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LOW TEMPERATURE THERMAL DEBINDING BEHAVIOR OF WAX-BASED MULTI-COMPONENT BINDER FOR TUNGSTEN HEAVY ALLOY 被引量:10
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作者 Fan, Jinglian Huang, Baiyun +1 位作者 Qu, Xuanhui Li, Yiming 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第1期95-100,共6页
1INTRODUCTIONPowderinjectionmoulding(PIM)isanewprocessformanufacturingnearnetshapepartswithadvantagesoflowco... 1INTRODUCTIONPowderinjectionmoulding(PIM)isanewprocessformanufacturingnearnetshapepartswithadvantagesoflowcost,highperformanc... 展开更多
关键词 THERMAL DEBINDING multi component BINDER TUNGSTEN HEAVY ALLOY
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Multi-component Dirac equation hierarchy and its multi-component integrable couplings system 被引量:8
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作者 夏铁成 尤福财 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第3期605-610,共6页
A general scheme for generating a multi-component integrable equation hierarchy is proposed. A simple 3M- dimensional loop algebra ~X is produced. By taking advantage of ~X a new isospectral problem is established and... A general scheme for generating a multi-component integrable equation hierarchy is proposed. A simple 3M- dimensional loop algebra ~X is produced. By taking advantage of ~X a new isospectral problem is established and then by making use of the Tu scheme the multi-component Dirac equation hierarchy is obtained. Finally, an expanding loop algebra ~FM of the loop algebra ~X is presented. Based on the ~FM, the multi-component integrable coupling system of the multi-component Dirac equation hierarchy is investigated. The method in this paper can be applied to other nonlinear evolution equation hierarchies. 展开更多
关键词 loop algebra zero curvature equation multi-component Dirac equation hierarchy multi-component integrable couplings system
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Multi-component AVO response of thin beds based on reflectance spectrum theory 被引量:7
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作者 Chen Tiansheng Liu Yang 《Applied Geophysics》 SCIE CSCD 2006年第1期27-36,共10页
地震 AVO 分析现在是为认出潜在的烃水库的主要标准之一。带 stratigraphic 结构,岩性学,和毛孔液体的信息的体积散布信息为地震探索是更有用的。然而,传统的 AVO 分析基于 Zoeppritz 方程,它仅仅包含单个接口的信息。薄床厚度的量... 地震 AVO 分析现在是为认出潜在的烃水库的主要标准之一。带 stratigraphic 结构,岩性学,和毛孔液体的信息的体积散布信息为地震探索是更有用的。然而,传统的 AVO 分析基于 Zoeppritz 方程,它仅仅包含单个接口的信息。薄床厚度的量的解释对薄床结构解释,水库描述,和侧面的水库预言必要。基于在频率的有弹性的波浪繁殖矩阵,域在这篇论文导出的反射光谱方程证明接口和间隔在振幅上有效果。方程关于单个接口并且体积散布包括信息。因为反射光谱方程是薄床厚度和频率的连续功能,在反射光谱上分析单个频率和床厚度的效果是方便的。床厚度是可被分析的直到床厚度是 vanishingly 小的。这些特征不能被 Fourier 变换完成。震波的繁殖是复杂的,各种各样的波浪模式同时存在。反射光谱包括各种各样的宣传波浪模式和 multiples 并且对模仿多部件更好薄床 AVO 回答比跟踪方法的光线。 展开更多
关键词 AVO 多分量 薄层 反射系数谱
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Layout problem of multi-component systems arising for improving maintainability 被引量:5
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作者 罗旭 杨拥民 +2 位作者 葛哲学 温熙森 官凤娇 《Journal of Central South University》 SCIE EI CAS 2014年第5期1833-1841,共9页
To improve the maintainability design efficiency and quality,a layout optimization method for maintainability of multi-component systems was proposed.The impact of the component layout design on system maintainability... To improve the maintainability design efficiency and quality,a layout optimization method for maintainability of multi-component systems was proposed.The impact of the component layout design on system maintainability was analyzed,and the layout problem for maintainability was presented.It was formulated as an optimization problem,where maintainability,layout space and distance requirement were formulated as