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A Localized Inter-Actuator Network Topology Repair Scheme for Wireless Sensor and Actuator Networks 预览
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作者 Yong Feng Hai Liu +1 位作者 Jie Yang Xiaodong Fu 《中国通信:英文版》 SCIE CSCD 2019年第2期215-232,共18页
Node failure is one of the most severe problems that wireless sensor and actuator networks(WSANs)have to deal with.The failure of actuator nodes,in particular,may result in substantial consequences such as network par... Node failure is one of the most severe problems that wireless sensor and actuator networks(WSANs)have to deal with.The failure of actuator nodes,in particular,may result in substantial consequences such as network partitioning,incorrect and incomplete decision execution for WSANs.This paper proposes an efficient localized scheme,called LANTR,to repair the damaged topology of inter-actuator network while single actuator node paralyzes.For the failure of an ordinary actuator node,LANTR can rapidly repair the topology through relocating only one-hop neighbors of the failure node,meanwhile,keep the original topology structure as much as possible.Given the magnitude of cut vertex actuators playing on the connectivity,LANTR designs a novel method for each cut vertex to select out a specific guardian node with the minimum degree or minimum cumulative degree from its neighbors,which can reduce the repair influence on the original topology and effectively reduce the coverage loss rate.The performance of the proposed scheme is evaluated and compared with several existing representative topology repair schemes,and the results indicate that LANTR can more effectively and efficiently repair the topology of inter-actuator networks. 展开更多
关键词 wireless sensor and ACTUATOR NETWORKS inter-actuator NETWORKS topology REPAIR COVERAGE loss rate
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14T核磁共振成像超导磁体电源拓扑设计及纹波抑制 预览
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作者 彭程伟 高格 +1 位作者 盛志才 周宇 《核聚变与等离子体物理》 CAS CSCD 北大核心 2019年第2期144-150,共7页
根据14T 核磁共振成像(MRI)大电感超导体磁体(电感307H、连接阻抗2mΩ)负载纹波的需求(低压为3V、电流为1500A、电流纹波小于1ppm),基于常见拓扑结构出现的问题,提出了一种适用于这种大电感超导磁体运行电源的拓扑结构。此拓扑结构采用... 根据14T 核磁共振成像(MRI)大电感超导体磁体(电感307H、连接阻抗2mΩ)负载纹波的需求(低压为3V、电流为1500A、电流纹波小于1ppm),基于常见拓扑结构出现的问题,提出了一种适用于这种大电感超导磁体运行电源的拓扑结构。此拓扑结构采用多级处理、无源滤波和有源滤波相结合的思想来设计。介绍了电源的输入级、中间变换级及输出级三个部分的拓扑,并阐述了各部分拓扑设计对负载电流纹波抑制的作用。通过 Matlab 仿真分析,验证了拓扑设计的合理性。 展开更多
关键词 磁体电源 纹波抑制 拓扑结构 核磁共振成像
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一种无变压器型并联混合有源电力滤波器研究 预览
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作者 张淼 庞卓标 +2 位作者 郝雪冬 谢斯炜 张兴旺 《广东工业大学学报》 CAS 2019年第5期33-37,共5页
针对某些场合特定次谐波含量严重超标、无功不足的问题,提出了一种新型无变压器型并联混合有源电力滤波器拓扑结构.该拓扑由有源部分与无源部分组成,在无源部分实现无功补偿的基础上,利用有源部分补偿谐波.同时,系统利用无源部分串联分... 针对某些场合特定次谐波含量严重超标、无功不足的问题,提出了一种新型无变压器型并联混合有源电力滤波器拓扑结构.该拓扑由有源部分与无源部分组成,在无源部分实现无功补偿的基础上,利用有源部分补偿谐波.同时,系统利用无源部分串联分压和串联谐振,大大降低了有源部分工作电压,进而减小有源部分的容量.通过分析该新型拓扑电路的工作特点,建立系统的数学模型,采用解耦控制方法实现对系统的有效控制.实验结果验证了方案的可行性. 展开更多
关键词 混合有源滤波器 无变压器型 特定次谐波 拓扑结构
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基于Visio的拓扑运算在电工仿真中的运用 预览
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作者 刘平 《计算机时代》 2019年第2期43-45,49共4页
提出将电路图描述为等电位点构成的群落及其相互关系的抽象模型的方法,并据此重点探讨在电工教学仿真的特定环境下,通过在矢量绘图软件Visio的后台进行二次开发,来实现电路图上等电位点的搜索的方法。进而通过模型对比的方式,从功能层... 提出将电路图描述为等电位点构成的群落及其相互关系的抽象模型的方法,并据此重点探讨在电工教学仿真的特定环境下,通过在矢量绘图软件Visio的后台进行二次开发,来实现电路图上等电位点的搜索的方法。进而通过模型对比的方式,从功能层面判定Visio所作电路图与标准接法的一致性。 展开更多
关键词 VISIO 二次开发 电工教学仿真 拓扑 等电位群
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“拓扑学”探源 预览
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作者 黄河清 《中国科技术语》 2019年第2期68-71,共4页
拓扑学(topology)是数学中的一个学科。这个学科曾经叫作“形势几何学”,这个名称是数学家江泽涵创制的,但它使用的时间不长。后来topology翻译成了“拓扑学”。“拓扑学”是一个音意兼译词,它的产生应该在20世纪40年代。
