{"id":1614,"date":"2015-01-19T05:55:50","date_gmt":"2015-01-19T01:25:50","guid":{"rendered":"http:\/\/israaa.ir\/?p=1614"},"modified":"2020-02-03T02:43:03","modified_gmt":"2020-02-02T23:13:03","slug":"%d8%a7%d8%b5%d9%88%d9%84-%d8%b3%db%8c%d8%b3%d8%aa%d9%85-%d8%a7%d8%b7%d9%84%d8%a7%d8%b9%d8%a7%d8%aa-%d8%ac%d8%ba%d8%b1%d8%a7%d9%81%db%8c%d8%a7%db%8c%db%8c","status":"publish","type":"post","link":"http:\/\/israaa.ir\/?p=1614","title":{"rendered":"\u0627\u0635\u0648\u0644 \u0633\u06cc\u0633\u062a\u0645 \u0627\u0637\u0644\u0627\u0639\u0627\u062a \u062c\u063a\u0631\u0627\u0641\u06cc\u0627\u06cc\u06cc"},"content":{"rendered":"

\u0645\u062e\u0627\u0637\u0628 \u06af\u0631\u0627\u0645\u06cc :<\/span><\/strong><\/span><\/p>\n

\u0645\u062a\u0646 \u062d\u0627\u0636\u0631 \u0646\u0648\u0634\u062a\u0627\u0631\u06cc \u0627\u0633\u062a \u06a9\u0647 \u0627\u0635\u0648\u0644 \u0648 \u0633\u0627\u062e\u062a\u0627\u0631 \u0633\u06cc\u0633\u062a\u0645 \u0627\u0637\u0644\u0627\u0639\u0627\u062a \u062c\u063a\u0631\u0627\u0641\u06cc\u0627\u06cc\u06cc \u0631\u0627 \u062f\u0631 \u0642\u0627\u0644\u0628 \u062a\u062d\u0644\u06cc\u0644 \u0645\u0628\u0627\u0646\u06cc \u0628\u062e\u0648\u0628\u06cc \u062a\u0634\u0631\u06cc\u062d \u0645\u06cc \u0646\u0645\u0627\u06cc\u062f. \u0627\u0632 \u0627\u06cc\u0646\u0631\u0648 \u0628\u0627 \u0627\u0645\u06cc\u062f \u0628\u0631\u0627\u06cc \u0642\u0627\u0628\u0644 \u0627\u0633\u062a\u0641\u0627\u062f\u0647 \u0628\u0648\u062f\u0646 \u0639\u0644\u0627\u0642\u0645\u0646\u062f\u0627\u0646 \u0645\u0628\u062d\u062b \u0633\u0646\u062c\u0634 \u0627\u0632 \u062f\u0648\u0631\u060c \u062c\u0647\u062a \u0645\u0637\u0627\u0644\u0639\u0647 \u0648 \u0627\u0633\u062a\u0641\u0627\u062f\u0647 \u0645\u062d\u0642\u0642\u06cc\u0646 \u0627\u0631\u0627\u0626\u0647 \u0645\u06cc \u06af\u0631\u062f\u062f.<\/span><\/strong><\/span><\/p>\n

\u00a0<\/span><\/p>\n

    \n
  1. Introduction\u00a0<\/strong><\/span><\/li>\n<\/ol>\n

    We are presently positioned at the beginning of twenty first century with the fast growing trends in computer technology information systems and virtual world to obtain data about the physical and cultural worlds, and to use these data to do research or to solve practical problems. The current digital and analog electronic devices facilitate the inventory of resources and the rapid execution of arithmetic or logical operations. These Information Systems are undergoing much improvement and they are able to create, manipulate, store and use spatial data much faster and at rapid rate as compared to conventional methods.<\/span><\/p>\n

    \u00a0<\/span><\/p>\n

    \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 An Information System, a collection of data and tools for working with those data, contains data in analog form or digital form about the phenomena in the real world. Our Perception of the world through selection, generalization and synthesis give us information and the representation of this information that is, the data constitute a model of those phenomena. So the collection of data, the database is a physical repository of varied views of the real world representing our knowledge at one point in time. Information is derived from the individual data elements in a database, the information directly apparent i.e. information is produced from data by our thought processes, institution or what ever based on our knowledge. Therefore in a database context the terms data, information and knowledge are differentiated. It can be summarized that the data is very important and added value as we progress from data to information, to knowledge. The data, which has many origins and forms, may be any of the following:<\/span><\/p>\n

    \u00a0<\/span><\/p>\n

      \n
    1. Real, for example the terrain conditions etc.<\/span><\/li>\n
    2. Captured, i.e. recorded digital data from remote sensing satellites or aerial photographs of any area.<\/span><\/li>\n
    3. Interpreted, i.e. land use from remote sensing data.<\/span><\/li>\n
    4. Encoded i.e. recordings of rain-gauge data, depth of well data etc.<\/span><\/li>\n
    5. Structured or organized such as tables about conditions of particular watershed.<\/span><\/li>\n<\/ol>\n

