937 resultados para Gis


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安全环境是人类赖以生存的基础,天然放射性辐射环境是人类生存环境的重要组成部分,放射性物质存在于各类物质中,包括空气、水源和土壤等。放射性物质的辐射对环境的影响往往被人们所忽视,但又是最危险的环境影响因素。为了生存和健康不仅需要了解重金属和有机物污染,而且需要了解辐射污染。 天然放射性辐射环境与该区域内的地质环境密切相关。青岛地区燕山期岩浆活动频繁,形成了以钾长花岗岩和二长花岗岩为主的大规模侵入岩体,大多数母岩为富含铀、钍的花岗岩。本论文选择青岛地区做为放射性的研究区,该花岗岩地区与放射性核素的辐射强度的关系具有典型的代表性。 论文在大量密集测量地表岩石、土壤γ总量、土壤中238U、232Th 、40K放射性核素的含量基础上,分析了天然放射性辐射环境与该区域内的地质环境. 分析了环境中氡的来源及迁移机制,给出了氡的运移理论模型,指出了环境中氡的危害及其土壤中的分布与地质环境的关系。分别从内照射和外照射的角度,将土壤中238U (226Ra) 、232Th 、40K放射性核素的比活度、γ能量谱、环境中的氡浓度和直接测量空气中的吸收剂量率相结合,首次对青岛地区的辐射环境进行了研究和评价,可为奥运和青岛市长远发展提供科学保障。 结果表明研究区内土壤中的238U含量低于全国及世界平均值,土壤中232Th含量分别是全国和世界均值含量的1.1和1.5倍, 土壤中40K含量分别是全国和世界均值含量的2.43和2.44倍,因此空气中的吸收剂量率高于全国(81.5nGy•h-1)和世界(80 nGy•h-1)约1.2倍。通过能谱估算的空气吸收剂量率与实际测量值近似相等。研究区的年有效剂量为0.83 mSv,低于世界平均年有效外部照射的剂量限值1.0mSv,外照射指数和内照射指数均小于1,该区的等效镭浓度Raeq均值为197 Bq•kg-1,低于建议最大容许值370 Bq•kg-1,基于以上的各类指标均在世界均值或容许值范围内,可以认为该区的外照射水平属于安全辐射范畴。 222Rn浓度对人体内部照射具有举足轻重的地位,也是评价辐射环境质量的关键所在。本文采用经典的氡在空气中的扩散和对流的理论模式,通过研究区内的土壤中铀的含量推算出离地面1米高的空气中的氡的浓度,并且分析了土壤中的氡浓度与土壤中的放射性核素U、Th、K的含量的关系。研究区的土壤氡浓度总体平均值为5887Bq/m3,与全球土壤氡浓度的平均值7400 Bq/m3相比属于土壤氡浓度正常地区。由于青岛市区土壤覆盖层很薄,地表储气条件较差,造成土壤氡逸散。因此除区内土壤氡浓度几处偏高区以的其他区域,甚至断裂带上他和其他区域的土壤氡浓度也普遍偏低。通过计算可以得出青岛市区大气中氡浓度所导致的居民室外吸入氡子体所产生的年均人有效剂量估算结果是0.94mSv/a。这与联合国辐射防护委员会公布世界平均本底值1.2mSv/a相比,此值在正常范围内。 这个地区虽然大面积出露富含放射性物质的花岗岩,由花岗岩风化形成的土壤中放射性核素含量(钍、钾)也较高,但是因为铀含量不高,另外本区临海,一年四季的风速较大,因此本地区室外和室内空气中氡浓度不高。 综上可以得出结论:本区的辐射环境属于安全区域,适于人类生活。 本论文研究成果和创新点有:首次在大量密集测量的基础上,系统地对青岛地区的辐射环境进行了研究和评价;在数据采集方面,采用直接就地测量,跟其他调查方法比,采样密度大,数据量大。从研究方法方面,本文从外照射和内照射的角度,采用了多指标相结合的综合方式来评价本区的辐射环境质量,详实可信;引入GIS技术,和放射性评价相结合,较为系统深入地探讨了放射性核素和氡浓度的分布特征及其与岩性的关系。