关键词 形势几何学 拓扑学 名词 音译
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一种基于作业流的农经权多源数据质量检查方法 预览
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作者 杨秀德 《北京测绘》 2019年第2期216-221,共6页
针对农经权数据类型繁多,检查易出现漏洞的现状,本文提出一种基于作业流过程的数据质量检查方法,该法依据作业流程将农经权数据进行多级分类,并提出质量检查具体指标,评定农经权调查成果质量。以新兴县农经权数据检查为例,实施了基于作... 针对农经权数据类型繁多,检查易出现漏洞的现状,本文提出一种基于作业流过程的数据质量检查方法,该法依据作业流程将农经权数据进行多级分类,并提出质量检查具体指标,评定农经权调查成果质量。以新兴县农经权数据检查为例,实施了基于作业流的质量检查,结果表明提出的方法能够实现农经权数据细小纰漏筛选,完成全面质量检查,具有较强的普适性。同时,该法也为其它类似工程质量检查提供一个新的技术视角。 展开更多
关键词 土地经营承包权 拓扑结构 逻辑一致性 界址点
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多种阻抗网络升压变换器拓扑结构优化研究 预览
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作者 陆灏 武保东 《安徽理工大学学报:自然科学版》 CAS 2019年第4期77-86,共10页
传统Z源升压变换器存在输入电流断续,冲击电流过大,升压能力不足,电容稳态电压过高等问题。对此,国内外学者相继提出了多种改进型阻抗源升压变换器,这些拓扑结构各异,性能有所差别,难以选出较为理想的拓扑结构。通过对目前存在的多种阻... 传统Z源升压变换器存在输入电流断续,冲击电流过大,升压能力不足,电容稳态电压过高等问题。对此,国内外学者相继提出了多种改进型阻抗源升压变换器,这些拓扑结构各异,性能有所差别,难以选出较为理想的拓扑结构。通过对目前存在的多种阻抗网络升压变化器进行简要介绍,对比分析了各种阻抗源拓扑的性能及优缺点,并通过Matlab/Simulink软件进行了仿真波形分析,综合考虑各种阻抗源拓扑性能、成本等优缺点,得出较优拓扑。 展开更多
关键词 阻抗网络 拓扑结构 对比分析
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基于非刚性ICP的三维人脸稠密对应算法
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作者 邓鑫灵 周大可 杨欣 《电子测量技术》 2019年第7期1-6,共6页
三维人脸稠密对应是三维人脸分析研究的前提和基础。目前大多数的稠密对应技术是基于模板形变的方式,非刚性最近点迭代(iterative closest point, ICP)是应用最为广泛的一种,该算法通过逐步形变一个高分辨率的三维人脸模板来逼近目标人... 三维人脸稠密对应是三维人脸分析研究的前提和基础。目前大多数的稠密对应技术是基于模板形变的方式,非刚性最近点迭代(iterative closest point, ICP)是应用最为广泛的一种,该算法通过逐步形变一个高分辨率的三维人脸模板来逼近目标人脸(扫描人脸数据)。但该类方法通过牺牲边缘精度来保持边缘区域的拓扑结构,以保证人脸之间的稠密对应。针对这一问题,提出了一种结合拓扑结构损失项的非刚性ICP算法,使得保持边缘区域拓扑结构的同时不会大幅度牺牲配准精度。实验结果表明,该算法比目前广泛使用的算法配准精度更高。 展开更多
关键词 三维人脸 稠密对应 非刚性最近点迭代 拓扑结构 配准精度
Making the world from topological order
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作者 Philip Ball 《国家科学评论:英文版》 CSCD 2019年第2期227-230,共4页
Topology used to be a term confined to a branch of pure mathematics, where it referred to an invariant property of shape. The classic example was the way objects containing a single hole, like a torus and a coffee cup... Topology used to be a term confined to a branch of pure mathematics, where it referred to an invariant property of shape. The classic example was the way objects containing a single hole, like a torus and a coffee cup with handle, can be smoothly moulded into one another without tearing. But topological considerations have long played a role in the physics of matter, where for example they might dictate particular arrangements of component parts that can't be erased from the system. The classic example here is the fact that a 'hairy ball' can't be combed flat without having at least two pointy tufts. Such 'defects' in organization can be considered "topologically protected', since they are robust against any recombing of the hair. They are universal features that don't depend on the material specifics of the system: topological defects in liquid crystals are analogous to defects in spacetime called cosmic strings. 展开更多
关键词 TOPOLOGY TERM MATHEMATICS
Topology optimization of continuum structures considering damage based on independent continuous mapping method 预览
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作者 Jiazheng Du Yunhang Guo +1 位作者 Zuming Chen Yunkang Sui 《力学学报:英文版》 SCIE EI CAS CSCD 2019年第2期433-444,共12页
