• 대한전자공학회논문지SP
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• 제37권1호
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• pp.83-89
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• 2000

기지국에서 안테나 배열을 쓰면 간섭효과가 줄어들어 공간적으로 선택적인 정보를 보내고 받을 수 있다 이 논문에서는 이동국 근처에서 국소적으로 산란된 신화의 새로운 모형을 제시하고, 이 모형에서 빔형성기의 가중값을 얻는다. 모의실험결과는 제안한 방법의 성능이 매우 뛰어나고, 따라서 각 퍼짐이 넓고 여러길 전파가 심한 도시 환경에 제안한 방법이 알맞음을 보여준다.

• 상하수도학회지
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• 제28권1호
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• pp.111-124
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• 2014

Decentralized water supply systems, treating the water in users'vicinity, cutting down the distribution system, utilizing the alternative water resources(rainwater harvesting, water reclamation and reuse and so on.) and saving energy and other resources, could be categorized into POU(Point-Of-Use), POE(Point-Of-Entry) and community small scale system. From the literature review, we could thought that decentralized water supply system and hybrid system(integrating centralized and decentralized water supply system within urban water management) might have strengthening comparative advantages to centralized system with respect to: (1) water security, (2) sustainability, (3) economical affordability. Even though it is difficult to derive and quantify direct benefit advantages from decentralized and hybrid system in comparison with centralized system, (1) operational cost reduction, (2) assurance for safe and stability water supply and (3) greenhouse gas reduction can be expected from successful establishment of the former.

• 한국주거학회논문집
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• 제8권3호
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• pp.81-90
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• 1997

Cheju province exposes a separated residential culture compared to the mainland area. since it has its own unique climate, natural features. Therefore, this study tried to grasp the residential behavior. was based on the questionnaire to Cheju province people, using the approach by statistic verification. This study also focused and aimed on suggesting the basic data about housing plan which is appropriate to the climate. natural features requirement from inhabitants through the comparison and analysis between the mainland area and Cheju province. The results of the study are as follows; Firstly. the diversified applicative study on ‘Ol-rae’. ‘Ma-dang’, ‘Yoo-young’ and so forth that is traditional outside garden of Cheju is imperative, because in urban area people think traffics, vicinity, etc. are more significant, and in rural area people think occupying large outside space is more significant. Secondly. in the study of the degree of satisfaction on the housing, most of the people's was ‘neutral’ and in rural area quite a lot of negative reaction exposed. This is owing to the uniform introduction on residential style of the mainland area. Thirdly, housing plan should be considered family members' housing needs and provincial characteristics, meanwhile most of the people answered positively about the residential value which is considered very significant lately, for instance, security of privacy. appropriate plan for child's room.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.1026-1031
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• 2003

Numbers of people living in high rise apartments are growing due to the overcrowding in urban area. Acoustic environment in those residential buildings has been seriously deteriorated by the increase of wheeled transports. Commonly used sound barriers have a limitation in controlling noise influencing higher part of a residential building. The use of noise barrier tunnels can be an alternative to supplement the defects of conventional noise barriers. But intensive measurements on noise levels at apartments vicinity of current noise barrier tunnels show that the tunnel now has a limited advantage on reducing the noise levels from arterial roads. The present work aims at providing an useful design tool In designing noise barrier tunnels for residential areas adjacent to roads. Number of field measurements, scale model measurements, and computer simulations were performed to ensure whether the prediction from scale model and computer simulation are appropriate. Result shows that the predictions from scale models and computer simulations could be valid prediction tools for designing sound barrier tunnels.

• Ecology and Resilient Infrastructure
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• 제6권3호
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• pp.137-144
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• 2019

본 연구는 수공구조물 주변에서 발생하는 폭기 흐름의 기포분율을 측정하는 실험 연구를 수행하였다. 그림자기법을 이용한 영상측정기법을 적용하여 기포분율을 측정하고 이를 통해 폭기 정도를 정량화하였다. 제안된 영상기법을 이용하여 경사보와 계단보 주변에서 발생하는 흐름을 측정하였다. 흑백 영상으로부터 얻어진 공간적으로 분포한 기포분율은 친환경 수공구조물 주변에서 폭기 정도를 제시할 수 있었다. 얻어진 결과로부터 계단보의 전면경사부와 하류부에서 상대적으로 강한 폭기 현상이 발생함을 알 수 있었다.

