CREATION OF THE SYSTEM OF DISTRIBUTED SHAREABLE GEOGRAPHICAL DATA BASES FOR CARRYING OUT COMPLEX RESEARCHES OF TERRITORIES

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1 CREATION OF THE SYSTEM OF DISTRIBUTED SHAREABLE GEOGRAPHICAL DATA BASES FOR CARRYING OUT COMPLEX RESEARCHES OF TERRITORIES Irina K. Lourie, Aly R. Alyautdinov, Dmitryi V. Michayilov Department of Cartography and Geoinformatics, Faculty of Geography, Moscow State University, Leninskiy Gory, , Moscow, Russia Abstract. The article represents one of ways of creating system of geographic shared database (DB) supporting vector and raster formats of main geosystem components, and non-formatted data as well. At conceptual level of designing database systems (DBS) one elaborates the classification of models of spatial objects and data for representation, organizing and complex geographical analysis of information. The DBS includes thematic database of GIS and some autonomous attributive DBMS, containing data on geographical descriptions of studied objects. Under DB creation the main attention is attributed to the development of effective data model and handy user interface for work with records; to the maintenance of descriptions georeferencing under field studies in DBMS Access environment. The elaborated interface allows on basis metadata to manage a versions DB and to control user s actions, for example checking correctness of entered values. INTRODUCTION The fundamental problem of geoinformatics - integration of data in GIS and forming infrastructure of the spatial data, demands for performance of theoretical and technological developments of ways of their accumulation, thematic coordination and data exchange. The concept of model in geoinformatics concerns both to real objects of geosystems, and their representations in DB of GIS-package. In GIS the choice of the data model is crucial at the stage of DB creation. The choice of formal model of spatial objects defines the physical structure of DB and the program model of DBMS in computer realization (1, 2, 4). The current tendency for creation and management of geographical DB is focused on the use of object-oriented technology. However, while such DBMS have lower productivity than relational DBMS (RDBMS), they are expensive and poorly accessible. Therefore relational DBMS still remain popular, and the perfectioning of commercial DBMS for spatial data management remains rather urgent issue. Among the ways of RDBMS perfectioning there is an elaboration of combined objective - relational DBMS. For the increase of functional efficiency of these DBMS it is possible to create classes of objects with corresponding tables. Thus each object combines from records in several tables i:e. table of basic class and corresponding tables. Research problems and the initial information The submitted research includes the following developments: definition of theoretical and technological ways of integration of different types spatial data in shared DB; development of ways of data quality estimation and requirements to metadata; development of structure of system of distributed databases; creation of the general(common) thematic database and of some local attributive databases for everyone components of geosystem; creation of databases server and organization of access to a local network, including spatial inquiries to databases objects. Improvement of techniques of these problems decision is of s carried out by creation of working system of the distributed shared databases which should ensure the functioning with spatial information, placed in local DB of departments of geographical faculty of the Moscow State University, with access to each of them through a local network and a server of databases on faculty of cartography and geoinformatics.