A continuum topology optimization usually produces results similar to a skeleton structure. In addition, the material utilization in the optimized structure is greatly improved compared with the original structure. On... A continuum topology optimization usually produces results similar to a skeleton structure. In addition, the material utilization in the optimized structure is greatly improved compared with the original structure. On the other hand, the redundancy of the structure is greatly reduced due to the removed material. A partial local failure in the optimized structure makes it more difficult for the entire structure to meet the strength/stiffness requirements. By using the independent continuous mapping (ICM) method, with minimal weight as the objective and both stress and displacement as the respective constraints, the continuum topology optimization models can be employed, which also consider damage. A dual-sequence quadratic programming (DSQP) algorithm is used to solve the topology optimization models. Numerical examples confirm the effectiveness and feasibility of the models. The results indicate that both a good load-path and weight reduction can be obtained. In addition, compared with the structure obtained using conventional topology optimization, redundancy is improved greatly, and the strength/stiffness requirements for the structure can be satisfied for each damage scenario. Furthermore, the results indicate that the strength/stiffness of the structure, after topology optimization, is slightly sensitive for local damage. 展开更多
关键词 DAMAGE REDUNDANCY TOPOLOGY optimization ICM method
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提高相依网络鲁棒性的加边策略研究 预览
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作者 陈世明 戴亚明 程运洪 《电子科技大学学报》 EI CAS CSCD 北大核心 2019年第1期103-109,共7页
网络结构对于网络的鲁棒性能具有一定影响。该文针对不同耦合方式的相依网络,研究了网络鲁棒性与加边策略之间的关系。对采用部分耦合和一对一全耦合的相依网络模型,分别提出了低相对介数内加边策略和低相对介数耦合加边策略,并将其与... 网络结构对于网络的鲁棒性能具有一定影响。该文针对不同耦合方式的相依网络,研究了网络鲁棒性与加边策略之间的关系。对采用部分耦合和一对一全耦合的相依网络模型,分别提出了低相对介数内加边策略和低相对介数耦合加边策略,并将其与已有的几种策略进行仿真对比,仿真结果表明了该文所提策略的有效性。此外,进一步探究了负载参数对于加边策略的影响。研究发现,随着负载参数的不断增加,采用加边策略后,网络鲁棒性普遍提高,但选取不同的负载参数,可能会导致某一种加边策略无效。因此,综合考虑负载参数、选取适当的加边策略,能够更好地提高网络抵御级联失效的鲁棒性。研究成果对于有效使用资源,优化相依网络的拓扑结构,提高相依网络抵御级联失效的鲁棒性具有一定的指导作用。 展开更多
关键词 加边策略 相依网络 鲁棒性 拓扑结构
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别名解析技术研究进展 预览
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作者 王占丰 程光 +3 位作者 胡超 李晗 翁年凤 曹华平 《通信学报》 EI CSCD 北大核心 2019年第7期169-185,共17页
别名解析是发现位于同一台路由器上不同IP接口的技术,是网络拓扑推断的一个关键步骤,将因特网的逻辑拓扑转换为物理拓扑从而实现虚拟空间与现实世界映射重要方法。首先介绍了IP别名解析的概念,分析了IP别名关系的种类,然后对IPv4和IPv6... 别名解析是发现位于同一台路由器上不同IP接口的技术,是网络拓扑推断的一个关键步骤,将因特网的逻辑拓扑转换为物理拓扑从而实现虚拟空间与现实世界映射重要方法。首先介绍了IP别名解析的概念,分析了IP别名关系的种类,然后对IPv4和IPv6的别名解析算法分别进行了详细论述,最后通过对所有算法的综合分析和对比,指出了在未来的研究中,特别是IPv6别名解析中,在别名目标集合筛选、指纹选择及推断方法中应注意的问题。 展开更多
关键词 网络空间 测量 IP别名解析 拓扑
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FBG宏应变传感器在工程健康监测中的分布 预览
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作者 王维俊 王大鹏 《江苏建筑》 2019年第2期53-54,66共3页
文章主要探讨长标距光纤布拉格光栅(FBG)宏应变传感器在工程健康监测中的几种分布方法,并叙述每种分布方式运用的条件。目前,长标距光纤布拉格光栅(FBG)宏应变传感器布置的方法运用的最广泛的有3种,即简单拓扑结构、平行拓扑结构和交叉... 文章主要探讨长标距光纤布拉格光栅(FBG)宏应变传感器在工程健康监测中的几种分布方法,并叙述每种分布方式运用的条件。目前,长标距光纤布拉格光栅(FBG)宏应变传感器布置的方法运用的最广泛的有3种,即简单拓扑结构、平行拓扑结构和交叉拓扑结构。通过这些拓扑可以测量平均应变、平均曲率、平均切应变、挠度以及裂缝的发展等重要结构数据。 展开更多
关键词 FBG 健康监测 宏应变 拓扑结构 长标距
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某乘用车的转向盘怠速抖动优化 预览
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作者 蔡亚运 杨昌昌 +1 位作者 张瑞乾 陈勇 《北京信息科技大学学报:自然科学版》 2019年第3期53-57,共5页
针对某乘用车在怠速开空调工况下转向盘振动过大的问题,建立有限元模型进行分析,发现转向系统的一阶垂向模态频率与发动机怠速开空调时的二阶激振频率相近。通过有限元分析,确认管梁支架刚度不足以及转向系统与车身连接处刚度不足导致... 针对某乘用车在怠速开空调工况下转向盘振动过大的问题,建立有限元模型进行分析,发现转向系统的一阶垂向模态频率与发动机怠速开空调时的二阶激振频率相近。通过有限元分析,确认管梁支架刚度不足以及转向系统与车身连接处刚度不足导致转向系统模态降低引发共振。在该有限元模型基础上进行优化分析,提高转向系统一阶模态频率,并进行实车测试。最终,转向盘3个方向的振动均降低至0. 5 m/s~2以下,满足要求。 展开更多
关键词 转向盘 怠速 转向系统 模态分析 结构优化 拓扑
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应用于车载充电器的双向DC-DC变换器综述 预览
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作者 蒋超 杜贵平 《电源学报》 CSCD 北大核心 2019年第4期1-9,共9页