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黄河在自然和人为因素影响下,决口、改道频繁,1996年人工改道至清8出汊入海,使人工干预河口演变、延长河口流路使用年限成为可能。伴随着黄河入海水沙条件的变化,河海动力状况也将发生相应的改变,入海泥沙在河口的输移、沉积分布和三角洲海岸的形态必将表现出新的特征。基于此,本文依据现场水文泥沙观测资料、遥感影像和黄河口滨海区水深数据等,借助遥感图像处理技术、GIS空间分析功能和河口泥沙异重流力学计算,分析了黄河口清8出汊新河口海岸线的动态变化、河口泥沙异重流的时空演变特征及其对河口沉积的影响和清水沟流路新老口门水下三角洲的冲淤变化特征。 结果表明,河口改道初期,因水沙条件和河道的影响,河口淤积速度较快,随后几年因入海水沙逐渐减少和下游河段出现长期断流,黄河三角洲出现造陆负增长,到1999年人工统一调水后,一段时间内基本维持了口门的淤蚀动态平衡。但近几年来,河口周围又持续遭受冲刷,近岸海滩侵蚀严重。至2000年新河口泥沙净淤积10.28亿t,小于径流来沙量。由于新口门河道北偏转,受两侧潮流的作用,使得泥沙大部分淤积在口门前方,部分向河口两侧输移,且向北输移量大于向南,入海泥沙在河口沉积的空间分布上存在不均匀性。 入海泥沙以异重流的形式运移较频繁,泥沙异重流的空间分布与水下三角洲泥沙堆积体、河口沙嘴的形态存在明显相关,1996年黄河清8出汊以来,泥沙异重流的发生演变、与潮流周期的关系,以及流速的变化都表现出了新的特征。

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利用1987和2001年TM卫星遥感数据,在GIS的支持下对海北站土地覆盖变化进行了监测,14年来该区耕地面积增加迅速,高覆盖天然草地面积减少,中、低覆盖天然草地面积增加,湖泊、湿地萎缩,裸岩、沙地、裸土面积扩张,荒漠化程度加剧。

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使用循环采样设计方案,对海北沼泽化湿地生态系统涡度相关通量观测塔的通量贡献区内叶面积指数进行了实地调查.根据样方叶面积指数的实地测量值和样方的GPS空间定位信息,利用空间插值方法绘制了通量贡献区内的叶面积指数空间分布图.并基于数字摄影与地理信息系统技术,提出了一种测量速度快、计算精度高、适合多种植物叶片叶面积测量的新方法.该方法在ArcGIS的GRID模块下对叶片图像进行格式转化和重新采样处理,使用自行编写的色阶诊断程序提取图像中叶片的叶面积.研究结果表明:此种方法叶面积测量结果与LI-3000A叶面积仪所测的结果具有很好的吻合性,两者的线性回归方程决定系数R~2为0.98,叶面积的测量精度完全可以达到实际应用中的测量要求.

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在青藏公路与铁路沿途区域,利用1981年至2001年的8km分辨率PathfinderNOAA/NDVI数据,基于每个象元变化的年植被峰值计算进行了像元水平的线性趋势分析,并运用地理信息系统(GIS)软件研究了区域植被覆盖的空间分布和动态变化特征.主要结论:①在研究区内,反映植被覆盖的NDVI值在空间上呈现出两端高中间低的态势,依次是农作区和森林区>高寒草甸>高寒草原>荒漠草原;②20年间,研究区植被覆盖程度变化总体趋于稳定,覆盖程度呈减少趋势的区域明显高于增加的区域,植被覆盖程度增减因区域而异;植被覆盖程度增加和显著减少地区主要分布在农作区和高寒草甸区,轻微减少地区主要分布在高寒草原和荒漠草原区;③植被覆盖变化程度在拉萨河谷地、湟水谷地和黄河流域等人类活动比较频繁的区域增减趋势比较明显;而在可可西里地区等人类活动比较少的区域变化轻微.

