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永磁同步电机电机本体数学模型在MATLAB下的仿真 被引量:21
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作者 张红生 吴炳娇 《自动化与仪器仪表》 2012年第2期134-135,138,共3页
在电机的应用中,永磁同步电机的数学模型可以是在d/q模型或者a b c模型下建立。本文为了更好地实现永磁同步电机的矢量控制,在永磁同步电机的电压、电流、磁链的关系表达式基础上,运用MATLAB建立了其数学模型下的仿真模型,并结合park和c... 在电机的应用中,永磁同步电机的数学模型可以是在d/q模型或者a b c模型下建立。本文为了更好地实现永磁同步电机的矢量控制,在永磁同步电机的电压、电流、磁链的关系表达式基础上,运用MATLAB建立了其数学模型下的仿真模型,并结合park和clarke变换对所建立的数学仿真模型进行了验证。仿真结果表明所建立的永磁同步电机模型的正确性。由此为永磁同步电机的调速问题提供了更简化的模型和更广泛的应用范围。 展开更多
关键词 永磁同步电机 磁链 clarke PARK 矢量控制
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“选址—路线”问题的建模与算法研究 被引量:4
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作者 张静 刘鲁 陈安 《北京航空航天大学学报(社会科学版)》 2002年第1期33-37,共5页
建立了“选址—路线”问题的数学模型 ,并且给出了求解问题的启发式算法。该启发式算法是基于改进的Clarke Wright算法和旅行推销员问题。在账单递送的实际案例中 ,这种启发式算法 ,和传统手工方法相比 ,求解速度更快 ,同时降低了运作成... 建立了“选址—路线”问题的数学模型 ,并且给出了求解问题的启发式算法。该启发式算法是基于改进的Clarke Wright算法和旅行推销员问题。在账单递送的实际案例中 ,这种启发式算法 ,和传统手工方法相比 ,求解速度更快 ,同时降低了运作成本 。 展开更多
关键词 选址-路线 clarke and Wright算法 案例研究
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Clarke和Park变换在DSP上的实现 被引量:5
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作者 石燕宏 金元浩 闫士杰 《基础自动化》 CSCD 2000年第2期14-16,共3页
介绍了通过 Clarke和 Park变换 ,可将静止坐标系中三相交流电流 ia、ib和 ic变换成静止坐标系中的二相交流电流 iα、iβ,再将 iα、iβ 变换成与转子磁链同步旋转的坐标系中的二相直流电流 isb、isq,给出 Clarke和Park变换的数学表达... 介绍了通过 Clarke和 Park变换 ,可将静止坐标系中三相交流电流 ia、ib和 ic变换成静止坐标系中的二相交流电流 iα、iβ,再将 iα、iβ 变换成与转子磁链同步旋转的坐标系中的二相直流电流 isb、isq,给出 Clarke和Park变换的数学表达式 ,在数据信号处理器 ( DSP) TMS3 2 0 C2 4 0上实现了该种变换。 展开更多
关键词 磁场定向控制 clarke PARK 矢量控制系统 DSP
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短波无线信道特性的计算方法及其仿真 被引量:6
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作者 李志强 徐锋 +2 位作者 李杰英 颜伟 张春晶 《火力与指挥控制》 CSCD 北大核心 2014年第S1期55-58,共4页
介绍了短波无线信道的传播特性,重点介绍了短波信道的损耗特性,给出了短波在天波传输和地波传输两种方式下的损耗特性的估算方法,分析了短波小尺度衰落时采用的Clarke和Jakes仿真模型。采用MATLAB软件仿真了短波在天波传输方式下的大尺... 介绍了短波无线信道的传播特性,重点介绍了短波信道的损耗特性,给出了短波在天波传输和地波传输两种方式下的损耗特性的估算方法,分析了短波小尺度衰落时采用的Clarke和Jakes仿真模型。采用MATLAB软件仿真了短波在天波传输方式下的大尺度衰落特性、小尺度衰落特性和误码率特性,得到了短波通信时的中值衰落波形、总衰落波形和误码率仿真结果,可以为外场试验提供参考数据,为联合仿真提供短波信道物理层特性。 展开更多
关键词 短波信道 clarke Jakes 衰落特性 MATLAB
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Differential Evolution Hemivariational Inequalities with Anti-periodic Conditions 被引量:1
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作者 Jing ZHAO Chun Mei GAN Zhen Hai LIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第4期1143-1160,共18页
The goal of this paper is to deal with a new dynamic system called a differential evolution hemivariational inequality(DEHVI)which couples an abstract parabolic evolution hemivariational inequality and a nonlinear dif... The goal of this paper is to deal with a new dynamic system called a differential evolution hemivariational inequality(DEHVI)which couples an abstract parabolic evolution hemivariational inequality and a nonlinear differential equation in a Banach space.First,by apply ing surjectivity result for pseudomonotone multivalued mappins and the properties of Clarke's subgradient,we show the nonempty of the solution set for the parabolic hemivariational inequality.Then,some topological properties of the solution set are established such as boundedness,closedness and convexity.Furthermore,we explore the upper semicontinuity of the solution mapping.Finally,we prove the solution set of the system(DEHVI)is nonempty and the set of all trajectories of(DEHVI)is weakly compact in C(I,X). 展开更多
