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Sequential quadratic programming-based non-cooperative target distributed hybrid processing optimization method 被引量:3
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作者 SONG Xiaocheng WANG Jiangtao +3 位作者 WANG Jun SUN Liang FENG Yanghe LI Zhi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期129-140,共12页
The distributed hybrid processing optimization problem of non-cooperative targets is an important research direction for future networked air-defense and anti-missile firepower systems. In this paper, the air-defense ... The distributed hybrid processing optimization problem of non-cooperative targets is an important research direction for future networked air-defense and anti-missile firepower systems. In this paper, the air-defense anti-missile targets defense problem is abstracted as a nonconvex constrained combinatorial optimization problem with the optimization objective of maximizing the degree of contribution of the processing scheme to non-cooperative targets, and the constraints mainly consider geographical conditions and anti-missile equipment resources. The grid discretization concept is used to partition the defense area into network nodes, and the overall defense strategy scheme is described as a nonlinear programming problem to solve the minimum defense cost within the maximum defense capability of the defense system network. In the solution of the minimum defense cost problem, the processing scheme, equipment coverage capability, constraints and node cost requirements are characterized, then a nonlinear mathematical model of the non-cooperative target distributed hybrid processing optimization problem is established, and a local optimal solution based on the sequential quadratic programming algorithm is constructed, and the optimal firepower processing scheme is given by using the sequential quadratic programming method containing non-convex quadratic equations and inequality constraints. Finally, the effectiveness of the proposed method is verified by simulation examples. 展开更多
关键词 non-cooperative target distributed hybrid processing multiple constraint minimum defense cost sequential quadratic programming
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Internal structural optimization of hollow fan blade based on sequential quadratic programming algorithm 被引量:1
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作者 YANG Jian-qiu WANG Yan-rong 《航空动力学报》 EI CAS CSCD 北大核心 2011年第4期787-793,共7页
Several structural design parameters for the description of the geometric features of a hollow fan blade were determined.A structural design optimization model of a hollow fan blade which based on the strength constra... Several structural design parameters for the description of the geometric features of a hollow fan blade were determined.A structural design optimization model of a hollow fan blade which based on the strength constraint and minimum mass was established based on the finite element method through these parameters.Then,the sequential quadratic programming algorithm was employed to search the optimal solutions.Several groups of value for initial design variables were chosen,for the purpose of not only finding much more local optimal results but also analyzing which discipline that the variables according to could be benefit for the convergence and robustness.Response surface method and Monte Carlo simulations were used to analyze whether the objective function and constraint function are sensitive to the variation of variables or not.Then the robust results could be found among a group of different local optimal solutions. 展开更多
关键词 hollow fan blade structural optimization sequential quadratic algorithm finite element method Monte Carlo simulations
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Automatic differentiation for reduced sequential quadratic programming
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作者 Liao Liangcai Li Jin Tan Yuejin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期57-62,共6页
In order to slove the large-scale nonlinear programming (NLP) problems efficiently, an efficient optimization algorithm based on reduced sequential quadratic programming (rSQP) and automatic differentiation (AD)... In order to slove the large-scale nonlinear programming (NLP) problems efficiently, an efficient optimization algorithm based on reduced sequential quadratic programming (rSQP) and automatic differentiation (AD) is presented in this paper. With the characteristics of sparseness, relatively low degrees of freedom and equality constraints utilized, the nonlinear programming problem is solved by improved rSQP solver. In the solving process, AD technology is used to obtain accurate gradient information. The numerical results show that the combined algorithm, which is suitable for large-scale process optimization problems, can calculate more efficiently than rSQP itself. 展开更多
关键词 Automatic differentiation Reduced sequential quadratic programming Optimization algorithm
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SEQUENTIAL QUADRATIC PROGRAMMING METHODS FOR OPTIMAL CONTROL PROBLEMS WITH STATE CONSTRAINTS
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作者 徐成贤 Jong de J. L. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1993年第2期163-174,共12页
A kind of direct methods is presented for the solution of optimal control problems with state constraints. These methods are sequential quadratic programming methods. At every iteration a quadratic programming which i... A kind of direct methods is presented for the solution of optimal control problems with state constraints. These methods are sequential quadratic programming methods. At every iteration a quadratic programming which is obtained by quadratic approximation to Lagrangian function and linear approximations to constraints is solved to get a search direction for a merit function. The merit function is formulated by augmenting the Lagrangian function with a penalty term. A line search is carried out along the search direction to determine a step length such that the merit function is decreased. The methods presented in this paper include continuous sequential quadratic programming methods and discreate sequential quadratic programming methods. 展开更多
关键词 Optimal Control Problems with State Constraints sequential quadratic Programming Lagrangian Function. Merit Function Line Search.
