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GLOBAL CONVERGENCE OF A CLASS OF OPTIMALLY CONDITIONED SSVM METHODS
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作者 杨正方 夏爱生 +1 位作者 韩立兴 刘光辉 《Transactions of Tianjin University》 EI CAS 1997年第1期73-76,共4页
This paper explores the convergence of a class of optimally conditioned self scaling variable metric (OCSSVM) methods for unconstrained optimization. We show that this class of methods with Wolfe line search are glob... This paper explores the convergence of a class of optimally conditioned self scaling variable metric (OCSSVM) methods for unconstrained optimization. We show that this class of methods with Wolfe line search are globally convergent for general convex functions. 展开更多
关键词 optimally conditioned self scaling variable metric methods global convergence unconstrained optimization
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A Fast Product of Conditional Reduction Method for System Failure Probability Sensitivity Evaluation 被引量:1
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作者 Jie Yang Changping Chen Ao Ma 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第12期1159-1171,共13页
Systemreliability sensitivity analysis becomes difficult due to involving the issues of the correlation between failure modes whether using analytic method or numerical simulation methods.A fast conditional reduction ... Systemreliability sensitivity analysis becomes difficult due to involving the issues of the correlation between failure modes whether using analytic method or numerical simulation methods.A fast conditional reduction method based on conditional probability theory is proposed to solve the sensitivity analysis based on the approximate analytic method.The relevant concepts are introduced to characterize the correlation between failure modes by the reliability index and correlation coefficient,and conditional normal fractile the for the multi-dimensional conditional failure analysis is proposed based on the two-dimensional normal distribution function.Thus the calculation of system failure probability can be represented as a summation of conditional probability terms,which is convenient to be computed by iterative solving sequentially.Further the system sensitivity solution is transformed into the derivation process of the failure probability correlation coefficient of each failure mode.Numerical examples results show that it is feasible to apply the idea of failure mode relevancy to failure probability sensitivity analysis,and it can avoid multi-dimension integral calculation and reduce complexity and difficulty.Compared with the product of conditional marginalmethod,a wider value range of correlation coefficient for reliability analysis is confirmed and an acceptable accuracy can be obtained with less computational cost. 展开更多
关键词 Probability of failure sensitivity approximate analytical method correlation coefficient conditional marginal method
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Theoretical aspects of selecting repeated unit cell model in micromechanical analysis using displacement-based finite element method 被引量:2
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作者 Lijun GAO Chengyu WANG +1 位作者 Zhanli LIU Zhuo ZHUANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第4期1417-1426,共10页
Repeated Unit Cell(RUC)is a useful tool in micromechanical analysis of composites using Displacement-based Finite Element(DFE)method,and merely applying Periodic Displacement Boundary Conditions(PDBCs)to RUC is ... Repeated Unit Cell(RUC)is a useful tool in micromechanical analysis of composites using Displacement-based Finite Element(DFE)method,and merely applying Periodic Displacement Boundary Conditions(PDBCs)to RUC is almost a standard practice to conduct such analysis.Two basic questions arising from this practice are whether Periodic Traction Boundary Conditions(PTBCs,also known as traction continuity conditions)are guaranteed and whether the solution is independent of selection of RUCs.This paper presents the theoretical aspects to tackle these questions,which unify the strong form,weak form and DFE method of the micromechanical problem together.Specifically,the solution’s independence of selection of RUCs is dealt with on the strong form side,PTBCs are derived from the weak form as natural boundary conditions,and the validity of merely applying PDBCs in micromechanical Finite Element(FE)analysis is proved by referring to its intrinsic connection to the strong form and weak form.Key points in the theoretical aspects are demonstrated by illustrative examples,and the merits of setting micromechanical FE analysis under the background of a clear theoretical framework are highlighted in the efficient selection of RUCs for Uni Directional(UD)fiber-reinforced composites. 展开更多
关键词 Finite element method Micromechanics of composites Periodic boundary condition Repeated unit cell Theoretical aspect Traction continuity
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From the new Austrian tunneling method to the geoengineering condition evaluation and dynamic controlling method 被引量:1
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作者 Yanjun Shang Kun Li +1 位作者 Wantong He Chunbo Sheng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第4期366-372,共7页