objective functions.A multi-objective particle swarm optimization algorithm,in which the constrained-domination relationship and the update strategy of the global best were simply modified,was then used to obtain Pareto optimal solutions for the maintainability layout design problem.Finally,application in oxygen generation system of a spacecraft was studied in detail to illustrate the effectiveness and usefulness of the proposed method.The results show that the concurrent maintainability design can be carried out during the layout design process by solving the layout optimization problem for maintainability. 展开更多
关键词 可维护性 多组分体系 布局问题 PARETO最优解 粒子群优化算法 生成系统 维修性设计 设计效率
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Melt Index Prediction by Neural Soft-Sensor Based on Multi-Scale Analysis and Principal Component Analysis 被引量:11
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作者 施健 刘兴高 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期849-852,共4页
熔体流动指数( MI )的预言,在决定产品的最重要的参数“ s 等级和在实际工业进程生产的聚丙烯的质量管理, isstudied.A 小说有主要组分分析( PCA )的软传感器的模型,光线的基础函数( RBF )网络,并且多尺度的分析( MSA )被建议从真... 熔体流动指数( MI )的预言,在决定产品的最重要的参数“ s 等级和在实际工业进程生产的聚丙烯的质量管理, isstudied.A 小说有主要组分分析( PCA )的软传感器的模型,光线的基础函数( RBF )网络,并且多尺度的分析( MSA )被建议从真实进程变量推断生产产品的 MI ,在 PCA 被执行选择最相关的进程特征并且消除输入变量的关联的地方, MSA 被介绍获得更多信息并且减少系统的不确定性,并且 RBF 网络被用来描绘这进程的非线性。研究结果证明建议方法提供有希望的预言可靠性和精确性,并且想了在丙烯聚合过程有广泛的应用程序前景。 展开更多
关键词 多尺度分析 主元分析 聚丙烯 熔融指数 神经元软测量 预报模型
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Thermo-Calc based multi-component micro-segregation model and solidification paths calculations 被引量:3
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作者 Zhao Guangwei Li XinZhong +4 位作者 Xu Daming Guo Jingjie Fu Hengzhi Du Yong He Yuehui 《China Foundry》 SCIE CAS 2012年第3期269-274,共6页
On the basis of a multi-length scale modeling, a mixture-averaged multi-component /multiphase micro-segregation model was proposed without pre-set function for the micro-scale solute profile. The model explains the ef... On the basis of a multi-length scale modeling, a mixture-averaged multi-component /multiphase micro-segregation model was proposed without pre-set function for the micro-scale solute profile. The model explains the effect of morphologies of solidifying phases and solid back diffusion (SBD) on segregation, and covers the two limiting solidification cases of Scheil and Lever-rule models. A commercial Thermo-Calc software package/database was linked to the algorithms via its TQ6-interface for instantaneous determination of the related thermodynamic data of the multi-component alloys. The influences of cooling rate and other parameters on the solidification path and micro-segregation behavior were numerically investigated by sample calculation of the ternary Al-Cu-Mg alloys. A parallel experimental investigation on Al-Cu-Si alloys solidified under different cooling conditions was conducted to validate the theoretical model. Reasonable agreements were gained between the predicted solidification paths and the measured results. 展开更多
关键词 凝固路径 路径计算 THERMO-CALC软件 模型 显微偏析 多组分 热计算 微观尺度
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Generalized Multi-component TC Hierarchy and Its Multi-component Integrable Coupling System 被引量:1
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作者 XIA Tie-Cheng YOU Fu-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5X期793-798,共6页