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A SUPERLINEARLY CONVERGENT SPLITTING FEASIBLE SEQUENTIAL QUADRATIC OPTIMIZATION METHOD FOR TWO-BLOCK LARGE-SCALE SMOOTH OPTIMIZATION
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作者 简金宝 张晨 刘鹏杰 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期1-24,共24页
This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method fo... This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method for the discussed problem is proposed.First,we consider the problem of quadratic optimal(QO)approximation associated with the current feasible iteration point,and we split the QO into two small-scale QOs which can be solved in parallel.Second,a feasible descent direction for the problem is obtained and a new SQO-type method is proposed,namely,splitting feasible SQO(SF-SQO)method.Moreover,under suitable conditions,we analyse the global convergence,strong convergence and rate of superlinear convergence of the SF-SQO method.Finally,preliminary numerical experiments regarding the economic dispatch of a power system are carried out,and these show that the SF-SQO method is promising. 展开更多
关键词 large scale optimization two-block smooth optimization splitting method feasible sequential quadratic optimization method superlinear convergence
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An Overview of Sequential Approximation in Topology Optimization of Continuum Structure 被引量:1
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作者 Kai Long Ayesha Saeed +6 位作者 Jinhua Zhang Yara Diaeldin Feiyu Lu Tao Tao Yuhua Li Pengwen Sun Jinshun Yan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期43-67,共25页
This paper offers an extensive overview of the utilization of sequential approximate optimization approaches in the context of numerically simulated large-scale continuum structures.These structures,commonly encounter... This paper offers an extensive overview of the utilization of sequential approximate optimization approaches in the context of numerically simulated large-scale continuum structures.These structures,commonly encountered in engineering applications,often involve complex objective and constraint functions that cannot be readily expressed as explicit functions of the design variables.As a result,sequential approximation techniques have emerged as the preferred strategy for addressing a wide array of topology optimization challenges.Over the past several decades,topology optimization methods have been advanced remarkably and successfully applied to solve engineering problems incorporating diverse physical backgrounds.In comparison to the large-scale equation solution,sensitivity analysis,graphics post-processing,etc.,the progress of the