The new Austrian tunneling method (NATM) is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs) associated with the... The new Austrian tunneling method (NATM) is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs) associated with their influences on geoengineering are complicated or unfortunately are overlooked, we should pay more attentions to internal features of rocks grades IV and V (even in local but mostly controlling zones). With increasing attentions to the characteristics, mechanism and influences of engineering construction-triggered geohazards, it is crucial to fully understand the disturbance of these geohazards on project construction. A reasonable determination method in construction procedure, i.e. the shape of working face, the type of engineering support and the choice of feasible procedure, should be considered in order to mitigate the construction-triggered geohazards. Due to their high sensitivity to groundwater and in-situ stress, various UGBs exhibit hysteretic nature and failure modes. To give a complete understanding on the internal causes, the emphasis on advanced comprehensive geological forecasting and overall reinforcement treatment is therefore of more practical significance. Compre- hensive evaluation of influential factors, identification of UGB, and measures of discontinuity dynamic controlling comprises the geoengineering condition evaluation and dynamic controlling method. In a case of a cut slope, the variations of UGBs and the impacts of key environmental factors are presented, where more severe construction-triggered geohazards emerged in construction stage than those predicted in design and field investigation stages. As a result, the weight ratios of different influential factors with respect to field investigation, design and construction are obtained. 展开更多
关键词 Unfavorable geological body (UGB)Multi-factor interaction matrix Discontinuity dynamic controlling (DDC)Cut slope Geoengineering condition evaluation and dynamic controlling (GEDC) method
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ON THE METHOD OF ORTHOGONALITY CONDITIONS FOR SOLVING THE PROBLEM OF LARGE DEFLECTION OF CIRCULAR PLATE
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作者 戴世强 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第7期617-625,共9页
In this paper, we reexamine the method of successive approximation presented by Prof. Chien Wei-zangfor solving the problem of large deflection of a circular plate, and find that the method could be regarded as the me... In this paper, we reexamine the method of successive approximation presented by Prof. Chien Wei-zangfor solving the problem of large deflection of a circular plate, and find that the method could be regarded as the method of strained parameters in the singular perturbation theory. In terms of the parameter representing the ratio of the center deflection to the thickness of the plate, we make the asymptotic expansions of the deflection, membrane stress and the parameter of load as in Ref. [1], and then give the orthogonality conditions (i.e. the solvability conditions) for the resulting equations, by which the stiffness characteristics of the plate could be determined. It is pointed out that with the solutions for the small deflection problem of the circular plate and the orthogonality conditions, we can derive the third order approximate relations between the parameter of load and the center deflection and the first-term approximation of membrane stresses at the center and edge of the plate without solving the differential equations. For some special cases (i.e. under uniform load, under compound toad, with different boundary conditiors), we deduce the specific expressions and obtain the results in agreement with the previous ones given by Chien Wei-zang, Yeh kai-yuan and Hwang Chien in Refs. [1 - 4J. 展开更多
关键词 circular plate large deflection method of strained parameters orthogonality condition perturbation theory
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Herders'willingness to accept compensation for grassland grazing ban in Northwest China
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作者 Huifang Liu Lingling Hou +2 位作者 Zhibiao Nan Jikun Huang Liufang Su 《Journal of Integrative Agriculture》 2025年第1期366-379,共14页
Payment for Ecosystem Services(PES)has been widely acknowledged as an effective tool for mitigating grassland degradation and enhancing ecosystem services provision.However,critical factors,such as herders'willing... Payment for Ecosystem Services(PES)has been widely acknowledged as an effective tool for mitigating grassland degradation and enhancing ecosystem services provision.However,critical factors,such as herders'willingness to accept(WTA)preferences and compensation expectations,are often overlooked,leading to insufficient effectiveness of PES initiatives.This study focused on grassland ecological compensation policy(GECP),quantifying herders'WTA compensation for grassland grazing bans.Through face-to-face surveys and employing the contingent valuation method,we estimated households'WTA for participating in a grassland conservation program to bolster ecosystem service provision.Our findings indicated that herders required an average compensation of 237 CNY mu^(-1)yr^(-1)to engage in the grazing ban program.Notably,herders'environmental awareness positively influenced their willingness to participate,whereas larger family sizes were negatively correlated with WTA.Additionally,herders in better health,with higher livestock incomes or categorized as semi-herders,tended to accept lower compensation levels.These insights are crucial for improving the effectiveness of GECP and provide valuable reference points for similar analyses in economically disadvantaged and ecologically fragile regions. 展开更多