      \u00a0<\/span><\/p>\n

      2.Concepts of Space and time in Spatial Information Systems<\/strong><\/span><\/p>\n

      \u00a0<\/strong><\/span><\/p>\n

      \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/strong>Spatial information is always related to geographic space, i.e., large-scale space.\u00a0 This is the space beyond the human body, space that represents the surrounding geographic world.\u00a0 Within such space, we constantly move around, we navigate in it, and we conceptualize it in different ways.\u00a0 Geographic space is the space of topographic, landuse\/landcover, climatic, cadastral, and other features of the geographic world.\u00a0 Geographic information system technology is used to manipulate objects in geographic space, and to acquire knowledge from spatial facts.<\/span><\/p>\n

      Geographic space is distinct from small-scale space, or tabletop space.\u00a0 In other words, objects that are smaller than us, objects that can be moved around on a tabletop, belong to small-scale space and are not subject of our interest.<\/span><\/p>\n

      The human understanding of space, influenced by language and cultural background, plays an important role in how we design and use tools for the processing of spatial data. In the same way as spatial information is always related to geographic space, it relates to geographic time, the time whose effects we observe in the changing geographic world around us.\u00a0 We are less interested in pure philosophical or physical considerations about time or space-time, but more in the observable spatio-temporal effects that can be described, measured and stored in information systems.<\/span><\/p>\n

      \u00a0<\/span><\/p>\n

      <\/a><\/a><\/a><\/a>Spatial information systems<\/strong><\/span><\/p>\n

      The handling of spatial data usually involves processes of data acquisition, storage and maintenance, analysis and output.\u00a0 For many years, this has been done using analogue data sources, manual processing and the production of paper maps.\u00a0 The introduction of modern technologies has led to an increased use of computers and information technology in all aspects of spatial data handling.\u00a0 The software technology used in this domain is geographic information systems (GIS).<\/span><\/p>\n

      A general motivation for the use of GIS can be illustrated with the following example.\u00a0 For a planning task usually different maps and other data sources are needed.\u00a0 Assuming a conventional analogue procedure we would have to collect all the maps and documents needed before we can start the analysis.\u00a0 The first problem we encounter is that the maps and data have to be collected from different sources at different locations (e.g., mapping agency, geological survey, soil survey, forest survey, census bureau, etc.), and that they are in different scales and projections.\u00a0 In order to combine data from maps they have to be converted into working documents of the same scale and projection.\u00a0 This has to be done manually, and it requires much time and money.<\/span><\/p>\n

      With the help of a GIS, the maps can be stored in digital form in a database in world co-ordinates (meters or feet).\u00a0 This makes scale transfor\u00admations unnecessary, and the conversion between map projections can be done easily with the software.\u00a0 The spatial analysis functions of the GIS are then applied to perform the planning tasks.\u00a0 This can speed up the process and allows for easy modifications to the analysis approach.<\/span><\/p>\n

      <\/a><\/a><\/a><\/a>GIS, spatial information theory, and the Geoinformatics context<\/strong><\/span><\/p>\n

      Spatial data handling involves many disciplines.\u00a0 We can distinguish disciplines that develop spatial concepts, provide means for capturing and processing of spatial data, provide a formal and theoretical foundation, are application-oriented, and support spatial data handling in legal and management aspects.\u00a0 The following Table shows a classification of some of these disciplines.\u00a0 They are grouped according to how they deal with spatial information.\u00a0 The list is not <\/span><\/p>\n

      meant to be exhaustive.<\/span><\/p>\n

      \"01\"<\/a><\/span><\/p>\n

      \n

      The discipline that deals with all aspects of spatial data handling is called Geoinformatics.\u00a0 It is defined as:<\/span><\/p>\n

      \"02\"<\/a><\/span><\/p>\n

      \n

      Geoinformatics has also been described as \u201cthe science and technology dealing with the structure and character of spatial information, its capture, its classi\u00adfication and qualification, its storage, processing, portrayal and dissemination, including the infrastructure necessary to secure optimal use of this information\u201d (Groot, 1989).\u00a0 Ehlers and Amer (1991) define it as \u201cthe art, science or technology dealing with the acquisition, storage, processing production, presentation and dis\u00adsemination of geoinformation.\u201d<\/span><\/p>\n

      A related term that is sometimes used synonymously with geoinformatics is geomatics.\u00a0 It was originally introduced in Canada, and became very popular in French speaking countries.\u00a0 Laurini and Thompson (1992) describe it as \u201cthe fusion of ideas from geo-sciences and informatics.\u201d\u00a0 The term geomatics, however, was never fully accepted in the United States where the term geographical information science is preferred.\u00a0 Goodchild (1992) defines GIS research as \u201cresearch on the generic issues that surround the use of GIS technology, impede its successful implementation, or emerge from an understanding of its potential capabilities.\u201d<\/span><\/p>\n

      \u00a0\u00a0\u00a0\u00a0 There is no clear-cut definition for GIS. Different people defined GIS according to capability and purpose for which it is applied. Few of the definitions are:<\/span><\/p>\n