Showing 733 results for Type of Study: Research
Shamsollah Asgari, Amir Safari, ,
Volume 18, Issue 50 (3-2018)
Abstract
One of the important and effective factors in the destruction of natural resources is the flood phenomenon, identification of this phenomenon and effective parameters in flood occurrence in natural resources and catchment areas is necessary. The purpose of this study was to determine the flooding of sub-basins in Jafarabad basin in Ilam province. In this research, the Jafarabad basin in Ilam Province is divided in to 12 sub-basins. For each sub-basin, 28 geometric, climatic, permeable and physiographic parameters such as area, environment, length and slope of main stream, length and slope of the basin, time of concentration, The coefficients of shape and variability of precipitation, vegetation cover, CN, discharge and ... have been calculated using GIS software. Factor analysis was used to determine the flood potential of the sub basins. The data of 28 sub-basin variables were analyzed by SPSS software and summarized in 5 main factors (shape, flow, slope, drainage and runoff). The results indicate that the factor of the form with a specific value of 11/30 is the most important factor in the flooding of the studied basin. Channel, slope, drainage and runoff factors with a specific value of 7.21,4.34,3.22 and 3.10 respectively Priority is in the next rank. Then, based on the factor scores of the study area, three large, medium and low flooding categories were mapped and a zoning map of the flood potential of the sub-basins was drawn in the GIS environment. Sub-basins (9,8,5,3) in the shape of the sub-basins (1,6,11) in the gradient factor, sub-basins (2, 7) in the drainage factor and in the runoff factor of the sub-basins (4,10,12 ) Have a lot of flood potential. In sub-basins, the similarity of flooding, erosion, vegetation, and human performance impacts is divided into 3 groups with high, medium and low flood potential. Sub-basins play a major role in the flooding of the basin, which affects the vast agricultural fields of the lower reaches.
Fatemeh Mohammadyary, Hamidreza Pourkhabbaz, Hossin Aghdar, Morteza Tavakoly,
Volume 18, Issue 50 (3-2018)
Abstract
Land-use change is one of the most important challenges of land-use planning that lies with planners, decision-makers and policymakers and has a direct impact on many issues, such as economic growth and the quality of the environment. The present study examines the land use change trends in Behbahan city for 2014 and 2028 using LCM in the GIS environment. Analysis and visibility of user variations, carried out in two periods of Landsat satellite images of 2000 (ETM + sensor) and 2014 (OLI sensors), and land cover maps for each year. The transmission potential modeling was performed by using the multi-layer perceptron artificial neural network algorithm using six independent variables and the distribution of changes in user usage were calculated by Markov chain method. The results of the prediction showed that the most reduction in the changes is the degradation of the rangelands and the greatest increase in the area of agricultural use. According to the horizontal tabulation results of the 2028 map, it can be stated that from the total area of the area 28336.22 hectares of land were unchanged and 33223.78 hectares of land use change. Also Rangeland and forest degradation during this time period can be a danger to urban planners and natural resources.
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Dr Abazar Solgi, Dr Heidar Zarei, , ,
Volume 18, Issue 50 (3-2018)
Abstract
Estimating and predicting precipitation and achieving its runoff play an important role to correct management and exploitation of basins, management of dams and reservoirs, minimizing the flood damages and droughts, and water resource management, so they are considered by hydrologists. The appropriate performance of intelligent models leads researchers to use them for predicting hydrological phenomena more and more. Therefore, in this study, the Gene Expression Programming (GEP) and Support Vector Regression (SVR) models were used to model monthly precipitation of Nahavand City. In this study, precipitation, temperature, and relative humidity data were used in a 32-year period (from 1983 to 2014). The results showed that the same and good performance of both models (R2= 0.92), but according to different evaluation criteria, GEP model showed a little better performance (RMSE= 0.0478 and 0.0486), while the running GEP model is so easier than the SVM model. Totally, it can be said that GEP model had been suitable for modeling monthly precipitation of Varayeneh station in Nahavand City. Finally, the monthly precipitation was predicted the GEP which showed a decrease in precipitation in compared with previous months.
