model by coping with low-frequency rules. Experimental results show that our proposed weighting model is efficient and effective. 相似文献
997.
This paper presents a hierarchical flight control system for unmanned aerial vehicles. The proposed system executes high-level mission objectives by progressively substantiating them into machine-level commands. The acquired information from various sensors is propagated back to the higher layers for reactive decision making. Each vehicle is connected via standardized wireless communication protocol for scalable multi-agent coordination. The proposed system has been successfully implemented on a number of small helicopters and validated in various applications. Results from waypoint navigation, a probabilistic pursuit-evasion game and vision-based target tracking demonstrate the potential of the proposed approach toward intelligent flying robots. 相似文献
998.
999.
WinSock技术在水厂远程监控系统中的应用 总被引:3,自引:0,他引:3
主要讨论了WinSock技术的两种套接字形式:数据报套接字和流式套接字。分析了两者各自的技术特点以及在水厂远程监控系统中具体应用。借助WinSock技术,实现了水厂的远程监控。 相似文献
1000.
土壤样品的微波消解及其痕量铀的分析 总被引:3,自引:1,他引:3
对3个土壤样和2个放射性河床沉积物的国家标准物质进行了微波消解,又采用TOPO萃取和液体荧光法分析了样品中的铀含量,并将分析结果与国家标准方法GB11220.2-89的分析结果进行了比较。结果表明,微波消解法与国家标准方法一样,均不能实现土壤的全部消解,但与国家标准方法相比较,微波消解速度快,所需试剂量少,且易于实现定量控制,铀回收率高,分析精度高。对不溶物进行X射线能谱分析发现,其主要组成为铝、钛及过渡金属的氟化物或氧化物。同位素质谱分析表明,国家标准物质GBW08304中的^234U,^235U均比天然丰度低,另一个国家标准物质GBW08304a中铀的同位素分布与天然组成基本一致。 相似文献