关键词 anchoring effect conditional value method double-bounded dichotomous choice model ecosystem services grassland system willingness to accept
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Analysis of the Conditional Correlations from Different Genetic Systems Between the Protein Content and the Appearance Quality Traits of Indica Rice 被引量:4
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作者 Guoke Ge Xi Zheng +2 位作者 Jianguo Wu Zihong Ye Chunhai Shi 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第2期129-137,共9页
A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines(A)and 5 restorer lines(R)along with their F1(A×R)and F2 populations.The unconditional and conditional analyses of... A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines(A)and 5 restorer lines(R)along with their F1(A×R)and F2 populations.The unconditional and conditional analyses of genetic models and the corresponding statistic methods,including endospermic,cytoplasmic,and maternal plant genetic systems,were used to analyze the genetic relationships between protein content(PC)and the appearance quality traits of indica rice(Oryza sativa L.).The results from unconditional analysis indicated that PC was significantly correlated with the appearance quality traits of rice,except for the brown rice thickness(BRT).Only the genetic covariance between PC and the brown rice width(BRW)was positively correlative,whereas all the other pairwise traits were negatively correlative.The results from conditional analysis revealed that the weight of brown rice(WBR)or the amylose content(AC)could significantly affect the relationships between PC and the appearance quality traits of indica rice.The conditional analysis showed that WBR might negatively affect the relationships between PC and the brown rice length(BRL),BRW,or BRT through the geuotype x environmental(GE)interaction effects,but positively affected the relationships between PC and the ratio of brown rice length to width(RLW)or the ratio of brown rice length to thickness(RLT).The amylase content could positively affect the relationships between PC and BRL,RLW,RLT through the cytoplasmic effects and maternal additive effects,but negatively affected the relationships between PC and BRW. 展开更多
关键词 indica rice(Oryza sativa L.) COVARIANCE unconditional and conditional analysis methods protein content amylose content appearance quality
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Designs to Improve Capability of Neural Networks to Make Structural Predictions 被引量:1
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作者 Tian-Yao Wang Jian-Feng Li +1 位作者 Hong-Dong Zhang Jeff Z.Y.Chen 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2023年第9期1477-1485,I0009,共10页
A deep neural network model generally consists of different modules that play essential roles in performing a task.The optimal design of a module for use in modeling a physical problem is directly related to the succe... A deep neural network model generally consists of different modules that play essential roles in performing a task.The optimal design of a module for use in modeling a physical problem is directly related to the success of the model.In this work,the effectiveness of a number of special modules,the self-attention mechanism for recognizing the importance of molecular sequence information in a polymer,as well as the big-stride representation and conditional random field for enhancing the network ability to produce desired local configurations,is numerically studied.Network models containing these modules are trained by using the well documented data of the native structures of the HP model and assessed according to their capability in making structural predictions of unseen data.The specific network design of self-attention mechanism adopted here is modified from a similar idea in natural language recognition.The big-stride representation module introduced in this work is shown to drastically improve network's capability to model polymer segments of strong lattice position correlations. 展开更多
关键词 Deep neural network Self-attention mechanism Big-stride representation Conditional random methods
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Prediction of plastic zone size around circular tunnels in non-hydrostatic stress field 被引量:7
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作者 Behnam Bagheri Fazlollah Soltani Hamid Mohammadi 《International Journal of Mining Science and Technology》 SCIE EI 2014年第1期81-85,共5页