2 The sources of the information on a complex characteristics is the key-site territory within the limits of Smolensko- Moskovsskaja high plain (the area about 30 sq.km). where is situated the oldest field scientific station Satino (belonged to Geographical faculty, Moscow State University). Since 1968 complex scientific researches have been carried out here by many researchers and students of geographical faculty. The main sources of information for DB filling are: digital topographic maps scales 1:5 000 and 1:10 000; series of paper maps of the territory made on the basis of paper topographic map scale 1:10 000; series of photopalns and air images for different years massif of geodetic network coordinates for the territory (a layer of reference points); materials of the long-term field inspections accompanied with analytical processing or descriptions, annually updated during field study period; digital materials in raster format created by faculty s educational GIS (the first version. 1995). Methods At a conceptual level of designing of system BD classification of models of the spatial information is determined. It connects properties of real objects and data on them can be presented as the following hierarchical structure (3): - Conceptual models of reality representation; - Models of data on spatial objects; - Models of DB objects; - Models of DBMS; - Models of geospace. Ways of an estimation of quality of the data are especially investigated. It is known, that standard DBMS doesn t correspond to spatial character of information at the level of database designing we determine two types of DBMS supporting different models of data (5). For keeping autonomous attributive DBMS, which support studies of different departments, DBMS MS Access was chosen to give the opportunity of creation and functioning rather small DB in client server system. Decisions on the base of MS Access are simple in operation, and system administration doesn t demand for the constant presence of an expert in database area. Besides that, format of MS Access DB s is supported by GIS-package MAPINFO creating blocks of thematic spatial data in shareable databases. Georelational model of DBMS of GIS-package MAPINFO was chosen for thematic spatial databases both local and shareable. This model enables handy storage of multipleparameter geographical information and ensures working with digital maps. The model of thematic DB is based on the layer-by-layer description of spatial objects determined in scheduled coordinates in common for all layers system. Layers of DB are organized in the thematic blocks created under uniform requirements on different faculties of geographical faculty of the Moscow State University (fig. 1). Technique of creation independent attributive DB The storage of all complex attributive information on the territory in DB commonl for all GIS users complicates both its editing, updating, and its use in studies on separate landscape components. That s why it is decided to create the system of autonomous attributive DB, providing storage and analysis of materials of long-term field inspections of territory studied by the experts in different branches of geography. Filling of each of local DB is carried out by experts in the area of a geographical science: geomorphology, geochemistry ïî â, biogeography, cartography and geoinformatics. Creation of systems BD it is carried out by development as ways of the organization and estimation of quality of the integrated data, formation of structure metadata, and technologies of access to objects DB of clients of the local computer network with observance of autonomy of these DB. On a server of databases the software of processing of the geographical data, including geoimages (digital maps), pictures, models), and also means visualization of the information of all DB is placed. Relationships of general thematic and local attributive DBs are submitted on fig. 2. Under the process of DB construction the main attention was given to the developmant of effective data model and elaboration of handy user interface for viewing, editing, adding or deleting records. Simultaneously elaborated functions of the interface can control user s actions, for example, check correctness of entered values. As that DB is oriented for researchers and students who can exploit it during field studies at the scientific station, the program interface is rather

3 simple in use and thus has all necessary tools for working with data. DB contains descriptions and coordinates of various geographic objects georeferenced to basic thematic layers of GIS DB. BASIC LAYERS Topographical basis: relief (isolines) ground control points (pyramids, refer. points) contours of a forests; rivers, lakes, bogs Photoplan of THEMATIC BLOCKS: Geomorphology Microclimate Hydrology Soils Biotic Landscapes Landuse DERIVATIVE LAYERS: DEM Slopes Exposition AIR-SPACE IMAGES AUTONOMUS DB: "Geology parameters" "Soil-geochemical " "Geobotanical " Figure 1. Structure of database GIS The program interface for working with autonomous attributive DB is created as Windows applications. For the access to separate objects of DB and allowable for the given user operations in DB area are used main menu and tool panels. For the maintenance of information analysis in MS Access user s designer of inquiries is specially elaborated. Except for basic tables in DB it is created more than 40 additional references, so called qualifiers, the part of them contain modern scientific classifications of natural objects. For representation of ultimate results automatically created forms and reports are developed. Figure 2. Structure of relationships thematic and external DBs The main table in any autonomous DB is the table of basic studied object containing its characteristics and links with components of this object (see Figure). The unique identifier of object in a form of compound index is used as initial key. Other tables connected with the main one store descriptions of different studied objects within the limits of some area around the point of supervision and include qualifiers of parameters (see Fig. 3). Connections between different tables of DB are carried out by means of the unique identifier of basic object, the

4 identifier of each component and the identifier of each class (see Fig. 4). Figure 3. Structure of relationships in external DBs The table of basic class is linked with corresponding tables by means of initial key ID (in relation one to one). This IDs has integer value promoting simplification of links analysis. Objects of different classes as well as in usual RDBMS correspond to separate records in tables. The ID of base object in a table is the identifier of an object. Thus each object combines from records in several tables i:e. table of basic class and corresponding tables. Tables of classifications Figure 4. Relationships of objects in external DBs For the all natural phenomena descripted in DB the majority of parameters are qualitative. For the maintenance of work with qualitative or ranged parameters we create special tables - tables of classifications. They are analogue of qualifiers, i.e. represent grouped lists of values of qualitative or ranged parameters with final number of classes depending on required detailization of the given parameter. Due to such approach basic tables containing objects descriptions store only identifiers of classes. All tables of classifications are connected to tables of object descriptions in relation "one to many". In practice it is impossible to imply such approach, using only standard means of MS Access. That s why for successful DB functioning it s necessary to elaborate the special interface which allows to take all the advantage of using tables of classifications.

