Scientific- Research Quarterly of Geographical Data (SEPEHR)

Cartography and the Internet - Part III

Mahdi Modiri

Volume 11, Issue 42 , August 2002, , Pages 2-7

Abstract

  The Internet is a very important tool that has had a major role in receiving and disseminating information over the past few years. The Global Communication Network delivers and disseminates most of the recent news concerning geographic data. In this process, maps play a pivotal role and has a multi-purpose ...  Read More The Internet is a very important tool that has had a major role in receiving and disseminating information over the past few years. The Global Communication Network delivers and disseminates most of the recent news concerning geographic data. In this process, maps play a pivotal role and has a multi-purpose function. Maps can play their historical role in providing information for geographic plans and their necessary conditions. The main focus of the expansion of utilization is through the World Wide Web Group (WWW), and some problems regarding the supply of cartographic information have emerged as a result of this development. The most important issues are:- A wide variety of uncertain user environments- Uncertain Web Links (Connections)

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Preparation of Electronic Images

Mahdi Modiri

Volume 11, Issue 41 , May 2002, , Pages 2-5

Abstract

  Video recording is a form and state of electronic image recording in which standard analogue television signals are recorded on a magnetic tape or disk. Cameras used for video recording of aerial images include: single-band, multi-band or multi-single-band cameras. These cameras can read visible wavelengths, ...  Read More Video recording is a form and state of electronic image recording in which standard analogue television signals are recorded on a magnetic tape or disk. Cameras used for video recording of aerial images include: single-band, multi-band or multi-single-band cameras. These cameras can read visible wavelengths, near-infrared, and half-infrared (not all cameras cover this full range). For example, figure (1) shows a multi-band video camera that is sensitive to green, red and near-infrared wavelengths, and models the spectral response of colored infrared images.

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Digital Photogrammetry, Transformation or Advance

Mahdi Modiri

Volume 11, Issue 44 , February 2002, , Pages 2-4

Abstract

  In the course of the evolution of surveying from “the science of mapping” to “the visualization of geographic data”, the surveyor has always had his/her eyes on "simulation", and his/her reliance on daily achievements of technology, education and experience has been aimed at making ...  Read More In the course of the evolution of surveying from “the science of mapping” to “the visualization of geographic data”, the surveyor has always had his/her eyes on "simulation", and his/her reliance on daily achievements of technology, education and experience has been aimed at making maps of more resemblance to the earth. The transformation is due to integration of cartography, photogrammetry and digital field. Relying on "modeling" is a world of constructive connections between science and surveying technology in applications. Model is what should be created and modeling is design for the future. The model is displayed based on processed geographical data, and therefore Modeling is developed with digital photogrammetry and computer cartography. Photogrammetry is a necessary and effective science for obtaining spatial data and has vast applications in engineering and industry. In photogrammetry, fundamental changes were made from the analogue to the digital stage. Digital photogrammetry has an enormous potential to offer abilities and benefits.

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Cartography and the Internet - Part II

Mahdi Modiri

Volume 10, Issue 39 , November 2001, , Pages 2-5

Abstract

  Graphics such as maps, aerial photos and satellite images have become an integral part of the web. One of the reasons for this is reducing the cost of distribution and presentation, because putting color graphics on the web is much cheaper than color printing on paper. When we consider the extra shipping ...  Read More Graphics such as maps, aerial photos and satellite images have become an integral part of the web. One of the reasons for this is reducing the cost of distribution and presentation, because putting color graphics on the web is much cheaper than color printing on paper. When we consider the extra shipping and distribution costs for print products, we will realize that distributing maps and images over the Internet is cost-effective. However, printing maps has advantages that cannot be ignored, including very suitable print resolution (the high resolution print has a resolution of 1200 to 3400 dots per inch or 472 to 1339 dots per centimeter). On the other hand, computer screen can only have a precision of 65 to 120 dpi (25.6 to 47.2 dots per centimeter). Computer screen has limitations in terms of screen dimensions: the standard screen size ranges from 14 inches to 21 inches, while maps, photos and prints can be made at much larger cuts.

