Urban Design
Azin Hajiahmadi Hamedani; h m; l j
Abstract
Evaluation of every environment’s image is not just the result of impressions made by its external attributes on the mind of the observer. It is, however, created by the imagination of the observer. A city is lodged by a wide variety of people whose evaluation of the images they form in their mind ...
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Evaluation of every environment’s image is not just the result of impressions made by its external attributes on the mind of the observer. It is, however, created by the imagination of the observer. A city is lodged by a wide variety of people whose evaluation of the images they form in their mind is critical. The desirability of urban environments for various social strata, especially for women, depends on the relationship between human beings and the environment as well as their priorities and preferences. The distinctive characteristics of women in terms of feelings, sensation and evaluation of the environment should not be preferred over one anonther. To achieve a realistic and true viewpoint, it is impossible to ignore the interests and preferences of the citizens in relation to their living place. Since the relationship between an individual and their surrounding environment is formed in various levels such as the individual (e.g. feeling, perception, values, mental experiences, etc.) and social level (e.g. various social groups or the ones which are similar in terms of age and sex), it is better to examine the characteristics of various groups and social strata on the same level. The interpretations and mental images and meanings formed by women are unique depending on their values, priorities and experiences. There are some factors affecting the recognition of pleasantness attributes in urban space in women’s view, inducing what attracts women’s attention in the environments, how they are memorized, their mental image and their evaluation of the percieved space and the environmental preferences in selecting a desirable location. This article examines the factors affecting women mental image in order to allow the creation of a favorable environment from the perspective of this social group. It evaluates the preferences of their space. What is important is to identify and assess the main criteria for women in determining the optimum location with respect to the meaning derived from evaluated images. The aim of this research was to improve desirability of the environment from the perspective of women as well as their right to choose and evaluate the image of public spaces of Tehran. The research method is based on the techniques developed by Jack L. Nasar. In Nasar’s study, a phenomenological hermeneutic approach is used to describe the connotations and emotions image representation of women in the experience of urban spaces desirable / undesirable and nature of development of the city of Tehran. For this purpose, 15 in-depth interviews were conducted through purposive sampling. Interviews were recorded and the obtained data was written in the form of tables. Repeatability analysis was performed on the data. The results indicate that the optimal site selected through women’s mental image of highly desirable locations is associated with the concepts of freedom, justice, place dignity, socio-cultural prestige, historical identity, beauty, being stylish and full of details, quiet and cozy, vast but with privacy, green, happy mood and health.
Urban Planning
Abstract
Land-use and development density decisions have always been amongst the most controversial issues in urban planning. Various approaches have been proposed to deal with these decisions. However, these approaches have been mainly theoretical rather than practical. Transit Oriented Development (TOD) is ...
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Land-use and development density decisions have always been amongst the most controversial issues in urban planning. Various approaches have been proposed to deal with these decisions. However, these approaches have been mainly theoretical rather than practical. Transit Oriented Development (TOD) is amongst the most recent approaches to urban planning and, consequently, land-use and development density decision-making. TOD has been defined as “a compact, mixed-use, community, centered around a transit station that, by design, invites residents, workers and shoppers to drive their cars less and ride mass transit more.” This paper aims at proposing a mathematical model for land-use and development density decisions based on the principles of TOD. TOD is generally considered to have three dimensions: design, density and diversity. Design needs to be prepared according to specific conditions and circumstances of each particular station area. On the other hand, planning for development density and diversity needs to be developed from a holistic viewpoint, regarding different macro-scale objectives and constraints. In this paper, the problem of development density and diversity optimization based on the principles of TOD is modeled as a mathematical programming problem with multiple objectives. The first objective is to maximize development density in station areas, and the second objective is to minimize the difference between each station’s ratio of job-housing balance and its ideal value (ratio of employed people to the number of residential units) in each TOD area. Several constraints related to the objectives of Tehran master plan have also been incorporated into the model. The resultant nonlinear model was transformed into a Multiple Objective Linear Programming (MOLP) problem using simple mathematical transformations. Then, using AUGMented Epsilon CONstraint (AUGMECON) technique, it was transformed into a single objective Mixed Integer Linear Programming (MILP) problem. Finally, the model was applied to a real case study in the 12th District of Tehran metropolitan area and the results were thoroughly analyzed. Statistical analysis of the results shows that the elasticity of diversity to development density is -1.017. In other words, 1% improvement in diversity leads to a 1.017% decrease in the development density index. Optimal trade-off between these objectives depends on (1) their relative impact on car ownership ratio, vehicle-miles travelled and similar criteria, (2) particular micro-scale issues of each station area as well as the goals and strategies of the municipality for each station area. Previous studies show that land-use diversity has a higher impact on the aforementioned criteria than development density. However, these results depend highly on urban development, urban transportation patterns and the behaviour of citizens. Hence, proper decision-making needs a separate study on the aforementioned impacts on travel behaviour of the citizens in the context of Tehran. Furthermore, the Pareto solutions of the proposed model provide a set of alternative development policies and enable the policy-makers to select among them based on their specific conditions and limitations. The proposed model results can be applied to future urban development plans.
