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1.
讨论利用蚁群算法解决云计算资源的调度问题。蚁群算法利用正反馈机制加快了收敛速度,但同时具有易早熟,易陷入局部最优解等不足。针对此问题,提出用遗传算法优化蚁群优化算法,同时引入最大最小蚁群系统改进基本蚁群算法,从而形成新的遗传蚁群算法。实验结果表明,新算法应用于云计算资源调度中,能有效地缩短调度所用的平均时间,提高调度效率。  相似文献   

2.
基于改进蚁群算法的无人机低空公共航路构建方法   总被引:4,自引:0,他引:4  
日益增加的无人机数量和飞手自由规划航线给航空安全带来极大隐患。构建一个安全、高效的航空飞行环境,可以为无人机活动设立隔离空域,并在隔离空域内规划无人机低空公共航路,以提高低空空域利用率,为无人机交通管理提供决策依据。本研究充分考虑无人机近地表飞行及其即时通讯等特点,以天津市为例,基于地理信息技术构建以多源地理空间数据为基础的无人机低空飞行环境,包括低空蜂窝网络环境、大气环境和政策空域环境等,并改进传统蚁群算法以搜索无人机最优路径,得到该区无人机低空公共航路网。研究结果表明,改进的蚁群算法大大提高了路径搜索效率,满足无人机航路规划的高时效性、动态更新等要求;并且天津市航路长度符合市场上现有的无人机最远航程要求,基本满足现有的无人机运输要求。本研究描述的无人机低空公共航路研究的核心算法和关键技术,可以为无人机管控系统提供核心技术支撑。  相似文献   

3.
土地利用优化配置是促进土地可持续发展的重要举措,然而现有研究缺乏有效求解土地利用优化配置模型的新型混合式智能优化算法。本文结合蚁群算法和混沌模型,形成混沌蚁群优化(Chaos Ant Colony Optimization,CACO)算法,并以广州市增城区为研究区,对土地利用现状进行优化配置;然后在数量结构、目标函数值、空间布局等方面将优化结果与土地现状及标准蚁群算法优化结果进行对比分析。结果表明:① CACO算法能在满足多种约束条件下,有效解决多目标土地利用优化配置问题;② 与标准蚁群算法相比,CACO算法能增加土地利用的经济效益7.18亿元、生态效益0.33亿元、社会效益1.13%,同时降低地类转换成本1.15%;③ CACO算法能使土地利用现状空间分布多样性和均匀性的下降控制在1.30%以内,同时缩减地块数量8.86%,并使平均斑块大小增加9.77%,从而提升土地集约利用水平,更合理地配置各现状地类的空间分布,为研究区土地利用的科学规划与决策提供支持。  相似文献   

4.
栅格数据模型是地理信息科学领域的主要数据模型,成本距离分析是其重要的应用方向之一。但当栅格数据量较大时,传统的Dijkstra求解效率较低,因此本文提出了一种用改进蚁群算法来求解栅格成本距离的方法。首先,构建了适合人工智能算法的栅格数据模型及编码方法;然后,在此基础上初始化蚁群,采用状态概率选择机制计算相邻栅格单元之间距离成本,以及距离成本路径方向选择,同时利用改进的信息素更新机制加强蚁群之间信息交流,加快算法收敛速度;最后,引入了遗传算法的选择、交叉和变异等算子优化生产的成本距离的解,增加解的全局性。本文以北极地区的海冰密集度栅格数据为基础,求解北极地区适合航行路线的成本距离。实验表明,结合了蚁群算法和遗传算法优势的改进蚁群算法,能够快速有效地求解出基于栅格数据的成本距离。  相似文献   

5.
针对单一指派约束和容量约束的设施选址问题(Single Source Capacitated Facility Location Problem, SSCFLP),建立了一种基于改进蚁群算法与GIS的配送中心选址方法。构建了以总成本费用最小为目标的配送中心选址模型;提出了适合求解SSCFLP问题的改进双层蚁群算法,将求解过程划分为彼此关联的设施选择层和需求指派层2层蚁群,采用改进的全局信息素更新策略加强双层蚁群交流,并对迭代最优解的指派关系进行局部优化;将方法应用于汽车配送中心的选址,利用GIS工具构建选址空间。实验结果表明,该选址方法能找到质量较好的选址及指派结果,对于求解同类问题具有较强的借鉴意义。  相似文献   