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Cartography and the Internet - Part I

Mahdi Modiri

Volume 10, Issue 38 , August 2001, , Pages 2-7

Abstract

  Currently, there are many computer sites that make maps accessible to users all over the world. The main reasons for their increasing expansion are:• Reduction of cost (distribution of color graphics such as maps by computer sites costs far less than printing and distributing maps on paper)• ...  Read More Currently, there are many computer sites that make maps accessible to users all over the world. The main reasons for their increasing expansion are:• Reduction of cost (distribution of color graphics such as maps by computer sites costs far less than printing and distributing maps on paper)• Reduction of transmission time (maps that are put on computer networks can be transmitted over a short period of time (not exceeding a few seconds) to users anywhere in the world)• Enhancing abilities (it makes interaction between GIS and users possible, so that full conversational conditions are achieved.)• Extensive use (Computer map provides users with a wide range of applications for maps)• GIS (Cartographic Information System provides basic information and topological structure of various data in the GIS “Geographic Information System”).

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Thematic Index of the Sepehr Journal

Mahdi Modiri

Volume 10, Issue 37 , May 2001, , Pages 2-16

Abstract

  Today there is rarely any applied science or branch of activity on earth that has no need to understanding the environment, geographic position and natural conditions and potentials. Geographic information is the most important decision-making tool in different activities on earth.The knowledge of mapping ...  Read More Today there is rarely any applied science or branch of activity on earth that has no need to understanding the environment, geographic position and natural conditions and potentials. Geographic information is the most important decision-making tool in different activities on earth.The knowledge of mapping (surveying, remote sensing, and geographic engineering) has benefited from the blessings of the glorious Islamic Revolution more than any other science. The dramatic changes and advances that have been made in earth sciences in recent years have been influenced by the need for quick and accurate access to better understanding of the land and potentials of the country in the field of defense and developmental construction.  

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Impact of Geometric Factors on Film Exposure

Mahdi Modiri

Volume 10, Issue 40 , February 2001, , Pages 2-6

Abstract

  The images are formed through the change in the strength of brightness of the scene upon the film. At first glance, in aerial photography such changes are related only to the change in the type of the land feature. Of course, this hypothesis is an over-simplification of the issue, because there are many ...  Read More The images are formed through the change in the strength of brightness of the scene upon the film. At first glance, in aerial photography such changes are related only to the change in the type of the land feature. Of course, this hypothesis is an over-simplification of the issue, because there are many factors that are not related to the type or conditions of a land feature and can affect the measurements of the exposure value of the film. Since the above-mentioned factors affect the measurement of exposure but do not play a role in the true changes of the type of land cover due to conditions, they are called "external effects". Here, the major geometric effects that affect the exposure of the film are discussed.

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Aerial Images

Mahdi Modiri

Volume 9, Issue 35 , November 2000, , Pages 2-3

Abstract

  Photography is one of the main means of transmission of information and collection of geographic data with wide applications, and aerial photography and remote sensing are the most common ways of quick access to geographic information remotely. - Better understanding of land by viewing and interpreting ...  Read More Photography is one of the main means of transmission of information and collection of geographic data with wide applications, and aerial photography and remote sensing are the most common ways of quick access to geographic information remotely. - Better understanding of land by viewing and interpreting aerial and space images; - Identification of natural and artificial phenomena and features and their geometric measurement; - Introduction of geographic factors of the formation, development and expansion of cities; - and the production of aerial photos and their conversion into topographic and thematic maps are among the applications of aerial photography in the earth sciences, especially surveying and geography. Aerial photography is the most economical way to access geographic information remotely. Aerial photography, due to its many advantages, is one of the most efficient methods of collecting geographic information that has certain advantages compared to terrestrial observations (terrestrial surveying). The most important of such features are addressed here.

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Analytical Photogrammetry System

Mahdi Modiri

Volume 9, Issue 34 , August 2000, , Pages 2-5

Abstract

  It is now more than thirty years since the important parts of photogrammetry have been automated. One of the primary applications of photogrammetric automation is to digitize the data of the device's measurement system using the numerical stability system. In general, the coordinates of automatic drawings ...  Read More It is now more than thirty years since the important parts of photogrammetry have been automated. One of the primary applications of photogrammetric automation is to digitize the data of the device's measurement system using the numerical stability system. In general, the coordinates of automatic drawings are used by converting devices (the photo-mapping converting system). This device receives the order through a computer, which receives the commands and coordinates of the model’s points from the machine and transmits them to this device. The set of encoders, the servomotor system, and the computer with a stereocomparator make up the analytical photogrammetric system.

