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21.
M.C. Lucas-EstañAuthor Vitae J. GozalvezAuthor VitaeJ. Sanchez-SorianoAuthor Vitae 《Computer Networks》2012,56(1):112-126
Wireless systems will be characterized by the coexistence of heterogeneous Radio Access Technologies (RATs) with different, but also complementary, performance and technical characteristics. These heterogeneous wireless networks will provide network operators the possibility to efficiently and coordinately use the heterogeneous radio resources, for which novel Joint Radio Resource Management (JRRM) policies need to be designed. In this context, this work proposes and evaluates a JRRM policy that simultaneously determines for each user an adequate combination of RAT and number of radio resources within such RAT to guarantee the user/service QoS requirements, and efficiently distribute the radio resources considering a user fairness approach aimed at maximizing the system capacity. To this aim, the JRRM algorithm, which takes into account the discrete nature of radio resources, is based on integer linear programming optimization mechanisms. 相似文献
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研究了一种新型简化内氧化工艺,并制备了不同氧源系数的Cu-Al2O3复合材料。用SEM、TEM等分析手段对所制备复合材料烧结态的微观组织进行了研究。结果表明,该简化工艺成功制备了Cu-Al2O3复合材料,在铜基体上弥散分布着大量细小的γ-Al2O3颗粒,其粒径为5~20nm,颗粒间距为25~60nm,当氧源系数(k)为1.20时,压制粉末经烧结(950℃,4h)后全部完成内氧化,此氧化剂含量为最佳的内氧化氧化剂添加量。 相似文献
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Although user experience and personal innovativeness are two important factors in new technology adoption, there has been no prior study to test these factors with the Enterprise Resource Planning (ERP) adoption. This paper investigates moderating roles of user experience on the relationship between the personal innovativeness and the ERP adoption motivations. This issue is important because if the user has more experience with the systems then the power of influence of personal innovativeness on ERP adoption motivation would be different. Thus, this paper tests these important insights of ERP systems adoption with the two different field samples with high (more than three years) and low (less than three years) user experience, based on the innovation diffusion theory, self determination theory, and different types of motivations such as intrinsic and extrinsic motivations. The findings, based on the PLS analysis of the model using 107 ERP end users, show that there are clear moderating effects of user experience—such as impacts of personal innovativeness on ERP systems adoption motivations are higher in case of low user experience samples, as expected. Academic and practical implications are discussed in the paper based on these empirical findings. 相似文献
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The promising potential of cloud computing and its convergence with technologies such as mobile computing, wireless networks, sensor technologies allows for creation and delivery of newer type of cloud services. In this paper, we advocate the use of cloud computing for the creation and management of cloud based health care services. As a representative case study, we design a Cloud Based Intelligent Health Care Service (CBIHCS) that performs real time monitoring of user health data for diagnosis of chronic illness such as diabetes. Advance body sensor components are utilized to gather user specific health data and store in cloud based storage repositories for subsequent analysis and classification. In addition, infrastructure level mechanisms are proposed to provide dynamic resource elasticity for CBIHCS. Experimental results demonstrate that classification accuracy of 92.59% is achieved with our prototype system and the predicted patterns of CPU usage offer better opportunities for adaptive resource elasticity. 相似文献
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《Expert systems with applications》2014,41(13):5804-5816
Cloud computing aims to provide dynamic leasing of server capabilities as scalable virtualized services to end users. However, data centers hosting cloud applications consume vast amounts of electrical energy, thereby contributing to high operational costs and carbon footprints. Green cloud computing solutions that can not only minimize the operational costs but also reduce the environmental impact are necessary. This study focuses on the Infrastructure as a Service model, where custom virtual machines (VMs) are launched in appropriate servers available in a data center. A complete data center resource management scheme is presented in this paper. The scheme can not only ensure user quality of service (through service level agreements) but can also achieve maximum energy saving and green computing goals. Considering that the data center host is usually tens of thousands in size and that using an exact algorithm to solve the resource allocation problem is difficult, the modified shuffled frog leaping algorithm and improved extremal optimization are employed in this study to solve the dynamic allocation problem of VMs. Experimental results demonstrate that the proposed resource management scheme exhibits excellent performance in green cloud computing. 相似文献
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张红霞 《电脑与微电子技术》2014,(16):51-54
《数据结构》精品资源共享课作为服务于高校师生和社会学习者的平台之一,其建设内容主要由基本资源、拓展资源、师生互动组成。在《数据结构》精品资源共享课建设中,明确建设目标,着重进行课程体系及课程资源建设。通过精心组织课程资源,优化师资队伍以及制定科学的课程管理办法等措施,实现资源共享。 相似文献
28.
我国耐火材料矿物资源状况与发展问题的讨论 总被引:2,自引:1,他引:2
介绍了我国耐火资源的现状和开发利用状况,包括我国耐火资源储量分析、耐火资源的行业配置、耐火矿物资源消耗状况以及耐火矿物资源利用情况。对合理利用耐火资源,走可持续发展道路提出建议;通过改进原料产品生产工艺,提高耐火矿物资源的利用效能;合理使用耐火材料,降低耐火资源的消耗。 相似文献
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