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Interrelations between socio-economic development and environmental quality: a simulation integrating system dynamics models with GIS 总被引:1,自引:0,他引:1
YU Jie BIAN Fuling PETERSON Jim LI Pingxiang 《地球空间信息科学学报》2005,8(3):176-182
System dynamics (SD) theory has long been deployed in modeling complex non-linear interrelationships but, so far it has not been common to do the kind of modeling in support of bringing environmental sustainability policies to practice. This is largely because the challenge of including spatial data has not yet been well met. Potential for adoption of SD and GIS methods in combination is exemplified with the results of a decision-support exercise designed for simulation and prediction of the dynamic inter-relationships between socio-economic development and environmental quality for the “Wen, Pi, Du” county in Sichuan province, southwestern China. 相似文献
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URTK: undifferenced network RTK positioning 总被引:3,自引:1,他引:2
Standard network RTK has been widely used since it was proposed in the mid-1990s. Rovers can obtain high-precision estimates of position by resolving double-differenced (DD) ambiguities. The focus of this study is a new undifferenced network RTK method, abbreviated as URTK hereafter, based on undifferenced (UD) observation corrections whose single-differenced (SD) ambiguities between satellites can be resolved in several seconds. The tools for studying the real-time realization of the new method are our developments of logical schemes that have the capability for the real-time modeling of a reference network and the instantaneous resolution of SD ionosphere-free (IF) ambiguities at a single station. This research demonstrates the validity of modeling regional UD-unmodeled errors on the ground and examines the maximum differences when compared to modeling the errors using ionospheric pierce points (IPP). With data collected at 48 stations from a CORS network in Shanxi Province (SXCORS) in China through May 21, 2010, the efficiency of the presented real-time strategies is validated using IGS final products in a postprocessing mode. The results verify that more than 83 % of SD wide-lane (WL) ambiguity can be fixed with 5 s of observation data, and the average resolution time of all the WL tests is 4.96 s. More than 80 % of SD L1 ambiguity can be fixed within 5 s, and the average resolution time is only 6.66 s. Rovers could gain rapidly centimeter-level absolute positioning service, comparable to standard network RTK. In addition, the URTK method transforms the fixed DD-ambiguities of the reference network into UD-ambiguities, and it does not need to set the base station and base satellite. Since the UD-corrections are modeled for each common visible satellite, it breaks down the connections between stations and satellites of the DD-corrections in the current network RTK. The UD-corrections can be broadcast by the base station and automatically selected and optimized by a rover during the real-time kinematic processing, thus avoiding ambiguity in reinitialization due to the change of reference, so it should be very flexible and useful for a wide range of applications. 相似文献
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地理科学对地理环境系统的研究是以地理信息获取的研究为基础的,后者制约着地理科学研究方法的进步,并影响了整个地理科学的发展水平。现代遥感技术辅之以系统科学等一系列先进的科学理论和技术,在地理环境系统研究中的成功应用,形成遥感技术的一个重要应用分支学科——环境遥感,其作为地理科学研究技术工具学科的地位逐渐确立。 环境遥感研究的实质表现为三个方面:(1)地理环境系统中电磁相互作用关系的充分利用;(2)遥感信息机制研究支持下的地理环境信息处理系统的结构优化;(3)地理环境系统综合分析过程标准化的实现。 环境遥感的学科地位体现为双重特征,即重要的遥感应用分支和现代地理科学研究新的技术方法。由于横跨信息科学和地理科学两大领域,环境遥感充分体现出其综合性、交叉性的学科特点。环境遥感和常规的地理研究方法,分别着重于对地理环境系统中能量信息系统或物质信息系统的考察,两者在某些方面,至少在今天看来是不能互相取代的。但是,环境遥感依靠其技术系统的不断完善、综合分析功能的加强以及对一系列非能量信息的参照和相关分析(如信息复合技术)而在地理环境系统研究的很多领域显示出独特的优越性。 同时,由于科学认识和科学技术水平的整体制约,以及学科本身的固有特性,环境遥感研究仍 相似文献
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国家环境遥感监测体系研究与实现 总被引:3,自引:0,他引:3
随着国家空间基础设施的建设和发展,中国遥感监测体系研究与建设取得了重大突破,从无到有形成了国家环境遥感监测能力,并业务化实现了主要环境遥感监测要素产品的生产与服务,为新时期环境管理工作提供了有力支撑。在分析国内外环境遥感发展及中国环境遥感监测需求的基础上,阐述了中国环境监测体系建设的必要性,研究了国家环境遥感监测体系的建立与业务化运行,提出了中国环境遥感监测体系发展思路与下一步重点任务。 相似文献
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Land use and land cover change (LULCC) is a widely researched topic in related studies. A number of models have been established to simulate LULCC patterns. However, the integration of the system dynamic (SD) and the cellular automata (CA) model have been rarely employed in LULCC simulations, although it allows for combining the advantages of each approach and therefore improving the simulation accuracy. In this study, we integrated an SD model and a CA model to predict LULCC under three future development scenarios in Northern Shanxi province of China, a typical agro-pastoral transitional zone. The results indicated that our integrated approach represented the impacts of natural and socioeconomic factors on LULCC well, and could accurately simulate the magnitude and spatial pattern of LULCC. The modeling scenarios illustrated that different development pathways would lead to various LULCC patterns. This study demonstrated the advantages of the integration approach for simulating LULCC and suggests that LULCC is affected to a large degree by natural and socioeconomic factors. 相似文献
