首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
空间数据库建设的规则概念贯穿于整个工作对象、工作过程、工作结果。实践表明:对现有空间数据建设规则理解的正确与否在很大的程度上决定着空间数据库设计的成败,本文结合区域水文地质信息的特性,阐述了建库过程中为使区域水文地质信息达到多学科共享而设立的具体规则,为后期区域水工环空间数据库建设提供有效的参考途径,从而更好的为相关项目的顺利完成提供了技术支撑。  相似文献   

2.
土方计算精度与方格网边长之关系的研究   总被引:13,自引:0,他引:13  
通过对方格网法在大比例尺地形图上计算挖(填)土石言精度的讨论,澄清了方格网边长与土石方量计算精度的关系,当土石方量计算精度一定时,对于不同的场平面积、地形图比例尺、地形坡度、施工高度,应采用不同的方格边长,一般情况下,不宜在1:2000或更小比例尺图上进行,方格网边长不宜小于1m。  相似文献   

3.
This paper presents an approach for GIS integrating local participatory land management information used for regional planning, and contributing to a bottom-up approach to land use planning. In participatory planning, the integration between local and regional levels should facilitate the communication and co-operation among the parties at both levels, for an efficient use of available resources. For coherently linking these two levels it is necessary to transform the data produced at one level, in order to be usable by the other. This transformation consists of a spatial procedure, which allows scaling-up the local participatory rural appraisal (PRA) information for regional purposes and scaling down the regional information for local use, using a GIS. Such an integration procedure is presented and discussed using data from a case study in south-western Burkina Faso.  相似文献   

4.
Almost all engineering evacuation models define the objective as minimizing the time required to clear the region or total travel time, thus making an implicit assumption that who will or should evacuate is known. Conservatively evacuating everyone who may be affected may be the best strategy for a given storm, but there is a growing recognition that in some places that strategy is no longer viable and in any case, may not be the best alternative by itself. Here, we introduce a new bi-level optimization that reframes the decision more broadly. The upper level develops an evacuation plan that describes, as a hurricane approaches, who should stay and who should leave and when, so as to minimize both risk and travel time. The lower level is a dynamic user equilibrium (DUE) traffic assignment model. The model includes four novel features: (1) it refocuses the decision on the objectives of minimizing both risk and travel time; (2) it allows direct comparison of more alternatives, including for the first time, sheltering-in-place; (3) it uses a hurricane-scenario-based analysis that explicitly represents the critically important uncertainty in hurricane track, intensity, and speed; and (4) it includes a new DUE algorithm that is efficient enough for full-scale hurricane evacuation applications. The model can be used both to provide an evacuation plan and to evaluate a plan’s performance in terms of risk and travel time, assuming the plan is implemented and a specified hurricane scenario then actually occurs. We demonstrate the model with a full-scale case study for Eastern North Carolina.  相似文献   

5.
1:25万区域地质调查修测的核心任务是挖掘、利用前人资料和对前人资料的二次开发。在1:25万玉林市幅数字地质填图试点的过程中.总结出一套基于数字填图系统的前人地质资料利用与数据采集的工作方法。其工作流程和工作步骤可分为6个阶段:①前期准备阶段;②室内地质资料录八阶段;③野外数字地质调查阶段;④室内资料整理阶段;⑤图件编制阶段;⑥成果提交阶段。该工作方法与传统的地质调查方法相比,提高了地质调查的工作效率和质量,已基本上达到了在1:252万区调修测区推广应用的“实战性”要求。  相似文献   