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Electronic (Digital) Photography

Mahdi Modiri

Volume 9, Issue 34 , August 2000, , Pages 24-27

Abstract

  In aerial surveying, the process of image preparation (aerial photography) using aerial cameras and photographic film for recording and storing photos is the most important artistic and validating technical stage in different activities concerning map preparation which is still utilized in various applications ...  Read More In aerial surveying, the process of image preparation (aerial photography) using aerial cameras and photographic film for recording and storing photos is the most important artistic and validating technical stage in different activities concerning map preparation which is still utilized in various applications in map production and analysis. Today preparation of electronic image, through basic changes in method of photography and exploitation of electronic photography systems, brings about a transformation in aerial surveying, which is gradually embedded in the process of operation.

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Global Positioning System (GPS)

Mahdi Modiri

Volume 9, Issue 33 , May 2000, , Pages 2-4

Abstract

  Positioning based on satellite systems began in early 1961. GPS was evolved over time with the aim of supporting military navigation and fulfilling the need for quick and accurate positioning in the shortest possible time. Vast military needs led to continuous follow-up of spatial systems’ situation. ...  Read More Positioning based on satellite systems began in early 1961. GPS was evolved over time with the aim of supporting military navigation and fulfilling the need for quick and accurate positioning in the shortest possible time. Vast military needs led to continuous follow-up of spatial systems’ situation. One of the early and successful systems was the Transit Satellite. The Doppler system is formed by six satellites. These satellites revolve on polar paths around the earth at an elevation of about 1000 km from its surface. The Loran, Decca and Sat-Nav systems are among the positioning systems in operation before GPS which provided relatively high efficiency in air and marine navigation and control. GPS is a complete system. Its initial plan was designed as two projects in the U.S. Air and Marine Forces in 1960, and its major activities began in 1973 by the Ministry of Defense, which was met with rapid success. Since 1983, this technology was introduced into non-military applications such as geodetic networks, aerial navigation, photogrammetry with least ground control points, cadaster, changes in shape of the earth’s crust, marine navigation, direction of urban transportation systems, control of robots, etc.GPS is formed by three parts: Space part (satellite); system control stations; ground receiver (users).

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Aerial Photography Cameras

Mahdi Modiri

Volume 9, Issue 36 , February 2000, , Pages 2-8

Abstract

  Aerial photography can be carried out by any type of camera. Many of the utilized aerial photos are taken from a lightweight aircraft by thirty-five-mm cameras. Simplicity and low cost of taking photographs by thirty-five-mm cameras, especially for analyzing small areas, has made them an ideal sensor ...  Read More Aerial photography can be carried out by any type of camera. Many of the utilized aerial photos are taken from a lightweight aircraft by thirty-five-mm cameras. Simplicity and low cost of taking photographs by thirty-five-mm cameras, especially for analyzing small areas, has made them an ideal sensor (the actual size of the images taken by this system is 36 * 24 mm2). In some cases, seventy-millimeter cameras are also used (the actual size of images by such systems is 55 * 55mm2). On the whole, in most cases of aerial photography a camera is used that has a suitable precision. These cameras are designed to allow for taking a large number of photos in rapid succession with geometric homogeneity. Currently more than one hundred different types of cameras are used that can be categorized into one of four main categories:1- Single-frame cameras2 – Cameras with multi-lens frames3. Strip cameras4 - Panoramic cameras

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Transformation of Photography and Aerial Navigation Systems

Mahdi Modiri

Volume 8, Issue 30 , August 1999, , Pages 2-4

Abstract

  Aerial photography is one of the best methods of collecting geographic information which, considering its various applications, has been one of the most suitable tools for the valuable science of surveying over the past century. After the end of the World War II, aerial photography experienced remarkable ...  Read More Aerial photography is one of the best methods of collecting geographic information which, considering its various applications, has been one of the most suitable tools for the valuable science of surveying over the past century. After the end of the World War II, aerial photography experienced remarkable progress, and preparation of aerial photos of areas in a short period of time became possible. In 1918, in a period of four days of war, 56,000 aerial photos were prepared. In the period between two World Wars, application of aerial photos was significantly slowed down. In armed forces, interpretation of aerial photos was in direct connection with precision of photography as well as exact geometric conditions and their up-to-date information. Later, valuable progress was made in commercial and scientific branches of aerial photo preparation, and military surveying organizations practiced aerial photography, interpretation of aerial photos and conversion of photos into maps. Utilization of aerial photos for accurate measurements in photogrammetry become common. The ground-based technique of topographic map preparation was reduced in necessity and provision of maps from areas difficult to pass became possible. Germany, familiar with the importance of aerial photos and their interpretation during the Second World War, based its plans on utilization of coverage photos of forest regions. Interpretation of aerial photos was applied in estimation of the depth of waters. After the Second World War, the experiences obtained during the war regarding interpretation of photos became a basis for varied applications of it in reconstruction and peaceful developmental activities, including preparation of topographic coverage maps and developmental and cadaster large-scale maps.

