Ali Jozaghi; Abolfazl Shamsai
Abstract
Abstract
According to recent studies, in 2025, water shortages will increase in poor countries with limited resources and rapid growing populations; hence, a long term planning is necessary for saving water resources. One of the most important plans is building a dam onperennial rivers and the main ...
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Abstract
According to recent studies, in 2025, water shortages will increase in poor countries with limited resources and rapid growing populations; hence, a long term planning is necessary for saving water resources. One of the most important plans is building a dam onperennial rivers and the main step in this process is selecting the best place in watershed. The aim of this study is to develop the multi-criteria decision support framework for dam site selection in South of Sistanand Balouchestan province. A study has been made by applying GIS and Technique for Order Preference by Similarity to Ideal Solution, to select and prioritize potential places for constructing a dam. The criteria for dam site selection have been chosen upon scholars’ ideas and available data. They include Geology, Land use, Sediment, Water Quality, Erosion, Groundwater and Hydrology. Ratio Estimation Procedure has been used to estimate weight of criteria. First, TOPSIS method and GIS have been conflated and a geospatial layer has been createdthat is called “the relative closeness to the ideal solution” whose values are between zero and one. Second, A Model has been created based on streams and topographical conditions. This model evaluates structural height, crest length of dam, and volume of reservoirs. Then, upon the results of the model, 15 places have been selected. Finally, the sites have been prioritized by finding their values on the created layer. In conclusion, the best place is A - Kahir dam- whose value is 0.85, and the worst site is P,whose value is 0.47 as well as Pishin dam which is the worst dam amongst all the dams which have been built in the region with the value of 0.62. Also, the best option is K, that is located on the right side branch of Sarbaz Riverand its value is 0.67.
Mohammad Hasan Yazdani; Afshar saidain
Abstract
Abstract
Regarding the geopolitical and strategic position of Iran in the Middle East region and the continuing threats of neighboring and non-neighboring countries, unfortunately, economic and infrastructure installations and projects have been established in the cities without security and defense ...
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Abstract
Regarding the geopolitical and strategic position of Iran in the Middle East region and the continuing threats of neighboring and non-neighboring countries, unfortunately, economic and infrastructure installations and projects have been established in the cities without security and defense considerations which have become an accessible threat to the enemy and any aggression available. Therefore, the present study was conducted to investigate the vulnerability of cities from the passive defense perspective with the case of Ardabil city. This research is an applied- developmental research in terms of goal, and a descriptive- analytical one in terms of nature.Within the framework of the passive defense issues, 18 indicators were provided in the form of five components of critical arteries, crisis management centers, military and police centers, urban equipment and support centers with three strategic, mental and support destruction priorities. The collected data were weighted in ‘SuperDecision’ software (network analysis), then mapped in the GIS environment. The results of the surveys show that, in the situation of crisis and vulnerability, there are six major hazardous areas at Ardabil level, the most important of which: the northeastern exit of Ardabil (Jihad Square leading to the gate of Astara), Southwest of Ardabil (From Sar-ein Station leading to Basij Square and towards Shamasbi Village) and eventually parts of the North and northwest of Ardabil (Vahdat Square) with the sum of 17% of the total areas of land uses in the city, have the highest vulnerability. This is due to the inappropriate situation of physical characteristics and the concentration of administrative, organizational, military and provincial institutions in these areas of Ardabil.
Mahtab Safari Shad; Mahmoud Habibnejad Roshan; Alireza Ildoromi
Abstract
Abstract The issue of drought is very important in water resources studies. Meteorological drought indices are calculated directly from meteorological data such as rainfall, and in the absence of such data, they will not be useful in monitoring drought. Therefore, remote sensing techniques can be considered ...
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Abstract The issue of drought is very important in water resources studies. Meteorological drought indices are calculated directly from meteorological data such as rainfall, and in the absence of such data, they will not be useful in monitoring drought. Therefore, remote sensing techniques can be considered as a useful tool in monitoring drought. In this research, using MODIS remote sensing satellite images, the trend of vegetation normalized index changes in Isfahan province for the years 2000-2008 was investigated. In addition to vegetation, NDVI index can be effective in addition to natural vegetation for drought monitoring, especially for drought monitoring of dry farming type.Considering this index, the vegetation cover was classified into 4 groups and the area of each of the classes was calculated. Finally, two SPI and NDVI indices were compared. The result of calculating the SPI index show that the occurrence of severe drought is in 2008 and moderate droughts are in 2000 and 2001 in Isfahan province respectively. The calculation of the NDVI index in these three years also indicated that the poor vegetation cover has been significantly increased. High level Pearson correlation (+0.704) was observed between SPI and NDVI in significant level of 0.01. However, the results of the effect of rainfall on the NDVI index showed that there is no coincidence of the occurrence of meteorological drought and agriculture droughts in all years. For the year 2006, despite the fact that precipitation was higher than the years before and the years after and more than the average rainfall of the province, but based on the results of the NDVI index, agricultural drought has occurred this year (Devaluation of the NDVI index). On the contrary, in 2002 and 2004 that precipitation was lower than 2006, but dry farming and pasture conditions were better than 2006. And also, in 2003 with a difference of 2 mm in precipitation compared to 2002, the NDVI index value dropped significantly. The results of this research double the necessity of defining a profile that expresses all of these issues.
