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Drought Forecasting for Future Periods Using LARS-WG Model: The Case Study of Kermanshah City
2021
Heshmati, Sara | Ramezani Etedali, Hadi
The prediction of climactic changes is of great importance due to their destructive effects on aquatic, environmental, economic, and social resources. Accordingly, the purpose of this study was to predict the climactic changes of Kermanshah city using micro-scale general atmospheric circulation models accessible in LARS-WG6 (GFDL-CM3, MPI-ESM-MR, MIROC5) model in scenarios RCP4.5 and RCP8.5 for the 2020 to 2100 period based on the benchmark period of 1980-2010. In order to evaluate the data forecasted in LARS-WG model, the error rate of the observed and predicted data was addressed using R2, RMSE, MSE, and MAD criteria. The results showed that LARS-WG model had the needed capability to predict climactic data in future. In the secondary models, the MPI-ESM-MR model in scenario RCP4.5 showed a higher reliability rate compared to other secondary models evaluated in the study. Moreover, all models indicated increases in the average minimum and maximum temperature and forecasted changes in rainfall pattern in future periods in the studied area. Then, the SPI and De Martonne indices were calculated for all models. According to SPI index, all evaluated climactic models demonstrated that by the year 2100, the years with normal index would decrease while the years with dry conditions would increase. Moreover, based on De Martonne index, the GFDL model in RCP8.5 scenario estimated the climactic changes level more than other models, and predicted that dry and semi-dry years will be more than wet years. Contrarily, the MIRO model in RCP45 scenario acted more optimistically and predicted less climactic changes.
显示更多 [+] 显示较少 [-]Analysis of Spatial Form and Demographic Changes of Shiraz Metropolitan Area During the Period 1996-2016
2021
Nemati, Zahra | Dadashpoor, Hashem
The number and population of metropolitan areas have increased significantly during the last century, and in line with the increase in population, improved communications, global trends, and other significant factors, there have been many changes in the spatial development of these areas. These changes are observed in metropolitan areas of Iran during the same period, but there have been a few studies on the changes of these areas in Iran. In this study, the urban land density (U.L.D) function was used to investigate the spatial development trend in Shiraz metropolitan area from 1996-2016. The results show that the Shiraz metropolitan area has experienced a decentralized and scattered spatial form from 1996 to 2016. The pattern of changes in the region's spatial development during the years 1996-2006 and 2006-2016 shows that spatial development has become more decentralized and scattered. According to demographic analysis, the highest population density in 2006, 2011, and 2016 can be seen in the central buffer zone of Shiraz metropolis. Based on directional distribution (standard distance), the population distribution has moved to the northwest of the region. In addition, when analyzing the population distribution pattern, the Moran statistics shows that the region population is distributed in clusters. In general, the decentralized and dispersed spatial form and the formation of population clusters in the region's development process show an imbalance in the region's spatial and demographic development. Some of the significant effects of this phenomenon are urban fragmentation, social segregation, car dependency, and the destruction of agricultural lands and gardens.
显示更多 [+] 显示较少 [-]The Evaluation of Geomorphologic Landforms for the Development of Human Settlements: A Case Study of Southeast Cities of Razavi Khorasan Province
2021
Mohamadkhan, Shirin | Namjooyan, Reza | Barzkar, Mohsen | Abbasi, Mosa
The habitat development and establishment are directly related to the natural bedrock and geomorphologic complications. Due to topographical and geological conditions, the area under study has certain limitations in locating and developing human settlements. In order to reduce the hazards in the southeast of Khorasan Razavi province and modify plans for the development and establishment of human settlements, the feasibility of the area under study for residential development was investigated. After conducting library and field studies and selecting appropriate criteria, the fuzzy logic model was applied using the GIS software to identify areas for habitat development and establishment. In this study, to identify the potential areas for habitat development and establishment based on geomorphologic landforms, eleven parameters – including slope, slope direction, elevation, soil, land use, elevation, distance from fault, distance from river, distance from road, distance from settlement, and geomorphology – were used as independent variables in identifying geomorphological abilities and bottlenecks in the area. The results of zoning based on the fuzzy model showed that about 61% of the study area is located in very inappropriate and inappropriate classes, which means that geomorphological conditions in this part of the study area are unfavorable for the development and establishment of human settlements. About 14.58% of the study area has moderate conditions and about 24% of the study area shows favorable geomorphological conditions for construction activities and creation of new habitat areas. Alluvial fan units and alluvial plains are the most suitable sites for habitat development and establishment.
