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The Nonlinear Lopsided HSS-Like Modulus-Based Matrix Splitting Iteration Method for Linear Complementarity Problems with Positive-Definite Matrices
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作者 Lu Jia Xiang Wang Xiao-Yong Xiao 《Communications on Applied Mathematics and Computation》 2021年第1期109-122,共14页
In this paper,by means of constructing the linear complementarity problems into the corresponding absolute value equation,we raise an iteration method,called as the nonlinear lopsided HSS-like modulus-based matrix spl... In this paper,by means of constructing the linear complementarity problems into the corresponding absolute value equation,we raise an iteration method,called as the nonlinear lopsided HSS-like modulus-based matrix splitting iteration method,for solving the linear complementarity problems whose coefficient matrix in R^(n×n)is large sparse and positive definite.From the convergence analysis,it is appreciable to see that the proposed method will converge to its accurate solution under appropriate conditions.Numerical examples demonstrate that the presented method precede to other methods in practical implementation. 展开更多
关键词 Linear complementarity problem modulus-based matrix splitting Lopsided HSS
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Modulus-Based Matrix Splitting Iteration Methods for a Class of Stochastic Linear Complementarity Problem
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作者 Qianqian Lu Chenliang Li 《American Journal of Operations Research》 2019年第6期245-254,共10页
For the expected value formulation of stochastic linear complementarity problem, we establish modulus-based matrix splitting iteration methods. The convergence of the new methods is discussed when the coefficient matr... For the expected value formulation of stochastic linear complementarity problem, we establish modulus-based matrix splitting iteration methods. The convergence of the new methods is discussed when the coefficient matrix is a positive definite matrix or a positive semi-definite matrix, respectively. The advantages of the new methods are that they can solve the large scale stochastic linear complementarity problem, and spend less computational time. Numerical results show that the new methods are efficient and suitable for solving the large scale problems. 展开更多
关键词 Stochastic Linear Complementarity Problem modulus-based matrix splitting EXPECTED Value Formulation Positive Semi-Definite matrix
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On the Convergence of Two-Step Modulus-Based Matrix Splitting Iteration Methods for a Restricted Class of Nonlinear Complementarity Problems with H_(+) -Matrices 被引量:2
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作者 Rui Li Yan Wang Junfeng Yin 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE CSCD 2018年第1期128-139,共12页
We propose the two-step modulus-based matrix splitting iteration methods for a class of nonlinear complementarity problems.The corresponding convergence the-ory is established when the system matrix is an H_(+)-matrix... We propose the two-step modulus-based matrix splitting iteration methods for a class of nonlinear complementarity problems.The corresponding convergence the-ory is established when the system matrix is an H_(+)-matrix.Theoretical analysis gives the choice of parameter matrix involved based on the H-compatible splitting of the sys-tem matrix.Moreover,in actual implementation,the choices of iterative parameters for two-step modulus-based accelerated overrelaxation methods are studied.Numeri-cal experiments show that the method is efficient and further verify the convergence theorems. 展开更多