Mostafa Kheyrollahi; saeed nadi; Najmeh Neisany Samany
Abstract
Abstract
Due to the sensitivity oftheir missions, urban emergency vehicles are alwayslooking forthe shortest timeto reach the destination. In big cities, in addition todistance, several factors and parameters with respect to the complexityand extent of thetransport and traffic, are influencing time ...
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Abstract
Due to the sensitivity oftheir missions, urban emergency vehicles are alwayslooking forthe shortest timeto reach the destination. In big cities, in addition todistance, several factors and parameters with respect to the complexityand extent of thetransport and traffic, are influencing time of arrival of an emergency vehicle, some of which are qualitative or quantitative, dynamic or static. In this paper, the modern approach used, is based on composing conflation models, Gamma quantification methods, travel time prediction formulas and meta-heuristic algorithms in order to find most optimal route. In this paper, first we have tried to introduce all the calculated, available, qualitative and quantitative, affecting factors related to emergency routing, thenwith converting qualitative parameters to quantitative ones, we normalize each parameter by the maximum approach and conflate them in such a way that thepriority and impact of each parameteris determined to find the optimal route. In order to calculate the priority and impact of factors, the Gamma test method, as a data derived method is selected. The procedure is implemented by the use of road network and traffic volume data from two regions of Tehran. Based on this approach, the considered weights for each following criterion of degree of difficulty including quality, width, slope, category, and route directness are 0.331, 0.286, 0.188, 0.172 and 0.020, respectively. Finally, genetic meta-heuristic algorithm is used to select the optimal route and the results compared with common Dijkstra routing algorithm. The length of the selected route by GA is about 130 meters in one time and about 300 meter in the other time more than the selected one by Dijkstra algorithm. Based on the implemented comparison, the represented approach in this paper had a considerable superiority over the simple current methods.
Mahboobeh mohammad Yusefi Bohluli Ahmadi; Abdolreza Safari; َAnahita Shahbazi
Abstract
Abstract
Global gravity field is commonlymodelled in spherical harmonic basis functions to a certain degreeof spectral and spatial resolution. Non-uniformdistribution and different quality data limitthese functions in local gravity field modeling.Spherical harmonic basis functionsshow more global properties ...
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Abstract
Global gravity field is commonlymodelled in spherical harmonic basis functions to a certain degreeof spectral and spatial resolution. Non-uniformdistribution and different quality data limitthese functions in local gravity field modeling.Spherical harmonic basis functionsshow more global properties that means they are suitable forshowing low frequency gravityfield. In local-scale studies, radial basis functionson the sphere with quasi-local support can improve gravityfields up to a high spatial/spectral resolution.The local modelsare usually moreaccurate than global modelsin the desired locations.These functions are usually notorthogonal on a sphere, which makes the modelling process morecomplex.In this study we evaluated the radial basis functions: point-mass kernel, radial multipoles, Poisson and Poisson wavelet ,and then we compared their performances in regional gravity fieldmodelling on the sphere using real gravity acceleration data in Farscoastal area. A least-squares technique has been used toestimate the gravity field parameters. Iterative Levenberg-Marquardtalgorithm is appliedfor nonlinear inverse problem solving and minimization of differences between calculated andobserved values. These parameters include number, location, depth and scalingcoefficients in radial basis function.In order to increase efficiency Levenberg-Marquardt algorithm for solving gravity field modeling, the initial valueof theregularization parameter determined with a relation based on objective functionJacobian and also a method is provided for this parameter updates. Theresults showed that the accuracy of gravity field modeling forany types of radial basis function would be almost thesame, if the depths of SRBFs are chosen properly.
shahabadin isalou; Gholamreza Latifi; VAHID GOODARZY
Abstract
Abstract
Confronting natural disasters and managing that by using the most efficient means, have always been subjected to deliberation, investigation and examination from various aspects. But, a comprehensive and locative analysis on the spur of the moment is always an essential act that must be taken.In ...