关键词 Differential parabolic hemivariational inequality clarke subdifferential hyperbolicparabolic system parabolic-parabolic system existence result
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非光滑半无限多目标优化问题的最优性充分条件 被引量:4
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作者 杨玉红 李飞 《应用数学和力学》 CSCD 北大核心 2017年第5期526-538,共13页
研究了一个非光滑半无限多目标优化问题(简记为SIMOP),并讨论了它的最优性条件.首先,通过对目标函数和约束函数的某种组合赋予Clarke F-凸性假设,获得了SIMOP(弱)有效解的最优性充分条件.接下来,用Chankong-Haimes方法建立了此SIMOP的... 研究了一个非光滑半无限多目标优化问题(简记为SIMOP),并讨论了它的最优性条件.首先,通过对目标函数和约束函数的某种组合赋予Clarke F-凸性假设,获得了SIMOP(弱)有效解的最优性充分条件.接下来,用Chankong-Haimes方法建立了此SIMOP的一个标量问题并得到了这个标量问题的最优性充分条件. 展开更多
关键词 半无限多目标优化 (弱)有效解 最优性条件 clarke F-凸性
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Main Patterns of Geochemistry of Phosphorus
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作者 Yakov Elievich Yudovich Marina Petrovna Ketris Natalia Valerievna Rybina 《International Journal of Geosciences》 2023年第10期955-998,共44页
The paper presents the main conclusions of the Russian monograph “Geochemistry of Phosphorus” (2020). Based on statistical processing of ~6100 sample averages (from ~190,000 analyses), new estimations of World avera... The paper presents the main conclusions of the Russian monograph “Geochemistry of Phosphorus” (2020). Based on statistical processing of ~6100 sample averages (from ~190,000 analyses), new estimations of World averages (Clarke values) for Р<sub>2</sub>O<sub>5</sub>, % (and P, %), phosphorus-titanium module (P<sub>2</sub>О<sub>5</sub>/TiO<sub>2</sub>), phosphorus-calcium module (P<sub>2</sub>O<sub>5</sub>/CaO), phosphorus-iron module (P<sub>2</sub>О<sub>5</sub>/Fe<sub>2</sub>O<sub>3</sub>), and phosphorus-total iron module (P<sub>2</sub>O<sub>5</sub>/Fe<sub>2</sub>O<sub>3</sub> + FeO). Many estimates have been made for the first time. In addition to the new Clarke estimates, sometimes very different from previous ones, the work carried out has led to a number of new conclusions. In particular, the titanium geochemical barrier for phosphorus has been first estimated, all the 11 genotypes of phosphogenesis have been named and characterized, five genetic correlations of phosphogenesis have been described, lithochemistry methods have been successfully applied to characterize the phosphorites. Due to the large breadth of generalization, the monograph has a large theoretical and applied value. 展开更多
关键词 PHOSPHORUS GEOCHEMISTRY PHOSPHORITES Lithochemistry clarke Values (World Average Contents)
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非光滑半无限多目标优化问题的对偶性 被引量:2
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作者 杨玉红 唐莉萍 《系统科学与数学》 CSCD 北大核心 2017年第7期1633-1645,共13页
研究了一个非光滑半无限多目标优化问题(简记为SIMOP)并讨论它的对偶性.本文重点考虑此SIMOP的Mond-Weir型半无限多目标对偶问题,通过对目标函数和约束函数的某种组合赋予Clarke-凸性假设,获得了弱/强/逆对偶结论.文章的一些结论是比较... 研究了一个非光滑半无限多目标优化问题(简记为SIMOP)并讨论它的对偶性.本文重点考虑此SIMOP的Mond-Weir型半无限多目标对偶问题,通过对目标函数和约束函数的某种组合赋予Clarke-凸性假设,获得了弱/强/逆对偶结论.文章的一些结论是比较新的,并推广了已有文献的一些结果. 展开更多
关键词 半无限多目标优化 对偶性 (弱)有效解 clarke F-凸性.
