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台湾研究 2024年第1期 1-14页

作者： Institute of Taiwan Studies, chinese academy of Social sciences 中国社会科学院台湾研究所

2024年1月13.,台湾地区领导人和立法机构“二合一”选举落下幕。民进党籍候选人赖清德、萧美琴当选台湾地区正副领导人。台湾地区立法机构总额113.中,中国国民党获52席,民进党获51席,民众党获8席,无党籍及未经政党推荐者获2席.

关键词：中国国民党民进党立法机构台湾地区民众党推荐者二合一候选人

Direct Optimization of Low-thrust Many-revolution Earth-orbit Transfers

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chinese Journal of Aeronautics 2009年第4期22卷 426-433页

作者： Gao Yang academy of opto-Electronics,chinese academy of sciences,{3.,China [a]academy of opto-Electronics Chinese Academy of Sciences Beijing 100190 China

Low-thrust Earth-orbit transfers with 10^- 5-order thrust-to-weight ratios involve a large number of orbital revolutions which poses a real challenge to trajectory optimization. This article develops a direct method to optimize minimum-time low-thrust many-revolution Earth-orbit transfers. A parameterized control law in each orbit, in the form of the true optimal control, is proposed, and the time history of the parameters governing the control law is interpolated through a finite number of nodal values. The orbital averaging method is used to significantly reduce the computational workload and the trajectory optimization is conducted based on the orbital averaging dynamics expressed by nonsingular equinoctial elements. Furthermore, Earth＇s shadowing and perturbation effects are taken into account. The optimal transfer problem is thus converted to the parameter optimization problem that can be solved by nonlinear programming. Taking advantage of the mapping between the parameterized control law and the Lyapunov control law, a technique is proposed to acquire good initial guesses for optimization variables, which results in enlarged convergence domain of the direct optimization method. Numerical examples of optimal Earth-orbit transfers are presented.

关键词： low thrust orbital transfer optimization direct method orbital averaging Lyapunov method

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邓小平新时期军队建设思想的伟大历史贡献

党的文献 2024年第4期 81-86页

作者： academy of Military sciences 中国人民解放军军事科学院

邓小平新时期军队建设思想,是新时期我们党领导筹划国防和军队现代化建设的根本依据和指导方针。邓小平科学判断战争与和平态势,实行国防和军队建设指导思想战略性转变,明确军队在国家大局中的定位与使命,探索和平时期军队建设新特点规... 详细信息

邓小平新时期军队建设思想,是新时期我们党领导筹划国防和军队现代化建设的根本依据和指导方针。邓小平科学判断战争与和平态势,实行国防和军队建设指导思想战略性转变,明确军队在国家大局中的定位与使命,探索和平时期军队建设新特点规律;调整积极防御的军事战略方针,将战略态势上的防御性同军事指导上的积极性统一起来,与时俱进创新军事战略指导;提出建设一支强大的现代化、正规化的革命军队总目标,指明人民军队建设发展的正确方向,为我军全面建设和长远发展提供行动纲领;坚定不移走中国特色精兵之路,科学处理军队建设中数量与质量的辩证关系,创新国防和军队建设发展模式。今天我们回顾和纪念邓小平的伟大军事贡献,关键是学习他在历史大转折时期领导筹划国防和军队现代化建设的新思路新方法,进而深入领会习近平主席在世界百年未有之大变局和中华民族伟大复兴战略全局交织激荡之际与时俱进带领全军进行的伟大理论创造和实践探索,坚定不移在习近平强军思想的科学指导下更加奋发有为地推进强军兴军事业。

关键词：邓小平新时期军队建设思想国防和军队现代化军事战略强军兴军

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science China(Technological sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2,REN WeiJia1,WANG ShiDa1 & WENG LiJun3.1 academy of opto-Electronics,chinese academy of sciences,{3.,China 2 Graduate University of chinese academy of sciences,beijing 100049,China 3.Lanzhou Institute of Chemical Physics,chinese academy of sciences,Lanzhou 73.000,China 1. academy of opto-Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of China,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

中国科学院青岛生物能源与过程研究所2023.度“十大工作进展”

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高科技与产业化 2024年第9期30卷 20-23页

作者： Qingdao Institute of Bioenergy and Process, chinese academy of sciences 中国科学院青岛生物能源与过程研究所

2023.,中国科学院青岛生物能源与过程研究所驰骋奋发、勇毅前行,紧紧围绕“四个率先”和“两加快一努力”的目标要求,进一步强化国家战略科技力量主力军使命担当,共同绘就了研究所繁荣发展的辉煌历程,各项事业取得可喜进展。

关键词：中国科学院生物能源工作进展使命担当研究所主力军辉煌历程青岛

Simulation of aerodynamic performance affected by vortex generators on blunt trailing-edge airfoils

