203 research outputs found

    Program Risk Management in Zhuhai Shizimen CBD Construction

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    由于项目群的管理于传统的项目管理有不同之处,论文的研究目标是分析和总结出项目群推进过程中风险管理的分析角度和应对方法,论文的出发点是在传统风险管理理论的基础上,结合项目群风险特别的方法和思路,推进项目群风险管理过程。论文的研究方法是案例研究,对珠海十字门中央商务区会展商务组团一期工程项目群(SZM项目群)为案例进行分析和总结。 研究内容包括三个部分:第一,结合项目群内子项目的逻辑关系,通过对风险的表现形式、量化统一研究风险的本质;研究了风险的在项目群环境下的变化、扩散、转化等;第二,各类项目群内风险的体现和量化、风险损失的判定、项目群环境下的风险行为研究。第三,在这些风险的基础特征研究结果上...On account of the differences between program management and traditional project management, the study objective of the paper is to make an analysis and summary of the perspectives and methods of risk management during program implementation. Based on the theory of traditional risk management, the paper is intended to promote program risk management by integrating special methods and thoughts for ...学位:工程硕士院系专业:管理学院_工程硕士(项目管理)学号:X200915303

    DFT Studies of Anatase TiO2 Nanotubes and Water Adsorption

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    半导体材料的光催化技术在利用太阳能解决能源问题以及环境污染治理等方面具有广泛的应用前景。在众多的半导体光催化材料中,二氧化钛具有无毒性、良好的生物兼容性和化学稳定性,并且在光照下表现出强氧化性、自清洁性等优秀特性,引起人们的特别关注。 20世纪以来,纳米技术得到了很大的发展。与其它纳米材料相比,二氧化钛纳米管具有更大的比表面积,提供了更多的氧吸附位,使其具有更高的吸附性能和反应活性。管壁的弯曲产生曲率效应,从而改变纳米材料的电子结构和力学性能,还能使纳米管的吸附具有选择性。近几十年来,研究者们一直致力于探索二氧化钛纳米管的各种制备方法和改性技术,以期提高二氧化钛的光催化效率和对太阳光的利用率...Photocatalytic technology of semiconductor materials has an extensive application prospect in solving energy issue and environmental pollution treatment with solar energy. Compared with other semiconductor photocatalytic materials, titanium dioxide attracts the focus of attention due to its non-toxicity, good biological compatibility, chemical stability, as well as strong oxidizing and self-cleani...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:2052008115171

    石斑鱼生物学及人工繁育研究进展

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    石斑鱼(Epinephelidae)是名贵的海产鱼类,主要栖息于热带亚热带近岸岩滩和珊瑚礁水域,是岩礁生态系生物群落的重要类群。本文对国内外石斑鱼类生物学、生态学、渔业资源及人工繁育养殖的研究成果进行梳理,综合报道石斑鱼类的形态比较特征,栖息、摄食和繁殖习性,系统演化与分类,种类地理分布,人工繁育等研究进展以及养殖发展概况;报道全球石斑鱼自然资源明显衰退的现状评估以及对石斑鱼资源保护的共识和相关的渔业管理措施。此外,根据作者多年开展的鱼类遗传生物学研究,指出强化我国海域野生石斑鱼资源保护工作,深入开展杂交石斑鱼的基础生物学研究,加强石斑鱼杂交选育行业管理,是我国石斑鱼渔业产业可持续发展的必要保障。科技部科技基础性工作专项(2013FY110700);;海南大学南海海洋资源利用国家重点实验室开放课题(2016001

    An Analysis of the Mechanism of Sales Management of ABB Xiamen Low Voltage Equipment Co., Ltd.

