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ON THE EXACT HAUSDORFF MEASURE OF A CLASS OF SELF-SIMILAR SETS SATISFYING OPEN SET CONDITION 被引量:2
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作者 Shaoyuan Xu Weiyi Su Zuoling Zhou 《Analysis in Theory and Applications》 2008年第1期93-100,共8页
In this paper, we provide a new effective method for computing the exact value of Hausdorff measures of a class of self-similar sets satisfying the open set condition (OSC). As applications, we discuss a self-simila... In this paper, we provide a new effective method for computing the exact value of Hausdorff measures of a class of self-similar sets satisfying the open set condition (OSC). As applications, we discuss a self-similar Cantor set satisfying OSC and give a simple method for computing its exact Hausdorff measure. 展开更多
关键词 self-similar set Hausdorff measure and Hausdorff dimension open set condition
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On <i>M</i>-Asymmetric Semi-Open Sets and Semicontinuous Multifunctions in Bitopological Spaces 被引量:2
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作者 Levy K. Matindih Edwin Moyo 《Advances in Pure Mathematics》 2021年第4期218-236,共19页
The purpose of this paper is to introduce the notions of m-asymmetric semiopen sets and M-asymmetric semicontinuous multifunctions defined between asymmetric sets satisfying certain minimal conditions in the framework... The purpose of this paper is to introduce the notions of m-asymmetric semiopen sets and M-asymmetric semicontinuous multifunctions defined between asymmetric sets satisfying certain minimal conditions in the framework of bitopological spaces. Some new characterizations of m-asymmetric semiopen sets and M-asymmetric semicontinuous multifunctions will be investigated and several fundamental properties will be obtained. 展开更多
关键词 m-Spaces m-Semiasymmetric open and Closed sets Upper and Lower M-Asymmetric Semicontinuous Multifunction
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γ-(α,β)-Open Sets and γ-(α,β)-Ti Spaces 被引量:1
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作者 WU Yao-qiang 《Chinese Quarterly Journal of Mathematics》 2018年第3期324-330,共7页
We introduce the concept of γ-(α, β)-open sets and the concepts of γ-(α, β)-T_i spaces(i = 0, 1, 2, 3, 4) based on the concept of(α, β)-open sets. We obtain some properties of γ-(α, β)-Tispaces. Furthermore... We introduce the concept of γ-(α, β)-open sets and the concepts of γ-(α, β)-T_i spaces(i = 0, 1, 2, 3, 4) based on the concept of(α, β)-open sets. We obtain some properties of γ-(α, β)-Tispaces. Furthermore, we study their essential characterization in topological space. 展开更多
关键词 γ-open setS β)-open setS γ-(α β)-open setS γ-(α β)-Tispaces
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G-Kernel-Open Sets, G-Kernel-Neighborhoods and G-Kernel-Derived Sets 被引量:2
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作者 Li LIU 《Journal of Mathematical Research with Applications》 CSCD 2018年第3期276-286,共11页
Based on G-hulls and G-kernels under the meaning of G-methods on sets, we introduce the concepts of G-hull-closed sets, G-kernel-open sets, G-kernel-neighborhoods and G-kernel-derived sets, discuss some related proper... Based on G-hulls and G-kernels under the meaning of G-methods on sets, we introduce the concepts of G-hull-closed sets, G-kernel-open sets, G-kernel-neighborhoods and G-kernel-derived sets, discuss some related properties. In particular, we define pointwise G-methods, prove the consistency of G-closed sets and G-hull-closed sets, G-open sets and Gkernel-open sets, G-neighborhoods and G-kernel-neighborhoods, G-derived sets and G-kernelderived sets under this method, and enrich some results about G-closed sets, G-open sets,G-interiors, G-neighborhoods and G-derived sets in sets. At the same time, we put forward some problems for further research. 展开更多
