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1.
空调器用盘式电机的计算机模拟 总被引:1,自引:0,他引:1
介绍线绕盘式永磁直流电流电动机的结构特点,设计原则和有关的主要设计公式,并进行电机的计算机模拟。模拟运行结果与样机实测数据基本相符。 相似文献
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本文提出一种基于本地缓存的弹性分组环保护倒换机制(WrapProtectionBasedOnLocalBuffers,简称WP-LB)。其主要思想是当环路上任何位于源节点和故障区域之间的中间节点接收到含有故障信息的控制信令后,就不再向下游转发数据分组,而是在本地缓存这些数据。等到保护通路建立好之后,再把缓存的数据分组经过保护通路发送给目的节点。分析计算表明,与原有的保护倒换(WrapProtection,简称WP)机制相比,WP-LB机制不仅提高带宽利用率,减少平均时延,并且还能避免数据包的丢失和失序。 相似文献
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Dynamic Survivability in WDM Mesh Networks Under Dynamic Traffic 总被引:3,自引:0,他引:3
Network survivability is a crucial requirement in WDM mesh networks. In this paper, we systematically consider the problem of dynamic survivability with dynamic single link failure in WDM networks under dynamic traffic demands. Specifically, we investigate various protection schemes, such as dedicated path protection (DPP), shared path protection (SPP), dedicated link protection (DLP), shared link protection (SLP), and two restoration schemes, path restoration (PR) and link restoration (LR). Moreover, two new shared protection methods are proposed, i.e., SRLG-based shared link protection (SRLG-SLP) and SRLG-based shared path protection (SRLG-SPP). The SRLG (shared risk link group) constraint defines the availability of protection resources to a working path, which requires that any two working paths sharing the same risk of failure (or in the same SRLG) cannot share the same protection resources. Furthermore, in our study, we consider a more practical dynamic single-link failure model, in which the link-failure-interarrival time and link-failure-holding time are considered as two independent parameters. Based on this link-failure model, extensive simulations are done to analyze and compare the dynamic survivable performance of various protection and restoration schemes. Resource utilization, protection efficiency, restoration efficiency, and service disruption ratio are employed as survivable performance metrics versus traffic load, link-failure frequency, and link-failure reparation time to evaluate the survivable performance. Many meaningful results are given. In addition, we show that the developed SRLG-SLP and SRLG-SPP protection schemes perform very well in terms of protection efficiency and service disruption ratio, while sacrificing some performance in terms of resource utilization. 相似文献
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Jinhua Huang Qingji Xie Yueming Tan Yingchun Fu Zhaohong Su Yi Huang Shouzhuo Yao 《Materials Chemistry and Physics》2009,118(2-3):371-378
Pt nanoparticles well dispersed on multiwalled carbon nanotubes (MWCNTs) were prepared for high-performance electrocatalytic oxidation of methanol in both acidic and alkaline media via the co-electrodeposition/stripping (CS) protocol, namely, co-electrodeposition of Pt and Cu followed by electrochemical stripping of Cu, as examined by cyclic voltammetry (CV), electrochemical quartz crystal microbalance (EQCM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The Pt catalyst prepared by the CS protocol on MWCNTs (Ptcs/MWCNTs/Au) exhibited a specific electrocatalytic activity of 519 and 2210 A g−1 toward cyclic voltammetric electrooxidation (50 mV s−1) of methanol in 0.5 M CH3OH + 0.5 M H2SO4 and 0.5 M CH3OH + 1.0 M NaOH media, respectively, which are larger than those prepared by conventional electrodeposition from chloroplatinic acid on Au and MWCNTs/Au, as well as that by a CS protocol on Au. The Ptcs/MWCNTs/Au electrode also possessed the highest stability, which maintained 91% and 90% of its initial catalytic activity after 120-cycle CV in 0.5 M CH3OH + 0.5 M H2SO4 and 0.5 M CH3OH + 1.0 M NaOH, respectively. The electrode kinetics of methanol oxidation is also briefly discussed. The nanosubstrate-based CS protocol is simple, convenient and efficient, which is expected to find wide applications in film electrochemistry and electrocatalysis. 相似文献
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矢值序列空间BMC(X)中的序列紧集 总被引:1,自引:0,他引:1
利用局部凸空间理论,讨论了矢值序列空间BMC(X)中的相对序列紧集的性质,给出了其特征刻划,即BMC(X)中的子集是相对序列紧集,当且仅当它是一致收敛集及其每个坐标射影集是相对序列紧集。同时,在局部凸空间X不包含c0的情况下,给出了BMC(X)中的相对序列紧集的另一种特征刻划。 相似文献
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AnalysisandTestonStartingTorqueofLow-speedSynchronousMotorsGUOQingji;GUOHong;CHENGZhi;SONGKai郭庆吉,郭宏,程智,宋凯(Dept.ofElectricalEn... 相似文献