Geographic Data
Iraj Teimouri; Akbar Asghari Zamani; Erfan Moharrampour
Abstract
Extended AbstractIntroduction: UHI is a phenomenon whereby urban regions experience warmer temperatures than their rural surroundings. UHI influences well- being and welfare Average energy consumption and consequently, pollution and social equity of cities. Many factors contribute to urban heat island ...
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Extended AbstractIntroduction: UHI is a phenomenon whereby urban regions experience warmer temperatures than their rural surroundings. UHI influences well- being and welfare Average energy consumption and consequently, pollution and social equity of cities. Many factors contribute to urban heat island formation, as time (day and season), synoptic weather (wind, cloud), city form (materials, geometry, greenspace), city function (energy use, water use, pollution), city size (linked to form and function), geographic location (climate, topography, rural surrounds). Due to UHI adverse impacts on urban metabolism, ecological environment, the favourable living condition of cities and overall livability of cities, it has been an important research topic across various field of study and scholars gave more and more attention to it. UHI has been studied for a long time, it was first described by Luke Howard in the 1810s. During the last decade Significant research efforts have been performed to evaluate the urban heat island phenomenon's impact on the urban environment. According the literature review the main goal of this study is; exploring the effect of Urban Morphology on UHI, in the Tabriz city. Materials & MethodThis study is a correlation one. Be. In this research, ArcMap, ENVI and SPSS software have been used to generate data and apply relationships. To conduct this research, Landsat 8 images of OLI sensors at different dates for summer and winter have been used. In this study, to evaluate the UHI and influenced area of the city, the satellite images of land sat 8 OLI/ TIRS (thermal band 10) were used. The land sat 8 OLI/TIRS images that covered Tabriz summer and winter in the year of 2014 to 2019 were provided by USGS.To perform radiometric correction of images from ENVI 5.1 software using FLAASH method. Flash is the first atmospheric correction tool that corrects visible wavelengths and infrared and infrared wavelengths of up to 3 micrometers. In the flash method, the Meta Data file is used to correct the desired bands, which include multispectral bands and thermal bands. For multispectral bands, radiance and reflection operations were performed, but for thermal bands, only radiance operations were performed. In this context, the Lowest and Highest Position, Spatial Autocorrelation, Hot and Cold spots and finally multivariate Regression analysis were used.Results and Discussion The results of this study showed that the high temperature is most widespread in suburban areas especially in north west and south east rather than central parts of the city. According to the research findings, the average temperature of Tabriz in summer for the studied periods is equal to 37.7 ºC. also the average temperature varies in different years and does not show a specific trend. The average temperature of the city during the study period in winter is equal to 11.8 ºC. But according to the finding, the average temperature of the city in summer and winter is low compared to the surrounding areas. The average temperature difference between the city and surrounding areas is 33.7 ºC and 22.5 ºC in winter. Findings related to the autocorrelation pattern of Moran spatial analysis also show that the distribution of UHI in the city of Tabriz is clustered. The present study also showed that urban morphology can affect the intensity of Heat Islands. Based on the findings of regression analysis and calculated F (17.65) and the coefficient of significance obtaind at the level of 0.00, the predictor varizbles can well satisfy the behavior of the research dependent variable in the summer. For winter, the whole model can be generalized according to the calculated F (9.36) and significance coefficient (0.00). on the other hand, the present study showed that the distance from the green space has an effect on the intensity of UHI, so that based on the findings of the study and calculated F(7.596) and significant level(0.00) this can be confirmed.ConclusionThe present study sought to investigate the effect of urban morphology on the intensity of UHI. For this purpose, we used Landsat 8 satellite images and the technique of separate window algorithm to estimate the surface temperature. Spatial statistical analyzes such as Moran and Hot & Cold spots and multivariate linear regression were also used for analysis. In line with previous studies conducted in Iran, this study also showed that the temperature inside the city is cooler than the surrounding temperature and in a way in a city like Tabriz, we are facing cold islands instead of heat islands. The reason can be related to the compactness and high density of buildings in the cities, which requires further research. This study also showed that the surface temperature is affected by urban morphology and distance from green space. The research opens new field for future researches.
