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The low-mass X-ray binary-millisecond radio pulsar birthrate problem revisited

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science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 125-129页

作者： DAI HaiLang1,2.& LI XiangDong2.1 Faculty of science,Jiangsu university,Zhenjiang 2.2.13,{2. 2.department of Astronomy,nanjing university,nanjing 21.093,{2. 1. Faculty of science Jiangsu University Zhenjiang 212013 China 2. department of Astronomy Nanjing University Nanjing 210093 China

We investigate the birthrate problem for low-mass X-ray binaries(LMXBs) and millisecond radio pulsars(MRPs) in this *** consider intermediate-mass and low-mass X-ray binaries(I/LMXBs) to be the progenitors of MRPs,and calculate their evolutionary response to the cosmic star formation rate(SFR) both semi-analytically and *** a typical value(1 Gyr) of the LMXB lifetime,one may expect comparable birthrates of LMXBs and MRPs,but the calculated number of LMXBs is an order of magnitude higher than that observed in the ***,we suggest that the birthrate problem could be solved if most MRPs have evolved from faint to rather than bright *** former may have a population of-104 in the Galaxy.

关键词： close binaries general pulsars star formation X-ray stars

Uniquely ergodic property of minimal probability measure in positive definite Lagrangian systems

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science china Mathematics 2006年第12期49卷 1864-1866页

作者： CHEN Jing & BAI Yuzhen department of Mathematics, nanjing university,{2., china department of Mathematics, Qufu Normal university, Qufu 2.3165, china 1. department of Mathematics Nanjing University Nanjing 210093 China 2. department of Mathematics Qufu Normal University Qufu 273165 China

Mane conjectured that every minimal measure in the generic Lagrangian systems is uniquely ergodic. In this paper, we will show that the answer to the Mane's conjecture is negative by analyzing the structure of the sup... 详细信息

关键词： minimal probability measure,uniquely ergodic,Mather theory,Lagrangian systems.

A new smoothing scheme for mathematical programs with complementarity constraints

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science china Mathematics 2010年第7期53卷 1881-1890页

作者： YAN Taodepartment of Information and Computational sciences, College of science, nanjing university of science and Technology, nanjing 2.0094, china 1. department of Information and Computational sciences College of Science Nanjing University of Science and Technology Nanjing 210094 China

In this paper, we consider a mathematical program with complementarity constraints (MPCC). We present a new smoothing scheme for this problem, which makes the primal structure of the complementarity part unchanged mostly. For the new smoothing problem, we show that the linear independence constraint qualification (LICQ) holds under some conditions. We also analyze the convergence behavior of the smoothing problem, and get some sufficient conditions such that an accumulation point of stationary points of the smoothing problems is C (M, B)-stationarity respectively. Based on the smoothing problem, we establish an algorithm to solve the primal MPCC problem. Some numerical experiments are given in the paper.

关键词： mathematical program with complementarity constrains MPEC-LICQ B-stationarity C-stationarity M-stationarity

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science china {2. sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2. JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of earth Environment, Chinese Academy of sciences, Xi’an 710075,{2. 2.Graduate university of the Chinese Academy of sciences, Beijing 100049,{2. 3 College of Resources and Environmental science, nanjing Agricultural university, nanjing 2.0095,{2. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China Graduate university of the Chinese Academy of sciences Beijing 100049 China College of Resources and Env

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2. the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Electron surfing acceleration in a current sheet of flares

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science china(Physics,Mechanics & Astronomy) 2009年第11期52卷 1810-1812页

作者： WANG DeYu1 & LU QuanMing2.1 Purple Mountain Observatory, nanjing 2.0008, china 2.School of {2. and Space sciences, university of science and Technology of china, Hefei 2.002., china Purple Mountain Observatory Nanjing 210008 China School of earth and Space sciences University of Science and Technology of China Hefei 230026 China

A model of electron acceleration in a current sheet of flares is studied by the analytical approximation solution and the test particle simulation. The electron can be trapped in a potential of propagating electrostatic wave. The trapped electron moving with the phase velocity v p of wave may be effectively accelerated by ev p/c × B z force along the outflow direction in the current sheet, if a criterion condition K > 0 for electron surfing acceleration is satisfied. The electron will be accelerated continuously until the electron de-trap from the wave potential at the turning point S.