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There is a need for methodology to warm open-field plots in order to study the likely effects of global warming on ecosystems in the future. Herein, we describe the development of arrays of more powerful and efficient infrared heaters with ceramic heating elements. By tilting the heaters at 45 degrees from horizontal and combining six of them in a hexagonal array, good uniformity of warming was achieved across 3-m-diameter plots. Moreover, there do not appear to be obstacles (other than financial) to scaling to larger plots. The efficiency [eta(h) (%); thermal radiation out per electrical energy in] of these heaters was higher than that of the heaters used in most previous infrared heater experiments and can be described by: eta(h) = 10 + 25exp(-0.17 u), where u is wind speed at 2 m height (m s(-1)). Graphs are presented to estimate operating costs from degrees of warming, two types of plant canopy, and site windiness. Four such arrays were deployed over plots of grass at Haibei, Qinghai, China and another at Cheyenne, Wyoming, USA, along with corresponding reference plots with dummy heaters. Proportional integral derivative systems with infrared thermometers to sense canopy temperatures of the heated and reference plots were used to control the heater outputs. Over month-long periods at both sites, about 75% of canopy temperature observations were within 0.5 degrees C of the set-point temperature differences between heated and reference plots. Electrical power consumption per 3-m-diameter plot averaged 58 and 80 kW h day(-1) for Haibei and Cheyenne, respectively. However, the desired temperature differences were set lower at Haibei (1.2 degrees C daytime, 1.7 degrees C night) than Cheyenne (1.5 degrees C daytime, 3.0 degrees C night), and Cheyenne is a windier site. Thus, we conclude that these hexagonal arrays of ceramic infrared heaters can be a successful temperature free-air-controlled enhancement (T-FACE) system for warming ecosystem field plots.

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In the paper through extensive study and design, the technical plan for establishing the exploration database center is made to combine imported and self developed techniques. By research and repeated experiment a modern database center has been set up with its hardware and network having advanced performance, its system well configured, its data store and management complete, and its data support being fast and direct. Through study on the theory, method and model of decision an exploration decision assistant schema is designed with one decision plan of well location decision support system being evaluated and put into action. 1. Study on the establishment of Shengli exploration database center Research is made on the hardware configuration of the database center including its workstations and all connected hardware and system. The hardware of the database center is formed by connecting workstations, microcomputer workstations, disk arrays, and those equipments used for seismic processing and interpretation. Research on the data store and management includes the analysis of the contents to be managed, data flow, data standard, data QC, data backup and restore policy, optimization of database system. A reasonable data management regulation and workflow is made and the scientific exploration data management system is created. Data load is done by working out a schedule firstly and at last 200 more projects of seismic surveys has been loaded amount to 25TB. 2. Exploration work support system and its application Seismic data processing system support has the following features, automatic extraction of seismic attributes, GIS navigation, data order, extraction of any sized data cube, pseudo huge capacity disk array, standard output exchange format etc. The prestack data can be accessed by the processing system or data can be transferred to other processing system through standard exchange format. For supporting seismic interpretation system the following features exist such as auto scan and store of interpretation result, internal data quality control etc. the interpretation system is connected directly with database center to get real time support of seismic data, formation data and well data. Comprehensive geological study support is done through intranet with the ability to query or display data graphically on the navigation system under some geological constraints. Production management support system is mainly used to collect, analyze and display production data with its core technology on the controlled data collection and creation of multiple standard forms. 3. exploration decision support system design By classification of workflow and data flow of all the exploration stages and study on decision theory and method, target of each decision step, decision model and requirement, three concept models has been formed for the Shengli exploration decision support system including the exploration distribution support system, the well location support system and production management support system. the well location decision support system has passed evaluation and been put into action. 4. Technical advance Hardware and software match with high performance for the database center. By combining parallel computer system, database server, huge capacity ATL, disk array, network and firewall together to create the first exploration database center in China with reasonable configuration, high performance and able to manage the whole data sets of exploration. Huge exploration data management technology is formed where exploration data standards and management regulations are made to guarantee data quality, safety and security. Multifunction query and support system for comprehensive exploration information support. It includes support system for geological study, seismic processing and interpretation and production management. In the system a lot of new database and computer technology have been used to provide real time information support for exploration work. Finally is the design of Shengli exploration decision support system. 5. Application and benefit Data storage has reached the amount of 25TB with thousand of users in Shengli oil field to access data to improve work efficiency multiple times. The technology has also been applied by many other units of SINOPEC. Its application of providing data to a project named Exploration achievements and Evaluation of Favorable Targets in Hekou Area shortened the data preparation period from 30 days to 2 days, enriching data abundance 15 percent and getting information support from the database center perfectly. Its application to provide former processed result for a project named Pre-stack depth migration in Guxi fracture zone reduced the amount of repeated process and shortened work period of one month and improved processing precision and quality, saving capital investment of data processing of 30 million yuan. It application by providing project database automatically in project named Geological and seismic study of southern slope zone of Dongying Sag shortened data preparation time so that researchers have more time to do research, thus to improve interpretation precision and quality.