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    成功的销售管理要求适应产品和市场的特性,将良好的管理者个人特质和管理机制有机地结合起来。在销售管理机制中,销售业务管理的要旨在于确保销售工作的恰当目标之确立、销售过程各具体环节的可控性和合目标性;销售人员管理的要旨则在于组织和维护一支斗志高昂、能充分发挥积极性和创造性的销售队伍。良好的销售业务管理和良好的销售人员管理之间是密不可分的,在具体实践中平衡二者的关系乃是一门艺术。本文力图对销售管理机制的各个具体方面做一些适合于厦门ABB低压电器设备有限公司(下简称“ABB公司”)低压开关柜产品领域的探讨。本文共分为四章,简要介绍如下:第一章:ABB公司低压开关柜产品的产品特性和市场特性。这些分析决定...To be successful, the sales management requires the eligibility to the products and the market, the combination of personality of the manager and the management mechanism. In the mechanism of sales management, the keystone of the sales process management is to ensure that a fair target can be established and well-performed, while the sales force management is aimed to organize and maintain a sale ...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:X20021506

    地方政府债务规模的决定因素:探求省际差异的来源

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    从代际公平角度来看,地方政府具有为资本性开支债务融资的理由。但如何衡量地方政府债务融资的合理性与必然性?本文从人口、经济、政治和体制四个方面识别了我国地方政府债务规模的影响因素,并利用审计署公布的全面债务数据,对影响我国地方政府债务规模的因素进行定量分析与检验。计量结果显示:人口年龄结构对债务规模地区差异几无影响;无论是一般预算收入,还是中央补助收入,都正向促进了地方政府债务规模的增加,尤其是中央补助收入刺激了地方政府支出从而增加了地方政府债务融资;政治商业周期对债务规模存在一定影响,在地方政府官员任期的第三年,地方政府债务余额增加最快;财政透明度的省际差异不能解释地方政府债务融资规模的不同。2018年国家社科基金重大项目“中国地区金融风险指数构建与应用研究”(18ZDA093

    气候变化对中国海洋经济可持续发展的影响

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    为评估气候变化及实施减排政策对中国海洋经济的影响,本文构建了中国海洋经济社会经济核算矩阵(marine social accounting matrix,MSAM),并以此为数据基础构建中国海洋经济可计算一般均衡(computable general equilibrium,CGE)模型,并将该模型与气候变化影响模型相结合,从而实现了从气候变化对自然系统的影响到对经济系统影响的转化。论文设计了实施和不实施温室气体减排两种政策时的可能的6种气候变化情景。各情景的模拟分析表明:海平面上升同时考虑天文潮最高潮位、同时考虑最大台风暴潮和最大天文潮耦合影响两种子情景下,中国实施减排政策对沿海GDP的影响要分别比不实施减排政策低0.19%和0.12%;海平面上升叠加天文潮、风暴潮3种子情景下,实施减排政策对海洋经济的影响要分别比不实施减排政策低1.67%、0.72%、0.37%