关键词： electron acceleration electrostatic wave current sheet

TRANSMISSION MOMENTARY EFFICIENCY BASED ON THE D'ALEMBERT-LAGRANGE EQUATION FOR INVOLUTES GEARS

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 272-275页

作者： Liang Yi Lai Changying School of Mechanical Engineering,nanjing university of {2. and Technology,nanjing 2.0094, china School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China department of science and Technology Studies University College London WC1E 6BT UK

The D'Alembert-Lagrange equation is introduced and used to derive theformulas of momentary efficiency for external gearing of standard involutes spur gears. The gearingswith correct and increased center distance are discussed. The momentary efficiency formula iscalculated and analyzed using software Matlab. The derived formula of momentary efficiency is alsocompared with the traditional formula.

关键词： D'Alembert-Lagrange equation Involutes gear Momentary efficiency

Low-complexity distributed differential spacetime coding scheme for amplify-and-forward cooperative networks

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science in china(Series F) 2009年第8期52卷 1418-1427页

作者： YU XiangBin1,2. BI GuangGuo3 & XU WeiYe4 1 College of Information science and Technology, nanjing university of Aeronautics and Astronautics, {2. 2.0016, china 2.department of Electronic Engineering, City university of Hong Kong, Hong Kong, china 3 National Mobile Communications Research Laboratory, Southeast university, {2. 2.0096, china 4 department of Communication Engineering, {2. Institute of Technology, {2. 2.1167, china College of Information science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China department of Electronic Engineering City University of Hong Kong Hong Kong China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China department of Communication Engineering Nanjing Institute of Technology Nanjing 211167 China

By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward （AF） method for wireless cooperative networks. The scheme requires no knowledge of the channel state information at both transmitters and receivers, and effectively decreases the realization complexity due to no channel estimation. Moreover, it has lower decoding complexity and higher coding advantage than the existing scheme, thus avoiding the shortcoming of exponential decoding complexity of some existing schemes. According to the pairwise error probability （PEP） analysis of the system, the power allocations of source and relay terminals are jointly optimized, and as a result, the PEP is minimized, which will provide a helpful guideline for system design. Numerical calculation and simulation results show that the developed scheme is superior to the existing scheme. Moreover, the scheme with optimal power allocation yields obvious performance improvement over that with equal power allocation.

关键词： differential space-time coding cooperative communication amplify-and-forward method power allocation

Non-p-generic and Strongly Nonbranching Degree

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Acta Mathematica Sinica,English Series 1994年第1期10卷 30-41页

作者： Ding Decheng department of Mathematics nanjing university {2.,2.0008 china 1. department of Mathematics Nanjing University 210008 Nanjing China

It has been proved by the author that every p-generic degree is *** this paper we construct an *** which is strongly nonbranching and *** means that the class of nonbranching degrees does not coincide with the class o... 详细信息

关键词： Non-p-generic and Strongly Nonbranching Degree NB

Surface configurations during annealing of sputter-deposited NiTi thin films

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Chinese science Bulletin 1997年第23期42卷 2019-2020页

作者： GONG Fengfei, JIANG Enyong, SHEN Huimin and WANG Yening1. department of Applied Physics, Tianjin university, Tianjin 300072.The National Laboratory of Solid State Microstructures,{2., nanjing 2.0008 Center for Advanced Studies in science and Technology of Microstructures, nanjing 21.093, china 2. department of Physics, Tianjin university, Tianjin 300072. china 3. National Laboratory of Solid State Microstructures,{2., nanjing 2.0008, Center for Advanced Studies in science and Technology of Microstructures, nanjing 21.093, china. department of Applied Physics Tianjin University Tianjin The National Laboratory of Solid State Microstructures Nanjing University Nanjing Center for Advanced Studies in science and Technology of Microstructures Nanjing China department of Physics Tianjin University Tianjin China National Laboratory of Solid State Microstructures Nanjing University Nanjing

SPUTTER-DEPOSITED NiTi thin films are becoming more and more important because of their po-tential applications to the intelligent thin-film systems. The as-deposited NiTi thin films pre-pared by magnetron sputtering are generally amorphous. Because the amorphous NiTi thinfilms cannot show shape memory effect, they should be crystallized under appropriate anneal-

关键词： NiTi Surface configurations during annealing of sputter-deposited NiTi thin films