关键词 topological spaces G-methods pointwise G-methods G-hull-closed sets G-kernel-open sets G-kernel-neighborhoods G-kernel-derived sets
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基于OpenGAN的射频指纹开集识别研究 被引量:1
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作者 高敏 陈志伟 +2 位作者 文红 侯文静 侯欣宇 《通信技术》 2025年第2期189-195,共7页
射频指纹作为设备识别的新兴手段,在设备认证等领域具有巨大潜力,但伪装设备模仿射频特征威胁网络安全,未知设备识别因此成为关键。提出了基于OpenGAN的射频指纹开集识别方法,引入重构损失与聚类损失优化生成对抗网络特征分布,提升识别... 射频指纹作为设备识别的新兴手段,在设备认证等领域具有巨大潜力,但伪装设备模仿射频特征威胁网络安全,未知设备识别因此成为关键。提出了基于OpenGAN的射频指纹开集识别方法,引入重构损失与聚类损失优化生成对抗网络特征分布,提升识别精度与鲁棒性。实验表明,OpenGAN在不同信噪比下优于传统OpenMAX方法,尤其在高开放度与低信噪比条件下表现更佳。该方法为射频指纹开集识别与无线网络安全提供了新思路和重要参考。 展开更多
关键词 射频指纹 开集识别 openGAN算法 重构损失 聚类损失
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Spatial Distribution Feature Extraction Network for Open Set Recognition of Electromagnetic Signal
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作者 Hui Zhang Huaji Zhou +1 位作者 Li Wang Feng Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期279-296,共18页
This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open environment.The spatial distri... This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open environment.The spatial distribution feature extraction layer in SDFEN replaces convolutional output neural networks with the spatial distribution features that focus more on inter-sample information by incorporating class center vectors.The designed hybrid loss function considers both intra-class distance and inter-class distance,thereby enhancing the similarity among samples of the same class and increasing the dissimilarity between samples of different classes during training.Consequently,this method allows unknown classes to occupy a larger space in the feature space.This reduces the possibility of overlap with known class samples and makes the boundaries between known and unknown samples more distinct.Additionally,the feature comparator threshold can be used to reject unknown samples.For signal open set recognition,seven methods,including the proposed method,are applied to two kinds of electromagnetic signal data:modulation signal and real-world emitter.The experimental results demonstrate that the proposed method outperforms the other six methods overall in a simulated open environment.Specifically,compared to the state-of-the-art Openmax method,the novel method achieves up to 8.87%and 5.25%higher micro-F-measures,respectively. 展开更多
关键词 Electromagnetic signal recognition deep learning feature extraction open set recognition
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Exclusive Fibula Osteosynthesis for Treating Open Fractures Gustillo I-III B of the Distal Half of the Leg Bones in a Resources-Limited Setting
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作者 Georges Kuyigwa Toha Paul Munguakonkwa Budema +2 位作者 Ona Longombe Ahuka Akinja Bitum Uwonda Jean Marie Vianney Kabangu Tshimbila 《Open Journal of Orthopedics》 2023年第3期108-121,共22页
Introduction: Management of open leg bones fractures is a challenging health issue for the surgeon, particularly true in resource-limited settings. In this study, we evaluate exclusive fibular osteosynthesis in the tr... Introduction: Management of open leg bones fractures is a challenging health issue for the surgeon, particularly true in resource-limited settings. In this study, we evaluate exclusive fibular osteosynthesis in the treatment of open fractures of the distal half of the leg bones as a therapeutic option in our context. Methods: This is a prospective, experimental, multicenter study of 30 open fractures of the distal half of the leg bones treated with exclusive fibula osteosynthesis, conducted in 3 hospitals in the DRC from January 1, 2013 to September 30, 