Spatial planning with regard to military defense
Ebrahim Amou; Ahmad Pourahmad; Seyyed Abbas Rajaei
Abstract
Extended abstractIntroductionCivilians and cities have always been affected by war. However, World War II was the first war in which military strategies succeeded in systematically destroying cities and killing civilian populations on a large scale. It was no coincidence that atomic bombs were also dropped ...
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Extended abstractIntroductionCivilians and cities have always been affected by war. However, World War II was the first war in which military strategies succeeded in systematically destroying cities and killing civilian populations on a large scale. It was no coincidence that atomic bombs were also dropped on cities. In the eyes of policymakers and experts, urban safety and security is one of the most basic assumptions of the global community for human-centered planning. Humans have always faced threats in their lives and constructions and have experienced all kinds of accidents throughout history. One of the basic ways to prepare for crises is to be aware of the degree of vulnerability of the city, especially residential buildings, in case it occurs. Therefore, knowing the degree of vulnerability of urban buildings caused by threats, it is possible to increase the preparedness against any threat to a great extent by adopting strategies. Identifying the risk of possible damages plays an important role in prevention and preparation to face and deal with the negative effects of urban threats and is very important in terms of controlling human and financial damages.Materials & MethodsIn this research, considering the theoretical issues and the examination of global experiences regarding the vulnerability of residential areas against invasion, vulnerability criteria were extracted and completed using the Delphi method. After selecting the criteria and sub-criteria for weight calculation, using the Dematel method, factors that are effective in residential vulnerability have been used. The main goal of the Delphi method is to achieve the most reliable consensus of a group of experts' opinions through a series of focused questionnaires with controlled feedback. By obtaining the consensus of a group of experts through this process, researchers can identify and prioritize issues and develop a framework for their diagnosis. In this research, Delphi panel members were selected as non-probability and combination of targeted or judgmental and chain methods. In this research, Kendall's correlation coefficient was used to determine the level of consensus among panel members. The value of this scale is equal to one when there is complete coordination and zero when there is no complete coordination. Kendall's correlation coefficient for this research was equal to 0.67, which can be trusted as a relatively moderate to high value according to the order of its factors. Building a network analysis process model requires knowing the relationships and interactions between the criteria and sub-criteria of the problem in order to create the most realistic state of the network, which was extracted in the previous stage through Dematel and with the opinions of experts. ANP includes determining the final weights using the method of extracting weight vectors and forming hypermatrix. Results & Discussion,The way of distribution of buildings in terms of floors and especially high-rises has created a special spatial system that has overcome all other urban elements and has turned the city into a compact structure. In terms of the quality of the houses, it can be said that due to the presence of dilapidated structures in the central part of the city as well as informal settlements in the peripheral areas, these houses are not of good quality and are highly vulnerable.From the point of view of passive defense, the passageways and the ability of the network to access the space and the conditions of sheltering are of special importance. Examining the map of vulnerability caused by the access network and access to open spaces in the residential areas of Tabriz shows that the central areas have narrow roads and high density and have high vulnerability. In discussing the vulnerability of residential areas in this research, population density and building density have been considered. By increasing population density in vulnerable areas with specific dimensions, the number of vulnerable population increases. According to the vulnerability map caused by the density of residential areas in Tabriz city, the population distribution is not the same throughout the city and dense population tissues are often located in the central areas and in the range of peripheral tissues (northern parts of the city) and are of high vulnerability. Has Distance and proximity to danger centers is very important in terms of passive defense. The location of these risk centers in the vicinity of human settlements makes it necessary to respect the privacy of these centers. The map of the privacy of dangerous centers in Tabriz shows that the residential areas of Tabriz are not in a good condition in terms of respecting the privacy of high-risk centers and will be highly vulnerable in the event of an attack. The access map of residential areas to relief centers in Tabriz city shows that the distribution of these centers is not balanced in all parts of the city and is mostly concentrated in the central parts of the city, which causes many problems with the influx of people in the event of a crisis. will face these centers. After the occurrence of crises, especially air raids that destroy people's shelters, the temporary accommodation of people is very important. One of the temporary accommodation centers that are considered are educational centers. Also, nowadays spaces are considered as multi-purpose parks and sheds that are used in normal conditions and are considered as temporary accommodation centers in times of crisis. The map of temporary accommodation centers in the city of Tabriz shows that, firstly, these centers are not evenly distributed in all parts of the city, and secondly, they do not have enough numbers according to the existing population. ConclusionMaps and research findings show that the residential density criterion with a weight of 0.356 is in the first place among residential vulnerability factors in Tabriz city. The second rank is assigned to the criterion of residential context with a weight of 0.257. Access criteria, access to relief centers, privacy of danger centers and temporary accommodation are in the next ranks respectively.