显示更多 [+] 显示较少 [-]Spatial Modeling and Prioritization of Potential Areas for Determining Location of Hospitals by a GIS-Based Multi-Criteria Decision Making Analyses: A Case Study of the 5th District of Tehran
2021
Zandi, Iman | Pahlavani, Parham
Hospitals are among the most essential human services whose role in the health of the citizens is very important. One of the important issues related to hospitals in developed cities is determining the optimal location for their construction. In this study, in order to select the optimal hospital location, a combination of expert opinions, GIS, and MCDM was used. For this purpose, 12 criteria were selected for the spatial modeling of the potential areas of hospital establishment, and then the weight of each criterion was calculated using the weighting method of Analytic Network Process (ANP). Then, a map of the potential areas for the hospital establishment was prepared and 11 sites in the potential areas were selected. In the next step, the weight of each criterion was determined again using Criteria Importance Through Intercriteria Correlation (CRITIC) method. Then, by the integration of two weighting methods, i.e., ANP and CRITIC, with two MCDM methods, i.e., EDAS and VIKOR, these sites were ranked. The results of spatial modeling showed that the western half of the district is more suitable for the construction of a new hospital than the other areas. According to the results of the ANP, the distance from hospitals, and according to the results of the CRITIC, the seismic vulnerability were the most important criterions in determining the optimal hospital location. Based on the ranking results coming from CRITIC-EDAS, CRITIC-VIKOR, and ANP-EDAS, the site No. 1, and according to the ranking results of the ANP-VIKOR, the site No. 8 have been the most suitable places for the construction of a new hospital. In the light of the results of the site evaluations by experts, CRITIC-EDAS and CRITIC-VIKOR methods are more accurate for hospital location selection.
显示更多 [+] 显示较少 [-]An Analysis of the Continuity and Cohesion of Urban Ecologic Network Through a Graph Theory Model
2021
Gorbani, Rasol | Rostaei, Shahrivar | Karbasi, Pooran
Nowadays, problems related to the environment, society, and identity of cities derives from their expansion and the increasing penetration of natural space by human-made space. Green spaces are deemed not only as a green patch at the disposal of the masses, but also as a factor for the improvement of citizens’ life. On the other hand, the destruction and removal of homogeneity and continuity of natural infrastructures and green networks threatens the biological diversity and brings about limitations for development. Therefore, continuity of the urban green spaces provides habitats and corridors that help the preservation of biological diversity. To develop green space networks, increase continuity, and revive biological diversity, urban planners have used landscape ecology principles. Adopting a descriptive-analytical method and review of the scientific resources, this study investigated landscape connections and their importance for the preservation of biological diversity. Maragheh city green space network was modeled in GIS according to Graph theory. Then, the ecologic continuity analysis was carried out through Conefor software along with Integral Continuity (IIC) measure and point picking algorithm, and the urban green patches were valuated. At the end, the potential corridors in Maragheh city were identified using the least cost method, which then developed and improved the green space networks. The results of this study reveal that the majority of the built corridors are located around the city like a green belt. The main reason for this is the positioning of the main habitats in the city outskirts. Moreover, the green space network developed based on Graph theory made the complex landscape simpler and more organized, and helped with the identification of green space and the guidance of urban planning for the protection of biological diversity.
