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Generalized gradient projection neural networks for nonsmooth optimization problems

Science China(Information Sciences) 2010年第5期53卷 990-1005页

作者： LI GuoCheng 1 , SONG ShiJi 2 ? & WU Cheng 2 1 department of Mathematics, Beijing Information Science and Technology University, Beijing 100192, China 2 department of Automation, Tsinghua University, Beijing 100084, China 1. department of Mathematics Beijing Information Science and Technology University Beijing 100192 China2. Department of Automation Tsinghua University Beijing 100084 China

Generalized gradient projection neural network models are proposed to solve nonsmooth convex and nonconvex nonlinear programming problems over a closed convex subset of R n . By using Clarke’s generalized gradient, the neural network modeled by a differential inclusion is developed, and its dynamical behavior and optimization capabilities both for convex and nonconvex problems are rigorously analyzed in the framework of nonsmooth analysis and the differential inclusion theory. First for nonconvex optimization problems, the quasi convergence results similar to those achieved by previous work are proved. For convex optimization problems, the global convergence results are proved, i.e. any trajectory of the neural network converges to an asymptotically stable equilibrium point, which is an optimal solution of the primal problem whenever it exists. This result remains valid even if the initial condition is chosen outside the feasible set. In addition, an asymptotic control result involving a Tykhonov like regularization shows that any trajectory of the revised neural network can be forced to converge toward a particular optimal solution of the primal problem. Finally, two simulation optimization algorithms for solving the optimization and control problems are designed respectively, and three typical simulation experiments are illustrated to present the accuracy and efficiency of theoretical convergence results of this paper.

关键词： nonsmooth optimization problem generalized gradient projection networks differential inclu sions convergence

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Analysis of the Current Industrial Growth Pattern

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China & World Economy 2003年第5期11卷 44-50页

作者： Yang Jianlong, research Office of the Industrial Economy department, State council development research Center.

The process of economic growth and industrial structure upgrading is essentially a process of the formation and replacement of high growth industries. After steady operations over the past three years, China’s industrial growth structure has undergone significant changes, with a number of industries (automobile, machine-building, real estate and tourism) accelerating to become a major force in fueling national economic growth. Whether or not the high growth of these industries will persist so that they become pillar industries in the new round of growth is the key to determining both the nature and the formation of the engine of the new round of growth.

关键词： of in on for is as Analysis of the Current Industrial Growth Pattern that

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碳酸盐岩储层欠平衡钻井技术难点与对策

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天然气工业 2004年第12期24卷 77-79页

作者：侯绪田中国石化勘探开发研究院德州石油钻井研究所

欠平衡钻井技术具有很强的地区适应性特点 ,不同的储层特性决定了不同的欠平衡钻井方式和技术特色。碳酸盐岩储层井眼溶洞、裂隙发育、置换性恶性漏失是欠平衡钻井工艺不容忽视的技术难点。文章在分析新疆塔北油田奥陶系碳酸盐岩储层特... 详细信息

欠平衡钻井技术具有很强的地区适应性特点 ,不同的储层特性决定了不同的欠平衡钻井方式和技术特色。碳酸盐岩储层井眼溶洞、裂隙发育、置换性恶性漏失是欠平衡钻井工艺不容忽视的技术难点。文章在分析新疆塔北油田奥陶系碳酸盐岩储层特点的基础上 ,对碳酸盐岩储层欠平衡钻井工艺存在的设备配套的多样化要求、欠压值设计难、井底负压控制难、置换性漏失时压井难和强行完井难等技术难点进行了详细分析。根据置换性漏失、强行完井施工等要求对井口、井下设备在标准配置的基础上进行了调整 ,依据碳酸盐岩储层、探井施工的特点提出了循环渐进、灵活的欠压值控制方法 ,改进的反循环压井技术比平推压井方法减少了压井作业对储层带来的伤害。

关键词：欠平衡钻井技术碳酸盐岩储层欠压值压井完井漏失储层特性裂隙发育奥陶系反循环

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Sediment texture and grain-size implications: the Changjiang subaqueous delta

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Acta Oceanologica Sinica 2009年第4期28卷 38-49页

作者： ZHANG Rui WANG Yaping GAO Jianhua PAN Shaoming MOE Key Laboratory of coastal and Island development Nanjing University Nanjing 210093 China department of coastal Ocean Science Nanjing University Nanjing 210093 China