sequential approximation functions and their corresponding optimizersmake sluggish progress.Researchers,particularly novices,pay special attention to their difficulties with a particular problem.Thus,this paper provides an overview of sequential approximation functions,related literature on topology optimization methods,and their applications.Starting from optimality criteria and sequential linear programming,the other sequential approximate optimizations are introduced by employing Taylor expansion and intervening variables.In addition,recent advancements have led to the emergence of approaches such as Augmented Lagrange,sequential approximate integer,and non-gradient approximation are also introduced.By highlighting real-world applications and case studies,the paper not only demonstrates the practical relevance of these methods but also underscores the need for continued exploration in this area.Furthermore,to provide a comprehensive overview,this paper offers several novel developments that aim to illuminate potential directions for future research. 展开更多
关键词 Topology optimization sequential approximate optimization convex linearization method ofmoving asymptotes sequential quadratic programming
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双向隔离型AC-DC矩阵变换器最小开关损耗控制方法
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作者 梅杨 石仪 张家奇 《电工技术学报》 北大核心 2026年第4期1414-1424,共11页
为了实现双向隔离型AC-DC矩阵变换器(BIMC)的高效运行,该文提出一种最小开关损耗控制方法。基于双线电压调制策略,建立电力电子器件损耗模型,引入基于序列二次规划算法(SQP)的优化方法,以输入功率和移相角范围为限定条件,对开关损耗进... 为了实现双向隔离型AC-DC矩阵变换器(BIMC)的高效运行,该文提出一种最小开关损耗控制方法。基于双线电压调制策略,建立电力电子器件损耗模型,引入基于序列二次规划算法(SQP)的优化方法,以输入功率和移相角范围为限定条件,对开关损耗进行最小化寻优,实时计算最优的移相角组合,并应用于变换器的调制过程,以保证变换器的开关损耗最小。仿真和实验结果表明,采用所提出的控制方法可实现网侧电流为正弦电流,功率因数接近于1,直流侧电压与电流稳定,电流纹波率小于1%,且在较宽功率范围内,变换器效率均维持在94%以上,最高可达到96.89%。相较于传统的控制方法而言,所提方法在宽运行范围中均可以使电力电子器件的损耗最小。 展开更多
关键词 AC-DC矩阵变换器 双线电压调制策略 开关损耗 序列二次规划
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非凸推力可行域下的喷水推进船推力分配方法
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作者 丁江明 慕鹏宁 罗腾 《哈尔滨工程大学学报》 北大核心 2026年第1期228-234,共7页
为在喷水推进船舶矢量控制过程中充分利用推进器的性能,本文对喷水推进器特有的非凸推力可行域下的推力分配进行研究。采用区域分配策略和两步优化结构,先将非凸推力可行域划分为多个凸子域进行约束,以避免推力分配时因非凸约束条件导... 为在喷水推进船舶矢量控制过程中充分利用推进器的性能,本文对喷水推进器特有的非凸推力可行域下的推力分配进行研究。采用区域分配策略和两步优化结构,先将非凸推力可行域划分为多个凸子域进行约束,以避免推力分配时因非凸约束条件导致局部最优解,再进行第1步优化计算,得到各喷水推进器的推力指令;然后根据各喷水推进器推力指令确定各喷水推进器运转参数的变化范围,进行第2步优化计算,得到各喷水推进器运转参数指令,从而实现喷水推进船的矢量控制。以一艘喷水推进单体滑行艇为研究对象,对上述方法进行仿真验证,结果表明,该方法能有效处理非凸约束条件下的推力分配问题。 展开更多
关键词 船舶 喷水推进 矢量控制 单手柄操纵系统 推力分配 非凸优化 区域分配 序列二次规划法
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基于MPC的多目标防撞优化算法
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作者 孙辉 张学东 +2 位作者 孙连蔚 杨凯欣 王蕊 《北京航空航天大学学报》 北大核心 2026年第2期445-452,共8页