    Preparation of Crack-free Inverse-opal Films by Template/Matrix Co-assembly

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    近年来,由于在光学、电学和生化等领域具有广泛的潜在应用,有序多孔反蛋白石结构薄膜的研究引起了人们的广泛关注.但是其在制备过程中常常会形成一些无法; 控制的缺陷,限制了这类材料的普及和实际应用.通过使用两种基质前驱体(正硅酸乙酯或丝素蛋白)与胶体小球混合共组装,探究了二元体系共组装法制备无裂痕; 反蛋白石结构薄膜的可行性.并用扫描电镜和可见光谱对薄膜结构进行了表征.结果表明,对于正硅酸乙酯体系,在不影响胶体小球有序排列的条件下,正硅酸乙酯; 在小球间的空隙中发生溶胶凝胶转变,与微球共同组装成有序致密的整体,去除微球模板后,可以得到大规模(>200; mum)无缺陷有序的反蛋白石结构薄膜.而对于大分子丝素蛋白体系,由于它和胶体小球有较强的相互作用力,会抑制胶体小球的有序组装,导致无法形成有序结; 构薄膜.对两种二元共组装体系进行了实验探索,实验结果不仅有助于人们了解共组装方式的适用范围,而且为设计和制备无缺陷反蛋白石薄膜提供了新的途径.Recently, there has been a significant interest in utilizing well-ordered, porous inverse-opal films for applications in optical, electronic and (bio) chemical fields. However, uncontrolled defects are always formed during their preparation process, which limit their practical applications. In this work, we examine the feasibility of using template/matrix co-assembly strategies to fabricate crack-free inverse opal thin films. Polystyrene spheres (PS) are chosen as a colloidal template, and two matrix precursors [tetraethoxysilane (TEOS) precursor and regenerated silk fibroin solution] are used for the current study. Our scanning electron microscope (SEM) and optical spectrum results show that, for the TEOS-based system, the resulting silica gel due to the sol-gel transition of TEOS can effectively fill the gap between particles, but cannot affect the self-assembly of PS colloidal particles. After selective removal of the PS template, centimeter-scale crack-free and well-ordered inverse opal films can be obtained. In addition, for a constant concentration of TEOS, the film thickness and order degree of structure can be simply tuned by adjusting the concentrations of colloidal spheres. In comparison with indirect approach through template self-assembly and liquid infiltration, such a co-assembly approach can effectively minimize the associated cracking and avoid the need for matrix infiltration into the preassembled colloidal spheres. On the other hand, macro-molecule silk fibroin has a relatively strong interaction with PS colloidal particles, which is demonstrated by SEM and confocal images. Due to their interaction, silk fibroin molecules are preferably adsorbed on the surface of PS spheres, which can restrain the self-assembly of colloidal particles. As a result, it cannot form well-ordered silk film based on such co-assembly strategy. That is to say, the co-assembly approach is not suitable for systems that matrices have strong interactions with templates. These findings pave the way to use the template/matrix co-assembly strategy for rationally designing and developing crack-free inverse opal films and to apply such well-ordered and porous materials in a variety of fields.National Natural Science Foundation of China [21401154, U1405226]; 111; Project [B16029]; Natural Science Foundation of Guangdong Province; [2014A030310005]; Fundamental Research Funds for the Central; Universities of China [20720170011

    A Tight-Binding Density Functional Theory Study on Single-Walled Nanotubes from Anatase TiO_ 2 (101) Sheets

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    通过卷曲二维锐钛矿(101)周期性单层片(SHEETS)构造了一系列不同手性((n,0), (0,M), (n,M))的一维单壁TIO2纳米管. 用周期性紧束缚密度泛函理论(dfTb)方法计算并比较了不同管径和手性的TIO2纳米管在几何结构、电子性质等方面的差别. 结果表明: 除了(6,0)管, 其余纳米管随着管径的增大, 应变能和能隙减小. 而在管径相同的情况下, 不同手性的(n,M)纳米管的应变能随着n/M的增加呈现先增大后减小的趋势, 能隙变化不大.A series of chiral anatase(101) nanotubes(NT),which we refer to as(n,0),(0,m),and(n,m),can be formed by rolling up two-dimensional periodic anatase TiO2(101) single layer sheets.Optimized parameters of the atomic and electronic structures of these nanotubes have been calculated using a tight-binding density functional theory method(DFTB).Their band gaps(Eg) and strain energies(Es) have been analyzed as functions of NT diameter.Except for(6,0),the strain energy and the band gap of all the nanotubes of various chirality decrease as the diameter increases.We also find that the strain energy increases first and then decreases rather than varying monotonically with almost constant band gap when n/m ranges from zero to infinitely large.国家自然科学基金(20873107);国家重点基础研究发展规划项目(973)(2011CB808504)资助---

    蚕丝和蜘蛛丝多级结构对力学性能的影响

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    家蚕丝和蜘蛛丝具有力学性能优异、生物可相容和生物可降解等诸多优点。本文阐述了蚕丝和蜘蛛丝的一级结构、二级结构、β-折叠晶体网络(纳米纤维)结构及其形成过程,综述了丝蛋白亲疏水域、分子量和晶体网络结构对力学性能的影响。其中,晶体网络结构的强度是影响力学性能的关键,由拓扑结构、相关长度、取向度和连接(或者相互作用的强度)这4个因素决定。本文为力学性能的控制及提高提供了指导。高等学校学科创新引智计划(B16029);;国家自然科学基金(51773171,U1405226);;福建省科技厅自然科学基金(2017J06019);;中央高校基本科研业务费专项资金(20720160088,20720150218
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