Scientific- Research Quarterly of Geographical Data (SEPEHR)

Precise Geological Mapping as a New Method for Analyzing Surface Faults

Mahdi Modiri

Volume 17, Issue 67 , October 2008, , Pages 2-12

Abstract

  In order to evaluate the potential for earthquake surface fracture, a new application of highly accurate geological mapping with total electronic station is presented. This method makes it possible to detect secondary faults, which represent 30-cm-long vertical displacement that does not appear on the ...  Read More In order to evaluate the potential for earthquake surface fracture, a new application of highly accurate geological mapping with total electronic station is presented. This method makes it possible to detect secondary faults, which represent 30-cm-long vertical displacement that does not appear on the surface. These very small faults do not have signs and symptoms of topology, so it is likely that they will not be considered though they show the existence of faults in the range of installations and movements. This method involves mapping of points in geological features and accurate and comprehensive analysis of computer details and field operations of abnormalities at the heights of mapped points. General abnormalities are considered at high altitudes that are mainly consisting of normal and inverted fault. However, this method can be used for longitudinal slip faults as well. This method provides the conditions where geological data can easily be integrated into GIS and 3D analysis of details of small structure features can be achieved; field data can be analyzed in the profiles of three dimensional diagrams and in maps that are made using cartographic software. The ability of this method to identify faults with slight displacement allows the types of metamorphism, reduction in displacement of the direction of small and divergent faults, located at the two extremities of large and ordinary faults, single-slope bends and transverse structures between faults can be determined.

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Automatic Vectorization of Cartographic Maps by a Science-Based System

Mahdi Modiri

Volume 17, Issue 66 , August 2008, , Pages 2-13

Abstract

  The evolution and progress of the automatically vectorizing system is very important as a process input method that takes great time and cost. Most systems that vectorize roster data will force users to set different parameters for a particular map image. But it is difficult for novices to be able to ...  Read More The evolution and progress of the automatically vectorizing system is very important as a process input method that takes great time and cost. Most systems that vectorize roster data will force users to set different parameters for a particular map image. But it is difficult for novices to be able to modify the parameters properly and appropriately. This paper explains a science-based system in order to achieve the automatic vectorization of roster information. This automatic system makes the right choice of parameters possible. Since the act of limiting input image data to produce a framework of proper length and width is a necessary condition for the automatic vectorization of roster data in several steps, so the implementation of limiting algorithms for sample data is systematically evaluated in the images of multiple map, and appropriate rules for maps are thus formed.

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Investigation of Cartographic Techniques in Establishing Proper Visual Communication (Computer Display)

Mahdi Modiri

Volume 17, Issue 65 , May 2008, , Pages 2-10

Abstract

  The method discussed in this paper can help the designer to display information in a conceptual way by using computer color code, as the method of the effect of visual colors used in cartography. Principles and foundations of color and cartography are used to prepare color tables (pattern). Colors within ...  Read More The method discussed in this paper can help the designer to display information in a conceptual way by using computer color code, as the method of the effect of visual colors used in cartography. Principles and foundations of color and cartography are used to prepare color tables (pattern). Colors within the color tables (pattern) are coded and based on information such as display elements, which is more appropriate to the user's specialty. The application of this method leads to establishment of an optimal visual connection between user and computer display.

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Spatial Analysis of Clustering Based on Genetic Algorithm

Mahdi Modiri

Volume 17, Issue 68 , February 2008, , Pages 2-8

Abstract

  In order to conduct spatial analysis of clustering, the principles and characteristics of genetic algorithms are utilized. The present paper presents a new method of spatial analysis of clustering based on genetic algorithm. The results of the scientific and practical experiments show that this method ...  Read More In order to conduct spatial analysis of clustering, the principles and characteristics of genetic algorithms are utilized. The present paper presents a new method of spatial analysis of clustering based on genetic algorithm. The results of the scientific and practical experiments show that this method can maintain the overall characteristic of distribution and obtain an appropriate result.

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Map With Variable Scale (1) on Small Cartograms

Mahdi Modiri

Volume 16, Issue 64 , February 2008, , Pages 2-7

Abstract

  This research is devoted to the development of methods for presenting instant geographical and positional information on personal computers for moving users, specially users who need to carry a comprehensive map with them to find the main paths they need. On the other hand, the user needs a small scale ...  Read More This research is devoted to the development of methods for presenting instant geographical and positional information on personal computers for moving users, specially users who need to carry a comprehensive map with them to find the main paths they need. On the other hand, the user needs a small scale map in order to reach the final destination on the path. A solution that is intended to fulfil this practical need in maps is to create a variable-scale map, so that this map changes scales continuously in order to find the user's position, and must first be set within the range of large scales. Regarding the relations used for a variable-scale map, the explanation of characteristics of these relations are discussed.  The importance of the article and the extension of research shows that variable-scale maps have many advantages in personal computers and mobile systems such as mobile phones.

