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连梁拉索的防落梁效果研究
Research of Cable-Unseating Prevention Device
 [PDF]

, 罗韧
Open Journal of Transportation Technologies (OJTT) , 2013, DOI: 10.12677/OJTT.2013.23039
Abstract:
桥梁上部结构发生落梁是导致桥梁结构发生倒塌的重要原因之一。防落梁措施的主要功能就是防止上部结构在地震过程中发生落梁。本文选取某连续桥梁作为分析对象,通过增加梁体搁置长度和设置连梁拉索装置的方法,结合大型有限元软件ABAQUS进行模拟分析,研究防落梁措施的效果。从分析结果可知,仅增加梁体搁置长度或局部设置连梁拉索并不一定能防止落梁,需要从桥梁结构整体防落角度来设置防落梁措施。
The upper structure falling is one of the important reasons that cause the bridge collapsed. Beam lowering prevention measure’s main function is to prevent the upper structure falling in a earthquake. This article takes a multi-scale bridge as the analysis object, using the large finite element software ABAQUS simulation to analyze it. This paper studies the effects of beam lowering prevention measure, by the way of increasing the suspended length of the girder and setting the cable-unseating prevention device. Through the analysis results, we can find out that only increase the suspended length of the girder and set the cable-unseating prevention device locality is not necessarily useful. The bridge structure should be viewed as a whole to set the beam lowering prevention measures.
喷射沉积多孔材料楔形压制工艺的研究现状与发展趋势
Status and Development Trend of Wedge Pressing Technology for Spray-Deposited Porous Materials
 [PDF]

张贤,
Material Sciences (MS) , 2015, DOI: 10.12677/MS.2015.55027
Abstract:
楔形压制技术是一种基于多道次局部小变形累积致整体成形实现大尺寸喷射沉积多孔材料的致密化的先进工艺。本文综述了喷射沉积多孔材料的致密方法,对比了楔形压制与其他传统致密方法,说明了采用楔形压制工艺的优势和必要性;分别介绍了喷射沉积方形件、环形件与管形件楔形压制的原理、技术特点及研究应用;分析了楔形压制工艺存在的一些局限性;展望了楔形压制技术的发展趋势,认为梯温楔形压制的温度梯度控制精度有待提高;环形件楔形压制的致密均匀性和压制工艺有待进一步深入研究;管形件楔形压制则在压制效率和压制后管坯的尺寸精度有待提高;楔形压制工艺应拓展到其他形状坯料的致密或预成形,也不应局限于坯料的致密,可发展为成形工艺,拓展楔形压制的应用范围。
Wedge pressing is an advanced densification technology for compressing spray-deposited porous preforms of large scale by accumulating deformation as to integral forming. Densification method of spray deposited porous materials is introduced. Wedge pressing is compared with traditional compressing methods to reflect superiority and necessity of wedge pressing adopting. Principle, technical characteristics and research utilizes of wedge pressing are introduced separately, and limitations and development trends of this technology are analyzed. It is considered that control accuracy of temperature gradient of temperature gradient wedge pressing should be improved; compact homogeneity and compact process of ring billet should be investigated further; and compact efficiency and dimensional accuracy of tubular billet as pressed should be improved. Wedge pressing will be applied to compaction or preforming of billet of other shapes except bulk, ring and tube. Furthermore, wedge pressing should not be restricted to densification; it can be developed into a forming technology to expand its application range.
小水电项目建设碳减排融资的案例分析
A Sample of the Carbon Finance in Mini-Hydropower Station
 [PDF]

, 王振全
Journal of Low Carbon Economy (JLCE) , 2013, DOI: 10.12677/JLCE.2013.21005
Abstract:
本文通过案例的项目投资现金流的比较分析表明,碳减排融资是解决小型水电站投资收益率低的有效途径之一,解释了其对于融资方面的可行性,进而为我国发展小型水电站提供了可靠的理论依据。本文还估算了碳减排投资方的预期收益,结果表明其收益率远大于水电站本身的收益率。为此本文认为,我国应鼓励国内资本在碳减排方面的投资以及碳交易市场的尽快完善。
This paper shows that carbon reduction financing is one of the effective ways to solve the problem of mini-hydropower investment low income by the case of project cash flow analysis, explains its feasibility for financing, and thus provides a reliable theoretical basis for the development of mini-hydropower stations in China. This paper also estimates the expected return of investors in carbon emission reduction and the results shows that the yield including the carbon financing is much larger than itself. So it is believed thatChinashould encourage domestic capital investment in carbon reduction and perfect carbon trading market as soon as possible.
基于电流幅值量测的微电网状态估计
State Estimation of Micro-Grid Based on Current Amplitude Measurement
 [PDF]