Hossein Asakereh, Robab Razmi,
Volume 18, Issue 50 (3-2018)
Abstract
In the present study, the main aim was the spatial evaluation summer rainfall of northwest of Iran based on30 stations in northwest of Iran during 30 years of statistical period (1985-2014). An attempt, using geo-statistical modeling by ordinary least squares (OLS) and geographically weighted regression (GWR) procedures, was also made. The results represented that the GWR model with higher S2, lower residuals and lower RMSE is an optimized geo-statistical model for rainfall modeling of this area. This model can explain spatio-temporal rainfall distribution in northwest of Iran in a diversified topographical and geographical background. This model revealed that two spatial factors including elevation and slope, have the most important role in the summer rainfall behavior.Therefore Elevations in the mountainous and eastern parts of Lake Urmia, Latitude in the northern regions and slopes in the east of the region, have the most role in the spatial variations of summer precipitation in northwestern Iran.
Hujjat Mirzazadeh, Taher Parizadi,
Volume 18, Issue 50 (3-2018)
Abstract
Introduction and Objectives: Unbalanced distribution facilities and services on Economic, Social and between regions, need to the planning and balanced spatial development the spatial structure of the country is inevitable This study aimed to determine the level development of the provinces of Iran and rank them based on the level of development and different levels of development of the country From 1345 to the present to help make the planning system and national policy has been done.
Methods: This study is based on cognitive research and in terms of the goal of the evaluation research method - comparative. The population according to the latest political divisions of 31 provinces and indexes evaluated 33 indicators in four dimensions (Economic, infrastructure-physical, socio-cultural and health), respectively. For data analysis, factor analysis and cluster analysis techniques were used.
Findings: The results show, between the provinces in terms of development, there are differences and inequalities. So that in Tehran alone during the decades the highest level of development and Sistan and Baluchestan province are the lowest and most disadvantaged. Comparison provinces during different periods of development of the center over the periphery of inequality.
Conclusion: According to the results of research to reduce disparities between provinces The placing of the country due to the talent and potential of each region and prioritizing disadvantage and less developed provinces in the planning of regional demands.
Mrs Faranak Bahrami, Mr Abbas Ranjbar.s.a, Mr Ebrahim Fattahi,
Volume 18, Issue 50 (3-2018)
Abstract
Probable maximum precipitation (PMP), is the highest rainfall, which occurs at a given time in a basin. Hydrologist calculates the probable maximum flood for the design of overflow dams, by using the PMP, with two methods: statistical and synoptic. The purpose of this study is calculating PMP in the Ghomrood basin by using the synoptic method. For this purpose rain, meteorological data of the Iran’s Meteorological Organization were used. Also, the data on the 850 and 500 hPa levels were analyzed by the National Center for Environmental Prediction and the National Center for Atmospheric Research (NCEP-NCAR). In the following, the required synoptic maps produced and were studied. Iso rain maps were drawn, and depth-area-duration curves were determined. Eventually, PMP was estimated at 24, 48 and 72 hours. So that 24 hours PMP, by calculating 50 and 100 years return period of dew point estimated 51/75 and 54 mm respectively. Also for 48 hours PMP 128/25 and 132/05 mm, and for 72 hours PMP 97/9 and 101/75 estimated.
Hassan Afrakhteh, Mohammad Hajipur, Farhad Javan,
Volume 18, Issue 50 (3-2018)
Abstract
The oil has gradually obtained a predominant place in national economy since 1950 and nowadays, is the main important resource securing country financial needs. Two questions are the base of this research regarding contradiction of oil rent and traditional economic sectors including agriculture and livestock rearing which always have been intensified. These two questions are as follows: what are the impacts of oil wealth distribution among different regions on Iran's rural economic structure? What has been the locational-spatial consequences of this oil wealth distribution on agricultural sector as a main element of Iran's rural economic structure? Research required data have collected based on document study on the country during 2006- 2011. Collected data are analyzed based on Shift-Share Analysis and Gibbs- Martin methods. Result show that there have not been any incentive in the local, regional and national management for strengthening rural economic structure using oil wealth. In addition, absence of industrial sector in rural economic structure with emphasis on agricultural sector both from policy making view and credit securing show that there have not been any logical sight on the political economic system facing rural space economy for development.
