Book Review     

Neil Stuart 《International journal of geographical information science》2013,27(6):601-602

In this paper, we examine the applicability of spatial optimization as a generative modelling technique for sustainable land‐use allocation. Specifically, we test whether spatial optimization can be used to generate a number of compromise spatial alternatives that are both feasible and different from each other. We present a new spatial multiobjective optimization model, which encourages efficient utilization of urban space through infill development, compatibility of adjacent land uses, and defensible redevelopment. The model uses a density‐based design constraint developed by the authors. The constraint imposes a predefined level of consistent neighbourhood development to promote contiguity and compactness of urban areas. First, the model is tested on a hypothetical example. Further, we demonstrate a real‐world application of the model to land‐use planning in Chelan, a small environmental amenity town in the north‐central region of the State of Washington, USA. The results indicate that spatial optimization is a promising method for generating land‐use alternatives for further consideration in spatial decision‐making.  相似文献   

Introducing scale parameters for adjusting area objects in GIS based on least squares and variance component estimation     

Xiaohua Tong  Wenzhong Shi  Dajie Liu 《International journal of geographical information science》2013,27(11):1413-1432

In this paper, a least‐squares based cadastral parcel area adjustment in geographic information systems (GIS) is developed based on (1) both the areas and coordinates being treated as observations with errors; and (2) scale parameters being introduced to take the systematic effect into account in the process of cadastral map digitization. The area condition equation for cadastral parcel considerations of scale parameters and geometric constraints is first constructed. The effects of the scale error on area adjustment results are then derived, and statistical hypothesis testing is presented to determine the significance of the scale error. Afterwards, Helmert's variance component estimation based on least‐squares adjustment using the condition equation with additional parameters is proposed to determine the weight between the coordinate and area measurements of the parcel. Practical tests are conducted to illustrate the implementation of the proposed methods. Four schemes for solving the inconsistencies between the registered areas and the digitized areas of the parcels are studied. The analysis of the results demonstrates that in the case of significant systematic errors in cadastral map digitization, the accuracies of the adjusted coordinates and areas are improved by introducing scale parameters to reduce the systematic error influence in the parcel area adjustment. Meanwhile, Helmert's variance component estimation method determines more accurate weights of the digitized coordinates and parcel areas, and the least‐squares adjustment solves the inconsistencies between the registered areas and the digitized areas of the parcels.  相似文献   

A Voronoi neighborhood-based search heuristic for distance/capacity constrained very large vehicle routing problems     

Zhixiang Fang  Shih-Lung Shaw  Shunqing Chen  Bi Yu Chen 《International journal of geographical information science》2013,27(4):741-764

Local search heuristics for very large-scale vehicle routing problems (VRPs) have made remarkable advances in recent years. However, few local search heuristics have focused on the use of the spatial neighborhood in Voronoi diagrams to improve local searches. Based on the concept of a k-ring shaped Voronoi neighbor, we propose a Voronoi spatial neighborhood-based search heuristic and algorithm to solve very large-scale VRPs. In this algorithm, k-ring Voronoi neighbors of a customer are limited to building and updating local routings, and rearranging local routings with improper links. This algorithm was evaluated using four sets of benchmark tests for 200–8683 customers. Solutions were compared with specific examples in the literature, such as the one-depot VRP. This algorithm produced better solutions than some of the best-known benchmark VRP solutions and requires less computational time. The algorithm outperformed previous methods used to solve very large-scale, real-world distance constrained capacitated VRP.  相似文献   

A spatially explicit methodology for a priori estimation of field survey effort in environmental observation networks     

Carlos Guerra  Marc J. Metzger  João Honrado  Joaquim Alonso 《International journal of geographical information science》2013,27(10):2077-2098

When establishing environmental monitoring programmes, it crucial to make reliable cost estimates, especially where a field survey is involved. This paper presents a methodology for creating a spatial measure of a field survey effort (SE). A set of relevant variables affecting a SE (e.g. areas with rough terrain, or distant from the main road network) was classified using fuzzy sets and then combined to produce spatially explicit effort indicators, which were integrated to a single measure using an analytic hierarchy process (AHP). To evaluate this approach and identify the limits for its application, three spatially nested case studies were used to test the spatial expression of SE and the scalable capacity of the method itself. The presented methodology could cope with variations in the scale and data resolution, retrieving a coherent estimate of SE across the different case studies. The presented methodology is therefore useful for (i) testing the network designs for sampling bias related to SE, (ii) comparing alternative sampling designs, (iii) assessing the sampling costs and (iv) supporting the human and logistical resource management.  相似文献   

An improved ant colony optimization (I-ACO) method for the quasi travelling salesman problem (Quasi-TSP)     

Jianyi Yang  Ruifeng Ding  Yuan Zhang  Maoqin Cong  Fei Wang 《International journal of geographical information science》2013,27(9):1534-1551

Traveling salesman problem (TSP) and its quasi problem (Quasi-TSP) are typical problems in path optimization, and ant colony optimization (ACO) algorithm is considered as an effective way to solve TSP. However, when the problems come to high dimensions, the classic algorithm works with low efficiency and accuracy, and usually cannot obtain an ideal solution. To overcome the shortcoming of the classic algorithm, this paper proposes an improved ant colony optimization (I-ACO) algorithm which combines swarm intelligence with local search to improve the efficiency and accuracy of the algorithm. Experiments are carried out to verify the availability and analyze the performance of I-ACO algorithm, which cites a Quasi-TSP based on a practical problem in a tourist area. The results illustrate the higher accuracy and efficiency of the I-ACO algorithm to solve Quasi-TSP, comparing with greedy algorithm, simulated annealing, classic ant colony algorithm and particle swarm optimization algorithm, and prove that the I-ACO algorithm is a positive effective way to tackle Quasi-TSP.  相似文献   