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Geosciences in the Pursuit of Information Technology (introduction to spatial analysis ) Part I

Mahdi Modiri

Volume 16, Issue 63 , November 2007, , Pages 2-10

Abstract

  The spatial pattern is of great importance for the Earth sciences. The spatial pattern enables us to compare the observational characteristics of phenomena and to clarify their spatial relationship, correlation and distribution in terms of geological conditions and processes that have shaped them. Digital ...  Read More The spatial pattern is of great importance for the Earth sciences. The spatial pattern enables us to compare the observational characteristics of phenomena and to clarify their spatial relationship, correlation and distribution in terms of geological conditions and processes that have shaped them. Digital cartography and spatial model provide computer support for the observation of phenomena and characteristics in their spatial texture. Transitions make it possible that phenomena have movement and shape in order to gain better visualization and analysis. Space statistics have the ability to numerically determine the configuration for the purpose of form and structure analysis.

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Models and Search in a Spatial-Temporal GIS

Mahdi Modiri

Volume 16, Issue 62 , August 2007, , Pages 2-13

Abstract

  Recently, a tendency toward the combined implementation of space-time information on extended spatial bases has emerged. In geographic information systems and other sciences, studies are conducted in different fields of space-time display and argumentation. Creating a Temporal Geographic Information ...  Read More Recently, a tendency toward the combined implementation of space-time information on extended spatial bases has emerged. In geographic information systems and other sciences, studies are conducted in different fields of space-time display and argumentation. Creating a Temporal Geographic Information System (TGIS) leads to a system that is capable of plotting, displaying and analyzing various study areas, storing specific geographic features, and forecasting future characteristics. A Temporal Geographic Information System (TGIS) can be used to identify the steps that cause geographic changes, and connect the various stages of obtaining different data patterns. The main themes of this paper are the development of TGIS, determination of conceptual models and modeling structures. In a TGIS system, several methods for conceptual modeling are proposed. In the past, these methods were performed according to the intended type of search. In fact, questions such as "What?", "Where?" And "When?" were categorized according to space, (land) feature and event (Peuquest and Dauan). Other classifications of these methods are also determined by the tools used in modeling, such as diagrams of symbols relationships, semantic models, orientations ... This article is a comprehensive examination of the various points of view associated with GIS.

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Remote Geographic Information Control and Process

Mahdi Modiri

Volume 16, Issue 61 , May 2007, , Pages 2-9

Abstract

  The purpose of this paper was to determine the characteristics of remote processing and control systems of geographic information. The processing of geographical information is the product of GIS and telecommunications. Remote geographic information processing is a completely new approach designated ...  Read More The purpose of this paper was to determine the characteristics of remote processing and control systems of geographic information. The processing of geographical information is the product of GIS and telecommunications. Remote geographic information processing is a completely new approach designated by spatial (position) databases, exchange of information at various sites, and continuous and simultaneous analysis of spatial and non-spatial data. Geographic information control can also be carried out using global positioning systems (GPS), databases and instantaneous decision-making systems (crisis headquarters).

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An Introduction to Geographic Information System (GIS) at the National Level

Mahdi Modiri

Volume 15, Issue 59 , November 2006, , Pages 2-5

Abstract

  Information systems have been created for certain purposes, so they must first fulfil specific mission and tasks, and then be able to support real affairs. In this paper, we will attempt to propose reasons to support the notion that GIS should not be considered as an exception among information systems, ...  Read More Information systems have been created for certain purposes, so they must first fulfil specific mission and tasks, and then be able to support real affairs. In this paper, we will attempt to propose reasons to support the notion that GIS should not be considered as an exception among information systems, and to explain how geographic information can be re-used.

