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11.
对现代篮球进攻战术节奏的探讨 总被引:1,自引:0,他引:1
运用录相观察法、文献资料法等方法对篮球比赛节奏中的进攻战术节奏组成和影响因素进行研究分析,初步勾画了篮球进攻战术节奏的基本框架,并就影响篮球进攻战术节奏的因素进行了探讨。提出了提高篮球进攻战术节奏控制能力的建议,为篮球运动员和教练员的训练和比赛提供参考。 相似文献
12.
This paper discusses some philosophical aspects related to the recent publication of the experimental results of the 2017 black hole experiment, namely the first image of the supermassive black hole at the center of galaxy M87. In this paper I present a philosophical analysis of the 2017 Event Horizon Telescope (EHT) black hole experiment. I first present Hacking's philosophy of experimentation. Hacking gives his taxonomy of elements of laboratory science and distinguishes a list of elements. I show that the EHT experiment conforms to major elements from Hacking's list. I then describe with the help of Galison's Philosophy of the Shadow how the EHT Collaboration created the famous black hole image. Galison outlines three stages for the reconstruction of the black hole image: Socio-Epistemology, Mechanical Objectivity, after which there is an additional Socio-Epistemology stage. I subsequently present my own interpretation of the reconstruction of the black hole image and I discuss model fitting to data. I suggest that the main method used by the EHT Collaboration to assure trust in the results of the EHT experiment is what philosophers call the Argument from Coincidence. I show that using this method for the above purpose is problematic. I present two versions of the Argument from Coincidence: Hacking's Coincidence and Cartwright's Reproducibility by which I analyse the EHT experiment. The same estimation of the mass of the black hole is reproduced in four different procedures. The EHT Collaboration concludes: the value we have converged upon is robust. I analyse the mass measurements of the black hole with the help of Cartwright's notion of robustness. I show that the EHT Collaboration construe Coincidence/Reproducibility as Technological Agnosticism and I contrast this interpretation with van Fraassen's scientific agnosticism. 相似文献
13.
《自然科学进展(英文版)》2022,32(1):10-19
Supercapacitors are widely used for powering flexible/wearable electronics owing to their excellent charge storage capabilities. In this study, MnO2 nanosheets were grown on the surface of graphene using a simple water bath method to prepare graphene/MnO2 composites for fabricating supercapacitors. In addition, two-dimensional black phosphorus was introduced as an additive into the electronic ink based on the as-prepared graphene/MnO2 composites. The characterization and electrochemical analyses results showed that adding black phosphorus considerably improved the capacitive performance of the material, yielding a high specific capacitance of 241.5 ?F ?g-1 at 0.1 ?A ?g-1 and an impressive rate capability improvement from 52.5% to 80.3%. Then the micro-supercapacitor having an area-specific capacitance of 20.15 ?mF ?cm-2 at a scanning rate of 2 ?mV ?s-1 was utilized to demonstrate the practical applicability of this material. To further evaluate the practical applicability of this micro-supercapacitor, the micro-supercapacitor was integrated with a flexible thin-film pressure sensor on paper and cloth through screen printing. 相似文献
14.
提出了汉化井眼轨迹控制专家系统的基本思路与结构的基本框架,其特点是利用计算机汉字图形用户界面技术,把井眼轨道设计、下部钻具组合(BHA)特性分析、BHA数据库管理、BHA结构优选设计、钻井过程的计算机模拟及钻井数据处理等融为一体。菜单选择、对话框式数据输入,操作方便。提出了BHA数据库的概念。它是井眼轨迹控制技术软件向智能化发展的基础。 相似文献
15.
16.
对小氮肥企业中闲置机械设备的有关问题进行了分析,提出了再利用的措施,也对闲置设备再利用过程中出现的问题作了初步的探讨。 相似文献
17.
徐水源 《四川师范大学学报(自然科学版)》1996,19(5):43-45
本文系统地阐明了晶体中电子运动的性质,导体及半导体和绝缘体的区别,在此基础上,澄清了一些教材中不明确的空穴概念。 相似文献
18.
Luca Lusanna Massimo Pauri 《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2006,37(4):692-725
“The last remnant of physical objectivity of space–time” is disclosed in the case of a continuous family of spatially non-compact models of general relativity (GR). The physical individuation of point-events is furnished by the autonomous degrees of freedom of the gravitational field (viz., the Dirac observables) which represent—as it were—the ontic part of the metric field. The physical role of the epistemic part (viz. the gauge variables) is likewise clarified as embodying the unavoidable non-inertial aspects of GR. At the end the philosophical import of the Hole Argument is substantially weakened and in fact the Argument itself dissolved, while a specific four-dimensional holistic and structuralist view of space–time (called point-structuralism) emerges, including elements common to the tradition of both substantivalism and relationism. The observables of our models undergo real temporal change: this gives new evidence to the fact that statements like the frozen-time character of evolution, as other ontological claims about GR, are model dependent. 相似文献
19.
本文分析丁吐哈盆地西山窑、八进湾煤层井下复杂情况及其原因.着重探讨了煤层井壁不稳定机理,结果表明,煤层井壁不稳定是物理、化学、力学与机械等因素的综合效应。 相似文献
20.
研究了一种(2+1)维准静态旋转质量黑洞的热辐射。在准静态过程中,此黑洞的 界面分裂为两个。因此,采用不同的乌龟坐标变换和解析延拓方法,可得到这种时空的霍金辐射温度。 相似文献