显示更多 [+] 显示较少 [-]The Feasibility Study of Areas Appropriate to Recreational-Sports Trekking in Dorud City
2021
Dehghani Firozabad, Leila | Mirsanjari, Mir Mehrdad | Ildoromi, Alireza | Abedian, Sahar
The identification of areas appropriate for the sustainable growth and development of touristic activities is among the main topics of tourism planning. With its positioning between a mountainous area and a plain, Dorud city enjoys topographic diversity and numerous natural attractions that need proper management and appropriate planning in order to attain the objectives of the sustainable development of tourism. Aiming at the examination of the potential of this area for recreational-sport trekking ecotourism, the study at hand set out to assess the ecologic power of this area using multi-criteria evaluation method. This study was applied-developmental in terms of purpose, and descriptive-analytical in terms of research framework. Since the identification and evaluation of tourism potentials is a multi-criteria decision-making question, five main criteria groups – including physical, ecologic, infrastructural-bodily, safety, and economic-social criteria groups – and 25 secondary criteria for the recreational-sport trekking tourism were developed. The weighted linear combination was used to integrate the criteria. Then, the final map for ecotourism activity in the region was drawn in three spaces with low, mid, and high capability. The results of the final desirability map showed that 6.9 percent of the area has high potential for recreational-sport trekking. Moreover, the results of TOPSIS revealed that Qarun and Oshtorankuh mountains are the first and second top ranking mountains for recreational-sport trekking, respectively. Overall, the results of this study demonstrate the appropriate areas for recreational-sport trekking, which can function as a guide for tourists, managers, and planners to make decisions and administer developmental policies in the light of environmental and socioeconomic approaches and considerations.
显示更多 [+] 显示较少 [-]The Description and Explanation of the Logistics Spatial Structure Changes and the Factors Effective on Them in Tehran Metropolitan Region
2021
Sadati, Alireza | Dadashpoor, Hashem
The purpose of this study was to investigate and analyze the logistics spatial structure changes and to explain the objective factors affecting it in the Tehran metropolitan region during the period 1986-2011. The research method was descriptive-analytical, and in order to achieve the objectives of the research, three analytical methods – including indicators of number changes, growth rate, as well as the relative rate of changes in population density – employed in the logistics sector of each geographical area were used. On the other hand, analytical methods for measuring the degree of spatial concentration such as Gini coefficient and spatial autocorrelation as well as multiple regression analysis were used to estimate the correlation of effective factors with the spatial distribution of the employees working in the logistics sector (as the independent variable). The results of the analysis show that from 1986 to 2011, the spatial pattern of the logistics geographical distribution in the Tehran metropolitan region was centralized, consisting of the logistics cluster of Tehran metropolis. That is to say, tracking the process of spatial changes showed the decentralization of the population working in the logistics sector of Tehran metropolis and the concentration of this working population in the western and southwestern geographical areas surrounding the metropolis. From 1986 to 1996, among the objective factors affecting the logistics spatial patterns of metropolitan areas, the spatial distribution of the population working in the logistics sector had a higher correlation with the spatial distribution of population and labor force. That is to say, the higher the number and density of population and labor force in the geographical area, the higher the population working in the logistics sector. However, from 2006 to 2011, the spatial distribution of the population working in the logistics sector had a higher correlation with the spatial distribution of the population and the literacy rate.
显示更多 [+] 显示较少 [-]An Analysis of the Role of Local Management in Strengthening the Islamic Republic of Iran, With an Emphasis on the Role of City Councils
2021
Seddiq, Mir Ebrahim | Shirzadi, Reza | Rashedi, Asadollah
Up until now, Islamic Republic of Iran – rising from among people and adopting a religious and divine discourse – has provided a unique model of the administration of people’s affairs in various dimensions through the creation and enhancement of institutions and structures appropriate to its political system. Accordingly, the consideration of ideals in the form of structures, institutions, and approaches is an issue that has a unique role in strengthening the internal structure of this political system. In this article, using the descriptive-analytical method and collecting data through document analysis, library research, and survey methods, city council – as an institution rising from the public vote and a phenomenon similar to local parliament – are defined as the dependent variable. Moreover, in line with the identification of the dimensions and history of these councils, the position of council in Islamic thought is discussed. According to the obtained results, it can be maintained that councils’ importance has four important and effective aspects, namely participation in, distribution of, penetration in, and formation of the identity of power and internal structure strength. To this end, they play roles in four directions, namely strengthening the internal structure cohesion through providing identity to individuals’ roles, enhancing the influence of the Islamic political system in various layers of people and society, fulfilling the maximum participation of people and the role of people in governance, and the just distribution of resources based on reality and the local and national desires. It was found that councils have had greater effectiveness in the fulfillment of maximum participation and involvement of people in governance compared to other directions.