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Science China(Technological sciences) 2010年第1期53卷 1-7页

作者： YANG Ke1,2,ZHANG Lei1,3.& XU JianZhong1,2 1 Institute of Engineering Thermophysics,chinese academy of sciences,beijing 100190,China 2 Key Laboratory of Wind Energy Utilization,chinese academy of sciences,beijing 100190,China 3.Graduate School of chinese academy of sciences,beijing 100190,China 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Wind Energy Utilization Chinese Academy of Sciences Beijing 100190 China3. Graduate School of Chinese Academy of Sciences Beijing 100190 China

An investigation was carried out by numerical simulation on a wind turbine airfoil and a blunt trailing-edge airfoil with and without vortex generators (VGs), and the performance of the airfoils was analyzed. By the simulation of airfoil DU 91-W2-250 it was verified that the numerical method and model were credible. Based on this airfoil, a new one with a blunt trailing edge of 6% chord was blended by symmetrically adding thickness, and its characteristics curves were obtained through computing at key angles of attack. Additionally, the pressure distribution on blended airfoil was analyzed by comparing to the airfoil without blend. The interaction of streamwise vortices induced by VGs with trailing vortex or separation vortex was considered, followed by the uncovery of how VGs can suppress the boundary layer separation.

关键词： vortex generators airfoil blunt trailing-edge

Study on the generator f of the operators I_n and I_t

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Science China Mathematics 2010年第10期53卷 2589-2603页

作者： CHEN HanLin academy of Mathematics and Systems Science,chinese academy of sciences,beijing 100190,China 1. academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

Define two operators In and It,the inner product operator In(g)(x) := j∈Zs(g,f(·-j))f(x-j) and the interpolation operator It(g)(x) := j∈Zs g(j)f(x-j),where f belongs to some space and integer s *** call f the generator of the operators In and *** is well known that there are many results on operators In and *** there remain some important problems to be further *** application we first need to find the available generators (that can recover polynomials as It(p) = p or In(p) = p,p ∈Πm-1) for constructing the relative *** this paper,we focus on the available generator in the class of spline *** shall see that not all spline functions can be used to construct available ***,we do find a spline function in S,of degree m-1,where m is even and S is a class of *** for odd m the problem is still *** on spline functions in this paper are new.

关键词： generator available generator inner product operator spline interpolation operator two-closed refinable

On the contact width in generalized plain strain JKR model for isotropic solids

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Acta Mechanica Sinica 2009年第4期25卷 491-497页

作者： Cong Yan Shaohua Chen LNM, Institute of Mechanics, chinese academy of sciences,100190 beijing. China LNM Institute of Mechanics Chinese Academy of Sciences 100190 Beijing China

Adhesive contact model between an elastic cylinder and an elastic half space is studied in the present paper, in which an external pulling force is acted on the above cylinder with an arbitrary direction and the contact width is assumed to be asymmetric with respect to the structure. Solutions to the asymmetric model are obtained and the effect of the asymmetric contact width on the whole pulling process is mainly discussed. It is found that the smaller the absolute value of Dundurs＇ parameter 13.or the larger the pulling angle O, the more reasonable the symmetric model would be to approximate the asymmetric one.

关键词： Contact mechanics Generalized JKRmodel Asymmetric contact width Oscillatory solution Non-oscillatory solution

The reason of Hopf’s and Oleinik’s proofs for countability of shocks being wrong

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Science China Mathematics 2012年第4期55卷 727-729页

作者： LI BangHe academy of Mathematics and Systems Science,chinese academy of sciences,beijing 100190,China 1. academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

For the number of complete shock curves of a conservation law with one space variable,Hopf in 1950 for the Burger equation,and Oleinik in 1956 for the general,stated that it is at most *** 1979,the present author published an example to show that the statement of Hopf and Oleinik is *** after so long time,the wrong statement for countability still appeared in some publications,which is at least partly due to that some ones felt difficult to understand Hopf and Oleinik’s proofs being ***,pointing out where they went wrong becomes very necessary.

关键词： countability of shocks uncountability of shocks conservation law

Remarks on Hard Lefschetz conjectures on Chow groups Dedicated in celebration of SCIENCE CHINA on the occasion of its 60th birthday

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Science China Mathematics 2010年第1期53卷 105-114页

作者： FU BaoHua Institute of Mathematics, academy of Mathematic and Systems Science, chinese academy of sciences, beijing 100190, China Institute of Mathematics Academy of Mathematic and Systems Science Chinese Academy of Sciences Beijing China

We propose two conjectures of Hard Lefschetz type on Chow groups and prove them for some special cases. For abelian varieties, we show that they are equivalent to the well-known conjectures of Beauville and Murre.

关键词： Chow groups abelian varieties Bloch-Beilinson conjectures Beauville conjecture Murre conjecture