khashyar kashanijou; hamed mohammadi; naeime salehi
Abstract
Industrial revolution, urban growth and population increase have greatly affected the area of cities and have caused a staggering increase in the number of automobiles and streets built to facilitate automobile movement. One of the most important problems in urban streets is pedestrian-vehicle ...
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Industrial revolution, urban growth and population increase have greatly affected the area of cities and have caused a staggering increase in the number of automobiles and streets built to facilitate automobile movement. One of the most important problems in urban streets is pedestrian-vehicle interaction at crossings which is a substantial concern for citizens. Installing footbridges has been supported by related organizations in Iran to solve this problem and increase walkability of the streets. In brief, walkability is the attraction level of places for pedestrians’ presence. Based on the opinion of many urban authorities, footbridge is one of the mobility facilities in crossing the streets. Bridges were used to cross the barriers since a long time ago. However, they were built for avoiding automobiles on the streets and their design were upgraded since about half a century ago. This applied research seeks to comparatively evaluate footbridges and pedestrian crossing in relation to walkability. For this purpose, Karim Khan-e-Zand Street in District 6 of Tehran, between Valiasr Square and Haft-e-Tir Square, was selected as the case study. It is a mechanized footbridge at the intersection with Hafez Street. An ordinary (non-mechanized) footbridge has been installed on it at the intersection of Kheradmand Street. The article is based on the analytical-descriptive method. The Analytic Network Process (ANP) is used to evaluate the findings. After studying the theoretical concepts of research through a documentary-library method, appropriate criteria for walkability assessment are weighted by the Delphi method and field data is collected through survey method using questionnaires distributed among 150 citizens. The obtained data was analyzed by Super Decision software package. Three options were considered for citizens to evaluate footbridges in terms of walkability of Karimkhan-e-Zand Street in Tehran: using non-mechanized footbridges, mechanized footbridges and pedestrian crossing. The findings show that security and safety, mobility, accessibility, and physical conditions are respectively more important than other criteria in selecting footbridges for crossing the street. Furthermore, the least important criteria are attraction and comfort of the path and its maintenance quality, respectively. Among the sub-indicators related to security and safety of paths, crime-related security and presence of others were selected as the most effective ones. The length of path is the most important factor while the slope and topography are the least important factors related to the physical condition of the path. Path lighting in night was selected as the most important sub-indicator related to facilities. Also, path continuity and ease of mobility can be referred to as the most important factors among sub-indicators of movement and accessibility. Finally, with regard to the walkability of streets, despite the opinion of urban managers, level crossing with a score of A=0.36 is more favorable than footbridges, and mechanized footbridge with a score of B=0.33 is more desirable than non-mechanized footbridges with a score of C=0.30. Therefore, it seems that a fundamental review is required in the current trend of development of footbridges in Iran.
Urban Ecology
Salahaldin Shoshtari; Mahmoud Ghalehnoee; Victoria Ezzatian; Aida Maleki; Mostafa Paknejad; raofeh rahpou
Abstract
The urban heat island phenomenon is one of the challenges with which most metropolises have been struggling due to unplanned city expansions. Multiple factors have led to the emergence and escalation of this phenomenon, which can be classified into three main categories: the macro-climate of the region, ...