Morad Kaviani Rad, Hadi Aazami, Majid Rasouli, Ahmad Bakhshi,
Volume 18, Issue 50 (3-2018)
Abstract
Fundamentalism is one of the security issues of today's world, and the Territorialize and , Territoriality of fundamentalist terrorist groups has attracted a large part of the world's security literature. Over the past decade, Southwest Asia and North Africa have emerged from domestic crises and transnational power interference, the focus of the emergence and expansion of radical ideas that impose huge costs on the regional and trans-regional countries of the world. Meanwhile, the northern continent of Africa, and in particular the country of Libya, as a fragile state emerging from the internalities and role of the regional interventionist powers, has provided opportunities for the expansion of ISIS's fundamentalist organization.The present study is based on the descriptive-analytical nature of the hypothesis that based on internal factors such as strategic position and huge oil resources, the crisis of legitimacy, spatial inequalities (axis-margin), the weakness of national correlators, weakness of central government power, Interventions of regional and global powers territoriality have been provided a platform for fundamentalist organizations such as ISIL in Libya, and the data and information required for research has been compiled in a library-based way . The results of the study showed that the fragility of the government in North Africa, in particular Libya, Territorialize and , Territoriality grounds have provided for ISIL's .
Mohammad Daraei, Dr Peyman Mahmoudi, Dr Behroz Sari Sarraf, Dr Ali Mohammad Khorshiddost,
Volume 18, Issue 50 (3-2018)
Abstract
Agricultural sector is most dependent on climate, and climate is the main determinant of time, location, production resources, and productivity of agricultural activities. The first event of zero-degree temperature in fall and its last event in spring is important for agriculture. This information is used to determine the species suitable for planting in each area. The present study seeks to identify the probability distribution function for extracting statistical characteristics of frost events in Iran. For this purpose, the history of early autumn and late spring frosts were extracted using daily minimum temperatures of 44 synoptic stations in Iran for a period of 30 years (1981-2010). After fitting various distributions, the best distribution was selected using Anderson-Darling goodness of fit test. Results indicated that most stations follow the Wakeby distribution. Based on the calculations, the first day of frost occurs in the highlands of the Northwest (Saqez, Hamedan, Ardabil, and Zanjan), Northeast (Bojnoord, Torbat-e Heydariyeh, Birjand, and also the Central Zagros Mountains (Shahr-e Kord), due to proximity with cold lands of the North such as Siberia and Northern Europe as well as early entry of westerly winds to this region compared to other regions of Iran will occur. And the latest event of the first day of frost occurs a little farther from the southern coast of Iran in a narrow strip along the coast and parts of the northern coasts (from Babolsar to Bandar Anzali). The earliest event of the last day of frost occurs in the same area in early February. The latest day of frost in Iran occurs in Azerbaijan, Kurdistan, Khorasan, and highlands of the province of Chahar Mahal and Bakhtiari
Adel Nabi Zadeh Balkhanloo, Zahra Hejazizadeh, Parviz Zeaiean Firoozabadi,
Volume 18, Issue 50 (3-2018)
Abstract
Continuous decline in Lake Urmia water levels In recent years, the decline of rainfall and river flows and constant droughts has become the main concern of the people and the people. To study climate change and increase of temperature in the catchment area of Lake Urmia, two factors for measuring the temperature and properties of satellite images were used which indicate the importance of land surface temperature changes (LST) and normalized vegetation differences (NDVI). This study was carried out using the satellite data of the periodic watershed (2008-2008) to investigate the spatial relationship between NDVI-Ts and NDVI-ΔT to investigate the actual agricultural drought occurrence. The goal is to extract the VTCI (vegetation temperature index) index, which is capable of identifying drought stress at regional scale. The results showed that the slope is negative for the warm edge, where it is positive for the cold edge. The gradient gradient shows that the maximum temperature is reduced when the NDVI value increases for any interval. The slope on the cold edge indicates that the minimum temperature rises when the NDVI value rises. Overall, at the warm and cold edges, it has been observed that the drought trend over 2009-2008 is higher than in 2010. In the days of Julius Day 257, the slope of the cold edge from 2008 to 2010 is decreasing. But at the hot edge, intercept pixels for 2008 is more than 323 degrees Kelvin, where in 2009-2010 it is less than 323 degrees Kelvin. In general, the correlation coefficient (R2) is different in the TS-NDVI spacing between (0.90-0.99). The present study showed that with the integration of satellite satellite data with meteorological data, the VTCI threshold for drought stress varies from year to year depending on the data conditions.
