Public Transport Density Research Articles

공영자전거 이용에 영향을 미치는 지역적 환경특성 연구 - 창원시 공영자전거 OD데이터를 활용한 공간정보 분석 -

Urban transportation system is usually interactive with land use planning. Therefore, urban characteristics should be taken account to facilitate bicycle use in an urban area. The former way of drawing out traffic density projection was considered to be inadequate since by force of habit, transportation planning and complex development did not impose simultaneously but in a particular sequence. This study aims to establish an activation plan for the Public bicycles use and draw out factors for bicycle station's selection of location through analyzing space correlation between urban characteristics and the usage of the Public bicycles. The analyzed result in the case of Changwon-si shows that there is a spatial autocorrelation between two factors. Moreover, it also arrived at the conclusion that Spatial Lagged Model and Spatial Error Model has 10% higher relevancy than Ordinary Least Square. The operation of Spatial Lagged Model arranges factors in order of correlation: main facility's total floor area, public transportation density, traffic accident rate, and population density.

Polychlorinated dibenzo- p-dioxin and dibenzofuran in urban air of an Andean city

Particle-bound polychlorinated dibenzo- p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in ambient air were monitored together with particulate matter less than 10 μm (PM 10) at three sampling sites of the Andean city of Manizales, Colombia; during September 2009 and July 2010. PCDD/Fs ambient air emissions ranged from 1 fg WHO-TEQ m −3 to 52 fg WHO-TEQ m −3 in particulate fraction. The PM 10 concentrations ranged from 23 μg m −3 to 54 μg m −3. Concentrations of PM 10 and PCDD/Fs in ambient air observed for Manizales – a medium sized city with a population of 380 000 – were comparable to concentrations in larger cities. The highest concentrations of PCDD/Fs and PM 10 found in this study were determined at the central zone of the city, characterized by public transportation density, where diesel as principal fuel is used. In addition, hypothetical gas fractions of PCDD/Fs were calculated from theoretical K p data. Congener profiles of PCDD/Fs exhibited ratios associated with different combustion sources at the different sampling locations, ranging from steel recycling to gasoline and diesel engines. Taking into account particle and gas hypothetical fraction of PCDD/Fs, Manizales exhibited values of PCDD/Fs equivalent to rural and urban-industrial sites in the southeast and center of the city respectively. Poor correlation of PCDDs with PM 10 ( r = −0.55 and r = 0.52) suggests ambient air PCDDs were derived from various combustion sources. Stronger correlation was observed of PCDFs with PM 10. Poor correlation between precipitation and reduced PM 10 concentration in ambient air ( r = −0.45) suggested low PM 10 removal by rainfall.