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关于分离变量法的一个注记

物理学报 2004年第6期53卷 1639-1642页

作者：李德生张鸿庆大连理工大学应用数学系

从B cklund变换出发 ,利用Cole Hopf变换 ,一些有重要物理意义的 (2 +1 )维非线性演化方程 (组 )被简化为具有两个分别关于 (x,t) ,(y,t)的任意函数的单个线性偏微分方程 .通过对该方程解的研究 ,获得了原方程一些新的精确解 .其中。

关键词：分离变量法 Backlund变换 Cole-Hopf变换非线性演化方程精确解

CODING-ORIENTED MULTI-VIEW VIDEO COLOR CORRECTION

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Journal of Electronics(china) 2008年第6期25卷 721-727页

作者： Shao Feng Jiang Gangyi Yu Mei Chen Xiexiong Faculty of Information Science and Engineering Ningbo University Ningbo 315211 China National Key Lab of Software New technology Nanjing University Nanjing 210093 China department of Information and Electronics Engineering Zhejiang University Hangzhou 310027 China

Color inconsistency between views is an important problem to be solved in multi-view video applications, such as free viewpoint television and other three-dimensional video systems. In this paper, by combining with multi-view video coding, a coding-oriented multi-view video color correction method is proposed. We first separate foreground and background in first Group Of Pictures （GOP） by using SKIP coding mode. Then by transferring means and standard deviations in backgrounds, color correction is performed for each frame in GOP, and multi-view video coding is performed and used to renew the backgrounds. Experimental results ances in color correction and multi-view video show the proposed method can obtain better performcoding.

关键词： Multi-view video Color correction Multi-view video coding Background

Dispersion of ultrafine alumina in modifier solution ——the role of polar interfacial interaction

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Journal of Central South University of technology 2001年第1期8卷 18-23页

作者： HU Yue hua 1,QIU Guan zhou 1,J.D.Miller 2 (1.department of Mineral Engineering, Central South University, Changsha 410083. china 2.department of Metallurgical Engineering, University of Utah, 412 WBB, Salt Lake City, UT 84112, USA) department of Mineral Engineering Central South University Changsha China department of Metallurgical Engineering University of Utah 412 WBB Salt Lake City USA

Dispersion of ultrafine alumina suspension is examined by using particle size analyzer. The zeta potential and contact angle measurements were used to discuss the electrokinetic behavior and surface wettability of alumina in modifier solution, and to calculate the electrostatic interaction forces and interfacial interaction forces between alumina particles. The aggregation of ultrafine alumina occurs near its PZC. Addition of modifier increases the zeta potential of alumina and its surface hydrophilicity, resulting in increase of electrostatic and hydration repulsion. It makes the suspension of ultrafine alumina completely dispersed. The average particle size of the suspension is decreased from 1.73.μm in absence of modifier to 0.8 μm in the presence of tripolyphosphate. According to polar interfacial interaction approach, the hydration forces responsible for the stability of alumina suspension in the presence of modifier have also been obtained. The extended DLVO theory is successful to describe the dispersion behavior of ultrafine alumina in modifier solution.

关键词： dispersion alumina modifier polar interfacial interaction extended DLVO theory

Computer System Reliability Allocation Method and Supporting Tool

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Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 505-510页

作者： Ben Ke\|rong 1, Yan Jiong 2, Wang Ji 2 1 department of Computer Science, Naval University of Engineering, Wuhan 43.03., china Software Engineering Key Lab.,Wuhan University,Wuhan 43.072, china 2 department of Computer Science, National Universit department of Computer Science Naval University of Engineering Wuhan China Software Engineering Key Lab. Wuhan University Wuhan China department of Computer Science National University of Defence Technology Changsha China

This paper presents a computer system reliability allocation method that is based on the theory of statistic and Markovian chain,which can be used to allocate reliability to subsystem, to hybrid system and software mo... 详细信息

关键词： software Reliability reliability allocation method supporting tool

Principle　analysis　and　electromagnetic　design　of　half－bridge　commutating　circuit　for　thyristor　arc　welding　inverter

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china Welding 1996年第1期5卷 10-21页

作者： LI Zhongyou LI Qiaomin YANG Min LI Qingbin and YANG Youli(Welding department. Shandong University of technology. Ji’nan. 250014) Welding department Shandong University of Technology Ji'nan 250014 ***

A novel theory of the commutating process of half/bridge thyristor are welding inverter is presented. According to the characteristic of its typical primary current pulse, a commutating process can be divided into three stages. ie.. front-edge wave-head stage and back-edge *** equivalent circuits of each stage are presented respectively. For wave-head stage, the differential equation about the voltage across commutating capacitor has been set up with the initial condition of nonzero-current and nonzero-voltage. and its solutions are completely in accord with the practically measured waveforms. For front and back edge stages, the theory of current shifting on constant magnetic condition is introduced. The process, in which the inverse voltage across commutating capacitor is formed, and the rule, according to which the inverse voltage *** discussed. In addition. each. special operating state is studied carefully and a reasonable design state is determined. By T-type equivalent circuit in the design. state. the fundamental formulas for accurate engineering design are derived. Finally. two design cases are given.

