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  • 2004 Volume 6 Issue 2
    Published: 25 June 2004
      
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  • ARTICLES
    On the Evolution of GIS and Its Meanings
    KONG Yunfeng
    2004, 6(2): 6-11.
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    The meanings of GIS and related topics are briefly reviewed and discussed in this paper. First,10 definitions of GIS from academic,industrial and governmental leaders since the late 1980s are briefly summarized. Second,several GIS-related topics,such as the National Spatial Data Infrastructure,GeoLibrary,GeoComputation,Geographic Information Science,OpenGIS Specifications and Digital Earth,and their academic background are introduced and analyzed. Third,considering the widespread of GIS technology and the emerging awareness on GIS and society,the author tries to investigate the close relationships among GIS,people,organization and society in the information era. Forth,GIS diffusion and several researches on GIS application in developing countries are emphasized. Besides geographic information technologies,it seems that there are quite a few economic,organizational and managerial challenges in GIS development in China and other developing countries.Based on the review of GIS concept and related issues,the author argues that: 1) The definition of GIS is diverse and the meanings of GIS have constantly evolved since the late 1980s. Nevertheless,spatial is special! The geospatial element is highlighted in all of the GIS definitions. On the other hand,the organizational and societal issues are becoming increasingly important in understanding GIS implementation,application,diffusion and utilization. 2) The field of geographic information is still new and immature in the context of information society. The contemporary technological and societal factors have begun to reshape GIS. Consequently,there exist quite a few scientific and empirical challenges in GIS research. 3) Along with the evolution of GIS,it is necessary to examine GIS from a broad socio-technical perspective. Researches on GIS and society,such as GIS and organization,GIS diffusion and utilization,are critical for GIS applications in developing countries. 4) The geographic information technology and knowledge are mainly developed in only some developed countries and embedded by their organizational and cultural traditions. Consequently,for GIS development in China,it is crucial to reexamine GIS meanings from social perspectives.
  • ARTICLES
    A TGIS-based Study and Realization on the Dynamic Visualization for Palaeoclimate Simulation
    LAI Geying, YU Ge
    2004, 6(2): 12-16.
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    Palaeoclimate is an important reference frame for the study of changes of modern and future climate. As palaeoclimate research is closely related to global change,it has become an important field of international geoscience. The key point in palaeoclimate research is how to reappear and rebuild palaeoclimate and to simulate the dynamic evolvement process of basic element fields of atmospheric circulation in the form of 3-dimensions (time as a dimension). In this paper,a model of temporal and spacial index (MTSI) is brought forward and an object of temporal and spacial index (OTSI) is created to deal with the corresponding relations of temporal progress and to solve the information query,display and analysis of palaeoclimatic basic factors(including temperature,precipitation,sea level pressure and 1000 hpa potential height) at t time on the dynamic visualization for palaeoclimate simulation. Using the object oriented programming platform,a TGIS-based dynamic visualization simulation of palaeo-climate (TDVSP) is completed and has a good visual effect. After a series of data files of palaeoclimate factors being opened,a video can be created in the TDVSP. In a video,there are two types of image formats(vector and grid) for demonstrating the dynamic change of the fields of palaeoclimatic factors,and the features of vector in image(e.g. isoline density,line width and line color) can be modified in runtime. In addtion,the two types of image formats at t time can be switched during running for researches to analyse the spacial pattern of the fields of palaeoclimatic factors. Moreover,every frame of a video can be saved as a picture.Therefore,TDVSP is a good tool for palaeoclimatic researchers to analyse,demonstrate and illuminate the results of palaeoclimatic dynamic simulation.
  • ARTICLES
    Fromework for the Integration of Resource and Environmental Modelbase
    FAN Zemeng, YUE Tianxiang
    2004, 6(2): 17-22.