为避免飞机滑行时追尾风险并兼顾乘客的舒适性,提出一种基于模型预测控制(MPC)的多目标防撞优化算法。建立向运动学模型,考虑飞机滑行的安全性和乘客的舒适性设计目标函数及约束;以相对速度和间距作为参数,设计变权重函数,将其引入到MPC... 为避免飞机滑行时追尾风险并兼顾乘客的舒适性,提出一种基于模型预测控制(MPC)的多目标防撞优化算法。建立向运动学模型,考虑飞机滑行的安全性和乘客的舒适性设计目标函数及约束;以相对速度和间距作为参数,设计变权重函数,将其引入到MPC中,优化安全性权重,利用序列二次规划(SQP)算法对变权重MPC策略进行求解得到期望加速度,并对变权重MPC的稳定性进行分析。通过仿真实验验证所提算法在典型工况下的防撞效果,实验结果表明:所提算法在实现减速防撞的同时,优化了加速度变化幅度,提高了乘客舒适性。 展开更多
关键词 多目标 防撞 模型预测控制 变权重 序列二次规划
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存零约束优化问题的改进序列二次规划法
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作者 房明磊 盛雨婷 +1 位作者 徐奥 邹伟凡 《应用数学》 北大核心 2026年第1期151-160,共10页
在优化控制中,存零约束优化问题是一类新的约束优化问题.由于其特殊的约束条件很可能在存零约束优化问题的可行点处失效,使得常用的约束规范不满足.因此,提出将特殊约束引入目标函数中,应用序列二次规划算法求解该问题.该算法计算量少,... 在优化控制中,存零约束优化问题是一类新的约束优化问题.由于其特殊的约束条件很可能在存零约束优化问题的可行点处失效,使得常用的约束规范不满足.因此,提出将特殊约束引入目标函数中,应用序列二次规划算法求解该问题.该算法计算量少,收敛速度快,并且证明了新算法生成的序列的极限点是该问题的KKT点.最后通过数值结果表明,序列二次规划方法处理这类问题是可行的. 展开更多
关键词 存零约束 序列二次规划 KKT点 全局收敛
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求解最优控制问题的一类单调时间离散格式
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作者 向清清 陈浩 《应用数学和力学》 北大核心 2026年第2期230-242,共13页
近期,Breitenbach和Borzì构造了一类求解常微分方程最优控制问题的序列二次Hamilton(sequential quadratic Hamiltonian,SQH)方法.他们证明了该迭代方法在连续时间情形下的单调收敛性.然而,该迭代方法在离散时间情形下的收敛性质... 近期,Breitenbach和Borzì构造了一类求解常微分方程最优控制问题的序列二次Hamilton(sequential quadratic Hamiltonian,SQH)方法.他们证明了该迭代方法在连续时间情形下的单调收敛性.然而,该迭代方法在离散时间情形下的收敛性质尚未被解决.该文构造了一类中点时间离散格式,并证明了其能保持SQH迭代的单调收敛性.数值实验验证了该方法的有效性及收敛性. 展开更多
关键词 最优控制问题 序列二次Hamilton方法 单调时间离散格式 收敛性
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超高精度平面度误差的混合优化评定及应用
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作者 谭陆洋 齐天飞 +3 位作者 武智渊 张弘治 贾学志 张雷 《光学精密工程》 北大核心 2026年第3期393-402,共10页
针对传统智能优化算法在评定平面度误差时存在计算精度不足、收敛速度慢等问题,提出一种兼具高精度与高效率的平面度误差评定方法。通过设计一种以序列二次规划(Sequential Quadratic Programming,SQP)算法为主、粒子群优化(Particle Sw... 针对传统智能优化算法在评定平面度误差时存在计算精度不足、收敛速度慢等问题,提出一种兼具高精度与高效率的平面度误差评定方法。通过设计一种以序列二次规划(Sequential Quadratic Programming,SQP)算法为主、粒子群优化(Particle Swarm Optimization,PSO)算法为辅的混合算法(PSO-SQP),以满足自研1200 mm口径非接触式平面度检测仪对评定算法的严格要求。利用PSO算法的全局搜索能力进行初步粗搜索,快速获得一个接近全局最优的解作为SQP算法的优质初始点;针对精搜索阶段,利用自适应步长策略替代传统固定步长,从而在局部搜索中实现快速稳定收敛。实验结果表明,PSO-SQP混合算法对初始点偏差、采样规模及测量噪声具有良好的稳定性,与高精度三坐标测量机相比,评定结果差异小于7 nm。在实际工程应用中,对直径280 mm的平面镜进行评定,平面度评定结果与平面镜面形精度指标相符,验证了其工程实用性。PSO-SQP混合算法具有计算精度高、收敛速度快和稳定性好等优点,特别适用于超高精度、大数据量的平面度检测。 展开更多
关键词 精密测量 平面度误差 序列二次规划 粒子群优化 非接触式平面度检测仪
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Sequential quadratic programming particle swarm optimization for wind power system operations considering emissions 被引量:5
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作者 Yang ZHANG Fang YAO +2 位作者 Herbert Ho-Ching IU Tyrone FERNANDO Kit Po WONG 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2013年第3期231-240,共10页
