Hamid Enayati; Mohsen Hasanzadeh Shahraji
Volume 22, Issue 87 , November 2013, , Pages 48-53
Abstract
Availability of spatial information and decision making based on the analyses performed by geographic information system are among the fundamental components of sustainable development. For this purpose, an organization or more is responsible for the production of spatial information in different countries. ...
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Availability of spatial information and decision making based on the analyses performed by geographic information system are among the fundamental components of sustainable development. For this purpose, an organization or more is responsible for the production of spatial information in different countries. In recent years and in the era of information technology and public access to internet, creating a platform for providing spatial information in cyberspace is considered to be much more important. As a result, the new generation of spatial information products have the capability of being presented and disseminated in the cyberspace. Some organization have proceeded and not only pioneered for dissemination of spatial information in the Internet, but also have provided users with the possibility of performing some basic spatial analyses. In developed countries, these possibilities are available and spatial information is being provided in cyberspace. In order to take advantage of developed countries knowledge and experience in producing and disseminating spatial information, it is necessary to evaluate the procedure of producing spatial data in these countries. USGS in United States of America and Survey Ordnance in UK are responsible for producing spatial data. Therefore, the present article investigates the procedure of producing spatial information.
Mohsen Hassanzade Shahraji; Ali Mohammadzadeh; Kurosh Khoshelham
Volume 20, Issue 80 , February 2012, , Pages 34-39
Abstract
In recent years, a new sensor called Lidar Continuous Wave has been introduced into the commercial laser scanners family. The main advantage of this new type of sensors is the complete recording of the return pulse after the collision with various ground features along the path of the laser pulse to ...
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In recent years, a new sensor called Lidar Continuous Wave has been introduced into the commercial laser scanners family. The main advantage of this new type of sensors is the complete recording of the return pulse after the collision with various ground features along the path of the laser pulse to the surface of the ground. With full wave recording, the output of the cloud of points has a higher density and more reliability, along with new parameters, including pulse widths and pulse amplitudes for each point. These new parameters help us analyze and investigate outcomes of the three-dimensional cloud of points of these types of sensors ever more correct and comprehensive . Lidar's output can be applied in various fields, including updating 3D databases, extracting ground features, providing a 3D model of buildings, providing forest models, urban management and planning, traffic management, air pollution control, tourism industry, crisis management, and many other applications. In this article, we first discuss some points about the Lidar Continuous Wave sensor, the signal processing carried out on it so far, and how to extract the three-dimensional points from it. Examining different types of these sensors and a brief history of their evolutionary process forms the next section. In the end, various applications of this data in forest, urban and hydrographic fields are discussed.
