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Catastrophe Theory Models for Stress-dependent Behaviour in a NiTi Shape Memory Alloy
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作者 Bruce Friedman(Sunrise Enterprises, 1023 Hanson Street, Annapolis, Maryland 21403, USA) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1994年第1期31-33,共3页
The measurements by Huibin XU et al of the stress-dependence ot hysteresis in a NiTi shape memo ry alloy are modeled by catastrophe theory. The cusp catastrophe is used with the strain as the behaviour variable and t... The measurements by Huibin XU et al of the stress-dependence ot hysteresis in a NiTi shape memo ry alloy are modeled by catastrophe theory. The cusp catastrophe is used with the strain as the behaviour variable and the control parameters being functions of the stress and the temperature. A two constant model is found to be preferred to a four constant model. 展开更多
关键词 NITI Catastrophe theory models for Stress-dependent Behaviour in a NiTi Shape Memory Alloy
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Research status of soil frost-heave theory and frost-heave prediction models
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作者 XiangDong Zhang ShengYang Feng 《Research in Cold and Arid Regions》 2010年第1期82-86,共5页
Soil frost heaving is a complex physical, mechanical, and chemical synthesis process. This paper summarizes the frost-heaving theory over half a century, including the capillary theory, the frozen-fringe theory, and t... Soil frost heaving is a complex physical, mechanical, and chemical synthesis process. This paper summarizes the frost-heaving theory over half a century, including the capillary theory, the frozen-fringe theory, and those achievements recently made by scholars. In this paper, we also discus researching achievements of the soil-prediction model during the past 40 years, including the water-dynamics model, the rigid-ice model, the segregation-potential model, and the thermo-dynamic model. This summary and discussion will enable readers to understand the latest direction of research; it also summarizes the development of frost-heave prediction models and their advantages and shortcomings. 展开更多
关键词 frost heaving theory frost heaving model research status
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On capped Higgs positivity cone
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作者 Dong-Yu Hong Zhuo-Hui Wang Shuang-Yong Zhou 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第7期44-54,43,I0003,共13页
The Wilson coefficients of the standard model effective field theory are subject to a series of positivity bounds.It has been shown that while the positivity part of the ultraviolet(UV)partial wave unitarity leads to ... The Wilson coefficients of the standard model effective field theory are subject to a series of positivity bounds.It has been shown that while the positivity part of the ultraviolet(UV)partial wave unitarity leads to the Wilson coefficients living in a convex cone,further including the nonpositivity part caps the cone from above.For Higgs scattering,a capped positivity cone was obtained using a simplified,linear unitarity condition without utilizing the full internal symmetries of Higgs scattering.Here,we further implement stronger nonlinear unitarity conditions from the UV,which generically gives rise to better bounds.We show that,for the Higgs case in particular,while the nonlinear unitarity conditions per se do not enhance the bounds,the fuller use of the internal symmetries do shrink the capped positivity cone significantly. 展开更多
关键词 positivity bounds standard model effective field theory(SMEFT) HIGGS
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Understanding factors affecting non-participants’interest in community-supported agriculture
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作者 Maula Fadhilata RAHMATIKA Agus SUMAN +1 位作者 Wildan SYAFITRI Sri MULJANINGSIH 《Regional Sustainability》 2024年第3期69-80,共12页
Community-supported agriculture(CSA)has emerged as a viable solution for addressing the agricultural challenges faced by countries like Indonesia.This study uses the wellestablished unified theory of acceptance and us... Community-supported agriculture(CSA)has emerged as a viable solution for addressing the agricultural challenges faced by countries like Indonesia.This study uses the wellestablished unified theory of acceptance and use of technology(UTAUT2)model to examine the interest in CSA of potential customers in Indonesia.A standardized questionnaire was distributed to 1200 respondents,and the data were analyzed using structural equation model-partial least square(SEM-PLS)in SmartPLS 4.0 software.The results capture potential CSA consumer interest and will help to improve CSA development strategies in Indonesia.The model explains 44.4%of customers’intentions,and identifies performance expectancy as