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81.
资产证券化凭借其独特的交易机制,已经成为发达国家资本市场的主流融资手段,更是全球领域最重要的金融创新之一。它不但为市场机制作用的发挥奠定了基础,而且充分体现了金融市场一体化的客观要求。信息化条件下,资产证券化快速渗透到社会经济领域的各个层面,对经济运行效率能够产生深远的影响。 相似文献
82.
文章从联通运营商WLAN业务发展的现状出发,对WLAN建设过程中存在的问题进行详细的分析和研究,根据原因提出有效的建设策略,并对3G网络的融合进行全面的阐述。 相似文献
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The traditional deployment strategy of static chargers in wireless rechargeable sensor networks (WRSN) covers all the area.The basic idea is to cover all the positions of nodes.A mathematical model of distance between a charger and the farthest node was established,the relationship between the number of nodes and the mathematical expectation of minimum radius of charging was analyzed,and deployment strategy for static chargers was proposed.The method based on the locations of all nodes that need to be charged in the area,used the smallest enclosing circle (SEC) algorithm and finds the optimal location of the charger through Euclidean delivery boy algorithm.It will decrease charging radius,reduce the minimum required transmitted power,thereby saving the average charging energy consumption.The experimental results demonstrated that the less the number locations that the nodes existed,the more energy will be saved. 相似文献
85.
Shuidong Zhang Fang Liu Huaqiao Peang 《Journal of Macromolecular Science: Physics》2015,54(7):836-850
Dialdehyde sweet potato starch (DASS) with various aldehyde contents was prepared and the properties analyzed in terms of solubility, intrinsic viscosity, scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The results demonstrated that when the aldehyede content of DASS was increased from 20% to 95%, the solubility, molecular weight, crystallizability, and thermal stability decreased. Thermoplastic DASS (TPDASS) was prepared by adding glycerol as a plasticizer; the thermal, rheological, hydrophobic, and tensile properties of TPDASS were investigated. The results indicated that, for the same glycerol content, with the increase of aldehyde content, the moisture adsorption decreased, while the shear viscosity, glass transition temperature, and tensile properties of TPDASS increased significantly. The effects were attributed to the introduction of aldehyde groups reducing the hydrogen bonds and decreasing the hydrophility of the starch. Moreover, the aldehyde and hydroxyl groups of DASS favored a semi-acetal formation with higher aldehyde content and cross-linking of DASS occurred with the increase of aldehyde content. In summary, compared to starch, the thermoplastic properties and hydrophobicity of DASS was improved. In the presence of water (10 wt%), the tensile strength of TPDASS with 95% aldehyde content (TPDASS95) moderately decreased, from 16.7 MPa to 14.0 MPa, when the glycerol content increased from 10% to 30%. The TPDASS with improved properties will find their applications in preparing biodegradable plastics. 相似文献
86.
研究基于扩展Leslie投影矩阵的离散尺度结构种群模型的最优收获问题,约束条件包括生态平衡和开发成本等.运用凸优化理论证明了最优收获策略的存在性,导出了最优收获模式,应用模型参数给出了收获比率.结论显示:最优策略具有两阶段结构. 相似文献
87.
Analysis of the Stakeholder Engagement in the Deployment of Renewables and Smart Grid Technologies 下载免费PDF全文
The implementation of higher shares of renewables in a global energy mix has to be accompanied by simultaneous deployment of enabling smart grid technologies (SGTs). This combination will inevitably lead to a revolutionary change in a conventional energy system, particularly, the shifting role of consumers to prosumers. But resistance may arise from such a dramatic shift, since it is associated with high uncertainty in conjunction with increasing responsibilities of all stakeholders, the urgent need of effective control, and the development of a process. To ensure the positive influence, coherent actions of all players, and appropriate treatment of the spots of resistance, the analysis of the interplay between key stakeholders has been done. The paper introduces the framework for stakeholders' analysis, applies it on the European Union (EU) example, and provides recommendations to reduce the resistance of SGTs deployment. 相似文献
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随着计算机信息技术的飞速发展,云计算技术在互联网领域得到了十分广泛的应用,云计算环境下的网络安全问题也到人们的关注。本文根据笔者对网络安全问题的理解,探讨了云计算环境下的网络安全策略。 相似文献
90.
随着医院信息化建设步伐的逐渐加快,HIS、LIS以及PACS等信息管理系统在医院内部各个科室的业务开展和管理中得到了非常广泛的应用。医院的信息化管理程度也在逐步深化,从而让医院内部各项业务对于信息化的依赖程度越来越高。医院信息系统的安全和稳定在很大程度上决定了医院内部各项业务是否可以正常开展,因此我们必须要做好这项工作。本文结合笔者实际工作经验,就医院信息系统(HIS)的安全管理策略提出了几点建议。 相似文献