This paper discusses the calculation of plastic zone properties around circular tunnels to rock-masses that satisfy the Hoek–Brown failure criterion in non-hydrostatic condition,and reviews the calculation of plastic... This paper discusses the calculation of plastic zone properties around circular tunnels to rock-masses that satisfy the Hoek–Brown failure criterion in non-hydrostatic condition,and reviews the calculation of plastic zone and displacement,and the basis of the convergence–confinement method in hydrostatic condition.A two-dimensional numerical simulation model was developed to gain understanding of the plastic zone shape.Plastic zone radius in any angles around the tunnel is analyzed and measured,using different values of overburden(four states)and stress ratio(nine states).Plastic zone radius equations were obtained from fitting curve to data which are dependent on the values of stress ratio,angle and plastic zone radius in hydrostatic condition.Finally validation of this equation indicate that results predict the real plastic zone radius appropriately. 展开更多
关键词 Plastic zone radius Convergence-confinement method Non-hydrostatic condition Stress ratio
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Energy-Efficient Transceiver Design for Multi-Pair Two-Way Relay Systems 被引量:3
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作者 Fei Zesong Li Na +1 位作者 Xing Chengwen Gong Shiqi 《China Communications》 SCIE CSCD 2015年第9期133-140,共8页
In this paper, we focus on energy-efficient transceiver and relay beamforming design for multi-pair two-way relay system. The multi-antenna users and the multi-antenna relay are considered in this work. Different from... In this paper, we focus on energy-efficient transceiver and relay beamforming design for multi-pair two-way relay system. The multi-antenna users and the multi-antenna relay are considered in this work. Different from the existing works, the proposed algorithm is energy-efficient which is more applicable to the future green network. It considers both the sum-MSE problem and the power consumption problem for the users under the relay power constraint. Based on the optimal condition decomposition(OCD) method, the energy-efficient precoders at the users can be designed separately with limited information exchanged. The proposed relay beamforming algorithm is based on the alternative direction method of multipliers(ADMM) which has simpler iterative solution and enjoys good convergence. Simulation results demonstrate the performance of the proposed algorithms in terms of power consumption and MSE performance. 展开更多
关键词 two-way relay energy efficient optimal condition decomposition alternative direction method of multipliers
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A fast and automatic full-potential finite volume solver on Cartesian grids for unconventional configurations 被引量:5
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作者 Fanxi LYU Tianhang XIAO Xiongqing YU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第3期951-963,共13页
To meet the requirements of fast and automatic computation of subsonic and transonic aerodynamics in aircraft conceptual design,a novel finite volume solver for full potential flows on adaptive Cartesian grids is deve... To meet the requirements of fast and automatic computation of subsonic and transonic aerodynamics in aircraft conceptual design,a novel finite volume solver for full potential flows on adaptive Cartesian grids is developed in this paper.Cartesian grids with geometric adaptation are firstly generated automatically with boundary cells processed by cell-cutting and cell-merging algorithms.The nonlinear full potential equation is discretized by a finite volume scheme on these Cartesian grids and iteratively solved in an implicit fashion with a generalized minimum residual(GMRES) algorithm.During computation,solution-based mesh adaptation is also applied so as to capture flow features more accurately.An improved ghost-cell method is proposed to implement the non-penetration wall boundary condition where the velocity-potential of a ghost cell is modified by an analytic method instead.According to the characteristics of the Cartesian grids,the Kutta condition is applied by specially computing the gradients on Kutta-faces without directly assigning the potential jump to cells adjacent wake faces,which can significantly improve the solution converging speed.The feasibility and accuracy of the proposed method are validated by several typical cases of sub/transonic flows around an ONERA M6 wing,a DLR-F4 wing-body,and an unconventional figuration of a blended wing body(BWB).The validation cases demonstrate a fast convergence with fully automatic grid treatment and computation,and the results suggest its capacity in application for aircraft conceptual design. 展开更多
关键词 Cartesian grids CUT-cell Finite volume method Full potential equation Grid adaptation Kutta condition Non-penetration condition
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The constructive technique and its application in solving a nonlinear reaction diffusion equation
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作者 赖绍永 郭云喜 +1 位作者 青音 吴永宏 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第2期405-410,共6页
A mathematical technique based on the consideration of a nonlinear partial differential equation together with an additional condition in the form of an ordinary differential equation is employed to study a nonlinear ... A mathematical technique based on the consideration of a nonlinear partial differential equation together with an additional condition in the form of an ordinary differential equation is employed to study a nonlinear reaction diffusion equation which describes a real process in physics and in chemistry. Several exact solutions for the equation are acquired under certain circumstances. 展开更多
