• 한국환경과학회지
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• 제13권1호
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• pp.27-36
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• 2004

Present study analyzed the temporal and spatial characteristics of PM10 pollution in Metropolitan Daegu area based on air pollution monitoring station data and measurements of PM10 concentrations in background area in order to provide essential data for efficient PM10 pollution management. The significant variation of spatial and temporal PM10 concentrations in Daegu area was observed during the study years. The highest maximum PM10 concentration(332 $\mu\textrm{g}$/㎥), average concentration(88 $\mu\textrm{g}$/㎥) and frequency exceeding PM10 daily standard(150 $\mu\textrm{g}$/㎥) were all observed in Namsandong located near a major roadway. The hourly and weekly variations of PM10 concentrations had different pattern for the measurement sites. The monthly and seasonal concentrations exhibited a notable characteristic： the maximum concentration was obtained in spring season, most likely due to Yellow sand effects. Furthermore, this temporal variation of PM10 pollution varied with study site. Meanwhile, the PM10 values measured at the monitoring site, Manchondong, were comparable with those of a control site. The average PM10 concentration ranged from 23 $\mu\textrm{g}$/㎥ to 115 $\mu\textrm{g}$/㎥ with a mean value of 53 $\mu\textrm{g}$/㎥ in the former site and from 22 $\mu\textrm{g}$/㎥ to 91 $\mu\textrm{g}$/㎥ with a mean value of 45 $\mu\textrm{g}$/㎥ in the latter site.

• Earthquakes and Structures
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• 제15권1호
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• pp.1-8
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• 2018

A new site classification system and site coefficients based on local site conditions in Korea were developed and implemented as a part of minimum design load requirements for general seismic design. The new site classification system adopted bedrock depth and average shear wave velocity of soil above the bedrock as parameters for site classification. These code provisions were passed through a public hearing process before it was enacted. The public hearing process recommended to modify the naming of site classes and adjust the amplification factors so that the level of short-period amplification is suitable for economical seismic design. In this paper, the new code provisions were assessed using dynamic centrifuge tests and by comparing the design response spectra (DRS) with records from 2016 Gyeongju earthquake, the largest earthquake in history of instrumental seismic observation in Korea. The dynamic centrifuge tests were performed to simulate the representative Korean site conditions, such as shallow depth to bedrock and short-period amplification characteristics, and the results corroborated with the new DRS. The Gyeongju earthquake records also showed good agreement with the DRS. In summary, the new code provisions are reliable for representing the site amplification characteristic of shallow bedrock condition in Korea.

• 교육시설
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• 제11권4호
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• pp.15-24
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• 2004

The purpose of this study is to suggest some alternative on site planning of elementary school through investigating the effects of geographical and urban environment on the site. For this, we selected and surveyed 35 schools in Gwangju. The results of this study are as follows. 1) We cannot find out the differences from the use of elementary schools sites on slopes of sites. However, the sunken space between H type buildings in the site slopes facing east or west and the placing the playground on the north side of the site slopes facing north have some problems 2) The number of adjacent road and surrounding environment didn't show any effect. To separate between cars and pedestrians, we need some plans to block cars on the pedestrian gateway and it is much better to intensify the parking area near the school gate that cars come in and out. 3) The degree of satisfaction on the outdoor facilities of these cases shows low level. Therefore, to use the site of schools efficiently, we should secure the spacious playground and make plans to provide some spaces around school building for the static activities of students and teachers. 4) Most of all, the site which is suitable for educational environment should be selected. and also Special Code on the urban plan should be established to develop this one.

• 한국환경보건학회지
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• 제28권2호
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• pp.99-108
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• 2002

This study was carried out to evaluate the Physicochemical characteristics of mined waste(separated waste and soil) and to predict environmental effect of an old landfill site located at north of Seoul. Municipal solid waster(MSW) had been disposed of at the old landfill site used in this study for about 2 years(1990-1992). The old landfill site selected for this study had accepted mainly municipal solid waste. The landfill-mined waste contained separated waste (40.9%) and soil(59.1%) by wet weight basis. The separated waste consisted of combustible(91.0%) and non-combustible(9.0%). The combustible waste was mainly non-biodegradable plastics. The low heating value of the separated combustible waste, which is calculated by Dulong's equation, was as high as 3,470kcal/kg. According to the Korean Extraction Procedure, separated waste and soil were proved to be not hazardous. The total content of heavy metal in the separated waste and soil met standard of California State, USA. Therefore the separated waste may be relandfilled at a sanitary landfill site and/or burned up at an incinerator, and the separated old soil may be used ad landfill cover-soil at a sanitary landfill site. Water quality of two streams was grade IV, of which water could be used as industrial and agricultural water. The streams near the landfill site might not be contaminated by leachate from the old landfill site. It was estimated that organic matter in the old landfill site would not be actively biodegraded within a short period of time.

