Urban Ecology
mahsa samadpour shahrak; Mehrdad Karimimoshaver
Abstract
Highlights- The research considered the effect of planting patterns on thermal comfort.- The research addressed population increase and its effect on the morphology of cities.- The results of comparison between the scenario without trees and the others demonstrate that the thermal comfort conditions ...
Read More
Highlights- The research considered the effect of planting patterns on thermal comfort.- The research addressed population increase and its effect on the morphology of cities.- The results of comparison between the scenario without trees and the others demonstrate that the thermal comfort conditions exhibit great changes, and all the scenarios create better environmental conditions than the scenario without trees.- The findings show that simply moving vegetation and trees without changing their nature and dimensions and the environment can improve comfort to some extent. IntroductionThe increasing population has changed the morphology of cities and caused changes in the surrounding environmental conditions. Green space per capita is about 4.5 square meters in Iran, which is quite different from the global standard: 20 to 25 square meters per person (Haashemi et al., 2016). As a result, it seems necessary to increase the amount of greenery in cities. Lee et al. (2016) introduce shading and ventilation as the main factors in the improvement of thermal comfort conditions in the environment using trees. Vegetation reduces mean radiant temperature and improves environmental conditions through evaporation and daylight control and reflection (Salata et al., 2017). It plays a major role in the regulation of weather conditions by controlling and conducting wind flow and reducing wind speed and pressure (Perini et al., 2018).Theoretical FrameworkThermal comfort involves conditions of perception in which the surrounding environment is thermally satisfactory (Ashrae, 1997). In their review of the studies conducted in the field of thermal comfort in outdoor spaces, Johnson et al. have introduced the predicted survey average index as one of the most widely used indices among ones such as SET and UTCI. (Johansson et al., 2013). This index has been widely used in different regions with different climates (El-Bardisy et al., 2016; Salata et al., 2015; Abdi et al., 2020).This model was designed by Fanger in 1970, considering factors such as air temperature, average radiant temperature, and relative humidity and two personal variables including clothing resistance and activity level, used as a composite index. This index specifies the coefficients that are measured according to Asher’s thermal scale and indicates the average thermal sensation of a large group of people in a certain space (Fanger, 1970). Therefore, considering and measuring this index causes other microclimatic factors to be taken into account and obtained through the following formulae:PMV=(0.303e-0.036m+0.028)[(M-W)-H-Ec-crec-Erec]E=3.05×10-3(256tsk-3373-pa)+EswEc=3.05×10-3[6.99×5733(M-W)-pa]+0.42(M-W-58.15)Crec=0.0014M(34-Ta)Erec=1.72×10-5M(5867-Pa).The value of H can be measured directly and calculated using the following equation:H=Kcl=tsk-tcl/Icl.Moreover, previous research has pointed out the importance of planting patterns, trees, and vegetation and their impact on the environmental and microclimatic conditions of the region. The question that arises now is what kind of tree planting pattern, among the common ones, can have a better impact on the environment. In this study, therefore, the four common planting patterns of sextuple, quadruple, row, and scattered were selected to be applied in the same conditions and with the same number of trees.MethodologyIn this research, the ENVI-met software was used because the output provides most of the parameters required for thermal comfort, such as Ta, Tmrt, and wind speed (Taleghani et al., 2015), and the results have been validated and used by researchers (Taleghani et al., 2018). For data measurement, five receptors were selected at the central points of the site. These receptors were located so as to be scattered in the site and be capable of expressing the general state thereof. Therefore, three receptors at the central points of the site and two located around the site were selected. Moreover, because the average human height between the positions of sitting and standing is 1.50 meters, the simulation measurement was carried out at this height. The environmental data and information on the receptors were extracted during the study hours (10 am to 9 pm), and the average value was calculated for the predicted survey average index.Results and DiscussionThe analysis of the data and figures extracted from the software demonstrates that a more uniform shade is created in the environment in the scattered pattern than in the others, and because the trees are scattered in most parts of the site, solar access is more limited there than in the other scenarios. Moreover, ventilation conditions are easier in the row pattern than in the scattered pattern, and the warm wind passes through the trees more easily there due to the regular arrangement. Therefore, the best planting pattern is the one that creates the more uniform shade and better ventilation conditions. However, the results of the scattered pattern are the same in most parts of the site, and there is only a little difference between them in some cases. As a result, the scattered and row patterns of tree planting are better than mass planting and concentrated in certain parts of the site.ConclusionThe results of comparing the treeless scenario to the others demonstrate that the thermal comfort conditions change to a large extent, and all scenarios create better environmental conditions than the treeless state. Moreover, because the row pattern exhibits a lower average PMV for most receptors and most hours of the day, it is the best pattern. The sextuple pattern has high indices in most cases, and the quadruple pattern has a similar function to the sextuple one. Therefore, it can be concluded that the row and scattered patterns create better comfort conditions than the others. The results of this research can be used by architects, landscape designers, and urban designers. In this research, different patterns of trees have been compared, so future research can involve comparison of other plantings such as grass and shrubs and of the effects of different planting patterns.
