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1.
This paper sketches the contours of the evolving international/monetary system and examines the various roles of the intemediation mechanisms. Then it examines the extent to which the financial system is independent from the “real economy” and the various ways in which it impacts it. The paper discusses some views in good currency on the dynamics of the technology-trade-finance nexus and shows how the financial system influences organization, location and technology choices in meso-innovation systems. The final section of the paper looks at the policy implications that might be derived from the analysis and suggests some directions for the future research. 相似文献
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贾花萍 《计算机与数字工程》2012,40(7):67-68,101
将生物体免疫系统的原理、规则和机制运用到计算机木马检测系统中。利用人工免疫系统的分布性、自适应性、记忆性和高效性,降低检测系统的误报率和提高自适应性问题。 相似文献
4.
Yiping ChenAuthor Vitae Zhe LiAuthor VitaeYaning LiuAuthor Vitae Gwendal SimonAuthor Vitae 《Computer Networks》2012,56(1):365-377
IPTV systems attracting millions of users are now commonly deployed on peer-to-peer (P2P) infrastructures and provide an appealing alternative to multicast-based systems. Typically, a P2P overlay network is associated with each channel, composed of users who receive, watch and redistribute this channel. Yet, channel surfing (aka as zapping) involves switching overlays and may introduce delays, potentially hurting the user experience when compared to multicast-based IPTV. In this paper, we present a distributed system called OAZE (Overlay Augmentation for Zapping Experience) which speeds up the switching process and reduces the overall cross-domain traffic generated by the IPTV system. In OAZE, each peer maintains connections to other peers, not only in a given channel, but also in a subset of all channels to which the associated user is likely to zap. More specifically, we focus on the channel assignment problem, i.e. determining, in a given P2P overlay, the optimal distribution of the responsibility to maintain contact peers to other channels. We propose an approximate algorithm providing guaranteed performances, and a simpler and more practical one. Our experimental results show that OAZE leads to substantial improvements on the connections between peers, resulting in less switching delay and lower network cost; it then represents an appealing add-on for existing P2P IPTV systems. 相似文献
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In the present paper, we investigate the output-controllability and optimal output control problems of a state-dependent switched Boolean control network. By using the semi-tensor product, the algebraic form of the system is obtained. Then, output-controllability problems of the system are discussed and some necessary and sufficient conditions are given. Next, the Mayer-type optimal output control issue is considered and an algorithm is provided to find out the control sequence. At last, an example is given to show the effectiveness of the main results. 相似文献
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Xin Xu Xiaolong ZhangAuthor VitaeHaidong FuAuthor Vitae Li ChenAuthor VitaeHong ZhangAuthor Vitae Xiaowei FuAuthor Vitae 《Computers & Electrical Engineering》2014
A robust autofocus system is a ubiquitous function in today’s mobile phone camera applications. However, due to the power consumption and size requirements, it is difficult for the autofocus function to be implemented into the design of mobile phone cameras. This paper presents a passive autofocus system with low computational complexity. This system uses a novel contrast measurement to determine degree of image sharpness, which can better reflect the information about image discontinuities. In order to gauge the performance of this measurement, a modified peak search strategy is used in the experiments. The experimental results from several typical image sequences validate the effectiveness of the proposed method. 相似文献
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The corrosion of materials in combustion chamber of yellow phosphor tall gas was investrgated. The results reveal that the corrosion behavior is different for different materials under actual work conditions. 相似文献
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国网特高压换流站在运变压器油中溶解气体采用国内市场主流技术,为气象色谱型多组分定性分析技术,占在运特高压换流站93%,光声光谱技术占7%。从故障率和运维成本来看,河南中分、宁波理工等国产设备占据很大优势。此文同时对光声光谱技术进行了分析,提出了其在特高压直流工程的应用前景。 相似文献
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利用已有的地热地质成果,以驻马店—淮滨凹陷带(驻马店—遂平段)地热田为研究区,采用物探和地球化学调查等方法,研究区域地热资源赋存规律,为地热资源保护与综合开发利用提供依据.通过测定同位素氘、氚、14C、18O可知,地热田地热流体年龄为2.6万~3.0万a,地热田及区域地热流体补给来源于驻马店市西部山前地带;依据地热田地质条件,采用热储法和回收率法进行了地热资源储量和地热流体可采资源储量的计算与评价.结果可知:驻马店—遂平一带地热区热储量为2.14×1019J;地热流体可开采量为1.14×107m3/a;地热田地热流体属理疗热矿水,可用于理疗、洗浴. 相似文献