• 건축역사연구
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• 제7권4호
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• pp.93-102
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• 1998

There are several treatises about architectural characteristics of Hyangkyo. But those treatises usually treat with the types of site plans or structural characteristics without the historic background. So there needs the approaching methods with the historic background to study about the architecture of Hyangky. This study aims at the sample research about the architecture of Hyangkyo in beginnig period. Kyodong hyangkyo is the first building in hyangkyo. There are some architectural characteristics in this building comparing with the Hyangkyo in ripening period. Such characteristics apper in the site plan of educational spaces and in the floor plans of Myongryundang, Dongjae, Seojae. And there appear some characteristecs in ritual spaces such as the architectural structure of Daesungjun, and the position of stone establishment (Kwansedae, Saengdan) The ritual form of Kyodong hyangkyo has no special characteristics compering with the Hyangkyo in ripening period. These rictual form has kept the general rule of ritura form through the history.

• 한국지진공학회논문집
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• 제20권4호
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• pp.245-256
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• 2016

In the companion paper (I - Database and Site Response Analyses), site-specific response analyses were performed at more than 300 domestic sites. In this study, a new site classification system and design response spectra are proposed using results of the site-specific response analyses. Depth to bedrock (H) and average shear wave velocity of soil above the bedrock ($V_{S,Soil}$) were adopted as parameters to classify the sites into sub-categories because these two factors mostly affect site amplification, especially for shallow bedrock region. The 20 m of depth to bedrock was selected as the initial parameter for site classification based on the trend of site coefficients obtained from the site-specific response analyses. The sites having less than 20 m of depth to bedrock (H1 sites) are sub-divided into two site classes using 260 m/s of $V_{S,Soil}$ while the sites having greater than 20 m of depth to bedrock (H2 sites) are sub-divided into two site classes at $V_{S,Soil}$ equal to 180 m/s. The integration interval of 0.4 ~ 1.5 sec period range was adopted to calculate the long-period site coefficients ($F_v$) for reflecting the amplification characteristics of Korean geological condition. In addition, the frequency distribution of depth to bedrock reported for Korean sites was also considered in calculating the site coefficients for H2 sites to incorporate sites having greater than 30 m of depth to bedrock. The relationships between the site coefficients and rock shaking intensity were proposed and then subsequently compared with the site coefficients of similar site classes suggested in other codes.

• Wind and Structures
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• 제25권2호
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• pp.195-214
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• 2017

Full-scale wind characteristics based on the field measurements is an essential element in structural wind engineering. Statistical analysis of the wind characteristics at Sutong Cable-stayed Bridge (SCB) site is conducted in this study with the recorded long-term wind data from structural health monitoring system (SHMS) between 2008 and 2015. Both the mean and turbulent wind characteristics and power spectra are comprehensively investigated and compared with those in the current codes of practice, such as the measured wind rose diagram, monthly maximum mean wind speed, turbulence intensity, integral length scale. Measurement results based on the monitoring data show that winds surrounding the SCB site are substantially influenced by the southeast monsoon in summer and strong northern wind in winter. The measured turbulence intensity is slightly higher than the recommended values in specifications, while the measured ratio of lateral to longitudinal turbulence intensity is slightly lower. An approximately linear relationship between the measured turbulence intensities and gust factors is obtained. The mean value of the turbulence integral length scale is smaller than that of typical typhoon events. In addition, it is found that the Kaimal spectrum is suitable to be adopted as the power spectrum for longitudinal wind component at the SCB site. This contribution would provide important wind characteristic references for the wind performance evaluation of SCB and other civil infrastructures in adjacent regions.