Urban Scape
Mohammad Azad Ahmadi; Mehrdad Karimimoshaver; Saeid Alitajer
Abstract
Highlights The quality of urban views leaves desirable or undesirable emotional responses on people. City is a homogeneous or heterogeneous network of diversity of urban views to upgrade or diminish citizen's emotions. Introduction The appearance of a city can influence the creation of good or ...
Read More
Highlights The quality of urban views leaves desirable or undesirable emotional responses on people. City is a homogeneous or heterogeneous network of diversity of urban views to upgrade or diminish citizen's emotions. Introduction The appearance of a city can influence the creation of good or bad feelings to a large extent, depending on the structure and characteristics of the physical elements of the city. Citizens remember a city with an image of its urban spaces, especially the streets and squares, or of certain views, and it is their experience of the city’s physical environment that creates the image. On that basis, visual perception of the physical spaces of the city has a greater effect than other senses on the creation of different emotions in citizens. Appropriate urban views can play an effective role in the formation of clear, legible perceptions in people and in the acquisition of pleasant feelings about the city. Moreover, different perspectives can have different visual effects on the citizens of a city. A large number of studies have been carried out so far on various aspects of urban view. The present research analyzed urban views and their visual impacts on citizens, and sought to identify them along with methods of their categorization and explanation and conditions and factors that create and influence them. Urban views can have two major impacts on citizens in the form of likes and positive emotions or dislikes and negative emotions. Accordingly, attempts were made in this study to categorize the effects of urban views in general, which helped to draw the final conclusion. Theoretical framework Data collection and analysis was based in this study on an interpretive paradigm within a contextual examination of popular feedback from urban perspectives and expert views thereon. Hence, the main framework of this research was based on Jack Nasar’s definition of mental activity and emotion. He argues that the environment involves a large number of variables, and viewers go through some, pay attention to others, and evaluate what they see depending on internal and environmental factors. This assessment can include variable amounts of mental activity, and may also involve emotion, which is directly related to the structure of the form (visual environment), and requires little perception and mental activity. Methodology Due to the nature of this research, the main approach adopted in the design was a qualitative one using the grounded theory method, based on Corbin and Strauss’ approach, including open coding, axial coding, and selective coding data analysis. Other important reasons besides the comprehensive nature of the research included the nature of the research questions and the lack of an established theory on classification of urban views. Attempts were made here to step into the participants’ world and observe the subject from their point of view, to achieve new discoveries in the field, and to develop empirical knowledge in the field. The researcher first selected the sources of information and observation, and then used data from the participants for exploration and completion of the final model. The data were collected through library and field studies, interviews, and semi-structured questionnaires. The population and the participants were selected using theoretical sampling, where sampling continues until the data are saturated. The participants in this research included residents of and experts in Sanandaj. Results and discussion The results of the research showed the selective categories of observation effects and emotional responses including excitement, relaxation, pleasantness, and communication. Moreover, the causal conditions that create urban views, the contextual conditions, and the intervening conditions and their effects were obtained. The relationship between these categories and the outcome of the research was formulated and presented in a comprehensive model. The final core category was also summarized in the statement The city is a homogeneous or heterogeneous network of diverse urban views developed to upgrade or diminish citizens’ emotions. Conclusion The study demonstrated that a large number of factors are involved in identification and analysis of an urban view, in isolation and with respect to each other. Therefore, an urban view is highly complex, and is not easy to compare to another, with many factors involved to be examined and analyzed. It is better for the effects of different views on a city to be proportionate, so that their effects on citizens are desirable and balanced in the long run. For example, axial views may evoke a sense of dynamism or boredom in citizens, but broad or panoramic views may be exhilarating. According to the principle of diversity and complexity in aesthetics, these effects had better be combined, intertwined, and coexistent in a balanced manner for citizens’ different applications in response to their different emotional and spiritual states.
