• Macromolecular Research
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• 제16권5호
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• pp.404-410
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• 2008

In order to obtain 'value added products' from polypropylene (PP)/waste ground rubber tire powder (WGRT) composites, PP/WGRT microcellular foams were prepared via supercritical carbon dioxide. The effects of blend composition and processing condition on the cell size, cell density and relative density of PP/WGRT micro-cellular composites were studied. The results indicated that the microcellular structure was dependent on blend composition and processing condition. An increased content of waste ground rubber tire powder (WGRT) and maleic anhydride-grafted styrene-ethylene-butylene-styrene (SEBS-g-MA) reduced the cell size, and raised the cell density and relative density, whereas a higher saturation pressure increased the cell size, and reduced the cell density and relative density. With increasing saturation temperature, the cell size increased and the relative density decreased, whereas the cell density initially increased and then decreased.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.170-175
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• 2009

Apartment housing block has been spreaded according to rapid economic development and urbanization in Korea. A parking lot is located at underground, artificial ground is inevitably created in apartment housing block. Artificial ground creates different thermal environment compared to natural ground, because the composition and coverage of artificial ground are diverse. In this study, the effect of the artificial ground on building thermal environment will be disscussed by simulation. Considering the result of simulation, surface albedo is more important for building energy performance. A purpose of this study is to examine how the characteristic of surface effect to thermal environment, and to develop design method for sustainable outdoor space.

• 교육시설 논문지
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• 제18권6호
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• pp.33-43
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• 2011

The Korean academics of classical learning, Seowon which from the middle of Joseon Dynasty was complexly reflected in "the illustration of Taiji(太極圖說)" Five-Elements school(陰陽五行說), "Zhou Yi(周易)" and a theory on spherical heaven and square ground(天圓地方) which based on orientalism. Also the theory of Xiangshu Xue(象數學) was a significant factor to decide the size(number of facade module) of Seowon architecture. So, in this study, how the oriental thought was adopted and reflected in existing 21 Seowon in South Korea. The size of Seowon architecture was adopted a theory of combination with heaven, earth and human(天地人三合論) that based on the theory of Xiangshu Xue on "the illustration of Taiji" and "Zhou Yi". "Zhou Yi" was the central thought of Confucian culture in Joseon Dynasty, with which Seowon space was divided into two, ancestral rites space and lecture space. It coincides with balance of yin(陰) and yang(陽), Five-Elements(五行) and four seasons(四季節). In lecture space, lecture hall is relevant with the water(水) and winter, and front tower structure or outer three-door is the fire(火) and summer. Also, central garden means the soil(土) and center. Thus, the size and spatial composition was planned with the philosophy, "the illustration of Taiji", Five-Elements school and a theory on spherical heaven and square ground. Yin and yang has an idea of the heaven and earth, and Five-Elements has an idea of direction and season with which spatial composition of Seowon could be set. And the numeral meaning on the theory of Xiangshu Xue established an ideal background for spatial composition of Seowon architecture.

• 교육녹색환경연구
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• 제13권1호
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• pp.75-85
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• 2014

In this study, the characteristics and the composition of the school groundrevels in Korea to identify the problem, were compared with Japan, where in geographic and culturally similar environment the composition of the school groundrevels analyzed. The spatial extent of this study is the development of metropolitan areas and small city within 10 years (range time) survey of the 34 elementary schools were analyzed. The results are as follows: First, the school groundrevels are flat step-like form of the composition for the same level of barrier-free should be provided. Second, if the lower places in slopes where to place buildings and playgrounds are placed in high places. Third, the external space and the interior space of the connection is the concept of fault tolerance and eliminate need for stairs. This study is a part of the urban Newtown and there are limitations to generalize the results. Therefore, this result on the general guidance of school groundrevel composition in order to objectify an additional studies are required.

