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约化为三对角矩阵的改进Newton算法

高等学校计算数学学报 1982年第3期 202-207页

作者：吴育华天津大学

一、引言本文用g(x)表示目标函数的梯度,G(x)表示目标函数f(x)在x点的Hessain矩阵,p(x)表示在x点进行一维搜索的方向。用Newton法求目标函数f(x)极小时是通过所谓求解方程组

关键词：三对角矩阵 Newton 正交矩阵算法

西方理论与中国研究──从《白银资本》谈几点看待西方理论架构的意见

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史学月刊 2002年第1期 98-106页

作者：张国刚吴莉苇南开大学历史系天津300071

《白银资本》目前在国内理论界享有盛誉，但也有人质疑其经济史内容的有效与可靠。此书一些结构性欠缺影响了其以“全球视野”为核心的论证体系的落实，从而削弱了此书的理论号召力。对此书理论价值的过誉或脱离其理论框架抨击所述内容... 详细信息

《白银资本》目前在国内理论界享有盛誉，但也有人质疑其经济史内容的有效与可靠。此书一些结构性欠缺影响了其以“全球视野”为核心的论证体系的落实，从而削弱了此书的理论号召力。对此书理论价值的过誉或脱离其理论框架抨击所述内容有失片面，但却颇能代表国内史学界认识西方史学理论的总体状况。看待西方理论时应注意几个问题：１、中国史学界的内部隔膜是导致对西方理论态度失衡的重要原因。２、推荐者应重视对所引介理论的实际研究效果作出可靠分析。３、引进批判西方中心论的理论时，不能轻视“现代化”对中国学术谱系的深刻影响。４、注意中西学术思维的差异，西方学者好以自我创新为主旨，中国学者惯以整体之力建构普适性理论。５、应认识到西方学术界得以活跃的观念性和制度性原因，并择善用之。

关键词：人质代表号召力理论界削弱落实全球视野《白银资本》西方史学史学界

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四面体超晶格中高温铁磁半导体的预测

Science China Materials 2024年第4期67卷 1225-1230页

作者：王亚奇孙华胜吴世海李盎万逸阚二军黄呈熙 MIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing Nanjing University of Science and TechnologyNanjing 10094China

铁磁(FM)半导体兼具半导体(如逻辑器件)和磁性材料(如记忆存储器)的优点,半个多世纪以来一直受到广泛关注.然而,铁磁半导体的发展受到候选材料稀缺以及居里温度低的阻碍.铁磁性通常在具有八面体配位的过渡金属化合物中被发现.而具有较... 详细信息

铁磁(FM)半导体兼具半导体(如逻辑器件)和磁性材料(如记忆存储器)的优点,半个多世纪以来一直受到广泛关注.然而,铁磁半导体的发展受到候选材料稀缺以及居里温度低的阻碍.铁磁性通常在具有八面体配位的过渡金属化合物中被发现.而具有较小晶体场分裂和较弱反铁磁(AFM)直接交换的四面体配位化合物可能是高温铁磁体的潜在候选者,但很少被探索.在这项工作中,我们提出了高温铁磁半导体可以在四面体配位超晶格(SL)中实现.在第一性原理计算的基础上,我们系统地研究了一系列MX/TMX (MX表示12-16,13-15或14-14族四面体半导体,TM表示3d过渡金属,X表示配体)超晶格.其中,SiC/CrC SL是一种稳定的铁磁半导体材料,具有0.363 eV的间接带隙和~935 K的高居里温度.此外,我们还探讨了Cr原子层的分布和层间磁耦合,预测了单轴应变引起了反铁磁到铁磁的相变.这些发现为实现四面体配位超晶格的高温铁磁半导体在未来自旋电子应用中开辟了新的机会.

关键词：过渡金属化合物高居里温度自旋电子晶体场分裂超晶格逻辑器件八面体配位候选者

Complex dynamics of functionally graded plates with thermal load in 1:2 internal resonance

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中国科学:技术科学 2010年第2期 218-218页

作者： DING Ran1 & wu ZhiQiang1,2 1 Department of Mechanics, Tianjin University, Tianjin 300072, China 2 State Key Laboratory of Engines, tianjing 310002, China

Complex dynamics of the simply-supported functionally graded (FG) rectangular plates with thermal load is investigated. Based on Reddy's third-order shear deformation theory and the von Karman nonlinear strain-displacement relations, ordinary differential equations (ODEs) of the plate's transversal oscillation are derived by using Hamilton's principle and Galerkin's approach. Solutions' classification of the equations in 1:2 internal resonance is analyzed. Particular results of a simply- supported aluminum-alumina rectangular FG plate are given. Effects of temperature and volume fraction on the responses' stabilities are discussed.

