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21.
为保证自组织容迟网络能够可靠并有效传输数据,以更好地实现在传输效率与网络开销之间的均衡,提出了一种基于分布传感的容迟自组织网络动态融合机制.该机制在分析自组织容迟网节点分布特性的基础上,通过分布式节点密度感知,实现快速获知整个网络中热点区域的节点分布,并利用热点区域节点之间的限跳函数实现动态路由,以最大程度减少在热点区域的冗余数据,有效地降低网络整体传输时延与开销.仿真结果表明,该算法在传输效率和时延方面展示具有明显优势,且有效降低网络冗余信息开销.  相似文献   
22.
To improve the path slack of Field Programmable Gate Array (FPGA), this paper proposes a timing slack optimization approach which utilizes the hybrid routing strategy of rip-up-retry and pathfinder. Firstly, effect of process variations on path slack is analyzed, and by constructing a col- location table of delay model that takes into account the multi-corner process, the complex statistical static timing analysis is successfully translated into a simple classical static timing analysis. Then, based on the hybrid routing strategy of rip-up-retry and pathfinder, by adjusting the critical path which detours a long distance, the critical path delay is reduced and the path slack is optimized. Experimental results show that, using the hybrid routing strategy, the number of paths with negative slack can be optimized (reduced) by 85.8% on average compared with the Versatile Place and Route (VPR) tim- ing-driven routing algorithm, while the run-time is only increased by 15.02% on average.  相似文献   
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针对战场信息的不确定性和不完整性的问题,建立基于灰色局势决策法的炮兵火力方案优选模型。该模型运用灰色理论,客观全面地反映每个火力方案在每个对策下的特征,并对各火力方案的优劣进行排序。实例分析证明:该方法为炮兵指挥员选择火力方案提供了一种高效、科学的辅助决策方法。  相似文献   
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介绍了电话交换网络发生话务拥塞的原因及作为NEAX61交换系统维护人员对NEAX61交换网话务络拥塞的预防和控制,对几种话务拥塞的处理方法进行了举例说明。  相似文献   
27.
本文主要研究在WDM全光通信网中,将业务等级约定(SLA)和路由波长分配(RWA)问题结合在一起考虑,根据实际网络情况,确保高等级业务得到更好的服务。本文从不同的角度考虑,提出了两种算法,并对其进行了仿真比较和分析。  相似文献   
28.
首先提出了一种新的融合AdHoe和蜂窝网络体系结构。接着在这种融合网络结构下,对传统AODV路由协议进行了改进,设计了一种蜂窝辅助的AODV路由协议(CA-AODV)。CA-AODV路由协议利用蜂窝系统中代理节点所保存的移动adhoe节点位置信息,来维护、更新节点中的路由,这种主动维护路由信息的方法从而可以提高传统AODV协议的性能。最后文中通过NS-2仿真表明:在数据发送率较高的情况下,CA-AODV路由协议能显著提高传统AODV协议的系统参数性能。  相似文献   
29.
Multiconstrained QoS multipath routing in wireless sensor networks   总被引:2,自引:0,他引:2  
Sensor nodes are densely deployed to accomplish various applications because of the inexpensive cost and small size. Depending on different applications, the traffic in the wireless sensor networks may be mixed with time-sensitive packets and reliability-demanding packets. Therefore, QoS routing is an important issue in wireless sensor networks. Our goal is to provide soft-QoS to different packets as path information is not readily available in wireless networks. In this paper, we utilize the multiple paths between the source and sink pairs for QoS provisioning. Unlike E2E QoS schemes, soft-QoS mapped into links on a path is provided based on local link state information. By the estimation and approximation of path quality, traditional NP-complete QoS problem can be transformed to a modest problem. The idea is to formulate the optimization problem as a probabilistic programming, then based on some approximation technique, we convert it into a deterministic linear programming, which is much easier and convenient to solve. More importantly, the resulting solution is also one to the original probabilistic programming. Simulation results demonstrate the effectiveness of our approach. This work was supported in part by the U.S. National Science Foundation under grant DBI-0529012, the National Science Foundation Faculty Early Career Development Award under grant ANI-0093241 and the Office of Naval Research under Young Investigator Award N000140210464. Xiaoxia Huang received her BS and MS in the Electrical Engineering from Huazhong University of Science and Technology in 2000 and 2002, respectively. She is completing her Ph.D. degree in the Department of Electrical and Computer Engineering at the University of Florida. Her research interests include mobile computing, QoS and routing in wireless ad hoc networks and wireless sensor networks. Yuguang Fang received a Ph.D. degree in Systems Engineering from Case Western Reserve University in January 1994 and a Ph.D degree in Electrical Engineering from Boston University in May 1997. He was an assistant professor in the Department of Electrical and Computer Engineering at New Jersey Institute of Technology from July 1998 to May 2000. He then joined the Department of Electrical and Computer Engineering at University of Florida in May 2000 as an assistant professor, got an early promotion to an associate professor with tenure in August 2003 and to a full professor in August 2005. He holds a University of Florida Research Foundation (UFRF) Professorship from 2006 to 2009. He has published over 200 papers in refereed professional journals and conferences. He received the National Science Foundation Faculty Early Career Award in 2001 and the Office of Naval Research Young Investigator Award in 2002. He has served on several editorial boards of technical journals including IEEE Transactions on Communications, IEEE Transactions on Wireless Communications, IEEE Transactions on Mobile Computing and ACM Wireless Networks. He have also been activitely participating in professional conference organizations such as serving as The Steering Committee Co-Chair for QShine, the Technical Program Vice-Chair for IEEE INFOCOM’2005, Technical Program Symposium Co-Chair for IEEE Globecom’2004, and a member of Technical Program Committee for IEEE INFOCOM (1998, 2000, 2003–2007).  相似文献   
30.
采用谱体积(SV)方法划分计算域,研究了双曲型守恒律的高精度差分格式;引入牛顿数值差商,重构小区间交界面上的正、负数值通量,并给出了校正公式;对时间离散采取高阶Runge-Kutta TVD方法,构造了三维非线性双曲型守恒律方程的一个高精度、高分辨率的守恒型差分格式,证明了格式的MmB特性。数值模拟计算结果表明了MmB差分格式的有效性。  相似文献   
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