660 research outputs found

    The systematic modeling and performance optimization of the integrated solid oxide fuel cell-gas turbine and organic Rankine cycle combined power system

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    中国是世界最大的能源消费国,占全球消费总量的23%,但能源综合利用效率普遍较低。据统计,美国的能源效率高达60%,欧洲超过60%,其它发达国家的平均水平为50%,而中国仅为33%[1]。另一方面,中国单位GDP的能耗是世界平均水平的3.2倍,其中50%以上的工业能耗以热能的形式耗散,温度在350℃以下的低品位余热在工业过程中普遍存在。如何实现能源系统向清洁、低碳、高效的方向转型成为中国当前面临的最大问题之一。 近年来,随着集中式供能弊端的逐渐显露,以燃料电池、有机朗肯循环、热电联产为代表的一系列新兴分布式能源技术逐渐成为国内外关注的焦点。其中,固体氧化物燃料电池-燃气轮机(SOFC-GT)混...China is the biggest energy consuming country in the world, accounting for 23% of global energy consumption, but energy utilization efficiency is generally low. According to statistics, energy efficiency is up to 60% in Europe, the average level of other developed countries is 50%, while China is only 33% [1]. On the other hand, China's energy consumption per unit GDP is 3.2 times larger than the ...学位:工学硕士院系专业:能源学院_能效工程学号:3242013115229

    Controlling mechanism of size-specific photosynthetic parameters of phytoplankton in the Taiwan Strait

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    在海洋生态系统中,浮游植物通过光合作用驱动生态系统的物质和能量流动,同时对全球碳循环以及气候的调控具有重要意义。不同粒级浮游植物具有不同的光合作用特征和生态功能,因此,对浮游植物分粒级组成和光合特性的研究有助于深入分析海洋生态系统的结构和功能。本研究以台湾海峡为主要研究海域,分别于2015年11月、2016年3~4月、2016年7月以及2016年8月共4个航次通过对分粒级(>2μm和2μm浮游植物生物量比例呈显著负相关(p2μm浮游植物的更高,这可能是>2μm的浮游植物有更高的PSII效率或者营养盐的存储能力。Ek在所有的航次中均表现为>2μm的浮游植物显著高于In the marine ecosystem, the phytoplankton photosynthesis in the sunlit layer drive the transmission of substance and energy in the ecosystem. The photosynthesis of phytoplankton play a critical role in global carbon cycles and regulating the earth’s climate. Size structure is an important biological feature of the phytoplankton. The study of size structure and photosynthetic physiology of phytopl...学位:理学硕士院系专业:环境与生态学院_环境科学学号:3312014115169

    A study on the properties of sustainable concrete with various industrial by-product

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    北九州市立大学博士(工学)本論文は、フライアッシュ(FA)、高炉スラブ微粉末(GGBS)、木質バイオマスフライアッシュ(BFA)などの産業副産物をセメント代替若しくは細骨材代替として利用したジオポリマー(GP)コンクリートを含むサステナブルコンクリートに焦点を当て、さらに再生骨材を含む多種類の骨材の影響を加味した時の圧縮強度、乾燥収縮、クリープ性状、中性化性状、空隙構造などの複数の特性を包括的に検討したものである。doctoral thesi

    A Business Plan for Dynamic Social Network of Outdoor & Technology Company

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    户外运动产业在中国刚刚步入发展期,市场规模、参与人数占总人口的比例及运动频率,和美国、欧洲相比还有很大的差距。随着我国人民收入水平的日益提高,日常消费中体验型和娱乐类消费比重不断增加,也带来了我国户外用品市场规模每年40%以上的增长,也为户外运动产品的发展带来了契机。本论文运用创业学与管理学的相关理论,通过对中国户外运动行业及竞争态势的研究分析,制定出专业的户外多媒体交流和服务平台的创业计划,既满足了户外运动技术专业性要求,也融入了多媒体社交网络轻松愉快的沟通渠道,这在户外运动行业不仅是一种全新的应用模式,也是一种商业“蓝海”的探索,更将给社交网络、在线旅游服务等细分行业带来诸多发展契机。 ...Outdoor sports industry in China has just entered a period of development, compared to the United States and Europe, there is a great gap in market size, the number of participants in the total population and frequency of exercise. As the income of residents is gradually increasing, the experience-based consumption and entertainment consumption are getting bigger out of the daily consumption, whic...学位:工商管理硕士院系专业:管理学院_工商管理硕士(MBA)学号:1792008115111