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The urban heat island phenomenon is one of the challenges with which most metropolises have been struggling due to unplanned city expansions. Multiple factors have led to the emergence and escalation of this phenomenon, which can be classified into three main categories: the macro-climate of the region, materials used at urban fabric and urban texture. Various suggestions have been given by experts in this area to reduce the severity of this phenomenon and improve the urban microclimate. However, as the phenomenon is different in each city or metropolitan area, various location-specific solutions will be offered to reduce the factors contributing to the phenomenon. The study uses satellite data, including images of the Landsat satellite on July 18, 2015, as well as the overnight satellite images of Modis and the GIS, along with land data from the metropolitan weather stations closest to the selected simulation area where thermal islands were examined. In this regard, the extent of the impact of different uses on the formation and severity of thermal islands in Isfahan was investigated. Based on the findings, applicable suggestions in the field of urban activity are made with an emphasis on the green space. In this paper, on the city level, the main green spaces including green spaces of urban streets and different types of urban parks were examined with regard to their geographical location in terms of the three categories of surface temperature (approximate 24-35°C, 35-40°C, and 40-51°C) and the applied map of each of these categories were developed. Accordingly, at the city level, the temperature in 10% of urban green spaces was above the normal, the temperature in 15% of urban green spaces was in the normal range, and the temperature in 3% of these spaces was lower than the nornal range. The Abbas Abad area was studied in terms of urban usage through a simulation of the effect of green spaces, especially green spaces on the boundaries of the roads on the urban microclimate. This area is one of the areas with the most abundant, old green space in the city. In this regard, an urban green space with old trees was selected in the historical fabric of Isfahan and was modeled using Envi-Met. The simulation results for summer 2015 indicate that, despite the close proximity of the three selected points, about 1°C of difference is seen in the temperature of the three spots. The proximity of the water bodies, and green spaces in particular, is one of the main factors. Additionally, the ground data follows the pattern of simulations points as well. Therefore, different scenarios are proposed for the presence of green spaces and evaluated through simulation. The results of this paper show that small green spaces, if designed based on scientific principles, can have a good effect on the thermal effects of heat islands on the small scale. Also, because of the large scale of urban areas, the combined methods proposed in this study can lead to the application of measures to reduce the negative effects of heat islands for urban management.
Urban Design
Yones Changalvaiee; Mostafa Behzadfar; Mahmud Mohhamadi; Zahra Sadat Saeideh Zarabadid
Abstract
As an interface between humans and their peripheral environment, urban form is the embodiment of formative and transformative flows of the built form. Energy flows of urban form production, operation and maintenance lead to the generation and transformation of built form which is the transmitter of information ...
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As an interface between humans and their peripheral environment, urban form is the embodiment of formative and transformative flows of the built form. Energy flows of urban form production, operation and maintenance lead to the generation and transformation of built form which is the transmitter of information flows, such as visual and perceptual flows, between humans as receptor and the built environment. On this basis, continuous and integrated interactions between humans and the living environment is considered as energy operational flows of environmental comfort (heating and cooling energy demand) and informational flows of perception, cognition and evaluation of the built form (focusing on visual interaction) which are the two generic flows of built form in relation with humans. These relations and interconnections between energy and information flows are excavated based on the Eco Efficient Urban Form (EEUF) model. The present research aims to explore the relationship between these two flows and the built form based on two distinct states of occlusivity factor: distribution of built elements in vertical plane (Adolphe occlusivity factor for operational energy flows), and Benedikt occlusivity factor for visual information flows which demonstrates the interconnections between the horizontal built elements perimeter map and visual sight flows. The analytical content of the study was chosen from the morphological aspects of Isfahan in the form of ten morphological types presenting general morphological trends of Isfahan. With regard to these, results indicate that there is an inverse correlation between the two states of occlusivity: occlusivity in vertical planes for energy performances and occlusivity in horizontal planes for sustainable visual information flows between built form and humans. The results reveal that the fabrics with organic morphological aspects and structure have a higher value in terms of energy performance occlusivisty factor, especially effective for decreasing heating energy demand in cold seasons, and a lower value in terms of isovist occlusivity factor, indicating higher value of isovist compactness leading to coherency in visual information flows. Hence, the results indicate that the integration between two generic flows of sustainable urban form is demonstrable for old tissues with old organic morphological patterns. The main contribution of the study is to confirm the relationship and interconnection between generic flows of energy and information as the key content of EEUF model.The research is focused on the operational mode of energy flows (indoor energy demand) and the visual interactions of information flows. Finally, future research should therefore concentrate on the investigation of the integrity between perceptional aspects of urban form and outdoor environmental comfort as the main characteristics of urban form environmental performance in the form of EEUF model. It is worth to mention that the study is mostly focused on the environmental performance and morphological configuration in hot and arid climate. Therefore, other effective parameters such as structures, visual proportion of vertical facades, aesthetic aspects, meaning of place, environmental preferences, sense of place, etc. necessitate further investigations in the future. Reanalysis of the study model according to the new types of morphological units and other climates as well as addressing perceptional aspects can provide valuable results for developing sustainable urban form frameworks.