关键词 Nonlinear complementarity problems two-step modulus-based matrix splitting meth-ods H_(+)-matrix H-compatible splitting
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Comparative analysis of energy-level splitting of Pr^(3+) doped in LiYF_4 and LiBiF_4 crystals:a complete energy matrix calculation
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作者 段美玲 邝小渝 +1 位作者 张彩霞 柴瑞鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期296-303,共8页
Based on the combination of Racah's group-theoretical consideration with Slater's wavefunction, a 91 ×91 complete energy matrix is established in tetragonal ligand field D2d for Pr3+ ion. Thus, the Stark energ... Based on the combination of Racah's group-theoretical consideration with Slater's wavefunction, a 91 ×91 complete energy matrix is established in tetragonal ligand field D2d for Pr3+ ion. Thus, the Stark energy-levels of Pr3+ ions doped separately in LiYF4 and LiBiF4 crystals are calculated, and our calculations imply that the complete energy matrix method can be used as an effective tool to calculate the energy-levels of the systems doped by rare earth ions. Besides, the influence of Pr3+ on energy-level splitting is investigated, and the similarities and the differences between the two doped crystals are demonstrated in detail by comparing their several pairs of curves and crystal field strength quantities. We see that the energy splitting patterns are similar and the crystal field interaction of LiYF4:Pr3+ is stronger than that of LiBiF4:Pr3+. 展开更多
关键词 energy levels splitting rare earth ions complete energy matrix
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THE SPECTRAL PROPERTIES OF THE ITERATION MATRIX OF REGULAR SPLITTINGS FOR AN M-MATRIX
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作者 黎稳 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1995年第1期31-36,共6页
Let A=M-N be a regular splitting of an M-matrix. We study the spectral properties of the ineration matrix M-1N. Under a mild assumption on M-1 N. some necessary and sufficent conditions such that p(M-1N)=1 are obtaine... Let A=M-N be a regular splitting of an M-matrix. We study the spectral properties of the ineration matrix M-1N. Under a mild assumption on M-1 N. some necessary and sufficent conditions such that p(M-1N)=1 are obtained and the algebraic multiplicity and the index associated with eigenvalue 1 in M-1N are considered. 展开更多
关键词 M-matrix REGULAR splitting imalrix algebraic MULTIPLICITY of SPECTRAL redius index of SPECTRAL radius
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SIGN MATRIX, REGULAR SPLITTINGS AND MONOTONIC ENCLOSURE OF SOLUTIONS FOR NONLINEAR SYSTEM OF EQUATIONS, PARTI
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作者 徐宗本 游兆永 《高校应用数学学报(A辑)》 CSCD 北大核心 1992年第1期139-146,共8页