the decisive factor in customers’willingness to participate in CSA.Performance expectancy(0.292),hedonic motivation(0.262),social influence(0.259),and facilitating conditions(0.086)positively influence customers’interest in participating in a CSA program.The adoption of CSA programs by both farmers and customers could be increased by implementing regulations that provide tax incentives and subsidies,offering training on sustainable farming practices,facilitating the establishment of distribution channels,and establishing guidelines for fair price and quality standards.This study shows the high potential for the implementation of CSA in Indonesia.It could also be used as a foundation for the development of new policies regarding sustainable agriculture markets in Indonesia. 展开更多
关键词 Community-supported agriculture(CSA) Sustainable agriculture Behavioral intention Performance expectancy Unified theory of acceptance and use of technology model Indonesia
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Dynamic subsidence basins in coal mines based on rock mass rheological theory 被引量:4
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作者 Yang Yu Gong Zhiqiang Liang Bing 《Mining Science and Technology》 EI CAS 2011年第3期333-335,共3页
In order to investigate the surface deformation caused by coal mining and to reduce environmental damage, more accurate information of dynamic subsidence basins, caused by coal mining, is needed. Based on theological ... In order to investigate the surface deformation caused by coal mining and to reduce environmental damage, more accurate information of dynamic subsidence basins, caused by coal mining, is needed. Based on theological theory, we discuss surface deformation mechanism of dynamic subsidence on the assumption that both the roof and the coal seam are visco-elastic media, put forward the idea that the principle of surface deformation is similar to that of roofs, except for their parameters. Therefore, a surface deforma- tion equation can be obtained, given the equation of the roof deformation derived.from using a HIM rhe- ological model. In the end, we apply the equation of surface deformation as a practical subsidence prediction in a coal mine. Given the theologic properties of a rock mass, the results of our research of a dynamic subsidence basin can predict the development of surface deformation as a function of time, which is more important than the ultimate subsidence itself. The results indicate that using rheological theory to calculate the deformation of a dynamic subsidence basin is suitable and provides some reference for surface deformation of dynamic subsidence basins. 展开更多
关键词 Coal mining subsidenceDynamic basinRheological theorie sHiM theological model
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MULTI-FLEXIBLE SYSTEM DYNAMIC MODELING THEORY AND APPLICATION 被引量:1
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作者 仲昕 周兵 杨汝清 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第2期197-200,共4页
The flexible body modeling theory was demonstrated. An example of modeling a kind of automobile’s front suspension as a multi-flexible system was shown. Finally, it shows that the simulation results of multi-flexible... The flexible body modeling theory was demonstrated. An example of modeling a kind of automobile’s front suspension as a multi-flexible system was shown. Finally, it shows that the simulation results of multi-flexible dynamic model more approach the road test data than those of multi-rigid dynamic model do. Thus, it is fully testified that using multi-flexible body theory to model is necessary and effective. 展开更多
关键词 multi-flexible body flexible body modeling theory automobile’s front suspension
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AXIAL HEAT CONDUCTION MODEL TO PREDICT MAXIMUM HEAT REMOVE OF MINIATURE HEAT PIPE BASED ON GREY MODEL THEORY 被引量:3
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作者 Tsai Mengchang Chang Shinhsing Kang Shungwen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期477-481,共5页
Computer chip is always accompanied by the increase of heat dissipation and miniaturization. The miniature heat pipes are widely used in notebook computer to resolve the heat dissipation problems. Maximum heat removed... Computer chip is always accompanied by the increase of heat dissipation and miniaturization. The miniature heat pipes are widely used in notebook computer to resolve the heat dissipation problems. Maximum heat removed model of miniature heat pipes building by grey model is presented. In order to know the foundation for modeling, the smooth grade of error examination is inquired and the accuracy of grey relational grade is verified. The model can be used to select a suitable heat pipes to solve electric heat problems in the future. Final results show that the grey model only needs four experiment data and its error value is less than 10%, further, it is better than computational fluid dynamics (CFD) model. 展开更多