A new 3M-dimensional Lie algebra X is constructed firstly. Then, the corresponding loop algebra X is produced, whose commutation operation defined by us is as simple and straightforward as that in the loop algebra A1.... A new 3M-dimensional Lie algebra X is constructed firstly. Then, the corresponding loop algebra X is produced, whose commutation operation defined by us is as simple and straightforward as that in the loop algebra A1.It follows that a generalscheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then well-known multi-component TC hierarchy is obtained. Finally,an expanding loop algebra FM of the loop algebra X is presented. Based on the FM, the multi-component integrable coupling system of the generalized multi-component TC hierarchy has been worked out. The method in this paper can be applied to other nonlinear evolution equations hierarchies. It is easy to find that we can construct any finite-dimensional Lie algebra by this approach. 展开更多
关键词 LIE代数 可积分耦合函数 环代数 TC层次
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Opportunistic maintenance for multi-component systems considering structural dependence and economic dependence 被引量:6
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作者 Junbao Geng Michael Azarian Michael Pecht 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期493-501,共9页
Although opportunistic maintenance strategies are widely used for multi-component systems, all opportunistic mainte- nance strategies only consider economic dependence and do not take structural dependence into accoun... Although opportunistic maintenance strategies are widely used for multi-component systems, all opportunistic mainte- nance strategies only consider economic dependence and do not take structural dependence into account. An opportunistic main- tenance strategy is presented for a multi-component system that considers both structural dependence and economic dependence. The cost relation and time relation among components based on structural dependence are developed. The maintenance strategy for each component of a multi-component system involves one of five maintenance actions, namely, no-maintenance, a minimal maintenance action, an imperfect maintenance action, a perfect maintenance action, and a replacement action. The maintenance action is determined by the virtual age of the component, the life expectancy of the component, and the age threshold values. Monte Carlo simulation is designed to obtain the optimal oppor- tunistic maintenance strategy of the system over its lifetime. The simulation result reveals that the minimum maintenance cost with a strategy that considers structural dependence is less than that with a strategy that does not consider structural dependence. The availability with a strategy that considers structural dependence is greater than that with a strategy that does not consider structural dependence under the same conditions. 展开更多
关键词 opportunistic maintenance multi-component system structural dependence Monte Carlo simulation maintenance cost.
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A novel synthesis of pyrazolo[3,4-b]pyridine derivatives through multi-component reaction in ionic liquid 被引量:3
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作者 Xin Ying Zhang Xiao Yan Li Xue Sen Fan Xia Wang Jian Ji Wang Gui Rong Qu 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期153-156,共4页
关键词 Pyrazolo[3 4-b]pyridine multi-component reaction Ionic liquid
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Multi-component synthesis of methylene bis isoxazolo[4,5-b]-pyridine-N-oxides 被引量:2
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作者 E.Rajanarendar M.Nagi Reddy K.Rama Murthy 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期927-930,共4页
A three component one-pot protocol was investigated for the synthesis of methylene bis isoxazolo[4,5-b]-pyridine-N-oxides from commercially available materials.