• 한국태양에너지학회 논문집
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• 제29권5호
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• pp.88-97
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• 2009

In these days, it attracts our attention to create a green outdoor environment around the building block in urban area. Green space and permeable ground covering are increased by laws and regulations. According to these trends, variety researches for improving outdoor environment are accomplished at this moment. However, the problems for outdoor environment such as heat island effect and air contaminant in urban area are still reported. The purpose of this study is to examine the variables to affect the formation of outdoor thermal environment by quantitative analysis. As a initial study, in this paper, the effect of ground composition on changes of surface temperature and heat flux in multi-residential building were analyzed by field measurement and numerical simulation. Through field measurement, the surface temperature and heat flux of artificial ground in multi-residential building in Suwon city were measured. The result showed that the surface temperature was decreased by about $20^{\circ}C$ with afforestation of artificial ground compared with those of concrete covering. Moreover, the inner temperature of artificial ground was changed as same behaviors of outdoor temperature changes to depths of 20cm. In simulation, the effect of soil types and depth of artificial ground on the changes of the surface temperature and heat flux were analyzed. As results, the natural soil ground was more effective against lowering the surface temperature than any other cases in the analyzed cases.

• Journal of Ecology and Environment
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• 제31권4호
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• pp.297-307
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• 2008

In order to assess the effect of grazing on grasslands using floristic composition, we studied the floristic composition and plant biomass of steppe vegetation in Hulunbeier, Inner Mongolia. The dominant species of the grasslands were Stipa krylovii, Stipa grandis and Leymus chinensis. Floristic composition changed according to grazing pressure, being light, heavy and moderate. Under heavy grazing conditions, the importance value of P. acaulis, C. korshinskyi and Cleistogenes squarrosa increased in the plant community. These species were indicators of heavily grazed stand. Plant biomass of the stands ranged within 11.6g $m^{-2}$ and 63.5g $m^{-2}$ and 69.5g $m^{-2}$ and 166.2g $m^{-2}$ to the west and east of Lake Hulun, respectively. These values are equivalent to ca. $450{\sim}1,000kg$ of atmospheric carbon per hector, which is retained within the stand during the summer season.

• 생태와환경
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• 제44권1호
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• pp.42-57
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• 2011

We described the above-ground plant species composition and measured a range of soil physico-chemical properties and the composition and size of the soil seed bank in the remnant natural vegetations on the flood plains of the Han River within Seoul, South Korea. We used analysis of variance and multivariate analyses to analyse the data and S${\o}$rensen's similarity index to compare the composition of the vegetation and seed banks. The soils were circum-neutral and composed of mainly sand and silt fractions with a very limited clay component; a gradient based on sand/clay proportions was identified. The soil seed banks varied markedly between- and within-sites and had much greater species diversity than the above-ground vegetation. Two of the major dominants in the vegetation (Miscanthus saccariflorus and Phragmites australis) were found at very low densities in the seed bank. The site differences appeared to be correlated with the sand-clay gradient, suggesting that the soil properties differentially affected seed inputs into the soil, or that the processes than controlled sediment deposition during floods was also important in differentially affecting seed deposition. Lastly, there was relatively little similarity between the vegetation, dominated mainly by perennials, and the seed bank which contained a relatively large proportion of annuals and biennials. This result suggests that after disturbance caused by flooding there is the potential for many other species to colonize. This may impinge on the regeneration potential of the sites and cause concern for the future conservation of these important remnants of natural vegetation.

• Asian-Australasian Journal of Animal Sciences
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• 제19권1호
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• pp.31-34
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• 2006

