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李家峡拱坝水平位移变化规律异常成因分析

水电能源科学 2010年第7期28卷 60-63,174页

作者：彭妍娄一青虞鸿汪亚超河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098 温州市水利局浙江温州325000

针对李家峡大坝垂线监测资料分析中发现的异常现象,对其进行物理成因分析,建立位移统计模型分析了其主要影响因素,并通过对李家峡大坝的大量模拟研究建立了三维有限元模型,在多模型、多工况、多种材料参数组合计算的基础上,分析了大坝... 详细信息

针对李家峡大坝垂线监测资料分析中发现的异常现象,对其进行物理成因分析,建立位移统计模型分析了其主要影响因素,并通过对李家峡大坝的大量模拟研究建立了三维有限元模型,在多模型、多工况、多种材料参数组合计算的基础上,分析了大坝变形异常成因,查清了水平位移变化规律异常的原因。

关键词：李家峡拱坝水平位移变化规律物理成因分析 Arch Dam 三维有限元模型主要影响因素监测资料分析大坝变形异常现象异常成因模型分析模拟研究多种材料参数组合多模型多工况统计计算

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因子分析法在绕坝渗流监测资料分析中的应用

水电能源科学 2010年第5期28卷 62-64,28页

作者：毕奇龙刘星徐波方春晖河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

针对大坝安全监控中多个影响量与效应量间的非线性关系拟合难度较大,基于因子分析法,结合水口大坝绕坝渗流的监测资料对各影响因素的因子组成进行了分析,通过研究原始变量的内部关系及绕坝渗流观测孔的布置方式,确定了影响绕坝渗流的主... 详细信息

针对大坝安全监控中多个影响量与效应量间的非线性关系拟合难度较大,基于因子分析法,结合水口大坝绕坝渗流的监测资料对各影响因素的因子组成进行了分析,通过研究原始变量的内部关系及绕坝渗流观测孔的布置方式,确定了影响绕坝渗流的主要因素,据此揭示了绕坝渗流与各影响因素间的关系及时空分布规律。

关键词：大坝安全监测因子分析法绕坝渗流多元统计分析

基于HyperMesh软件的复杂结构有限元建模

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水电能源科学 2010年第8期28卷 100-102,105页

作者：彭妍娄一青汪亚超徐宝松河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098 温州市水利局浙江温州325000

针对结构复杂的大坝有限元结构分析中常需在已有HyperMesh格式有限元模型上增加某些附属混凝土结构,以李家峡双曲拱坝为例,采用HyperMesh软件中的Geom和Tool等子面板建立新增附属结构的几何模型,并剖分为三维有限元模型,进而与AutoCAD... 详细信息

针对结构复杂的大坝有限元结构分析中常需在已有HyperMesh格式有限元模型上增加某些附属混凝土结构,以李家峡双曲拱坝为例,采用HyperMesh软件中的Geom和Tool等子面板建立新增附属结构的几何模型,并剖分为三维有限元模型,进而与AutoCAD软件进行比较。结果表明,利用HyperMesh软件对复杂结构进行补充修改几何模型,可大幅提高建模效率。

关键词： HyperMesh AutoCAD软件结构有限元建模 Software Based Complex Structure 三维有限元模型几何模型有限元结构分析混凝土结构双曲拱坝结构复杂建模效率复杂结构附属结构补充修改软件中李家峡剖分面板

High Energy Micro-arc Alloying of ZM5 Mg Alloy by Mg-Y Electrode under Liquid

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稀有金属材料与工程 2011年第S4期40卷 181-184页

作者： Chen Changjun,Zhang Min,Su Yanzhan,Zhang Shichang,Zhou Jialin Key Laboratory for Ferrous Metallurgy and resources utilization of Ministry of Education,Laser Processing research center,College of Materials and Metallurgy,Wuhan university of Science& Technology,Wuhan 430081,china Wuhan Univ Sci &Technol Laser Proc Res Ctr Key Lab Ferrous Met & Resources Utilizat Minist EducColl Mat & Met Wuhan 430081 Peoples R China

