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排序方式: 共有191条查询结果,搜索用时 31 毫秒
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We abstract the bus transport networks (BTNs) to two kinds of complex networks with space L and space P methods respectively. Using improved community detecting algorithm (PKM agglomerative algorithm), we analyze the community property of two kinds of BTNs graphs. The results show that the BTNs graph described with space L method have obvious community property, but the other kind of BTNs graph described with space P method have not. The reason is that the BTNs graph described with space P method have the intense overlapping community property and general community division algorithms can not identify this kind of community structure. To overcome this problem, we propose a novel community structure called N-depth community and present a corresponding community detecting algorithm, which can detect overlapping community. Applying the novel community structure and detecting algorithm to a BTN evolution model described with space P, whose network property agrees well with real BTNs', we get obvious community property. 相似文献
86.
基于CAN/LIN总线的汽车车身网络研究 总被引:1,自引:0,他引:1
针对传统汽车电控单元多采用独立模式控制及系统可靠性不高的缺点,提出利用CAN/LIN总线构造汽车车身网络,阐述了该方案的软硬件实现方法,并通过实验室组网验证了其可行性.研究表明:采用CAN/LIN总线可简化线路、降低成本、提高各微处理器间的通信速度、降低故障率,使信息交换变得安全、迅捷、高效. 相似文献
87.
Transport networks, such as railway networks and airport networks, are a kind of random network with complex topology. Recently, more and more scholars paid attention to various kinds of transport networks and try to explore their inherent characteristics. Here we study the exponential properties of a recently introduced Bus Transport Networks (BTNs) evolution model with random overlapping clique structure, which gives a possible explanation for the observed exponential distribution of the connectivities of some BTNs of three major cities in China. Applying mean-field theory, we analyze the BTNs model and prove that this model has the character of exponential distribution of the connectivities, and develop a method to predict the growth dynamics of the individual vertices, and use this to calculate analytically the connectivity distribution and the exponents. By comparing mean-field based theoretic results with the statistical data of real BTNs, we observe that, as a whole, both of their data show similar character of exponential distribution of the connectivities, and their exponents have same order of magnitude, which show the availability of the analytical result of this paper. 相似文献
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介绍了一种用于石油勘探的井下3维VSP(Vertical Seismic Profile)采集系统设计方案,实验验证该系统达到了可测量动态范围80 dB(可测量最大值与最小之比),系统采集、处理和传输的总延时低于200 ms(2 kbit/s采样率)的指标,适用于井下VSP采集.系统采用六级光纤加速度传感器组成阵列,其中每级传感器由三个麦克尔逊干涉仪构成.使用高速DSP处理芯片实现相位产生载波(Phase Generated Carrier,PGC)解调等算法以获得地震波信号;同时应用多个ARM处理器设计光纤检波器阵列控制器以及阵列内部总线. 相似文献
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温度变化是影响纳米干涉仪的一个重要的因素。介绍了一种精密的温度控制仪器 ,它以DS162 4为温度传感器 ,利用单片机AT89C5 2进行数据的采集、传送、温度的控制 ,利用数字式电位器实现低成本的模拟量控制方案。标定后可以实现 0 .0 5℃测量精度。这种温度控制仪具有RS2 3 2通用接口 ,能够与上位计算机相连 ,实现温度的长时间测量和远程温度控制 ,利用PC机的计算能力得出被控系统的模型参数。实验表明在 0 .5h内 ,干涉仪达到热平衡 ,温度变化小于 0 .0 5℃。 相似文献
90.
Atsushi Okamoto Hisashi Matsuoka Motoki Saito Yoshihisa Takayama Mototsugu Takamura 《Optical Review》1999,6(3):189-195
We propose a new optical network device photorefractive connection module (PRCM) which operates as optical switch, amplifier and signal distributor controlled by parallel optical signals. Simple optical control bus systems can be realized by cascade connection of PRCMs. PRCM branches off a desired channel from the spatial multiplexed optical bus line by appropriate setting of the control beam pattern. PRCM uses cross polarized four wave mixing (CPFWM) with extraordinary polarized writing beams and an ordinary polarized reading beam to achieve a high connection gain to the next PRCM stage. We analyze the phase matching angle of CPFWM in which the optical paths of two pump beams are slightly different. The phase conjugate reflectivity indicating a branching ratio of optical signal is derived and calculated in consideration of the phase mismatching Δk. The optimum pump ratio and the grating vector orientation for the largest phase conjugate reflectivity and signal amplification factor are discussed for optical design of PRCM. Since the measured signal beam power after passing through the BaTiO3 crystal is three or four times higher than its incident power, PRCM has a sufficient connection gain for optical bus and interconnection systems. 相似文献