In this paper we introduce the sign matrix of a nonlinear system of equations x = Gx to characterize its hybrid and asynchronous monotonicity as well as convexity. Based on the configuration of the matrix, we define a... In this paper we introduce the sign matrix of a nonlinear system of equations x = Gx to characterize its hybrid and asynchronous monotonicity as well as convexity. Based on the configuration of the matrix, we define a new type of regular splittings of the system with which the solvability and construction of solutions for the system are transformed to those of the couple systems of the splitting formIt is shown that this couple systems is a general model for developing monotonic enclosure methods of solutions for various types of nonlinear system of equations. 展开更多
关键词 SIGN matrix REGULAR splitting MONOTONIC ENCLOSURE Ordered Convexity Iterative Procedure under Partial Ordering.
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BANDED M-MATRIX SPLITTING PRECONDITIONER FOR RIESZ SPACE FRACTIONAL REACTION-DISPERSION EQUATION
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作者 Shiping Tang Aili Yang Yujiang Wu 《Journal of Computational Mathematics》 SCIE CSCD 2024年第2期372-389,共18页
Based on the Crank-Nicolson and the weighted and shifted Grunwald operators,we present an implicit difference scheme for the Riesz space fractional reaction-dispersion equations and also analyze the stability and the ... Based on the Crank-Nicolson and the weighted and shifted Grunwald operators,we present an implicit difference scheme for the Riesz space fractional reaction-dispersion equations and also analyze the stability and the convergence of this implicit difference scheme.However,after estimating the condition number of the coefficient matrix of the discretized scheme,we find that this coefficient matrix is ill-conditioned when the spatial mesh-size is sufficiently small.To overcome this deficiency,we further develop an effective banded M-matrix splitting preconditioner for the coefficient matrix.Some properties of this preconditioner together with its preconditioning effect are discussed.Finally,Numerical examples are employed to test the robustness and the effectiveness of the proposed preconditioner. 展开更多
关键词 Riesz space fractional equations Toeplitz matrix conjugate gradient method Incomplete Cholesky decomposition Banded M-matrix splitting
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Preconditioned Iterative Method for Regular Splitting 被引量:1
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作者 Toshiyuki Kohno 《Advances in Pure Mathematics》 2017年第2期180-187,共8页
Several preconditioners are proposed for improving the convergence rate of the iterative method derived from splitting. In this paper, the comparison theorem of preconditioned iterative method for regular splitting is... Several preconditioners are proposed for improving the convergence rate of the iterative method derived from splitting. In this paper, the comparison theorem of preconditioned iterative method for regular splitting is proved. And the convergence and comparison theorem for any preconditioner are indicated. This comparison theorem indicates the possibility of finding new preconditioner and splitting. The purpose of this paper is to show that the preconditioned iterative method yields a new splitting satisfying the regular or weak regular splitting. And new combination preconditioners are proposed. In order to denote the validity of the comparison theorem, some numerical examples are shown. 展开更多
关键词 ITERATIVE METHOD splitting PRECONDITIONER M-matrix