关键词： functionally graded materials thermal load 1 internal resonance solutions’ classification modal interactions

CLINICAL OBSERVATION AND EXPERIMENTAL STUDY ON THE TREATMENT OF CHRONIC PELVIC INFLAMMATION BY YISHEN HUOXUE DECOCTION AND CO_2, LASER POINT RADIATION

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World Journal of Acupuncture-Moxibustion 1992年第1期2卷 9-13页

作者： wu Gaoyuan Xu Dongqin, Zhao, Xiaomei, Liu Qing, tianjing College of Traditional Chinese Medicine, Tianjin, ChinaFu Rulian Kai Guiyun, Institute of Modern Optics, Nankai University, Tianjin, ChinaFu Guanghua, Tianjin Medical College for Medical Staffs, Tianjin, China

Authors observed clinically the treatment of Chronic Pelvic Inflammation of30 cases by YISHEN HUOXUE Decoction and CO2 Laser Point Radiation. In result, 16 cases（53.3%） were cured; 5 （16.7%） wtih obvious effect; 8 （26.7%） with good effect and 1 （3.3%） with-out effect. The total effective rate was 97.0%. The experimental research demonstrated that thiscomprehensive treatment had a definite effect on rat’s endometritis and could enhance cellularand humoral immunity.

关键词： immunity infertility LASER inflammation cured minutes muscular Radix uterine clinically

An Approximation Algorithm for the Stochastic Fault-Tolerant Facility Location Problem

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Journal of the Operations Research Society of China 2013年第4期1卷 511-522页

作者： Chenchen wu Dachuan Xu Jia Shu School of Mathematical Sciences Nankai UniversityTianjing 300071P.R.China Department of Applied Mathematics Beijing University of Technology100 PingleyuanChaoyang DistrictBeijing 100124P.R.China Department of Management Science and Engineering School of Economics and ManagementSoutheast UniversityNanjing 211189P.R.China

In this paper,we study a stochastic version of the fault-tolerant facility location *** exploiting the stochastic structure,we propose a 5-approximation algorithm which uses the LP-rounding technique based on the revised optimal solution to the linear programming relaxation of the stochastic fault-tolerant facility location problem.

关键词： Facility location problem Approximation algorithm LP rounding

Moving-object Detection Based on Shadow Removal and Prospect Reconstruction

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Moving-object Detection Based on Shadow Removal and Prospect...

Copper Matrix Composites Reinforced with Nanometer Alumina Particle

2012 International Conference on Artificial Intelligence and Soft Computing(ICAISC 2012)

作者： Wenping wu 1 Jing Shao 1 and Wei Guo 1 2 1 Dept. of Mathematics Science College Hebei University of Technology tianjing China 2 Mathematics and Information College Hebei Normal University Shijiazhuang China

In the process of moving target detection, moving objects and their shadows are often extracted both. It leads to the failure of moving target positioning, segmentation, tracking and classification in the moving-object detection. Thus the shadow removal is an important task in the intelligent monitoring system. In the process of shadow removal, using color features to detect shadow is easy to cause that some parts of the prospect with the same color as the shadow may be mistakenly removed, so that have an impact on the connection and integrity of the prospect. In this paper, in order to obtain a complete prospect as well as remove shadow, we propose a moving target detection algorithm based on shadow removal and prospect reconstruction. Our algorithm can effectively restore the prospect which is mistakenly removed as shadow, and the experimental results confirm our algorithm.

关键词： Background modeling Moving target segmentation Shadow detection Color feature Prospect reconstruction.

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Journal of Materials Science & Technology 1999年第2期15卷 143-146页

作者： wu, JJ Li, GB Zhang, Y Jiang, ZX Lei, TQ Hebei Univ Technol Dept Mat Sci & Engn Tianjing 300130 Peoples R China Harbin Inst Technol Harbin 150006 Peoples R China

The microstructure and properties of the oxide particle dispersion strengthened composite fabricated by internal oxidation method have been studied. Using nitrogen base atmosphere and a new process flow we can improve the quality of the MMCs and decrease the cost of the composites. The size of alumina is in the nanometer order of magnitude and the particles are well distributed. Under the condition of having good electrical conductivity, the composites have 1 to 2 times higher mechanical properties than those of pure Cu.

关键词： Metallic matrix composites

Fuzzy logic based coordinated control of battery energy storage system and dispatchable distributed generation for microgrid

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Journal of Modern Power Systems and Clean Energy 2015年第3期3卷 422-428页

作者： Haoran ZHAO Qiuwei wu Chengshan WANG Ling CHENG Claus Nygaard RASMUSSEN Department of Electrical Engineering Centre for Electric Power and EnergyTechnical University of Denmark2800 Kgs.LyngbyDenmark School of Electrical Engineering and Automation Tianjin UniversityTianjing 300072China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China Siemens Wind Power 2800 Kgs.LyngbyDenmark

Microgrid is a good option to integrate renewableenergy sources (RES) into power systems. Inorder to deal with the intermittent characteristics of therenewable energy based distributed generation (DG) units,a fuzzy-logic based coordinated control strategy of a batteryenergy storage system (BESS) and dispatchable DGunits is proposed for the microgrid management system(MMS). In the proposed coordinated control strategy, theBESS is used to minimize active power exchange at thepoint of common coupling of the microgrid for grid-connectedoperation, and is used for frequency control for islandoperation. The efficiency of the proposed controlstrategy was tested by case studies using DIgSILENT/PowerFactroy.

关键词： BESS Coordinated control Fuzzy-logic based control Microgrid