6.
In many of the lesser developed areas of the world, regional development planning is increasingly important for meeting the needs of current and future inhabitants. Expansion of economic capability, infrastructure, and residential capacity requires significant investment, and so efforts to limit the negative effect of landslides and other natural hazards on these investments are crucial. Many of the newer approaches to identifying and mapping relative landslide susceptibility within a developing area are hindered by insufficient data in the places where it is most needed. An approach called matrix assessment was specifically designed for regional development planning where data may be limited. Its application produces a landslide-susceptibility map suitable for use with other planning data in a Geographical Information System (GIS) environment. Its development also encourages collecting basic landslide inventory data suitable for site-specific studies and for refining landslide hazard assessments in the future. This paper illustrates how matrix assessment methodology was applied to produce a landslide-susceptibility map for the Commonwealth of Dominica, an island nation in the eastern Caribbean, and how with a follow up study the relative landslide-susceptibility mapping was validated. A second Caribbean application on Jamaica demonstrates how this methodology can be applied in a more geologically complex setting. A validated approach to mapping landslide susceptibility which does not require extensive input data offers a significant benefit to planning in lesser developed parts of the world.  相似文献   

7.
Four variogram models for regional groundwater geochemical data are presented. These models were developed from an empirical study of the sample variograms for more than 10 elements in groundwaters from two geologic regions in the Plainview quandrangle, Texas. A procedure is given for the estimation of the variogram in the isotropic and anisotropic case. The variograms were found useful for quantifying the differences in spatial variability for elements within a geologic unit and for elements in different geologic units. Additionally, the variogram analysis enables assessment of the assumption of statistical independence of regional samples which is commonly used in many statistical procedures. The estimated variograms are used in computation of kriged estimates for the Plainview quadrangle data. The results indicate that an inverse distance weighting model was superior for prediction than simple kriging with the particular variograms used.  相似文献   

8.
区域水资源规划方案的优选过程通常是一个多属性、群决策过程。在对该领域研究现状综述的基础上,提出了多属性递阶群决策的概念,建立了6类数据的灰类白化函数,构建了包括基层A、专家层B和高级管理层C的3层群决策模型,并给出了具体的算法步骤,在EXCEL上编制了通用程序。实例计算结果表明,该模型真实地反映了水资源规划方案优选的过程,结论合理,求解思路清晰。  相似文献   

9.
Scattered data interpolation schemes using kriging and radial basis functions (RBFs) have the advantage of being meshless and dimensional independent; however, for the datasets having insufficient observations, RBFs have the advantage over geostatistical methods as the latter requires variogram study and statistical expertise. Moreover, RBFs can be used for scattered data interpolation with very good convergence, which makes them desirable for shape function interpolation in meshless methods for numerical solution of partial differential equations. For interpolation of large datasets, however, RBFs in their usual form, lead to solving an ill-conditioned system of equations, for which, a small error in the data can cause a significantly large error in the interpolated solution. In order to reduce this limitation, we propose a hybrid kernel by using the conventional Gaussian and a shape parameter independent cubic kernel. Global particle swarm optimization method has been used to analyze the optimal values of the shape parameter as well as the weight coefficients controlling the Gaussian and the cubic part in the hybridization. Through a series of numerical tests, we demonstrate that such hybridization stabilizes the interpolation scheme by yielding a far superior implementation compared to those obtained by using only the Gaussian or cubic kernels. The proposed kernel maintains the accuracy and stability at small shape parameter as well as relatively large degrees of freedom, which exhibit its potential for scattered data interpolation and intrigues its application in global as well as local meshless methods for numerical solution of PDEs.  相似文献   

10.
On the basis of study of fossil plants, the climate in southwestern Siberia in the Early Senonian was reconstructed to be warm temperate humid with the mean annual temperature of about 13°C. The CLAMP analysis (Climate Leaf Analysis Multivariate Program) was applied for the first time to Cretaceous floras of Western Siberia. The comparison results of climatic variables estimated show that the climate in Western Siberia in the Early Senonian was more humid and warmer than in Northeast Asia.  相似文献   

