Geographical Research

In this research، the applicability of geographic information system (GIS) and remote sensing (RS) techniques was tested to assess soil erosion risk with the ICONA erosion model. This study was carried out in the Tange Bostanak area because of its variety of diverse landforms، land uses and land covers. The erosion risk assessment phase of this model consists of seven steps that mainly use slope، geology; land use and land cover information. A potential erosion risk map (step 3) was obtained from the slope (step 1) and kissing layers (step 2) generated using a digital elevation model (DEM) and digital geological maps. As a result of this process، the distribution of the erosion risk classes was 28/6% (very low)، 36/7%(low)، 26/7%(medium)، 4/8%(high)، and3/2% (extreme). Land use (step 4) and land cover (step 5) layers derived from Landsat TM image data classification were combined to produce the soil protection map (step 6). During the final predictive phase، soil erodible and soil protection layers were combined to generate the ICONA soil erosion status map (step 7). The final map showed that 8% of the area had high and very high erosive status. These areas especially included hilly and mountainous areas، and excluded the forested parts. The rest of the study area had lower (very low، low and appreciable) erosion status. The present study shows that GIS and RS techniques have an important role to play in soil erosion risk studies

This study is a descriptive - survey and objective evaluation analysis of creation causes on informal settlement Shadgholi-Khan town of Qom city. answer Questionnaire by 200 protector of household in Shadgholi-Khan Tow، economic، social and Physical variables affective creation of informal settlements in the Shadgholi-Khan its spatial and local effects are investigated. Research findings show that ten factors influence as important factors creation of Shadgholi-Khan، and using regression techniques factor affecting each of these factors and identified using Path Analysis model of how these factors influence has been analyzed. According results of Path Analysis model، it became clear that in creation of Shadgholi-Khan two factors were before the migration، including; initial ownership، migration reasons، immigration or not immigration and before job and after factors of migration included; current job، document ownership، residence reasons، creation license house، income and years of migration is the highest influence. All coefficients of elements and the effects of various independent variables affect each other and separating them، it was shown that the rate of immigration before 56.6 percent and the rate of immigration after 43.4 percent were effective in creation of Shadgholi-Khan. Now if planners and policy makers seek to solve problems arising from informal settlements in cities، should its roots search in the factors influencing before migration and villages، and after solve current root، do solve problems of informal settlement.

Aims: Improving spatial access to public services is one of the effective tasks of urban management to develop urban living standards which provides justly facilitating and benefiting of received services for citizens. The aim of this study was to apply the dynamic locating of public services centers in long-term urban management planning.
Methodology: In this applied descriptive research, at first the studied conditions were defined in terms of decision variables, parameters, objective function and limitations by reviewing the research background and experts' opinions. Then the data were collected using databases and expert opinions and finally, mathematical modeling of dynamic locating was performed to maximize the desirability of selecting the counters offices of Civil Registration in Mashhad and the model was solved by the CPLEX solver with the branch and cut algorithm.
Findings: While identifying the indicators of desirability of candidate points, the location of offices in urban areas, the time of reopening and closing, and relevant time period were determined. Activity timing and locating offices, covering 80% of the population and suitable geographical distribution with 39 offices were performed, and optimal value of the objective function was achieved in terms of the indicators considered by the stakeholders and maximum desirability.
Conclusion: Due to the low performance of static models, demographic changes and demand in the field of urban management, a dynamic model was used to solve this problem to provide a more accurate picture of the time of office creation in each area, the ability to select offices with appropriate reliability for activity. And allocating the customers of every region per period to the best location in terms of providing stakeholder indicators.

Aims: The development of large-scale construction projects has transformed the shape of cities towards specific objectives and based on economic and political perspectives that dominate policy-making and planning in cities. The purpose of the research was to study and analyze the spatiality of Mashhad construction mega-projects and to explain the constructive forces and dynamisms of these projects in the framework of the political economy of space approach.
Methodology: The present descriptive-analytical research was conducted in 2020 in Mashhad. Constructive dynamisms of 164 large-scale urban projects were identified and classified based on theoretical perspectives and through the Delphi technique based on the opinions of 50 elites and subject matter experts, and the model was presented. To test the five-factor model using structural equation modeling, the relationships between variables and generalization of results were discussed. Data were analyzed using SPSS26 and smartpls 3 software and confirmatory factor analysis test.
Findings: Based on the results of confirmatory factor analysis, the model had an acceptable fit with the data. At the transnational level, the Policy-Management and Programs factor with a factor-load (0.745), at the national-regional level, the institutional-organizational factor with a factor-load (0.802) and at the local level, the economic-political factor with a factor-load (0.772). They are important in the first place. The model had validity and reliability.
Conclusion: The results of research analysis based on the philosophy of creating construction mega-projects in Mashhad within the framework of five identified and consolidated factors indicate the role of drivers of policy dynamisms at the transnational level, institutional-organizational forces at the national-regional level and economic and political forces at the local level.

Aims: Urban development plans try to restore dynamism and vitality to urban contexts, but the lack of existing structure and modeling of previous plans has made the definition of sustainable urban form a challenge for urban planners. The purpose of this article was to explain the coherent form of Shiraz based on the concept of connectivity. 
Methodology: This descriptive-analytical research was conducted by documentary and field method in 2021. This study was conducted in Shiraz and the sample size was urban and street blocks and functional zones of 11 districts of this city.
Findings: The interconnected centers of the city geometrically and functionally affect each other as long as all the effects occur between the centers in a single area. Therefore, before applying changes in the physical form of each area of Shiraz, its consequences should be considered in the affected area. These consequences are due to the position of the position in relation to the priority of influencing the influence of the boundary number of each block, influence in complex network centers and interconnected centers, irregular structure, control and promotion of construction, population and the extent of various economic and social indicators, culturally, and physically examined.
Conclusion: In the process of urban planning, changes in each region should not be considered as an independent region and the pattern of interoperability in urban development planning and management should be considered for regular organization and their effects in order to achieve Use coherence in form.