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On the Kahler-Ricci Flow on Projective Manifolds of General Type

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chinese Annals of Mathematics,Series B 2006年第2期27卷 179-192页

作者： Gang tian Zhou zhang Dedicated to the memory of Shiing-Shen chern

This note concerns the global existence and convergence of the solution for Kahler-Ricci flow equation when the canonical class, Kx, is numerically effective and big. We clarify some known results regarding this flow ... 详细信息

关键词： Geometric evolution equations Minimal model program

Existence and bifurcation of solutions for a double coupled system of Schrdinger equations

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Science china Mathematics 2015年第8期58卷 1607-1620页

作者： tian RuShun zhang ZhiTao Academy of Mathematics and Systems Science and HUA Loo-Keng Key Laboratory of MathematicsChinese Academy of Sciences

consider the following system of double coupled Schrodinger equations arising from Bose-Einstein condensates etc., where μ1, μ2 are positive and fixed; κ and β are linear and nonlinear coupling parameters respectively. We first use critical point theory and Liouville type theorem to prove some existence and nonexistence results on the positive solutions of this system. Then using the positive and non-degenerate solution to the scalar equation -△ω ＋ ω = ω3, ω ∈ Hr1（RN）, we construct a synchronized solution branch to prove that for/3 in certain range and fixed, there exist a series of bifurcations in product space R×Hr1（RN）×Hr1（RN） with parameter κ,

关键词： bifurcation system of Schr6dinger equations positive solution synchronized solution branch

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当前新药非临床安全性评价的趋势(英文)

中国药理学与毒理学杂志 2012年第1期26卷 1-3页

作者： charles c.zhang 戴仁科 Purdue Pharma LP CranburyNew Jersey 08512USA 中山珐玛斯医药科技有限公司广东中山528437

非临床药物安全性评价为新药的研发发挥了重要作用。人用药品注册技术要求国际协调会(IcH)新药研发指南M3(R2)是非临床药物安全性评价的方向性指导文献。正确的评价策略和相关毒理学研究应该一起综合考虑,以促进新药候选物高效、及时地... 详细信息

非临床药物安全性评价为新药的研发发挥了重要作用。人用药品注册技术要求国际协调会(IcH)新药研发指南M3(R2)是非临床药物安全性评价的方向性指导文献。正确的评价策略和相关毒理学研究应该一起综合考虑,以促进新药候选物高效、及时地向前发展,从而支持临床试验计划和市场登记进展。然而,随着发展成本增加和行业的竞争,毒性预测、动物模型和法规遵从性也是新药深入研发过程中非常重要的因素。此外,IcH其他指导文献,例如IcH S6和IcH S9,也是给新药深入研发带来冲击力很大的指导文献。因此,深入理解所有这些文献的本质意义对从事新药安全评价人员来说是很重要的,增强综合使用各方面总体知识的能力将促进新药深入研发更快、更好地实施。

关键词：非临床药物安全性 IcH指南毒理学新药研发小分子药物生物药物

Resource allocation based on sealed-bid auction algorithm in pervasive computing

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The Journal of china Universities of Posts and Telecommunications 2010年第1期17卷 85-92页

作者： zhang Lei tian Hui Beijing University of civil Engineering and Architecture~ Beijing 100044 China Key Laboratory of Universal Wireless commtmications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Pervasive computing, which requires applications composed of independent and distributed components, is an important domain for dynamic ubiquitous heterogeneous environment. However, one of the critical challenges it faces is resource allocation. To overcome the difficulty, enhanced universal service terminal （UST＋） is designed as a reflective middleware combined distributed components with particular features to achieve user goals. Moreover, a novel algorithm based on microeconomics is presented to resolve conflicting resource allocation and is implemented on top of the UST＋. Besides, an example outlines how this algorithm is used in pervasive computing, and the simulation results illustrate that the proposed mechanism can achieve high performance at low cost.

关键词： resource allocation conflict resolution UST+ sealed-bid auction

Stability Analysis of Sampled-data control System and Its Application to Electric Power Market

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chinese Journal of Electrical Engineering 2020年第1期6卷 61-70页

作者： tian zhang Shenping Xiao School of Electrical and Information Engineering Hunan University of TechnologyZhuzhou 412007China Key Laboratory for Electric Drive control and Intelligent Equipment of Hunan Province Zhuzhou 412007China

The stability of sampled-data systems is investigated using a new type of Lyapunov *** interval from the sampling point t_(k) to t_(k+1) is assumed to be a sampling *** fully utilizing the characteristic information on the whole sampling interval,a new two-sided closed-loop Lyapunov functional is proposed,which utilizes the information on both the intervals from the sampling point t to k_(t) and from t to t_(k+1).Based on the two-sided closed-loop Lyapunov functional and modified free-matrix-based inequality,a less conservative stability criterion is derived for a sampled-data control system,and three numerical examples are provided to verify the effectiveness and reduced conservativeness of the proposed ***,the proposed method is applied to solve the stability problem of electric power markets,and the practical significance of reducing the conservativeness is discussed.

