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Showing 177 results for Mohammad

Mohammad Saligheh, Mohammad Hossein Nasserzadeh, Thmineh Chehreara Ziabari,
Volume 16, Issue 43 (16 2016)
Abstract

In this research, the relationship between NCPI and CACO indices with autumn precipitation of Southern Coast of Caspian Sea (SCCS) was investigated. In this regard, two sets of data were used (Aphrodite and Station). And the days with more rainfall than long-term average rainfall station and on condition that the rainfall is more than 70% of the region rainfall, were chosen as a day of widespread rainfall. The sea level pressure data was extracted and by cluster analysis and coalition method was clustered. Then, a representative of the widespread precipitation days from station dataset was selected, investigated and analyzed accordingly. The results state that within all patterns there exists a high pressure on the upper side of the Caspian Sea, or a margin of high pressure is extended on to the sea itself. These high pressure regions have relatively cold nature that can cause currents in the northern direction while intersecting with the relatively warm water during the summer. These currents can absorb moisture during their motion towards south which can lead to their instability. In addition, one should not forget the fact that in each three investigated patterns, dynamic factors at high levels have intensified the abovementioned phenomenon and enhanced the instability, which as a result brought about widespread precipitation. Continuously, the abovementioned Remote bond indices were extracted on a daily basis and their relation to north coast widespread rainfalls was studied, which came to a meaningful relationship between these index sets and fall index sets. The relationship is direct with NCPI or surveyed stations, and it’s an inverse relationship with CACO. On the other hand, the study of indexes anomalies on the days without rainfall and with rainfall was done by One Way ANOVA and Tukey test. The result was a meaningful index anomaly on the days with and without rainfall.


Jalil Mohammadi, Alireza Mohammadi,
Volume 17, Issue 44 (3-2017)
Abstract

Social capital including values such as trust and cooperation and solidarity in a residential zone is a concept that has been very important and critical in the process of urban renewal in recent decades. The aim of the present study was to measure the degree of social capital and to investigate the relationship between social capital and physical interference pattern and continued motivation of residence. And it also tries to identify the type and extent of the relationship between social capital with the increased participation and the rate of the implementation of urban renewal projects, on the other hand. The present study is a survey –based research. It is descriptive - analytical. The conceptual questionnaire was used as an instrument in this study. Formulation of theoretical foundation was based on library resources. The population of the present study consisted of all the inhabitants living in Zanjan old texture (family heads) that was 46150. Using multi-stage random sampling was used and 330 samples were selected using Cochran formula. The results showed that the Zanjan old texture residents have the social capital above average; nearly it was true in all of its components. Also significance relationship does not exist between social capital and the renewal of old urban texture. Due to various factors including lack of trust in the body of urban management, lack of reinforcing the planning of required effective variables, residents are uncertain and in doubt on the issue of renewal and improvement of urban old texture. So, it emphasizes on the importance of planning in this area.


Mohammad Hasan Yazdani, Afshar Saidain ,
Volume 17, Issue 44 (3-2017)
Abstract

At the moment with regard to geopolitical and geostrategic situation of Iran, the existence of countless underground resources and the formation of ideological state, unfortunately, in urban areas of the country, especially in Ardabil ,because of its proximity to the border of northern and northwestern borders with knowledge of this particular situation, economic and infrastructural projects, Infrastructures and installations have been made without observing and interference of considerations and defense and security arrangements and have become a bare and significant available target for enemy and invading countries. This research aimed to study the vulnerability of Infrastructures Ardabil in terms of passive defense and application - development approach in a descriptive and analytical way using 18 effective indicators in form of 5 components of "Lifeline", "crisis management Centers", "military and police centers", "Urban equipment" and "support centers" in three priorities of strategic, psychological and support destruction. Information gathered in the Super Decision software (network analysis) are weighted, then mapped in GIS environment. The results of the studies show that there are six major hazardous zones under crisis conditions and are prone to injury in the Ardabil that the most important of them are the northeast output of Ardabil (Jahad field leading to Astara gate), the southwest of Ardabil (Sarein station leading to the Basij field toward the Sham Asbi village) and finally the north and northwestern parts of Ardabil (Vahdat square), with the sum of (17% of the total land area of the city) have included the highest vulnerability, due to the poor conditions of the physical characteristics and focus on management, corporate, military and state entities in this regions of the Ardabil city.