    Numerical Study on the Environment of Shenhu and Quanzhou Bays

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    本文以福建中部的两个半封闭的海湾——深沪湾和泉州湾为研究对象,通过数值模拟的方法再现了当地的潮汐潮流,浅滩干湿变化,污染物的输运,百年一遇的台风过境引起的增水现象和台风生成的波浪特征,在此基础上进一步探讨了不同动力机制对当地泥沙动力特性的影响。 结果发现:福建沿岸的潮汐潮流以规则半日潮为主,由于潮差较大,一些浅滩、湿地和暗礁在低潮时会露出水面,在高潮时又重新被海水淹没,形成周期性的干湿变化过程。模拟结果还显示:当天文分潮由外海传入海湾时,动量和连续方程的非线性对流过程和海底的非线性摩擦耗散作用会导致主要分潮的衰减以及浅水分潮的增长,其直接结果就是造成涨落潮流过程的不对称从而成潮汐余流。潮汐余...In this report, two semi-enclosed bays (Shenhu and Quanzhou Bays) which are located at the middle coast of Fujian Province are studied using numerical models. The major focus are put on the local tides and tidal currents, periodical wetting and drying of tidal flats, wave development and water level increase in Shenhu Bay due to the passage of 100-year typhoon. Based on the validated model results...学位:博士后院系专业:海洋与环境学院海洋学系_海洋科学学号:BH1700005

    The Effect of Ex-ante and Ex-post Tail Risk on Stock Market Return

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    本文选用灾难风险担忧指数(RIX)作为考量事前(ex-ante)尾部风险的指标,同时选用根据尾部幂指数分布统计量所提取出的尾部风险值(Tail)作为事后(ex-post)尾部风险的测度。其中,RIX指数是通过SP500的虚值看跌期权的价格计算得出;Tail是利用极值理论,从SP500个股横截面收益数据中提取而来。我们基于SP500指数,及其成分股,对比分析事前(ex-ante)尾部风险与事后(ex-post)尾部风险对SP500股指收益的解释能力和对未来股指收益的预测效果,同时,又以这两种风险指标为依据对SP500个股进行分类并构成不同的资产组合,比照按事前(ex-ante)尾部风险分类的投资...In this paper,we choose the rare disaster concern index as the indicator of the ex-ante tail risk, and choose “Tail”, which relies on the power law distribution as theoretical basis, as the indicator of ex-post tail risk. While RIX is calculated by SP500 index option (out of money put), “Tail” is calculated by the cross section data of individual stock daily return of SP500. We compare the effects...学位:金融硕士院系专业:王亚南经济研究院_金融学学号:2772012115261

    The research of japanese public building entrance space design

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    公共建筑入口空间是联系建筑与城市空间的纽带,是公共建筑与城市空间的中间结合带,是一个包含了多种设计因素和功能要求的有机生态空间,是具有层次性、空间性的思维空间结构,更是建筑设计中的难点,所谓“万事开头难”,建筑入口空间设计已经成为建筑空间设计中的焦点,在建筑空间设计中占据了日渐重要的地位。当今,城市公共建筑入口空间所要表达的内容和思想已日益复杂多元,已经不再是一单纯的建筑出入口空间,它与城市融合衍生为城市空间中又一特殊公共领域。长期以来强调的功能主义设计原则已不能满足建筑入口空间的新形态和新结构,也不能满足人们日渐提升的对城市公共空间的交流、融合的渴望。“机械的,冰冷的城市”是对现代化城市的消...The entrance space of public buildings is the important link of buildings and urban space, it became as the organic ecological space which contains a variety ways of design and functional requirements. The entrance space is also a hierarchy and spatial space cogitation structure. Therefore it is a difficulty in building design. The so-called "All beginnings are difficult ".The design of entrance s...学位:建筑学硕士院系专业:建筑与土木工程学院建筑系_建筑设计及其理论学号:2522008115177