关键词 Maximum heat removed model Miniature heat pipe Grey model theory Computational fluid dynamics (CFD) Grey relational grade
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Numerical verification of similar Cam-clay model based on generalized potential theory 被引量:2
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作者 钟志辉 杨光华 +2 位作者 傅旭东 温勇 张玉成 《Journal of Central South University》 SCIE EI CAS 2014年第12期4707-4713,共7页
From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential ... From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential theory, has less assumptions,clearer mathematical basis, and better computational accuracy. Theoretically, it is more scientific than the traditional Cam-clay models. The particle flow code PFC3 D was used to make numerical tests to verify the rationality and practicality of the similar Cam-clay model. The verification process was as follows: 1) creating the soil sample for numerical test in PFC3 D, and then simulating the conventional triaxial compression test, isotropic compression test, and isotropic unloading test by PFC3D; 2)determining the parameters of the similar Cam-clay model from the results of above tests; 3) predicting the sample's behavior in triaxial tests under different stress paths by the similar Cam-clay model, and comparing the predicting results with predictions by the Cam-clay model and the modified Cam-clay model. The analysis results show that the similar Cam-clay model has relatively high prediction accuracy, as well as good practical value. 展开更多
关键词 generalized potential theory similar Cam-clay model modified Cam-clay model numerical test PFC3D
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Self-Organized Criticality Theory Model of Thermal Sandpile 被引量:1
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作者 彭晓东 曲洪鹏 +1 位作者 许健强 韩最蛟 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期79-83,共5页
A self-organized criticality model of a thermal sandpile is formulated for the first time to simulate the dynamic process with interaction between avalanche events on the fast time scale and diffusive transports on th... A self-organized criticality model of a thermal sandpile is formulated for the first time to simulate the dynamic process with interaction between avalanche events on the fast time scale and diffusive transports on the slow time scale. The main characteristics of the model are that both particle and energy avalanches of sand grains are considered simultaneously. Properties of intermittent transport and improved confinement are analyzed in detail. The results imply that the intermittent phenomenon such as blobs in the low confinement mode as well as edge localized modes in the high confinement mode observed in tokamak experiments are not only determined by the edge plasma physics, but also affected by the core plasma dynamics. 展开更多
关键词 Self-Organized Criticality theory Model of Thermal Sandpile
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The Study of Chamber Rockburst by the CUSP Model of Catastrophe Theory 被引量:4
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作者 潘一山 章梦涛 李国臻 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第10期943-951,共9页
By means of CUSP model of catastrophe theory. this paper has studied thephysics process of rockburst occured on circular chamber. The present paper has nolonly described the instability process of rockburst more deepl... By means of CUSP model of catastrophe theory. this paper has studied thephysics process of rockburst occured on circular chamber. The present paper has nolonly described the instability process of rockburst more deeply. but also got the crilicaldepth of plastic softening area of chamber that is valuable in the controlling engineering of rockburst. the chamber displacement jump and energy liberation have been derived. the influence of rock parameters on the rockburst has been discussed . 展开更多
关键词 rockburst. CUSP model of catastrophe theory. critical depth ofplastic softening area. displacement jump. energy liberation
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THE COUPLING DYNAMICAL MODELING THEORY OF FLEXIBLE MULTIBODY SYSTEM
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作者 Jiang, LZ Hong, JZ 《Acta Mechanica Solida Sinica》 SCIE EI 1999年第4期365-372,共8页
Based on the deformation theory of elastic beams, the coupling effect between the coupling displacements of a point on the middle line of beam and large overall motion is presented. The 'coupling matrix library... Based on the deformation theory of elastic beams, the coupling effect between the coupling displacements of a point on the middle line of beam and large overall motion is presented. The 'coupling matrix library' and Jourdain's variation principle and single direction recursive formulation method are used to establish the general coupling dynamical equations of flexible multibody system. Two typical examples show the coupling effect between coupling displacements and large overall motion on the dynamics of flexible multibody system consisting of beams. 展开更多