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Access to Comparative Examination of Geographic Information in Electronic Space

Mahdi Modiri

Volume 15, Issue 58 , August 2006, , Pages 2-5

Abstract

  In this paper, we use the Theory of Information Sciences and its application in the World Wide Web (WWW) in order to study the ways of access to geographic information. The two main information retrieval systems include data and information retrieval. A data retrieval system includes retrieval models, ...  Read More In this paper, we use the Theory of Information Sciences and its application in the World Wide Web (WWW) in order to study the ways of access to geographic information. The two main information retrieval systems include data and information retrieval. A data retrieval system includes retrieval models, indexing, matching and retrieval, linking, sorting, search time and determining the method of search. The main purpose of information retrieval is to match the needs of users to information within the system. GIS retrieval is a combination of data and information retrieval. The language of search uses signs and natural language, automatic indexing of geographical information and standardization of geographic information. Geographic Information Retrieval Systems (GIRS) can be viewed on the World Wide Web (WWW).

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Inverse Numerical Transmission in Map Image Systems

Mahdi Modiri

Volume 15, Issue 57 , May 2006, , Pages 2-8

Abstract

  In cartography, mapping systems are used to transfer geographic coordinates to planar coordinate network. This method is called "forward transmission". In many applications, including Geographic Information Systems (GIS), maps are digitized using digitizers. Therefore, the data collected are integrated ...  Read More In cartography, mapping systems are used to transfer geographic coordinates to planar coordinate network. This method is called "forward transmission". In many applications, including Geographic Information Systems (GIS), maps are digitized using digitizers. Therefore, the data collected are integrated into another set of data, in which case the planar coordinates should be transmitted into the form of geographical coordinates; this is called “Inverse Transmission”. In this paper, two numerical methods for inverse transmission are discussed.

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Sepehr's Achievement

Mahdi Modiri

Volume 15, Issue 60 , February 2006, , Pages 2-25

Abstract

  Many of sciences undergo constant transformation through connection with modern technology and make progress, and are provided with equipment of great value through ease in the methods and fast fulfilment of necessities. The science of cartography, under the influence of modern technology (positioning ...  Read More Many of sciences undergo constant transformation through connection with modern technology and make progress, and are provided with equipment of great value through ease in the methods and fast fulfilment of necessities. The science of cartography, under the influence of modern technology (positioning and imagery satellites, databases and digital systems, etc.), has undergone a radical and extensive development. The reliance on "modeling" is a world of constructive relationships between geomatic technologies and sciences in applications. Creating spatial and geographical database presents a smart product for different sciences that provides the ability to determine, identify, organize, combine, display and manage information. In geographic information system environment, the arrangement, combination and visualization of different ways of implementation of a geographic position can be carried out using the power of automatic computer sampling in a proper way.  The visualization of data in a geographic system environment places the user in logical decision-making conditions. Because in this environment, it is possible to store separate pieces of geographic space in the form of point, line, surface, and text records that make up the final composition of all elements and geographic phenomena, and, if needed, to display them in one place in the form of a single image, and most importantly, if necessary, to connect their contents to each other. Components of images taken from the real world are carefully recorded in the memory of computer with a special character encoding. This type of data helps users place images and objects together in a regular, meaningful and organized way in a geographic space. Creating spatial database is a platform for creation of intelligent information that helps users in understanding, analysis, and proper decision-making. On the basis of a spatial database, geographic data can be increased and geographic information systems formed, and the more various qualitative and quantitative characteristics associated with spatial features, the higher the level of intelligence of database. Several organizations are seeking to publish their spatial and geographical information using the Web GIS so that different users, such as decision makers and planners, can access this information regardless of time and place constraints. Web GIS is a spatial and geographic information system distributed in a computer network used to integrate and disseminate graphic information on the WWW and on the Internet.

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Cartography and Automation

Mahdi Modiri

Volume 14, Issue 55 , November 2005, , Pages 2-6

Abstract

  How is the relationship between automation and cartography? What is the effect of automation on cartography? What is the achievement of automation in cartography? Each of the human sciences has, through connection with modern technology, made great achievements in terms of ease of use, speed, application, ...  Read More How is the relationship between automation and cartography? What is the effect of automation on cartography? What is the achievement of automation in cartography? Each of the human sciences has, through connection with modern technology, made great achievements in terms of ease of use, speed, application, access to great deal of knowledge and vast advances. The science of cartography, influenced by modern technology and automation, has undergone a fundamental change, and has grown in terms of dimensions, scope of influence and number of applications. The relationship of automation with cartography:  The computer's entry into cartography has found its true form in a 50-year-old process. The first successful attempt to exploit the computer to produce a map goes back to the early 1950s. The utilization of computer techniques in production of cartographic works took place in the mid-1970s, and it reached a stage in the late 1980s that it could replace a large part of classic cartography.

