Zahra Bahari Sojahrood; Reza Aghataher; Mohsen Jafari
Abstract
Extended Abstract Introduction Earth roughness represents a fluctuation of the earth’s surface, and it can be called the complexity of the earth (Wilson, 2012). Roughness calculation is of great importance and is the basis for lots of decision-making. There are various solutions for the roughness ...
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Extended Abstract Introduction Earth roughness represents a fluctuation of the earth’s surface, and it can be called the complexity of the earth (Wilson, 2012). Roughness calculation is of great importance and is the basis for lots of decision-making. There are various solutions for the roughness calculation. The first description of roughness was presented by Kupers, in which the roughness surface is assumed to be a set of points (Kupers, 1957). According to this definition, the deviation from the height criterion of the points is considered as the roughness index. The calculation of roughness in vast areas is possible only through satellite interpretation. The images used for this purpose should be of considerable power (Ghafouri, 1394). The main purpose of this paper is to automatically determine the parts of the area using the digital elevation model (DEM), which are desirable for the user in terms of roughness. To achieve this goal, a local decision-making support system is needed. In most of the mentioned methods, roughness is calculated as a variable in a region. But, the purpose of the paper is to calculate the roughness in different parts and to select the optimal area of the user. In previous methods, in order to achieve the goal, the roughness variable had to be calculated in each range and these ranges had to be compared one by one. This process is time-consuming and sometimes the desirable accuracy is not obtained. Therefore, there is a need for a method that reduces the time and increases the accuracy. For other purposes of this paper, we can refer to the calculation of roughness on a surface. In this research, a new method was developed for determining the areas with the user’s desirable quality of roughness using a DEM and based on the fractal method and spatial decision-making support system and a system with robust tools was designed and implemented for estimating the roughness and it was tested by the digital elevation model of Iran. The results indicate that this method is very accurate. Materials & Methods Ground roughness is an important variable used in the sciences of the earth and astronomy. There is no unique definition for it. It can be defined as a variable to express the variability of the Earth’s surface on a certain scale. In this research, to determine the favorable areas of the user in terms of roughness, a number of methods including sigma T, sigma Z, fractal geometry and a developed method of fractal geometry were used to calculate the roughness. Various spatial analyses were also used in the system. Finally, the spatial decision-making support system was developed for ranking and selecting the patches. Results & Discussion The system was implemented in the ‘Visual Studio’ environment using the ‘C #’ language and the ‘arcengine’ library. This system consists of several parts. First part, is the determination of the area whose roughness is to be determined. The second part, is the extraction of the patches of that area, the third part, which is done after the extraction of spatial complications and descriptive information of each patch, is similar to a filter which is based on roughness calculation methods. The four parts is, the ranking of these patches, and the fifth part, is their classification. The system is designed in such a way that the digital elevation model of any areas with any accuracy can be used. In this research, a 90 meter digital elevation model of Iran and the raster layer of its slope (produced in ArcGIS environment) were used. To display, Google maps were used. This method has a high precision due to its pixel-to-pixel scanning capability of the area and it seems to be more accurate than the existing ones. In most roughness determination methods, there is a method that calculates the roughness in the determined area. But, in this paper, using a spatial decision-making system and using the division of the region into smaller regions, the desired qualitative areas of the user are determined in terms of roughness, therefore, this method is able to decide automatically with regard to the user’s needs. Quality is different for various applications in terms of roughness. Sometimes high roughness and sometimes low roughness is favorable. However, other methods only calculate an amount of roughness of a region and we have to extract the values for each part of the earth and apply the analysis to it, and then compare them to determine their desirability. Several methods of calculating the roughness can also be used in the system simultaneously. Conclusion Earth roughness is a term used to describe the irregularities of an area. In most cases, determining the roughness of the earth is very complicated. There are many methods for calculating the roughness. The proposed method in this project is an innovative idea which is based on spatial analysis, spatial decision-making support system and roughness calculation methods and is calculated using the Digital Elevation Model. The results show that this method is a powerful tool for calculating roughness. In order to improve and continue this work, the correlation of variables is suggested in the calculation and evaluation of the obtained results. In this paper, the values are also calculated at the surface of each patch and in rows regardless of the direction. Various models can be used to consider the order of cells in each patch and compare the results.
Reza Aghataher; Mohammad Fallah Zezoli; Mehrdad Zarafshar; Mohsen Jafari
Abstract
The present research was conducted with the aim of locating the susceptible military centers and determining the favorable areas for its construction in a part of dense forests in Golestan province-Ali Abad Katoulcity, using the Analytical Hierarchy Process (AHP) and Geographic Information System (GIS). ...
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The present research was conducted with the aim of locating the susceptible military centers and determining the favorable areas for its construction in a part of dense forests in Golestan province-Ali Abad Katoulcity, using the Analytical Hierarchy Process (AHP) and Geographic Information System (GIS). For this purpose, using defense experts’ opinions, university professors, military experts and resources review, information layers, slope percentage, slope direction, elevation classes, distance from the canal network, distance from the road, distance from villages, lithology, density of vegetation and distance from urban areas as factors affecting the location of susceptible military centers in forest areas were identified and the aforementioned maps were prepared and digitized in the GIS environment.In the next step, standard AHP forms were prepared and assigned to different experts in order to weight and prioritize effective factors. Weighted forms were collected and each of them was analyzed separately in Expert Choice software and AHP module in Arc GIS 9.3 software. Finally, the weight of each of the criteria and sub-criteria related to the target was determined. The results of the evaluation showed that the three factors of distance from the city (0.321), distance from the road (0.217) and lithology (0.176) have had the most impacts on the location of the susceptible defense centers of the study area, while the density of the vegetation (0.023) and direction of slope (0.017) have had the least effects. Eventually, the final potential map of the susceptible defense centers was prepared using the AHP model in the GIS software environment, and was divided into four subcategories of low potential (9.07%), medium (41.8%), high (30.01%) and very high (19.13%).
Reza Aghataher; Soroush OjGH; Mohammad Fallah Zazuly; Mohsen Jafari
Abstract
Today the desire to create smart and electronic companions in the daily life of humans has been fulfilled with the production of mobile processing equipment. On the other hand, the integration of existing capabilities of these equipment with the features of the spatial information systems, has become ...
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Today the desire to create smart and electronic companions in the daily life of humans has been fulfilled with the production of mobile processing equipment. On the other hand, the integration of existing capabilities of these equipment with the features of the spatial information systems, has become the basis for the emergence of a new technology called spatial information system. Simply put, displaying the spatial information can be considered as the most vital part of a mobile spatial information system. On the other hand, allocating a major part of the commercial market of mobile equipment to devices running with Android operating system encouraged the authors to explore different visual techniques in such equipment. The analysis can be considered as one of the most important studies required to develop a sample of a mobile spatial information system. But unfortunately, despite the great importance of this issue, no comprehensive and technical studies have yet been conducted to evaluate the performance of different methods of displaying spatial information in the context of this operating system. The methods used in this study include the use of Google Map API, ArcGIS Runtime SDK, OSMDroid, MapsFroge and Nutiteq libraries. To compare these methods and express the use cases of each of them, services were developed using each one of these methods and the Java programming language. Finally, after analyzing the results of various experimental experiments, the quality of performance, capabilities, strengths and weaknesses of each method were clearly expressed. In general, the results of this study can be considered as an appropriate starting point for selecting an appropriate library for displaying spatial information in any instance of a mobile spatial information system.
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.