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The Jinchuan Nickel Mine is the largest underground mine with cut-and-fill mining in China. It is very difficult to be exploited for very low safety stability of rock mass caused by complex geological conditions, developed faults, cracked rock mass and high stress. In this paper, the laws of rock mass movement、mechanics of shaft deformation and destroy were analyzed based on the collection of date, the detailed field engineering investigations, ground movement monitoring by GPS, theoretical analysis and numerical simulation. According to the GPS monitoring result of ground surface movement, there are different ground movement characteristics among the three Mine area of Jinchuan Nickel Mine. In No. 2 Mine area, the ground movement funnel with apparent asymmetry is developing, the influence scope is larger in the up faulted block than in the down faulted block, and the centre of ground movement is moving along the up faulted block direction with increasing depth of mining. Moreover, the tunnels in the corresponding area with the centre of ground movement are damaged seriously. In Longshou Mine area, the ground movement funnel is also developing, but the moving path and the nonlinear characters are more sophisticated because of the long-term effects of open excavating and the effects of underground mining together. In No. 3 Mine area, the underground mining impact on surface is not serious for the time of mining activity is not for long, but the ground movement funnel is also forming now. The underground mining has caused widespread land subsidence in Jinchuan Nickel Mine area, but the phenomena of surface raise appeared in some partial areas of Longshou Mine area and No. 3 Mine area. Analysis proved that the reason for the open pit bottom raise is the slope deformation activation caused by the excavation from open pit into underground mine; and that the raise of surface in No.3 Mine area is caused by the effect of elastic foundation due to underground mining. Although the GPS Monitoring results show the amount of subsidence is increasing constantly, the subsidence rate has a descending tendency with fluctuation in Jinchuan No. 2 Mine area. The subsidence rate curve is a time function and exists an extreme point, the rate increasing before extreme point and decreasing after the extreme point ,but the scale of decreasing rate will be very small after the rate decreasing up to a certain degree, moreover, the characteristics is different among different areas, which have some relation with the distance to the mining section and the dip of the ore body. ArcView is GIS software, which we adopted as a development platform, and made secondary development by its development language “avenue”, through which we developed a ground movement analysis and forecast System for Jinchuan Nickel Mine, which contain three modules : management of ground movement information; analysis and evaluation of ground movement; and ground movement forecast. In the module of evaluation, using the technique of MATLAB6.5 program with VB6.0, the system can achieve the ANN prediction model for GPS monitoring data, data preparation results analysis and model integrated was realized by Avenue programming. Finally, the author analyzed the mechanical of deformation and destroy of the No. 14 shaft, and its repair and artificial-support effectiveness also given detailed demonstration in various aspect. The result showed that the reason for the destroy of No. 14 shaft is underground mining, and being the case, the destroy of the shaft also has its special features, which mainly contains forked stress contour for mining steep ore and fault effect caused by mining activities. The repair and artificial-support played some restrictions on the rock mass movement and deformation, but did not show a strong or marked effect. With the increasing of mining depth and large-scale, the closure rock of the shaft will still deformed, even be destroyed.

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Groundwater basin is important for water supply in northern China. The paper took the Jingsheng Basin in Lingshi County, Shanxi Province as a case to study the basin groundwater system by numerical modeling. The hydrogeological characteristics were analysed basing on the field investigation, and a three-dimensional groundwater flow model was established to describe the groundwater flow system in the Jingsheng groundwater basin. The boundary of the model was determined by using geophysics and GIS data, and the lumped parameter model of runoff was used to depict the transform between the surface water and groundwater, and the groundwater dating data was used to calibrate the model. All these methods were used to improve the model. The Software Visual MODFLOW 2000 was applied to set up the numerical groundwater flow model. The groundwater flow pattern in the average year, the high-water year and the low-water year were simulated respectively by the model. Some new cognition to the groundwater movement in Jingsheng Basin was obtained in the paper. The difficult problems were resolved when using the conventional and theoretical analysis to forecast and appraise the exploitation of the groundwater, and supplies the instructional technology base for the reasonable exploitation and optimization collocation. The numerical model will improve evaluation of the basin groundwater resources.