关键词 multi-component synthesis Knoevenagel condensation Michael addition New methodology
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Simulation of Multi-component Multi-stage Separation Process ——An Improved Algorithm and Application 被引量:1
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作者 李春山 张香平 +2 位作者 张锁江 谭心舜 项曙光 《过程工程学报》 EI CAS CSCD 北大核心 2006年第2期247-254,共8页
This paper presents a flexible model and a robust algorithm for simulation of multi-stage multi-component separation processes in which multiple feeds, side streams, strippers and/or side heat exchangers are involved.... This paper presents a flexible model and a robust algorithm for simulation of multi-stage multi-component separation processes in which multiple feeds, side streams, strippers and/or side heat exchangers are involved. The improved algorithm effectively accelerates the speed of convergence and offers better stability by introducing a damping factor for updating the stripping factor, and also reduces the requirement on the initial estimates by updating the Joacobian matrix directly with the stripping factor and enthalpy. On the other hand, an efficient algorithm was proposed to solve the approximate tri-diagonal matrix (containing the off-band elements) derived from the material balance equations (M equations) and phase equilibrium equations (E equations), the advantages and simplicity of the “insideout” technique of the Russell are retained. The present algorithm was demonstrated to be effective in simulating complex separation columns with typical case studies. 展开更多
关键词 分离 蒸馏 数值模拟 算法
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Data Mining-Based Maintenance Management Framework of Multi-component System 被引量:3
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作者 周瑜 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期950-953,共4页
Complex repairable system is composed of thousands of components.Some maintenance management and decision problems in maintenance management and decision need to classify a set of components into several classes based... Complex repairable system is composed of thousands of components.Some maintenance management and decision problems in maintenance management and decision need to classify a set of components into several classes based on data mining.Furthermore,with the complexity of industrial equipment increasing,the managers should pay more attention to the key components and carry out the lean management is very important.Therefore,the idea"customer segmentation"of"precise marketing"can be used in the maintenance management of the multi-component system.Following the idea of segmentation,the components of multicomponent systems should be subdivied into groups based on specific attributes relevant to maintenance,such as maintenance cost,mean time between failures,and failure frequency.For the target specific groups of parts,the optimal maintenance policy,health assessment and maintenance scheduling can be determined.The proposed analysis framework will be given out.In order to illustrate the effectiveness of this method,a numerical example is given out. 展开更多
关键词 maintenance management multi-component system data mining association rules CLUSTERING
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An Improved Adaptive Multi-way Principal Component Analysis for Monitoring Streptomycin Fermentation Process 被引量:8
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作者 何宁 王树青 谢磊 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第1期96-101,共6页
Multi-way principal component analysis (MPCA) had been successfully applied to monitoring the batch and semi-batch process in most chemical industry. An improved MPCA approach, step-by-step adaptive MPCA (SAMPCA), usi... Multi-way principal component analysis (MPCA) had been successfully applied to monitoring the batch and semi-batch process in most chemical industry. An improved MPCA approach, step-by-step adaptive MPCA (SAMPCA), using the process variable trajectories to monitoring the batch process is presented in this paper. It does not need to estimate or fill in the unknown part of the process variable trajectory deviation from the current time until the end. The approach is based on a MPCA method that processes the data in a sequential and adaptive manner. The adaptive rate is easily controlled through a forgetting factor that controls the weight of past data in a summation. This algorithm is used to evaluate the industrial streptomycin fermentation process data and is compared with the traditional MPCA. The results show that the method is more advantageous than MPCA, especially when monitoring multi-stage batch process where the latent vector structure can change at several points during the batch. 展开更多
关键词 链霉素 生产 发酵 多用途主成分分析
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SINGLE-DROP MASS TRANSFER COEFFICIENTS IN MULTICOMPONENT SYSTEMS 被引量:2
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作者 魏海国 费维扬 朱慎林 《化工学报》 EI CAS CSCD 北大核心 2002年第7期665-666,共2页
关键词 多组分体系 单液滴 传质系数 传质过程 化工过程
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Segregation modes,characteristics,and mechanisms of multi-component lignite in a vibrated gas-fluidized bed 被引量:1
