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71.
针对现阶段各规划边界交叉、空间重叠的问题,本文从提高空间价值、减少空间破碎度和协调各类空间的角度出发,在梳理现有空间优化模型及智能算法的基础上,改进多目标规划模型并适应性改造遗传算法,以此二者构建市级国土空间优化模型。以烟台市为例,设置3种情景为决策者提供方案集进行3类规划主导下的2020年国土空间优化研究,结果显示:①优化后烟台市农业、城镇和生态空间价值分别增加了23.24%、29.27%、6.30%;②不同情景下空间分布合理且较为集中,生态保护情景有利于国土空间集合连片,经济发展情景更适合于多空间协调发展。研究表明:该模型能有效地解决国土空间内容重叠问题,明显提高了国土空间价值,同时优化模型适应性强,为“多规合一”背景下市级国土空间优化提供技术支撑。 相似文献
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Forrest J. Bowlick Daniel W. Goldberg Sarah Witham Bednarz 《The Professional geographer》2017,69(1):138-150
Geographic information systems (GIS) are fundamental information technologies. The capabilities and applications of GIS continue to rapidly expand, requiring practitioners to have new skills and competencies, especially in computer science. There is little research, however, about how best to prepare the next generation of GIScientists with adequate computer science skills. This article explores how U.S. geography departments are introducing and developing computer science and programming skills in their geography and GIS degree programs. We review the degree requirements in fifty-five geography departments and discover that forty-four of them offer some kind of GIS programming course. Of the 210 separate degree options identified, however, only 22 require one of these courses for a degree. There is little consistency or emphasis on computer science and programming skills in geography or GIS degrees, despite the immense importance of these components in geography and GIS careers. We propose future research along distinct investigative tracks to build a research-based understanding of the educational interactions among GIS, computer science, programming, and geography. 相似文献
74.
利用大系统和模糊数学规划理论与方法,分析和探讨了水电站水库群模糊优化调度问题,建立了水电站水库群模糊优化调度模型,提出一种目标协调-模糊规划(IB-FP)法.理论分析和实例计算表明,所建立的模糊优化调度模型和提出的IB-FP法是可行和有效的. 相似文献
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76.
Simon Corne Tavi Murray Stan Openshaw Linda See Ian Turton 《Journal of Geographical Systems》1999,1(1):37-60
Measurements of water pressure beneath Trapridge Glacier, Yukon Territory, Canada show that the basal water system is highly
heterogeneous. Three types of behaviour were recorded: pressure records which are strongly correlated, records which are strongly
anticorrelated, and records which alternate between strong correlation and strong anticorrelation. We take the pressure in
bore-holes that are connected to the evacuation route for basal water as the forcing, and the other pressures as the response
to this forcing. Previous work (Murray and Clarke 1995) has shown that these relationships can be modelled using low-order
nonlinear differential equations optimized by inversion. However, despite optimizing the model parameters we cannot be sure that the final model forms are themselves optimal. Computational intelligence techniques provide alternative methods for fitting models and are robust
to missing or noisy data, applicable to non-smooth models, and attempt to derive optimal model forms as well as optimal model
parameters. Four computational intelligence techniques have been used and the results compared with the more conventional
mathematical model. These methods were genetic programming, artificial neural networks, fuzzy logic and self-organizing maps.
We compare each technique and offer an evaluation of their suitability for modelling the pressure data. The evaluation criteria
are threefold: (1) goodness of fit and an ability to predict subsequent data under different surface weather conditions; (2)
interpretability, and the extent and significance of any new insights offered into the physics of the glacier; (3) computation
time. The results suggest that the suitability of the computational intelligence techniques to model these data increases
with the complexity of the system to be modelled. 相似文献
77.
目前,大地电磁测深的资料处理与正、反演软件都是FORTRAN语言编写的,由于FORTRAN语言本身的局限性,使得这个软件存在很多的缺陷,但是因为用FORTRAN语言编写的算法已经比较成熟,将它全部用其他语言移植也比较费时费力,为了避免资料的浪费,提高大地电磁测深的资料处理与交互式系统的开发效率,并且更加完善其功能,在开发大地电磁测深二维交互式正反演系统时,对大地电磁测深中的计算部分仍用现有的FORTRAN程序,对有关的界面与图形诉开发部分用VC++语言来编写,以增强和体现其交互式的功能。 相似文献
78.
79.
W. Schaap 《Geotechnical and Geological Engineering》1984,2(1):51-61
Summary Recent mining literature on cutoff grade theory has come to reflect some viewpoints and analyses expressed earlier in the economic literature. Agreement is best when the cutoff grade policy is established by analysis in stages, starting from the limits of the deposit, and using the maximum net present value objective. In the derivation of the optimal cutoff grade policy a dynamic programming approach is then applied to solve the overall problem as a series of linked, nonlinear, stage optimization problems. A wholly satisfactory use of a dynamic programming methodology requires that two conditions be satisfied: the separability and optimality conditions. The former is, strictly, violated by a heap-leaching or dump-leaching process, the latter by possible forms of resource rent taxation. This paper considers the problem of including such a leaching process in a cutoff grade policy analysis along aforementioned lines. It concludes that a workable method of doing so may be found which, in particular, may be quite satisfactory in arid climates where, in addition, some practical leaching experience already exists. 相似文献
80.