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    Based on the developments of theories and techniques in the field of computer and system engineering on the modelbase system at home and abroad,after collecting,revising and categorizing the resources environment models we have had,we conducted the research progress of modelbase system theories and tried to design and explore the general platform of Resource and Environmental ModelBase System (REMBS) by taleing into the consideration of the integrated and complicated characteristics of these models. In order to take full advantage of those models and the avaiable knowledge and to create new models,the above-mentioned work should be done. The REMBS could offer the key techniques and support platform for solving the various and important issues of resources and environment. We designed the framework of the REMBS and the general scheme flows to realize the REMBS. Furthermore,we brought forward and designed the functions and structures of Resource and Environment ModelBase (REMB),resource and environmental model dictionary (REMD),Resource and Environment ModelBase Management System (REMBMS),and the framework to integrated REMBS and GIS,which are the key parts of REMBS. Finally,we discussed the benefits the REMBS could supply and the problems the REMBS could solve.
  • ARTICLES
    Development of Precision Rice Cultivation Information System Based on ComGIS
    WANG Juanle, CHEN Shenbin, LIAO Shunbao
    2004, 6(2): 27-30.
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    Component software development has become one of the main technique trends nowadays. Development technique based on COM-GIS has been widely used in GIS projects. Precision agriculture is the classic application for integrated GIS,GPS and RS,and this application needs support of farm GIS software. The paper studies the R&D of Precision Rice Cultivation Information System (PRC/INFO),which is used in China Precision Agriculture Experimental Unit in Shanghai.The paper analyses the key technologies and information procedure of precision rice cultivation initially. PRC/INFO can be decomposed by 5 parts in its general design based on its business logic. They are Attribute DB Management,Cropland GIS Management,Decision-making System of Rice Cultivation,Economic Evaluation System and System Integration. All the modules are organized in an integration system. Cropland GIS system provides the I/O interface and APIs for the whole platform. PRC/INFO is designed to be supported by ComGIS technology on the foundation of cropland GIS module. The platform is developed by Object-Oriented programming language. Its integrated development environment includes MS Visual Basic 6.0 components,SuperMapIII GIS components and lots of rice cultivation models. ComGIS development technology’s advantages are proved suitable to PRC/INFO in the development experience.
  • ARTICLES
    A Study on the Remote Sensing Inversion of Ocean Chlorophyll Concentration by Using Neural Network Method
    HUANG Haiqing, HE Xianqiang, WANG Difeng, PAN Delu
    2004, 6(2): 31-36,57.
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    One of the tasks of ocean color remote sensing is the measurement of marine primary production variation with time and space,whose important index is chlorophyll concentration of phytoplankton. The study on the inversion model of chlorophyll by remote sensing has been carried out for more than 30 years,and the main method is based on the ratio of blue and green channels. With the development of new ocean color remote sensors and new inversion methodology,the method based on fluorescence line high and neural network has being developed. In this paper,the neural network inversion is studied by means of the data set of global chlorophyll and in-situ radiance which was collected by SeaWiFS Bio-Optical Algorithm Mini-Workshop (SeaBAM). Finally,the result by neural network in the study is compared with that by Sea BAM’s empirical inversion.
  • ARTICLES
    Research on the Evaluating Models in SDSS for Location Selection
    HUANG Ling, LIU Zongwei
    2004, 6(2): 37-41.
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    Location selection is a very complex decision process which relates to many influencial factors. The evaluating models are used to express the relationship between the location and the influencial factors,and are the foci in the spatial decision support system for location selection. The traditional models include the Analytical Hierarchy Process (AHP),the Delphi Method and the regressive analysis model,etc. So,firstly,the author introduces these traditional models in brief: the principles,the processes and their characters. Some limitations of these modes are concluded,and then the author analyzes that the neural network (NN) model is useful and may cope with the troubles the traditional methods are faced,hence the NN model will be a perfect method to evaluate the location.Based on the characters of location selection,some difficulties in building the evaluating models are identified: (1) it’s very difficult to express the relationship among the complex factors; (2) according to the location selection problem for most establishments,there are limited criterions to describe the concerns and the rules affecting the factors; (3) it’s difficult to confirm the accurate formulae to express the real relationship be-tween the factors and the evaluating results; (4) some of the factors are very difficult to be expressed by accurate number; (5) some uncertainties hide in the analysis swatches. Then,the famous Error Back—Propagation network is introduced，and there are two very important points of it:optimizing the structure of the network and optimizing the learning algorithm of it.Genetic algorithm is a kind of stochastic search methods that mimic the metaphor of natural biological evolution.The author discusses the method to integrate the genetic algorithm (GA) and the neural network，and discusses how to use the genetic algorithm to optimize the structure and connected power of the network.Finally,integrating with a project of breach planning of a certain bank，this paper researches the process of evaluating the location by the neural network model，including the steps of implementing the method，and some concrete important outlines. It’s turned out that the evaluating model can play a steady role in evaluating the location. Based on analyzing the results in detail，some useful conclusions are also put forward in the paper.
