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1.
刘殿锋  刘耀林  赵翔 《测绘学报》2013,42(5):722-728
提出一种基于多目标微观邻域粒子群的土壤空间优化抽样方法。方法面向土壤空间调查的多目标特征,构建了基于最小克里金方差(MKV)和极大熵准则(ME)的粒子群多目标适应度函数,设计了最小样本量限制、样点可达性、采样成本限制和最小空间关联性四类粒子微观邻域操作策略,能高效协调土壤空间抽样精度、代表性、成本、样本量与样点布局等多目标冲突。实验结果表明,相比单目标粒子群算法和模拟退火算法,该方法的目标冲突协同能力强、收敛效率高,所设计抽样方案最优,为土壤质量精确调查与高效监测提供了技术支持。  相似文献   

2.
龚健雅  钟燕飞 《遥感学报》2016,20(5):733-747
随着对地观测技术的发展,海量遥感影像不断传输到地面。传统的遥感信息处理方法在处理效率、精度上的不足,限制了遥感信息的挖掘及利用,亟需发展智能化方法满足遥感影像处理的需求。受自然界中生物进化机制的启发,基于进化计算的遥感影像智能化处理方法具有以下特点:(1)拥有全局优化能力,对目标函数的优化能力更强;(2)具有自组织、自学习的特点,能够从遥感数据本身学习,不依赖数据分布等先验信息;(3)拥有处理多目标问题的能力,同时考虑多个目标函数而不需要人工确定它们之间的权重。因此,智能化遥感信息处理方法能够在海量遥感影像中有效地提取适用于不同应用目的的信息。本文主要介绍智能化遥感信息处理方法的典型应用包括遥感影像智能化分类(监督分类、聚类)、遥感影像亚像素信息提取(高光谱影像混合像元分解、亚像元制图),并讨论了遥感信息智能化处理方法的发展方向。  相似文献   

3.
本文探讨适合于工程控制网的二类优化设计方法。文章通过对准则矩阵合理设计的讨论,构造了适合于工程控制网的二类优化设计的模型,并讨论了相应数值解算方法。  相似文献   

4.
A genetic algorithm based approach is used in this paper for the selection of a subset from the combination of Wavelet Packet Statistical and Wavelet Packet Co-occurrence textural feature sets to classify the LISS IV satellite images using neural networks. Generally, adding a new feature increases the complexity of training and classification. Hence there is a need to differentiate between those features that contribute ample information and others. Many current feature reduction techniques such as Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) involve linear transformations of the original pattern vectors to new vectors of lower dimensions. Hence a multi-objective Genetic Algorithm has been employed to reduce the complexity and increase the accuracy of classification. Four indices - user’s accuracy, producer’s accuracy, overall accuracy and kappa co-efficient are used to assess the accuracy of the classified data. Experimental results show that the proposed Genetic Algorithm approach with lesser number of optimal features produces comparable results with that of our earlier approach using more features.  相似文献   

5.
In this paper, we propose a method of cost distribution analysis of new consumer connections to a city power grid by accounting for spatial restrictions and characteristics of existing networks. In practice, the calculation of connection costs for each new consumer includes the network design and financial expenditure. We suggest that connection costs should be calculated for the whole city based on the normative parameters at the stage when the object location is selected by investors and when power grid development is planned by power companies. The proposed method enables the modeling of new power line connection routes from every parcel of city land to possible points of connection to the operating networks based on the raster design of the area. The optimal path is chosen by one criterion consisting of two components: the costs of both laying new power lines and providing sufficient power reserve in the chosen network connection point. Realized as a computer program, the method has been used to calculate the costs of connections to low-voltage power lines.  相似文献   