显示更多 [+] 显示较少 [-]Purposeful Regeneration Using Development-Inducing Projects Approach via the Integration of COPRAS Algorithms and CCDS: The Case Study of Imam Street and Kohne Dezh Neighborhood, Dar- ol-Marhame, Semnan
2021
Ziari, Keramatollah | Ehsanifard, Aliasghar
The rundown urban buildings and old neighborhoods with ancient, valuable constructions are like the beating heart of the cities. Nonetheless, they have lost their social, cultural, and economic functions. Urban regeneration is an approach that intends to revive and modernize these rundown buildings and traditional neighborhoods. The purposeful effort to reinject life into these areas and provide conditions for the public presence and participation in its practical process are among the valuable objectives of this approach. The main question of this study revolves around the way to choose intelligently and purposefully the type of regeneration, the intelligent and purposeful selection of the development-inducing uses and project, and the examination of the purposeful effects of the urban development-inducing projects on the process of urban regeneration in Semnan neighborhoods intended for regeneration. This study adopted a descriptive-analytical research method. In order to rate and prioritize regeneration types, land uses, and development-inducing projects in the process of neighborhood regeneration, COPRAS model was used, while CCDS was used to weigh the criteria. In the document analysis part, the main documents in the urban regeneration and development-inducing arenas were examined. Moreover, in the field study section, three committees – comprised of the experts of urbanism and urban regeneration, urban designing, and social and architectural studies – were formed and tens of meetings with the managers and officials of Semnan districts along with urbanism representatives were held during which the development-inducing regeneration capacities in these neighborhoods were discussed and investigated. The results of COPRAS test showed that the development-inducing regeneration with touristic and recreational uses along with the opportunity- and value-making factors of tourist attraction as well as the increase in the international ranking of the city through the purposeful, development-inducing plan of designing and constructing sidewalks and making the central part of the neighborhood walking-oriented, and the development-inducing project of the walking zone of Imam street with the score of 0.739 from the top factor of the purposeful regeneration of Semnan, which needs a serious resolution and precise planning. The first rank in the purposeful regeneration of Dar al-Marhama neighborhood in Semnan is the development-inducing regeneration with the purposeful touristic and recreational use that will increase the position of the city in the competitive and macro environments of Iran and international space. Attracting Iranian and international tourists, changing the nature of the rundown buildings, and preparing the mental state of the citizen about tourism development, this regeneration plan will increase the international status of the Semnan city at the international level and will create urban opportunities and values.
显示更多 [+] 显示较少 [-]The Examination of the Landscape Metrics Changes Using Urban-Rural Gradiant Analysis Method: The Case Study of Tehran Metropolis
2021
Radyn Majd, Golazin | Jozi, Seyed Ali | Hejazi, Rokhshad | Amiri, Mohammad Javad | Ghaffarzadeh, Hamidreza
The detection of urban landscape changes in urban areas is of utmost importance for the maintenance of the safety of environment and the promotion of sustainable development. To this end, the consideration of the spatial metrics capabilities to describe the landscape structure can be a valuable move to identify the growth models in metropolises. The purpose of this study was to provide the urban-rural gradient analysis of the landscape metrics in Tehran metropolis in the year 2018 as well as the analysis of their change trend in order to investigate the spatial-chronological changes in the landscape. In order to analyze the metrics, the moving window method was used at landscape and class levels. To this end, Landsat 8 satellite images were used, and the landcover was divided into human-made, open, vegetation, and water lands in a supervised manner. As with the gradient analysis, transects with 4km*4km dimensions at four directions – namely center-northeast, center-southeast, center-northwest, and center-southwest were directed from District 12 of Tehran Municipality in GIS 10.2 software. The results showed that at the landscape level, the closer we go to the business center of Tehran Metropolis, the number and density of patches increase, while the closer we go to rural areas the average index of landscape shape has relatively uniform changes. At the class level, the more distant we get from the business center of Tehran metropolis, the percentage of human-made patches and open lands increases and that of the vegetation patches decreases. Then, it might be concluded that urban development has brought about an increase in the density of patches in landscape, such that in the central transect, the continuity of landscape is reduced, and the fragmentation of the structural elements of landscape is increased. The land use changes have led to the expansion of the city toward the country and have negatively affected the vegetation and water resources.
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