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On the issue of geological hazard evaluation(GHE), taking remote sensing and GIS systems as experimental environment, assisting with some programming development, this thesis combines multi-knowledges of geo-hazard mechanism, statistic learning, remote sensing (RS), high-spectral recognition, spatial analysis, digital photogrammetry as well as mineralogy, and selects geo-hazard samples from Hong Kong and Three Parallel River region as experimental data, to study two kinds of core questions of GHE, geo-hazard information acquiring and evaluation model. In the aspect of landslide information acquiring by RS, three detailed topics are presented, image enhance for visual interpretation, automatic recognition of landslide as well as quantitative mineral mapping. As to the evaluation model, the latest and powerful data mining method, support vector machine (SVM), is introduced to GHE field, and a serious of comparing experiments are carried out to verify its feasibility and efficiency. Furthermore, this paper proposes a method to forecast the distribution of landslides if rainfall in future is known baseing on historical rainfall and corresponding landslide susceptibility map. The details are as following: (a) Remote sensing image enhancing methods for geo-hazard visual interpretation. The effect of visual interpretation is determined by RS data and image enhancing method, for which the most effective and regular technique is image merge between high-spatial image and multi-spectral image, but there are few researches concerning the merging methods of geo-hazard recognition. By the comparing experimental of six mainstream merging methods and combination of different remote sensing data source, this thesis presents merits of each method ,and qualitatively analyzes the effect of spatial resolution, spectral resolution and time phase on merging image. (b) Automatic recognition of shallow landslide by RS image. The inventory of landslide is the base of landslide forecast and landslide study. If persistent collecting of landslide events, updating the geo-hazard inventory in time, and promoting prediction model incessantly, the accuracy of forecast would be boosted step by step. RS technique is a feasible method to obtain landslide information, which is determined by the feature of geo-hazard distribution. An automatic hierarchical approach is proposed to identify shallow landslides in vegetable region by the combination of multi-spectral RS imagery and DEM derivatives, and the experiment is also drilled to inspect its efficiency. (c) Hazard-causing factors obtaining. Accurate environmental factors are the key to analyze and predict the risk of regional geological hazard. As to predict huge debris flow, the main challenge is still to determine the startup material and its volume in debris flow source region. Exerting the merits of various RS technique, this thesis presents the methods to obtain two important hazard-causing factors, DEM and alteration mineral, and through spatial analysis, finds the relationship between hydrothermal clay alteration minerals and geo-hazards in the arid-hot valleys of Three Parallel Rivers region. (d) Applying support vector machine (SVM) to landslide susceptibility mapping. Introduce the latest and powerful statistical learning theory, SVM, to RGHE. SVM that proved an efficient statistic learning method can deal with two-class and one-class samples, with feature avoiding produce ‘pseudo’ samples. 55 years historical samples in a natural terrain of Hong Kong are used to assess this method, whose susceptibility maps obtained by one-class SVM and two-class SVM are compared to that obtained by logistic regression method. It can conclude that two-class SVM possesses better prediction efficiency than logistic regression and one-class SVM. However, one-class SVM, only requires failed cases, has an advantage over the other two methods as only "failed" case information is usually available in landslide susceptibility mapping. (e) Predicting the distribution of rainfall-induced landslides by time-series analysis. Rainfall is the most dominating factor to bring in landslides. More than 90% losing and casualty by landslides is introduced by rainfall, so predicting landslide sites under certain rainfall is an important geological evaluating issue. With full considering the contribution of stable factors (landslide susceptibility map) and dynamic factors (rainfall), the time-series linear regression analysis between rainfall and landslide risk mapis presented, and experiments based on true samples prove that this method is perfect in natural region of Hong Kong. The following 4 practicable or original findings are obtained: 1) The RS ways to enhance geo-hazards image, automatic recognize shallow landslides, obtain DEM and mineral are studied, and the detailed operating steps are given through examples. The conclusion is practical strongly. 2) The explorative researching about relationship between geo-hazards and alteration mineral in arid-hot valley of Jinshajiang river is presented. Based on standard USGS mineral spectrum, the distribution of hydrothermal alteration mineral is mapped by SAM method. Through statistic analysis between debris flows and hazard-causing factors, the strong correlation between debris flows and clay minerals is found and validated. 3) Applying SVM theory (especially one-class SVM theory) to the landslide susceptibility mapping and system evaluation for its performance is also carried out, which proves that advantages of SVM in this field. 4) Establishing time-serial prediction method for rainfall induced landslide distribution. In a natural study area, the distribution of landslides induced by a storm is predicted successfully under a real maximum 24h rainfall based on the regression between 4 historical storms and corresponding landslides.