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宫颈癌调强计划Portal Dosimetry剂量验证中拼接野的应用分析
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作者 时飞跃 吕懂霞 +5 位作者 付林 庄洁颖 王敏 秦伟 赵环宇 魏晓为 《中国医疗设备》 2024年第10期73-78,共6页
目的提出一种生成Portal Dosimetry(以下简称PD)分野的拼接野(以下简称PD拼接野)方法,并对宫颈癌计划的PD拼接野进行分析研究。方法选取20例宫颈癌患者的七野调强治疗计划进行研究,治疗计划中每个大野分成1对分野。首先制作仅含分野的P... 目的提出一种生成Portal Dosimetry(以下简称PD)分野的拼接野(以下简称PD拼接野)方法,并对宫颈癌计划的PD拼接野进行分析研究。方法选取20例宫颈癌患者的七野调强治疗计划进行研究,治疗计划中每个大野分成1对分野。首先制作仅含分野的PD剂量验证计划,然后使用直线加速器出束执行。通过矩阵拼接和矩阵叠加,分别得到每对PD分野对应的PD拼接野和PD大野。使用PD软件模块,得到PD拼接野和PD大野的伽玛通过率,分别记为Gp和Gd。使用Gm表示每对PD分野的平均伽玛通过率值。对Gp、Gd和Gm进行统计分析和比较研究。结果所有140个射野的Gp、Gd和Gm的值分别为98.78%±0.70%、97.34%±1.25%和98.87%±0.51%。两两比较结果显示,Gp和Gd差异具有统计学意义(P<0.05);Gp和Gm的数据差异较小。对每个PD验证计划,计算所有同一类射野对应的计划验证通过率(Gplan)。对Gplan数据进行统计分析显示,PD拼接野和PD大野差异具有统计学意义(P<0.05),PD拼接野和PD分野的数据差异较小。结论本文提出的PD拼接野概念为评价PD剂量验证结果提供了有益的参考信息。 展开更多
关键词 宫颈癌 分野 拼接野 伽玛通过率 Portal Dosimetry 调强放射治疗 矩阵拼接
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关于矩阵三种典型分裂及应用
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作者 任芳国 王甜甜 《高等数学研究》 2024年第2期44-47,65,共5页
本文讨论了矩阵的Cartesian分裂、Jordan分裂、核心-幂零分裂的存在性与唯一性;将Jordan块的主要特性推广到一般矩阵;获得了一般矩阵具有的性质.以上关于矩阵分裂结果充实并深化了矩阵分裂的已有结果,并有助于提高学生学习高等代数及矩... 本文讨论了矩阵的Cartesian分裂、Jordan分裂、核心-幂零分裂的存在性与唯一性;将Jordan块的主要特性推广到一般矩阵;获得了一般矩阵具有的性质.以上关于矩阵分裂结果充实并深化了矩阵分裂的已有结果,并有助于提高学生学习高等代数及矩阵分析理论与应用的能力,以便为利用矩阵理论解决实际问题奠定了基础. 展开更多
关键词 矩阵分裂 正交矩阵 酉矩阵 Jordan矩阵 矩阵的指标
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多元统计分析中一类矩阵迹函数极小化问题的分裂迭代法
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作者 段强 周学林 李姣芬 《工程数学学报》 CSCD 北大核心 2024年第3期507-524,共18页
研究了来源于多元统计分析中的一类含列正交约束的矩阵迹函数极小化模型,该模型的特殊形式广泛应用于多维标度分析中DEDICOM模型和正交INDSCAL模型最小二乘拟合等问题中。结合变量分裂构造了几类经典的基于分裂的不可行迭代算法求解该... 研究了来源于多元统计分析中的一类含列正交约束的矩阵迹函数极小化模型,该模型的特殊形式广泛应用于多维标度分析中DEDICOM模型和正交INDSCAL模型最小二乘拟合等问题中。结合变量分裂构造了几类经典的基于分裂的不可行迭代算法求解该约束迹函数极小化模型,并给出算法外层迭代框架和内层子问题的具体求解方案。数值实验验证了算法的有效性。 展开更多
关键词 正交分裂 矩阵迹函数 正交约束 增广拉格朗日方法
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碳基跨尺度纤维增强混凝土劈拉性能及微观界面研究
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作者 夏伟 张彤 +3 位作者 白二雷 陆松 吴昊 秦立军 《化工新型材料》 CAS CSCD 北大核心 2024年第7期245-249,共5页
为改善碳纤维增强混凝土(CFRC)内部的纤维/基体(F/M)界面性能,提出利用碳纳米管-碳纤维跨尺度增强体(CNTs-CF)对F/M微观界面进行改性的技术方法。设计制作了CNTs-CF体积分数分别为0%、0.1%、0.2%、0.3%和0.4%的跨尺度纤维增强混凝土(CCF... 为改善碳纤维增强混凝土(CFRC)内部的纤维/基体(F/M)界面性能,提出利用碳纳米管-碳纤维跨尺度增强体(CNTs-CF)对F/M微观界面进行改性的技术方法。设计制作了CNTs-CF体积分数分别为0%、0.1%、0.2%、0.3%和0.4%的跨尺度纤维增强混凝土(CCFRC)试件,进而对其开展了劈裂抗拉实验,并与CFRC进行对比分析。结果表明,在相同的纤维掺量情况下,CCFRC能够在劈拉破坏失效时维持更好的整体性,而且CCFRC的劈裂抗拉强度明显高于CFRC。CCFRC的劈裂抗拉强度随纤维掺量的增加呈先逐渐升高后略有下降的变化趋势,当CNTs-CF的体积分数为0.3%时达到最大值,较之普通混凝土(PC)和CFRC,增长幅度分别达37.67%和13.21%。CNTs-CF兼具碳纤维和碳纳米管的优良特性,能够充分发挥跨尺度协同改性效应,强化F/M界面。CCFRC在工程结构抗力提升,以及基础设施电磁防护领域具有广阔的应用发展前景。 展开更多
关键词 混凝土 碳基跨尺度纤维 劈裂抗拉强度 纤维/基体界面 协同改性
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Another SSOR Iteration Method
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作者 Thomas Smotzer John Buoni 《American Journal of Computational Mathematics》 2024年第2期248-256,共9页
Kellogg gave a version of the Peaceman-Radford method. In this paper, we introduce a SSOR iteration method which uses Kellogg’s method. The new algorithm has some advantages over the traditional SSOR algorithm. A Cyc... Kellogg gave a version of the Peaceman-Radford method. In this paper, we introduce a SSOR iteration method which uses Kellogg’s method. The new algorithm has some advantages over the traditional SSOR algorithm. A Cyclic Reduction algorithm is introduced via a decoupling in Kellogg’s method. 展开更多