Ali Asghsr Abdollahi, Moslem Ghasemi,
Volume 18, Issue 50 (3-2018)
Abstract
Analysis probative spatial data method for checking patterns spatial accidental and accidental is distribution variables spatial and correlation spatial from more usage and more important tools Analysis for is the research in the case spatial data. The aim in research, is evaluation operation methods find inside in distribution spatial land use city Kerman. That on base of methods find inside kriging ordinary with models circularly, gauss, spherical and exponential for find inside data use and with criteria error inclusive Root Mean Square) RMS( and Standard Root Mean Square) SRMS(,Mean Standard)MS(,Mean and average Mean error)ASE (pay to evaluation veracity and exactitude. Methodology research present, descriptive – resolution with resolution spatial use software GIS. Results resolution explanatory existence pattern cluster in the land use study, administrative and commercial and pattern diffused for land use medical in the city Kerman. In between four pattern use study follow of better order. Too results research rectitude, specified pattern kriging ordinary with model gauss beater shape pattern distribution spatial use in the city Kerman
Sayad Asghari Saraskanrood, Zeynab Dolatshahi,
Volume 18, Issue 50 (3-2018)
Abstract
Alireza Entezari, Fatemeh Mayvaneh, Khosro Rezaie, Fatemeh Rahimi,
Volume 18, Issue 51 (6-2018)
Abstract
Human thermal comfort and discomfort of many experimental and theoretical indices are calculated using the input data the indicator of climatic elements are such as wind speed, temperature, humidity, solar radiation, etc. The daily data of temperature، wind speed، relative humidity، and cloudiness between the years 1382-1392 were used. In the First step، Tmrt parameter was calculated in the Ray Man software environment. Then UTCI and PMV index values were calculated using Bioklima software. The results showed that the most severe cold temperature stress on PMV index is in the winter and late autumn and UTCI index in January and February are the coldest stress. The power of neural networks, prediction of future performance network (generalized orientation) it simply is not possible and the new model presented in this paper have been restricted Boltzmann machine-based neural networks or neural networks is used deep belief. Using this structure, metrics Mean Squared Error (MSE) and mean absolute percentage error (MAPE) benchmark ate for seven indexes derived from data gathered by three factors related to the occurrence of weather conditions and other indicators of thermal comfort of human the system was evaluated. Assessment by dividing the data into training and testing parts, and the ratios have been of two-thirds, fifty percent and one-third And two benchmark MSE and MAPE were calculated. The proposed system performance in forecasting the human thermal comfort is desirable.
Dr Mohammad Mahdi Hoseinzadeh, Dr , Mis Sepide Imeni,
Volume 18, Issue 51 (6-2018)
Abstract
The process of precipitation – runoff of each basin, is influenced by hydrologic, geomorphology conditions, geological formation and vegetation. There are different methods in drainage basins. One way to estimate the runoff height is Curve Number (CN) method. That reperesents the hydrological behavior of basin. data were collected for statistics of climate and then topographic map of 1: 25000 and geological map of 1: 100000 by GSI was used. Smada software for calculate the short – term rainfall at different return periods. As well as Arc GIS software for mapping Curve Number by combining maps of land use, soil hydrological groups and moisture of soil with using the table of America Soil Conservation Service (SCS). And then modeling related in the GIS mappings of runoff height of Hesarak catchment was prepared. The aim of this study, was to determine Curve Number and estimate runoff coefficient and maximum discharge runoff with SCS method in various units catchment is. The results showed, hydrologic condition and soil hydrological groups are the most important parameters to determine the CN and affect on runoff. The most potential for runoff is in downstream of basin that specified with urban land use. Also average weight of Curve Numbers those obtained for each sub catchments, Chapdareh sub catchment (S2) with 88 Cure Number and mean of runoff 28.15 mm had the highest volume of runoff, Dochenaran sub catchment (S3) with 89.3 Curve Number and mean of runoff 24.54 mm and sub catchment of the twin branches (S1) with 90.1 Curve Number and mean of runoff 17.36 mm had The lowest amount of runoff probability and spill potential. But in general potential runoff in this basin is relatively high. The maximum amount of runoff Curve Number in condition of high humidity is 99 and 78 is the lowest.