2016. Results: The age range of 20 to 40 years grouped 22 (73.4%) patients, the sex ratio was 1:1 and the unemployed were the most involved with 16 (53.3%) cases. The Gustilo II, I, III B and III A types represented 40%, 33.3%, 20% and 6.7%, respectively. The fractures were located in the distal third in 12 (40%) cases, in the middle third in 11 (36.7%) cases, and in both malleoli in 7 cases (23.3%). Osteosynthesis of the fibula by screw plate was applied in 22 (73.3%) patients and pinning in 8 (26.7%). Satisfactory reduction of the tibial fracture site was achieved in 29 (96.7%) cases and 100% bone healing was achieved within an average of 10 weeks. Four (13.3%) loss of alignment, 1 (3.3%) infection, 1 (3.3%) skin necrosis and 2 (6.7%) ankle stiffness complicated our fractures. Conclusion: Exclusive osteosynthesis of the fibula as a common technique for fractures of the distal half of the leg bones allowed us to reduce, immobilize and consolidate the tibial fracture in the required time and to preserve the mobility of the ankle. 展开更多
关键词 Fibular Exclusive Osteosynthesis open Tibial Fractures Resources Limited settings Tibial Fracture Consolidation
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Robust Set Stabilization and Its Instances for Open Quantum Systems
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作者 Ming Zhang Zairong Xi Tzyh-Jong Tarn 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第9期5-9,共5页
We propose and discuss a novel concept of robust set stabilization by permissible controls; this concept is helpful when dealing with both a priori information of model parameters and different permissible controls in... We propose and discuss a novel concept of robust set stabilization by permissible controls; this concept is helpful when dealing with both a priori information of model parameters and different permissible controls including quantum measurements. Both controllability and stabilization can be regarded as the special case of the novel concept. An instance is presented for a kind of uncertain open quantum systems to further justify this gen- eralized concept. It is underlined that a new type of hybrid control based on periodically perturbed projective measurements can be the permissible control of uncertain open quantum systems when perturbed projective measurements are available. The sufficient conditions are given for the robust set stabilization of uncertain quantum open systems by the hybrid control, and the design of the hybrid control is reduced to selecting the period of measurements. 展开更多
关键词 Robust set Stabilization and Its Instances for open Quantum Systems
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Weak Form of Fuzzy Open Sets and Their Related Continuity
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作者 N. Gowrisankar N. Rajesh 《模糊系统与数学》 CSCD 北大核心 2010年第3期86-91,共6页
The aim of this paper is to give a new class of fuzzy open sets called fuzzy pre-γ-open sets in fuzzy topological spaces. Also,a new type of fuzzy continuous functions called,fuzzy pre-γ-continuous functions is intr... The aim of this paper is to give a new class of fuzzy open sets called fuzzy pre-γ-open sets in fuzzy topological spaces. Also,a new type of fuzzy continuous functions called,fuzzy pre-γ-continuous functions is introduced and studied. 展开更多
关键词 模糊理论 空间理论 计算方法 数学理论
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Distributed Saturated Impulsive Quasi-Consensus for Leader-Follower Multi-Agent Systems:An Open Topology Framework
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作者 Haitao Zhu Jianquan Lu +1 位作者 Yijun Lou Xinsong Yang 《IEEE/CAA Journal of Automatica Sinica》 2025年第9期1941-1943,共3页