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基于DSP的三相混合式步进电机的SVPWM控制 被引量:1
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作者 付涛歧 吴玉国 《机电产品开发与创新》 2008年第4期142-144,共3页
提出了基于DSP的三相混合式步进电机电压空间矢量SVPWM控制方法。通过对三相步进电机旋转磁场的空间电流矢量合成以及Clarke、Park变换,使绕组中电流在细分控制下得到了较好的电流正弦波形,实现恒转矩控制。实验结果表明,SVPWM控制系统... 提出了基于DSP的三相混合式步进电机电压空间矢量SVPWM控制方法。通过对三相步进电机旋转磁场的空间电流矢量合成以及Clarke、Park变换,使绕组中电流在细分控制下得到了较好的电流正弦波形,实现恒转矩控制。实验结果表明,SVPWM控制系统极大的降低了步进电机低频振荡现象,改善了高速运行时的力矩特性。 展开更多
关键词 SVPWM 步进电机 DSP clarke PARK
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Strong convergence results for hemivariational inequalities 被引量:2
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作者 LIU Zhenhai ZOU Jiezhong 《Science China Mathematics》 SCIE 2006年第7期893-901,共9页
The purpose of this paper is to study a regularization method of solutions of ill-posed problems involving hemivariational inequalities in Banach spaces. Under the assumption that the hemivariational inequality is sol... The purpose of this paper is to study a regularization method of solutions of ill-posed problems involving hemivariational inequalities in Banach spaces. Under the assumption that the hemivariational inequality is solvable, a strongly convergent approximation procedure is designed by means of the so-called Browder-Tikhonov regularization method. Our results generalize and extend the previously known theorems. 展开更多
关键词 hemivariational inequalities clarke subdifferential regularization STRONG convergence.
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APPROXIMATE SUBDIFFERENTIALS AND NONSMOOTH ANALYSIS FINITE DIMENSIONS
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作者 WANG Yuntong (Nankai Institute of Mathematics,Tianjin 300071,China) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1992年第1期84-96,共13页
Ioffe’s approximate subdifferentials are reviewed and some of his resultsare generalized.An extension of the calculus of the approximate subdifferentials forthe sums to any finite number of functions is provided alon... Ioffe’s approximate subdifferentials are reviewed and some of his resultsare generalized.An extension of the calculus of the approximate subdifferentials forthe sums to any finite number of functions is provided along with a generalizationof the Dubovitzkii-Milyutin theorem.The presentation also indicates some of thelimitations of nonsmooth analysis and optimization.Restriction to the class offunction which is suitable for most of the purposes in nonsmooth optimization issuggested. 展开更多
关键词 APPROXIMATE SUBDIFFERENTIALS Dini SUBDIFFERENTIAL clarke generalized gradient CONTINGENT CONE clarke TANGENT CONE normal CONE regular function strong general position property SUBDIFFERENTIAL calculus
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Subdifferential Representation of Homogeneous Functions and Extension of Smoothness in Banach spaces 被引量:1
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作者 Fu Chun YANG Zhou WEI Dong WANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2010年第8期1535-1544,共10页
In this paper, we mainly consider proximal subdifferentials of lower semicontinuous functions defined on real Hilbert space and Clarke's subdifferentials of locally Lipschitzian functions defined on Banach space resp... In this paper, we mainly consider proximal subdifferentials of lower semicontinuous functions defined on real Hilbert space and Clarke's subdifferentials of locally Lipschitzian functions defined on Banach space respectively, and obtain the generalized Euler identity of homogenous functions. Then, by introducing a multifunction F, we extend the smoothness of sphere and differentiability of norm function in Banach space. 展开更多
关键词 Homogeneous function proximal subdifferential clarke's subdifferential Euler identity SMOOTHNESS
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Nonsingularity in second-order cone programming via the smoothing metric projector 被引量:1
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作者 WANG Yun 1,& ZHANG LiWei 2 1 College of Information Sciences and Engineering,Shandong Agricultural University,Tai’an 271018,China 2 Department of Applied Mathematics,Dalian University of Technology,Dalian 116024,China 《Science China Mathematics》 SCIE 2010年第4期1025-1038,共14页
Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of... Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of the Clarke's generalized Jacobian of the smoothing Karush-Kuhn-Tucker system,constructed by the smoothing metric projector,is equivalent to the strong second-order sufficient condition and constraint nondegeneracy,which is in turn equivalent to the strong regularity of the Karush-Kuhn-Tucker point.Moreover,this nonsingularity property guarantees the quadratic convergence of the corresponding smoothing Newton method for solving a Karush-Kuhn-Tucker point.Interestingly,the analysis does not need the strict complementarity condition. 展开更多
关键词 second-order cone programming problem SMOOTHING METRIC PROJECTOR B-subdifferential clarke’s generalized JACOBIAN SMOOTHING Newton method
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Effect of Different Size of Ground Cyanotis arachnoidea Particles on the Release of β-ecdysone 被引量:1
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作者 朱国栋 张易祥 +3 位作者 叶金云 吴成龙 于岚 杨霞 《Agricultural Science & Technology》 CAS 2011年第9期1318-1319,1326,共3页
[Objective] The aim was to investigate the influence of different size of ground Cyanotis arachnoidea C.B.Clarke particles on the release of β-ecdysone.[Method] The content of β-ecdysone extracted from Cyanotis arac... [Objective] The aim was to investigate the influence of different size of ground Cyanotis arachnoidea C.B.Clarke particles on the release of β-ecdysone.[Method] The content of β-ecdysone extracted from Cyanotis arachnoidea powders of different sizes was detected through HPLC,under the chromatographic conditions:GRACE ODS C18 column(250 mm × 4.6 mm,5 μm),mobile phase methanol:water= 40:60(V/V),column temperature 26 ℃,flow rate 1.0 ml/min and detection wavelength 248 nm.[Result] The extracted β-ecdysone from ultra-fine Cyanotis arachnoidea powder(particle size 10,30 and 50 μm) was as more than two folds as common powder(particle size 180 μm).[Conclusion] The β-ecdysone in ultra-fine powder of Cyanotis arachnoidea was more easily soluble in methanol.The extraction rate of β-ecdysone was significantly higher than that of common powder.The result showed that the technology of ultra-fine pulverization markedly improved the dissolution of the β-ecdysone for increasing the cell breakage rate,and then the active ingredients could be extracted more easily. 展开更多
关键词 HPLC~ Cyanotis arachnoidea C. B. clarke β-ecdysone
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珠三角地区稻田周边杂草的群落分析 被引量:1
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作者 魏武 张丹琳 +2 位作者 王锐 陈海东 张文军 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第3期89-92,共4页
对珠三角地区的中山、东莞、珠海和广州市的稻田周边杂草群落进行研究,调查群落的多样性和均匀度。结果显示,珠三角地区稻田周边生境共有杂草25科,57种;中山稻田周边杂草多样性最低,均匀度最高,广州稻田周边杂草的多样性最高,但均匀度最... 对珠三角地区的中山、东莞、珠海和广州市的稻田周边杂草群落进行研究,调查群落的多样性和均匀度。结果显示,珠三角地区稻田周边生境共有杂草25科,57种;中山稻田周边杂草多样性最低,均匀度最高,广州稻田周边杂草的多样性最高,但均匀度最低;各地之间的群落结构存在显著差异。研究表明,稻田周边杂草群落多样性受工业化和农业集约化的影响;工业化和农业集约化程度高,杂草群落多样性越低。 展开更多
关键词 珠三角 杂草群落 多样性 均匀度 Rarefaction曲线 clarke R检验
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甘南高原野生与人工栽培翼首草根部多糖含量测定 被引量:1
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作者 丁耀光 马富花 付育红 《湖北农业科学》 北大核心 2014年第18期4361-4363,共3页
翼首草[Pterocephalus hookeri(Clarke)Hoeck]系川续断科翼首花属植物匙叶翼首花全草,富含植物多糖,块根可入药。通过超声波提取法从翼首草根部提取多糖,采用苯酚-硫酸比色法对其含量进行测定。结果表明,超声波提取的甘南高原野生翼首... 翼首草[Pterocephalus hookeri(Clarke)Hoeck]系川续断科翼首花属植物匙叶翼首花全草,富含植物多糖,块根可入药。通过超声波提取法从翼首草根部提取多糖,采用苯酚-硫酸比色法对其含量进行测定。结果表明,超声波提取的甘南高原野生翼首草的多糖含量为18.78 mg/100 mL,超声波提取的甘南高原人工栽培翼首草多糖含量为20.63 mg/100 mL,可见人工栽培翼首草根部多糖含量明显高于野生的。 展开更多
关键词 翼首草[Pterocephalus hookeri (clarke) Hoeck] 多糖含量 甘南高原 人工栽培
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Voltage and Current Mode Vector Analyses of Correction Procedure Application to Clarke’s Matrix—Symmetrical Three-Phase Cases 被引量:1
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作者 Afonso José do PRADO Sérgio KUROKAWA +1 位作者 José Pissolato FILHO Luiz Fernando BOVOLATO 《Journal of Electromagnetic Analysis and Applications》 2010年第1期7-17,共11页