Farzad Karimi, Mostafa Ahmadvand, Ali Heidari,
Volume 18, Issue 51 (6-2018)
Abstract
This study aims at identifying optimal method for masuring degree and level of development with resprct to models commonly used (Taxonomy, TOPSIS, Moris, SAW, and VIKOR). It is an applied rsearch in terms of the purpose and also is a quantitative research that was carried out in a survey method. Statistical population of the study was the villages in the county with 20 or more households (89 villages). Accordingly, 566 rural households were determined and selected as a sample using Lin sample size table. To collect the data, a questionnaire was used. For determining the content validity of the questionnaire, a factor analysis and for internal consistency reliability, Cronbach's alpha was used. The Cronbach's alpha coefficient (0.561-0.955) indicated the optimality of the questionnaire. Matlab 7.10, Excel2010, SPSS20, and Arc-GIS Softwares were used for modeling the level of rural development in the county. Findings revealed that there was high significant relationship between the methods with regard to their ranking scores. Findings showed that the VIKOR was a suitable and powerful approach to determine level of rural development in the county. In VIKOR, the range of development degree was very high with compaire to other methods. In VIKOR similar to TOPSIS, negative and positive ideals were considered. VIKOR has a differenc with TOPSIS in considering criteria weight, In VIKOR at first, distance of each criterion from ideal was calculated, then the weights were added them. Therfore, in VIKOR against SAW and TOPSIS has a high sensivity to the weights. Furtermore, findings showed that Sarabtaveh, Deh Bare- Aftab Olia, and Tangary with regard to 51 criteria by 0.635, 0.608, and 0.579 scores, respectively were developing villages and Gavbarg, Cheshmeh Tabarghoo, Tal-Gahi with 0.182, 0.201, and 0.233 scores respectively were non-developed villages. Also, there wasn’t any village in level of completely undeveloped, developed and completely developed. Also, approximately half of villages (46.1 percent) with 21.46 percent of the population of the rural region were undeveloped villages. In addition, 69.35 percent of population in villages of the study was in developing stage.
Ali Ahmadabadi, Zahra Sedighifar,
Volume 18, Issue 51 (6-2018)
Abstract
Climate change is one of the most important challenges that has affected various parts of human life on Earth. In the present study, in order to investigate the climate change, three synoptic stations of Karaj, Mehrabad and Dashan Tepeh with the help of the statistical statistic downscaling model (SDSM) model were used to predict the statistical period of 2016-2045. Finally, the effects of climate change on the hydrologic conditions of the basin with the help of the model (SWAT) was simulated by the Soil and Water Assessment Tool. The amount of surface runoff and runoff at the study area is 10.59 mm in the studied observation period, but this rate was estimated to be 21.27 mm for the predicted period due to the increase of urbanization and changes in utilization. The results of the research, while highlighting the importance of the effects of climate change, are necessary for their application in applying proper management to adapt to climate change in the future policies of the basin management.