Urban Planning
Farshad Noorian; seyed sajad abdullahpur Razkenari; reza ghazi
Abstract
Mashhad megalopolis has experienced a rapid and dispersed physical development over the past decades. It has also witnessed problems such as environmental degradation, lack of attention to traditional patterns of the main urban fabric, ignorance of urban identity, etc. Meanwhile, there are abundant internal ...
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Mashhad megalopolis has experienced a rapid and dispersed physical development over the past decades. It has also witnessed problems such as environmental degradation, lack of attention to traditional patterns of the main urban fabric, ignorance of urban identity, etc. Meanwhile, there are abundant internal capacities and potentials in the city such as worn-out, less developed and undeveloped lands (including empty, abandoned, desolate ones, etc.) in the form of single lot and extensive zones, which could serve as appropriate opportunities for development and growth within the borders of the city of Mashhad. Among the districts with a high potential for development from within is District 6 of Mashhad, which about 20% of its total area is gross urban lands (such as agricultural, barren and ruinous lands). According to the Mashhad Master Plan, most of the neighborhoods in District 6 are considered to be worn-out. However, in most cases, there is room for development within the city boundaries. One of the most appropriate options for development is utilizing the infill development approach. Infill development, i.e. development from within, or endogenous development is a sort of urban development which forms on desolate, abandoned and unused lands within the limits of existing urban fabric. One of the main factors supporting infill development is urban zoning. Zoning should support infill development programs. Among the methods used in urban zoning is transect zoning which is generally one of the tools for implementing smart codes of development. In the meantime, it is important to consider the factors which support infill development strategies and policies. Due to its nature, transect zoning is considered as one of the zoning methods which can support the infill development approach. Therefore, the following article aims to provide a discussion on transect zones and to prioritize infill development strategies in these zones in District 6 of Mashhad. The study method is analytical. Documentation, field observation and survey (which includes completing questionnaires by the experts) are used for collecting data. The final weight of each criterion was calculated using the AHP method in the Expert Choice. The transect zoning of the scope was proposed after overlapping thematic maps and adding weights related to the criteria to the maps using the WOI method. SWOT analysis was been used to provide strategies. Subsequently, based on experts’ opinions, the strategies were weighed and prioritized using the Friedman test in SPSS. According to the analysis carried out in the form of AHP method in the Expert Choice, the criteria of density (0.482), texture feature (0.219), accessibility (0.114), and distance from the land use (0.064) gained the most weight among the transect zoning criteria. The case study was classified into four T-zones (T1, T2, T3, T4) and two special zones (agricultural and power station zones). Also, the most important infill development strategies for T-zones of the city core were respectively identified to be restoring unused lands to the cycle of city activity (S4O3: 0.107), reduction of activity incompatibility (W3T3: 0.103) and strengthening public participation (W2T3: 0.1).
Urban Design
elham zabetian
Abstract
A public urban space is successful when it attracts the citizens. The climate and thermal comfort conditions are factors affecting the usage pattern of sidewalks in public urban spaces. In general, awareness of sensory information and understanding of their complex process is called perception. Psychological ...