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Generalizing Geographical Data

Mahdi Modiri

Volume 8, Issue 29 , May 1999, , Pages 2-5

Abstract

  Currently, Geographic Information Systems (GIS) are useful software packages in which many tools and models are as strange for users as a factory of robot assembly for a simple worker (Barrow, 1991). Unfamiliar terms limit GIS application and make users unaware of the fact that a set of data is the product ...  Read More Currently, Geographic Information Systems (GIS) are useful software packages in which many tools and models are as strange for users as a factory of robot assembly for a simple worker (Barrow, 1991). Unfamiliar terms limit GIS application and make users unaware of the fact that a set of data is the product of a long-term process that significantly limits data usability. There are methods for description of spatial data which are informally common. Today in many countries the process of preparation of basic (benchmark) coverage maps has replaced new automatic methods. But in many mapping machines the preparation of maps is still in the form of production and storage of copies of maps on various scales. There are different reasons for this fact, including: Tools necessary for production and implementation of different stages of generalization of geographic data are not available; Suitable system for multiplication and spread of new information resulted from a series of data is not possible to provide; The process of correction of vast data needs great amount of time. (Muller et al., 1995)

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Quality in Geographic Information System

Mahdi Modiri

Volume 8, Issue 32 , February 1999, , Pages 2-3

Abstract

  The basis of decision-making and selection of Geographic Information Systems (GIS) is the quality of geographic information. Many executive centers of geographic information systems and their users usually seek application and utilization of more powerful computers with various abilities such as high ...  Read More The basis of decision-making and selection of Geographic Information Systems (GIS) is the quality of geographic information. Many executive centers of geographic information systems and their users usually seek application and utilization of more powerful computers with various abilities such as high volume of memory, power of processing and graphic display (size, color and form of display) as well as a variety of programs capable of analysis and modeling, and concern less about the quality of information. It is so while today many of GIS managers’ expectations have not yet been fulfilled and many promises have failed despite vast investments in provision of hardware systems and collection, provision and storage of geographic data.Quality of information is one of the most important issues that has received less attention. Quality of information is in direct connection with precision, clarity, scientific bases of combination of information, analysis and modeling.In general, effective and determining factors can be categorized into four branches: geographic information database; structure of information; storage, search for data, distribution and propagation of information; and cartographic process of information and its necessary considerations.

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Cartographic Modeling - Part I

Mahdi Modiri

Volume 7, Issue 27 , November 1998, , Pages 2-11

Abstract

  Cartographic modeling is the general and customary method of geographical data analysis. What is used in cartographic modeling leads finally to certain algebraic relationships in which each one of effective factors in thematic combination of maps acts as a variable, and it is possible to change these ...  Read More Cartographic modeling is the general and customary method of geographical data analysis. What is used in cartographic modeling leads finally to certain algebraic relationships in which each one of effective factors in thematic combination of maps acts as a variable, and it is possible to change these variables using functions and cartographic combination in a flexible manner. In this paper, the rules, ability and major techniques of this methodology are briefly examined.

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Image Digital Processing

Mahdi Modiri

Volume 7, Issue 26 , August 1998, , Pages 2-6

Abstract

  Most of satellite images are received in digital form and the logical way of dealing with them is digital processing. Human interprets images very well. However, our eyes have limitations in observing black-and-white pictures in a range of electromagnetic waves’ spectra through looking at colored ...  Read More Most of satellite images are received in digital form and the logical way of dealing with them is digital processing. Human interprets images very well. However, our eyes have limitations in observing black-and-white pictures in a range of electromagnetic waves’ spectra through looking at colored images and a combination of different bands. It is possible that at one time they look at a particular part of three bands in a colored combination, so other bands are not used. eye is not able to fully distinguish different infrared reflections of a picture from that of another picture, while near infrared, in comparison with red waves reflection, provides useful information about various features and phenomena, especially plants. Techniques we deal with are implemented through digital analysis of images. it does not mean that visual interpretation of satellite images is not useful, but it can be highly valuable, and information can be extracted through common visual interpretation methods such as color, tone, size, shape, figure and texture of image.