6.
针对多面函数拟合法的中心节点难以选取的问题,提出将蚁群算法引入多面函数并结合稳健估计构建高精度拟合模型的方法。利用蚁群算法在复杂地形中快速寻找特征点,与少量非特征点共同作为中心节点参与模型构建,将稳健估计加入多面函数,运用选权迭代法剔除粗差对拟合模型的影响。GPS高程拟合数据处理实例表明,基于蚁群算法的多面函数结合稳健估计的拟合方法可有效剔除粗差的影响,且拟合精度比只用均匀格网法提高26%。  相似文献   

7.
8.
近年来,中国城市暴雨内涝频繁发生,已经发展成为一类严重的“城市病”。城市不透水面密度及其空间格局是形成暴雨内涝的一个重要影响因素。本文提出一种耦合蚁群算法和SCS-CN水文模型优化不透水面空间格局的方法,从而实现通过增加地面雨水渗透量达到减缓城市内涝发生的目的。首先应用Williams公式计算基于坡度修正的CN值,在此基础上计算地表径流量;然后设定径流系数最小化目标,耦合水文模型和蚁群算法对径流小区尺度的不透水面空间格局进行优化配置;最后应用景观格局指数对不透水面空间格局进行分析。研究结果表明:面对1年、5年、10年、20年、50年以及100年一遇重现期的1 h持续降雨事件,研究区优化后的不透水面空间格局可以分别减少径流系数21.19%、19.58%、19.38%、18.93%、18.41%和17.25%,在一定程度上缓解城市暴雨内涝的发生。在此基础上,提出面向暴雨内涝防治的城市更新优化措施建议:① 通过增加草地、花园、树木等植被绿化减少高不透水面类型的面积,并划分成更多中高不透水面类型的斑块;② 集聚低、中低等不透水面类型,从而加大连通性,形成更多的中高不透水面类型;③ 增加每个径流小区内斑块数量,增大斑块密度,减少其蔓延度和聚集度。  相似文献   

9.
大规模点要素注记自动配置问题是地图注记的难点之一,主要受限于时间效率和注记配置质量。针对该问题,本文首先提出一种椭圆形多方位多级注记待选方位配置方案,使其参数化、多元化。其次,结合点要素空间分布特征,提出一种以聚类分组的蚁群算法,并讨论和优化核心参数,实现大规模点要素的注记快速配置。实验表明,该算法计算效率明显提升,算法性能稳定。针对注记密度在5%~30%随机分布点要素的地图,其相比传统蚁群算法算法效率提高73.2%;同时,该算法的注记结果质量比传统蚁群算法注记结果质量好,注记适应度提升8.0%。实验采用抚顺县集体土地所有权界址点数据进行验证,结果表明效率提升86.7%,且注记适应度提升14.6%。本算法适用于点要素规模大、点簇疏密变化差异大的点要素注记自动配置问题的快速求解。  相似文献   

10.
蚁群算法是近年来出现的一种新的仿生优化算法.针对基本蚁群算法在求解过程中容易出现收敛时间过长以及易陷入局部最优解的不足,对算法中的状态转移、搜索方式以及信息素更新进行改进,提出了一种新的改进蚁群算法.一类典型旅行商问题的仿真实验表明改进的蚁群算法具有收敛速度快、全局搜索能力强和计算时间短的特点,证明了方法的可行性和有效性.  相似文献   

11.
It is an effective way in realizing urban coordinated and sustainable development to establish a series of indicators and to evaluate urban environmental and socioeconomic development. According to the characteristics of Harbin City in Northeast China, an indicator system including five subsystems and 37 indicators was established for comprehensive evaluation on urban sustainable development. The development indexes of all urban subsystems and complex system were calculated quantitatively using the comprehensively integrated methods composed of Principle Component Analysis, Analytic Hierarchy Process and weighed index method, and then the comprehensive level of urban sustainable development and the degree of urban interior coordination were analyzed. The results indicated that 1) the overall urban development presented an uptrend, however, the interior development was not well balanced from 1996 to 2006; 2) the development in each subsystem presented a strong fluctuation; and 3) the development in resources subsystem showed a downtrend. Based on those results, the suggestions of urban sustainable development were put forward at the end.  相似文献   

