Showing 46 results for Gis
Maryam Aghaie, Siamak Dokhani, Ebrahim Omidvar,
Volume 24, Issue 74 (9-2024)
Abstract
Rain water harvesting is an appropriate option for storing surface runoff for subsequent uses during periods with limited access to water. The most important step in the application of rainwater harvesting systems (RWH) is the site selection suitable areas. Therefore, by identifying suitable sites for this purpose, time and cost will be saved . In this research, multivariate regression model and GIS were used to site selection in situ (RWH) in Tajare watershed. For this purpose, layers such as crown cover, litter, rock and stones, soil, curve number, rainfall, slope and depth of field as independent variable and infiltration were considered as the dependent variable. Then, according to the maps, their values were calculated in average for each of the 27 sub-basins. Also, to investigate the relationship between these variables and weighting, each of the effective layers of multi-variable regression was used by the stepwise method The results showed that the linear multivariate regression model with an explanation coefficient of 0.993 was able to estimate the penetration factor values well In terms of grade of importance, the curve number variables with a coefficient of -2.433, depth of soil with a coefficient of 0.3488, and rubble and gravel percent with a coefficient of 0.057, were the most important, and other factors were not significant. Comparison of the map from the site selection of multivariate regression in this research with some recommended criteria of various research studies showed that the predicted classes with good in the central parts of the basin and very good in the upstream areas of the basin which in the eastern and southeastern part of the basin fit have a good overlap with the recommended areas with these criteria.
Mr Shokrollah Kiani, Mr Ahmad Mazidi, Mr Seyed Zein Al-Abedin Hosseini,
Volume 24, Issue 74 (9-2024)
Abstract
Subsidence is an environmental phenomenon caused by the gradual subsidence or sudden subsidence of the earthchr('39')s surface. The phenomenon of subsidence in residential, industrial and agricultural areas can cause catastrophic damage. In most parts of Iran, there is a high correlation between land subsidence and the decrease of groundwater level and consequently the density of soil layers. In this study, using two time series of radar images with artificial apertures from Sentinel sensors belonging to 2014 and 2019, the amount of subsidence in Damaneh plain (Frieden city) was calculated. Wells were studied in the period 2014 to 2019, the results of the study of the correlation between land subsidence with changes in groundwater level at the level of 95% was significant. In the continuation of the research, using the logistic regression model, the subsidence trend in the study area was predicted and a subsidence probability map was prepared and created as a dependent variable for the logistic regression model. The independent variables used included altitude, slope, slope direction, geology, distance from the road, distance from the river, land use, distance from the village, groundwater level, piezometric wells. The output of the model is subsidence risk zoning map which was created in five classes. The accuracy and validation of the logistic regression model was evaluated using the system performance characteristic curve and the accuracy (0.89) was obtained. The good accuracy of the logistic regression model in producing the probability map Subsidence is in the study area. In the output of the model, it was found that the area of 1980 hectares, equivalent to 7.9%, has a very severe subsidence that has put the situation in a dangerous situation and the need for control and management to reduce this destructive effect.
Reza Kheyroddin, Nazanin Mostafavi Esfahani,
Volume 24, Issue 75 (12-2024)
Abstract
Landuse planning goals as the main core of urban planning are classified and studied from different aspects. The inclusion of additional value of surplus funds in the city can highlight capital funding. Following this, changes in urban land demand as the spatial changes of activities and functions occur.The commercialization of residential areas and the tendency of residential landuse changes are the disadvantages of these changes,which constitute a major part of residential neighborhoods of Tehran metropolis ,especially the northern neighborhoods of the city. The main structure of Nasr neighborhood in the 2th district of Tehran is based on Gisha street. The most important issue is multiplicity of commercial land uses in the Gisha street. According to the observations there is a bank in every 45metres of the street , while the performance radius of bank activities is defined in the region scale. It is argued that land price growth, financial and speculative justifications of these changes can cause pressure on the environment.Therefore, according to the above mentioned factors,the main objective of this study is identifing the factors affecting landuse changes in the Gisha street.
The research method in this study is documentary , local survey as well as the use of factor analysis in order to determine factors affecting landuse changes.By using this method, accessibility,landeconomics and activity distribution and neighborhood structure were considered as three factors affecting land use changes in the Gisha street .
