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991.
In commercial networks, user nodes operating on batteries are assumed to be selfish to consume their resources (i.e., bandwidth and power) solely maximizing their own benefits (e.g., the received signal-to-noise ratios (SNRs) and datarates). In this paper, a cooperative game theoretical framework is proposed to jointly perform the bandwidth and power allocation for selfish cooperative relay networks. To ensure a fair and efficient resource sharing between two selfish user nodes, we assume that either node can act as a source as well as a potential relay for each other and either node is willing to seek cooperative relaying only if the datarate achieved through cooperation is not lower than that achieved through noncooperation (i.e., direct transmission) by consuming the same amount of bandwidth and power resource. Define the cooperative strategy of a node as the number of bandwidth and power that it is willing to contribute for relaying purpose. The two node joint bandwidth and power allocation (JBPA) problem can then be formulated as a cooperative game. Since the Nash bargaining solution (NBS) to the JBPA game (JBPAG) is computationally difficult to obtain, we divide it into two subgames, i.e., the bandwidth allocation game (BAG) and the power allocation game (PAG). We prove that both the subgames have unique NBS. And then the suboptimal NBS to the JBPAG can be achieved by solving the BAG and PAG sequentially. Simulation results show that the proposed cooperative game scheme is efficient in that the performance loss of the NBS result to that of the maximal overall data-rate scheme is small while the maximal-rate scheme is unfair. The simulation results also show that the NBS result is fair in that both nodes could experience better performance than they work independently and the degree of cooperation of a node only depends on how much contribution its partner can make to improve its own performance. 相似文献
992.
994.
基于身份管理和服务的相结合对网络中的统一身份管理服务进行分析。通过介绍组成身份管理模型的关键定义,提出统一身份服务模型图,再综合网络空间中物联网的技术框架和移动互联网的网络结构,分别提出适用物联网和移动互联网的统一身份服务模型。 相似文献
995.
针对图像中棒材存在粘连,从而造成误计数的问题,研究了一种基于数学形态学的棒材自动计数方案,以实现对棒材实时、精确的计数.该方案针对棒材类计数无需考虑被测物体截面真实形状的特点,将每根棒材处理成单个像素,避免了粘连对计数的影响.为有效克服光照、噪声的干扰以及棒材快速运动造成的图像模糊,该方案首先对采集到的原始棒材图像进行预处理,然后采用腐蚀、细化算法初步实现了棒材粘连的分离,最后采用收缩与检测直线端点算法,实现了单个像素点与原始图像棒材的一一对应,为后续计数奠定了基础.实验证明,该方法不仅能够保证棒材自动计数的精度,并且为棒材定支数包装创造了条件. 相似文献
996.
Various molecular docking software packages are available for modeling interactions between small molecules and proteins.However,there have been few reports of modeling the interactions between metal ions and metalloproteins.In this study,the AutoDock package was employed to example docking into a di-iron binding protein,bacterioferritin.Each binding site of this protein was tested for docking with iron ions.Blind docking experiments showed that all docking conformations converged into two clusters,one for internal iron binding in sites within the metalloprotein and the other for external iron binding on the protein surface.Local docking experiments showed that there were significant differences between two internal iron binding sites.Docking at one site gave a reasonable root-mean-square deviation(RMSD) distribution with relatively low binding energy.Analysis of the binding mode quality for this site revealed that more than half of the docking conformations were categorized as having good binding geometry,while no good conformations were found for the other site.Further investigations indicated that coordinating water molecules contributed to the stability of binding geometries.This study provides an empirical approach towards the study of molecular docking in metalloproteins. 相似文献
997.
998.
挤压边墙技术在混凝土面板堆石坝上游坡面施工中有很大优势,文中介绍了挤压边墙的优点,并对其施工质量控制作了进一步的阐述,以促使该技术在混凝土面板堆石坝中推广应用。 相似文献
999.
全断面隧道掘进机(TBM)因其独特优越的技术性能,广泛应用于长隧道掘进中,为克服其自身的不足,避免产生施工缺陷,本文就TBM设备选型、隧洞设计规划方面需要注意解决的相关问题,进行了研究探讨。 相似文献
1000.
龙口地形条件适宜布置坝体泄流,考虑到龙口泄流同时还要兼顾冲沙和排污,因此泄水建筑物以底孔为主,并设有表孔以排污。底、表孔均为底流消能,通过计算及水工模型试验多方案比较,最终确定采用两级消力池。因为黄河泥沙含量大,硬度高,所以在底、表孔及消能工的过流表面采用抗冲磨混凝土,以提高建筑物的抗冲磨能力。 相似文献