The experiment was conducted to determine the effects of cutting interval and cutting height on the yield and nutrient composition of hedge lucerne (Desmanthus virgatus) when grown on a sandy soil in the Northeast of Thailand. The cutting intervals compared were 30, 40 and 50 days between harvests and the cutting heights 30, 40 and 50 cm above ground level. The experiment was a $3{\times}3$ factorial layout in a randomized complete block design with 4 replications-giving a total of 36 plots each $3{\times}3m^2$. Harvested plant material was weighed, dried and the ground subsamples taken for analyses of crude protein (CP), crude fiber (CF), ash, ether extract (EE) and nitrogen-free extract (NFE). At the last harvest the hedge lucerne samples were separated to determine leaf to stem ratios and then analyzed for nutrient composition in the leaf and stem. Results showed that increasing the cutting interval (i.e. advancing age of maturity) increased dry matter and nutrient yields significantly. In terms of nutrient content, it also increased the crude fiber, ash, ether extract and nitrogen free extract percent in the plant. However, crude protein percent was markedly decreased as the cutting interval increased. Increasing cutting height had no effect on dry matter yield and yields of nutrients, but in terms of nutrient content, it increased crude protein and ash content, but decreased crude fiber content. The percent EE and NFE in the plant was unaffected by cutting height. From the results presented it is clear that cutting a stand of hedge lucerne every 40 to 50 days will achieve greater dry matter and nutrient yields than cutting more frequently, at 30 days. The cutting height at harvest, whether 30, 40 or 50 cm above ground level had no effect on dry matter or nutrient yields of hedge Lucerne. Hedge lucerne therefore offers the Thai poultry farmer a useful alternative protein supplement for poultry diets rather than relying on the more expensive soybean meal. As it can be readily and successfully grown on a range of soil types and climates throughout Thailand, hedge lucerne also offers the Thai farmer a valuable additional source of income.

• 한국터널지하공간학회 논문집
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• 제21권3호
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• pp.323-345
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• 2019

토사지반과 핵석지반에서 EPB 쉴드 TBM을 통한 성공적인 터널 시공을 위해서 굴착면 전방의 지반 정보를 정확히 파악하는 것이 필요하다. 본 연구에서는 전기비저항 탐사와 유도분극(induced polarization) 탐사를 함께 활용하여 복합토사지반과 핵석지반에 대한 전방 예측 방안을 제시하고자 하였다. 토사지반의 구성은 EPB 쉴드 TBM에서 첨가재 선택에 필수요소이며, 핵석지반은 기계화 시공에서 난이도가 높은 지반이기 때문이다. 탐사는 TBM이 굴진을 멈추고 세그먼트 1링을 조립할 시에 커터헤드에 설치된 4개의 전극을 활용하여 수행된다고 보았다. 토사지반의 경우 화강풍화토, 모래, 점토로 구성된 복합지반에 대해 축소모사하여 실내실험을 수행하였다. 실험 결과 전기비저항은 복합지반 이론해와 상당히 일치하였으며 유도분극은 경우에 따라 전기비저항과 경향성이 일치하거나 완전히 상반되었다. 이러한 결과를 토대로 실제 현장에서 적용 가능한 토사지반 예측방안을 제시하였다. 핵석지반의 경우 균질지반에서 핵석지반으로 굴착해 나가는 상황을 축소모사하였으며 핵석의 불규칙성을 난수를 통해 모사하였다. 실험결과 전기비저항은 핵석지반에 접근할수록 증가하였고 유도분극은 불규칙하게 오르내림을 거듭하는 경향을 나타내었다.

• 대한한의학회지
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• 제22권4호
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• pp.114-120
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• 2001

Objectives : Man adapts himself to nature, so accordingly as he grows up, changes of body composition appear. This study measured the changes of body compositions on the ground of Sasang constitution and seasons Methods : 253 middle school students who live in Busan were studied from the 20th of March, 1999 to the 20th of March, 2001. We measured height and body compositions with Inbody 3.0, six times during that period. Results : According as they grew up, total body water, muscle area, body weight, BMI (Body Mass Index), BMR (Basal Metabolic Rate), ACM (Arm Muscle Circumference), and BCM (Body Cell Mass) increased, but fat body weight ratio decreased. From March to June, total body water, muscle area, height, ACM, and BCM increased. From September to December fat body weight, fat body weight ratio, waist hip ratio increased as compared with other seasons. Height of Soyangin and BMI of both Soyangin and Taeumin increased more than those of other groups, with statistical significance Conclusions : The growth of man is adapting oneself to changes of nature, and it corresponds to the theory of (correspondence between man and universe).