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主动对日双轴跟踪物理理论
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作者 李杰吾 《太阳能学报》 EI CAS CSCD 北大核心 2018年第11期3022-3025,共4页
应用物理学的研究方法,以地球自转轴为研究对象,通过分析日地运行的基本特点,推导出世界各地共同主动对日双轴跟踪的数学规律。在同步卫星精确时间的控制下,尽量避免地面气候的干扰,使这种双轴跟踪技术可做到数十年内主动而精确正对太阳... 应用物理学的研究方法,以地球自转轴为研究对象,通过分析日地运行的基本特点,推导出世界各地共同主动对日双轴跟踪的数学规律。在同步卫星精确时间的控制下,尽量避免地面气候的干扰,使这种双轴跟踪技术可做到数十年内主动而精确正对太阳,且成本低,可为光伏增效降本提供核心技术。 展开更多
关键词 太阳能 主动对跟踪 日轴
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太阳观测卫星的数传天线波束及其指向设计
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作者 曾麒麟 于锡峥 熊蔚明 《国防科技大学学报》 EI CAS CSCD 北大核心 2019年第6期135-142,共8页
针对三轴稳定对日指向姿态的太阳同步轨道卫星,提出为获得最大对地数据传输时间的天线波束设计及布局方案。根据某型太阳观测卫星的轨道姿态设计方案,建立数传天线对指定地面站的天线波束指向仿真模型;使用卫星工具包STK仿真软件,分析... 针对三轴稳定对日指向姿态的太阳同步轨道卫星,提出为获得最大对地数据传输时间的天线波束设计及布局方案。根据某型太阳观测卫星的轨道姿态设计方案,建立数传天线对指定地面站的天线波束指向仿真模型;使用卫星工具包STK仿真软件,分析不同波束角方案及其可能的指向对数传时间的影响,发现了对日指向卫星与对地指向卫星在数传时间上的不同规律,找到最优的天线波束布局来获得最大的数传时间;根据星载数传能力与不同天线波束宽度之间的关系,获得传输数据的最佳天线波束宽度,为这类卫星数传天线的波束设计及其布局提供设计依据。 展开更多
关键词 太阳观测卫星 稳定对指向姿态 太阳同步轨道 定向波束天线 卫星天线布局 STK仿真软件
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Identity Transformation of China through the Anti-Monopoly Law Penalty on Japanese Automotive Parts and Bearings Enterprises
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作者 Ji Huanhuan 《International English Education Research》 2014年第11期1-6,共6页
The identity transformation of China is analyzed through the legal punishment given by China's National Development and Reform Commission on Japanese automotive parts and bearings enterprises that broke China's Mono... The identity transformation of China is analyzed through the legal punishment given by China's National Development and Reform Commission on Japanese automotive parts and bearings enterprises that broke China's Monopoly Law by price- fixing in the automotive parts market of China for more than ten years. The standards for illegal conduction this penalty based are the international Cartel rules, the specific legal procedure is beyond the main concern of this study so the obscurity of how this penalty decided is kept aside for the sake of respecting the painstaking labor fruits of relevant executive departments as well as for dispensing political sensitivity related to any academic analysis developed. Three Japanese newspaper reports concerning this penalty fine are selected for critical discourse analysis. Emotional ambience of them is derogative, neutral, and approving respectively. Foucault's triad relationship of discourse-power-identity is borrowed and the postmodernists' view of the "other" is corroborated with the self-presentation of China. Positive self-presentation is underscored by the contrast of negative other-presentation and vice versa, the negative commendation on this punishment event revealed in certain news coverage is to lessen the negative image of Japanese enterprises because of their shared Japanese identity. However their fundamental tone maybe, the fact that China evolves to be able to handle the illegal international events in its confines with dignity is tacitly recognized as a warning in three newspapers. The new identity of China is thus highlighted as the role of the other by the Japanese media. The reason why Japanese accept it instead of staging substantial resistance is analyzed from the Japanese cultural considerations of the hierarchical sequence or the "weizhiyishi" (positional consciousness or postural consciousness), and the practical reasons of why Hitachi and Nachi commit self-confession is analyzed. All these responses from Japanese side are the manifestation of China's being in charge of the situation, it has the ball at its feet in this power gaming. 展开更多
关键词 Identity transformation power gaming discursive analysis penalty fine
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Discontinuities effect on drilling condition and performance of selected rocks in Nigeria 被引量:1
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作者 Adebayo Babatunde Bello Wasiu Ademola 《International Journal of Mining Science and Technology》 SCIE EI 2014年第5期603-608,共6页
The study examined joint discontinuity spacing effect on drilling condition and performance in selected rocks in llorin and Ibese areas, Nigeria. Five samples for each rock type (gneiss and limestone) were tested in... The study examined joint discontinuity spacing effect on drilling condition and performance in selected rocks in llorin and Ibese areas, Nigeria. Five samples for each rock type (gneiss and limestone) were tested in the laboratory for chemical, physical and mechanical properties. Dip direction and joint spacing were measured using compass clinometers. The chemical composition was determined using X-ray Fluores- cence (XRF) spectrometer. The results show that gneiss has SiO2 of 61.88g and limestone has CaO content of 52.3g. The average dry density of gneiss and limestone are 2.6 and 2.39 g/cm^3, respectively. The uniaxial compressive strength of gneiss and limestone are 195 and 93.83 MPa, respectively. These rocks are classified as strong and moderately strong rock. Gneiss and limestone have mean joint discontinuity spacing of 0.79 and 0.25 m, which classified them as moderate and wide joint spacing respectively. Joint spacing was correlated with specific energy, bit wear and uniaxial compressive using Statistical Package for Social Science (SPSS). The regression model has multiple coefficient of correlation of R^2 = 0.791 and R^2 =0.995 for gneiss and limestone, respectively. The variation in joint spacing could be attributed to spe- cific energy, bit wear and uniaxial compressive strength which affect drilling condition and performance. Ultimately, as joint spacing gets closer, the drilling velocity increases, drill string will be stable. 展开更多
关键词 Joint spacing GneissLimestone Regression Composition
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Influences of different forces on the bubble entrainment into a stationary Gaussian vortex 被引量:16
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作者 ZHANG AMan NI BaoYu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第11期2162-2169,共8页
Simulations of bubble entrainment into a stationary Gaussian vortex are performed by using the combined particle tracking method(PTM)and boundary element method(BEM).Before the bubble is captured by the vortex core,os... Simulations of bubble entrainment into a stationary Gaussian vortex are performed by using the combined particle tracking method(PTM)and boundary element method(BEM).Before the bubble is captured by the vortex core,oscillation and migration of the quasi-spherical nucleus are solved by using improved RP equation and the momentum theorem in the Lagrangian reference frame simultaneously,and the trajectory of the nucleus presents a kind of reduced helix shape.After captured by the vortex core,the bubble grows immediately and moves and deforms along the vortex core axis.The non-spherical evolution and deformation of the bubble is simulated by adopting a mixed Eulerian-Lagrangian method.The output of quasi-spherical stage is taken as the input of non-spherical stage,and all the behaviors of the entrained bubble can be simulated such as inception,motion,deformation and split.Numerical results agree well with published experimental data.On this basis,the influences of various factors such as viscosity,surface tension,buoyancy are studied systemically.Hopefully the results from this paper would provide some insight into the control on vortex bubble entrainment. 展开更多
关键词 BUBBLE ENTRAINMENT gaussian vortex trajectory split
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