Sediment cores were collected from the subaqueous delta of the Changjiang Estuary. Sediment grain-size profiles and their fractal dimensions were analyzed, to elucidate responses to long-term sedimentary processes. In addition, the environmental sensitive populations of grain size have been extracted. The sediment cores can be divided into two parts, according to the sedimentary structures present. The upper part （0-12 cm） is interpreted as being the active layer, which is influenced frequently by changes in the short-term hydrodynamic environment. The lower part extends from a depth of 12 cm, to the bottom of the core. The pattern of fluctuation is linked to sediment grain size. Moreover, two grain-size sensitive populations can be identified. The fine sensitive population is 6.0-7.2 μm, which is a similar grain size to the suspended sediment from up-river. The coarse sensitive population varies from 40.7 to 57.5 μm, revealing complex changes. Thus, the riverine inputs from the Changjiang River may be an important source, which contributes to seasonal fluctuations of grain-size distribution, over the area. The sediments, with grain-sizes ranging from 0.9 to 20.3 μm, are characterised by self-similar in the fractal non-scale region. The fraetal dimension is eonsistant with the grain-size parameter varatioins, which could be used as a replacement index to reveal and reconstruct the sedimentary environmental evolution.

关键词： grain size sedimentary environment fractal dimension grain-size sensitive populations Changjiang Estuary

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coMPARISON OF ScoURS IN FRONT OF VERTICAL BREAKWATERS DUE TO REGULAR AND IRREGULAR WAVES

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Journal of Hydrodynamics 2000年第1期12卷 1-7页

作者： Gao Xue ping department of Civil and Environmental Engineering, Faculty of Engineering, Ehime University, 3 Bunkyo cho, Matsuyama 790 77, JapanKunimitsu Inouchi Center for cooperative research and development, Ehime University, 3 Bunkyo cho, Mats Ehime Univ Matsuyama Japan

In this paper the scours of sand bed due to regular and irregular waves in front of vertical breakwaters, such as scouring patterns, scouring mechanisms, etc., are investigated. Thereby, the scours under the action of... 详细信息

关键词： scours regular waves irregular waves

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高含硫地质环境钻井硫化氢气侵规律研究

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石油学报 2008年第4期29卷 601-604页

作者：石晓兵甘一风钟水清熊继有张仕强西南石油大学油气藏地质及开发工程国家重点实验室四川成都610500 中国石油新疆石油公司勘探开发研究院新疆克拉玛依834000 中国石化西南分公司川西采输处四川德阳618000

针对硫化氢的特殊物性,研究了硫化氢组分、气体偏差因子、硫化氢黏度等重要的物性参数对气侵两相流的影响。运用气液两相流的原理和方法,建立了硫化氢气侵时环空气液两相流流动模型,研究了硫化氢气侵时井底压力和井筒压力的特征及变化规... 详细信息

针对硫化氢的特殊物性,研究了硫化氢组分、气体偏差因子、硫化氢黏度等重要的物性参数对气侵两相流的影响。运用气液两相流的原理和方法,建立了硫化氢气侵时环空气液两相流流动模型,研究了硫化氢气侵时井底压力和井筒压力的特征及变化规律,并用实例对理论模型进行了验证,进而分析了气侵时钻井液密度、钻井液黏度、井口回压、井底气侵速率等重要参数对井底压力的影响规律。在确定钻井液附加密度时,应充分考虑硫化氢气侵对井底压力和井筒动压的影响规律,其结果会更加合理。

关键词：高含硫地层钻井硫化氢气侵气-液两相流流动模型压力控制

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Molecular Targets of combined Natural Antioxidants Against Diabetes in Streptozotocin-induced Diabetic Mice

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Chemical research in Chinese Universities 2012年第1期28卷 96-102页

作者： SONG Yang1,2, GAO Zhong-li2, DU Zhen-wu1, PIAO Song-lan1, WANG Ling-ling1, WANG Qing3 and ZHANG Gui-zhen1 1. Central research department, 2. department of Orthopaedics, 3. department of Endocrinology, China-Japan Union Hospital of Jilin University, Changchun 130033, P. R. China Jilin Univ China Japan Union Hosp Dept Endocrinol Changchun 130033 Peoples R China Jilin Univ China Japan Union Hosp Cent Res Dept Changchun 130033 Peoples R China Jilin Univ China Japan Union Hosp Dept Orthopaed Changchun 130033 Peoples R China