Finally, in order to plan to control the speculative consequences of these changes , the analysis of external and internal factors with regard to indicators in questionnaire, SWOT table and finally defensive strategy to offer strategies and policies was adopted these strategies were presented in two categories: sustainable management of income sources of urban management and control of changes in land use changes.
Mohammad Baaghideh, Motahhareh Zargari,
Volume 25, Issue 76 (3-2025)
Abstract
The performance of broiler chickens is directly influenced by temperature changes and the occurrence of heat stress, whether it is cold or hot. The present study aims to assess the cooling and heating degree days in different stages of broiler chicken production in Khorasan Razavi province. To achieve this objective, daily average temperature data were collected from 13 synoptic stations during the statistical period of 1988-2018. Cooling and heating degree days were calculated for each week of production using specific thresholds, and their spatial distribution was analyzed. Furthermore, the relationship between cooling and heating degree days and geographical features was evaluated. The findings indicate a decrease in cooling degree days and an increase in heating degree days as latitude increases. The northern and western regions of the province exhibited a greater need for heating throughout all stages of broiler chicken production, whereas the eastern and southern regions had higher cooling requirements at different production stages. Overall, the northeastern, southern, and western marginal areas of the province, including Khaf, Gonabad, Kashmar, Sarakhs, and Sabzevar, exhibited the lowest cooling and heating needs during the 6-week period of broiler chicken production, making them suitable climates for this economic activity.
Seyed Komeil Salehi, Ms Habibeh Nabizadeh, D.r Amineh Anjem Shoa,
Volume 25, Issue 77 (6-2025)
Abstract
The objective of this research is to investigate the factors that enhance the attractiveness of tourism destinations in Tehran. This study is applied in nature and employs a descriptive-analytical methodology. The data collection methods include the use of questionnaires and interviews. The statistical population comprises tourism experts and specialists, and through the application of Cochran's formula and simple random sampling, a sample of 210 tourism experts was selected. Data analysis was performed utilizing descriptive statistics and logistic regression tests. The findings of the research reveal that, out of the 210 tourism professionals in Tehran, 91 individuals, representing 43.3%, perceived the attractiveness of Tehran's tourism destinations to be at a high level; 29% assessed it as moderate; and only 27% regarded it as low. Furthermore, the results concerning the factors influencing the enhancement of attractiveness in alignment with tourism development indicate that, among the four factors considered, the most significant were: 1) innovative business opportunities, with an impact coefficient of 0.613; 2) the city's natural, cultural, and historical assets, with an impact coefficient of 0.577; 3) the development of tourism infrastructure, with an impact coefficient of 0.497; and 4) urban development, with an impact coefficient of 0.473.
Ph.d Elnaz Piroozi, Ph.d Sayyad Asghari Saraskanrood, Ph.d Batool Zeinali,
Volume 26, Issue 80 (3-2026)
Abstract
Landslides are among the most common and destructive natural hazards that change the shape of the earth's surface, and reviewing the damages caused by landslides, the need to investigate the factors influencing the occurrence of this phenomenon and predict its occurrence. proves that Khalkhal City, due to its special geological, climatic, and geomorphological characteristics and human activities, has been affected by the risk of landslides for a long time. Therefore, considering the importance of the issue; The purpose of this research is to produce a landslide risk map in this city. In this regard, first, the distribution map of landslides and influencing variables, including; DEM, slope, aspect, land use, lithology, distance from fault, distance from river, distance from road, and rainfall were provided. Next, after the fuzzy membership and determining the weight values of each factor using the CRITIC method, the landslide susceptibility map was prepared using the MARCOS multi-criteria decision-making method. The results of the study showed, respectively; that The factors of slope, land use, and lithology with weight coefficients of 0.148, 0.139, and 0.132 have the greatest influence on the occurrence of landslides in the region. According to the results of the research, respectively; 707.14 and 512.87 square kilometers of the area of the city are in high-risk and very high-risk categories, and these areas are areas that need management work and the implementation of protection projects. Also, considering the use of the ROC curve method the area under the curve (0.89), and the correlation of 0.83% between the final map obtained from the research and the distribution of sliding surfaces, the accuracy of the MARCOS method in identifying and zoning prone areas The risk of landslides in Khalkhal city is great.