在车载充电器的工作环境中,双向DC-DC变换器要满足功率密度大和宽输出电压范围以及体积小和效率高等条件。根据是否存在电气隔离,车载充电器的双向DC-DC变换器拓扑大致可分为非隔离型和隔离型。不同类型的变换器其拓扑结构和控制方法都... 在车载充电器的工作环境中,双向DC-DC变换器要满足功率密度大和宽输出电压范围以及体积小和效率高等条件。根据是否存在电气隔离,车载充电器的双向DC-DC变换器拓扑大致可分为非隔离型和隔离型。不同类型的变换器其拓扑结构和控制方法都不尽相同,相应地有不同的性能表现,同时,宽禁带器件的发展也在提升双向DC-DC变换器性能方面表现出了巨大的潜力。对这些拓扑和控制方法的演变过程进行了详细地分类和总结,对新器件带来的影响进行了综合叙述,同时归纳了目前仍存在的问题,最后提出对其的展望与总结。 展开更多
关键词 车载充电器 双向DC-DC变换器 拓扑结构 控制方法 宽禁带器件
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Concurrent optimization of structural topology and infill properties with a CBF-based level set method
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作者 Long JIANG Yang GUO +3 位作者 Shikui CHEN Peng WEI Na LEI Xianfeng David GU 《机械工程前沿:英文版》 CSCD 2019年第2期171-189,共19页
In this paper,a parametric level-set-based topology optimization framework is proposed to concurrently optimize the structural topology at the macroscale and the effective infill properties at the micro/meso scale.The... In this paper,a parametric level-set-based topology optimization framework is proposed to concurrently optimize the structural topology at the macroscale and the effective infill properties at the micro/meso scale.The concurrent optimization is achieved by a computational framework combining a new parametric level set approach with mathematical programming.Within the proposed framework,both the structural boundary evolution and the effective infill property optimization can be driven by mathematical programming,which is more advantageous compared with the conventional partial differential equatiodriven level set approach.Moreover,the proposed approach will be more efficient in handling nonlinear problems with multiple constraints.Instead of using radial basis functions(RBF),in this paper,we propose to construct a new type of cardinal basis functions(CBF)for the level set function parameterization.The proposed CBF parameterization ensures an explicit impose of the lower and upper bounds of the design variables.This overcomes the intrinsic disadvantage of the conventional RBF-based parametric level set method,where the lower and upper bounds of the design variables oftentimes have to be set by trial and error;A variational distance regularization method is utilized in this research to regularize the level set function to be a desired distanceregularized shape.With the distance information embedded in the level set model,the wrapping boundary layer and the interior infill region can be naturally defined.The isotropic infill achieved via the mesoscale topology optimization is conformally fit into the wrapping boundary layer using the shape-preserving conformal mapping method,which leads to a hierarchical physical structure with optimized overall topology and effective infill properties.The proposed method is expected to provide a timely solution to the increasing demand for multiscale and multifunctional structure design. 展开更多
关键词 CONCURRENT TOPOLOGY OPTIMIZATION PARAMETRIC level set method cardinal basis function shell-infill structure design confonnal mapping
On the Contribution of Wu Wen-Tsün to Algebraic Topology
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作者 BRASSELET Jean-Paul 《系统科学与复杂性学报:英文版》 SCIE EI CSCD 2019年第1期3-36,共34页
The aim of this article is to present the contribution of Wu Wen-Tsün to Algebraic Topology and more precisely to the theory of characteristic classes. Several papers provide complete and welldocumented biography... The aim of this article is to present the contribution of Wu Wen-Tsün to Algebraic Topology and more precisely to the theory of characteristic classes. Several papers provide complete and welldocumented biography and academic career of Wu Wen-Tsün, in particular, Hudecek, 2014;O’Connor and Robertson, 2006;Wen-Tsün Wu’s Academic Career, 2006;Selected works of Wen-Tsun Wu, 2008.The author does not repeat the details