• Journal of Environmental Science International
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• v.26 no.4
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• pp.467-481
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• 2017

This study sought to determine the changes in weather conditions in urban streets, along with conditions of traffic and roads in urban areas. The variations in weather conditions depending on traffic differed according to distance. First, the temperature difference measured by traffic results is as follows: T1 point $1.03^{\circ}C$, T2 point $1.04^{\circ}C$, T3 point $0.9^{\circ}C$, T4 point $1.01^{\circ}C$, and T5 point $0.31^{\circ}C$. The average difference between the measured temperatures by the point of measurement was $0.86^{\circ}C$. The changes in wind velocity according to traffic volume results of the measurements is T1 point 1.32 m/s, T2 point 0.80 m/s, T3 point 0.29 m/s, T4 point 0.04 m/s, and T5 point 0.09 m/s. The difference between the average wind speeds was 0.51 m/s and traffic jams caused substantial differences in distance. The relative humidity tended to be inversely proportional to temperature. The measurements results ares T1 point 2.29%, T2 point 2.67%, T3 point 2.47%, T4 point 2.16%, and T5 point 0.91% The difference between the average relative humidity was 7.3%. In case of independent sampling T test according to traffic volume, changes in wind velocity and temperature were directly proportional to the level of statistical significance(p<0.01). On the other hand, relative humidity tended to be inversely proportional; however, there was no statistical significance.

• Earthquakes and Structures
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• v.9 no.6
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• pp.1153-1179
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• 2015

This paper focuses on presenting modeling considerations and insight into the performance of typical straight, curved, and skewed box-girder bridges in California which form the bulk of the bridge inventory in the state. Three case study bridges are chosen: Meloland Road Overpass, Northwest Connector of Interstate 10/215 Interchange, and Painter Street Overpass, having straight, curved, and skewed superstructures, respectively. The efficacy of nonlinear dynamic analysis is established by comparing the response from analytical models to the recorded strong motion data. Finally insights are provided on the component behavioral characteristics and shift in vulnerability for each of the bridge types considered.

• Journal of the Korean Association of Geographic Information Studies
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• v.27 no.2
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• pp.1-18
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• 2024

This study aimed to identify the optimal street tree planting method to improve the summer thermal environment in Seoul, Republic of Korea. The effects of road direction and street tree planting patterns on urban thermal environments using ENVI-met simulations were analyzed. The 68 scenarios were analyzed based on four road directions and 17 planting patterns. The results showed that tree planting had a reducing air temperature, mean radiant temperature, human thermal sensation (PET and UTCI). The most effective planting pattern among all scenarios was low tree height (6m), wide crown width (9m), high leaf area index (3.0), and narrow planting interval (8m). The largest improvement in the thermal environment was the northern sidewalk of the east-west road. Since this study used computer simulations, the difference from real urban spaces should be considered, and further research is needed through field measurement and consideration of more variables.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.362-365
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• 2007

In this paper we present development process and results of some cases for underground pad transformer and switchgear. Some characteristic factors was considered and tested to improve the functions of the case, such as natural convection of cooling air between the internal and external cases, properties of material that used as external panel etc. Proposed designs and functional characteristics will be adapted to making the cases of underground facilities after the elaborated tests. The results obtained from this study will improve the scenery of a street.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1066_1067
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• 2009

Wind power is one of most promising renewable energy. The output capacity of large wind turbine has been increased for off-shore application. Number of installation of small wind turbine also has been increased for the stand-alone and off-grid application of remote area and recently small wind turbine equipped with lamp on the pole is used for street lamp. Maximum wind energy must be extracted by wind turbine within rated wind speed. Power must be controlled to protect the system such as blade, generator, and power system above the rated wind speed. In this paper, small wind power system of 800W rating for battery charging is implemented and output power control by furling system is verified at wind tunnel test.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.203-204
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• 2000

도시협곡 내에서 형성되는 전형적인 유동장은 협곡내부에서 형성되는 회전류(vortex)이다(Berkowicz, 1998). Oke(1988)에 따르면 단면비가 큰 경우 (W/H＞2.5), 도시 협곡내 유동장은 isolated roughness flow, 단면비가 중간인 경우(1.538

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1619-1629
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• 2013

It turned out that there was a direct or an indirect relationship among global warming, urban heat island effects, urban and traffic environments, and public's health. In particular, unusual climate phenomena such as frequent heavy rainfall and scorching heat in a row that had rarely happened before have a negative effect on quality of life for people living in urban areas. This study focuses on the effects of roadway geometric design and traffic conditions on air temperature of roadside in Seoul Metropolitan Areas, controlling of roadway micro-climate environment. Five roadway segments containing different roadway and traffic conditions in terms of traffic median with trees, street trees, traffic volume and average travel speeds were surveyed. According to statistical results(t-test) from three roadway air temperature regression model estimations, air temperature is found to be different from one another in three periods-morning, afternoon and evening. Regarding roadway geometric design, air temperature of urban roads with vegetated median strips is lower about 1.3~2.2 degrees in celcius. Higher traffic volumes per lane and lower average travel speeds will tend to increase roadside air temperature, and efficient traffic operation policies can protect from increasing roadside air temperature in urban areas.

