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21.
Research funding has been seen as one of the most important resource in the reward system of science. And usage of publications denotes an interesting perspective of user behavior in scientific communication. This study aims to address the relationship between funding and Usage Count, which is a new metrics item established on the platform of Web of Science. Full records of 300,010 articles published in 2013 were downloaded in October 2015, and divided into six disciplines, including information science library science, education educational research, economics, computer science, materials science, and chemistry. Seven indicators were proposed to measure the impact, including Funding rate, Citation per paper, Usage rate, Usage per paper, Citation difference, Usage difference, and Conversion rate. It concluded funding has impact on usage and citation, and funded papers attract more usage, but varying in different disciplines. Usage Count can be used in the extension of citation metrics but with limits. This study originally engages with usage metrics and detected that there is positive correlation between usage and funding. 相似文献
22.
De-rui Tan 《中国铸造》2018,(5)
正Five Dynasties and Ten Kingdoms Period (963 A.D. and 967 A.D.)The western tower was damaged and is now incomplete. The eastern tower is 7.7 m high.There are two towers, called the eastern tower and the western tower, which were built in 963 A.D. and 967 A.D.,respectively, and are the earliest extant iron towers. There are 1,024 Buddha statues cast on each side of the tower body.The whole tower is made up of 17 castings, which are stacked layer by layer, and each casting is made to be a single 相似文献
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In this paper, we study scheduling games under mixed coordination mechanisms on hierarchical machines. The two scheduling policies involved are ‐ and ‐, where ‐ (resp., ‐) policy sequences jobs in nondecreasing order of their hierarchies, and jobs of the same hierarchy in nonincreasing (resp., nondecreasing) order of their processing times. We first show the existence of a Nash equilibrium. Then we present the price of anarchy and the price of stability for the games with social costs of minimizing the makespan and maximizing the minimum machine load. All the bounds given in this paper are tight. 相似文献
24.
Ye Wan Jun Tan Guangling Song Chuanwei Yan 《Metallurgical and Materials Transactions A》2006,37(7):2313-2316
The focused ion beam technique was employed to investigate the atmospheric corrosion morphology of AZ91D. It was found that
the α matrix of the alloy was preferentially corroded in the areas adjacent to intermetallic phases. The most interesting
finding was that the corrosion products in corrosion cavities were pelletlike, which has never been reported before. 相似文献
25.
P(DBF-VA)型柴油低温流动性改进剂的研制 总被引:1,自引:1,他引:0
针对新疆地产柴油蜡含量较高的特点,以游离基聚合法合成了富马酸双链混合酯和醋酸乙烯酯共聚物型[P(DBF-VA)]柴油低温流动改进剂,利用正交实验研究了单体配比,引发剂用量,溶剂用量,聚合温度对聚合物降冷滤效果的影响。共聚物用IR进行表征,利用XRD初步探讨了该降凝剂的降凝机理。结果表明:该剂能使吐哈—10~#、0~#柴油冷滤点降低10℃和7℃;使独山子0~#柴油冷滤点下降12℃;使石化0~#柴油冷滤点下降8℃;使克拉玛依0~#柴油的冷滤点下降8℃。 相似文献
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基于无源腔的Q值定义,根据能量守恒原理,对连续波腔衰荡技术测量原理进行了推导,并基于多光束干涉理论,就入射光关断时间对腔出射光强信号衰荡线形及测量结果的影响进行了数值模拟和分析,分析表明:入射光的关断时间很大程度上决定着腔出射光功率信号的衰减线形,如果要消除入射光关断时间对测量结果的影响,入射光关断必须小于腔衰荡时间的1%。根据理论分析要求建立了一套测量系统,并对腔损耗约为50ppm的低损无源腔进行了实际测量,实验结果的分析显示,该测量系统测量误差约为0.15ppm。 相似文献
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介绍了平面结构的V波段变频器,该变频器采用平衡变频结构,变频电路主体为平面结构,同时采用了E面探针结构的波导微带转换作为射频信号输出,文中给出了该上变频器的电路软件仿真结果和实测结果以及E面探针波导微带转换的仿真和测试结果,最后给出了该上变频器的实物结构。 相似文献