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As a typical geological and environmental hazard, landslide has been causing more and more property and life losses. However, to predict its accurate occurring time is very difficult or even impossible due to landslide's complex nature. It has been realized that it is not a good solution to spend a lot of money to treat with and prevent landslide. The research trend is to study landslide's spatial distribution and predict its potential hazard zone under certain region and certain conditions. GIS(Geographical Information System) is a power tools for data management, spatial analysis based on reasonable spatial models and visualization. It is new and potential study field to do landslide hazard analysis and prediction based on GIS. This paper systematically studies the theory and methods for GIS based landslide hazard analysis. On the basis of project "Mountainous hazard study-landslide and debris flows" supported by Chinese Academy of Sciences and the former study foundation, this paper carries out model research, application, verification and model result analysis. The occurrence of landslide has its triggering factors. Landslide has its special landform and topographical feature which can be identify from field work and remote sensing image (aerial photo). Historical record of landslide is the key to predict the future behaviors of landslide. These are bases for landslide spatial data base construction. Based on the plenty of literatures reviews, the concept framework of model integration and unit combinations is formed. Two types of model, CF multiple regression model and landslide stability and hydrological distribution coupled model are bought forward. CF multiple regression model comes form statistics and possibility theory based on data. Data itself contains the uncertainty and random nature of landslide hazard, so it can be seen as a good method to study and understand landslide's complex feature and mechanics. CF multiple regression model integrates CF (landslide Certainty Factor) and multiple regression prediction model. CF can easily treat with the problems of data quantifying and combination of heteroecious data types. The combination of CF can assist to determine key landslide triggering factors which are then inputted into multiple regression model. CF regression model can provide better prediction results than traditional model. The process of landslide can be described and modeled by suitable physical and mechanical model. Landslide stability and hydrological distribution coupled model is such a physical deterministic model that can be easily used for landslide hazard analysis and prediction. It couples the general limit equilibrium method and hydrological distribution model based on DEM, and can be used as a effective approach to predict the occurrence of landslide under different precipitation conditions as well as landslide mechanics research. It can not only explain pre-existed landslides, but also predict the potential hazard region with environmental conditions changes. Finally, this paper carries out landslide hazard analysis and prediction in Yunnan Xiaojiang watershed, including landslide hazard sensitivity analysis and regression prediction model based on selected key factors, determining the relationship between landslide occurrence possibility and triggering factors. The result of landslide hazard analysis and prediction by coupled model is discussed in details. On the basis of model verification and validation, the modeling results are showing high accuracy and good applying potential in landslide research.

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Synthetic Geology Information System (SGIS) is an important constituent part of the theory of Engineering Geomechanics Mate-Synthetic (EGMS), and is the information system more suited for the collection, storage, management, analysis and processing to the information coming from engineering geology,' geological engineering and geotechnical engineering. Its contents involve various works and methods of the investigation, design, and construction in different stages of the geological engineering. Engineering geological and three-dimensional modeling and visualization is the fundamental part of the SGIS, and is a theory, method and technique by which, adopting the computer graphics and image processing techniques, the data derived from engineering geological survey and the calculated results obtained from the geomechanical numerical simulation and analysis are converted to the graphics and images displayed on the computer screen and can be processed interactively. In this paper, the significance and realizing approaches of the three-dimensional modeling and visualization for the complex geological mass in the engineering geology are discussed and the methods of taking advantage of the interpolation and fitting for the scattered and field-surveyed data to simulate the geological layers, such as the topography and earth surface, the groundwater table and the stratum boundary, are researched into. At the mean time, in mind the characteristics of the structure of the basic data for three-dimensional modeling, its visual management can be resolved into the engineering surveyed database management module, plot parameter management module and data output module and the requirement for basic data management can be fulfilled. In the paper, the establishment and development of the three-dimensional geological information system are probed tentatively, and an instance of three-dimensional visual Engineering Distribution Information System (EDIS), theConstruction Management Information System for an airport, in which the functions, such as the real-time browse among the three-dimensional virtual-reality landscapes of the airport construction from start to finish, the information query to the airport facility and the building in the housing district and the recording and playback of the animation sets for the browse and the takeoff and landing of the planes, is developed by applying the component-mode three-dimensional virtual-reality geological information system (GIS) software development kits (SDK), so the three-dimensional visual management platform is provided for the airport construction. Moreover, in the gaper, integrated with the three-dimensional topography visualization and its application in the Sichuan-Tibet Highways, the method of the digital elevation model (DEM) data collection from the topographic maps is described, and the three-dimensional visualization and the roaming about the terrain along the highway are achieved through computer language programming. Understanding to the important role played by the varied and unique topographical condition in the gestation and germination of the highly-dense, frequently-arising and severely-endangered geological hazards can be deepened.