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详细阐述了应用全国1km土地利用/覆盖25层分层栅格数据合并生成单层土地利用/覆盖图的方法。通过对初始合成结果的归类、合并和空间平滑,有效减少了图像上像元分布零散的情况,突出了土地利用的空间总体分布格局。具体应用表明,这种处理方法得到的土地利用/覆盖图能够满足水文、地学分析的要求。 相似文献
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基于GIS-SD的大连湾水污染时空模拟与调控策略研究 总被引:20,自引:0,他引:20
大连泫可持续发展的矛盾是一个动态现象,同时这些矛盾也涉及到空间因子(例如,污染物浓度分布与环境功能区划等)。为了探讨和模拟各种发展方案(不同的经济增长和城市化)的矛盾机理,将系统动力学(SD)方法和地理信息系统(GIS)方法结合起来,提出了一个新的可操作的GIS-SD结合的概念框架,建立了大连湾水污染与控制系统模型,并进行了时空模拟和调控策略研究,模拟了该区域的不同增长计划(方案)对海域环境环境质 相似文献
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Gholam Reza Fallahi Andrew U. Frank Mohammad Saadi Mesgari Abbas Rajabifard 《International Journal of Applied Earth Observation and Geoinformation》2008
Service-oriented architecture in a distributed computing environment, with loosely coupled geo-services is a new approach for using GIS services in environmental modeling. The messages exchanged must follow a set of standard protocols which support syntactic interoperability, but do not address application semantics. 相似文献
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在全国第二次湖泊资源调查成果的基础上,将水环境基础资料、遥感信息、水文气象信息、水环境模型等进行综合管理,利用ENVI/IDL二次开发语言对全国重点湖泊建立了专业遥感模型,探索建立了湖泊水环境卫星遥感监测系统。以太湖为示范区对系统进行应用,制作了水环境参数专题产品。 相似文献
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空间数据质量在不同的应用领域有不同的特征,在一种应用中适用的数据不一定适用于另外一种应用。位置数据在交通领域的应用非常广泛,包括交通事故分析、交通需求量建模、基础设施管理、交通政策分析、商用车辆使用、交通线路使用及智能化交通运输系统,且有些应用对质量问题更为敏感。因此,建议空间数据质量报告中应附带所有空间数据的转换或使用。如果不附带属性数据,那么空间数据对交通应用的意义将很小或几乎没有。 相似文献
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大规模三维城市模型在城市规划与管理、环境模拟、应急响应、导航、虚拟旅游以及其他科学和大众应用方面的需求越来越高。在过去的20年中,通过多学科的共同努力,大规模城市三维建模已经取得了可观的成就。本文全面总结和讨论了三维城市建模在数据源、建模方法和平台、模型表达和互操作等方面的新技术和新进展,并描述了世界范围内开放城市模型的几个代表性示例。在日益多样化的数据,先进但价格可承受的技术以及不断增长的公共和科学需求的推动下,三维城市建模正在加速实现自动化、细致化、语义化、标准化、一体化和大众化。 相似文献
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Several complex dynamic spatial systems are operating on the global scale. Their representation with existing geosimulation models is limited to planar level and do not consider the curvature of the Earth's surface. Thus, the objective of this study is to propose and develop a spherical geographic automata (SGA) modeling approach to represent and simulate dynamic spatial processes at the global level. The proposed SGA model is implemented for three case studies including simulations of: (1) Game of Life as population dynamics; (2) urban land-use growth; and (3) deforestation all operating on the spherical Earth's surface. Simulation results indicate that the proposed SGA modeling approach can represent spatial processes such as expansion and shrinkage dynamics on the Earth's surface. The proposed approach has the potential to be adopted to represent different complex systems such as ecological, epidemiological, socioeconomic, and Earth systems processes to support environmental management and policymaking at the global level. 相似文献
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大气折射的映射函数与神经网络拟合比较分析 总被引:1,自引:0,他引:1
首先介绍映射函数和神经网络模拟方法在大气折射研究领域中的应用情况,总结映射函数的基本形式,分析BPNN的基本原理,进而研究了基本映射函数的BPNN变换。最终利用普尔科沃大气折射表这一数据平台与MATLAB7中的神经网络工具箱,建立与映射函数对应的BPNN模型,对普尔科沃大气折射表进行BPNN模拟。与相关文献的映射函数模拟进行比较分析:BPNN的模拟精度是4阶分式映射函数的2倍,不仅证明大气折射的映射函数模拟存在较大的拟合残差,而且表明BPNN对大气折射的非线性拟合优于映射函数,同时也为BPNN的隐层神经元具备挖掘高阶隐含信息提供了一个研究实例。 相似文献
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Shishir Gaur B.R. Chahar Didier Graillot 《International Journal of Applied Earth Observation and Geoinformation》2011
A methodology for groundwater evaluation has been developed by the combined use of numerical model and spatial modeling using GIS. The developed methodology has been applied on the sub-basin of the Banganga River, India. Initially, the groundwater potential zones have been delineated by spatial modeling. Different thematic maps of the basin like geology, geomorphology, soil, drainage, slope factor and landuse/landcover have been used to identify the groundwater potential zones. Further, the groundwater flow model for the study area has been developed in the MODFLOW. The groundwater flow vector map has been developed and superimposed on the potential zone map to validate the results of spatial modeling. Finally, the different scenarios have been conceptualized by varying the discharge of the wells and purposing the location for new rainwater harvesting structures. Results reveal that increasing the discharge of the wells in the potential zones put less stress on the aquifer. The suggested locations of rainwater harvesting structures also help to reduce the overall decline of groundwater in the area. The hydrological and spatial modeling presented in this study is highly useful for the evaluation of groundwater resources and for deciding the location of rainwater harvesting structures in semi-arid regions. 相似文献