12.
13.
在分析可持续发展指标特征基础上,提出按持续、协调、结构和集聚四类建立可持续发展分类单项指标指数公式和综合指数公式,并用遗传算法对公式中参数进行优化,建立了可持续发展的综合指数评价模型。该模型应用于乌鲁木齐市的可持续发展评价结果与实况分析结果基本一致,该模型有简单、实用的特点。  相似文献   

14.
There exists synchronous growth in resources consumption and environment pollution in Kunming urbanization in recent years, which has led to the increasing pressure of urban sustainable development. Considering the environmental and social benefits in Kunming’s water resources sustainable development, the authors provided a research finding the optimal urban population scale in different stages for urban water supply based on the sustainable development groundwater evaluating theoretical model. Through the research on the availability of construction site as well as the risk in underground space exploitation with the extenics theory method, we get a suitable partition map of land for urban construction and a risky partition map of underground space development. The results show that the appropriate population scale of Kunming will be less than 2.96×106 by 2020, and will reach (4.34--2.96)×106 optimized population scale after 2020 under the condition of economic-socially and environmentally sustainable development. It is significant to optimize urban construction land and use underground space under the condition of land resources sustainability in Kunming.  相似文献   

15.
Kunming Basin locates middle of Yunnan altiplano and has a particularity in geography,topographic and geological environment.With the urban dilation quickly,add the reason of the unreasonable city layout,conflicts between environment and urban resources consumption become shrill increasingly.It is human being activities that lead to vulnerability and depravation of geological environment in local.Take a few examples on geological environment to expatiate relationship between urban construction and geological environment carrying capacity,and find a way how to make a better plan for urban sustainable development to achieve new balance between man and nature in local.  相似文献   

16.
Kunming Basin locates middle of Yunnan altiplano and has a particularity in geography, topographic and geological environment. With the urban dilation quickly, add the reason of the unreasonable city layout, conflicts between environment and urban resources consumption become shrill increasingly. It is human being activities that lead to vulnerability and depravation of geological environment in local. Take a few examples on geological environment to expatiate relationship between urban construction and geological environment carrying capacity, and find a way how to make a better plan for urban sustainable development to achieve new balance between man and nature in local.  相似文献   

17.
城市化进程与城市可持续发展   总被引:2,自引:0,他引:2  
全球城市化在带动经济发展的同时也带来了一系列的问题,即所谓的“城市病”,实现城市可持续发展是解决这些问题的必由之路,在分析城市化现象带来的问题之后,讨论了实施城市可持续发展的可行性和必要性,并就如何实施我国城市可持续发展提出了一些建议。  相似文献   

18.
In order to solve the problems of multi-parameter, multi-extreme and multi-solution in the nonlinear iterative optimization process of Rayleigh wave inversion, the artificial bee colony(ABC)algorithm is selected for global nonlinear inversion. The global nonlinear inversion method does not rely on a strict initial model and does not need to calculate the derivative of the objective function. The ABC algorithm uses the local optimization behavior of each individual artificial bee to finally highl...  相似文献   

19.
财务指标是企业盈利能力的反映。根据近几年的相关数据,通过对财务指标综合分析,探讨四川省上市公司的可持续发展状况。  相似文献   

20.
Sustainable development is a complex and systemic issue. It is essential to study it by the component analysis method from the view of system science. The urban developmental sustainability is one of focuses that people has paid more attention to, however, little common understanding how to measure and evaluate the sustainability has been gotten. In this paper, a framework is designed to evaluate the developmental sustainability of Suihua City, Heilongjiang Province in China from the aspects of economy, society, population, resources and environment. We adopt the Principal Components Analysis (PCA) to decrease dimensions and simplify the original indexes into 12 indexes. Also, the hierarchy and comprehensive multiple-criterion evaluative methods are employed to assess the sustainable development system in Suihua City. Then, the weights of indexes are attained by Analytic Hierarchy Process (AHP) method. Furthermore, urban comprehensive development level, developmental sustainability, coordinate degree are calculated and analyzed. By analyzing, we know the fluctuation of development level of subsystem, especially resources and environment subsystem, is acute. The comprehensive development level of sustainable development system in Suihua has been on the rise since 1999. That results from the effect of traditional economic development mode with high energy-consumed being decreased in the city after 1999. At the same time, it is obvious that there was an instability of development level in Suihua City during 1990-2002, with a turn in 1998, and the development could be sustainable, the status trend was more harmonious in 1999-2002.  相似文献   

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