6.
采用生态足迹法对云南孟连县2005—2011年生态足迹进行计算,根据2005—2011年数据运用GM(1,1)灰色预测模型对2020年生态足迹进行预测,得到2020年人均生态赤字将达到2.762 hm2/人,土地利用结构急需调整优化。在此背景下建立以生态赤字最小化和经济效益、社会效益最大化为目标函数的多目标线性规划模型,设置了8个变量和13个约束条件。根据模型求解优化方案,对孟连县2020年土地利用结构进行优化调整,结果表明:相比于优化前,人均生态赤字减少10.87%,经济效益增加0.52亿元,社会效益增加0.001 hm2。优化后的土地利用结构基本上实现了经济、社会、生态效益的统一。  相似文献   

7.
The general problem of the optimal design for a geodetic network subject to any extrinsic factors, namely the first-order design problem, can be dealt with as a numeric optimization problem. The classic theory of this problem and the optimization methods are revised. Then the innovative use of the simulated annealing method, which has been successfully applied in other fields, is presented for this classical geodetic problem. This method, belonging to iterative heuristic techniques in operational research, uses a thermodynamical analogy to crystalline networks to offer a solution that converges probabilistically to the global optimum. Basic formulation and some examples are studied.  相似文献   

8.
基于数字地图的多属性最优路径问题的算法研究   总被引:3,自引:0,他引:3  
以某地理信息系统的数字地图为背景,通过综合数字地图交通道路层的几个属性来设置权值,并改善矩形框搜索区域算法,使之适用于地理信息系统下交通道路网的最优路径计算,提高了Dijkstra算法的效率。  相似文献   

9.
姚勤 《测绘学报》1992,21(1):25-33
本文根据模拟法控制网优化设计的特点,对由观测值权的改变而产生的精度目标函数。增益进行了理论分析。提出优化设计的精度价格比概念,从而导出受约于一定经济及可靠性的优化设计准则;针对观测值权的优化设计,又导出权分配的最佳调整准则;最后提出了目标函数增益值的直接迭代算法。实践证明,利用此方法进行优化设计,在不需设计者的经验干预下,能快速得到既满足精度要求而又经济合理的控制网布设方案 。  相似文献   

10.
测量极值问题的经验解式--兼论绝对和极小问题   总被引:4,自引:0,他引:4  
周江文 《测绘学报》1999,28(1):11-14
测量上有许多极值问题,如各种准则下的平差,权的最优分配,网的优化方案等,多可归于线性极值问题,且多不适用寻常数学解法。但同型问题往往已经作过多次解算。因此本文以单纯形法为主,强调利用已有经验,直接逼近优解,或经少数次迭进达到优解,然后极值条件加以验证。为此文中着重提出通用解式及优解条件,期能得出优解公式,有相当的适用范围。  相似文献   

11.
In the design of a global navigation satellite system receiver, the tracking performance depends on the code tracking loop and the associated discriminator. An adaptive code discriminator under a multi-correlator architecture has been designed based on a multi-objective principle to achieve a balance among various, sometimes conflicting, design objectives. With the proposed optimization approach and adaptive logic, concerns of large pull-in region and small steady-state error can be addressed. The proposed scheme is implemented in a digital signal processor/field programmable gate array board and an experiment is conducted to process GIOVE-A signals. The test results reveal the advantages of the proposed code tracking architecture and discriminator design.  相似文献   

12.
胡国荣 《测绘工程》1996,5(1):26-31
在监测网设计阶段,不仅要考虑不同变形模型之间的可区分度,而且要研究变形与粗差的可区分度,即双可区分度,以利以后进行变形分析。文中导出了变形与粗差的可区分度,并以双可区分度为准则进行监测网非线性动态优化设计。同时给出了一个非线性直接优化算法,该算法避开了常规的台劳级数线性展开的方法,易于在计算机上实现。  相似文献   