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Abstract
Confronting natural disasters and managing that by using the most efficient means, have always been subjected to deliberation, investigation and examination from various aspects. But, a comprehensive and locative analysis on the spur of the moment is always an essential act that must be taken.In this field, geographic information system is capable through integrating information of providing a comprehensive analysis and identification of the zones which require attention and have been very effective. Among natural disasters, earthquake is very unpleasant and leaves the highest mortality rates, hence, its management is very important, especially in the urban context. Most injuries from the earthquake due to the physical resistance of tissue, the impossibility of relief and incapability of reversibility had been in direct or indirect connection with undesired structural situations. This paper tries to offer the most effective strategies to achieve a higher quality of physical safety against potential earthquakes through assessment of physical vulnerability and determine vulnerable zones.
Materials & Methods:
Using the five indicators, (population density, land use risks, quality of buildings, age of buildings, access to the centers of relief and rescue) information layers of each of these variables were produced and these layers were integrated using the Analytic Hierarchy Process IHWP in Arc GIS environment, and the location of district 1 was evaluated against earthquakes.
Results & Discussion:
Findings show that the physical texture of district 1 in Tehran is relatively safe against possible earthquakes, districts 9, 7 and 5 are very safe,districts 4, 6 and 10 are safe, and districts 2 and 8 are moderately safe. Districts 1 and 3 were assessed as areas with low safetyand subjected to disaster. In general, the north of this area has narrow passageways and streets, high-rise buildings, worn out textureand ruined sites, which is unsafe and vulnerable to earthquakes.
Conclusion:
Based on the principles of urban management,non-standard sales of building density by the municipality of Tehran in this area and the growing trend of population is considered to be the main problem and a serious threatening alarm to the life of the region.
Zohreh Maryanaji; Hamed Abbasi
Abstract
Abstract
Two important characteristics of Hamedan climate are irregular precipitation time and maximum 24-hour precipitation in the months of March (20th) and April (20th). This factor, namely severe rainfall, has increased the risk of flood in this province. The precipitation is snowy in the winter ...
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Abstract
Two important characteristics of Hamedan climate are irregular precipitation time and maximum 24-hour precipitation in the months of March (20th) and April (20th). This factor, namely severe rainfall, has increased the risk of flood in this province. The precipitation is snowy in the winter season, and the melting time accompanied by the rain, causes rivers to flood. The land’s lack of the crop and vegetation cover in other months of the year and the dryness of the soil and ..., increase the flood. Flooding factors are diverse in Hamadan province. Some of the most important factors influencing the flooding of an area are climate, inequalities of vegetation, etc. In this paper, maximum daily rainfall has been investigated in order to predict the amount of water that can be extracted from floods and to plan for management of the region’s water resources. For this purpose, on the basis of maximum 24-hour precipitation, the map of the elevation and rainfall gradient model and the rain map of the region for the return period of 2,10,25,50 with the ‘best statistical distribution’ method for the region (Gamble distribution) are estimated and zoned in the GIS environment (by Kriging method) and the probable daily precipitation decreases by the reduction in the return period.Accordingly, during the aforementioned return periods, the southeast and northwest regions of Hamadan province (Dasht-e-KaboodarAhang) have the most probable daily precipitation.The abundance of the number of floods in the province reflects the fact that the aforementioned regions have the highest numbers and the (the most terrible floods in the province (1987 flood in KaboodarAhang region). According to these maps, the eastern parts of the province have the least probable daily precipitation. The results of this study can be used in flood zoning and forecasting as well as planning and management of water resources in the region.
Mohammad jokar; Kamran Lari
Abstract
Abstract
Tidal field data is very important in coastal engineering researches such as developing the beaches, calibration of Numerical hydrodynamic models, hydrography, sediment transport and other things.The aim of this study is to evaluate and validate numerical hydrodynamic modeling by using field ...
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Abstract
Tidal field data is very important in coastal engineering researches such as developing the beaches, calibration of Numerical hydrodynamic models, hydrography, sediment transport and other things.The aim of this study is to evaluate and validate numerical hydrodynamic modeling by using field measurements of tidal measuring stations and to find a level tidal model in the Persian Gul. Therefore, bathymetry and coastline data and one year data of ten tidal measuring stations in the Persian Gulf and the wind field GFS were used for this purpose.Tidal currents were simulated using FM[1] software MIKE21 with irregular mesh structure and considering the astronomical forces, and verified by the results of the station measurements. In the next step, the tidal components were extracted. The simulation of the Persian Gulf's tidal current with the MIKE model was very well adapted to the field data of the tide measuring stations.In the final stage, the values provided by the FES global model were extracted using Matlab software. The results of the tidal analysis derived from the global oceanic tide model were evaluated and compared with the results of the tidal analysis derived from the modeling (results from the tide measuring stations). Based on the results in the study area, the tidal components obtained from the global oceanic tide model in the coastal and shallow zones, showed a low correspondence and accuracy with the tidal components of the tide measuring stations. This is despite the fact that less difference was observed between the corresponding components in deep areas.