provided in these papers concerning the Wu Wen-Tsün’s bibliography, we will just mention people involved in the Wu Wen-Tsün’s period in France.In addition to Wu Wen-Tsün’s papers, the Dieudonné’s book(Dieudonné, 1960) provides an excellent presentation of main results of Wu Wen-Tsün in Algebraic and Differential Topology. The author will use and abuse of this book(and refer to) when suitable.In the introduction, the author recalls mainly historical facts concerning the contribution of Wu Wen-Tsün to Algebraic Topology. The second section shows specifically the contribution of Wu WenTsün to the Stiefel-Whitney classes and introduces the third section, dealing with the(real) Wu classes.The author provides definition, properties as well as further developments and generalizations of the Wu classes. The fourth and fifth sections are devoted to recent applications: In Cobordism theory and in Mathematical Physics. The author notices that Wu classes have been used as well in other domains,in particular surgery theory(Madsen and Milgram, 1979). The last section concerns the complex Wu classes and shows that the more recent Mather classes coincide with the previously defined complex Wu classes, that is a result from Zhou(1994)(see also Liu, 1996).This article is devoted to the contribution of Wu Wen-Tsün to the theory of Characteristic Classes,which coincides with his "French period"(1947–1951). However, speaking of Algebraic Topology, it is worthwhile to mention the important contribution of Wu Wen-Tsün to the Theory of realization of complexes or manifolds in Euclidean spaces and of 展开更多
关键词 ALGEBRAIC TOPOLOGY characteristic CLASS COBORDISM theory mathematical PHYSICS WU CLASS
Topology optimization of piezoelectric bi-material actuators with velocity feedback control
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作者 Mariana MORETTI Emilio C.N.SILVA 《机械工程前沿:英文版》 CSCD 2019年第2期190-200,共11页
In recent years,the new technologies and discoveries on manufacturing materials have encouraged researchers to investigate the appearance of material properties that are not naturally available.Materials featuring a s... In recent years,the new technologies and discoveries on manufacturing materials have encouraged researchers to investigate the appearance of material properties that are not naturally available.Materials featuring a specific stiffness,or structures that combine non-structural and stmctural functions are applied in the aerospace,electronics and medical industry fields.Particularly,structures designed for dynamic actuation with reduced vibration response are the focus of this work.The bi-material and multifunctional concepts are considered for the design of a controlled piezoelectric actuator with vibration suppression by means of the topology optimization method(TOM).The bi-material piezoelectric actuator(BPEA)has its metallic host layer designed by the TOM,which defines the structural function,and the electric function is given by two piezo-ceramic layers that act as a sensor and an actuator coupled with a constant gain active velocity feedback control(AVFC).The AVFC,provided by the piezoelectric layers,affects the structural damping of the system through the velocity state variables readings in time domain.The dynamic equation analyzed throughout the optimization procedure is fully elaborated and implemented.The dynamic response for the rectangular fbur-noded finite element analysis is obtained by the Newmark's time-integration method,which is applied to the physical and the adjoint systems,given that the adjoint formulation is needed for the sensitivity analysis.A gradient-based optimization method is applied to minimize the displacement energy output measured at a predefined degree-of-freedom of the BPEA when a transient mechanical load is applied.Results are obtained for different control gain values to evaluate their influence on the final topology. 展开更多