    Model Study of the Influence of Wind and Tide on the Evolution of River Plumes

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    采用三维斜压海流模型模拟了潮汐混合、离岸风以及上升流风对河流羽流发展的影响.尽管潮汐混合和风的搅动作用均能削弱河流冲淡水浮力引起的垂直层化现象,但是其控制机制有所不同:潮汐混合是通过湍流动能自下向上的耗散来完成的,风搅动的方向恰好相反.通过检验河流羽流在潮汐和渤海夏季多年平均风场共同作用下的发展特征,发现计算得到的表层海水盐度分布与实测值相当吻合,因此可以认为河流羽流发展对于渤海夏季盐度分布起着重要作用.A 3-D baroclinic ocean model is used to examine the influence of tide,offshore wind and upwelling-favorable wind on the river plume development.Both tidal mixing and wind stirring can weaken the vertical stratification induced by freshwater buoyancy,but different mechanisms dominate such a process: tidal mixing is accomplished through the upward dissipation of turbulent kinetic energy whereas wind stirring is in the opposite direction.By simulating river plume evolution under the combined action of tide and estival wind field averaged over many years,we have found that the modeled salinity distribution is consistent with the observed one rather well,which means the river plume development plays an important role in adjusting the salinity distribution in the surface layer of Bohai Sea.国家重点基础研究发展计划973计划(2005CB422301)资

    Marketing Strategy Research of Budweiser Beer :The Empirical Study of Xiamen Market

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    中国啤酒行业较欧美国家发展相对较晚,但最近三十年发展迅猛,啤酒产销量已经连续十几年位列世界第一。整个行业在最近几年呈现出产业集中化、利润率低下、消费地域性明显等趋势。伴随着中国经济的快速发展,啤酒消费者对于高档啤酒的需求日益明显,而厂商由于高档啤酒的利润丰厚,对于这块市场的争夺也是愈演愈烈。厦门作为啤酒消费大省福建的重要战略市场,人均年啤酒消费量高,同时作为经济特区,经济发达,消费能力强,对于高档啤酒的接受程度较高,是高档啤酒的良好市场。百威啤酒作为全球知名的啤酒品牌,如何能在厦门这样一个长期被福建本土品牌占领的啤酒市场中更好的进行营销和发展,同时如何作为其他区域市场的借鉴,是本文着重探讨的问...Chinese beer industry develops relatively late comparing to European and American countries, but with the last three decades of rapid development, Chinese beer production and sale volume has been ranked as first over the world for more than last 10 consecutive years. In the recent few years, Chinese beer industry is showing significant trends such as industrial centralization, low profit, regional...学位:工商管理硕士院系专业:管理学院_工商管理硕士(MBA)学号:1792011115081

    An Analysis of the Impacts of Exchange Rate Movements on Employment of Manufacturing Industry in China

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    我国制造业尚处在国际产业链的末端,面对国内不断加重的就业压力,该怎么发展成长壮大,关系到我国未来经济的发展形势,关系到国计民生。选择制造业的就业状况作为本文的研究对象,主要是由于自改革开放以来,中国制造业获得了飞速的发展,目前制造业的出口占中国出口贸易的绝大部分,其开放程度以及吸纳就业的能力也是国民经济其他行业所不能比拟的。然而,自上世纪90年代以来,中国制造业劳动生产率的提高以及规模的扩大,不仅带动了出口的增长和外资的流入,而且还对人民币实际汇率造成了升值的压力。同时,人民币的升值又导致了制造业行业内的巨大就业压力,威胁国内就业形势,从而对中国宏观经济政策的制定提出挑战。因此,有必要深入分析...China’s manufacturing industry has been developing rapidly since the adoption of reformation and opening-up policies. Now, the scale of Chinese manufacturing industry has become the forth in the world. At present, as the pillar industry in our national economy, manufacturing industry draws Chinese economy and the transformation of industrial structure; as the important prop of our economy and soci...学位:经济学硕士院系专业:经济学院经济系_西方经济学学号:2005130070
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