• Atmosphere
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• v.26 no.3
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• pp.423-433
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• 2016

In this study, performance of a computational fluid dynamics (CFD) model is assessed from analysis on air flow pattern which is observed in the artificial street canyon. Field observations focusing on flows were conducted at an artificial street canyon in Magok region. For the observation of three-dimensional airflow structures, twelve three-dimensional wind anemometers (hereafter, CSAT3) were installed inside the street canyon. The street canyon was composed of two rectangular buildings with 35-m length, 4-m width, and 7-m height. The street width (distance between the buildings) is 7 m, making the street aspect ratio (defined by the ratio of building height to street width) of 1. For the observation of above-building wind, a CSAT3 was installed above the northwest-side building. Southwesterly, westerly and northwesterly were dominant in the street canyon during the observations. Because wind direction is parallel to the street canyon in the southwesterly case, westerly and northwesterly were selected as inflow directions in numerical simulations using a computational fluid dynamics model developed through the collaborative research project between National Institute of Meteorological Sciences and Seoul National University (CFD_NIMR_SNU). The observations showed that a well-structured vortex flow (skimming flow) and an evidence of a small eddy at the corner of the downwind building and ground appeared. The CFD_NIMR_SNU reproduced both the observed flow patterns reasonably well, although wind speeds inside the street canyon were underestimated.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.6
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• pp.78-86
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• 2019

The study analyzed the greenness index that residents experience on the streets of rural areas, where characteristics are different from those of urban areas and the effects of these characteristics were investigated. In Yesan-gun, Chungnam, in order to analyze the greenness indices, the streets were categorized into 7 types. Then, two types of streetscape greenness indices were surveyed, analyzed, and compared. One is the street-trees greenness index which takes into account only the trees lining the street and the other is the street greenness index considering total artificial green, natural green, and productive green surfaces. As a result, using the street-tree greenness index the street greenness index of Yesan-gun was analyzed as 15.93% on national highways, 26.14% for local roads, 28.28% for gun-roads, 24.72% for myun-roads, 40.70% for li-roads, 32.78% for nong-roads, and 18.36% for urban planning roads. Using the street greenness index, the street-trees greenness index was analyzed to be 5.02% for national highways, 9.10% for local roads, 8.55% for gun-roads, 4.51% for myun-roads, 6.92% for li-roads, 2.56% for nong-roads, and 9.39% for urban planning roads. To analyze what factors have an impact on the street-trees greenness index and the street greenness index, the study analyzed the effects of street side-land uses, lane types, street-trees, and sidewalks. As a result, both the street greenness index and the street-trees greenness index responded according to the land use adjacent to the street, lane types, and sidewalks. The street greenness index did not change due to the existence of street-trees, but the street-trees greenness index did. Through comparison with other studies, it was found that Yesan-gun needs to improve its streetscape to improve its greenness index rating.

• Journal of the Korean Dietetic Association
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• v.9 no.3
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• pp.259-268
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• 2003

The purpose of this study was to investigate recognition and buying practices of street-vended foods among college students in Chungbuk Area. A general dietary practices including snacks, related factors of buying street-vended foods were analyzed. The results showed that many students had irregular dietary habit, especially more than eighty percent of them skipped breakfast. More than sixty percent of students had frequent snacks. It was investigated that college students ate street-vended foods two or three times per week. The order of frequent choice of street-vended foods was rice cake with pasted red pepper(51.9%), sweet and sour pork(19.7%), sundae(5.7%). In microbiological examination, MPN of Coliform and CFU of standard plate count was over a standard value respectively, and acid value of frying oil revealed over value for maximum limitation point. Therefore, food and equipment in street-vended food store was evaluated as poor sanitation status. Most of college students have opinion that street-vended food store must be kept the line. In conclusion, nutrition education for college students should be required to protect them from unsafe street-vended foods.