  • ARTICLES
    WebGIS-based Study of Cicerone System for Chongqing
    JIANG Yongjun, LUO Bingliang, ZHANG Yuanzhu, KUANG Mingsheng, LI Hua, SHUAI Kaide
    2004, 6(2): 42-45.
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    When the human society enters the information era，information plays an even more important role in people’s life. Especially with rapid development of tourism,people need more and more information about tourism. Therefore,development of WebGIS-based cicerone system is a need of information era; also it has great effects on tourism necessity and the people’s travel. In this paper,the cicerone system of Chongqing was constructed,on the basis of comparison between the main platform and technological model of WebGIS,and in combination with the tourism development of Chongqing,as well as following the principle of being convenient to the user. The information of tourism resources was collected,stored,managed,analyzed,calculated and displayed in the form of pictures and graphs on the basic WebGIS platform by means of computer network and the database management. The travel information was comprehensively displayed in pictures and texts,sounds and images in the cicerone system. The cicerone system of Chongqing consists of three modules: basic database module,application analysis module and decision supported module. The former two modules are most important parts in the cicerone system. And the cicerone system of Chongqing can achieve three functions: to query the information of tourism,analyze spatial data of tourism information,and help making decisions. After the cicerone system is established,it will be published on the Web supported by WebGIS software. Supported by the basic database,by using WebGIS browser,the spatial query,the spatial analysis and assistant decision can be done on the Web by user. In this cicerone system,the reliable information and foundation were provided for the tourism management and tourism development of Chongqing city,and also for the people who want to take a trip to Chongqing.
  • ARTICLES
    A Structure Design for WebGIS-based Tourism Information System
    LIN Guangfa, CHEN Youfei
    2004, 6(2): 46-49.
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    Travel activity is a typical process in which the flows of the tourists,the material and the capital are induced by the flow of tourism information. The essence of the Tourism Information System (TIS) lies in the inducing and controlling of the other flows by tourism information flow. The Internet constructs a universal framework linking up the global information flow. To simulate the interactive mode between the above flows of the tourism industry,the best platform is Internet and Geographical Information System (GIS). The characters of the tourism information and their corresponding requirements to the system platform were listed (Tab.1). In the paper,the traditional TIS is divided into four subsystems as Hotel Information System,Travel Agency Information System,Destination Information System and Computer Reservation System,and each of the subsystem’s frame mode is summed up. The most critical defect of the present TIS is that its information flow is split. TIS must be focused on the management of information flow and its structure should be designed to ensure extensive and steady flow of the tourism information. To provide decision support to the user,the interactive mechanism between the factors in the tourism flow system must be worked out and the specific spatial analysis function and multimedia geographical information expressing function of WEBGIS should be recurred to. Combining the above analysis with the present status of our country’s tourism industry in the background of globalization,the paper developed an integrated framework of TIS based on WEBGIS (Fig.2).
  • ARTICLES
    Interpolation Methods in Geological Simulation
    WU Chunfa, LI Xing
    2004, 6(2): 50-52.
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    Geological simulation is one of the most important methods in geological study. The geological problems belong to macroscopical and continuous problems. But,we could only get finite and discrete data of spatial swatch. We need to convert them to continuous and visual geological section plane or geological body by using some interpolation methods. We should use the geological data sufficiently to get more useful information for geological study,because it is very difficult to collect geological data and the collection expense is very high; so data interpolation is one of the more important issues in geological simulation and also one of the important technical methods in geological data processing. It is not only the core of geological simulation,but is also is the guideline for the interpolation method selection,namely，“Preventing distortion of simulation,improving the precision of simulation”. The selection of interpolation method in different geological simulations is determined by the complexity and levity of geological body and the special applicable range of existing interpolation methods. The method of interpolation which we chose affects the precision and reality of simulation directly. In this paper,we briefly introduce the principle and applicability of several major and widely used geological data interpolation methods in allusion to the complexity of geological data interpolation in geological simulation,and discuss the choice of geological data interpolation method in different conditions.