关键词： Stability sampled-data control system two-sided closed-loop Lyapunov functional electric power market

Handling non-linearity in radar data assimilation using the non-linear least squares enhanced POD-4DVar

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Science china Earth Sciences 2017年第3期60卷 478-490页

作者： zhang Bin tian XiangJun zhang LiFeng SUN JianHua International center for climate and Environment Sciences(IccES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China college of Meteorology and Oceanography PLA University of Science and TechnologyNanjing 211101China collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Ley Laboratory of cloud-Precipitation Physics and Severe Storms(LAcS) Institute of Atmospheric PhysicsChinese Academy of Sciences Beijing 100029China

The Proper Orthogonal Decomposition(POD)-based ensemble four-dimensional variational(4DVar) assimilation method(POD4DEnVar) was proposed to combine the strengths of EnKF(i.e.,the ensemble Kalman filter) and 4DVar assimilation ***,a POD4DEnVar-based radar data assimilation scheme(PRAS) was built and its effectiveness was ***4 DEnVar is based on the assumption of a linear relationship between the model perturbations(MPs)and the observation perturbations(OPs);however,this assumption is likely to be destroyed by the highly non-linear forecast model or observation *** address this issue,using the Gauss-Newton iterative method,the nonlinear least squares enhanced POD4 DEnVar algorithm(referred to as NLS-4DVar) was ***,the PRAS was upgraded to form the NLS-4DVar-based radar data assimilation scheme(NRAS).To evaluate the performance of NRAS against PRAS,observing system simulation experiments(OSSEs) were conducted to assimilate reflectivity and radial velocity individually,with one,two,and three *** results demonstrated that the NRAS outperformed PRAS in improving the initial condition and the forecasting of model variables and *** NRAS,with a smaller number of iterations,can yield a convergent *** contrast to the situation when assimilating radial velocity,the advantages of NRAS over PRAS were more obvious when assimilating reflectivity.

关键词： Data assimilation Non-linearity Gauss-Newton NRAS PRAS Radar reflectivity Radial velocity

PcA weight and Johnson transformation based alarm threshold optimization in chemical processes

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chinese Journal of chemical Engineering 2018年第8期26卷 1653-1661页

作者： Wende tian Guixin zhang Xiang zhang Yuxi Dong college of chemical Engineering Qingdao University of Science & Technology

To alleviate the heavy load of massive alarm on operators, alarm threshold in chemical processes was optimized with principal component analysis(PcA) weight and Johnson transformation in this paper. First, few variables that have high PcA weight factors are chosen as key variables. Given a total alarm frequency to these variables initially, the allowed alarm number for each variable is determined according to their sampling time and weight factors. Their alarm threshold and then control limit percentage are determined successively. The control limit percentage of non-key variables is determined with 3σ method alternatively. Second, raw data are transformed into normal distribution data with Johnson function for all variables before updating their alarm thresholds via inverse transformation of obtained control limit percentage. Alarm thresholds are optimized by iterating this process until the calculated alarm frequency reaches standard level(normally one alarm per minute). Finally,variables and their alarm thresholds are visualized in parallel coordinate to depict their variation trends concisely and clearly. case studies on a simulated industrial atmospheric-vacuum crude distillation demonstrate that the proposed alarm threshold optimization strategy can effectively reduce false alarm rate in chemical processes.

关键词： Alarm threshold chemical process PcA Johnson transformation Variable weight

Fluorinated poly(p-triphenylene isatin) anion exchange membranes based on hydrophilic hydroxyl side chain modulation for fuel cells

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Journal of Energy chemistry 2025年第1期100卷 702-709页

作者： Yiman Gu Yanchao zhang Zhanyu Li Yijia Lei Baozeng Sun Xiaoyu Yu Zhe Wang college of chemistry and Life Science Changchun University of Technology college of chemical Engineering Changchun University of Technology School of Materials Science and Engineering Changchun University of Technology Key Laboratory of Advanced Functional Polymer Membrane Materials of Jilin Province

The development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes （AEMs） has been widely ***,the question of the“trade-off”between AEM ionic conductivity and dimensional stability remains *** strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being ***,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone （x=40,50,and 60） into the main chain of poly（p-terphenylene isatin）.Because fluorinated groups have excellent hydrophobicity,hydrophilic hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation *** results show that PTI-PTF50-NOH AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali stability under the combined effect of *** has an ionic conductivity of 133.83 mS cm-1at 80°*** addition,the OH-conductivity remains at 89%of the initial value at 80°c and 3 M KOH for 1056 h of *** cell polarization curve based on PTI-PTF50-NOH shows a power density of 734.76 mW cm-2at a current density of 1807.7 mA cm-2.

关键词： Anion exchange membranes Poly(p-terphenylene isatin) Hydrophilic-hydrophobic phase separation Fluorinated group

An Analytical Analysis of Relaxation States in Toroidal Plasma with a coaxial Helicity Injection

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中国核科技报告 1999年第S4期 387-388页

作者： D.Zhou c.zhang Institute of Plasma Physics chinese Academy of Science P.O.Box 1126 Hefei 230031 P.R.china

The Euler-Lagrange equations are derived from the principle of minimum dissipation to represent the relaxation state in toroidal plasma with a coaxial helicity

关键词： An Analytical Analysis of Relaxation States in Toroidal Plasma with a coaxial Helicity Injection