In this paper,a computation framework for addressing combined economic and emission dispatch(CEED)problem with valve-point effects as well as stochastic wind power considering unit commitment(UC)using a hybrid approac... In this paper,a computation framework for addressing combined economic and emission dispatch(CEED)problem with valve-point effects as well as stochastic wind power considering unit commitment(UC)using a hybrid approach connecting sequential quadratic programming(SQP)and particle swarm optimization(PSO)is proposed.The CEED problem aims to minimize the scheduling cost and greenhouse gases(GHGs)emission cost.Here the GHGs include carbon dioxide(CO_(2)),nitrogen dioxide(NO_(2)),and sulphur oxides(SO_(x)).A dispatch model including both thermal generators and wind farms is developed.The probability of stochastic wind power based on the Weibull distribution is included in the CEED model.The model is tested on a standard system involving six thermal units and two wind farms.A set of numerical case studies are reported.The performance of the hybrid computational method is validated by comparing with other solvers on the test system. 展开更多
关键词 Combined economic and emission dispatch Unit commitment Particle swarm optimization sequential quadratic programming Weibull distribution Wind power
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Sequential quadratic programming enhanced backtracking search algorithm 被引量:1
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作者 Wenting ZHAO Lijin WANG +2 位作者 Yilong YIN Bingqing WANG Yuchun TANG 《Frontiers of Computer Science》 SCIE EI CSCD 2018年第2期316-330,共15页
In this paper, we propose a new hybrid method called SQPBSA which combines backtracking search optimization algorithm (BSA) and sequential quadratic programming (SQP). BSA, as an exploration search engine, gives a... In this paper, we propose a new hybrid method called SQPBSA which combines backtracking search optimization algorithm (BSA) and sequential quadratic programming (SQP). BSA, as an exploration search engine, gives a good direction to the global optimal region, while SQP is used as a local search technique to exploit the optimal solution. The experiments are carried on two suits of 28 functions proposed in the CEC-2013 competitions to verify the performance of SQPBSA. The results indicate the proposed method is effective and competitive. 展开更多
关键词 numerical optimization backtracking search algorithm sequential quadratic programming local search
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Maximum likelihood estimation of nonlinear mixed-effects models with crossed random effects by combining first-order conditional linearization and sequential quadratic programming