关键词 coupling displacement coupling dynamical modeling theory large overall motion single direction recursive formulation flexible multibody system
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ON THE CLOSURE PROBLEM OF TURBULENCE MODEL THEORY
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作者 蔡树棠 刘宇陆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第3期225-227,共3页
It is a wrong viewpoint that the turbulence closure problem is due to thenon-linearity, of N-S equation, because if we omit the non-linear terms in N-Sequation,many, physical quantities can not be obtained other than... It is a wrong viewpoint that the turbulence closure problem is due to thenon-linearity, of N-S equation, because if we omit the non-linear terms in N-Sequation,many, physical quantities can not be obtained other than the mean-values. Inthis paper, we proof that the closure problem of turbulence be induced by lack ofstatistical disiribution in present turbulence theory. And the restriction of turbulencemodel theory and shortcoming of direct numerical simulation of N-S to solve theturbulence have been pointed out. 展开更多
关键词 turbulence. closure problem. model theory distribution function
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A Novel Formal Theory for Security Protocol Analysis of Denial of Service Based on Extended Strand Space Model
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作者 JIANG Rui 《China Communications》 SCIE CSCD 2010年第4期23-28,共6页
Denial of Service Distributed Denial of Service (DOS) attack, especially (DDoS) attack, is one of the greatest threats to Internet. Much research has been done for it by now, however, it is always concentrated in ... Denial of Service Distributed Denial of Service (DOS) attack, especially (DDoS) attack, is one of the greatest threats to Internet. Much research has been done for it by now, however, it is always concentrated in the behaviors of the network and can not deal with the problem exactly. In this paper, we start from the security of the protocol, then we propose a novel theory for security protocol analysis of Denial of Service in order to deal with the DoS attack. We first introduce the conception of weighted graph to extend the strand space model, then we extend the penetrator model and define the goal of anti-DoS attack through the conception of the DoS-stop protocol, finally we propose two kinds of DoS test model and erect the novel formal theory for security protocol analysis of Denial of Service. Our new formal theory is applied in two example protocols. It is proved that the Internet key exchange (IKE) easily suffers from the DoS attacks, and the efficient DoS- resistant secure key exchange protocol (JFK) is resistant against DoS attack for the server, respectively. 展开更多
关键词 Denial of Service Security Protocol Analysis Formal theory Strand Space Model Internet Key Exchange
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A New Solution with Torsion in Model of dS Gauge Theory of Gravity
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作者 黄超光 马孟森 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第1期65-68,共4页
A new static de Sitter solution with torsion in the model of de Sitter gauge theory of gravity is obtained. The torsion only contains Q(3)-symmetric tensor part according to irreducible decomposition. Some propertie... A new static de Sitter solution with torsion in the model of de Sitter gauge theory of gravity is obtained. The torsion only contains Q(3)-symmetric tensor part according to irreducible decomposition. Some properties of the new solution are discussed. 展开更多
关键词 static dS solution with torsion model dS gauge theory of gravity tensor part of torsion
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Research on Regulating and Controlling Homogenization of Entertainment Programs--Based on Game Theory
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作者 Chen Mei Tian Shuge 《International English Education Research》 2014年第12期17-20,共4页
With the prevailing and popular entertainment programs, it brought huge benefits to TV stations, but at the same time caused a variety problems of homogenization. The paper analyzes the causes of the entertainment pro... With the prevailing and popular entertainment programs, it brought huge benefits to TV stations, but at the same time caused a variety problems of homogenization. The paper analyzes the causes of the entertainment programs, the root of homogenization, building game theory models between TV stations, TV station and audience to regulate and control the issue of homogeneity about entertainment programs. 展开更多
关键词 Entertainment Programs HOMOGENIZATION Game theory Model Regulate and Control.