• Geomechanics and Engineering
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• 제29권3호
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• pp.339-348
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• 2022

The bored tunneling method is generally preferred for urban tunnel construction, However the cut & cover tunnel is still necessary for special conditions, such as metro station and access structures. In some case, deep excavation for cut & cover construction is planed of irregular and unusual shape, as a consequence, the convex and concave corner is often encountered during that excavation. In particular, discontinuity or imbalance of the support structure in the convex corner can lead to collapse, which may result in damages and casualties. In this study, the behavior of the convex corner of retaining structure were investigated using 3-dimensional numerical models established to be able to simulate the split-shaped behavior of convex corners. To improve the stability in the vicinity of the convex corner, several stabilizing measures were proposed and estimated numerically. It is found that linking two discretized wales at the convex corner can effectively perform the control of deformation. Furthermore, it was also confirmed that the stabilizing measures can be enhanced when the tie-material linking two discretized wales is installed at the depth of the maximum wall deflection.

• 자원환경지질
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• 제38권2호
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• pp.135-142
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• 2005

도곡광산 주변지역 중금속 원소들의 오염 특성을 알아보고, 이들 원소들의 생체흡수도를 평가하기 위해서 본 연구를 수행하였다. 연구 대상 지역의 주오염원은 광미 및 폐석더미 그리고 갱내수 등으로 추정된다. 광미 내에는 As이 $140{\cal}mg/{\cal}kg$, Cd이 $107{\cal}mg/{\cal}kg$, Cu가 $3017{\cal}mg/{\cal}kg$, Pb가 $12926{\cal}mg/{\cal}kg$, Zn는 $9094{\cal}mg/{\cal}kg$(우기 전 시료)로 높은 함량을 나타내고 있다. 밭토양 내의 중금속 원소들 함량은 자연토양 내의 평균함량(Bowen, 1979)보다 높게 나타났으나, 광미적치장의 광미에 비해서 낮은 함량을 나타낸다. 수계내 중금속 함량은 독성 원소들의 주오염원으로 생각되는 본 갱의 광미적치장 주변 하천수 시료에서 가장 높은 수준을 나타내었고, 하류로 가면서 희석 효과에 의해서 그 함량이 점차 감소하는 경향을 나타내고 있다. 광미와 토양을 대상으로 연속추출분석을 한 결과, 비잔류상 형태의 존재비율이 높게 나타났는데 이는 계속적인 풍화와 산화에 의한 오염을 지시한다. 그리고 Cd과 Zn는 대상 지역 대부분에서 높은 이동도를 나타내고 있다. 밭토양을 대상으로 SBET분석에 의한 중금속 원소들의 생체흡수도 평가 결과, $Cd(55.3\%),\;Cu(46.5\%),\;Zn(41.0\%),\;As(37.0\%)$로 나타났다. 밭토양(S3) 시료는 중금속 원소들의 총 함량과 생체흡수도 모두 가장 높은 함량을 나타내었다.

• 한국환경생태학회지
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• 제22권6호
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• pp.691-706
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• 2008

본 연구에서는 해안 매립도시인 안산시 철도변 완충녹지를 대상으로 완충녹지의 문제점을 분석하고, 완충녹지의 공간기능과 식재개념에 적합한 식재방안을 제시하였다. 안산시 철도별 완충녹지의 식재밀도는 $0.04{\sim}0.17$주/$m^2$ 이었고, 녹지용적계수는 $0.15{\sim}1.65m^3/m^2$로 녹량이 부족하여 완충기능이 미흡하였다. 마운딩 완충녹지의 토양경도는 $2.72{\sim}15kg/cm^2$로 식생생육에 적합하지 않았다. 완충녹지의 기능을 향상시키기 위해 야생조류 서식 측면의 생물서식기능, 주변 토지이용 측면의 도시공원기능, 식재수종 계절성 측면의 경관개선기능을 검토하였다. 완충녹지를 기능에 따라 생물서식기능의 완충녹지, 완충 및 경관개선기능의 완충녹지, 경관 및 도시공원기능의 완충녹지, 완충 및 생물서식기능의 완충녹지로 재설정하였다. 완충기능 식재방안에서는 곰솔 등을 주요종으로 선정하고, 교목종 0.4주/$m^2$, 관목종 0.5주/$m^2$로 식재밀도를 설정하였고, 경관개선 기능에서는 느티나무, 산벚나무, 살구나무 등을 주요종으로 선정하고 교목종 0.2주/$m^2$, 관목종 0.5주/$m^2$로 식재밀도를 설정하였다. 생물서식기능에서는 상수리나무, 산벚나무, 팥배나무 등을 주요종으로 선정하고, 적정 식재 밀도를 교목종 0.06주/$m^2$, 아교목종 0.1주/$m^2$, 관목종 0.8주/$m^2$로 식재밀도를 제시하였다.