13.
本文结合优化设计中解析法和机助法两者的特点,利用各类典型图形进行优化设计和模拟计算,从而归纳出一些规律性的结论,以指导网的布设。  相似文献   

14.
换乘信息特别是基于地理信息系统技术的图文换乘信息服务,已经成为城市公共交通信息服务、线网规划和线路优化调整的重要指标与内容。但是公共交通线网具有特殊的网络特征和拓扑关系,它不同于城市道路网络,因此公共交通换乘不能简单应用于目前的最优路径算法,例如Dijkstra算法。本文将通过对公共交通线网的空间特征和语义(交通)规则分析,建立城市交通网络的几何和语义连通性的集成关系。几何连通性是语义连通性的基础和先决条件,而语义连通性是公共交通网络拓扑的核心。基于语义连通性的公共交通线网拓扑关系提升公共交通换乘算法的效率和信息准确度,任何两个站点之间的最优路径可以被迅速获取而不需要检索整个网络的几何拓扑信息。并且该最优换乘路径考虑到最少换乘次数、出行距离最短、费用最少、途经站点最少和换乘中最短步行距离等多目标换乘。  相似文献   

15.
GPS vector configuration design for monitoring deformation networks   总被引:1,自引:0,他引:1  
 The performance of geodetic monitoring networks is heavily influenced by the configuration of the measured GPS vectors. As an effective design of the GPS measurements will decrease GPS campaign costs and increase the accuracy and reliability of the entire network, the identification of the preferred GPS vectors for measurement has been highlighted as a core problem in the process of deformation monitoring. An algorithm based on a sensitivity analysis of the network, as dependent upon a postulated velocity field, is suggested for the selection of the optimal GPS vectors. Relevant mathematical and statistical concepts are presented as the basis for an improved method of vector configuration design. A sensitivity analysis of the geodetic geodynamic network in the north of Israel is presented, where the method is examined against two deformation models, the Simple Transform Fault and the Locked Fault. The proposed method is suggested as a means for the improvement of the design of monitoring networks, a common practice worldwide. Received: 30 July 2001 / Accepted: 3 June 2002 Acknowledgments. It is my pleasant duty to thank the Survey of Israel and Dr. E. Ostrovsky for providing the variance–covariance matrix of the G1 network in northern Israel. I would like to thank the reviewers of this paper for their constructive and helpful remarks.  相似文献   

16.
整数规划在施工控制网观测精度优化设计中的应用   总被引:2,自引:1,他引:2  
岑敏仪 《测绘学报》1992,21(1):34-41
使用数学解法来获得最优的控制网观测量的权,必须转换成观测方案后才能实现。怎样才能使转换后的观测方案既避免主观因素的影响,又具有最优的设计功能,是本文所力图解决的问题。文章顾及施工控制网原始数据误差的影响,提出利用整数规划进行观测精度优化设计的数学模型和计算方法,使优化设计理论更趋完美。文章最后通过算例说明该法在控制网观测精度优化设计中的作用。  相似文献   

17.
讨论了工程控制网观测纲要的最优化设计,同时,还把网的可靠性作为一个重要的设计指标,用以限制观测粗差对控制网的影响。  相似文献   

18.
19.
 The proper and optimal design and subsequent assessment of geodetic networks is an integral part of most surveying engineering projects. Optimization and design are carried out before the measurements are actually made. A geodetic network is designed and optimized in terms of high reliability and the results are compared with those obtained by the robustness analysis technique. The purpose of an optimal design is to solve for both the network configuration (first-order design) and observations accuracy (second-order design) in order to meet the desired criteria. For this purpose, an analytical method is presented for performing the first-order design, second-order design, and/or the combined design. In order to evaluate the geometrical strength of a geodetic network, the results of robustness analysis are displayed in terms of robustness in rotation, robustness in shear, and robustness in scale. Results showed that the robustness parameters were affected by redundancy numbers. The largest robustness parameters were due to the observations with minimum redundancy numbers. Received: 14 August 2000 / Accepted: 2 January 2001  相似文献   

20.
本文从两个准则矩阵——精度准则矩阵与可靠性准则矩阵出发,导出了一种新的测量控制网优化设计方法。利用它不仅能实现同时顾及精度与可靠性的二类优化设计,还可进行以准则矩阵为基础的一类优化设计。另外,这种方法可将一类、二类设计问题同时解决,从而为测量控制网的混合设计开辟了新路。  相似文献   

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