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作者 Liyong Fu Mingliang Wang +2 位作者 Zuoheng Wang Xinyu Song Shouzheng Tang 《International Journal of Biomathematics》 SCIE 2019年第5期1-18,共18页
Nonlinear mixed-eirects (NLME) modek have become popular in various disciplines over the past several decades.However,the existing methods for parameter estimation imple-mented in standard statistical packages such as... Nonlinear mixed-eirects (NLME) modek have become popular in various disciplines over the past several decades.However,the existing methods for parameter estimation imple-mented in standard statistical packages such as SAS and R/S-Plus are generally limited k) single-or multi-level NLME models that only allow nested random effects and are unable to cope with crossed random effects within the framework of NLME modeling.In t his study,wc propose a general formulation of NLME models that can accommodate both nested and crassed random effects,and then develop a computational algorit hm for parameter estimation based on normal assumptions.The maximum likelihood estimation is carried out using the first-order conditional expansion (FOCE) for NLME model linearization and sequential quadratic programming (SCJP) for computational optimization while ensuring positive-definiteness of the estimated variance-covariance matrices of both random effects and error terms.The FOCE-SQP algorithm is evaluated using the height and diameter data measured on trees from Korean larch (L.olgeiisis var,Chang-paienA.b) experimental plots aa well as simulation studies.We show that the FOCE-SQP method converges fast with high accuracy.Applications of the general formulation of NLME models are illustrated with an analysis of the Korean larch data. 展开更多
关键词 CROSSED RANDOM EFFECTS FIRST-ORDER CONDITIONAL expansion nested RANDOM EFFECTS NONLINEAR mixed-effects models sequential quadratic programming
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受控交通农业模式机器人化作业平台路径规划方法 被引量:1
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作者 闫洪峰 李法镰 +3 位作者 朱玉 李璐 吴海华 方宪法 《农业机械学报》 北大核心 2025年第6期155-166,共12页
针对受控交通农业模式下机器人化作业平台自主作业需求,提出一种对多边形地块具有普适意义的全生产周期作业路径规划方法。该方法构建主永久道网络与子作业路径层双层结构,通过等距缩放与顶点平滑规划转向预留区路径,基于垂直行进方向... 针对受控交通农业模式下机器人化作业平台自主作业需求,提出一种对多边形地块具有普适意义的全生产周期作业路径规划方法。该方法构建主永久道网络与子作业路径层双层结构,通过等距缩放与顶点平滑规划转向预留区路径,基于垂直行进方向投影长度最小化原则确定中心作业区行方向;对主永久道网络设计间隔梭行的遍历顺序,对子作业路径层设计相邻梭行遍历顺序;采用Dubins曲线设计衔接路径,并设计潜在弹性出入口以解决作业弹性中断路径衔接问题;利用序列二次规划算法求解满足运动学约束的路径,消除传统直线-圆弧路径的曲率突变缺陷。综合考虑作业路径占比、作业覆盖率、曲率变化率、路径跃度、压实区域面积占比等指标,以机器人化作业平台为对象进行田间路径规划试验,结果表明,针对凸/凹多边形地块中,主永久道作业路径长度占比达77.21%,子作业层作业路径占比56.87%;作业覆盖面积占比均达90.65%;最大曲率变化率不大于0.04 m^(-2),跃度不大于0.05 m^(-3);总压实区域占比8.83%,将全生产周期作业路径限制在永久固定道上,满足受控交通农业下机器人化作业平台作业需求。 展开更多
关键词 受控交通农业 机器人化作业平台 全生产周期路径规划 运动学约束 序列二次规划
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大跨度斜拱曲梁桥施工监控关键技术研究 被引量:2