High-energy micro-arc alloying (HEMAA) is a consumable electrode,micro-welding process which uses electrical pulses that are typically three orders of magnitude shorter than in other pulse welding *** durations of a few microseconds combined with pulse frequencies in the 0.1 to 2-kilohertz range thus allow substrate heat dissipation over ～99% of the duty cycle while heating only about 1%.The cooling rates may approach 105 to 106 ℃/s,depending on *** obtained coating can produce unique corrosion and tribological *** require no special surface preparation and nearly any metal,alloy or cermets can be applied to metal *** paper details experimental results when alloying Mg base alloy ZM5,using Mg-Y electrodes with a water-based dielectric *** morphology and the composition of the alloying was analyzed by scanning electron microscope(SEM) and energy dispersive X-ray analysis(EDX).At the discharge energies employed,a thin recast layer thickness and rougher layers were formed on the *** layers were in general *** analysis showed that the Y transferred from the solid electrodes to the workpiece surface.

关键词： high-energy micro-arc alloying (HEMAA) surface alloying/modification Mg alloy Mg-Y

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宁夏引黄提水灌区水价测算方法

水电能源科学 2011年第6期29卷 140-142页

作者：任杰宁夏大学土木与水利工程学院宁夏银川750021 宁夏节水灌溉与水资源调控工程技术研究中心宁夏银川750021 旱区现代农业水资源高效利用工程研究中心宁夏银川750021

为有效提高提水灌区水资源利用效率,基于水价计算及水费收取问题,以宁夏引黄灌区为例,依据《水利工程供水价格管理办法》,采用完全成本定价法评价了水资源价值,并测算了宁夏某灌区水价,为灌区水价管理提供了依据。

关键词：提水灌区水价计算方法宁夏

Surface Top Graphology,Corrosion and Microhardness of Oxygen Diffusion Hardened Pure Titanium Alloy TA4 after Laser Surface Melting

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稀有金属材料与工程 2011年第S4期40卷 185-189页

作者： Chen Changjun,Zhang Min,Su Yanzhan,Zhang Shichang,Zhou Jialin Key Laboratory for Ferrous Metallurgy and resources utilization of Ministry of Education,Laser Processing research center,College of Materials and Metallurgy,Wuhan university of Science& Technology,Wuhan 430081,china Wuhan Univ Sci & Technol Laser Proc Res Ctr Key Lab Ferrous Met & Resources Utilizat Minist EducColl Mat & Met Wuhan 430081 Peoples R China

In the oxygen diffusion hardened condition,untreated and laser surface melted pure titanium alloy (TA4) by Nd:YAG pulsed laser,are hardened at temperatures of 650 to 700℃ with the end result being a passive,mechanically stable,abrasion resistant oxide ceramic rutile surface *** thickness of this surface layer depends on the time,temperature,and the microstructure of the Ti *** paper describes the results of x-ray diffraction analysis,scanning electron microscope (SEM),microhardness measurements,and corrosion resistance measurements of hardened pure and laser treated Ti *** oxygen diffusion hardened titanium alloy after laser surface melted samples (L-TA4) had a more pronounced grain structure and significantly higher roughness values than the untreated pure TA4 (U-TA4)*** L-TA4 samples also exhibited at least equivalent corrosion behavior and a definite increase in surface hardness compared to the U-TA4 *** results of this work suggest that laser surface melting plays a key role for effective oxygen diffusion hardening at 650-700℃ for pure and laser treated pure Ti alloys.

关键词： oxygen diffusion harden (ODH) titanium alloy laser surface melting corrosion

engineering of drug nanoparticles by HGCP for pharmaceutical applications

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Particuology 2008年第4期6卷 239-251页

作者： Ting-Ting Hua, Jie-Xin Wanga, Zhi-Gang Shena, Jian-Feng Chena,b, a Key Lab for Nanomaterials, Ministry of Education, Beijing university of Chemical Technology, Beijing 100029, china b research center of Ministry of Education for High Gravity engineering and Technology, Beijing university of Chemical Technology, Beijing 100029, china [a] Key Lab for Nanomaterials Ministry of Education Beijing University of Chemical Technology Beijing 100029 China [b] research center of Ministry of Education for High Gravity engineering and Technology Beijing University of Chemical Technology Beijing 100029 China