• Current Research on Agriculture and Life Sciences
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• 제24권
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• pp.37-42
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• 2006

The purpose of this study was a biota research and analysis for Close-to-nature stream restoration planning of Shinchun. The summary of this study is as follows; 1) The vascular plants in research area recorded of 45 species and insect fauna recorded of 34 species of 8 orders. As a result of table of community classification, the communities were two group; Quercus variabilis community(I), Pinus densiflora-Quercus variabilis-Quercus dentata community(II). 2) As a result of analysis on correlation of tree species, the level of significance in positive correlation between Quercus dentata and Corylus heterophyll aindicated 1% and between Pinus densiflora and Lespedeza bicolor also indicated 1%. 3) As a result of DBH analysis, it is expected that Quercus variabilis and Quercus dentata will dominateover other species in competition and its succession continuously maintains from now on in community I. In community II, it is assumed that there is a high possibility of changing into community of Quercus such as Quercus mongolica, Quercus dentata, and Quercus variabilis. 4) As a result of analysis on insect fauna, insect fauna consists of 94% of whole species as 32 species, 23 families, 8 orders. And 7 species, 7 families 4 orders was found in highly urbanized area, the vicinity of Sang-Dong bridge. 5) As mentioned above, Based on A biota fundamental research, Close-to-nature stream restoration planning were full of suggestions: i) Designating ecosystem preservation area, ii) Making Close-to-nature stream revetments, iii) Making pool-and-riffle, vi) Making decks for observation and walks for nature experience, v) Creating wetland biotope. Through these methods, it is necessary to promote bio-diversity and lead people to the space for eco-learning.

• 대한지역사회영양학회지
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• 제6권3호
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• pp.516-526
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• 2001

Working towards the compression of morbidity, we attempted to find the way to contribute to desirable aging and/or healthy old age. By looking into the factors affecting nutrient intake in middle-aged adults, we sought to find ways to improve their health status, Two hundred and fifty middle-aged adults from 40 to 60 years of age residing in Seoul and its vicinity were recruited for the survey. Subjects were interviewed for general characteristics, dietary habits lifestyle, status and food intake by a trained interviewer. Two -day food record was included in addition to the 1 -day 24 hr recall. Date were analyzed for the relationship among nutrient intake, health status, socio-economic status dietary habits and lifestyle using a statistical program (SAS) Although the mean energy intake of the subjects did not reach the recommenced dietary allowances(RDA), mean protein intake was well above the RAD for both sex groups(111.2% and 129.1% for men and women, respectively) The caloric contribution of fat was 15 to 20 % of total energy intake among different groups. Riboflavin was the most deficient nutrient and its mean intake reached only 71.0% of RDA for mean This seemed to be due to the lower intake of milk and dairy products among middle-aged Koreans who are more accustomed to traditional meals. Income and exercise habit were the most important factors influencing the nutrient intake of middle-age adults. Also, BMI, smoking habit, level of education regularity of meal, and hours of sleeping influenced the nutrient intake, In conclusion, middle-age adults appeared to have similar problems with the elderly in terms of nutrient intake and this age group should to included when considering nutritionally vulnerable groups in addition to the elderly and young children. The improvement in the nutrition status of middle-age adults is even more important because that could lead into the better health the elderly.