A new composition-sensitive parameter for ultra-high energy cosmic rays     

G. Ros  A.D. SupanitskyG.A. Medina-Tanco  L. del PeralJ.C. D’Olivo  M.D. Rodríguez Frías 《Astroparticle Physics》2011,35(3):140-151

A new family of parameters intended for composition studies in cosmic ray surface array detectors is proposed. The application of this technique to different array layout designs has been analyzed. The parameters make exclusive use of surface data combining the information from the total signal at each triggered detector and the array geometry. They are sensitive to the combined effects of the different muon and electromagnetic components on the lateral distribution function of proton and iron initiated showers at any given primary energy. Analytical and numerical studies have been performed in order to assess the reliability, stability and optimization of these parameters. Experimental uncertainties, the underestimation of the muon component in the shower simulation codes, intrinsic fluctuations and reconstruction errors are considered and discussed in a quantitative way. The potential discrimination power of these parameters, under realistic experimental conditions, is compared on a simplified, albeit quantitative way, with that expected from other surface and fluorescence estimators.  相似文献   

基于IRCGA优化的GM(1,1)变形预测方法与应用研究     

喻巧  张献州  陈超  刘龙 《测绘与空间地理信息》2013,(12):42-45

阐述了引入时间距离权的传统GM(1,1)模型的建模过程以及灰色模型等级的判断方法,深入分析了白化背景参数λ取值对建模精度的影响;同时针对传统λ取值的缺陷,提出使用基于实数编码的改进遗传算法(IRCGA)对其进行优化处理,并用多个工程实例分析验证了优化后的GM(1,1)模型相对传统的灰色模型及其优化模型拟合效果更好,更加贴近真实数据序列。  相似文献   

南黄海浮游植物与水色透明度之间相关关系的研究   总被引：1，自引：0，他引：1  

李宝华  傅克忖 《海洋科学进展》1999,(3)

本文根据 １９９５ 年 ９ 月在南黄海获取的资料,分析和讨论了该水域浮游植物现存量（叶绿素 ａ （ Ｃ Ｈ ））、初级生产力（ Ｐ Ｐ） 和海水光学参数（透明度（ Ｓ Ｔ））、水色（ Ｗ Ｃ）） 之间的相关关系。分析结果表明,夏末秋初南黄海 Ｃ Ｈ 与 Ｐ Ｐ, Ｃ Ｈ 与 Ｗ Ｃ 和 Ｐ Ｐ 与 Ｗ Ｃ 以及悬浮物（ Ｓ Ｓ） 与 Ｗ Ｃ 之间均有良好的正相关关系。相关式分别为： Ｐ Ｐ ＝ ２２５１９ｌｎ（ Ｃ Ｈ ） ＋ ４８８９１ 或 Ｐ Ｐ ＝ ５ Ｅ－ ０５ Ｃ Ｈ １６４６４（ Ｒ２ ＝ ０７０３７）; Ｗ Ｃ ＝ ４０３ｌｎ（ Ｃ Ｈ ） ＋ ８９７６８ 或 Ｗ Ｃ ＝ ７１３０６ Ｃ Ｈ ０４７４７ （ Ｒ２ ＝０７９２１）; Ｃ Ｈ ＝ １５４３７ｌｎ（ Ｓ Ｓ） ＋ １３６４７ 或 Ｃ Ｈ ＝ ０７４９９ Ｓ Ｓ１２５２（ Ｒ２ ＝ ０７２２３）; Ｐ Ｐ ＝３３２８６ｌｎ Ｓ Ｓ＋ １５２２２ 或 Ｐ Ｐ ＝ ３３０２９ Ｓ Ｓ０５６９４ （ Ｒ２ ＝ ０５４７６）; Ｐ Ｐ ＝ ４２５８８ｌｎ（ Ｗ Ｃ） － ３７０７１或 Ｐ Ｐ ＝ ６６５１２ Ｗ Ｃ０８６６５（ Ｒ２ ＝ ０６７３１） 以 及 Ｓ Ｓ ＝ １４０１９ｌｎ（ Ｗ Ｃ） － １３３６３   相似文献   

非精确搜索一维全局最优化方法     

李博  曹圣山 《中国海洋大学学报(自然科学版)》1999,(3)

研究一维全局最优化问题的确定性求解方法。运用逐次建立目标函数的线性下界函数,将不含全局最优解的子区域删除,并基于非精确搜索结合下降算法而得出非精确搜索一维全局最优化方法,使计算量减少且使迭代收敛加快。迭代结束时该算法得到一维全局最优化问题的ε－全局最优解。该方法具有有限收敛性且不需精确的局部优化过程。文中的数值实例表明该算法的有效性。  相似文献   

Optimum Design of Structure Shape for Offshore Jacket Platforms   总被引：1，自引：1，他引：0  

FENG Sheng 《中国海洋工程》2000,14(4):435-445

With the introduction of the design variables of nodal coordinates,which reflect the em-bedded depth of the pile and the jacket bed height,a shape optimum design model for offshore jacket plat-forms is established.A sequential two-level optimum algorithm is developed based on the design variablegradation.On the basis of the finite element method,the sensitivity of the objective function and nodal dis-placement is analyzed.As an example,the BZ281 oil storage offshore platform,which lies in the Bohai oilfield,is designed with the shape optimum model.The results are compared with the cross-section optimumdesign.The tendency of design variables and its reasons in the two methods are analyzed.In the shapeoptimum design,the value of objective function is obviously smaller than that of the initial design and thecross-section optimum design.Therefore,the advantage of structure shape optimum design for jacket plat-forms is remarkable.  相似文献