Alimohammad Khorshiddoust, Behrooz Sarraf, Bagher Ghermez Cheshmeh, Mrs Fatemeh Jafarzadeh,
Volume 17, Issue 47 (12-2017)
Abstract

In recent years, the severe fluctuations in precipitation have affected various parts of the country. On the southern coasts of the Caspian Sea, precipitation as one of the important climatic parameters has undergone changes due to global climate change. In the present study, we tried to evaluate the effect of climate change on rainfall in this region by applying a suitable model. In this study, observational period rainfall (1961-2001) was analyzed. the output of the HadCM3 model was used. At first, seven synoptic stations were selected and their data were analyzed in terms of accuracy, and length of statistical period, and lost data was restored. The AOGCM data were simulated using the SDSM model and the rainfall values were simulated for the observation period. After confirming the matching of the simulated data with observational data, the values of the Future (2039-2011) is estimated. The estimation errors of the SDSM model were calculated monthly by MBE and MAE criteria, and then compared. The output of the SDSM model was used to study the total annual precipitation in days with rainfall of more than 1 mm in the observation period and the upcoming period (2011-2039) by the R-Climdex model and the values of the PRCPTOT index Became zoning in the Future. The results showed that the model error in season with high rainfall is more than seasons with low rainfall. On a monthly scale, the maximum error occurred in the months of September, October, November and December. The maximum error in the fall and the minimum error was calculated in the spring and April and May months. According to the results, the total annual rainfall in the period of 2039-2011 will decrease in Anzali, Babolsar, Gorgan and Noshahr stations and rainfall will increase in stations of Astara, Ramsar and Rasht. Geographical distribution of selected were 5 sites in the Khuzestan, 20 sites in Bushehr, 24 sites in Hormozghan and 12 sites in Sistan and Baluchistan provinces. In total, 9000 sites were selected with a 2 km2 were suitable for large scale microalgae cultivation. The total area of these sites were estimated to be 18000 km2. The highest number of proper sites were found in Hormozghan province and lowest numbers of sites were found in Khuzestan province. The availability of technical service, carbon dioxide point resources from oil and gas units are an advantages for microalgae related activities in the Bushehr and Khuzestan provinces. The higher quality of water in the Sistan and Baluchistan province is an advantages for development of microalgae biomass production in the area.
 

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Ali Reza Karbalaee Doree, Sayyed Mohammad Hosseini, ,
Volume 17, Issue 47 (12-2017)
Abstract

Air pollution is one of the most important natural hazards in cities that is one of the priorities of climate research.  In this research, synoptic situation of days polluted by ozone in Tehran have been studied and by environmental to circulation approach and cluster analysis. At first, was formed a matrix in 2417*41. Rows are indicated days and columns represent the number of stations. by cluster analysis and Ward method eight different clusters were identified. The results showed that the frequency of the ozone days have a seasonal trend and more can be seen in the first half of year in these cases the establishment subtropical high pressure in Iran. Therefore, cause the persistency of pollution in Tehran.
 

Dr Javad Sadidi, Dr Hani Rezayan, Mr Mohammad Reza Barshan,
Volume 17, Issue 47 (12-2017)
Abstract

Due to the complexity of air pollution action, artificial intelligence models specifically, neural networks are utilized to simulate air pollution. So far, numerous artificial neural network models have been used to estimate the concentration of atmospheric PMs. These models have had different accuracies that scholars are constantly exceed their efficiency using numerous parameters. The current research aims to compare Elman and Jordan recurrent networks for error distribution and validation to estimate atmospheric particular matters concentration in Ahvaz city. The used parameters are relative humidity, air pressure, and temperature and aerosol optical depth. The latter one is extracted from MODIS sensor images and air pollution monitoring stations. The results show that Jordan model with RMSE of 219.9 milligram per cubic meter has more accuracy rather than Elman model with RMSE of 228.5. The value of R2 index that shows the linear relation between the estimated from the model and observed values for Jordan is equal to 0.5 that implies 50% estimation accuracy. The value is because of MODIS spatial resolution, inadequacy in numbers as well as spatial distribution of meteorological station inside the study area. According to the results of the current research, it seems that air pollution monitoring stations have to increase in terms of numbers and suitable spatial distribution. Also, other ancillary data like volunteer geographic air pollution data entry using mobile connected cheap sensors as portable stations may be used to implement more accurate simulation for air pollution.
 