  • ARTICLES
    Study of Urban Land Optimal Allocation: A Case Study of Jinan
    ZHAO Tao, ZHENG Xinqi, DENG Xiangzheng
    2004, 6(2): 53-57.
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    Urban land is the base for urban social and economic development. The variation of urban land-use structure brings different economic,social and environmental benefits to urban areas. At present,the land-use structures of most of the cities in China are,more or less,irrational. This has restricted the development of urban areas and the process of urbanization. For improving the level of intensive land-use,optimizing the structure of urban land and realizing the sustainable development of urban areas,this paper carried out a tentative study on urban land optimal allocation. Supported by RS and GIS,the suitability evaluation of urban land was implemented. And then,the optimization of quantitative structure of Jinan’s urban land was completed using a system-dynamics model established by us. Finally,the spatial allocation of Jinan’s urban land was performed automatically by a module developed using AML. According to the simulation results,the land use structure and the distribution of each kind of urban land use type will be optimized evidently,which is mainly characterized by the decrease of the land used to industrial production and its distribution shifted to the urban periphery. This paper integrated the AHP,systematic dynamics and land suitability evaluation with the optimal allocation of urban land use,which formed a framework for relative studies and have positive meaning to research of the pattern of land optimal allocation at the regional scale.
  • ARTICLES
    System for Scientific Literature’s Spatial Expression and Web Searches Based on ArcIMS
    LUO Yongfeng, YANG Xiaomei, ZHANG Hongyan
    2004, 6(2): 58-62.
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    At present,research on WebGIS’s application has become a new topic in GIS fields. This article analyses the architecture,the specialty,and the information’s transmit mechanisms of the ArcIMS 4.0，which is a new generation map service platform; using ASP technique,the literature database system about China′s coastal zone which can be queried on net was established by combining the platform of ArcIMS 4.0 with the technology of JSP for the realization of relation query between literature’s data and spatial data about China′ main sea sectors; and the successful implementation of the project provided scientific basis for both research on and application to WebGIS fields,meanwhile a new way for publishing spatial data and attribute data was provided.
  • ARTICLES
    Study on Extraction Method of Land Use Information
    DANG Anrong, HE Xindong, SHI Huizhen, GUI Dan
    2004, 6(2): 63-66.
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    S technologies,which refer to Remote Sensing (RS),Geographic Information System (GIS),and Global Positioning System (GPS),are very important techniques in resources investigation and environmental protection because of the unique characteristics in information acquiring,processing,and analyzing. For extraction of land use information,four main methods have been used until now,such as traditional manual interpreting method，humancomputer interactive interpreting method，computer aided auto-classification method,and multi-information complex interpreting method. After analyzing the advantages and disadvantages of each of the above method,a new kind of method called integrated auto-classification method is put forward based on mature auto-classification methods. Taking Miyun County,Beijing as a case region,the land use information was extracted by means of the new method-integrated auto-classification method supported by 3S technologies. A series of contrast analysis have been done between the new method and traditional method. Result of this study can be deduced that the new method has some advantages in objectivity,scientificness,and practicability.
  • ARTICLES
    Construction of the Red-tide Remote Sensing Information Systems and Its Application
    LENG Xiuhua, ZHANG Jie, ZHAO Wei, LI Ruixiang, SONG Pingjian
    2004, 6(2): 67-71.
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    Based on remote sensing information of red tide organisms and the related data collected simultaneously,such as the spectrums,the observation data of biology,chemistry,hydrography and meteorology,the database algorithmic functions for the data processing of ground object spectra and that for the extraction of the predominant species of red-tide organisms as well as related biological information from ground object spectra are developed in the environment of the integrated Visual FoxPro System. Furthermore,an application system is constructed for the detection of the boom of red-tide organisms,the recognition and identification of the predominant species of red-tide organism,and the analysis of their characteristic values. The flow chart of management and the main functions of the system are described,the design of the system construction and the realization of each module of the system are depicted,and analysis of some application cases of the system is provided. The system under consideration can provide effective tool for marine environmental protection and for the researches on the reduction of red-tide disasters,and can also provide quantified object data for the govermment departments (in charge) of natural resources and environmental administration.