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作者 徐郁峰 张展涛 +1 位作者 谢云飞 李子辉 《中外公路》 2025年第3期121-129,共9页
斜拱曲梁桥作为一种拱肋倾斜且主梁呈曲线的新型桥梁结构,因其构造复杂性与显著的空间效应,其施工监控技术与常规桥型相比存在明显差异。为探究此类桥梁施工监控的关键技术,该文以某大跨度斜拱曲梁桥为工程背景,从桥梁的施工过程仿真分... 斜拱曲梁桥作为一种拱肋倾斜且主梁呈曲线的新型桥梁结构,因其构造复杂性与显著的空间效应,其施工监控技术与常规桥型相比存在明显差异。为探究此类桥梁施工监控的关键技术,该文以某大跨度斜拱曲梁桥为工程背景,从桥梁的施工过程仿真分析、现场监测、参数识别及调整等方面展开研究。通过对比板壳单元模型与杆系模型发现,板壳单元模型不仅具有更高的计算精度,还能全面反映斜拱曲梁桥的各向受力情况;同时,针对索力调整中传统影响矩阵法的局限性,提出了一种结合序列二次规划优化的改进方法,有效解决了索力优化不适用的问题。该研究成果可为同类桥梁的施工监控提供理论参考与技术支撑。 展开更多
关键词 斜拱曲梁 施工监控 板壳单元模型 序列二次规划 索力调整
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基于参变量变分原理的纳米孪晶结构的各向异性Cosserat理论建模
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作者 朱宝 孙豪 刘玥 《计算力学学报》 北大核心 2025年第2期196-204,共9页
纳米孪晶结构金属不仅得到实验证明具有优异的强度,而且具有良好的延展性,是改善金属强度-塑韧性倒置关系的重要途径,体现出巨大的工程应用价值。本文基于参变量变分原理,发展了三维各向异性Cosserat弹塑性分析的参数二次规划算法,并且... 纳米孪晶结构金属不仅得到实验证明具有优异的强度,而且具有良好的延展性,是改善金属强度-塑韧性倒置关系的重要途径,体现出巨大的工程应用价值。本文基于参变量变分原理,发展了三维各向异性Cosserat弹塑性分析的参数二次规划算法,并且将该算法应用于纳米孪晶铜的数值建模模拟。通过引入孪晶与基体之间的特殊取向关系,建立了纳米孪晶铜的各向异性Cosserat连续介质模型。考虑到晶体取向不同而产生的各向异性效应以及孪晶与基体之间的不均匀变形产生的应变梯度效应,得到的模型结果与不同实验研究所得的纳米孪晶铜的应力-应变曲线吻合良好。基于该模型,系统地研究了平均孪晶厚度对纳米孪晶铜屈服强度、弹性模量等力学性能的影响。结果表明,各向异性效应主要影响弹性模量和屈服强度,应变梯度效应影响屈服强度和应变硬化率。 展开更多
关键词 参数量变分原理 各向异性 COSSERAT 二次规划算法 纳米孪晶铜
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多约束条件下移动机械手基座位置布局研究
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作者 杨亚莉 窦忠宇 《机械设计与制造》 北大核心 2025年第4期325-330,共6页
移动机械手具有良好的机动性和灵活性,在大型复杂零件的加工中具有广阔的应用前景。为了充分利用机器人的加工能力,设计了移动机械手加工过程中的基座位置布局。首先根据六自由度机械手的运动姿态,考虑了机械手工作过程中的关节角度以... 移动机械手具有良好的机动性和灵活性,在大型复杂零件的加工中具有广阔的应用前景。为了充分利用机器人的加工能力,设计了移动机械手加工过程中的基座位置布局。首先根据六自由度机械手的运动姿态,考虑了机械手工作过程中的关节角度以及奇异性问题,在此基础上建立了相应的运动和刚度评价指标,分析了机械手在多约束条件下的运动特性。为寻找模型的最优解,采用了序列二次规划(SQP)方法进行了模型求解。最后为验证模型和算法的有效性,通过实验对所提六自由度机械的基座位置优化方法进行了验证。 展开更多
关键词 六自由度机械手 多约束 基座布局 运动特能 序列二次规划
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先导式直动电磁阀电磁特性分析及优化研究
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作者 赵世田 谢文庆 +3 位作者 卢倩 蔡晓幸 顾金彤 刘浩宇 《机电工程》 北大核心 2025年第12期2292-2302,共11页
先导式直动电磁阀是船舶设备消防控制系统中的核心组件,先导式直动电磁阀的电磁特性劣化,会导致其动态响应性能的下降,进而导致船舶系统性能和可靠性严重降低,为了解决这一问题,对其磁力特性与动态响应性能进行了多参数协同优化研究。首... 先导式直动电磁阀是船舶设备消防控制系统中的核心组件,先导式直动电磁阀的电磁特性劣化,会导致其动态响应性能的下降,进而导致船舶系统性能和可靠性严重降低,为了解决这一问题,对其磁力特性与动态响应性能进行了多参数协同优化研究。首先,基于ANSYS Maxwell电磁场仿真平台,构建了三维瞬态数值模型,并通过实验验证了模型的准确性,采用系统量化的方式,研究了磁路材料、衔铁锥角、导磁壳厚度、线圈匝数、弹簧预紧力等关键结构参数对磁力特性的影响规律;然后,基于ISIGHT结合最优拉丁超立方实验设计,构建了包含76组样本的数值实验矩阵,结合二阶多项式响应面法,建立了结构参数与开启、关闭响应时间的非线性代理模型;最后,构建了以动态响应时间最短为目标的多目标优化模型,采用非线性序列二次规划算法(NLPQLP)进行了参数寻优,并利用建立的响应面模型对仿真模型计算结果进行了验证。研究结果表明:开启与关闭响应时间代理模型的决定系数R^(2)分别达到0.962和0.929;经优化设计后,电磁阀开启响应时间和关闭响应时间分别降低了8.18%、10.83%。该研究可以为高动态响应电磁阀的工程化设计提供理论依据与技术支撑。 展开更多
关键词 先导式直动电磁阀 磁力特性 响应时间 ISIGHT 二阶多项式响应面 非线性序列二次规划算法 结构参数多目标优化
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