Mrs Malihe Mohammadnia, Dr Gholamabbas Fallah,
Volume 18, Issue 48 (3-2018)
Abstract

Landslide, due to its dangerous nature in mountainous areas, usually causes morphology to suddenly collapse and causes major damage to residential areas, roads, agricultural lands, and so on. In this study, using the AHP model and fuzzy logic operators, we evaluated and zoned the landslide sensitivity in the Pseudogene basin in Razavi Khorasan province. The eight main criteria of elevation, slope, tilt direction, distance from the waterway, distance from the road, distance from the fault, geology and land use associated with the occurrence of landslide phenomena were examined in total. The sub-criteria were weighted and fuzzy using the Frequency Ratio Model. The weight of the criteria was also determined using the AHP model. Then the landslide susceptibility map was prepared using fuzzy operators 9 / 0.8 / 0 and 0.7 and verified using the ROC curve. The results showed that the gradient factor had the most effect and land use factor had the least effect on the occurrence of slip in the basin. Validation results of the model showed a 90% accuracy of the landslide sensitivity map with a 0.7% operator in the basin. Therefore, the fuzzy gamma model with the 7th operator provides the best form of landslide susceptibility map in the Pseudogene basin.
 


Bakhtiar Feizizadeh, Ali Khedmat Zadeh, Mohammad Reza Nikjoo,,
Volume 18, Issue 48 (3-2018)
Abstract

Remote sensing technology is one of the most efficient and innovative technologies for agricultural land use/cover mapping. In this regard, the object-based Image Analysis (OBIA) is known as a new method of satellite image processing which integrates spatial and spectral information for satellite image process. This approach make use of spectral, environmental, physical and geometrical characteristics (e.g. texture, shape) together images contexts for modeling of land use/cover classes. The main objective of this study is to classify micro land use/cover of Meyandoab County by applying appropriate and effective algorithms and parameters in the object based approach. For this goal, Quick Bird and Aster satellite images were used within the integrated approach for processing and land use modeling. Accordingly, the land use map was classified in 9 class based on spectral and spatial characteristics.  In order to perform OBIA, the segmentation was applied in the scale of 10, shape parameter of 0.7 as well as the compactness of 0.3. In terms of the classification task, fuzzy based algorithm and operators (AND, OR) was applied to detriment the membership functionality of segments for each class as well as classifying the related objects.  We also applied textures, geometric, NDVI, GLCM, brightness algorithms based on fuzzy operators and assign class algorithm. In order to applying the validation of results, the accuracy assessment step was performed and the finally overall accuracy of 93.6 was obtained for the derived map. The Kappa coefficient was also detriment to be 0.92. The area under cultivation included respectively for lands of wheat and barley, prunes and plums, apples, vineyards and alfalfa hay2622.42, 4505, 4354.55, 4457.85, 14110.58 hectares.
 


Naseh Qaderi, Bohloul Alijani, Zahra Hejazizadeh, Mohammad Saligheh,
Volume 18, Issue 48 (3-2018)
Abstract

Wheat is the main focus of the economy of Kurdistan province in which the annual fluctuation of wheat yield is 4/11 times as affected by the climatic elements of the site. This study investigated the role of agro-climatic variables and indices on rainfed wheat yield in Kurdistan province. The data of planting area, amount of production, damages and yield of wheat of 31-year in 10 regions of Kurdistan along with the hourly, daily, decade, monthly, seasonal and yearly levels data of 22 synoptic stations were collected. The correlation between wheat yield and 128 independent variables was calculated. The effect of variables on yield evaluated by multivariate regression. The spatial analysis of variables was performed and the spatial model of wheat yield was introduced for province and regions. The results showed that climatic elements in various regions are different, in a 99% confidence. Most of the independent variables alone have a significant effect on wheat yield, but in the stepwise model, 7 variables such as: the number of rainy days of the year, the sum of the degree hours (of temperature less than -11 ° C) in germination and tilling stage, annual precipitation and the precipitation of November are determinants of the yield. Yield and effective independent variables have significant spatial differences even in a cluster climate type. The highest and lowest coefficient of variation of wheat yield is related to Bijar and Kamyaran areas, respectively. Kamyaran and Sanandaj regions have the highest and lowest yield, respectively. Bijar is the highest risk region of the province for wheat production.