  • ARTICLES
    Virtual Reality Technology Application in the Digital South-to-North Water Transfer Project
    HE Ling, HU Wenliang, SUN Hailong
    2004, 6(2): 72-76.
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    This article looks back the development of virtual reality technology and introduces the south-to-north water transfer project briefly. The south-to-north water transfer project contains three main routes—the eastern，the middle and the western routes.The middle route passes the province of Hebei.Taking the middle route for example，this article deals with the environment of engineering implementation and the design of virtual reality technology of the project in detail. Then virtual 3D moddle is built. On the basis of it,the article analyzes the result of this design，such as display of 3D scene,optimum route selection,buffer analysis and calculation of earthwork,grade and length. This article ends with a conclusion.
  • ARTICLES
    Research and Discussion on Geographic Information Classification and Coding of House Property
    TIAN Ran, LV Guonian, ZHANG Hong, FENG Wenzhao
    2004, 6(2): 77-80,87.
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    The coding scheme for classifying House Property thematic geographic information is the bedrock of House Property information management and information application,and that really determines whether or not you succeed in information system construction. If the established coding scheme is illogical，it will increase workload in building a geo-database and do great harm to the use of database or data sharing. It even can shorten the database lifecycle and we will suffer huge loss. Thereby,perfect coding scheme for classifying House Property thematic geographic information is very crucial to achieving system and data management and data application goals. With the help of the experience in requirement analysis and data integration,parts of “Digital House Property” sharing platform of Nanjing Project,and in consideration of the need of information sharing across departments and cities,the writers put forward a coding scheme for classifying House Property thematic geographic information. We expected that is a rewarding work on geographic information standardization of House Property.
  • ARTICLES
    The Analysis of the Spectrum-reflecting Characteristics of the Typical Objects along the Beach in Subei Using Hyperion Data
    TANG Bohui, JIANG Xiaoguang, TANG Lingli, XI Xiaohuan, DAI Changda
    2004, 6(2): 81-87.
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    Hyperspectral remote sensing technology is one of the most important leading fields in remote sensing which is paid more and more attention in the world. The successful launch of Hyperion in November 2000 provided a new and useful tool for remote sensing applications. Hyperion imaging spectrometer has the highest spectral resolution in orbiting satellites,and shows great application potential. Taking Subei district,Jiangsu province as a study area,this article analyzed the characteristic of EO-1 Hyperion data,studied the general method and procedure of calculating the spectral value of image from its grey value,selected 15 kinds of typical object samples and deduced their spectral curves in wavelength ranging from 400 nm to 2 500 nm. The feature of objects can be seen clearly from deduced spectral curves. Since the imaging time of the data was in late winter (10:19 am,January 15,2003),the vegetation withered and no typical spectrum characteristics of vegetation were displayed in visible wavelength. But in near-infrared region there was still a high reflecting peak. In short wave infrared wavelength,the reflection value is lower than that of near infrared because of the influence of water absorption. At the high tide time,the difference between river water and seawater was evident. The reflectance of seawater was much higher than that of river water because the seawater contained more mud and sand. The reflection value of turbid water is lower than that of clean river water in green wavelength and higher in red and infrared wavelength. Probably this is caused by the higher content of organic material and algous vegetation in turbid water. In salt field,the spectral reflection values of depositing pool,evaporation pool and crystal pool rose in turn with the increase of salt amount.
  • ARTICLES
    Optimum Technique of Remote Image Lossy Compression Based on Wavelete Transform
    ZENG Yong, FU Qiaoyan, WANG Wenyu, HE Shanming
    2004, 6(2): 88-91.
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    In the domain of surveying and mapping,users present rigorous requirement for the image quality. But there are noises in the image data,hence it is possible to perform lossy compression. In this paper,an optimum technique about remote image lossy compression based on wavelete transform is presented. First,we analyse the disadvantage of data compression based on discrete cosine transform; then we adopt the method of two-layer and two-dimension wavelete transform to decompose original image; finally,according to the characteristics of remote sensing images,optimal quantizers are constructed based on LMSE principle to meet the high quantity compression. At the same time,according to the experiment,the rough relation between the compression rate and p-p SNR is acquired.