1- Flow Model
Saeed Balyani; mohamad salighe
Abstract
Abstract
The aim of Exploratory SpatialData Analysis (ESDA) is, distinguishing the difference between random andnon-random patterns. In this study, 37 meteorological and synopticstations in the northern region of the Persian Gulf (Mondand helle basin) were used to analyze the spatial changes of precipitation ...
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Abstract
The aim of Exploratory SpatialData Analysis (ESDA) is, distinguishing the difference between random andnon-random patterns. In this study, 37 meteorological and synopticstations in the northern region of the Persian Gulf (Mondand helle basin) were used to analyze the spatial changes of precipitation regime, monthly and quarterly. According to the drawnprofiles on monthly rainfall in different seasons along the meridiansand orbits, the precipitation raised from the west to the east of the basin. Also, along the meridians, monthly precipitation had a decreasingtrend from the north to the south of the study area. The ESDAof precipitation data in the study area showed that meancenters and standard deviational ellipse are located in the center and nearthe high rainy areas in winter and spring. But, thisbehavior was very different in summer, because mean centers andstandard deviational ellipse of precipitation tended towards the south and the southeast of the study area. The analysis of spatial autocorrelation showedthat high-high clusters of monthly precipitation in most months of the year except for two months of summer (July and August) are located inthe east and the northeast and low-low clusters are locatedin the west, south and south West of the basins.
Seyed Ali Alavi; Seyed Mostafa Hosseini; Fariba Bahrami; Mehrab Ashorlo
Abstract
Planning with the aim of crisis management and earthquake risk estimation has always been one of the main concerns of urban planners and managers. In order to plan crisis management before the occurrence of earthquake, determining the vulnerability rate of urban fabrics to earthquake is necessary. ...
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Planning with the aim of crisis management and earthquake risk estimation has always been one of the main concerns of urban planners and managers. In order to plan crisis management before the occurrence of earthquake, determining the vulnerability rate of urban fabrics to earthquake is necessary. This research was aimedat providing an appropriate model for assessing the vulnerability of urban fabrics of Semirom city,located in Isfahan province, to earthquake. The current research is descriptive-analytical in nature with practical aims. To begin with, the criteria affectingthe vulnerability of urban fabrics to earthquake were identified, and then the value and importance of each criterion was determined by using Analytic Network Process. Finally, the results obtained from Analytic Network Process, were integrated with main and side roads, population density, buildingsquality, land slope, distance from fault, green space, health centers, cultural centers, and educational and residential centers, and vulnerability map of Semirom’s urban fabrics to earthquake was prepared. The results showed that among the studied criteria, population density, side road and distance from the fault were the most important criteria, while distance from cultural and educational centers had the least importance in vulnerability of urban fabrics. Furthermore, vulnerability of the northern and central parts of the city was higher than other areas of the city due to their proximity to the fault line and the presence of old buildings in these parts. Based on the results obtained from digital layer of urban fabrics of Semirom city, losses and damages caused by the earthquake can be significantly reduced by proper planning before and after the occurrence of earthquake. It should also be noted that tectonic aspect is one of the factors that has always been neglected throughout the history; therefore paying attention to slope issue and other factors in urbanism has had evolutionary process.
Hossein Asakereh; Hasan Shadman
Abstract
Abstract
Hotdays are temperature extreme states and are considered to be one of the important climatic phenomena. Long term changes (trends) of thisphenomenon arethe consequences and evidences of thermal-climatic changes. Also, these days can affect the ecosystems and human life. Therefore, recognizing ...
