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81.
为有效解决ZigBee网络对于内部攻击缺少防范的问题,并兼顾网络性能受制于有限节点能量的不足,文章在RFSN模型的基础上,提出一种基于节点通信行为、历史评价和能量的综合评价模型,进而针对不同攻击行为给出相应的路由选择方案及监测标准。仿真实验表明,该模型比RFSN模型更能快速准确地识别出恶意节点。 相似文献
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1 IntroductionWhenarouterforwardsapacketinconvention alnetworks,itonlyusesfewsystemresources ,forexample,ituseslittlememoryresourcestotem porarilystorethispacketandfewCPUresourcestosearchforwardingrouteandprocessIPoptionpa rameters.Comparedtoconventional… 相似文献
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武传坤 《电子科学学刊(英文版)》1993,(3)
There are many kinds of special relationships between multiple-valued logical func-tions and their variables, and they are difficult to be judged from their expressions. In thispaper, some sufficient and necessary conditions of the independence and statistical independenceof multiple-valued logical functions on their variables are given. Some conditions of algebraicindependence of multiple-valued logical functions on some of their variables and the way to de-generate a function to the greatest extent are proposed, and some applications of these resultsare indicated. All the results are studied by using Chrestenson spectral techniques. 相似文献
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Internally buffered multistage interconnection network architectures have been widely used in parallel computer systems and large switching fabrics. Migration from electrical domain to optical domain has raised the necessity of developing node architectures with optical buffers. Cascaded fibre delay line architectures can be seen as possible realizations of output and shared buffering in a 2 × 2‐switching element. These approaches can be used as buffered node architecture in a Banyan like interconnect. In this paper, we investigate and compare these approaches by using simulation methods. Different performance metrics, such as normalized throughput, average packet delay, packet loss rate and buffer utilization have been used under uniform and non‐uniform traffic models. Results show that the TC‐chain node Banyan network offer an improved normalized throughput and average packet delay performances under both traffic models without disrupting first‐in‐first‐out order of arrivals. The switched delay‐line requires fewer switching elements than TC and TTC architectures but at the cost of high packet delay. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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数控车床的编程教学,对于民营本科独立学院的机械制造实训教学而言,是难度特别大的项目,而编程教学当中,循环指令G71和G73的难度属最大不过。只有恰当、有效地引导学生理解当中的循环轨迹、参数意义,才能使学生在极为有限的时间内完成独立编程、加工的任务。 相似文献
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Lexicalized reordering models are very important components of phrasebased translation systems.By examining the reordering relationships between adjacent phrases,conventional methods learn these models from the word aligned bilingual corpus,while ignoring the effect of the number of adjacent bilingual phrases.In this paper,we propose a method to take the number of adjacent phrases into account for better estimation of reordering models.Instead of just checking whether there is one phrase adjacent to a given phrase,our method firstly uses a compact structure named reordering graph to represent all phrase segmentations of a parallel sentence,then the effect of the adjacent phrase number can be quantified in a forward-backward fashion,and finally incorporated into the estimation of reordering models.Experimental results on the NIST Chinese-English and WMT French-Spanish data sets show that our approach significantly outperforms the baseline method. 相似文献
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方彝立 《宁波大学学报(理工版)》2002,15(2):51-53
引用1984年尹克震提出的“开关函数的反演公式”,采用伪随机序列技术的思想,提出移位寄存器型时序逻辑网络的一种快速设计方法。 相似文献