Dear Editor,This letter studies a real-world issue in leader-follower multi-agent systems(MASs)named open topology,which permits the variations of agent set and network connections.Specially,a novel transition process... Dear Editor,This letter studies a real-world issue in leader-follower multi-agent systems(MASs)named open topology,which permits the variations of agent set and network connections.Specially,a novel transition process is developed to explain how the involved variation of network scale affects the dynamic behavior of the MASs.From a resource limited perspective,the distributed saturated impulsive control is then designed,under which some sufficient criteria are integrated into local quasi-consensus performance.We also provide a combined optimization algorithm for all agents to make the estimated domain of initial errors closer to the real one,thereby resulting in less conservativeness.Finally,a numerical example validates our results. 展开更多
关键词 distributed saturated impulsive control leader follower multi agent systems optimization algorithm agent set network open topology transition process open topologywhich quasi consensus
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基于改进OpenMax的开集干扰识别方法
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作者 刘佳楠 宋志群 李勇 《计算机测量与控制》 2025年第5期306-312,321,共8页
目前的无线通信干扰识别研究主要针对闭集场景,为了面对日益复杂的电磁环境,对无线通信开集场景下未知干扰信号识别问题进行了研究,提出了一种基于改进OpenMax的开集干扰识别算法;该算法通过将干扰信号从时频空间映射至特征空间进行聚类... 目前的无线通信干扰识别研究主要针对闭集场景,为了面对日益复杂的电磁环境,对无线通信开集场景下未知干扰信号识别问题进行了研究,提出了一种基于改进OpenMax的开集干扰识别算法;该算法通过将干扰信号从时频空间映射至特征空间进行聚类,并采用基于距离的损失函数进行网络训练;通过计算样本映射至特征空间的点与中心锚点之间的欧几里得距离,判断信号属于已知干扰类别还是未知干扰;引入OpenMax算法对样本边界进行拟合,从而实现对阈值的自适应调节;实验结果表明,该算法对干扰信号的聚类效果优秀,可以在对已知干扰识别准确率超过90%的同时识别出未知干扰,更加适合动态环境下的干扰识别。 展开更多
关键词 干扰识别 未知干扰信号 开集识别 深度学习 度量学习
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Level set函数快速步进并行重构的分区优化 被引量:1
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作者 夏波 黄筱云 +2 位作者 陈同庆 程永舟 江诗群 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2019年第9期1601-1607,共7页
为进一步提升Level set函数重构的分区并行重构效率,本文采用均分交界面方式进行分区,并保证生成内边界重构节点数量最少。通过运用基于共享存储并行编程(OpenMP)多线程技术的并行计算模型,实现圆球、Zalesak球和哑铃等值面的并行重构... 为进一步提升Level set函数重构的分区并行重构效率,本文采用均分交界面方式进行分区,并保证生成内边界重构节点数量最少。通过运用基于共享存储并行编程(OpenMP)多线程技术的并行计算模型,实现圆球、Zalesak球和哑铃等值面的并行重构。计算结果表明:新分区方法能平衡子区域间计算荷载,减少子区域间信息传递次数和节点回滚次数,与均分区域方法相比,新分区方法能够获得更高计算速度,具有更好的实用性和可扩展性。 展开更多
关键词 LEVEL set函数 快速步进法 并行重构 分区优化 交界面 共享存储并行编程 多线程技术 加速比
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基于过渡桥接机制的对抗性开放集领域自适应
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作者 田青 郁江森 +2 位作者 刘祥 李燕芝 申珺妤 《计算机工程》 北大核心 2026年第1期116-125,共10页
无监督领域自适应(UDA)的目的是将知识从带有标记样本的源域转移到没有标记样本的目标域,其假设源域和目标域具有相同的类别,但这一假设在现实世界场景下往往难以成立。目标域通常包含着源域未被发现的新类别样本,这种设置称为开放集领... 无监督领域自适应(UDA)的目的是将知识从带有标记样本的源域转移到没有标记样本的目标域,其假设源域和目标域具有相同的类别,但这一假设在现实世界场景下往往难以成立。目标域通常包含着源域未被发现的新类别样本,这种设置称为开放集领域自适应(OSDA)。在OSDA中,丰富的域特定特征使得学习域不变表示面临着巨大挑战。现有的OSDA方法往往忽略了域特定特征,并将域差异直接进行最小化,这可能导致类别之间的边界不清晰并削弱模型的泛化能力。为了解决这一问题,提出一种基于过渡桥接机制的OSDA方法(OSTBM)。在特征提取器和域鉴别器上建立过渡桥接机制,以减少域特定特征在整体传递过程中的干扰,并提高域鉴别器的鉴别能力,从而在特征对齐过程中更好地对源分布与目标已知分布进行对齐,并将目标未知分布推离决策边界。实验结果表明,所提方法在多个基准数据集上表现优于现有的OSDA方法,展现了优越的性能。 展开更多
关键词 领域自适应 迁移学习 开放集识别 过渡桥接机制 对抗学习
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基于域对抗神经网络的半监督水声目标识别方法
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作者 杜箫扬 洪峰 《声学学报》 北大核心 2026年第1期145-157,共13页
现有水声目标被动识别方法存在模型跨域泛化能力不足以及对未知目标适应性不足的问题。本文提出一种基于联合训练策略的最大平均差异域对抗网络,将最大均值差异度量融入域对抗训练框架,通过约束域分类器的优化过程实现跨域特征对齐,同时... 现有水声目标被动识别方法存在模型跨域泛化能力不足以及对未知目标适应性不足的问题。本文提出一种基于联合训练策略的最大平均差异域对抗网络,将最大均值差异度量融入域对抗训练框架,通过约束域分类器的优化过程实现跨域特征对齐,同时,通过联合训练机制学习一维频谱与二维梅尔频率倒谱系数特征所包含的信息,并设计包含特征模板构建、动态阈值确定与相似度匹配的三阶段开集识别机制。在DeepShip数据集闭集跨域任务中,算法在半监督条件下可达到73.83%的平均识别准确率,相较于原始域对抗神经网络算法提升约11%。在开集识别场景下,对未知目标的识别准确率达63.44%,较传统方法提升约35%。实验结果表明,所提方法能有效缓解域失配问题,同时可以在有限标注条件下兼顾已知类判别与未知类检测的双重需求。 展开更多
关键词 水声目标识别 半监督学习 域自适应 开集识别
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基于YOLO-OpenMax的水声通信信号开集识别方法 被引量:3