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作者 Su Ding Luo Zhenfu +1 位作者 Lei Lingyan Zhao Yuemin 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第2期251-258,共8页
The segregation modes and characteristics of 1-6 mm multi-component lignite were studied in a microporous, vibrated, gas-fluidized bed of Φ110 mm ×400 mm. The effects of particle density and size, vibration freq... The segregation modes and characteristics of 1-6 mm multi-component lignite were studied in a microporous, vibrated, gas-fluidized bed of Φ110 mm ×400 mm. The effects of particle density and size, vibration frequency and amplitude, and gas velocity on these characteristics were considered. The average size, average density, size deviation coefficient, and density deviation coefficient were used to identify lignite size and density. The separation efficiency was adopted to evaluate the segregation performance,and the segregation mechanisms were explored. The results show that ε(size,max) of heterogeneous multisize-component lignite with K_(size) = 65% reaches 80% at f= 20 Hz, A = 5 mm, and N =(1,3). ε_(density,max) Of heterogeneous multi-density-component lignite with K_(density)= 25% reaches 50% at f = 15 Hz, A = 5 mm,and N =(1,1.5). The density segregations of 1-3 and 3-6 mm multi-component mixtures are remarkable,ε_(density,max)= 42% and 31% at f= 14 and 16 Hz, and A = 3 and 5 mm, respectively. The size segregation of 1-6 mm multi-component mixture is prominent and ε_(size,max)= 55% at f= 15 Hz, A = 5 mm. The mediumsized mixture with a narrow size distribution at low frequency is favorable for density segregation,and a mixture with a wider size distribution at high frequency is most favorable for size segregation.Precise control of gas flow and vibration as well as optimal design of the fluidized bed can improve the performance of segregation in the vibrated gas-fluidized bed. 展开更多
关键词 Dry-beneficiation multi-component LIGNITE SEGREGATION mode Degree of HOMOGENEITY
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Design of Drilling and Riveting Multi-functional End Effector for CFRP and Aluminum Components in Robotic Aircraft Assembly 被引量:6
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作者 Zhang Lin Tian Wei +4 位作者 Li Dawei Hong Peng Li Zhenyu Zhou Weixue Liao Wenhe 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第3期529-538,共10页
To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforc... To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforced polymer(CFRP)and aluminum components for a robotic aircraft assembly system.To meet the specific functional requirements for blind rivet installation on CFRP and aluminum materials,additional modules are incorporated on the end effector aside of the basic processing modules for drilling.And all of these processing modules allow for a onestep-drilling-countersinking process,hole inspection,automatic rivet feed,rivet geometry check,sealant application,rivet insertion and installation.Besides,to guarantee the better quality of the hole drilled and joints riveted,several online detection and adjustment measures are applied to this end effector,including the reference detection and perpendicular calibration,which could effectively ensure the positioning precision and perpendicular accuracy as demanded.Finally,the test result shows that this end effector is capable of producing each hole to a positioning precision within ±0.5 mm,aperpendicular accuracy within 0.3°,a diameter tolerance of H8,and a countersink depth tolerance of±0.01 mm.Moreover,it could drill and rivet up to three joints per minute,with acceptable shearing and tensile strength. 展开更多
关键词 robotic aircraft assembly CFRP and aluminum components automatic drilling and riveting multi-functional end effector online detection and adjustment
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A one-dimensional transport model for multi-component solute in saturated soil 被引量:1
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作者 Zhi-hong Zhang Jia-pei Zhang +1 位作者 Zhan-ying Ju Min Zhu 《Water Science and Engineering》 EI CAS CSCD 2018年第3期236-242,共7页
A modified multi-component solute diffusion equation described with diffusion flux was derived in detail based on the classical MaxwellStefan diffusion theory. The friction between the solute species and the soil skel... A modified multi-component solute diffusion equation described with diffusion flux was derived in detail based on the classical MaxwellStefan diffusion theory. The friction between the solute species and the soil skeleton wall, which is proportional to the relative velocity between the solute species and the soil skeleton, is introduced. The chemical potential gradient is considered the driving force. A one-dimensional model for transport of multi-component solute in saturated soil was developed based on the modified diffusion equation and the modified competitive Langmuir adsorption equation. Numerical calculation of a case of two heavy metal ion species, which was chosen as an example, was carried out using the finite element software COMSOL Multiphysics. A comparative analysis was performed between the multi-component solute transport model developed in this study and the convection-diffusion transport model of single-component solute based on Fick's law. Simulation results show that the transport behavior of each species in a multi-component solute system is different from that in a single-component system, and the friction characteristics considered in the developed model contribute to obstructing the movement of each solute component. At the same time,the influence of modified competitive Langmuir adsorption on solute transport was investigated. These research results can provide strong theoretical support for the design of antifouling barriers in landfills and the maintenance of operation stability. 展开更多