Natural antioxidants, due to the different chemical structures and their unique biological protection effects on islet cell, have been received much attention in applied chemistry field for developing a new diabetic drug. However, the molecular targets of the islet cell protection have been remained obscure. For investigating molecular targets of combined natural antioxidant’s（CNA） roles in against diabetes, type 1 diabetic mouse model was made by multiple injection of low doses of streptozotocin into C57BL mice. Two combinations of natural antioxidants were orally supplemented to the mice. Blood glucose level, glutathione peroxidase（GSH-Px） and superoxide dismutase （SOD） activities, and malondialdehyde（MDA） contents were measured via biochemical assays. Tumor necrosis factor α（TNF-α）, interferon γ（IFN-γ） and Interleukin-12（IL-12） in CD4＋ Peripheral blood mononuclear cells（PBMC） were evaluated with flow cytometry（FCM）. In situ hybridization（ISH） and immunohistochemistry（IHC） were used to detect insulin gene expression. The results demonstrate both the combinations significantly： increased GSH-px and SOD, but decreased MDA levels in pancreas（p〈0.05―0.01）; up-regulated insulin expression at both mRNA and protein levels in islet cells（p〈0.05―0.01）; down-regulated TNF-α and IL-12 expression in PBMC（p〈0.05―0.01）. Our data suggest that the CAN may regulate multiple key molecular targets related to β cell function, including reduction of oxidative stress and pre-inflammatory cytokines, and upregulate insulin gene expression to reduce the development of diabetes.

关键词： combined natural antioxidant Diabetes Insulin gene expression Oxidative stress Pro-inflammatory cytokine

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Density-functional formula for strongly correlated systems

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Progress in Natural Science:Materials International 2005年第5期15卷 395-401页

作者： WANG Huaiyu1*, HAN Rushan2 and CHEN Nanxian1(1. department of Physics, Tsinghua University, Beijing 100084, China 2. department of Physics, Peking University, Beijing 100871, China) department of Physics Tsinghua University Beijing 100084 China department of Physics Peking University Beijing 100871 China

Density functional method is applied for strongly correlated systems. Based on the assumption that the systems are composed of electrons in singly-occupied orbitals and those in doubly-occupied orbitals, a set of self-consistent equations are obtained by standard variation procedure. The equations consist of two parts. One part is to solve the wave functions of the electrons in singly-occupied orbitals and the other is to solve the wave functions of the electrons in doubly-occupied orbitals. The physical meanings of the terms appearing in the equations are discussed.

关键词： density-functional theory strongly correlated systems doubly-occupied orbital two-particle wave function self-consistent equations.

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Averting Financial Risks

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ChinAfrica 2012年第2期4卷 36-37页

作者： Wei Jianing,Deputy Director of the department of Macroeconomic research of the development research Center of the State council,

THE Chinese economy faces three major risks： burst of real estate bubbles, risks of local gov ernment financing platforms and split of capital chains for private lending.

关键词： Averting Financial Risks

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Diagenesis and Restructuring Mechanism of Oil and Gas Reservoir in the Marine Carbonate Formation,Northeastern sichuan:A Case Study of the Puguang Gas Reservoir

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Acta Geologica Sinica(English Edition) 2009年第6期83卷 1173-1181页

作者： DU Chunguo1, 2, WANG Jianjun1, ZOU Huayao2, ZHU Yangming3 and WANG Cunwu4 1 research Institute of Petroleum Exploration and development, Beijing 100034, China 2 Petroleum University of China, Beijing 102249, China 3 department of Earth Science, Zhejiang University, Hangzhou 310027, China 4 Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, China Faculty of Earth Resources China University of Geosciences Wuhan 430074 China

Based on the technology of balanced cross-section and physical simulation experiments associated with natural gas geochemical characteristic analyses, core and thin section observations, it has been proven that the Puguang gas reservoir has experienced two periods of diagenesis and restructuring since the Late Indo-Chinese epoch. One is the fluid transfer controlled by the tectonic movement and the other is geochemical reconstruction controlled by thermochemical sulfate reduction (TSR). The middle Yanshan epoch was the main period that the Puguang gas reservoir experienced the geochemical reaction of TSR. TSR can recreate the fluid in the gas reservoir, which makes the gas drying index higher and carbon isotope heavier because C2+ (ethane and heavy hydrocarbon) and 12C (carbon 12 isotope) is first consumed relative to CH4 and 13C (carbon 13 isotope). However, the reciprocity between fluid regarding TSR (hydrocarbon, sulfureted hydrogen (H2S) , and water) and reservoir rock results in reservoir rock erosion and anhydrite alteration, which increases porosity in reservoir, thereby improving the petrophysical properties. Superimposed by later tectonic movement, the fluid in Puguang reservoir has twice experienced adjustment, one in the late Yanshan epoch to the early Himalayan epoch and the other time in late Himalayan epoch, after which Puguang gas reservoir is finally developed.

关键词： diagenesis and restructuring mechanism marine carbonate formation thermochemical sulfate reduction Puguang gas reservoir

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