This paper reviews our work on the fundamental principles of high gravity controlled precipitation (HGCP) technology, and its applications in the production of drug nanoparticles, which was carried out in a rotating packed bed (RPB). Several kinds of drug nanoparticles with narrow particle size distributions (PSDs) were successfully prepared via HGCP, including the 300-nm Cefuroxime Axetil (CFA) particles, 200–400-nm cephradine particles, 500-nm salbutamol sulfate (SS) particles (100 nm in width), and 850-nm beclomethasone dipropionate (BDP) particles, etc. Compared to drugs available in the current market, all the drug nanoparticles produced by HGCP exhibited advantages in both formulation and drug delivery, thus improving the bioavailability of drugs. HGCP is essentially a platform technology for the preparation of poorly water-soluble drug nanoparticles for oral and injection delivery, and of inhalable drugs for pulmonary delivery. Consequently, HGCP offers potential applications in the pharmaceutical industry due to its cost-effectiveness, efficient processing and the ease of scaling-up.

关键词： High gravity controlled precipitation Rotating packed bed Drug nanoparticle Poorly water-soluble drug Inhalable drug

Energy-efficient power allocation for selfish cooperative communication networks using bargaining game

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Science china(Information Sciences) 2012年第4期55卷 795-804页

作者： DING EnJie 1,ZHANG GuoPeng 1,LIU Peng 1 & YANG Kun 2 1 CUMT-IoT Perception Mine research center,china university of Mining and Technology,Xuzhou 221116,china 2 School of Computer Science and Electronic engineering,university of Essex Wivenhoe Park,Colchester Essex,CO4 3SQ,UK 1. CUMT-IoT Perception Mine research center China University of Mining and Technology Xuzhou 221116 China2. School of Computer Science and Electronic Engineering University of Essex Wivenhoe Park Colchester Essex CO4 3SQ UK

In commercial networks,user nodes operating on batteries are assumed to be selfish to consume their energy solely to maximize their own benefits,e.g.,data *** this paper,we propose a bargaining game to perform the power allocation for the selfish cooperative communication *** our system,two partner nodes can act as a source as well as a relay for each other,and each node is with an energy constraint to transmit one *** a selfish node is willing to seek cooperative transmission only if the data rate achieved through cooperation will not lower than that achieved through noncooperation by using the same amount of *** energy-efficient power allocation problem can be modeled as a cooperative *** proved that there exists a unique Nash bargaining solution (NBS) for the game by verifying that the game is indeed a bargaining ***,the two objectives,i.e.,system efficiency and user fairness specified in the selfish networks can be *** results show that the NBS scheme is efficient in that the performance loss of the NBS scheme to that of the maximal overall rate scheme is small while the maximal-rate scheme is *** simulation results also show that the NBS result is fair in that both nodes could experience better performance than they work independently and the degree of cooperation of a node only depends on how much contribution its partner can make to improve its own performance.

关键词： cooperative communication energy efficiency resource allocation cooperative game theory Nash bargaining solution

Spontaneous chiral-symmetry breaking of lattice QCD with massless dynamical quarks

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Science china(Physics,Mechanics & Astronomy) 2007年第1期50卷 6-14页

作者： LUO XiangQian Department of Physics,School of Physics and engineering,Sun Yat-Sen university,Guangzhou 510275,china 1. Department of Physics School of Physics and Engineering Sun Yat-Sen University Guangzhou 510275 China

One of the most challenging issues in QCD is the investigation of spontaneous chiral-symmetry breaking, which is characterized by the non-vanishing chiral condensate when the bare fermion mass is zero. In standard methods of the lattice gauge theory, one has to perform expensive simulations at multiple bare quark masses, and employ some modeled functions to extrapolate the data to the chiral limit. This paper applies the probability distribution function method to computing the chiral condensate in lattice QCD with massless dynamical quarks, without any ambiguous mass extrapolation. The results for staggered quarks indicate that this might be a promising and efficient method for investigating the spontaneous chiral-symmetry breaking in lattice QCD, which deserves further investigation.

关键词： lattice QCD spontaneous chiral-symmetry breaking dynamical quarks