关键词 additional generating condition method exact solutions nonlinear reaction-diffusion equation
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Axisymmetric Powell-Eyring fluid flow with convective boundary condition: optimal analysis 被引量:1
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作者 T.HAYAT S.MAKHDOOM +2 位作者 M.AWAIS S.SALEEM M.M.RASHIDI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第7期919-928,共10页
The effects of axisymmetric flow of a Powell-Eyring fluid over an impermeable radially stretching surface are presented. Characteristics of the heat transfer process are analyzed with a more realistic condition named ... The effects of axisymmetric flow of a Powell-Eyring fluid over an impermeable radially stretching surface are presented. Characteristics of the heat transfer process are analyzed with a more realistic condition named the convective boundary condition. Governing equations for the flow problem are derived by the boundary layer approximations. The modeled highly coupled partial differential system is converted into a system of ordinary differential equations with acceptable similarity transformations. The convergent series solutions for the resulting system are constructed and analyzed. Optimal values are obtained and presented in a numerical form using an optimal homotopy analysis method (OHAM). The rheological characteristics of different parameters of the velocity and temperature profiles are presented graphically. Tabular variations of the skin friction coefficient and the Nusselt number are also calculated. It is observed that the temperature distribution shows opposite behavior for Prandtl and Biot numbers. Furthermore, the rate of heating/cooling is higher for both the Prandtl and Biot numbers. 展开更多
关键词 axisymmetric flow optimal homotopy analysis method (OHAM) analysis convective boundary condition
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New Exact Solutions and Evolution of Solitons in Background Waves for(2+1)-Dimensional Modified Dispersive Water-Wave System
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作者 MA Song-Hua JIANG Yong-Qing FANG Jian-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期938-942,共5页
With the help of the conditional similarity reduction method, some new exact solutions of the (2+1)- dimensional modified dispersive water-wave system (MDWW) are obtained. Based on the derived solution, we invest... With the help of the conditional similarity reduction method, some new exact solutions of the (2+1)- dimensional modified dispersive water-wave system (MDWW) are obtained. Based on the derived solution, we investigate the evolution of solitons in the background waves. 展开更多
关键词 conditional similarity reduction method modified dispersive water-wave system exact solutions EVOLUTION background waves
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Statistical second-order two-scale analysis and computation for heat conduction problem with radiation boundary condition in porous materials
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作者 杨志强 刘世伟 孙毅 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期189-197,共9页
This paper discusses a statistical second-order two-scale(SSOTS) analysis and computation for a heat conduction problem with a radiation boundary condition in random porous materials.Firstly,the microscopic configur... This paper discusses a statistical second-order two-scale(SSOTS) analysis and computation for a heat conduction problem with a radiation boundary condition in random porous materials.Firstly,the microscopic configuration for the structure with random distribution is briefly characterized.Secondly,the SSOTS formulae for computing the heat transfer problem are derived successively by means of the construction way for each cell.Then,the statistical prediction algorithm based on the proposed two-scale model is described in detail.Finally,some numerical experiments are proposed,which show that the SSOTS method developed in this paper is effective for predicting the heat transfer performance of porous materials and demonstrating its significant applications in actual engineering computation. 展开更多
关键词 statistical second-order two-scale method radiation boundary condition random porous materials
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Evaluate the Value of Houses around the Garbage Transfer Station Based on CVM
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作者 Zihan Yang 《Journal of Sustainable Business and Economics》 2024年第3期1-14,共14页