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Cartography and the Internet (Part V)

Mahdi Modiri

Volume 14, Issue 54 , August 2005, , Pages 2-11

Abstract

  In order to describe the generalization process for classes of selective phenomena, we describe the sequence and probable order and determine which operators and generalization algorithms will be used. The generalization operator specifies the type of "generalization" conversion that must be applied, ...  Read More In order to describe the generalization process for classes of selective phenomena, we describe the sequence and probable order and determine which operators and generalization algorithms will be used. The generalization operator specifies the type of "generalization" conversion that must be applied, then the generalization algorithm is used to implement a particular conversion. In the presentation of the characteristics report a series of covering maps of Switzerland is used.

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Cartography and the Internet: Part IV

Mahdi Modiri

Volume 14, Issue 53 , May 2005, , Pages 2-10

Abstract

  This paper describes map’s generalization according to different needs of users by using a multi-scale database. The base of such production is the analysis of the maps’ requirements according to users’ demands, and indicates various needs and limitations of the cartography demanded ...  Read More This paper describes map’s generalization according to different needs of users by using a multi-scale database. The base of such production is the analysis of the maps’ requirements according to users’ demands, and indicates various needs and limitations of the cartography demanded by the user. The main basis of this examination is the combination of two cartographic attitudes:1. Utilization of multi-scale database which includes two or more levels of details; and2. Using cartography generalization methods.This paper has been designed and conducted for selective topics (information classification) and discusses and analyzes implementation of choices of multi-scale database and generalization of parts of framework. The importance lies in optimal combination of these two methods, namely matters that are resolved by multi-scale database, as well as actions that must be performed through generalization process.

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Cartography, GIS and the World Wide Web

Mahdi Modiri

Volume 14, Issue 56 , February 2005, , Pages 2-6

Abstract

  Based on initial architecture, the World Wide Web is a collection of human knowledge that allows users to exchange ideas and suggestions among distant places. Cartography and Geographic Information Systems (GIS) are in the early stages of development, considering the characteristics of spatial and geographical ...  Read More Based on initial architecture, the World Wide Web is a collection of human knowledge that allows users to exchange ideas and suggestions among distant places. Cartography and Geographic Information Systems (GIS) are in the early stages of development, considering the characteristics of spatial and geographical information. Currently, the Web provides access to various forms of land features’ information in the form of maps, aerial and satellite imagery, sound and text, so that they can be linked to other related information. The World Wide Web is also designed to connect any land feature’s information to that of other land features. As a result, the Web has the potential for ease of change in cartography and GIS through three basic mechanisms: 1 - By increasing its application in mapping and GIS and providing greater access to tools and data, 2. By combining non-spatial information technology, GIS and production of combined maps (spatial and non-spatial), and 3. By establishing a virtual world and testing models and visualization that should be designed, analyzed and interpretable.

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Remote Sensing and Geographic Information Systems (RS & GIS) (Part IV)

Mahdi Modiri

Volume 13, Issue 51 , November 2004, , Pages 2-4

Abstract

  Geographic information can be digitized in vector format and processed and transformed by satellite data (visual information) in a raster environment. Such systems are beneficial, but it should be noted that multiple transformations of vector and raster data will be carried out losing accuracy and at ...  Read More Geographic information can be digitized in vector format and processed and transformed by satellite data (visual information) in a raster environment. Such systems are beneficial, but it should be noted that multiple transformations of vector and raster data will be carried out losing accuracy and at the expense of data degradation.A combination enables the processing of two vector and raster structures, hierarchical representation, and object-oriented search for remote sensing data to a fairly full extent.Satellite image analysis has the ability to combine and integrate one or more remote sensing models. Models are divided into empirical as against algebraic models, and invertible versus non-invertible models. Empirical models have reliance on linkage, sensor measurements and surface properties, while algebraic models rely on the heat and radiation transfer hypothesis. Models with inverse capability are those in which unknown properties of the landscape can be deduced from the measurements of remote sensing.

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Remote Sensing and Geographic Information Systems (RS & GIS) Part III

Mahdi Modiri

Volume 13, Issue 50 , August 2004, , Pages 2-7

Abstract

  The conversion of satellite data into vector formats requires classification and interpretation of low-level information while maintaining accuracy of measurement and spatial detail; on the other hand rasterizing a map (which is consistent with satellite data) means decomposition and degradation of high-level ...  Read More The conversion of satellite data into vector formats requires classification and interpretation of low-level information while maintaining accuracy of measurement and spatial detail; on the other hand rasterizing a map (which is consistent with satellite data) means decomposition and degradation of high-level cartographic information. Therefore, in combining and integrating image and cartographic data in a data structure, such exchanges should be considered.