  • ARTICLES
    An Application of Wavelet Package Analysis to the Signal Compression
    YANG Chao, XU Zeyin, LU Yurong
    2004, 6(2): 92-96.
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    Wavelet package analysis has been rapidly developed based on wavelet transform in recent years. Signal was expressed as a linear combination of a set of best bases of wavelet package,the energy of expansion coefficients are concentrated in a small number of coefficient because of the good location properties of wavelet package best bases. So it is possible to achieve high compression ratios without any loss of useful and important information of the compressed signal. Owing to the limitation of wavelet transform,the authors of this paper have researched wavelet package analysis in the signal compression and given some experimental verifications.
  • ARTICLES
    Eco-environmental Dynamics of Jinjiang City
    ZHUANG Jianshun, CHEN Songlin, CHEN Wenhui
    2004, 6(2): 97-100.
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    Based on multi-temporal remote sensing images of Jinjiang city in Fujian province acquired in 1988 and 2001,together with auxiliary data and geo-knowledge，we establish the formation characteristics and the classification system of the eco-environment in Jinjiang city. By interpreting the Thematic Map of ecoenviron-ment in this area and analyzing the current situation of Jinjiang city’s land use,we then get two ecoenvironmental maps in two different periods. Combined with the analysis of the quantity of eco-environment,characteristics of their distribution and the rule of their dynamic changes,we establish the spatial and temporal analysis model for measuring the rate of ecoenvironmental changes. In conclusion,the paper points out that the changes of two eco-environments in this area are vigorous,and the settlements of urban and rural eco-environment have increased greatly,while the area of eco-environment in platform dryland decreases drastically. And the obviously changing city space could be divided into three areas: the northeast developing area,the southwest developing area and the central newly developed area. In the northeast and southwest developing areas,their development trends radiate along the transportation lines. But the central newly developed area has changed as the hub shapes outwardly.
  • ARTICLES
    Identification of Seismic Belts from Earthquake Points by Skeleton Operation of Mathematical Morphology
    QIN Chengzhi, PEI Tao, ZHOU Chenghu , LI Quanlin, WANG Min
    2004, 6(2): 101-105,114.
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    This paper aims to extract the spatial distribution of discrete point events by means of image processing after conversion from the discrete field to the image field.For identifying the seismic belts,this paper creates the gray-value density image from the discrete earth-quake points by means of “sliding windows” and uses the Skeleton operation of mathematical morphology to extract out the skeleton where denotes the position of seismic belts. The identifying prodcedure analyzes the connectivity of the gray-value density image of earthquake distribution firstly. The main connective components are thought as the correspoonding position of seismic belts where the earthquakes are dense. After used the Fourier filter to smooth the main connective component image having noise,the Skeleton operation of mathematical morphology is used to extract out the skeletons as the position of identified seismic belts. After the artificial data is used to test the validity of this method,this method is applied to the earthquake records of the Great North China. The results are statistically verified by the Buffer analysis of GIS. The seismic belts drawn by seismologist are also compared. The result is satisfactory.
  • ARTICLES
    Extracting the Information of Concrete/Urban Development from High Spectrum Resolution Image of ASTER
    WANG Chunlan, CHEN Jianfei
    2004, 6(2): 106-108,124.
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    This paper introduced ASTER image as the sign of a high spectrum resolution era. A comparison was made between high spectrum resolution images and previous common remote sensing images. Great differences between ASTER and other common images such as TM are obvious as far as some technical parameters are concerned. It is clear that high spectrum resolution images could be information resources of higher quality. ASTER images are very useful in various fields,such as glaciology,hydrology,urban expansion,volcanic forecast,evapotranspiration / surface temperation and geology. In this study,an ASTER image,covering the citywide of Fuzhou，is preliminarily disposed during some pre-classification processes such as principal com-ponents analysis and band math. In principal components analysis process,the entire information of the initial images was compressed to six bands of the disposed image，which can well represent initial information and meanwhile can make concrete/urban buildings more distinct.In the process of band math,which is based on the spectrum characteristics of previous image,a common band math formula,B1-B2,is used. B1 and B2 represent Band 1 and Band 2 in the previous image respectively. The value of B1-B2 depends on the type of land cover. Two kinds of values can be seen,the one greater than zero represents buildings and the one smaller than zero represents natural cover such as trees or water bodies. Unsupervised classification method of Isodata is used to extract the cover of buildings. Then the disposed image is used to extract the concrete/urban development information of the research area with a good result. This result can be used in further analyses,such as urban planning,urban environment evaluation with ecological theory of interstice and so on.
