مدل‌سازی فضایی عوامل موثر در تراکم ساختمانی (موردمطالعه: شهر همدان)

درک توسعۀ فضایی سیستم‌های شهری همچنان یک موضوع پیچیده و بحث‌برانگیز است. رشد فیزیکی شهرها الگوهای فضایی متفاوتی را ایجاد می‌کند که به ایجاد اثرهای اقتصادی، اجتماعی و اکولوژیکی منجر می‌شود. نحوۀ گسترش شهرها و در پی آن اتخاذ سیاست متراکم‌سازی، مقولۀ تراکم را یکی از مهم‌ترین مولفه‌های تعیین‌کنندۀ ساختار شهری مطرح کرده است. هدف پژوهش حاضر، شناسایی و مدل‌سازی عوامل اثرگذار در تراکم ساختمانی شهر همدان است. در پژوهش حاضر با نگرش توصیفی- اکتشافی و پیمایشی، تغییرات انواع تراکم و تحولات فضایی آنها در سطح محله‌های شهر همدان تحلیل شده است. طبق نتایج، تمرکز فضایی تراکم‌های مسکونی و جمعیت به‌صورت لکه‌هایی پراکنده در سطح شهر به‌ویژه در نیمۀ غربی و جنوب شرقی دیده می‌شود. الگوی تمرکز فضایی تراکم ساختمانی در شهر همدان خوشه‌ای بوده است که بیشتر به‌صورت نیم حلقه در حاشیۀ جنوبی هستۀ مرکزی دیده می‌شود. ضریب آنتروپی به‌دست‌آمده برای همۀ شاخص‌ها و متغیرها، نشان‌دهندۀ توزیع به‌نسبت متوازن آنها در محله‌های شهر است. این تعادل در شاخص تراکم ساختمانی کمتر مشاهده می‌شود. ‌شیب خط نیز برای هر دو تراکم ساختمانی و جمعیتی کاهشی بوده است؛ یعنی با فاصله از مرکز شهر مقادیر آنها کاسته می‌شود؛ همچنین با استفاده از تحلیل رگرسیون وزنی جغرافیایی، تاثیر هرکدام از متغیرهای مستقل در مدل‌سازی تراکم ساختمانی در بخش‌های مختلف شهر مشخص شده است.

spatial modeling of factors affecting building density: a case study of hamedan city

understanding the spatial development of urban systems is a complex and controversial issue. the physical growth of cities creates different spatial patterns which could lead to economic, social, and ecological effects. the purpose of this study is to identify and model the factors affecting the building density of hamadan. the present study has analyzed the changes in density types and their spatial changes in the neighborhoods of hamadan with a descriptive-exploratory and survey approach. according to the results of spatial concentration, residential densities and population are seen as scattered spots in the city, especially in the western and southeastern parts. the pattern of spatial concentration of building density in the city of hamedan is a cluster that is mostly seen as a semicircle on the southern edge of the central core. the entropy coefficient obtained for all indicators and variables shows their almost balanced distribution in urban neighborhoods, which is less observed in the building density index. the slope of the line has also been decreasing for both building and population densities, that is, their values are decreasing with the distance from the city center. also, using geographical weight regression (gwr) analysis, the effect of each of the independent variables in building density modeling in different parts of the city has been determined. introduction one of the most important features of our era is urbanization and the development of large and small towns. from the 1990s to 2030, more than three billion people will be added to urban areas, including 90 percent in urban areas of developing countries. urban congestion is therefore the inherent characteristic of urban areas where many urban indices are closely related to each other. the reduction of urban congestion increases the cost of land in urbanization. the decrease in congestion tends to lead to urban dispersal with low density, which has always been criticized for negative effects such as increased infrastructure costs. this study tries to identify and model the factors affecting the building density of hamadan and to regulate urban spaces in the development and development processes. the issue of the density and overhead of residential space is one of the main issues in the literature related to urban studies. extensive research on population density, population, and construction is a good indicator of its importance in an urban area. urban land development in developing countries has been identified in most cases as horizontal expansion and a qualified process of scattered and sparse development features. however, there is no specific dividing line between extensive and dense development. moreover, the urban land development process in many cities is not simply described as a scattered or compact expansion. despite the significant role of the density in planning and steering of the city structure, there is no definition and method of measurement, standard, and consensus about the density. however, the four indicators of population density, the gross population density, residential net concentration, and construction density have been mentioned in the literature. methodology the present study is practical in terms of nature. the method of this descriptive-analytical study is survey. the statistical population of the research is 69 neighborhoods of hamedan city in 2015. to measure the density distribution, the density analysis method was used to analyze the spatial pattern of the air density, and based on it, spatial analysis of urban congestion indices was modeled on the scale of statistical blocks with the help of the gwr method between independent variables and the dependent variable (building density). the data were finally extracted in the gis software. hamedan city is one of the western and mountainous cities of iran. this city is located on the slopes of alvand mountain at an altitude of 1740 meters above sea level