In recent years,with the rapid development of China’s economy,a large number of people have flocked to the cities,which also brings more residential waste.The increased waste overloads transfer stations located near ... In recent years,with the rapid development of China’s economy,a large number of people have flocked to the cities,which also brings more residential waste.The increased waste overloads transfer stations located near residential areas,and the continuous noise and odour affect the daily lives of nearby residents.In addition,the neighbourhood avoidance facilities represented by the waste transfer stations also reduce the value of the surrounding residents’houses.Therefore,using the conditional value method and the Tobit and Double Hurder econometric models,this article investigates the implicit value of the Fuli Resort neighbourhood under the influence of the waste transfer station through a questionnaire survey on the willingness of the residents to accept the compensation,which can be regarded as the“aversion value”of the neighbourhood due to the aversion to the waste transfer station and analyses the impact of the aversion value of the neighbourhood.aversion value and analyses the impact on residents’willingness to accept compensation.The study found that the residents’willingness to accept compensation near the waste transfer station is 511.94 RMB/person/month,and the implicit value of the Fuli Resort neighbourhood under the influence of the waste transfer station in Qinhuai District,Nanjing,Jiangsu Province,China,is 147,950 RMB.The study found that residents are most interested in having the government rectify the waste transfer station and set sanitary standards and work norms. 展开更多
关键词 Refuse transfer station House price Invisible price Conditional value method Willingness to be compensated
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THE EXACT SOLUTIONS OF ELASTIC-PLASTIC CRACK LINE FIELD FOR MODE Ⅱ PLANE STRESS CRACK
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作者 易志坚 王士杰 王向坚 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第10期977-984,共8页
The near crack line field analysis method has been used io investigate into theexact elastic-plastic solutions of a mode II crack under plane stress condilion in anelastic-perfectly plastic solid. The assumptions of t... The near crack line field analysis method has been used io investigate into theexact elastic-plastic solutions of a mode II crack under plane stress condilion in anelastic-perfectly plastic solid. The assumptions of the usual small scale yielding theory.hare been completely. dbandoned and the correct formulations of matching conditionsat the elaslic-plastic boundary. have been given. By, matching the general solution ofthe plastic slress field (bul not the special solution used to be adopted) with the exactelastic stress field (but not the crack tip K-dominant field) at the elastic-plasticboundary, near the crack line, the plastic stresses. the length of the plastic =one and theunit normal vector of the elastic-plastic boundary.which are sufficiently precise near the crack line region ,have been given. 展开更多
关键词 mode II crack. near crack line analysis method. crack line. elastic-plastic boundary. matching conditions
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THE EXACT SOLUTIONS OF ELASTIC-PLASTIC CRACK LINE FIELD FOR MODE Ⅱ PLANE STRESS CRACK
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作者 易志坚 王士杰 王向坚 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第5期977-984,共8页
The near crack line field analysis method has been used to investigate into the exact elastic-plastic solutions of a mode Ⅱ crack under plane stress condition in anelastic-perfectly plastic solid. The assumptions of ... The near crack line field analysis method has been used to investigate into the exact elastic-plastic solutions of a mode Ⅱ crack under plane stress condition in anelastic-perfectly plastic solid. The assumptions of the usual small scale yielding theoryhave been completely. dbandoned and the correct .formulations of matching conditionsat the elastic-plastic boundary have been given. By matching the general solution of the plastic stress field (but not the special solution used to be adopted) will the exactelastic stress field (but not the crack tip K-dominant field) at the elastic-plasticboundary. near the crack line, the plastic .stresses, the length of the plastic zone and theunit normal vector of the elaslic-plastic boundary. which sufficiently precise nearthe crack line region, hare been given. 展开更多
关键词 mode Ⅱcrack. near crack line analysis method. crack line. elastic-plastic boundary. matching conditions
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UBM STUDY ON DOUBLE-DIE IRONING PROCESS
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作者 Wang Liansheng Dong Liang Dong Shisheng Taiyuan Heavy Machinery InstituteHan Jingtao Qinghua University 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1994年第3期225-231,236,共17页
The double-die ironing process is studied by means of UBM. The formulas of deformation load.contact stress on die surface, and tensile stress which acts on workpiece is obtained. Taking account of dirnensional accurac... The double-die ironing process is studied by means of UBM. The formulas of deformation load.contact stress on die surface, and tensile stress which acts on workpiece is obtained. Taking account of dirnensional accuracy, a new critical condition of limit reduction in cross section area is put forward for the flrst time. The test experiment indicats that results of theoretical analysis well accord with the actual conditions.[0] 展开更多
关键词 Upper boundary method Double-die ironing Forming limit Critical condition of limit strain
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The Transformation of China'sEconomic Growth Pattern─Conditions and Methods 被引量:1
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作者 郭克莎 《Social Sciences in China》 1997年第3期12-20,191,共10页
关键词 The Transformation of China’sEconomic Growth Pattern Conditions and methods
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