• 한국조리학회지
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• 제21권1호
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• pp.159-173
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• 2015

본 연구는 SNS를 활용하여 자신의 이용목적에 부합하는 외식업체에 관한 정보를 확인하거나, 혹은 자신이 이용하고 싶은 외식업체에 관한 정보를 수집하고자하는 소비자를 대상으로 SNS 정보의 특성, SNS 사이트 특성, 정보유용성 그리고 방문의도 간의 영향관계를 확인하고자 하였다. 연구목적을 달성하기 위해 SNS 정보특성, SNS 사이트특성, 정보 유용성, 방문의도에 관하여 문헌고찰을 진행하였으며, 가설검정을 위해 실증 조사분석을 실시하였다. 분석결과는 다음과 같다. 1) SNS 정보특성인 정보의 신뢰성, 유희성, 중립성 요인은 정보유용성지각에 유의한 영향을 미치는 것으로 나타났으며, 특히 정보의 중립성요인이 상대적으로 높은 영향력을 미치는 것으로 나타났다. 2) SNS 사이트특성인 상호작용성, 이용용이성, 사이트신뢰성요인은 정보유용성지각에 유의한 영향을 미치는 것으로 나타났다. 특히 SNS 사이트 특성요인 중 상호작용성 요인이 상대적으로 높은 영향력을 미치는 것으로 나타났다. 3) SNS 사용자가 지각하는 정보유용성이 해당 업체의 방문의도에 미치는 영향관계를 확인한 결과, 유의한 영향을 미치는 것으로 나타났다.

• 한국산림과학회지
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• 제94권1호통권158호
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• pp.26-33
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• 2005

본 연구는 강원도 평창 지역의 천연 활엽수림을 대상으로 입지유형별 임분의 생장 특성과 생태적 특성을 구명함으로써 각 임분 특성에 맞는 산림관리 방안을 제시하고자 하였다. 이를 위해 연구 대상지를 방위, 해발고도, 지형 조건에 따라 36개의 입지유형으로 구분하고 각 입지유형별로 직경 생장량과 직경 생장률 그리고 Shannon-Wither의 다양성지수, 균재도, 풍부도를 파악하여 임분의 생장 특성과 생태적 특성을 비교 분석하였으며, 이를 근거로 산림관리 방안을 제시하였다. 임분의 생장 특성은 방위에 따라서는 동쪽 사면과 서쪽 사면이, 해발고도에 따라서는 서쪽 사면을 제외하고는 해발고도가 낮아짐에 따라, 그리고 지형 조건에 따라서는 사면과 계곡이 양호한 생장 상태를 유지하고 있었다. 생태적 특성은 적정한 습도 조건을 유지할 수 있는 지역으로 방위별로는 북쪽 사면과 서쪽 사면, 지형 조건별로는 계곡의 종 다양성이 높게 나타난 반면 해발고도에 따른 일정한 경향은 찾아볼 수 없었다. 입지유형별 산림관리 방안은 남쪽 사면과 동쪽 사면의 경우 임목 생장과 생태적 특성을 함께 고려한 무육작업이 필요한 반면 서쪽 사면과 북쪽 사면은 생장 촉진을 위주로 한 밀도조절이 필요한 것으로 파악되었다. 해발고도에 따라서는 저지대는 생태적 특성을 고려한 무육관리가 필요하며, 고지대와 중지대는 직경 생장률이 2% 미만인 지역에 대해서는 생장 촉진을 위한 무육작업이 시급한 것으로 나타났다. 한편 지형 조건에 따라서는 남쪽 사면의 중지대와 고지대를 제외하고는 계곡의 생태적 안정성이 기장 양호한 것으로 나타나 친환경적 경영에 가장 적합한 지역으로 평가되었다.

• Structural Engineering and Mechanics
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• 제60권3호
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• pp.433-453
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• 2016

During earthquake, the motion of ground is affected significantly by source characteristics, source-to-site path properties and local site conditions. Due to the influence of local soil conditions different places experience distinctive amplitude of surface ground motion. Ground response analysis of a specific site utilizing the borehole information at different locations is done in present study. The ground motion with the highest peak ground acceleration for this site obtained from the ground response analysis is used in finite element soil-structure interaction analysis of multi-storey shear wall buildings with various positions of shear walls. The variation in seismic response of buildings and advantageous position of shear wall are determined. The study reveals that providing shear wall at the core of buildings at the specific site is advantageous among all shear wall configurations considered.