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Geomatic Engineering and Geographical Sciences

Mahdi Modiri

Volume 13, Issue 49 , May 2004, , Pages 1-5

Abstract

  Geomatic Engineering and sciences include activities that involve obtaining (receiving, collecting, deducing and utilizing), processing (networking, scaling, computing, topological structure and simulation), analysis, display (topography, two-dimensional, three dimensional and animation display) and ...  Read More Geomatic Engineering and sciences include activities that involve obtaining (receiving, collecting, deducing and utilizing), processing (networking, scaling, computing, topological structure and simulation), analysis, display (topography, two-dimensional, three dimensional and animation display) and spatial information management (modeling and exploitation). Geosciences are not limited to geodesy, photogrammetry, mapping, cartography, geographic information systems (GIS) and cadastre, but include a wide range of environmental and spatial sciences with a variety of career opportunities. The widespread applications of engineering and geomatic sciences demand widespread theoretical and applied research. Geomatic specialists utilize information collection techniques (such as digital imaging and satellite positioning) and advanced computer systems. They play a major role in providing visualization and effective assistance in decision making, and in implementation and control of all construction over, under and above the ground in the following projects. • Design, construction and management of urban engineering projects• Obtaining (collecting and utilizing) information and production of maps and digital charts• Asset management such as land, transport infrastructure and property (by GIS, LIS)• Control of environmental changes and natural resource management (through remote sensing)• Urban planning• Earthquake prediction (through measurements of very slow motion of the Earth),• Control of the safety of various structures, such as stairs, dams, large buildings and towers.• Exploration and engineering for production of gas and oil in different areas• Measuring and controlling sensitive areas

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Documentation of Cartographic Sources (Part II)

Mahdi Modiri

Volume 13, Issue 52 , February 2004, , Pages 2-11

Abstract

  Innovations in technology take place when new methods replace current techniques. The initial stage is usually limited to something that can be called "modernization." It may take some time before the next step is implemented and results of new applications are evaluated and understood. It may take a ...  Read More Innovations in technology take place when new methods replace current techniques. The initial stage is usually limited to something that can be called "modernization." It may take some time before the next step is implemented and results of new applications are evaluated and understood. It may take a long time before organizational structure and procedures are adapted to an innovation, and even more time may be needed before theoretical and cognitive consequences are realized. After the new concepts are combined with methods following practical applications, real success will be achieved. Only then is the implementation of modern technology at its full potential and its practice optimized.  The MARC Project of the Library of Congress is designed for exchange of bibliographic information in a form readable by computer. The purpose of the system’s design is to reduce the costs of distributing the card catalogs amongst the library community. The system was later used for advanced work such as information retrieval system and listing.

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Remote Sensing and Geographic Information Systems (RS & GIS) (Part I)

Mahdi Modiri

Volume 12, Issue 47 , November 2003, , Pages 2-6

Abstract

  Remote sensing is important as a new technology for collection of geographic data for GIS on the one hand and as user's reference spatial data for scientific analysis on the other. In this paper, emphasis is placed on the importance of linking remote sensing raster data to GIS vector data to create IGIS. ...  Read More Remote sensing is important as a new technology for collection of geographic data for GIS on the one hand and as user's reference spatial data for scientific analysis on the other. In this paper, emphasis is placed on the importance of linking remote sensing raster data to GIS vector data to create IGIS. The application of IGIS is of great value in a variety of applications, such as information classification and environmental modeling. It is evident that remote sensing and IGIS complement each other, and both progressed independently and separately, especially in the early days. With linking the technology, concepts and theories of both in IGIS, more advanced and up-to-date information systems can be created for use in real applications. Almost all projects that currently use satellite data or deal with environmental data benefit from development of IGIS.

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Documentation of Sources of Cartography- Part I

Mahdi Modiri

Volume 12, Issue 46 , August 2003, , Pages 2-9

Abstract

  Cartographers deal with aspects of documentation that follow a series of current practices and methods based on logic and conventions. Documentation and information both play important roles in the process of knowledge transfer. Information provides details about documents (primary sources and documents) ...  Read More Cartographers deal with aspects of documentation that follow a series of current practices and methods based on logic and conventions. Documentation and information both play important roles in the process of knowledge transfer. Information provides details about documents (primary sources and documents) and items they include. At the moment, the term “super information” or information about information is a common term in the world of computerized information communication, and can be equivalent to documenting.

