428 research outputs found

    Large-eddy simulation of flows past a flapping airfoil using immersed boundary method

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    The numerical simulation of flows past flapping foils at moderate Reynolds numbers presents two challenges to computational fluid dynamics: turbulent flows and moving boundaries. The direct forcing immersed boundary (IB) method has been developed to simulate laminar flows. However, its performance in simulating turbulent flows and transitional flows with moving boundaries has not been fully evaluated. In the present work, we use the IB method to simulate fully developed turbulent channel flows and transitional flows past a stationary/plunging SD7003 airfoil. To suppress the non-physical force oscillations in the plunging case, we use the smoothed discrete delta function for interpolation in the IB method. The results of the present work demonstrate that the IB method can be used to simulate turbulent flows and transitional flows with moving boundaries

    A Theoretical Model and the Empirical Study on Adoption of Telecom Operators ’Electronic Channel

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    随着移动互联网的迅猛发展,企业传统的营销战略正发生着颠覆性的变化,传统的线下销售正逐步被线上线下一体化的营销模式所取代,消费者对企业商品、服务的选择和订购产生了新的要求。在这样的背景下,企业的电子渠道从概念走向了应用,电子渠道也正从最初的银行业覆盖到各行各业。特别值得关注的是,在各大电信运营商的转型战略中,营销的互联网化转型均被作为重要的组成部分并成为评估转型是否成功的重要里程碑,中国联通、中国电信、中国移动纷纷投入巨大的资源建设电子渠道,运营商电子渠道的发展前景吸引了相关业界极大的关注和研究热情,但是其庞大的个人终端用户却没有对此表现出相应的兴趣。相比之下,我国电信运营商电子渠道的建设落后于...With the rapid development of mobile internet, disruptive changes are taking place to enterprise’s traditional marketing strategy. The traditional off-line sales are gradually replaced by the integrated online marketing model and consumers have new requirements for enterprise’s goods, choice and purchase of services. In this context, the enterprise’s electronic channels go to the application from ...学位:管理学博士院系专业:管理学院_企业管理学号:1762010015357

    The Remedy and Protection of Social Rights:in the View of Dual Characters Theory of Fundamental Rights

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    基本权利的救济与保护是现代宪法理论研究的重要组成部分。经历了数百年的发展、完善,传统自由权的救济与保护方式已较为完善。但在基本权利体系中居于重要地位、以需要国家积极作为为基本特征的社会权在此方面却相形见绌。究其原因,一是因为社会权存在和发展的时间较短,实践经验不足;二是因为西方社会信守自由主义和个人主义,对社会权可能带来的国家以此为名干涉个人自由保持高度警惕;三是传统基本权利的救济和保护机制系由传统自由权实效化过程中建立起来的,这套机制无法兼容社会权依靠国家的特质。公民基于社会权会产生宏观上较高而微观上有所差别的预期,而国家在理论上和实践中无法全然实现公民的这种权利预期。于是,产生了社会权救济...Research on remedy and protection of fundamental rights constitutes a very important part of contemporary constitution theory. The remedy and protection of traditional liberty have got great advances in the last hundreds of years. By contrast, the remedy and protection of social rights which are very significant have been incomplete during the past years. There are three reasons for this. First, t...学位:法学硕士院系专业:法学院法律系_宪法学和行政法学学号:1292006115040

    论社会保障权的保障——一种作为“客观法”的思路

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    社会保障权在宪法基本权利体系中居于重要地位,其区别于传统宪法基本权利之处在于其实现需要国家的积极作为。公民基于社会保障权会产生宏观上较高而微观上有所差别的预期,而国家在理论上和实践中无法全然实现公民的这种权利预期。于此,产生了社会保障权救济方式与保护程度的特殊性。基本权利双重性质理论是德国宪法基础理论的重要内容,对基本权利与其实证化具有强大的解释力和建构力,本文拟从基本权利双重性质理论,尤其是基本权利的“客观法“功能为视角,来审视社会保障权的保障问题

    A Study on the Choice and Pricing of the Third-party platform in E-Business Operation

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    第三方平台作为电子商务的基础设施近年来正逐步成为网络经济中的重要组成部分,越来越多的企业和个人通过它来开展业务,其具备良好的发展前景。本文试图站在中间者的角度,就第三方电子商务平台这一特殊的信息商品的定价问题进行理论和实践上的研究,给出相关的策略和模型,并就网站企业和传统企业之间相互选择过程中涉及的对功能、服务的评估以及对成本收益的分析进行了较为深入的探讨。 本文的结构如下: 第一章:阐述作为网站企业运营第三方电子商务平台所遵循的信息经济学规律,如规模经济递增理论、网络外部性等。 第二章:介绍了电子商务平台的几种商务模式,对第三方平台的发展前景进行了展望,并分析了第三方平台运作中的一些要...As an infrastructure of e-business, the third-party platform has been becoming an important portion of internet economy. More and more enterprises and people develop their business through the third-party platform, it has good prospect. The paper tries to offer an indifferent analysis of the pricing problem of the third-party e-business plaftorm, which is a special information commodity,and p...学位:工商管理硕士院系专业:管理学院工商管理教育中心_工商管理硕士(MBA)学号:20001501