关键词： RLCU equivalent circuit current shifting inverse voltage forming design State

Empirical Analysis of Factors Influencing Compensation for Non-commercial Forests under CVM

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Asian Agricultural Research 2012年第7期4卷 1-6,12页

作者： ZHANG Mei College of Economics and Trade,Zhongkai University of Agriculture and Engineering,guangzhou 510225,china

Based on non-commercial forests in Kunming City,this article conducts survey of 506 households in Kunming City to evaluate their willingness to pay ecological benefit of non-commercial forests,using Contingent Valuation Method(CVM);to analyze factors influencing their willingness to compensate for non-commercial forests,using multivariate statistical analysis *** results show that income,educational level, housing ownership,outdoor exercise time,whether to be concerned about environmental problems,frequency of obtaining forest-related information monthly and whether understanding non-commercial forests or not,are the most principal factors influencing willingness to pay.

关键词： Non-commercial forests Ecological benefit compensa

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逆流色谱溶质出峰顺序的预测

色谱 2002年第6期20卷 526-529页

作者：周玉杰陈福明李总成清华大学化工系北京100084 深圳清华大学研究院广东深圳518057

根据逆流色谱保留方程可知,溶质的出峰顺序主要取决于其在互不混溶的两液相间分配系数的大小顺序。以饱和及不饱和脂肪酸乙酯、2,4 二硝基苯胺基脂肪醇和对硝基苯基葡萄糖甙等结构较为简单、极性差别较大的溶质系列为研究对象,应用修正... 详细信息

根据逆流色谱保留方程可知,溶质的出峰顺序主要取决于其在互不混溶的两液相间分配系数的大小顺序。以饱和及不饱和脂肪酸乙酯、2,4 二硝基苯胺基脂肪醇和对硝基苯基葡萄糖甙等结构较为简单、极性差别较大的溶质系列为研究对象,应用修正的通用基团活度系数(UNIFAC)(Dortmund)模型,通过相平衡计算,预测了它们在含水或不含水的溶剂体系中分配系数的变化趋势,并与前人的工作进行了对比。结果表明,由该方法预测出的相似结构溶质分配系数的顺序基本上与实验值相同,其中对饱和脂肪酸乙酯在己烷乙腈(体积比为1∶1)体系中分配系数的预测最好。这种预测方法的建立将对逆流色谱非电解质溶剂体系的选择具有较大的指导意义。

关键词：溶质出峰顺序预测逆流色谱通用基团活度系数分配系数 UNIFAC模型分离

The Existence and Stability of Nontrivial Steady-State for a Delay Competition-Diffusion Model

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Wuhan University Journal of Natural Sciences 1999年第4期4卷 377-381页

作者： ZHOU Li 1,SHAWGY Hussein 2 1.department of Mathematics, Huazhong University of Science and technology,Wuhan 43.074, china 2.department of Mathematics,Sudan University of Science and technology,Khartoum, Box 407, Sudan Huazhong University of Science and technology Department of Mathematics Wuhan China (GRID:grid.33199.31) (ISNI:***) Sudan University of Science and technology Department of Mathematics Khartoum Sudan (GRID:grid.440840.c)

This paper investigates the competition diffusion model with delay. The existence and stability of nontrivial steady state are studied.

关键词： Key words asymptotic expression steady state eigenvalue problem stability

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电阻网络电流分配的能量损耗最小原理

数学的实践与认识 2004年第1期34卷 7-12页

作者：夏登俊中国矿业大学物理系99级江苏徐州221008

首先提出了电阻网络电流分配的能量损耗最小原理 ,接着用此原理对一个电阻网络建立了二次规划数学模型 .求解此模型得到了各个支路上的电流值 .此电流值和由基尔霍夫定律计算出的电流值一致 ,同时由此原理推导出基尔霍夫电压定律 ,从而... 详细信息

首先提出了电阻网络电流分配的能量损耗最小原理 ,接着用此原理对一个电阻网络建立了二次规划数学模型 .求解此模型得到了各个支路上的电流值 .此电流值和由基尔霍夫定律计算出的电流值一致 ,同时由此原理推导出基尔霍夫电压定律 ,从而得出结论 :电阻网络电流分配的能量损耗最小原理是正确的 .最后 ,讨论了此原理在电路分析理论中的地位 .

关键词：电阻网络电流分配能量损耗最小原理基尔霍夫电压定律电路分析二次规划