关键词 TOPOLOGY optimization method BI-MATERIAL piezoactuator active VELOCITY feedback control timedomain transient analysis HOST structure design vibration suppression
Robust topology optimization of hinge-free compliant mechanisms with material uncertainties based on a non-probabilistic field model
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作者 Junjie ZHAN Yangjun LUO 《机械工程前沿:英文版》 CSCD 2019年第2期201-212,共12页
This paper presents a new robust topology optimization framework for hinge-free compliant mechanisms with spatially varying material uncertainties,which are described using a non-probabilistic bounded field model.Boun... This paper presents a new robust topology optimization framework for hinge-free compliant mechanisms with spatially varying material uncertainties,which are described using a non-probabilistic bounded field model.Bounded field uncertainties are efficiently represented by a reduced set of uncertain-but-bouncled coeflficients on the basis of the series expansion method.Robust topology optimization of compliant mechanisms is then defined to minimize the variation in output displacement under constraints of the mean displacement and predefined material volume.The nest optimization problem is solved using a gradient-based optimization algorithm.Numerical examples are presented to illustrate the effectiveness of the proposed method for circumventing hinges in topology optimization of compliant mechanisms. 展开更多
关键词 compliant mechanisms ROBUST topology optimization HINGES uncertainty BOUNDED field
Lightweight Topology Optimization with Buckling and Frequency Constraints Using the Independent Continuous Mapping Method
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作者 Hongling Ye Yunkang Sui Weiwei Wang 《固体力学学报:英文版》 SCIE EI CSCD 2019年第3期310-325,共16页
This research focuses on the lightweight topology optimization method for structures under the premise of meeting the requirements of stability and vibration characteristics. A new topology optimization model with the... This research focuses on the lightweight topology optimization method for structures under the premise of meeting the requirements of stability and vibration characteristics. A new topology optimization model with the constraints of natural frequencies and critical buckling loads and the objective of minimizing the structural volume is established and solved based on the independent continuous mapping method. The eigenvalue equations and composite exponential filter functions are applied to convert the optimization formulation into a continuous, solvable mathematical programming model. In the process of topology optimization, suitable initial values of the filter functions are chosen to avoid local modes, and the dynamic frequency gap constraints are added in the optimal model to prevent mode switches. Furthermore, for the optimal structures with grey elements obtained by the continuous optimization model, the bisection-inverse iteration is applied to search the optimal discrete structures. Finally, a detailed scheme is given for the buckling and frequency topology optimization problem. Numerical examples illustrate that the modelling method of minimizing the economic index with given performance requirements is practical and feasible for multi-performance topology optimization problems. 展开更多
关键词 TOPOLOGY optimization LIGHTWEIGHT BUCKLING CONSTRAINTS Frequency CONSTRAINTS ICM method
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