Mrs Masooume Darmani, Mohammad Nohtani, Haydeh Ara, Ali Golkarian, Salman Sharif Azari,
Volume 18, Issue 51 (6-2018)
Abstract
One of the most important processes of erosion and sediment transport in streams is the river most complex engineering issues.this process special effects on water quality indices, action suburbs floor and destroyed much damage to the river and also into the development plans Lack of continuity sediment sampling and measurement of many existing stations. due to the low number of hydrometric stations in Iran and the lack of continuity of sediment sampling and measuring in many existing stations, on one hand the exact amount of sediment load in many rivers in the country is not available and because of differences in climatic, hydrological and topographical conditions in the country, on the other hand, the preparation and calibration of sediment Erosion Models different regions, is unavoidableCalibration models of erosion and sedimentation in different locations is difficult and requires financial capital andthe time . the But evolutionary optimization algorithm able to resolve this problems of mathematical and experimental methods in this paper, a new optimization algorithm spiders can be made to education And the evolutionary pattern for input (discharge and precipitation) and rain-gauge gauging stations and Watershed Kardeh designated evolutionary algorithms and artificial network performance for 24 year 24-year dam catchment Kardeh for the period studied. In conclusion, the results proved that social spiders optimization algorithm t better resultspredic to for sediment in watershed Kardeh
Rasoul Heidari Sourehjani, Ahmad Ali Beigi,
Volume 18, Issue 51 (6-2018)
Abstract
At present, one of the issues of all cities is the urbanization and, consequently, the development of urban reptile tentacles on parakeet lands, the consequences of which are: Marginalization, destruction of agricultural lands, population growth of cities, failure to respond to certain services and utilities in the city, physical tissue fractures, environmental problems, especially pollution and urban disruption. In recent years, urban sprawl in many cities of Iran particularly, the boundaries of cities are affected by the urbanization process and the need of citizens. New housing has been transformed into user data and land. Considering that the city of Rasht is similar to other cities in recent years, there has been an increase in population, and has made significant changes in the use of urban land in this city. The present study seeks to evaluate the landslide changes in Rasht city during the years 1998-2016, using different patterns. Hence, to find out the type and extent of changes in the data and the factors influencing urban growth in the above area from the available AutoCAD files, detailed plan of Rasht city and also from Landsat TM imagery to measure urban growth in different directions from the hot spot of all urban users based on the proximity and the area, the results are shown Which has the user density to different levels and the breadth of applications in development and urban growth has played a significant role. Also for horizontal expansion of the city Fuzzy and Cause pattern and Markov chain network in Edrisi software is evaluated and shows that over the course of 18 years Rasht area was 4941.76 hectares It reaches 6202 hectares and represents 1260.243 hectares.
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Mostafa Karimi, Mahnaz Jafari, Faramarz Khosh Akhlgh, Saeed Bazgir,
Volume 18, Issue 51 (6-2018)
Abstract
Spatio-temporal variations of factors affecting the occurrence of precipitation can lead to a change in its amount. The atmospheric moisture is one of the most important factors for precipitation formation. In this study, changes in atmospheric moisture and its relation with occurrence of seasonal wet and dry periods were investigated in Iran. The re-analysis data from the ERA interim European Center for Mid-Term Projections (ECMWF) was used during the period 1981-2011. The z index (ZSI) was used to extract wet and dry periods of autumn, winter and spring seasons. The seasons with the maximum percentage of wetness/drought occurrence during the above periods were selected. Vertical integrated divergence of the moisture flux was extracted in three layers of the lower, middle and upper atmosphere above Iran. The results revealed that in all three layers, moisture flux was maximum during wet period and decreased in dry one. In all layers in wet and dry periods, the moisture content imported to Iran increased during warm season as compared to cold seasons. In addition, the difference in moisture content in the warm season was less than cold seasons and has less variations. There was no significant changes in moisture at high levels in three seasons. In general, there was a significant difference in terms of the winds pattern in the wet and dry periods. The favorable conditions of flow patterns on the water surface of the region provide the condition for increasing transport of moisture to Iran. Although, the moisture transfer reduced due to deviation and change of direction of currents, in dry period especially in the lower layer, and hence increase the occurrence of dry periods in Iran.
Parviz Kardavani, Farideh Asadian, Mohammad Reza Fallah,
Volume 18, Issue 51 (6-2018)
Abstract
Indiscriminate exploitation of underground aquifers shahriar Plain loss of ground water in the region has created. Water penetration can increase the volume of groundwater reservoir and reduce the loss of it. One way of artificial recharge of aquifers, infiltration of water from riverbeds or running water. In this study, we have tried By examining the characteristics of Karaj River and its flood flows, parameters infiltration GIS examined, For this purpose, The different factors affecting this environment GIS to prepare maps of each factor was prepared. Then using acquired the weight of each layer map by weighted factors to locate the combine And using Boolean logic final map in two classes and is not appropriate was prepared. by matching the map obtained with the river Karaj identified were Due to Construction Dam Amir Kabir And the supply of drinking water in Tehran harvest Abundant by pools traditional and modern Drbaladst Karaj River, Karaj River with flood flows its role Lower in improving groundwater Shahriar Plain is capable.