关键词 multi-component SOLUTE Maxwell-Stefan diffusion COMPETITIVE adsorption FRICTION Transport
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Similarity Reductions of(2+1)-Dimensional Multi-component Broer-Kaup System 被引量:1
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作者 DONG Zhong-Zhou CHEN Yong WANG Ling 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期803-808,共6页
Painlevé property of the (2+1)-dimensional multi-component Broer-Kaup (BK)system is considered byusing the standard Weiss-Kruskal approaches.Applying the Clarkson and Kruskal (CK) direct method to the (2+1)-dimen... Painlevé property of the (2+1)-dimensional multi-component Broer-Kaup (BK)system is considered byusing the standard Weiss-Kruskal approaches.Applying the Clarkson and Kruskal (CK) direct method to the (2+1)-dimensional multi-component BK system,some types of similarity reductions are obtained.By solving the reductions,one can get the solutions of the (2+1)-dimensional multi-component BK system. 展开更多
关键词 相似性归约 直接方法 多空间系统 数学
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A micropolar mixture theory of multi-component porous media 被引量:1
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作者 黄璐 赵成刚 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第5期617-630,共14页
A mixture theory is developed for multi-component micropolar porous media with a combination of the hybrid mixture theory and the micropolar continuum theory. The system is modeled as multi-component micropolar elasti... A mixture theory is developed for multi-component micropolar porous media with a combination of the hybrid mixture theory and the micropolar continuum theory. The system is modeled as multi-component micropolar elastic solids saturated with multi- component micropolar viscous fluids. Balance equations are given through the mixture theory. Constitutive equations are developed based on the second law of thermodynamics and constitutive assumptions. Taking account of compressibility of solid phases, the volume fraction of fluid as an independent state variable is introduced in the free energy function, and the dynamic compatibility condition is obtained to restrict the change of pressure difference on the solid-fluid interface. The constructed constitutive equations are used to close the field equations. The linear field equations are obtained using a linearization procedure, and the micropolar thermo-hydro-mechanical component transport model is established. This model can be applied to practical problems, such as contaminant, drug, and pesticide transport. When the proposed model is supposed to be porous media, and both fluid and solid are single-component, it will almost agree with Eringen's model. 展开更多
关键词 hybrid mixture theory MICROPOLAR multi-component deforming porous media
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Contact-impact formulation for multi-body systems using component mode synthesis 被引量:5
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作者 Peng Chen Jin-Yang Liu Jia-Zhen Hong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第3期437-442,共6页
The efficiency and accuracy are two most concerned issues in the modeling and simulation of multi-body systems involving contact and impact. This paper proposed a formulation based on the component mode synthesis meth... The efficiency and accuracy are two most concerned issues in the modeling and simulation of multi-body systems involving contact and impact. This paper proposed a formulation based on the component mode synthesis method for planar contact problems of flexible multi-body systems. A flexible body is divided into two parts: a contact zone and an un-contact zone. For the un-contact zone, by using the fixed-interface substructure method as reference, a few low-order modal coordinates are used to replace the nodal coordinates of the nodes, and meanwhile, the nodal coordinates of the local impact region are kept unchanged, therefore the total degrees of freedom (DOFs) are greatly cut down and the computational cost of the simulation is significantly reduced. By using additional constraint method, the impact constraint equations and kinematic constraint equations are derived, and the Lagrange equations of the first kind of flexible multi-body system are obtained. The impact of an elastic beam with a fixed half disk is simulated to verify the efficiency and accuracy of this method. 展开更多
关键词 Contact-impact analysis · Flexible multi-body system · component mode synthesis
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