The results of this study showed that with a 99 percent confidence, climatic elements (variables) vary in different regions. Most of the independent variables have a significant effect on wheat yield in simple linear regression, but in Stepwise method, due to the internal correlation between variables, just variables entered that have insignificant correlation with each other and have more effects than other variables. The variables affecting the performance are differentin various regions, and from the point of view of effectiveness, the arrangement of the variables in different areas vary too. In other words, even in two regions with a climatic type (based on the Modified De Martonne method), both agro-climatic indices and wheat yield are significantly different. The impact of effective variables on yield at any time and place depends on the time of year and the phonological stage of wheat. At one time the environmental conditions of different regions in terms of temperature, humidity and precipitation differ, based on phonological stages of the regions. The time of the vulnerability of wheat varies from place to place. Wheat vulnerability at flowering stage is more than other stages. The effect of independent variables on yield at different times of year is proportional to the phonological stage in years Different and different in different regions. In Kurdistan province, the number of rainy days of the year, total degree hours the temperature reaches below -11 °C (sum of hours with below -11 °C temperature) from germination to tillering stage, the annual precipitation, the rainfall in the fifth decade of the water year (the precipitation of 11-20 of November), annual relative humidity and total degree hours the temperature reaches above 30°Ctemperature (sum of hours with above 30 °C temperature) in milky and dough stage is the determinants of the production of rainfed wheat. In Baneh and Marivan areas, the coefficient of variation (CV) is lower and in Bijar and Divandareh regions CV is more than other regions. Kamyaran region has the highest yield, Baneh and Marivan were ranked secondjointly. Sanandaj and then Bijarhave the lowest yield. Each region has a model for wheat yield and determinant factors vary from region to region. Although the annual production of Bijar is higher than other areas, wheat production in the Bijar region has a higher risk than other areas.

Mostafa Mohammadi Dehcheshme, Nahid Sajadian, Ali Shojaian, Narges Gheysari,
Volume 18, Issue 48 (3-2018)
Abstract

Study how to relax and leisure from the work of citizens it is located in the field of leisure geography studies. The current study is practical in an aim and descriptive– analytical in method and practical– theoretical in nature. In this study, the first path analysis model was used in order to express logical correlations between environmental and demographics variables, on leisure geography and providing structural analysis.the results of study path analysis model shows that the impacts of the physical environment outside the home with standardized coefficients0.461 into other variables have the greatest impact and demographic variables with standard coefficients 0.025 has least impact on leisure geography of metropolis. In the following, the number of 383 questionnaires was distributed in order to study comparatively the spatial pattern leisure geography among citizen's zones 2, 4 and 7 of the city of Ahvaz that they were at different levels of enjoyment. The results of the questionnaire of citizens indicate that leisure pattern in Region2 is different from other areas; However, the pattern of citizens leisure of district4 and7 has not a significant difference together. In this context, assigning a specific type of planning is approved in order to improve the quality of community health and welfare of the citizens;; with regard to natural and human environment conditions of the city and leisure facilities available.
 


Chenoor Mohammadi, Manouchehr Farajzadeh, Yousef Ghavdel Rahimi, Abbas Ali Aliakbar Bidokhti,
Volume 18, Issue 48 (3-2018)
Abstract

 This study is aimed at estimating monthly mean air temperature (Ta) using the MODIS Land Surface Temperature (LST), Normalized Difference Vegetation Index (NDVI), latitude, altitude, slope gradient and land use data during 2001-2015. The results showed that despite some spatial similarities between annual spatial patterns of Ta and LST, their variations are significantly different, so that the Ta variation coefficient is four times the one of the LST. Our analysis indicated that while in winter latitude is the key factor in explaining the distribution of the differences LST-Ta, in other seasons the role of slope and vegetation become more prominent. After obtaining the spatial patterns of LST and Ta, we estimated Ta using regression models in spatial resolution of 0.125˚. The lowest estimation error was found in the months of November and December with a high explanatory coefficient (R2) of 70% and a standard error of 1 ° C.  On the other hand, the maximum error was obtained from May to August with R2 between 59 to 63% and a standard error of 1.6 ° C which is significant at the 0.05 level. In addition, result of evaluation of individual months showed that estimation of Ta is more accurate at the cold months of the year (November, December, January, February, and March). With considering different land uses, the highest R2 was related to waters and urban areas (96 to 99%) in warm months, and the lowest R2 was for mixed forest and grassland (between 15 and 36%) in cold months.