5 The distinctive feature of DB s is the maintenance of georeferencing of the all field studies points. The special module allows to specify coordinates of any object both in the window of the map created in MS Access environment (user can define himself structure of layers necessary for referencing), and by means of direct input of known coordinates received from GPS. Due to presence of spatial data it is possible to use information of autonomous attributive DB in thematic shareable DB and as a result, to carry out complex analysis of given field research and GIS layers. APPLIED RESULTS As a result of the executed development materials of research of territory are systematized and created: the program interface and an autonomus database more than 2000 soil - geochemical descriptions; a set of description with records of parameters of a geological and geomorphological structure of a key territory; structure geobotanical DB. Practical work with GIS is divided into two stages: field studies: data gathering with the use of conventional field geographical research methods and representation of obtained data focused on the digital form of their storage in DB (for that purpose specialized program interface in MS Access is developed); generalization of data and methods at a modern scientific and technical level of research in laboratory both during field studies period and as a result of research and mapping during preparing degree papers. THE CONCLUSION Development of theoretical positions of spatial data integration in shareable DB, data quality estimation and requirements to metadata it is executed with the use of modern geoinformatic technologies and introduce an original approach. Experts in different branches of geography for the first time havw got access to thematic information reflecting features of hierarchical structure and functioning of research territory that will allow them to solve theoretic and applied multidisciplinary tasks of geography. ACKNOWLEDMENT This research, described in this paper was supported by the Russian fund of fundamental investigations (project ), scientific school project ( ) and program "The University of Russia" ( ). REFERENCES 1. Burrough P. A. and McDonnell R. A. Principles of Geographical Information Systems. Oxford University Press pp. 2. Core Curriculum in GIS. Edited by Michael F.Goodchild and Karen K.Kemp Published by: National Center for Geographical Information and Analysis (NCGIA) University of California, Santa Barbara, USA, 1991, Vol Lourie I.K., Principles of Geoinformatics and Building a GIS. MSU. 143 pp. 4. Plewe B. GIS Online: Information Retrieval, Mapping, and the Internet. Geoinformation International, Cambridge, UK, 1997, 311 pp. 5. Zeiler M. Modeling our World. The ESRI Guide to Geodatabase Design. ESRI Inc p. 199

6 Biography of authors of paper "Creation of the system of distributed shareable geographical data bases for carrying out complex researches of territories" Name: Lourie First name: Irina Date of birth: 05 Dec 1942 Citizenship: Russian Federation Sex: female EDUCATION M.S. in Mathematics, Faculty of Mathematics, Moscow State University, Moscow, Russia scientific researcher Faculty of Geography, Dep t of Cartography and Geoinformatics, Moscow State University present Professor Dep t of Cartography and Geoinformatics, Moscow State University DISSERTATIONS: --Phd in Geographical science, 1989 ; --Doctor of Geographical science, 1998 "Theory and practice of creation of educational GIS" LECTURER "Principles of geoinformation mapping", "Geoinformatics", "Principles of geoinformatics and building a GIS", "Theory and practice of digital image processing" PRINCIPAL RESEARCH INTERESTS Geoinformatics and GIS-technology, Geoinformation mapping, Automated image processing for thematical mapping, development of special Data bases and educational GIS ADDITIONAL INFORMATION --Author of more than 140 scientific publications -- Have certificate of ESRI and Erdas Companies as specialist in program products ArcInfo, ArcView3, Erdas Imagine Name: Aliaoutdinov First name: Ali Date of birth: 18 Jan 69 Citizenship: Russian Federation Sex: male alik@geogr.msu.ru EDUCATION M.S. Faculty of Geography, Moscow State University, Moscow, Russia postgraduate student, Dep t of Cartography and Geoinformatics, Moscow State Uni present - scientific researcher Dep t of Cartography and Geoinformatics, Moscow State University PRINCIPAL RESEARCH INTERESTS surface modeling, geostatistics, geometric modeling, digital cartography, development of GIS systems, map projections, information technoloigies, networking ADDITIONAL INFORMATION -- Author of more than 20 scientific publications -- Have certificate of ESRI and Erdas Companies as specialist in program products ArcInfo, ArcView3, Erdas Imagine Name: Michayilov First name: Dmitryi Citizenship: Russian Federation Sex: male EDUCATION M.S. Faculty of Geography, Moscow State University, Moscow, Russia.

7 present - postgraduate student, Dep t of Cartography and Geoinformatics, Moscow State University