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Granularity of Knowledge Computed by Genetic Algorithms Based on Rough Sets Theory
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作者 Wenyuan Yang Xiaoping Ye +1 位作者 Yong Tang Pingping Wei 《南昌工程学院学报》 CAS 2006年第2期97-101,121,共6页
Rough set philosophy hinges on the granularity of data, which is used to build all its basic concepts, like approximations, dependencies, reduction etc. Genetic Algorithms provides a general frame to optimize problem ... Rough set philosophy hinges on the granularity of data, which is used to build all its basic concepts, like approximations, dependencies, reduction etc. Genetic Algorithms provides a general frame to optimize problem solution of complex system without depending on the domain of problem.It is robust to many kinds of problems.The paper combines Genetic Algorithms and rough sets theory to compute granular of knowledge through an example of information table. The combination enable us to compute granular of knowledge effectively.It is also useful for computer auto-computing and information processing. 展开更多
关键词 granularity of knowledge Genetic Algorithms Pawlak Model Rough Set theory information table
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Cold Nuclear Fusion in the Unitary Quantum Theory
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作者 Lev G.Sapogin Igor V.Kulikov 《Chinese journal of nuclear physics》 1995年第4期360-370,共11页
The interaction of the charged particles in the new Unitary Quantum theory isconsidered. It is shown that the distance of approachment of deuterons to each other verystrongly depends on the phase of the wave function ... The interaction of the charged particles in the new Unitary Quantum theory isconsidered. It is shown that the distance of approachment of deuterons to each other verystrongly depends on the phase of the wave function and not only upon the energy. This thesis isnot discussed in the conventional quantum theory. It can easily explain the experiments on thecold nuclear fusion. 展开更多
关键词 Cold nuclear fusion Unitary quantum theory Non-linear or nonlocal theories and models Nuclear reaction and scattering models
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Application of fuzzy optimization model in the evaluationof urban flood-waterloggedvulnerabilitybased on the synthetic weight ofgame theory
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作者 LIU Ke 《International Journal of Technology Management》 2014年第5期6-9,共4页
The evaluation of urban flood-waterlogged vulnerability is very important to the safety of urban flood control. In this paper, the evaluation of consolidated index is used. Respectively, AHP and entropy method calcula... The evaluation of urban flood-waterlogged vulnerability is very important to the safety of urban flood control. In this paper, the evaluation of consolidated index is used. Respectively, AHP and entropy method calculate the subjective and objective weight of the evaluation indicators, and combine them by game theory. So we can obtain synthetic weight based on objective and subjective weights. The evaluation of urban flood-waterlogged vulnerability as target layer, a single variable multi-objective fuzzy optimization model is established. We use the model to evaluate flood-waterlogged vulnerability of 13 prefecture-level city in Hunan, and compare it with other evaluation method. The results show that the evaluation method has certain adaptability and reliability, and it' s helpfid to the construction planning of urban flood control. 展开更多
关键词 Evaluation of urban flood-waterlogged vulnerability Synthetic weights Game theory Variable fuzzy optimization model
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Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models
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作者 Qiang Wang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第4期532-543,共12页
Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and s... Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N. 展开更多
关键词 Generic polymer models Soft potentials Polymer reference interaction site model theory
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Research and Development Trend of Shape Control for Cold Rolling Strip 被引量:22
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作者 Dong-Cheng Wang Hong-Min Liu Jun Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第5期1248-1261,共14页
Shape is an important quality index of cold rolling strip. Up to now, many problems in the shape control domain have not been solved satisfactorily, and a review on the research progress in the shape control domain ca... Shape is an important quality index of cold rolling strip. Up to now, many problems in the shape control domain have not been solved satisfactorily, and a review on the research progress in the shape control domain can help to seek new breakthrough directions. In the past 10 years, researches and applications of shape control models, shape control means, shape detection technology, and shape con- trol system have achieved significant progress. In the aspect of shape control models, the researches in the past improve the accuracy, speed and robustness of the models. The intelligentization of shape control models should be strengthened in the future. In the aspect of the shape control means, the researches in the past focus on the roll opti- mization, mill type selection, process optimization, local strip shape control, edge drop control, and so on. In the future, more attention should be paid to the coordination control of both strip shape and other quality indexes, and the refinement of control objective should be strengthened. In the aspects of shape detection technology and shape control system, some new types of shape detection meters and shape control systems are developed and have successfully indus- trial applications. In the future, the standardization of shape detection technology and shape control system should be promoted to solve the problem of compatibility. In general,the four expected development trends of shape control for cold roiling strip in the future are intelligentization, coordi- nation, refinement, and standardization. The proposed research provides new breakthrough directions for improv- ing shape quality. 展开更多
关键词 Cold rolling strip - Shape control Development trend theory models Shape detectionControl system
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