关键词 matrix splitting SSOR Iteration KSSOR Iteration Method Kellogg-Type SSOR Iteration Cyclic Reduction
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求解PageRank向量的一种松弛多步分裂迭代方法
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作者 田兆禄 王玉栋 刘仲云 《工程数学学报》 CSCD 北大核心 2024年第4期642-658,共17页
基于求解PageRank向量的内外迭代格式,引入一个松弛因子得到一种松弛内外迭代方法。结合已有的多步分裂迭代框架,引入两个不同的松弛因子,提出了求解PageRank向量的松弛多步分裂迭代方法并分析了算法的收敛性。更进一步地,利用松弛内外... 基于求解PageRank向量的内外迭代格式,引入一个松弛因子得到一种松弛内外迭代方法。结合已有的多步分裂迭代框架,引入两个不同的松弛因子,提出了求解PageRank向量的松弛多步分裂迭代方法并分析了算法的收敛性。更进一步地,利用松弛内外迭代格式构造了加速投影子空间方法的预处理矩阵,理论分析相关谱分布情况,并给出了松弛多步分裂迭代方法及预处理矩阵中参数的选取准则。几个数值例子验证了松弛多步分裂迭代方法和预处理矩阵的有效性,通过选取合适的松弛因子,与多步分裂迭代方法相比具有更高的运算效率。 展开更多
关键词 PageRank向量 多步分裂迭代方法 松弛因子 迭代矩阵 最优参数
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基于分离源的高增益矩阵变换器特性分析
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作者 程启明 张昕 +2 位作者 程尹曼 赖宇生 沈章平 《电力自动化设备》 EI CSCD 北大核心 2024年第4期67-73,共7页
针对矩阵变换器(MC)存在的电压传输比限制以及现有升压型MC结构元件多、调制复杂的问题,提出了一种新型的分离源型矩阵变换器(SS-MC)。该结构采用电感、电容和3个二极管替代了双级MC中间的直流链路部件,从而构成分离源升压网络,避免了... 针对矩阵变换器(MC)存在的电压传输比限制以及现有升压型MC结构元件多、调制复杂的问题,提出了一种新型的分离源型矩阵变换器(SS-MC)。该结构采用电感、电容和3个二极管替代了双级MC中间的直流链路部件,从而构成分离源升压网络,避免了配置额外的直通占空比。对SS-MC的拓扑结构和分离源网络升压的工作原理进行了分析,阐述了其采用的空间矢量脉宽调制(SVPWM)策略,并针对SVPWM的缺点提出了基于充电预测的模型预测控制(CPB-MPC)策略。仿真和实验结果表明:所提出的SS-MC结构使用常规的SVPWM即可达到较高的电压传输比,但无源元件会存在较大的纹波;使用CPB-MPC策略可以有效抑制纹波,提高MC的输出电能质量。 展开更多
关键词 矩阵变换器 电压传输比 分离源 空间矢量脉宽调制 模型预测控制
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基于分离源矩阵变换器的PMSM无源动态演化控制策略
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作者 程启明 罗力珲 +3 位作者 沈治超 王为涛 张梁 王海伦 《高电压技术》 EI CAS CSCD 北大核心 2024年第5期2030-2041,共12页
为了改进传统的永磁同步电机驱动器系统及其PID控制的不足,提出了一种无源动态演化控制策略,并应用于永磁同步电机(permanent magnet synchronous motor,PMSM)和分离源矩阵变换器(split source matrix con-verter,SSMC)中。为打破传统... 为了改进传统的永磁同步电机驱动器系统及其PID控制的不足,提出了一种无源动态演化控制策略,并应用于永磁同步电机(permanent magnet synchronous motor,PMSM)和分离源矩阵变换器(split source matrix con-verter,SSMC)中。为打破传统矩阵变换器电压传输比0.866的限制,采用电感、电容和3个二极管代替了双级矩阵变换器中间的支流链路部件,并且证明了分离源网络的升压能力。另外,在矢量控制中,永磁同步电机的转速外环和电流内环都使用了传统PID控制器,但由于PID控制器的参数调节比较困难、控制精度不高、超调量较大和抗干扰能力不强等问题,为此提出了基于动态演化理论和无源理论的控制策略,设计了分离源矩阵变换器和永磁同步电机系统基于互联和阻尼分配(the interconnection and damping assignment,IDA)的无源控制器(passivity-based control,PBC)和动态演化控制器(dynamic evolution controller,DEC)。仿真与实验的结果表明,基于该控制策略的SSMC-PMSM驱动系统能够使永磁同步电机稳定运行在额定转速,并且具有稳定性强、抗干扰能力强和动态响应好等特点。 展开更多
关键词 分离源矩阵变换器 电压传输比 永磁同步电机 无源理论 动态演化理论 PID控制
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异体脱细胞真皮基质复合自体刃厚皮片移植在面颈部烧伤后期瘢痕挛缩整形中的应用效果
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作者 王栋 王政刚 +4 位作者 丁金艳 毛宇峰 李小龙 张龙杰 桑晨 《当代医学》 2024年第7期32-35,共4页
目的分析异体脱细胞真皮基质(ADM)复合自体刃厚皮片移植在面颈部烧伤后期瘢痕挛缩整形中的应用效果。方法选取2018年1月至2022年4月诸城市人民医院收治的45例面颈部烧伤后期瘢痕挛缩患者作为研究对象,按照整形修复方案分为对照组(n=22)... 目的分析异体脱细胞真皮基质(ADM)复合自体刃厚皮片移植在面颈部烧伤后期瘢痕挛缩整形中的应用效果。方法选取2018年1月至2022年4月诸城市人民医院收治的45例面颈部烧伤后期瘢痕挛缩患者作为研究对象,按照整形修复方案分为对照组(n=22)与观察组(n=23),两组均切除面颈部瘢痕组织并松解挛缩,对照组接受自体中厚皮片移植,观察组接受ADM复合自体刃厚皮片移植。比较两组皮片成活率、二次手术率、创面感染率、植皮区及供皮区愈合时间、创面修复效果、颏颈角及颈部主动活动度的矫正度数。结果观察组皮片成活率高于对照组,差异有统计学意义(P<0.05);两组二次手术率、创面感染率比较差异均无统计学意义。两组植皮区愈合时间比较差异无统计学意义;观察组供皮区愈合时间短于对照组,差异有统计学意义(P<0.05)。术后6个月,两组皮肤柔软度、厚度、色泽、血管分布评分均低于术后3个月,差异有统计学意义(P<0.05);两组术后3、6个月皮肤柔软度、厚度、色泽、血管分布评分比较差异无统计学意义。两组术后6个月颏颈角及颈部主动活动度的矫正度数比较差异均无统计学意义。结论面颈部烧伤后期瘢痕挛缩整形中应用ADM复合自体刃厚皮片移植的整形修复效果与自体中厚皮片移植相近,然而复合移植的皮片成活率更高,供皮区愈合时间更短。 展开更多
关键词 异体脱细胞真皮基质 自体刃厚皮片 复合移植 面颈部烧伤 瘢痕挛缩
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基于多电源并列运行的输配电网故障诊断的改进方法研究