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Information Output Systems in Automatic Cartography

Mahdi Modiri

Volume 7, Issue 25 , May 1998, , Pages 2-8

Abstract

  In automatic cartography, information output systems constitute a very important part. Information technology and output methods always go through their evolution according to mapping goals, and the role of information output is such that contrary to classic cartography, it is not the end of mapping ...  Read More In automatic cartography, information output systems constitute a very important part. Information technology and output methods always go through their evolution according to mapping goals, and the role of information output is such that contrary to classic cartography, it is not the end of mapping process, but a beginning to a variety of applications of digital maps and an emphasis on the scientific-engineering role of surveying and cartography engineers at stages of map utilization (design, implementation, supervision and control of projects).

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The "Sepehr" Thematic Index

Mahdi Modiri

Volume 7, Issue 25 , May 1998, , Pages 42-49

Abstract

  Here, in order to facilitate the reader’s study of the journal, a thematic index of papers published in this journal has been prepared and provided here according to ten subjects (general, natural geography, human and economic geography, urban and rural studies, cartography, terrestrial surveying ...  Read More Here, in order to facilitate the reader’s study of the journal, a thematic index of papers published in this journal has been prepared and provided here according to ten subjects (general, natural geography, human and economic geography, urban and rural studies, cartography, terrestrial surveying and geodesy, aerial photography and photogrammetry, remote sensing and satellite information, geographic information systems (GIS) and Earth in space), and the title, author or translator, issue and page of each paper have been introduced in order to ease researchers’ access to papers relevant to their interests.

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Cartographic Modeling - Part II

Mahdi Modiri

Volume 7, Issue 28 , February 1998, , Pages 2-5

Abstract

  Among various complex modeling techniques that can be used in research, there is great difference between techniques considering “what is there?” or “what can be there?” and those dealing with “what should be there?”. This difference can be expressed through descriptive ...  Read More Among various complex modeling techniques that can be used in research, there is great difference between techniques considering “what is there?” or “what can be there?” and those dealing with “what should be there?”. This difference can be expressed through descriptive and prescriptive models. Descriptive modeling techniques aim at clarification and description, and it is possible to make distinctions between techniques which analyze cartographic data and those which combine such data. Techniques aiming at analyzing cartographic data decompose data into conceptually clearer levels, while techniques combining data attempt to combine them for utilization in a particular texture. Analytical techniques of cartographic data usually deal with characteristics concerning position or form, and in the hill model (example mentioned in the main text) both can be observed. In Travel Time Layer in fig.6, the positional characteristic of each point relative to a hill is determined in terms of minutes.    

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Creation of Database

Mahdi Modiri

Volume 6, Issue 23 , November 1997, , Pages 2-5

Abstract

  In order to process cartographic information, it is necessary to determine the topological structure of data so that database becomes intelligent and ready for analysis and transfer. After collection of various data, a database with consistent topological and geometric structure should be created. This ...  Read More In order to process cartographic information, it is necessary to determine the topological structure of data so that database becomes intelligent and ready for analysis and transfer. After collection of various data, a database with consistent topological and geometric structure should be created. This task begins with conversion of all types of data and their matching on a single scale and selection of a single image or network coordinate system. But in raster computer maps and GIS there is need for something else. All pixels must be of same shape and size.

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An Article on the Principles of Remote Sensing: Application of Remote Sensing in Urban Engineering- Par III

Mahdi Modiri

Volume 6, Issue 23 , November 1997, , Pages 24-31

Abstract

  Provision of any plan for redevelopment, improvement and expansion in natural environment requires preparations in order to determine the potentials and constraints of the area. Next, after considering and evaluating development models which have been prepared in compatibility with natural factors and ...  Read More Provision of any plan for redevelopment, improvement and expansion in natural environment requires preparations in order to determine the potentials and constraints of the area. Next, after considering and evaluating development models which have been prepared in compatibility with natural factors and activities, the proper model is selected with all cultural, social, economic and environmental aspects taken into account. Provision of maps based on each effective factor and comparing them with cultural, social and economic considerations make the conditions for scientific deduction possible. By comparing environmental maps, identification of natural potential is carried out and environmental design takes place according to a precise and proper knowledge of the area.

