Reza Aghataher; Mahdi Samadi; Ilia Laliniat; Iman Najafi
Abstract
Abstract
Digital Elevation Models (DEM) enable researchers to perform geographical researches on a global and regional scale such as global changes, natural disasters, environmental hazards, environmental monitoring, etc. Therefore, DEM data plays a key role in scientific researches. SRTM and ASTER ...
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Abstract
Digital Elevation Models (DEM) enable researchers to perform geographical researches on a global and regional scale such as global changes, natural disasters, environmental hazards, environmental monitoring, etc. Therefore, DEM data plays a key role in scientific researches. SRTM and ASTER GDEM are two elevation datasets that cover nearly the entire land surface of the earth and are globally available (for almost 80% of the earth). Thus, it is necessary to evaluate the vertical accuracy of such data prior to their use and to select the appropriate data considering the research target. ASTER-based digital elevation model has spatial resolution of 30 meters, which seems to provide more precise elevation data than SRTM with 90 meters spatial resolution. Several studies have been performed for evaluating the accuracy of each of these two datasets in various countries of the world. The results of such studies indicate their advantages and limitations over each other. In this study, the vertical accuracy of these two DEMs are evaluated by ground control point in three zones of Iran with different topographic characteristics which are East Azerbaijan, Sistan and Baluchestan and Bushehr. Results show that the RMSE of SRTM as the index of error for the study area in East Azerbaijan, Sistan and Baluchestan and Bushehr are 6.1, 7.4 and 2.9 meters and in ASTER GDEM are 8.7, 8.3 and 7.2 meters respectively. Therefore, the vertical accuracy of STRM is higher than that of ASTER GDEM in all three zones. In this research, the relation between vertical error and land characteristics including slope and direction of slope has been studied and the results have been presented. The final findings of the research indicate higher vertical accuracy for SRTM compared to ASTER GDEM in Iran and it is concluded that SRTM is a more appropriate choice for various applications.
Hasan Ali Faraji Sabokbar; Mahdi Mahdi; Reza Aghataher; Siamak Taghizadeh Ghalejuqi; Saeed Rahimi
Abstract
Disaster, crisis and then the search, rescue and reliefis a cycle frequently repeated in a country like Iran. In this cycle, commonly known as the crisis management cycle, we are constantly faced with a variety of data and outputs from the early stages, namely, determining the risk of areas to the post-crisis ...
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Disaster, crisis and then the search, rescue and reliefis a cycle frequently repeated in a country like Iran. In this cycle, commonly known as the crisis management cycle, we are constantly faced with a variety of data and outputs from the early stages, namely, determining the risk of areas to the post-crisis stages and retrieval, which are somehow related to the location. Collectinginformation both in the pre and post-crisis stages will notbe a very difficult task, as the damaged society is then almost relieved from panic and therefore resources permit the authorities in charge to gather information as requiredHowever, during the crisis andas long as the society is suffering from critical conditions, collecting information such as the depth of damages, damaged areas, risk-prone areas, dispersion of damages, resources, facilities and … will be very useful and obviously difficult. Thus, considering the lack of tools andappropriate technology in the country for gathering information during crisis conditions, this research has focused on gathering information in the crisis management response phase. In this regard, concepts of Telegeoinformatics (TGI) and its various architectures were presented and continued with designing a system for gathering information during earthquake crisis. Finally, an emergency response system was designed and was presented as a software package. Moreover, the model and software of this system was presented in UML for further development by other researchers who are studying in the same fields, which resulted in presentation of suggestions for development of this system using other technologies.
Mahdi Modiri; Reza Aghataher; Mohammad Fallah Zazuli; Mohsen Jafari
Volume 22, Issue 86 , June 2013, , Pages 5-16
Abstract
Effective planning and decision-making require access to accurate and updated information. Having updated spatial information and proper application of it is one of the most important topics in the command. A C4I system is composed of several smaller systems that can help military commanders assess the ...
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Effective planning and decision-making require access to accurate and updated information. Having updated spatial information and proper application of it is one of the most important topics in the command. A C4I system is composed of several smaller systems that can help military commanders assess the enemy’s information and make better decisions. Geospatial Information System )GIS( can assist commanders in achieving more rational decisions. GIS by modeling the Earth and the effect on Earth will provide a good view of the operating area for military commanders. This article reviews the role and application of Geospatial Information System in development of command and control.Using of new technologies such as mobile Geospatial Information System )Mobile GIS( and web-based Geospatial Information System )WEB GIS(, followed by locating the best places with different functions are GIS capabilities in command and control )C4I(.Thus, using Geospatial Information System capabilities by modeling of the operating area can be reached the highest rates in optimal and valid decisions for command and control.
Mohammad Hassan Nami; Reza Agha Taher
Volume 16, Issue 64 , February 2008, , Pages 11-18
Abstract
Management is the art of decision making. In urban environments, which are basically complex assortments of a wide range of components and interactions, managers should display their decision-making ability on a high level. The importance of this matter will be intensified when we know that urban environments ...
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Management is the art of decision making. In urban environments, which are basically complex assortments of a wide range of components and interactions, managers should display their decision-making ability on a high level. The importance of this matter will be intensified when we know that urban environments are the most vulnerable environments, particularly to natural disasters. In addition, the results of such hazards are all-encompassing and lead to human casualties and various economic and social losses. One of the most recognized threats to urban environments is the earthquake. The frequency of earthquakes and their results, especially in areas susceptible to earthquakes, has caused urban managers feel pressed by society and policy makers to adopt effective strategies to address this issue. These strategies can be observed in the area of policy-making and strategy-determination to create a good level of coordination and subsequently integration of resources for addressing the management of earthquake crisis, as well as in the use of various research and technologies concerning recognition of different aspects of the earthquake phenomenon and its effects. In this context, urban crisis management can be defined as an integrated combination of strategies, policies, research, and technology. In this regard, international efforts to develop macro strategies and to encourage communities to follow them in order to provide an adequate level of security and prosperity of urban life indicate the universal importance of urban crisis management, and in particular earthquakes. Since Iran, and especially Tehran, are always subject to earthquakes, this paper examines the activities carried out in connection with natural hazards of earthquakes, especially in urban environments around the world and Iran.