• Journal of Forest and Environmental Science
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• v.34 no.2
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• pp.162-164
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• 2018

This study quantified the carbon storage and uptake by street trees in Seoul and explored suitable planting and management strategies. A systematic sampling model was used to select 50 plots to survey the structures of street trees. The average density and cover of street trees were approximately 5.8 trees/$100m^2$ and 12.1%, respectively. Trees with a dbh of less than 30 cm accounted for about 66.3% of the total number of trees surveyed. The total carbon storage and uptake by the street trees were approximately 103,641 t and 10,992 t/yr, respectively. The total carbon uptake equaled the amount of annual carbon emissions from driving of about 11,000 cars. Street tree planting and management strategies were proposed to enhance carbon uptake. They included multi-layered and multi-aged planting, securing ground and space for plant growth, and avoiding excessive tree pruning.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.2
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• pp.214-224
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• 2007

A three-dimensional computational fluid dynamics (CFD) model with the renormalization group (RNG) $k-{\varepsilon}$ turbulence model is used to examine the effects of difference in building height on flow and pollutant dispersion in asymmetric street canyons. Three numerical experiments with different street canyons formed by two isolated buildings are performed. In the experiment with equal building height, a portal vortex is formed in the street canyon and a typical recirculation zone is formed behind the downwind building. In the experiment with the downwind building being higher than the upwind building, the ambient flow comes into the street canyon at the front of the downwind building and incoming flow diverges strongly in the street canyon. Hence, pollutants released therein are strongly dispersed through the lateral sides of the street canyon. In the experiment with the upwind building being higher than the downwind building, a large recirculation zone is formed behind the upwind building, which is disturbed by the downwind building. Pollutants are weakly dispersed from the street canyon and the residue concentration ratio is largest among the three experiments. This study shows that the difference in upwind and downwind building height significantly influences flow and pollutant dispersion in and around the street canyon.

• Current Research on Agriculture and Life Sciences
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• v.25
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• pp.19-23
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• 2007

This research to streets at Daegu, and view adjective how people react when draw a bird into interior in city utilize and examine becoming direction of street trees system. Findings on survey, citizens appear by average 2.87 in management degree of street trees and average 2.76 in various of species of trees, discontent thing more or less by average 2.91 in satisfaction of the beauty, and demonstrate high shame from satisfaction for season stuff to comparative high 3.24, generally, citizens appear by there are parts to improve by do dissatisfaction about street trees system at Daegu. Also, street trees 2 lines plantings for a bird is average 3.05, shows affirmative feedback about that shrub utilization for a bird see high numerical value by average 3.4 and people draw a bird to space of city. Therefore, construct street trees friendly to the nature and be considered to need to re-establish set street trees environment in citizens preference to recover city ecosystem. As result that examine reaction which treat in street trees planting programs to draw birds into city through view adjective, Likert scales about 2 lines plantings of street trees and additional planting of shrub show affirmative feedback by average 3.4 both ordinary people and specialist group, if people want to draw birds into city by various of method, various research should be accomplished.

• Atmosphere
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• v.25 no.3
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• pp.473-482
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• 2015

In this study, street canyons with a higher downwind building (so called, step-up street canyons) are considered for understanding characteristics of flow and reactive pollutants' dispersion as a basic step to understand the characteristics in wider urban areas. This study used a CFD_NIMR_SNU coupled to a chemistry module just including simple $NO_X-O_3$ photochemical reactions. First, flow characteristics are analyzed in step-up street canyons with four aspect ratios (0.33, 0.47, 0.6, 0.73) defined as ratios of upwind building heights to downwind building height. The CFD_NIMR_SNU reproduced very well the main features (that is, vortices in the street canyons) which appeared in the wind-tunnel experiment. Wind speed within the street canyons became weak as the aspect ratio increased, because volume of flow incoming over the upwind building decreased. For each step-up street canyon, chemistry transport model was integrated up to 3600 s with the time step of 0.5 s. The distribution patterns of $NO_X$ and $O_3$ were largely dependent on the mean flow patterns, however, $NO_X$ and $O_3$ concentrations were partly affected by photochemical reactions. $O_3$ concentration near the upwind lower region of the street canyons was much lower than background concentration, because there was much reduction in $O_3$ concentration due to NO titration there. Total amount of $NO_X$ in the street canyons increased with the aspect ratio, resulting from the decrease of mean wind intensity.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.4
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• pp.15-29
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• 2021

