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291.
沉积过程的三维计算机模拟及其应用 总被引:1,自引:0,他引:1
利用模拟沉积、剥蚀和搬运过程的数学模型和基本算法,开发了模拟软件SSSP(simulating system of sedimentary processes)。该软件能够进行主要沉积环境的大规模剥蚀、搬运和沉积过程的复杂模拟,并可控制各种参数实时显示模拟结果,包括剖面图、沉积相图、等值线图、网格图和速度矢量图等。在已知沉积环境参数的情况下,利用SSSP再现盆地的沉积演化过程、沉积构型和沉积相分布,并给出了三角洲、河道和水下台阶沉积环境模拟实例。 相似文献
292.
孔隙型热储层的回灌过程中,由于物理堵塞、生物化学堵塞、悬浮物堵塞和气体堵塞,热储层的渗透性下降,回灌能力变弱.为了定量查明渗透系数的衰减,以辽南地区某回灌试验为例,使用Origin软件计算出研究区渗透系数衰减方程,在此基础上计算了回灌井灌压-时间关系曲线和回扬周期.研究表明,利用Origin软件求取渗透系数衰减方程具有... 相似文献
293.
Attribution analysis for water yield service based on the geographical detector method: A case study of the Hengduan Mountain region 总被引:1,自引:0,他引:1
Ecosystem services, which include water yield services, have been incorporated into decision processes of regional land use planning and sustainable development. Spatial pattern characteristics and identification of factors that influence water yield are the basis for decision making. However, there are limited studies on the driving mechanisms that affect the spatial heterogeneity of ecosystem services. In this study, we used the Hengduan Mountain region in southwest China, with obvious spatial heterogeneity, as the research site. The water yield module in the In VEST software was used to simulate the spatial distribution of water yield. Also, quantitative attribution analysis was conducted for various geomorphological and climatic zones in the Hengduan Mountain region by using the geographical detector method. Influencing factors, such as climate, topography, soil, vegetation type, and land use type and pattern, were taken into consideration for this analysis. Four key findings were obtained. First, water yield spatial heterogeneity is influenced most by climate-related factors, where precipitation and evapotranspiration are the dominant factors. Second, the relative importance of each impact factor to the water yield heterogeneity differs significantly by geomorphological and climatic zones. In flat areas, the influence of evapotranspiration is higher than that of precipitation. As relief increases, the importance of precipitation increases and eventually, it becomes the most influential factor. Evapotranspiration is the most influential factor in a plateau climate zone, while in the mid-subtropical zone, precipitation is the main controlling factor. Third, land use type is also an important driving force in flat areas. Thus, more attention should be paid to urbanization and land use planning, which involves land use changes, to mitigate the impact on water yield spatial pattern. The fourth finding was that a risk detector showed that Primarosol and Anthropogenic soil areas, shrub areas, and areas with slope 5° and 25°–35° should be recognized as water yield important zones, while the corresponding elevation values are different among different geomorphological and climatic zones. Therefore, the spatial heterogeneity and influencing factors in different zones should be fully con-sidered while planning the maintenance and protection of water yield services in the Hengduan Mountain region. 相似文献
294.
295.
A Double Solid Reactant Method was elaborated from a suggestion of Marini (Geological sequestration of carbon dioxide: Thermodynamics,
kinetics, and reaction path modeling. Developments in Geochemistry, Elsevier, Amsterdam, 2007) to simulate the release of
trace elements during the progressive dissolution of solid phases. The method is based on the definition, for each dissolving
solid, of both an entity whose thermodynamic and kinetic properties are known (either a pure mineral or a solid mixture) and
a special reactant, that is, a material of known stoichiometry and unknown thermodynamic and kinetic properties. The special
reactant is utilised to take into account the concentrations of trace elements in the dissolving solid phase. In this communication,
the influence of several trace elements on the ΔG
f
o, ΔG
r
o and log K of the minerals considered by Lelli et al. (Environ Geol, 2007) and Accornero and Marini (Geobasi, 2007a; Proceedings of
IMWA symposium, Cagliari, 27–31 May 2007b) was evaluated assuming ideal mixing in the solid state. These effects were found
to be negligible for albite and the leucite–latitic glass, limited for muscovites and chlorites, and slightly more important
for apatites. These influences become progressively higher with increasing concentration of trace elements in these minerals.
Based on these deviations in thermodynamic parameters, special reactants should not include oxide components with molar fractions
higher than 0.003.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
相似文献
Luigi MariniEmail: |
296.
297.
针对传统的建筑物建模方法需要大量人机交互操作,建模过程复杂和成本高的问题,该文提出一种参数化建筑物三维建模方法。首先,以高分辨率遥感影像和建筑物立面影像作为数据源,在遥感和GIS软件平台的支持下,提取建筑物的底面边界、高度、楼层数、层高和屋顶类型等空间数据和属性数据,并将其保存至GIS空间数据库。其次,提出基于拉伸、拆分、添加结构面过程的建筑物主体结构建模方案,并设计了模型自动生成算法。进一步,采用Ruby面向对象语言,通过调用SketchUp平台的应用程序接口函数,结合编程实现了建筑物的自动化建模。最后,开发了建筑物参数化建模插件。实际建模实验成果表明:该方法能够显著降低建模人员劳动强度,提高建模效率。 相似文献
298.
产业转型背景下创业区位选择和集群空间演化 总被引:5,自引:4,他引:1
以广州软件和信息技术产业集群为案例,分析产业范式转变背景下地方创业区位选择对产业集群空间演化的影响。结果显示:初始资源富集和政策环境导向使特定空间成为创业的优势区位,早期第一代创业企业在其中集聚发展形成集群雏形,并在关系网络和区域认同作用下形成产业集群空间核心区。第二代创业企业在产业转型契机下选择开拓缝隙市场,新的区位诉求由此产生并作用在集群的空间演化上。总的来说,产业转型期同时也是集群空间转变的关键时期,创业企业通过区位选择可以改变集群的空间形态和层次。 相似文献
299.
GIS组件分类与检索技术的研究和应用 总被引:2,自引:0,他引:2
讨论了组件分类和匹配原理,并对签名匹配法进行了研究,把它作为从已知的组件中获取可重用组件的方法,最后提出了在国土信息管理领域中GIS组件的解决方案。 相似文献
300.
地理信息系统开发方法的演进 总被引:7,自引:0,他引:7
随着计算机科学和软件工程技术的进步 ,GIS软件工程方法在不断地演进 ,越来越适合于GIS的开发。文中介绍和回顾了GIS在自身的发展过程中使用的一些软件工程方法 ,并初步探讨了为GIS项目选用软件开发方法的问题。 相似文献