Mohsen Ahad Nejad Roshti; Shahrivar Roustaei; Mohammad Javad Kameli far
Abstract
Urban road network is one of the most important urban arteries which has a significant impact on the relief and rescue operations, the evacuation of the injured and harmed people, especially after the crisis. Therefore, assessing the vulnerability of urban road network and planning to reduce these ...
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Urban road network is one of the most important urban arteries which has a significant impact on the relief and rescue operations, the evacuation of the injured and harmed people, especially after the crisis. Therefore, assessing the vulnerability of urban road network and planning to reduce these harms is necessary. This descriptive-analytical research was conducted with the aim of evaluating the urban road network against earthquake by crisis management approach in region 1 of the city of Tabriz. In order to assess the vulnerability of urban road network of Tabriz region 1, three criteria of confinement degree, density, and constructional characteristics were selected. The density criterion includes the sub-criteria of population density and constructional density and the criterion of building characteristics includes five sub-criteria ofage of the building, the quality of the building, type of use, occupation level and type of materials. Each one of these sub-criteria has several sub-criteria as well, which were evaluated by Delphi method. Finally, after assessing the vulnerability of the roads in each sub-criterion, the layers were overlaid by the Multi-criteria Evaluation (MCE) method in the form of IDRISI software. The final results indicate that the vulnerability of the study area roads network (excludingthe newly built neighborhoods) is more than moderate, and is mostly high and very high.The vulnerability of the roads networkis more common in informal residential neighborhoods which should be considered as a priority in planning.
Ehsan Modiri; Gholam Ali Kamali; Sohrab Hajjam
Volume 22, Issue 88 , January 2014, , Pages 75-80
Abstract
Solar radiation is one of the most important and influential parameters in thermal balance of the atmosphere and thus it is considered to be the basis of many climatic studies. Evapotranspiration is defined by the amount of available energy for evaporation. Since energy at ground level is mostly supplied ...
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Solar radiation is one of the most important and influential parameters in thermal balance of the atmosphere and thus it is considered to be the basis of many climatic studies. Evapotranspiration is defined by the amount of available energy for evaporation. Since energy at ground level is mostly supplied by the sun, many researchers have been interested in the influence of solar radiation on agriculture and especially irrigation sciences. Main research variables include total radiation received at ground level and the slope of radiation changes which are calculated and analyzed using data quality control and routing methods recommended by World Meteorological Organization, and measured at two different geographical points with semi-arid climate. Regarding Pearson correlation coefficient, the significance level of Kermanshah station was set at 99% and Tabriz was set at 95%. Total annual radiation and statistical period are positive related. With an increase in statistical years, annual radiation increases with an appropriate slope which shows the ascending trend of annual radiation in stations.
Seyyed Hossein Mir Musavi
Volume 19, Issue 73 , May 2010, , Pages 74-77
Abstract
One of the most important problems in the field of agricultural activities is water scarcity or water resources issues. In this context, only those countries that utilize scientific methods in supplying the water needed for crops have been able to overcome these problems. In this study, we tried to evaluate ...
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One of the most important problems in the field of agricultural activities is water scarcity or water resources issues. In this context, only those countries that utilize scientific methods in supplying the water needed for crops have been able to overcome these problems. In this study, we tried to evaluate the application of meteorological studies in estimating the water requirements of the desired crops (wheat and potato) in Tabriz region during different stages of growth. For this purpose, the ETP (plant evapotranspiration potential) was first determined using long-term statistics, and then, using the FAO organization tables, the plant coefficients for each of the crops were extracted. Finally, in order to plan for the supply of water resources, the effective rainfall in the region has been studied, and by subtracting the amount of water required from effective rain, the amount of water deficiency in the region has been identified.