• The Korean Journal of Ecology
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• v.21 no.4
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• pp.337-344
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• 1998

To select tolerant species among the Korean major woody plants for restoring disturbed ecosystems by air and soil pollution, we transplanted the seedlings of 56 species in control and polluted sites within Yeocheon industrial complex area, and compared their aboveground growth characteristics such as total branch length, total leaf weight, and maximum photozynthetic rate. Tolerant species growting better in polluted site than in control site was Quercus variabilis, Pinus thunbergii, Q. aliena, P. densiflora, Styrax japonica, Alnus firma, Celtis sinensis, Elaeagnus umbellata, Q. serrata, japonica, Sorbus alnifolia, and Q. acutissimia in local tree occuring within polluted area group (80%), Ailanthus altissima in street tree group (20%), Populus tomentiglandulosa and A. hirsuta var. sibirica in fast growing tree group (50%), Acer ginala and Abies holophylla in late successional tree group (20%), Betulla platyphylla var. japonica, Acer truncatum, A. palmatum, Syringa dilatata, and Rosa multifora in garden tree group (38%), and Q. rubura, and Robinia pseudoacacia in foreign restoring tree group (20%), respectively. The remaining plant species, 37 species (57% of total species), were classified into sensitive species to pollution. Those tolerant species can be utilized for restoration of the degraded ecosystem in this polluted area.

• Atmosphere
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• v.29 no.4
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• pp.417-427
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• 2019

The purpose of this study is to build urban canopy model (Met Office Reading Urban Surface Exchange Scheme, MORUSES) based to Unified Model (UM) by using urban building information data in Seoul, and then to compare the improving urban canopy model simulation result with that of Seoul Automatic Weather Station (AWS) observation site data. UM-MORUSES is based on building information database in London, we performed a sensitivity experiment of UM-MOURSES model using urban building information database in Seoul. Geographic Information System (GIS) analysis of 1.5 km resolution Seoul building data is applied instead of London building information data. Frontal-area index and planar-area index of Seoul are used to calculate building height. The height of the highest building in Seoul is 40m, showing high in Yeoido-gu, Gangnam-gu and Jamsil-gu areas. The street aspect ratio is high in Gangnam-gu, and the repetition rate of buildings is lower in Eunpyeong-gu and Gangbuk-gu. UM-MORUSES model is improved to consider the building geometry parameter in Seoul. It is noticed that the Root Mean Square Error (RMSE) of wind speed is decreases from 0.8 to 0.6 m s^-1 by 25 number AWS in Seoul. The surface air temperature forecast tends to underestimate in pre-improvement model, while it is improved at night time by UM-MORUSES model. This study shows that the post-improvement UM-MORUSES model can provide detailed Seoul building information data and accurate surface air temperature and wind speed in urban region.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.229-239
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• 1998

This study investigated ecological and growth characteristics of Sorbus alnifolia for usage of landscape woody plant. The results are obtained as follows: 1) The results of investigate the native Sorbus alnifolia vegetations in Seoul and Kyonggi-do are as follows. From the investigation of canopy and understory, Pinus densiflora, Pinus rigida, Quercus mongolica Quercus dentata and Quercus aliena grow well in natural habitat of Sorbus alnifolia. While Rhod. mucronulatum, Symplocos chinensis, Corylus hetrophylla and alnifolia. While Rhod. mucronulatum, Symplocos chinensis, Corylus hetrophylla and Lindera obtusiloba are commonly found from shrub structure in the habitat. These structure pattern of natural setting would be applied for ecological planting design. 2) The Mt. Rabong area, which locates near a heavy factory district and is considered as environmental dteriorated area has the lowest soil acidity range among three investigated area. Sorbus alnifolia grows in where contains low soil acidity and inorganic nutrient. It might concluded that Sorbus alnifolia be tolerates to air pollution. 3) From the investigation of good specimen tres, the oldest good specimen trees of Sorbus alnifolia have grown in Seoul and Kyonggi-Do for 130 years with 15m height and 12m width. Most of good specimen trees are over 50 years old with 10~15m height, 4.5-12m width. These growth shape and form could be recommend that Sorbus alnifolia would be used as street tree and landscape woody plant in urban park.