Dr Mohammad Hossien Saraei, Mrs Samaneh Iraji,
Volume 18, Issue 48 (3-2018)
Abstract

The management of land development in the compilation of urban development documents is a very important topic. Failure to pay attention to this necessity, and the course of physical development foreseen for urban areas, make the main goal of the development plan, which improves the quality of housing in urban areas, not being realized. The purpose of this study is to introduce a functional model for land development management in order to guide and manage the urban development flow. To this end, the Land Readjustment Plan (LR) as the selected method of land management in urban areas is introduced and it is possible to perform it in a range of Yazd city. The general research method used in this descriptive-analytic study. The data used in this article collected by the library method as well as the field survey were used and analyzed using ArcGIS software. In this regard, a proposal for the scope of the study was compiled and evaluated before and after the implementation of the plan. The calculation of the distributional index showed that the proposed scheme would give 20% of the profits to the owners in the scope of the study. The conclusion from this study shows that using the Land Readjustment Program as an economic and design tool, planning and redevelopment of undeveloped lands can be done in accordance with urban needs. This planning involves modifying the layout of parts, modifying the network of roads, supplying services and infrastructure of the facility. Thus, the field of realization of urban development plans in these areas was provided. It also provided the basis for the participation of all stakeholder groups through creating the necessary attractions for the groups influencing the implementation of the project.
 

Tayebeh Dehghani, Mohammad Saligheh, Bohloul Alijani,
Volume 18, Issue 49 (3-2018)
Abstract

In order to detect climate change, a variety of climate indicators can be used which is often considered temperature and precipitation. In order to investigate the effect of climate change on the amount of precipitation in the north coast of the Persian Gulf, it simulated the precipitable water for 2017-2050 based on the RCP4.5 model of the Hadcm3 model. The NCEP / NCAR base-station data with an arc-value of 0.125 was used to analyze the past and present precipitable water patterns and to reveal the process of this time series. Time series analysis of precipitable water was performed using two SENS tilt estimators and Man-Kendall test. The results indicated that the annual time series of rain water was increasing in the region, every year, 0.05 mm, the precipitated water increased and it tended to become more homogeneous, this increase in the significance level of 0.95. The precipitation rate in the eastern part of the region was higher than other areas. Before 1989, several fluctuations were observed in the rainy season of precipitable water, but none was statistically significant at the confidence level of 95%, but since 1989, the trend has increased significantly at a confidence level of 0.95. This spatial behavior of precipitable water can actually have occurred in response to the increase in the overall temperature of the area and can be considered as a profile of climate change in the region.
 

Ali Reza Rahimi, Ali Reza Karbalaee Doree, Mohammad Reza Karbalaee,
Volume 18, Issue 49 (3-2018)
Abstract

One of the most important parameters in maximal use of radiant energy is the proper deployment of photovoltaic. The purpose of this study was to determine the optimum setting and tilt for installing photovoltaic panel in Kashan city. For this purpose, using the Masters Gilbert physical relations and relationships, the radiation received on the surface of the panel is calculated. The results of this study indicate that the amount of radiation received on the collector's surface in the south and in different slopes, 64 percent of the time of year, is more than the radiation on the panel surface mounted in the direction of the southeast or west with different slope angles. The highest amount of radiation is in the Azimuth to the south at a gradient of 30 degrees and 40 degrees; Southwest Azimuth (30 degrees) is almost similar to the South Azimuth and only in the southeast west, in summer, glides near the verge, they receive more radiation than the south. The amount of radiation received on the surface of the panel in the direction of south east west (Azimuth 60 °) on different slopes in 87% of the year is greater than the radiation on the panel surface mounted east or west (90 ° azimuth) with different slope angles. By comparing the results, it turns out that the direction of the photovoltaic panel installation will change, as the south changes to the east or west, the intensity of radiation will decrease in the days of the year. The highest photovoltaic energy output in Kashan is in the direction to the south, and with the angle of installation of photovoltaic panel 30 degrees from the horizon line. The most suitable slope for mounting panels between 30 and 40 degrees was obtained from other slopes.

Sayyed Mohammad Hosseini,
Volume 18, Issue 49 (3-2018)
Abstract

Precipitation is a climatic elements that have temporal - spatial distribution. In this research database of Global Precipitation Climatology Centre (GPCC) with a resolution 0.5×0.5 degree for 50 year is used, that was constituted with dimensions of 12800*600. Temporal data are on the columns and pixels (spatial data) located on the rows. The results show an increasing trend in spring and fall but in summer and winter precipitation trend has been decreased. The most amount of precipitation is located in the northern parts of the Black Sea and Mediterranean Sea, Southeast Asia, southern coast of the Caspian and Central Zagros Mountains. Most of Middle East (about %95) have not trend and only in some parts of Kazakhstan, Afghanistan, Pakistan ,central Iran, and areas in lower-latitude have positive trend and some East and northwest parts of Iran and some parts of Middle East also have decreasing trend of precipitation. The highest percent of area of precipitation trend gradient is 0 to 0.5.
 

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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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. 

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

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


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.


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