  • ARTICLES
    Preliminary Approach to the Informatic TuPu of the Complex Ecosystem
    SHI Jianping
    2004, 6(2): 109-114.
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    The informatic TuPu of the complex ecosystem is the GIS based development result. It is an assistant means to elaborate the study on the complex ecosystem,and has a premising future in application. It is helpful to study directly on the temporal and spatial features of the complex ecosystem with the informatic TuPu. This can play an assistant function for reseaching the features,future,laws,and decision support.In this paper,the autor expounds the necessity of establishing the informatic TuPu of the complex ecosystem,and promotes the basic framework and design philosophy to the structure of the informatic TuPu of the complex ecosystem. Furthermore，questions have aroused our attention in the development and application. These questions are how to distinguish the difference between the informatic TuPu of the complex ecosytem and information database and electron atlas,how to carry through assistant reseach by th informatic TuPu so as to get more in-depth conclusion than general reseach. Meanwhile,three parts reflecting the current state,revealing the feafures,and virtualing the future are put forward to the application of the informatic TuPu of the complex ecosystem by taking Fujian province as an example.
  • ARTICLES
    Analysis of Oasis Neighborhood Patterns and Ecological Model in Xinjiang
    LI Jianxin
    2004, 6(2): 115-119.
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    The oases are located along the foot of the mountains in linear,fan-shaped and radial patterns and linked to each other from north to south in Xinjiang through road systems. The distributions of these oases are in bow-shaped pattern with an arrow pointing to the west. The oasis economy is mainly based on water,soil and minerals resources. The number of neighbors and the distance between neighbors are not the key conditions to determine a central city in the region. The central cities at the county level have a population of less than 100 000,with the mean number of 3.50 neighbors,and at an average distance of 144 km from other neighbors. The central cities at the prefecture level have a population ranging between 100 000 and 600 000,with the mean number of 4.25 neighbors and at an average distance of 450 km from other neighbors. The oasis population is growing constantly and has a population density reaching 233/km2. The policy of ecological conservation will turn the oasis economy into an island model,because the restrictions on conservation areas will keep the oasis region to be used as farmlands within some defined bounds. The industrialization and urbanization in the oases will be the next mode of development for small and medium-sized cities in the region. The large cities,with a population of more than one million living in a 2 000 km radius around Urumqi,the capital city of Xinjiang,are not economically better developed than Urumqi,therefore,they are not able to support the rapidly developing economy in Urumqi. The pattern of the neighborhood around Urumqi that influences Urumqi’s economy is not the pattern of the neighborhood at the same level,but the pattern of the neighborhood at the higher level. Urumqi is located in the middle of the railway (New Silk Road) linking Asia and Europe,making Urumqi a significant economic and travel hub. The Shanghai region at a distance of 4 000 km and the West Europe at a distance of 6 000 km from Urumqi should be considered as the supporting neighborhood for economy in Xinjiang.
  • ARTICLES
    Research on Omen Information Tupu of Ecological Landscape Based on RS
    LIN Zhilei, SHA Jinming
    2004, 6(2): 120-124.
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    Since being raised the concept of Digital Earth has been discussed by scientists all over the world. With the introduction of Digital City,Digital Fujian,Digital Fuzhou and Digital Xiamen are being arranged. As the technological system has strong point,it is quite promising to apply nationwide. Geometric Tupu is a basic technique for chart expression of space-time in Geometry. The thesis involves a tentative research into Omen Information Tupu of Ecological Landscape on the basis of RS technology,and Fujian’s Yongtai County is taken as an object of study. Remote sensing is employed to monitor various elements of the ecological environment,including water,energy and basic ecological units. Meanwhile water and heat conditions and forest types are analyzed. Thus the study of the omen information of ecological landscape is on the basis of RS technology. It is possible to keep data up to date via monitoring by RS. Ecological landscapes are classified into different types to establish a classification system and to draw up a landscape diagram,followed by the analysis on the structure and the change of the ecological landscape.