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What is Map Projection?

Mahdi Modiri

Volume 12, Issue 45 , May 2003, , Pages 2-8

Abstract

  The earth is spherical, or in a better estimation, spheroid (pseudo-sphere) or elliptical. A map should represent the 3D land on a two-dimensional surface as accurate as possible.In producing maps, it is important that we achieve a clear and distinguished relationship between realities on the Earth and ...  Read More The earth is spherical, or in a better estimation, spheroid (pseudo-sphere) or elliptical. A map should represent the 3D land on a two-dimensional surface as accurate as possible.In producing maps, it is important that we achieve a clear and distinguished relationship between realities on the Earth and corresponding points on the map. Therefore, making any map must start with a map projection system. There are dozens of map projection systems that one can choose from among. The systematic and orderly process of transferring points from spherical surface of the earth to a flat surface (map) in a way that spatial relationships are preserved is called a map projection system. The process of map projection system is implemented through application of geometry and mathematical relations. In terms of geometric concepts, the earth is a spheroid (pseudo-spheroid) which is slightly compressed.According to another definition, the mapping of the meridian and the earth's orbits as a network called the Geographic Coordinate Network on a flat surface is called the map projection system.

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Remote Sensing and Geographic Information Systems (Part II)

Mahdi Modiri

Volume 12, Issue 48 , February 2003, , Pages 2-8

Abstract

  Satellite sensors provide the opportunity for continuous multi-time measurements of a vast area over a period of several days to several decades. Sensor coverage and distance repetition are determined by the height of the shooting platform (satellite), angular acceleration, orbital inclination in proper ...  Read More Satellite sensors provide the opportunity for continuous multi-time measurements of a vast area over a period of several days to several decades. Sensor coverage and distance repetition are determined by the height of the shooting platform (satellite), angular acceleration, orbital inclination in proper relation to the equator, and determining the position in proper relation to spring equinox (Elachi, 1987).Many optic sensors have been deployed in near-polar solar synchronous orbits so that global coverage and geometry of continuous light can be achieved. The distance repetition between sensors is different because it depends on the elevation and acceleration of sensors.Other sensors have been placed in the Earth's synchronous orbit so that a high coverage frequency can be obtained from that area. (For example, GEOS meteorological satellites)The ability to detect changes in the surface area photographed over time depends on the recording of spatial geometry and spatial resolution, spectral width and spectral band location, and the radiometric and temporal properties of the sensor imagery frequency. Comparison of received images by a sensor in different dates with any variations in deviation of measuring device and the difference in atmospheric characteristics, is particularly complicated in the secondary pixel cloud coverage.Detection change is considerably more complicated when more than a sensor system is used due to differences between IFOV and PSF sensors, and in bandwidth and spectral response properties.

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Satellite Information - Part I

Mahdi Modiri

Volume 11, Issue 43 , November 2002, , Pages 2-6

Abstract

  One of the fastest ways to collect geographic data is satellite imaging. Based on technical specifications and capabilities of an imaging system on a space platform (satellite), it is possible to collect geographic data with different geometric precision and resolution.The first satellite imagery with ...  Read More One of the fastest ways to collect geographic data is satellite imaging. Based on technical specifications and capabilities of an imaging system on a space platform (satellite), it is possible to collect geographic data with different geometric precision and resolution.The first satellite imagery with cartographic application was prepared by a metric camera, followed by Kosmos (Russia), Landsat (USA) and Spot (France) series of satellites which, equipped with imaging systems adapted to mapping conditions (incl. stereo coverage, metric or central system, high feature-resolution, etc.), have gained a solid place in geomatic sciences and technology regarding geometric collection of geographic data and extraction of accurate and correct information. Today IRS satellites have gained a strong position by an orderly program of providing cartographic images. The author has, from time to time through various investigations and implementation of research and practical projects, presented to the students in the field discussions on principles of remote sensing, applications of remote sensing in urban constructions, remote sensing and geographic information systems, platforms and imaging sensors (optical and scanner systems) in the form of papers in this journal or books. It seems proper to open a new series of discussions on satellite imaging systems of India and to provide a brief overview of Indian space programs and images with diverse applications in science and technology.

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