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111.
采用计算流体动力学的方法,利用STAR-CCM+软件对某一车型挡风玻璃除霜性能进行数值模拟分析。通过对出风口格栅进行调整,改变了暖风气流与挡风玻璃之间碰撞角的大小与碰撞点的位置,优化了挡风玻璃表面暖风气流的分布,提升了除霜性能,为汽车除霜风道的设计和改善车辆除霜性能提供了参考。  相似文献   
112.
The role of the library is to assist citizens in skills development critical to national interest and empowerment as literacy ambassadors, in general. Specifically, the work by the Federal Geographic Data Committee (1994) indicates that spatial literacy is for every citizen and not just a set of workforce specialists. Hence, the use of maps in decision making and problem solving will become fundamental to all professions, including library professionals. Thus, a spatial literacy awareness and rationale for such as standard job ability is discussed as a future librarian workforce proficiency and knowledge transfer medium.  相似文献   
113.
[目的/意义]本文通过对2019年国际数字图书馆联合会议(Joint Conference on Digital Library,JCDL)的录用论文进行整体回顾,梳理了本届年会的最新研究成果与学科发展动态,以助国内图情领域学者更好地了解本届年会成果,把握国际数字图书馆领域研究的前沿热点问题。[研究设计/方法]采用文献综述的方法进行研究。[结论/发现]本届年会更加关注数字图书馆如何通过多源数据的融合、数字人文馆藏资源的利用等实现信息服务深度融合;数字图书馆如何通过海量大数据挖掘与利用、用户行为分析提升其服务水平;如何通过对学术文本资源深入挖掘,实现信息计量学在学术评审、学术评价等方面的创新应用。[创新/价值]本文揭示了国际数字图书馆领域的最新发展态势,展望了未来数字图书馆领域的学术前沿方向。  相似文献   
114.
In fall 2016, the Columbia-Cornell collaboration in the area of Slavic & East European resource coordination and sharing celebrated its sixth year. The author reviews particulars of the development, implementation, and function of this program as well as some of the challenges that face such cross-institutional efforts.  相似文献   
115.
Educational institutions, like most social service organizations, need to recognize intersectionality and complexity and move away from monolithic conceptions of homelessness – if they recognize homelessness at all. This first person account of a gay, Cambodian refugee illustrates the enormous complexity schools face in forming institutional responses for the needs of homeless, highly mobile, and economically displaced children and youth. This article demonstrates an effort to avoid reductionist definitions of homelessness and to include experiential representations of humans living at the margins (under the 5th Avenues of the world, in central parks, in downtown shelters, outside of the ethical and systemic “home” of current ideologies and social orders, under the politics of HIV in Africa, as refugees and as those “othered” by dominant social narratives). The research takes place in the context of the At Home At School program at Washington State University.  相似文献   
116.
Based on a nation-wide survey of higher education graduates, this paper analyzes the impact of family background, using paternal occupation and education as indicators, on their scores in the National College Entrance Examination, the level and type of higher education institutions they attend, their employment after graduation, and the income they receive from their first job. It has been found that there are wide disparities among students with different family backgrounds in both access to higher education and their potential employment in China nowadays. This paper also studies how those influences happen. __________ Translated from Peking University Education Review, 2005 July (3)  相似文献   
117.
We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterized by an assemblage of garnet, orthopyroxene, spinel, cordierite, biotite, plagioclase and quartz. Symplectites of orthopyroxene and spinel, and orthopyroxene and cordierite indicate decompression under UHT conditions. Mineral chemistry shows that the or-thopyroxenes have high XMg and A12O3 contents (up to 9.23 wt%). Biotites are enriched in TiO2 and XMg and are stable under granulite facies conditions. The garnet and quartz from the rock carry monophase fluid inclusions which show peak melting temperatures of around -56.7℃, indicating a pure CO2 species being presented during the ultrahigh-T metamorphism in the Altay orogenic belt. The inclusions homogenize into a liquid phase at temperatures around 15.3-23.8℃ translating into CO2 densities of the order of 0.86-0.88 g/cm3. Based on prelim  相似文献   
118.
Classificationofaircleanlinessinanykindofclean roomsandcleanzoneswillbeaccomplishedintermsofconcentrationofairborneparticles .Alightdiscreteair borneparticlecounter (hereafterreferringtoasAPC)isusedtodeterminetheconcentrationofairborneparticlesequaltoandlargerthanthespecifiedsizesatdesignatedsamplinglocation[1,2 ] .Inthepracticalmeasurementofparticleconcentrationincleanrooms,itisfoundthetest ingresultsofparticlenumberinthesameareacountedbydifferentparticlecountersarequitedifferentanduptoanord…  相似文献   
119.
Polarography     
J Heyrovsky’s invention of polarography in which a dropping mercury electrode is used in the electrochemical cell revolutionised electroanalysis, study of electrode kinetics and adsorption studies on mercury electrodes. Polarography has also directly contributed to the development of new and innovative ideas in electrochemical techniques, instrumentation and applications  相似文献   
120.
中学生物理实验操作能力是物理实验能力的核心部分。本文探讨了物理实验操作能力的定义及其特点 ,并在此基础上构建了物理实验操作能力的结构模型 ,讨论了该模型的特点 ,即整体性、静态性、动态性和自调性。根据物理实验操作能力的结构模型及其特点 ,给出了物理实验操作能力的主要指标  相似文献   
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