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Statistical Analysis and Modeling

Mahdi Modiri

Volume 6, Issue 22 , August 1997, , Pages 2-3

Abstract

  Statistical analysis is an important tool for environmental planning, control and assessment. Most geographic information systems determine basic descriptive statistical indexes such as mode, mean, average, minimum/maximum and quantitative data of standard deviation, and describe characteristics that ...  Read More Statistical analysis is an important tool for environmental planning, control and assessment. Most geographic information systems determine basic descriptive statistical indexes such as mode, mean, average, minimum/maximum and quantitative data of standard deviation, and describe characteristics that occur in a certain area, including determination of the average elevation in the area within a radius of five kilometers around a point or provision of diagrams of frequency which show the distribution of values from least to most within an area. Simple statistical comparison of two or more data layers such as cross tabulation can usually be carried out within the framework of database management system created in GIS, and complex methods such as multi-regression and analysis of variance can usually be implemented by transferring data files from GIS to a general or special statistical analysis software package which has a range of progressive analysis methods, and then transfer the results back to GIS. GIS modeling is related to application of more complex mathematical methods for prediction of numerical values of environmental phenomena such as solar radiation or soil degradation at a particular point in the studied area. Models are based on simple linear equations which can be considered as a series of mathematical operations within the framework of GIS. Most of progressive models, including those based on solution of differential equations with several repetitions to reach the desirable solution, need a connection between GIS data and a suitable modeling program. The results are usually received in the form of new data layers that can be used in future analyses. These types of file transfer are necessary in any kind of analysis, because it is not reasonable to expect a geographic information system to have all modeling methods.

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A Brief Discussion on the Principles of Remote Sensing in Municipal Engineering (2) - Part VII

Mahdi Modiri

Volume 6, Issue 22 , August 1997, , Pages 4-6

Abstract

  Remote sensing is a science that provides valuable information on objects and land features by measuring distances from afar and without physical contact. In remote sensing, information can be obtained by measuring and recording the reflections of electromagnetic waves of atmosphere and ground level, ...  Read More Remote sensing is a science that provides valuable information on objects and land features by measuring distances from afar and without physical contact. In remote sensing, information can be obtained by measuring and recording the reflections of electromagnetic waves of atmosphere and ground level, which are received by sensors installed on satellites, and after their analysis, the necessary information is extracted. There are three major factors of reflection, absorption and passage in the collision of electromagnetic waves with any phenomenon, each of which depends on the wavelength of radiated energy and physical and chemical properties of the phenomenon, and the energy reflection from any phenomenon on the Earth is a function of wavelength, molecular and intracellular properties of the phenomenon and other physical characteristics of the objects under measurement. The satellite data originally contains various geometric and radiometric errors that are affected by satellite, sensor and atmospheric conditions, as well as errors in recording, transmission of information and other related issues. Satellite data become valuable and useful after making geometric and radiometric corrections. By performing geometric corrections, satellite information is readily to for analysis and utilization.

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Note

Mahdi Modiri

Volume 6, Issue 21 , May 1997, , Pages 2-3

Abstract

  Among advanced inventions and techniques, preparation and production of maps has undergone wonderful changes and transformations more than any other field. Computer progress and development of maps has reached a level that currently microcomputer programs have made users able to design and make a variety ...  Read More Among advanced inventions and techniques, preparation and production of maps has undergone wonderful changes and transformations more than any other field. Computer progress and development of maps has reached a level that currently microcomputer programs have made users able to design and make a variety of maps through interconnections. Current programs of mapping are in alignment with hardware systems of general cartographic design and drawing; they produce different files of map and move the laser imaging devices to deliver positive and negative lithographic films for making gravure. In this regard, the computer technology has transformed reading and analysis of maps. Electronic display of virtual maps (without any “real” activity) allows users to utilize powerful systems of cartographic display such as electronic atlases for quick exploration and comparison of statistical data or preparation of value maps.

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