Clarke’s matrix has been applied as a phase-mode transformation matrix to three-phase transmission lines substituting the eigenvector matrices. Considering symmetrical untransposed three-phase lines, an actual symmet... Clarke’s matrix has been applied as a phase-mode transformation matrix to three-phase transmission lines substituting the eigenvector matrices. Considering symmetrical untransposed three-phase lines, an actual symmetrical three-phase line on untransposed conditions is associated with Clarke’s matrix for error and frequency scan analyses in this paper. Error analyses are calculated for the eigenvalue diagonal elements obtained from Clarke’s matrix. The eigenvalue off-diagonal elements from the Clarke’s matrix application are compared to the correspondent exact eigenvalues. Based on the characteristic impedance and propagation function values, the frequency scan analyses show that there are great differences between the Clarke’s matrix results and the exact ones, considering frequency values from 10 kHz to 1 MHz. A correction procedure is applied obtaining two new transformation matrices. These matrices lead to good approximated results when compared to the exact ones. With the correction procedure applied to Clarke’s matrix, the relative values of the eigenvalue matrix off-diagonal element obtained from Clarke’s matrix are decreased while the frequency scan results are improved. The steps of correction procedure application are detailed, investigating the influence of each step on the obtained two new phase-mode transformation matrices. 展开更多
关键词 clarke’s Matrix EIGENVECTOR EIGENVALUE Phase Mode Transformation Error Analysis Non SYMMETRICAL LINES Frequency Dependent Parameters
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不可微函数的不变伪单调性与伪不变凸性(英文)
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作者 唐万梅 刘茜 杨新民 《运筹学学报》 CSCD 北大核心 2008年第3期50-58,共9页
本文讨论不可微函数的强伪不变凸性和不变伪单调性之间的关系,还讨论了不可微函数的伪不变凸性与半严格预拟不变凸性.此外,还给出了一个集值映射的不变伪单调的等价定义.
关键词 运筹学 数学规划 伪不变凸函数 不变伪单调 预拟不变凸函数 clarke’s 广义次可微映射
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ANALYSIS OF AN ELASTO-PIEZOELECTRIC SYSTEM OF HEMIVARIATIONAL INEQUALITIES WITH THERMAL EFFECTS
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作者 Pawel SZAFRANIEC 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期1048-1060,共13页
In this paper we prove the existence and uniqueness of a weak solution for a dynamic electo-viscoetastic problem that describes a contact between a body and a foundation. We assume the body is made from thermoviscoela... In this paper we prove the existence and uniqueness of a weak solution for a dynamic electo-viscoetastic problem that describes a contact between a body and a foundation. We assume the body is made from thermoviscoelastic material and consider nonmonotone boundary conditions for the contact. We use recent results from the theory of hemivariational inequalities and the fixed point theory. 展开更多
关键词 dynamic contact evolution hemivariational inequality clarke subdifferential NONCONVEX PARABOLIC viscoelastic material frictional contact weak solution PIEZOELECTRICITY
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Sufcient Conditions for Error Bounds and Linear Regularity in Banach Spaces
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作者 Zhou WEI Qing Hai HE 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2014年第3期423-436,共14页
In this paper, we study error bounds for lower semicontinuous functions defined on Banach space and linear regularity for finitely many closed subset in Banach spaces. By using Clarke's subd- ifferentials and Ekeland... In this paper, we study error bounds for lower semicontinuous functions defined on Banach space and linear regularity for finitely many closed subset in Banach spaces. By using Clarke's subd- ifferentials and Ekeland variational principle, we establish several sufficient conditions ensuring error bounds and linear regularity in Banach spaces. 展开更多
关键词 Error bound linear regularity normal cone clarke subdifferential Ekeland variationalprinciple
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