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本文针对航天航空等领域综合电子系统在小型化、一体化设计及信息综合利用等方面的需求,提出一种可动态重构的高速串行通信总线(UM-BUS),采用N(≤32)通道并发传输,通信速率可达6.4Gbps,采用总线型拓扑结构,最大通信距离40m,支持最多30个节点直接互连,具有远程存储访问能力,采用命令应答式协议提供QoS与实时性保证;通过并发通道相互冗余与动态重构,在允许50%性能降低的情况下,能够对N/2通道故障动态容错.在UM-BUS总线基础上,本文提出一种新型的"接入式"体系结构模型,在不改变系统逻辑结构的前提下,能够突破机箱结构限制,将逻辑功能分散嵌入到控制测量对象内部,实现功能模块"接入即用",使得综合电子系统一体化设计成为可能. 相似文献
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Liang Xue Bo Yang Jijun Zhao Zhixin Liu Xinping Guan 《Wireless Communications and Mobile Computing》2015,15(5):848-867
Cognitive radio (CR) networks comprise a number of spectrum agile nodes with the capability of spectrum detection. Applying techniques of spectrum sharing in CR networks can achieve the efficient utilization of network resources. Usually, data rates of user sessions are time varied because of the dynamic behaviors of CR networks. It is expected that the occurrence of link outage should be avoided and incorporated into the routing design under conditions of increasingly crowded spectrum. This paper proposes an integral framework, which considers these two correlated schemes (resource reconfiguration and robust routing) simultaneously. For that, the resource reconfiguration scheme is developed for the efficient usage of network resources and aims at reducing the occupancy of licensed bands. The link outage, resulting from random session rate, is confined within an acceptable range by using strategy of virtual ‘network portfolio’. A robust optimization approach is proposed to guarantee reliable data transmission among possible interfering links. Both these two items (resource reconfiguration and robust routing) are formulated in a framework of cross‐layer optimization. The evolutionary process of CR network states is provided in simulations, where the results show that the joint design proposal can achieve the least interferences among different licensed users while realizing robust routing. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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战术互联网的网络重组是在网络节点或通信链路发生故障,或受到安全威胁时,保证网络强壮性的重要手段之一。根据战术互联网特殊的移动网络环境,提出基于作战指挥原则的组织重组方法。仿真实验结果证明了这些方法的有效性。 相似文献
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《Progress in Photovoltaics: Research and Applications》2017,25(2):149-160
Partial shading causes power loss in a photovoltaic module by inducing a power mismatch within the module. This power loss can be significant in building‐applied and building‐integrated photovoltaic installations. Given the often repetitive nature of shade profiles in such applications, we propose to employ non‐reconfigurable or static configurations. We use our simulation tool to precompute static configurations, apply shading scenarios, such as a chimney or tree shade, and make a comparison between the energy yields of different static configurations, which includes that of a conventional module. We then identify the configuration characteristics that consistently yield a higher energy. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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This paper presents a comprehensive mathematical model for integrated cell formation and inventory lot sizing problem. The proposed model seeks to minimize cell formation costs as well as the costs associated with production, while dynamic conditions, alternative routings, machine capacity limitation, operations sequences, cell size constraints, process deterioration, and machine breakdowns are also taken into account. The total cost consists of machine procurement, cell reconfiguration, preventive and corrective repairs, material handling (intra-cell and inter-cell), machine operation, part subcontracting, finished and unfinished parts inventory cost, and defective parts replacement costs. With respect to the multiple products, multiple process plans for each product and multiple routing alternatives for each process plan which are assumed in the proposed model, the model is combinatorial. Moreover, unreliability conditions are considered, because moving from “in-control” state to “out-of-control” state (process deterioration) and machine breakdowns make the model more practical and applicable. To conquer the breakdowns, preventive and corrective actions are adopted. Finally, a Particle Swarm Optimization (PSO)-based meta-heuristic is developed to overcome NP-completeness of the proposed model. 相似文献
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An adaptive algorithm of fine synchronization for intermediate frequency architecture coherent optical orthogonal frequency division multiplexing (CO-OFDM) transmission system is proposed. The whole synchronization procedure is separated into two steps. In the first step, we use an auto-correlation-style algorithm to achieve the coarse symbol synchronization. In the second step, the proposed algorithm is used to achieve the adaptive fine synchronization. The merit of the proposed algorithm is that it can realize fine synchronization under different environments without adjusting the detect-threshold of timing metric in a dynamically reconfiguration network. And also the algorithm can implement in field-programmable gate array (FPGA) or other digital signal processing (DSP) chips easily. In this paper, the CO-OFDM model is analyzed in theory firstly. Secondly, an analysis on the performance of coarse synchronization algorithm used in this paper is made. Finally, the proposed fine synchronization algorithm is introduced in detail. The simulation experiment result demonstrates that the proposed algorithm achieves fine synchronization under different signal noise ratio (SNR) conditions after 6 fiber-spans transmission. 相似文献