Urban Design
Mehrdad Karimimoshaver; hasan sajjadzadeh; hossein troosheh
Abstract
This study addressed the relationship between high-rise buildings (as part of the urban environment) and mental health (one of the three major aspects of health: physical, psychological, and social), investigating citizens’ points of view on the high-rise Saeedieh Condominium in Hamadan, Iran. ...
Read More
This study addressed the relationship between high-rise buildings (as part of the urban environment) and mental health (one of the three major aspects of health: physical, psychological, and social), investigating citizens’ points of view on the high-rise Saeedieh Condominium in Hamadan, Iran. The research sought to capture the influence mechanism and to help reinforce the insight of designers of such buildings into and their concern for features of the built environment from citizens’ perspective that can inadvertently affect their mental health. In recent decades, construction of high-rise buildings has been appealed to widely as a method of construction, replacing the horizontal growth of cities. However, it seems that vertical urbanism has paid little attention to citizens’ psychological aspects in urban spaces. Height is an intrinsic part of high-rise buildings and their most important formal feature, with a significant impact on citizens and their eventual perceptions and emotions, which makes it significant to scrutinize its influence. One of the most important issues is the impact of high-rise buildings on citizens’ mental health. Mental stresses constantly threaten human mental health, in part due to inappropriate urban environments and residences. This increases the significance of examining the urban environment to reduce the existing stresses. The purpose of this paper was to present better ways of designing high-rise buildings considering their impact on citizens’ mental health as well as to identify how the influence works. Therefore, the main questions of the study are as follows. What relationship is there between high-rise buildings and citizens’ mental health? How can height affect citizens’ mental health? In the present study, a qualitative approach was taken using the method of Grounded Theory. After in-depth interviews made in person with citizens, the transcripts were summarized and encoded in the three open, axial, and selective stages, and the grounded model was finally extracted by the MAXQDA data analysis software. The participants in the interviews included 24 citizens, 13 men and 11 women aged 17-65 years. Theoretical consecutive purposive sampling was used, where sampling would continue until adequacy (saturation) was achieved for theorization. It should be noted that saturation was achieved as felt by the researcher with comments from 8 men and 8 women—a total of 16 participants—, but the interviews continued, amounting to 24 with 8 additional ones, which served to ensure the achievement of saturation (although no changes were made in the eventual data). The findings demonstrated that high-rise buildings cause mental pressure in citizens due to issues such as improper enclosure, physical-visual consequences, sub-climate generation, landscape restrictions, social difficulties, overlook, urban area heterogeneity, and negative environmental effects and citizens’ long-term involvement in emotional reactions resulting from the mental pressure affects their mental health. With a frequency of 73, the issue of improper enclosure was found to be the most popular among citizens in the set of situational issues, playing a major role in the emergence of the interactive issues and the consequential ones as a result. It was followed by the issues sub-climate generation (with a frequency of 57), physical-visual consequences (with a frequency of 55), landscape restrictions (with a frequency of 30), urban area heterogeneity (with a frequency of 25), overlook (with a frequency of 22), and social difficulties (with a frequency of 12), in that order.
Urban Design
sajjad zolfigol; mehrdad Karimi moshaver
Abstract
A quick view of the public spaces in each city would reveal the role of the square as a built environment. Assessment of “city life” involves a qualitative evaluation of different activities and the way different people perform them (group or individual activities, state of activities, the ...