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Population research is a front area concerned by domestic and overseas, especially its researches on its spatial visualization and its geo-visualization system design, which provides a sound base for understanding and analysis of the regional difference in population distribution and its spatial rules. With the development of GIS, the theory of geo-visualization more and more plays an important role in many research fields, especially in population information visualization, and has been made the big achievements recently. Nevertheless, the current research is less attention paid to the system design for statistical-geo visualization for population information. This paper tries to explore the design theories and methodologies for statistical-geo-visualization system for population information. The researches are mainly focused on the framework, the methodologies and techniques for the system design and construction. The purpose of the research is developed a platform for population atlas by the integration of the former owned copy software of the research group in statistical mapping system. As a modern tool, the system will provide a spatial visual environment for user to analyze the characteristics of population distribution and differentiate the interrelations of the population components. Firstly, the paper discusses the essentiality of geo-visualization for population information and brings forward the key issue in statistical-geo visualization system design based on the analysis of inland and international trends. Secondly, the geo-visualization system for population design, including its structure, functionality, module, user interface design, is studied based on the concepts of theory and technology of geo-visualization. The system design is proposed and further divided into three parts: support layer, technical layer, user layer. The support layer is a basic operation module and main part of the system. The technical layer is a core part of the system, supported by database and function modules. The database module mainly include the integrated population database (comprises spatial data, attribute data and geographical features information), the cartographic symbol library, the color library, the statistical analysis model. The function module of the system consists of thematic map maker component, statistical graph maker component, database management component and statistical analysis component. The user layer is an integrated platform, which provides the functions to design and implement a visual interface for user to query, analysis and management the statistic data and the electronic map. Based on the above, China's E-atlas for population was designed and developed by the integration of the national fifth census data with 1:400 million scaled spatial data. The atlas illustrates the actual development level of the population nowadays in China by about 200 thematic maps relating with 10 map categories(environment, population distribution, sex and age, immigration, nation, family and marriage, birth, education, employment, house). As a scientific reference tool, China's E-atlas for population has already received the high evaluation after published in early 2005. Finally, the paper makes the deep analysis of the sex ratio in China, to show how to use the functions of the system to analyze the specific population problem and how to make the data mining. The analysis results showed that: 1. The sex ratio has been increased in many regions after fourth census in 1990 except the cities in the east region, and the high sex ratio is highly located in hilly and low mountain areas where with the high illiteracy rate and the high poor rate; 2. The statistical-geo visualization system is a powerful tool to handle population information, which can be used to reflect the regional differences and the regional variations of population in China and indicate the interrelations of the population with other environment factors. Although the author tries to bring up a integrate design frame of the statistical-geo visualization system, there are still many problems needed to be resolved with the development of geo-visualization studies.

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Under the direction of Geo-informatic Tupu theory, based on comprehensive natural division in Xinjiang and 1:100000 land use and land cover vector data in 2000 from resource and environment database of CAS, the paper gave out some distribution Tupu of land resource types in different regions of Xinjiang. GIS tools such as ARCTOOLS and ARCV1EW were used to clip the unit of each natural division. Some useful conclusions were established. Then the lower reaches of Tarim River were selected as typical area to analyze the ecological environment evolvement from 2000 to 2004 since the beginning of ecological water delivering. The comprehensive space-time analysis provided a method to monitor the effect dynamically. The main contents of the thesis are listed as follows: (1) Similarities and differences between North Xinjiang and South Xinjiang, 6 second-classified regions and 37 third-classified regions. The conclusion of each region emphasized the percentage of area of main land types, characteristic description and distribution of cultivated land > woodlands grassland-, water area^ urban and rural land and unused land. (2) Thematic Tupu of each region. It concluded artificial oasis Tupu, the proportion between dense-grass% moderate-grass and sparse-grass, pattern of land resources and the land use degree. The artificial oasis mean cultivated land^ woodland^ urban & rural land and other construction land. The proportion of grassland disclosed the quality of all grassland and showed the development of them. Pattern of land resources and the land use degree gave out the detailed development direction and development degree of each region. (3) Ecological environment evolvement of the lower reaches of Tarim River. The effects of each ecological water delivering were compared.