, 赵向阳, 罗文
Smart Grid (SG) , 2015, DOI: 10.12677/SG.2015.53015
Abstract:
在微电网能量管理中,实时数据库中数据的可靠性和准确性是进行控制、操作及准确分析的基础。数据采集系统中采集的实时数据不齐全以及量测数据不精确是潮流计算等高级分析功能难以解决的,因此对微电网实时数据进行状态估计势在必行。本文在分析了状态估计基本原理的基础上,采用以支路电流的实部和虚部为状态变量的状态估计方法,对微电网中7条支路进行状态估计,其理论估计的支路电流幅值和实际值偏差处于可接受范围之内。
The reliability and accuracy of real-time data in the database is the foundation of control, operation and accurate analysis in the micro-grid energy management. The data collection of the real- time data acquisition system is not complete and there are inaccurate measurements; it’s difficult for the power flow calculation and other advanced analysis functions to resolve those problems. So the micro-grid state estimation for the real-time data is imperative. In this paper, seven bran- ches in the micro-grid are analyzed in state estimation after the analysis of the basic principles of state estimation using the real and imaginary parts of the current in branches as the state variables. The deviation of theoretical estimate of the branch current amplitude and the actual value is within the acceptable range.
影响吉林省高考考生志愿填报的地域因素分析—以上海高校为例
Analysis on the Regional Factors That Affect the Applicants of Jilin Province’s College Entrance Examination to Fill in the Application Form —Taking Universities in Shanghai City as Examples
 [PDF]

, 姚洁
Advances in Education (AE) , 2016, DOI: 10.12677/AE.2016.66039
Abstract:
近年来,吉林省高考考生在填报志愿时,除了考虑该学校的整体水平,即该校是否属于985工程或211工程以外,更多的是考虑到地域因素,像北京、上海等大城市的高等院校更成为了报考的热点。为此,本文在对近年来吉林省高考报考总体情况进行分析的基础上,深入分析了上海在吉林省理科第一批次录取的高等院校简况及其近年来录取分数变动趋势,以期为吉林省高考考生的志愿填报提供一定依据。
In recent years, while filling in the application form, the applicants of college entrance examina-tion in Jilin province consider much more about the regional factors in addition to the overall status of the school, namely whether the school belongs to the “985” or “211” engineering projects or not. For example, colleges and universities in Beijing, Shanghai and other big cities have been warmly welcomed. Therefore, based on analyzing the overall application status of Jilin Province’s college entrance examination in recent years, this paper made in-depth analysis on the status of universities in Shanghai city which belong to the first batch of admission in science in Jilin Province and also on changing tendency of their admission scores in recent years, in order to provide a basis for the applicants of Jilin province’s college entrance examination.
美英高校绩效评价指标体系的比较分析及启示
 [PDF]

李祖超,
Evaluation and Management (EM) , 2016, DOI: 10.12677/em.2016.94009
Abstract:
本文从绩效评价指标体系对美英两国高等教育推动作用入手,对两国的高校绩效指标体系的不同之处做了分析,并针对两国高校绩效指标的可取之处进行评价,据此得出如何构建我国高校绩效评价指标体系的启示。
This article from the aspect of the performance evaluation index system of higher education to promote the role of the United States and Britain, analyzes the difference between the two coun-tries’ performance index system, and evaluates the merit of the performance indicators of the two countries. Based on this, the paper draws a conclusion on how to construct the index system of performance evaluation in China’s colleges and universities.
The Design of Television station advertisement Management System base three layers C/S mode
基于三层C/S模式的电视台广告管理系统设计


计算机系统应用 , 2007,
Abstract: 在分析比较了C/S和B/S构架的特点的基础上,针对电视台广告业务的实际需求,提出了一种基于三层C/S数据库模式的广告管理系统的解决方法,并对该系统核心功能模块的设计作了详细的阐述,最后总结了该系统的技术特点.
浅析吴有训的物理教育思想

现代物理知识 , 2002,
Abstract: 吴有训 (1891— 1977) ,1916年考入南京高等师范学校 ,192 0年毕业。 192 1年考入美国芝加哥大学 ,师从著名物理学家康普顿进行X射线散射光谱研究 ,他以精湛的实验技术和卓越的理论分析验证了康普顿效应 (后有人称为康普顿 -吴有训效应 ) ,被誉为“世界重大科学发现上的第一位名垂史册的中国人”。回国后 ,他先后任中央大学物理系系主任(192 7)、清华大学物理系教授、系主任、理学院院长(192 8— 1937)和西南联大理学院院长 (1937— 194 5 )及中央大学校长 (194 5— 194 8)等职。解放后任中科院副院长直至逝世。吴有训参加教学工作主要是在…
推进落实“公开、公平、公正”原则促进源头创新与人才培养——浙江省自然科学基金委员会办公室工作思路回顾与反思

自然科学进展 , 2007,
Abstract:
NOAA16卫星积雪识别和参数提取

冰川冻土 , 2004,
Abstract: 通过对积雪、地物和云进行光谱分析,指出传统的NOAA-AVHRR可见光和近红外波段进行云雪识别存在困难,而雪在红外波段的低反射性特点是区分云雪的一个可行途径.利用NOAA16气象卫星新增的1.6μm红外波段,对中国北方冬季的卫星积雪图象进行识别,结果显示,云雪可以准确区分.同时,提出了利用AVHRR资料估算积雪面积、积雪深度和积雪时间的方法,并对积雪深度进行了精度检验.
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