    城市促进信息消费对策研究——以厦门市为例

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    文章以厦门市为例,分析了城市促进信息消费的环境,针对厦门市发展信息消费的现状,提出了总体思路并给出了完善信息消费基础设施、促进信息资源开放共享、打造城市信息消费产业链、培育信息消费需求、建立相关保障机制等对策措施

    A Study on the Choice and Pricing of the Third-party platform in E-Business Operation

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    第三方平台作为电子商务的基础设施近年来正逐步成为网络经济中的重要组成部分,越来越多的企业和个人通过它来开展业务,其具备良好的发展前景。本文试图站在中间者的角度,就第三方电子商务平台这一特殊的信息商品的定价问题进行理论和实践上的研究,给出相关的策略和模型,并就网站企业和传统企业之间相互选择过程中涉及的对功能、服务的评估以及对成本收益的分析进行了较为深入的探讨。 本文的结构如下: 第一章:阐述作为网站企业运营第三方电子商务平台所遵循的信息经济学规律,如规模经济递增理论、网络外部性等。 第二章:介绍了电子商务平台的几种商务模式,对第三方平台的发展前景进行了展望,并分析了第三方平台运作中的一些要...As an infrastructure of e-business, the third-party platform has been becoming an important portion of internet economy. More and more enterprises and people develop their business through the third-party platform, it has good prospect. The paper tries to offer an indifferent analysis of the pricing problem of the third-party e-business plaftorm, which is a special information commodity,and p...学位:工商管理硕士院系专业:管理学院工商管理教育中心_工商管理硕士(MBA)学号:20001501

    The Game Analysis of Government Subsidies in Low Carbon Economy

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    随着世界经济的发展,环境问题越来越受到国际社会的关注。低碳经济是缓解矛盾的有效措施,我国政府相继颁布了一些推行低碳经济的相关政策,对低碳企业给予补贴扶持。通过归纳各国促进低碳经济的有效政策,对低碳经济中政府、企业、消费者进行博弈分析,对调研数据进行实证研究,旨在提出低碳经济中政府补贴应该偏重于消费者的观点。With the development of the world economy,the changes of environment attract the attention of international society.Low carbon economy is an effective measure to alleviate contradictions.Chinese government has enacted out some low-carbon economy related policies,such as subsidy for low carbon enterprise.In this paper,I summarize the effective policies to promote low carbon economy formulated by the developed countries;analyze the government,enterprises and consumers in low carbon economy through Game theory;empirically analyze the investigation data;put forward a new comment that government subsidies should focus on the consumers.教育部大学生创新性实验计划;项目编号:XMU20090

    Preliminary study of novel live attenuated varicella-zoster virus of ORF7 knock out mutation (rOka△7) and virulence critical factor of ORF7

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    水痘是一种急性、高传染性的儿童常见呼吸道传播疾病,由水痘-带状疱疹病毒(Varicella-zostervirus,VZV)引起。同时VZV也是导致带状疱疹(HZ)的病原体,具有严重的危害性。现今使用的VZV减毒活疫苗株(vOka)是唯一获WHO批准使用的水痘/带状疱疹疫苗株,然而有研究显示,vOka为混合毒株且仍具备感染和潜伏神经系统的能力,可能存在较复杂的安全性隐患。因此,迫切需要发展新型的可消除长期隐患的水痘疫苗株,而VZV关键毒力因子的发现和验证是开展该研究的核心基础。本研究在前期发现VZVORF7抗原缺失可影响病毒在体外人皮肤中感染的工作基础上通过建立包括人皮肤、胸腺、背根神经节移植...Varicella is an acute, high contagious viral disease, and the causative agent is Varicella-zoster virus(VZV), VZV is also the causative agent of Herpes zoster(HZ) So,it is a hamful virus.VZV live attenuated vaccine strain (vOka) used nowadays is the only licenced varicella zoster vaccine by WHO. But research shows that this vaccine is a mixed strain remain neurovirulence and the capacity of establ...学位:理学硕士院系专业:生命科学学院生物学系_生物化学与分子生物学学号:2172009115209

    Study on Bimetallic Active Center Catalysts and Kinetics of Ruthenium Catalysts for Ammonia Synthesis

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    合成氨工业是最重要的化学工业之一,世界各国都致力于合成氨工业的发展。钌催化剂由于其高的催化活性及温和的反应条件被誉为“第二代氨合成催化剂”。1992年,以活性碳为载体的钌催化剂在加拿大Ocelot合成氨厂首次实现工业化。但是,在氨合成反应条件下,钌金属容易使活性碳载体发生甲烷化,导致催化剂活性的降低,限制了钌催化剂的大规模工业应用。氧化镁载体是碱性氧化物,且具有很高的比表面积及稳定性。因此,也作为钌基氨合成催化剂的载体受到广泛研究,但是氧化镁负载的钌催化剂的氨合成活性远低于活性碳负载的钌催化剂。因此,制备具有高氨合成活性及稳定性的钌催化剂是合成氨工业的研究重点。但由于钌催化剂成本昂贵、碳载体易...Ammonia synthesis is one of the most important chemical industries in the world, every countries have paid great efforts to develop ammonia synthesis industry. Ruthenium-based catalyst has been named as "The second-generation catalyst for ammonia synthesis", because it has high catalytic activity for ammonia synthesis and can be operated in mild conditions. In 1992, carbon supported ruthenium cata...学位:理学硕士院系专业:化学化工学院化学系_物理化学(含化学物理)学号:20032510
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