11.
12.
江西省燕山-喜马拉雅运动以块断作用为主,形成了一系列断裂隆起带和断陷盆地,白垩纪、早第三纪红层发育齐全.丹霞地貌主要发育于上白垩统紫红色含钙粗碎屑岩中,受盆缘断裂和中幼年河流控制,是晚第三纪以来新构造运动间歇性隆升,伴随着断裂切割、流水冲刷和风化剥蚀的产物.根据陆地卫星TM图像解译和野外实地调查,查明了全省共有丹霞地貌景观资源123处,其中新发现景点78处.丹霞地貌景观主要分布在该省周边丘陵低山区,明显受不同级别河流的流域控制,具带状分布规律,可划分出9个景观集中分布区域.赣东、赣东南丹霞地貌景观最为密集,结合红色旅游和客家文化特色,该区具有强劲的丹霞地貌旅游开发潜力.  相似文献   

13.
Consolidating measurement data for use by data models or in inter-comparison studies frequently requires transforming the data onto a common grid. Standard methods for interpolating multidimensional data are often not appropriate for data with non-homogenous dimensionality, and are hard to implement in a consistent manner for different datastreams. These challenges are increased when dealing with the automated procedures necessary for use with continuous, operational datastreams. In this paper we introduce a method of applying a series of one-dimensional transformations to merge data onto a common grid, examine the challenges of ensuring consistent application of data consolidation methods, present a framework for addressing those challenges, and describe the implementation of such a framework for the Atmospheric Radiation Measurement (ARM) program.  相似文献   

14.
区域化探数据处理的几种分形方法   总被引:20,自引:1,他引:20  
地球化学变量兼有随机性、确定性和区域结构性的特征,传统的数学方法难以精确地描述地球化学变量的空间分布规律,而新兴的分形几何是刻画空间不规则形体的一种比较有效的工具,且分维值可以表征空间不规则形体的确定性本质。基于分形原理,提出含量-总量法、空间分形插值法和分形趋势面法3种新的分形技术,应用于区域化探数据处理。在几个典型矿区应用后发现,上述分形方法不仅可以有效地模拟地球化学变量的空间分布特征,而且在保留原始有效异常信息的基础上可以更合理地区分地球化学变量的背景与异常,具有发现和强化弱异常信息的重要功效。  相似文献   

15.
16.
Present and future demand for natural resources has received increasing interest in local planning in Norway. Reliable geological data are a precondition for responsible management of these resources.

Available geological material, of all types, should be evaluated and compiled selectively in a form adapted for use by local planners not versed in the geosciences.

The Royal Norwegian Ministry for the Environment has initiated a project to establish a modelresource management plan in Ullensaker commune. The Geological Survey of Norway has developed a system for the presentation of geological data to be used for the management of geological resources like sand, gravel, rock aggregate and groundwater within Ullensaker commune.  相似文献   


17.
We present a web client-server service WEB-IS, which we have developed for remote analysis and visualization of seismic data consisting of both small magnitude events and large earthquakes. We show that the problem-solving environment (PSE) intended for prediction of large magnitude earthquakes can be based on this WEB-IS idea. The clustering schemes, feature generation, feature extraction techniques and rendering algorithms form a computational framework of this environment. On the other hand, easy and fast access both to the seismic data distributed among distant computing resources and to computational and visualization resources can be realized in a GRID framework. We discuss the usefulness of NaradaBrokering (iNtegrated Asynchronous Real-time Adaptive Distributed Architecture) as a middleware, allowing for flexibility and high throughput for remote visualization of geophysical data. The WEB-IS functionality was tested both on synthetic and the actual earthquake catalogs. We consider the application of similar methodology for tsunami alerts.  相似文献   

18.
以《1∶5 万数字地质图数据库试验研究》项目成果为基础,重点阐述了应用MAPGIS软件建立数字地质图数据库的工作方法、技术要点和先后步骤,简要介绍了计算机辅助制图与GIS的区别和空间数据库的应用。  相似文献   

19.
Dave Counsell  Graham Haughton   《Geoforum》2006,37(6):921-931
This paper focuses on sustainability appraisal as a key technique for pursuing the political goal of ‘sustainable development’ within English planning. We conclude that unlike many planning tools of the past which have sought to depoliticise decision making by using more ‘scientific’ techniques, the early experience of sustainability appraisal has instead repoliticised them, by highlighting where tensions exist but without providing solutions.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号