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作者 宋春雯 《自动化应用》 2024年第4期37-38,42,共3页
为有效定位输配电网的故障区段,提升调度应急处置工作的针对性和有效性,在多电源并列运行故障诊断的矩阵算法基础上,提出了基于网络拆分的故障诊断优化方法。通过多重故障场景测试分析,当存在告警信息畸变时,该方法尽管因广度优先搜索... 为有效定位输配电网的故障区段,提升调度应急处置工作的针对性和有效性,在多电源并列运行故障诊断的矩阵算法基础上,提出了基于网络拆分的故障诊断优化方法。通过多重故障场景测试分析,当存在告警信息畸变时,该方法尽管因广度优先搜索分块会浪费一定的时效性,但其容错性好,可有效解决多重故障诊断的问题。 展开更多
关键词 多电源并列运行 故障诊断 矩阵算法 网络拆分
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TWO-STEP MODULUS-BASED SYNCHRONOUS MULTISPLITTING ITERATION METHODS FOR LINEAR COMPLEMENTARITY PROBLEMS 被引量:11
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作者 Lili Zhang 《Journal of Computational Mathematics》 SCIE CSCD 2015年第1期100-112,共13页
To reduce the communication among processors and improve the computing time for solving linear complementarity problems, we present a two-step modulus-based syn- chronous multisplitting iteration method and the corres... To reduce the communication among processors and improve the computing time for solving linear complementarity problems, we present a two-step modulus-based syn- chronous multisplitting iteration method and the corresponding symmetric modulus-based multisplitting relaxation methods. The convergence theorems are established when the system matrix is an H+-matrix, which improve the existing convergence theory. Numeri- cal results show that the symmetric modulus-based multisplitting relaxation methods are effective in actual implementation. 展开更多
关键词 Linear complementarity problem modulus-based method matrix multisplit-ring Convergence.
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Analysis of Adiabatic Shearing Failure Mechanism for Aluminum Matrix Composites Based on Experimental and Numerical Simulation 被引量:1
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作者 郑振兴 朱德智 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第5期892-896,共5页
Adiabatic shear behavior and the corresponding mechanism of TiB2/Al composites were researched by split Hopkinson pressure bar (SHPB).Results show that the flow stresses of the TiB2/Al composites exhibit softening t... Adiabatic shear behavior and the corresponding mechanism of TiB2/Al composites were researched by split Hopkinson pressure bar (SHPB).Results show that the flow stresses of the TiB2/Al composites exhibit softening tendency with the increasing of strain rates. All the composites fail in splitting and cutting with a 45 degree, and the phase transformed bands of molten aluminum are found on the adiabatic shear layers. The deformation behavior and shear localization of the TiB2/Al composites specimens were simulated by finite element code MSC.Marc. The Johnson-Cook model was used to describe the thermo-viscoplastic response of the specimen material. There was unanimous between the numerical result and the experimental result on the location of the adiabatic shear band. From the numerical simulation and experiment, it was concluded that the instantaneous failure of the composite was ascribed due to the local low strength area where the formation of adiabatic shear band was, and the stress condition had significant effect on the initiation and propagation of adiabatic shear band (ASB). 展开更多
关键词 metal matrix composites split Hopkinson pressure bar high strain-rate adiabatic shear band Johnson-Cook model
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