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Abstract
Hotdays are temperature extreme states and are considered to be one of the important climatic phenomena. Long term changes (trends) of thisphenomenon arethe consequences and evidences of thermal-climatic changes. Also, these days can affect the ecosystems and human life. Therefore, recognizing the behavior of hot days can be the source of many topics. In this research, we tried to investigate the long-term trend of Iran's hot days using the network data of the country’s average maximum temperature from 1961 to 2007 and statistical methods. For this purpose, the hot day profile was studied based on the percentile of ninety for each pixel from the network and was estimated on each day of the year. Thus, a threshold of heat occurrence was obtained for each pixel every day. Then, the days whose temperatures equaled or exceeded this threshold, were considered hot days.The average number of hot days in the country is 39 days. The cold season months, as well as April, have the highest frequency of the average hot days.The frequency of hot days is increasing. The number of hot days has made a positive trend for about half of the country. Also, the average temperature of hot days has also been checked. The trend of the average temperature of hot daysin more than half of the countryhas been positive and in around one third of the country has been negative.The hot days’ temperature-related events of Iran have a 3 to 4 year cycle. Toanalyze the trend in data, linear regression was used with least squares error method and a spectral analysis method was used to investigate the existence of significant fluctuations in the data.
Saharnaz Shekoohizadegan; Hassan Khosravi; Hossein Azarnivand; Gholamreza Zehtabian; Behzad Raygani
Abstract
Abstract
Desertification means land degradation in arid, semi-arid and dry sub-humid regions in result of climate variability and human-activity. Desertification is the third major challenge for international community in twenty-first century after the two challenges of climate change and scarcity of ...
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Abstract
Desertification means land degradation in arid, semi-arid and dry sub-humid regions in result of climate variability and human-activity. Desertification is the third major challenge for international community in twenty-first century after the two challenges of climate change and scarcity of fresh water.This phenomenon has been raised as one of the most striking aspect of environmental degradation and destruction of natural resources in the world.Desertification, byaffecting vegetation cover, water and soil, is a serious factor threatening national parks in arid and semi-arid regions including Iran.Executive actions related to desertification control must be based on the recognition of the current state of desertification and its intensity.The aim of this study was to evaluate and monitor desertification by usingvegetation indices (NDVI and EVI) extracted from MODIS satellite imagery and classification of desertification by using fuzzy logic.
Materials and Methods
The study area covers an area with about 47,244 hectares, which has been named as Bamou National Park.The height distribution of Bamou National Park shows that most of the area is locatedbetween 1700 and 1900 meters altitude and a maximum height of the study area is 2700 meters above the sea level.The average annual rainfall in the main station area representing the Shiraz station is 392.9 mm with a mean annual temperature of 17.9°C.Based on Domarten developed method, Bamou National Park has a semi-arid climate and is cold with winter rains.
In this research, to monitor and evaluate desertification in Shiraz Bamou national park, the annual changes in vegetation cover were studied during the period of 2000 - 2014. On the other hand, this paper tries to monitor desertification changes using long term-time series analysis of satellite data and vegetationcover indices (EVI & NDVI).Therefore, in this study, profile and map of annual changes were prepared on IDRISI Selva and then analyzed using the MOD13A1product, MODIS sensor, Terra satellite and Aqua system. Finally, using fuzzy logic, profile and desertification intensity map were prepared for 2000-2014. According to the climatic conditions of the region and based on expert opinion, the value of fuzzy classes index changes, the software IDRIDIselva and Arc GIS 10.2 severity of desertification on each indicator based on fuzzy logic was prepared.
Discussion and results
Based on the results of EVI & NDVI, vegetation destruction and desertification intensity have been more in the north west of the study area. The reason for this destruction and desertification is the construction of the new city of Sadra in part of the North West and the west of this park. It can be said that, this degradation is a new form of desertification entitled anthropogenic desertification.As a result of the construction of Sadra city in the western area of the park, it is practically impossible to protect this area.The results show that EVI is more sensitive than NDVI for monitoring parameters such as canopy cover, leaf area index, canopy structure, phenology, and stress plants. The EVI index due to greater sensitivity to changes in areas with high biomass (vegetation growth season) and mitigating the effects of atmospheric conditions on vegetation index values is more applicable to monitor vegetation changes than NDVI.This paper introduces fuzzy logicas one of the methods for classifying the severity of desertification. Fuzzy logic can be used to determine the boundaries of class and privilege of desertification indicators and explain the process. Fuzzy sets, or classes of fuzzy are no sharply defined boundaries and membership or non- membership of a place in particular.The severity of desertification in the form of fuzzy maps based on each available indicator provided the values between 0 and 1 as the classes of desertificationon the map.It can be concluded that for better management of desertification it is necessary to prioritize areas affected by desertification according to its severity.As a result, we can say that accurate desertification classification can be helped to manage this phenomenon. In fact, it is a set of unpleasant consequences that human environment brings. Hence, monitoring and evaluation of the severity of desertification and mapping always isone of the most important management andplanning tools to achieve sustainable development in the field of natural resources.