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作者 李杰 李勇斌 +2 位作者 郑娄 王彬 黄焱 《信息工程大学学报》 2024年第3期258-264,271,共8页
水声通信信号调制方式随着技术进步从典型的传统调制方式发展为水声通信机厂商私有开发的新型调制方式,这使得现有的水声通信信号闭集调制识别技术实用性受到制约,但现阶段鲜有研究基于深度学习的水声通信信号调制方式的开集识别方法。... 水声通信信号调制方式随着技术进步从典型的传统调制方式发展为水声通信机厂商私有开发的新型调制方式,这使得现有的水声通信信号闭集调制识别技术实用性受到制约,但现阶段鲜有研究基于深度学习的水声通信信号调制方式的开集识别方法。针对此现状,提出一种基于YOLO图像检测识别网络和OpenMax模型的开集识别方法。利用YOLOv5网络的输出特点,将传统OpenMax模型的处理方法进行改进,提出一种两步测试方法,实现了在多径信道下的水声通信信号的开集识别。仿真实验表明:在归一化系数为0.5,信噪比等于10 dB条件下的归一化开集识别准确率达到90%以上,实测数据同样验证了本文方法的有效性。 展开更多
关键词 水声通信 调制方式识别 开集识别 两步测试流程
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Aspen Open Solver接口技术研究
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作者 陈智强 陈曦 +1 位作者 邵之江 张正江 《化工自动化及仪表》 CAS 2007年第4期34-38,共5页
以Aspen Open Solver接口集中的非线性代数方程组(NLA)部分作为研究对象,在对接口集进行系统地分析之后,利用AspenTech提供的接口代码将分别基于梯度和非基于梯度的四种求解算法嵌入生成solver组件,并实现用Aspen Plus调用该solver组件... 以Aspen Open Solver接口集中的非线性代数方程组(NLA)部分作为研究对象,在对接口集进行系统地分析之后,利用AspenTech提供的接口代码将分别基于梯度和非基于梯度的四种求解算法嵌入生成solver组件,并实现用Aspen Plus调用该solver组件观察各种算法嵌入的结果。 展开更多
关键词 ASPEN open Solver接口集 EO求解器 ASPEN PLUS 算法
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OpenFlow交换机协议一致性测试集模型研究
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作者 曾帅 殷志坚 《电信网技术》 2016年第5期67-69,共3页
针对当前的Open Flow交换机协议测试技术的研究现状,介绍了两个Open Flow交换机协议一致性测试的测试集模型。
关键词 open Flow交换机 一致性测试 测试集
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面向SAR解译的OpenSAR数据开放共享平台 被引量:3
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作者 项鹏 郭炜炜 +1 位作者 张增辉 郁文贤 《信息技术》 2016年第9期1-4,9,共5页
大量带有真值标注的数据集是SAR图像解译研究的重要基础和支撑。在推动SAR图像解译研究发展面临的诸多困难之中,缺少一个开放共享的数据集用于解译算法的研究和公平测试比较,是其中一个非常重要的因素。文中主要介绍构建的国内第一个面... 大量带有真值标注的数据集是SAR图像解译研究的重要基础和支撑。在推动SAR图像解译研究发展面临的诸多困难之中,缺少一个开放共享的数据集用于解译算法的研究和公平测试比较,是其中一个非常重要的因素。文中主要介绍构建的国内第一个面向SAR图像解译的数据开放共享在线平台:OpenSAR。详细介绍了OpenSAR平台的设计思想、功能组成、关键技术和已有数据集。通过该平台的构建,对于SAR解译研究能够取得良好的促进作用。 展开更多
关键词 SAR 开放共享 数据集 解译
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Solving open vehicle problem with time window by hybrid column generation algorithm 被引量:1
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作者 YU Naikang QIAN Bin +2 位作者 HU Rong CHEN Yuwang WANG Ling 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第4期997-1009,共13页
This paper addresses the open vehicle routing problem with time window(OVRPTW), where each vehicle does not need to return to the depot after completing the delivery task.The optimization objective is to minimize the ... This paper addresses the open vehicle routing problem with time window(OVRPTW), where each vehicle does not need to return to the depot after completing the delivery task.The optimization objective is to minimize the total distance. This problem exists widely in real-life logistics distribution process.We propose a hybrid column generation algorithm(HCGA) for the OVRPTW, embedding both exact algorithm and metaheuristic. In HCGA, a label setting algorithm and an intelligent algorithm are designed to select columns from small and large subproblems, respectively. Moreover, a branch strategy is devised to generate the final feasible solution for the OVRPTW. The computational results show that the proposed algorithm has faster speed and can obtain the approximate optimal solution of the problem with 100 customers in a reasonable time. 展开更多
关键词 open vehicle routing problem with time window(OVRPTW) hybrid column generation algorithm(HCGA) mixed integer programming label setting algorithm
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函数空间C_k(X)上的T-Tightness和Set-Tightness
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作者 杨春梅 李祖泉 《杭州师范大学学报(自然科学版)》 CAS 2011年第2期124-126,132,共4页
讨论了函数空间Ck(X)在赋予紧开拓扑下的T-tightness和set-tightness性质,利用开k覆盖获得了Ck(X)是T-tightness空间和set-tightness空间的两个对偶定理,将点态收敛拓扑函数空间Cp(X)的相关结论推广到紧开拓扑函数空间Ck(X)上.
关键词 函数空间 紧开拓扑 T—tightness set—tightness k覆盖
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