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1.
The Harmony Search (HS) is a metaheuristic algorithm, which is inspired from the composition of music harmonies. The functionality and flexibility of HS contribute to the development of successful methodologies for different kind of scientific problems. The aim of this paper is to propose a variant of the classic HS algorithm in order to provide competitive solutions for the Team Orienteering Problem (TOP). We introduce the Similarity Hybrid Harmony Search (SHHS) algorithm as an alternative and innovative optimization method. The SHHS follows the standard procedure of HS with some modifications and includes a new strategy called “similarity process”. Two versions of the proposed method have been developed, the static version with predefined values for the parameters of the method and the dynamic one with dynamic adjustment of the parameters. The SHHS algorithm is applied to the known benchmark instances of TOP. The dynamic of the algorithm is tested through a complete solution analysis which gives the superiority of the dynamic version compared to the static one. The results of both versions of the proposed algorithm indicate the positive performance against other effective and robust optimization algorithms from the literature. 相似文献
2.
Daodi Flood Land, located in Mentougou District of Beijing, is a relatively separate flood land in the lower reaches and on the east of Yonding River. This largest landscape character area in the west of Beijing along the river illustrates the history of human–water interaction and discloses the trends and problems of rural urbanization. Focusing on Daodi Flood Land, this paper expands the research on adaptation by introducing basic concepts and research framework, and reviews the research trends from spatial, temporal, and participant aspects. Considering the typical characters of the study area, this research employed participatory approaches, such as mapping and problem and solution trees, due to the lack of continuous and accurate data. Basing on literature review and field investigation on issues of floods, agricultural irrigation, and water resource utilization, water adaptive development visions for the study area were proposed from perspectives of landscape and culture. Finally, the paper further analyzes the structural relations between adaptation problems, natural and social systems, passive and active adaptations, and planned and unplanned adaptations, with the aim to provide reference for relevant studies and applications of adaptation approaches in other cases. 相似文献
3.
当前,社会发展进入十三五新时代,以人为本充分体现了对社会生产中劳动力的强烈关注,因此安全生产是企业得以发展的最基础保证。石油企业作为国民经济的支柱产业,但又是高危行业,安全形势十分严峻。因此安全管理成为石油企业急需深入探究的问题。文章分析了石油企业目前在安全管理方面存在的问题,提出了在安全管理上采取的一些方法和措施。 相似文献
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Multi Compartment Vehicle Routing Problem is an extension of the classical Capacitated Vehicle Routing Problem where different products are transported together in one vehicle with multiple compartments. Products are stored in different compartments because they cannot be mixed together due to differences in their individual characteristics. The problem is encountered in many industries such as delivery of food and grocery, garbage collection, marine vessels, etc. We propose a hybridized algorithm which combines local search with an existent ant colony algorithm to solve the problem. Computational experiments are performed on new generated benchmark problem instances. An existing ant colony algorithm and the proposed hybridized ant colony algorithm are compared. It was found that the proposed ant colony algorithm gives better results as compared to the existing ant colony algorithm. 相似文献
6.
工程教育是我国高等教育的重要组成部分,工程教育认证已成为中国高校新的风向标,也成为高考生选择报考专业的一项重要指标。设计模式是计算机科学与技术专业的一门核心课程,包含了面向对象的精髓,是软件体系结构的基础,在工程教育认证所评估的课程设置中起着承上启下的关键作用。本文基于工程教育专业认证理念,以及山东农业大学申请认证所用的《计算机科学与技术专业培养方案》,从教学内容、教学方式、课程目标与毕业要求对应关系、解决复杂工程问题能力、教学进度安排等方面,对设计模式课程开展了教学研究,并将该教学方案应用于本科教学。 相似文献
7.
全同态加密体制能够在不解密的条件下对密文进行任意的函数运算,是解决云计算中数据隐私保护难题的关键技术。构造全同态加密方案的核心是有效控制密文同态运算中的噪声增长,稀疏子集和问题是实现该目标所需的基本困难性问题。针对基于该问题困难性的全同态加密方案,提出一种改进的反馈攻击方法,使攻击者可以对公钥中的部分数据进行特定计算,通过访问解密谕示得到完整的私钥。分析结果表明,该方法能够充分利用预计算提高攻击效率,对基于稀疏子集和问题的全同态加密方案具有良好的适用性。 相似文献
8.
The Order Batching Problem is an optimization problem belonging to the operational management aspect of a warehouse. It consists of grouping the orders received in a warehouse (each order is composed by a list of items to be collected) in a set of batches in such a way that the time needed to collect all the orders is minimized. Each batch has to be collected by a single picker without exceeding a capacity limit. In this paper we propose several strategies based on the Variable Neighborhood Search methodology to tackle the problem. Our approach outperforms, in terms of quality and computing time, previous attempts in the state of the art. These results are confirmed by non-parametric statistical tests. 相似文献
9.
随着信息时代的来临,在信息大爆炸以及经济全球化的背景下,电子商务作为经济时代的产物正在繁荣的发展着,它改变了我们传统概念中的商务模式,为企业的发展开启了一扇明亮而广阔的市场大门,也为各国的经济发展贡献出了一份不可小觑的力量。 相似文献
10.
伴随着我国现代化科技水平不断的提高与完善,电气工程自动化也越来越被人们所重视.但在取得了一定程度发展的同时,也存在着大量的问题隐患,因此要结合目前所存在着的问题采取适当的科学化方法策略来予以处理,以便能够实现对电气工程以及相关自动化技术的创新发展.本文将重点针对电气工程及其自动化的常见问题展开具体分析,并提出了一些针对性的应对方法. 相似文献