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A public urban space is successful when it attracts the citizens. The climate and thermal comfort conditions are factors affecting the usage pattern of sidewalks in public urban spaces. In general, awareness of sensory information and understanding of their complex process is called perception. Psychological aspects and their impact on the evaluation of thermal comfort makes a different perception of thermal sensation. Adaptation is the most important psychological factor affecting thermal comfort perception. Thus, the present article tries to develop an empirical model based on the studies assessing thermal psychological adaptation that can be tested in the future researches on several urban spaces. The empirical model is constructed through a conceptualization process based on a study of the basics and successful experiences worldwide. The model’s accuracy was first improved through inquiring ideas from 27 experts in this field and, second, taking advantage of Delphi’s reciprocal method. In the next stage, the aspects, scales and the subscales in the empirical model were ranked based on analytic hierarchical method (AHP). Expert Choice was used to determine each scale’s weight relative to its counterpart. In fact, the empirical model was applied to evaluate the studied concept. The model has two parts: a part assessing sense of place and another part assessing the psychological adaptation of thermal comfort. Based on the results, it can be argued that a model is necessary for blending the objective and subjective issues influencing the assessment of an individual’s adaptation for moving towards comfort in an urban space, because adaptation is a very important capability in enhancing the individuals’ presence in an urban space. Psychological reasons are the most important factors contributing to the adaptation enhancement. On the other hand, based on the studies conducted on the sense of place (that can be classified into various levels from alienation to devotion to place), such a sense can be effective in the creation of psychological adaptation that, in turn, is influential on the perceptions of comfort. Comfort is a multifaceted concept with many aspects that renders any research complicated. Thus, as an entry for such types of studies within the context of the urban design, this study attempts to concentrate only on one of its most important parts, i.e. thermal comfort. As it can be understood from a review of the global experiences in regard to thermal comfort perception, the thermal comfort perception and the thermal sense of individuals differ: the citizens can adapt themselves to the environmental comfort conditions for certain reasons (stemming from various levels of sense of place based on the findings of the current research), or, quite inversely, they could have lower adaptation threshold and leave the environment. The empirical model designed for assessing the relationship between the sense of place and thermal psychological adaptation in an urban space consists of various levels that are influenced by the individual factors. Thus, making plans for managing citizens’ behaviors in the urban space is a factor more important than physical planning to enhance citizens’ perceived level of comfort.
Urban Transport
shahrzad moghadam; zohre fani; mohamad taghi razaviyan
Abstract
Nowadays, the cities are rapidly transforming due to such reasons as the spatial structure, economic and social relations. Therefore, they need new approaches in urban management. Urban spaces are physical manifestation of citizens’ social needs and provide the necessary groundwork for access and ...
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Nowadays, the cities are rapidly transforming due to such reasons as the spatial structure, economic and social relations. Therefore, they need new approaches in urban management. Urban spaces are physical manifestation of citizens’ social needs and provide the necessary groundwork for access and provision of services required by users. They make the conditions for all users (men and women) to fairly use and enjoy the urban space. The purpose of this study is to identify and analyze the factors influencing women’s travel behavior in Zanjan. The study is an applied research and the methodology is descriptive-analytical. The statistical population includes 15-50 year old women in Zanjan. The sample size was determined using Cochran’s C test (384 questionnaires) and the samples were selected through random sampling method. In the present study, we first aimed at investigating and identifying urban traffic patterns based on theoretical foundations and 9 components. Questions are quantified on the Likert scale and Gutmann spectrum. Then, the patterns of women’s traffic in the city and its significant difference from the various forms of urban transport system are analyzed using these indicators. Data was analyzed in SPSS, using Kruskal-Wallis test, analysis of variance and correlation tests. Cronbach’s alpha coefficient was used to test the reliability of questions. Information obtained from the questionnaires indicated a relationship between car ownership, occupation, family structure and travel behavior. Results show that owning a personal car leads to more mobility among employed women. In addition, women who have children are more dependent on personal cars than men, because they are not satisfied with the performance of urban public transportation. The results of this research indicate that women’s needs are not considered in urban transport planning. With the differentiation of functions in cities, transportation has affected the social and economic dimensions of women’s lives in the city.In addition, couples with children mostly use personal cars for transportation. This is apparent from the great difference in the average personal car usage in the group of women with children owning personal cars (54.56) and women without children with personal car ownership (20.6). Employed women drive more than housewives; they tend to use personal cars. Higher comfort, speed and safety are the reasons for driving personal cars rather than using other urban transportation forms. Women’s dissatisfaction with the public transport system (0.033) can be one of the several factors in increased traffic congestion and dependence on personal cars in the urban transport system of Zanjan. Housewives who own personal cars do not advise the use of public transport system. They will use alternative methods if the condition of public transportation improves.