Urban green spaces offer a variety of benefits to living things and humans. However, existing green spaces have been reduced and fragmented due to urbanization, and there is a limit to creating new large green spaces in densely developed cities. Street trees have fewer restrictions on land use, which can be a measure to secure green areas in cities. In Korea, excessive pruning is being done on some street trees for reasons such as blocking of building signboards, contact with electric wires, and restrictions on sidewalk widths. Therefore, it is necessary to quantitatively understand the relationship between the benefits provided by street trees and their structures to come up with an efficient and systematic planning and management plan for urban street trees. In this study, we quantitatively analyzed the relationship between the thermal comfort improvement by the shades of street trees and the vertical structure, planting environment, and types of street trees. To calculate the thermal comfort felt by human body, we calculated UTCI (Universal Thermal Climate Index) of each street tree. For the vertical structure of street trees, we used Terrestrial LiDAR and the point clouds of street tree's crown was sliced vertically at 1m intervals. We conducted a multiple regression analysis on the thermal comfort improvement using the variables we obtained from fields. As a result, in the case of a street tree's vertical structure, the lager the volume of tree's crown located 3-4m (β=0.298, p<.05) and 6-7m (β=0.568, p<.001) above clear length, the better the cooling effect. In addition, the thermal comfort improvement was assessed to decrease as the DBH increased (β=-0.435, p<.001). In general, the crown diameter and DBH are positively correlated, with a cooling effect occurring as crown diameter increases. In this study, the opposite result was obtained due to the small number of trees measured, so additional research is needed by increasing the number of tree samples. In the case of the planting environment, the effect of improving thermal comfort was higher in the shaded area of trees planted to the south (β=-0.541, p<.001). Since unsystematic management of street trees can deteriorate the function of them, quantitative evaluations of the vertical structure of street trees are required, which can provide specific measures for planning and management of urban street trees with thermal comfort effect.

• Fashion & Textile Research Journal
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• v.10 no.1
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• pp.30-39
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• 2008

This research investigated the change of Japanese Street Fashion after the Second World War. The change were categorized into 5 terms from the late 1940s to 2000s. The first term was from the late 1940s to 1950s, when street fashion was born. The second term was from the 1960s to 1970s and counter culture of street fashion appeared. The third term was the 1980s, during which street fashion fluctuated. The forth term was the 1990s, a period of chaos in street fashion. The fifth term was after 2000 and it was a retroaction term of street fashion. Japanese street fashion was influenced by fashion magazines in those days. Various street fashions in Japan based on special society and cultural situation accomplished Japanese basic fashion quality and influenced world fashion.

• Korean Journal of Community Nutrition
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• v.14 no.4
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• pp.406-419
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• 2009

This research has been surveyed on street food and snack intake status of elementary school students in the Jeon Buk region and the recognition of mothers has been observed for the objective of providing base materials for appropriate eating habits and nutritional education. As for status on intake of street food, most students (97.3%) have shown to have eaten from the street vendors while mothers assume low frequency in their child's intake of street food. Favorite street food choices had an agreement between mother and student as ddukbokki and dakkochi. Students were more tolerant in sanitation and necessity of street food than the mothers. This research shows that there is a difference in the recognition of street food between the students and their mothers. There a need required for improvement in the system as to provide quality food and to prevent poor quality food being exposed to the students. Furthermore, practical and appropriate education must be conducted at home and at school for better choices of food and a better lifestyle. (Korean J Community Nutrition 14(4) : 406${\sim}$419, 2009)