Read More
A quick view of the public spaces in each city would reveal the role of the square as a built environment. Assessment of “city life” involves a qualitative evaluation of different activities and the way different people perform them (group or individual activities, state of activities, the time of each activity). An environment that plays the role of an urban node in cities is recognized as the place of presence of different social groups and the physical realm of sustainable social interaction. The latest urban developments, expansion of cities and increased number of vehicles make squares act as a node to solve the traffic problem of cities while the first-made squares were intended for the presence of humans and social relationships in urban realms. In fact, prior to addressing the effect of humans and environment (separately without considering their relationship) on urban design and urban space, it is essential to understand their relations, the ways they are related, and the causes and effects of such relationships. Indeed, human, environment and their relationship should be considered in the urban design process. The relation between humans and environment is a process that connects them and provides the possibility of social interactions. Urban space is full of actions and reactions of people with specific behaviors and behavior settings. People’s presence in public spaces and social communities, the dynamic behavior of users, increased people’s spirit and appropriate use of public space are helpful in having a prosperous and dynamic society. Therefore, human activity, as a determining factor in improving the form and meaning attributes of a place, can result in vitalizing and diversifying the place. The behavior setting theory announces that it can be considered as a basic unit for an environment that simultaneously includes physical and social factors in the whole frame and affects user behavior. Behavior settings are real units of environment that naturally occur and are identifiable for people inside those settings because they have relationships with their daily life. The significance of the relationship between humans and urban environment, especially squares that have a vital role in urban spaces, reveals the importance of this research. The primary goal of this research is reviewing the relationship between users and environmental quality in order to improve intelligent designs for people. This practical research applies such techniques as documentary review, non-participant observation and survey. Field notes were obtained through observation and perception of users’ behaviors. The obtained data was analyzed in SPSS22 software. The analyses, conducted for several distinct purposes, overlap to some extent, while, at the same time, leaving many other possible applications behind. While a design framework is often cited as the reason for conducting these analyses, a still more systematic way to approach behavior analyses in urban design is required with the potential to supplement and extend the traditional methods with new layers referring to temporary and spatial behavior. The result points out that people are equally involved with social and physical aspects of Bu Ali Sina square. The users prefer behavior settings that provide the grounds for gathering, creating social behaviors, visiting friends and strangers, and doing different activities with a unifying meaning.
Urban Scape
Mohammad Azad Ahmadi; Mehrdad Karimi Moshaver
Abstract
Today, the issue of visibility assessment and visual impact (dominance) of a building on its surrounding context is considered as one of the most important issues of urban landscape. Accordingly, this paper analyzes the visibility of two high-rise buildings in the center and west of Sanandaj using raw ...
Read More
Today, the issue of visibility assessment and visual impact (dominance) of a building on its surrounding context is considered as one of the most important issues of urban landscape. Accordingly, this paper analyzes the visibility of two high-rise buildings in the center and west of Sanandaj using raw input data and processing them by GIS and ArcGis 10. For the visibility analysis in urban landscape, the mutual visibility between high-rise building and its surrounding area is calculated. This is done traditionally by taking photos from urban areas. However, in this method, the whole region is studied by considering all points and places. The available vegetation such as trees with an approximate transparency ratio is considered to obtain more accurate results. Also, for better evaluation of differences between the amount and trend of visibility, the areas around both buildings (region number 1 is relatively flat and has a river-valley with low depth and mild slope; region number 2 involves dune hills) were classified into the close, intermediate and far fields. The visibility of these two high-rise buildings in their surrounding areas is in the form of output GIS images which is calculated separately for both buildings and all their floors. It means that for building number 1, which has 17 floors, 17 output maps of visibility to surrounding areas are obtained by the software. Also, for building number 2 with 14 floors, 14 output visibility maps are obtained. The findings show that visibility trend of different floors of these two buildings is not a constant and linear trend, it has variations in some points. Among these points, visibility and its effect, relative to surrounding areas, is more important than other floors in the triple fields. The points where visibility curve has track change, steep change and sudden increase show the greater importance of their visibility and their relative dominance than other floors. These floors can visually have more effect on their surrounding environment. Therefore, the design style of these particular floors (milestones in the visibility curve) in high-rise buildings can be important. The changes in floors visibility trend and their values were different for the two buildings. By evaluating the related diagrams, the reasons for this difference were found in three cases: first, the difference in average height of buildings around of two buildings; second, the difference between the tilt around the two buildings; and third, the dune hill in region number 2. Finally, we can say that visibility analysis is considered to be a tool for modeling the visibility in planning high-rise buildings. Before constructing such buildings, visibility analysis can be an effective method to estimate that a floor or an apartment will or will not have a good view after completion. Therefore, this tool can be used to investigate the positive or negative value of a region. Also, the extent to which a building is or is not visible can be very important in decisions about determining the height of a building relative to its surrounding texture (especially in cities with historically valuable texture and touristic landscape).
