• Journal of the Korean Wood Science and Technology
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• 제44권2호
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• pp.283-293
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• 2016

Owing to an increase in the air tightness of recent buildings, the natural ventilation rate was significantly lowered and the removal of accumulated moisture became difficult in these buildings. The hygrothermal performance of these buildings should be carefully considered to provide comfortable indoor environment by removing the moisture condensation risk and the mold growth potential. In this study, hygrothermal performance of two selected wall structures was investigated based on WUFI simulation program. The results displayed that the indoor temperature had impact on the moisture accumulation in the insulation layer for both modeled walls, showing that lower indoor temperature resulted in higher moisture accumulation, especially in the wood frame structure. Also, the yearly moisture accumulation profile exhibited a downward shift throughout the year by adding a vapour retarder with a lower sd-value. In addition, both of the two walls have condensation risk in winter, due to low temperature level. The wood frame structure has a bigger fluctuation and higher condensation risk than the concrete structure.

• Journal of the Korean Wood Science and Technology
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• 제38권1호
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• pp.56-65
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• 2010

본 연구는 외기에 노출된 경골목조벽체의 수분축적을 감소시킬 수 있는 벽체 구성을 찾기 위해 수행되었다. 이를 위해 다음 다섯 가지 형태의 벽체 구성을 대상으로 벽체 내 수분이동과 수분축적을 평가하였다; 일반적인 벽체구성(기본벽체 T), 실내 측 방습지 추가(P1), 실내 측과 단열재 구간의 방습지 추가(P2), 환기를 위한 사이딩 뒷면의 공기층 추가(P3), P3벽체에서 실외 측 방습지의 실내 측으로 이동(P4). 옥외 실험가옥에 기본벽체와 제안벽체를 설치하여 외기에 노출된 벽체의 수분이동과 수분축적을 평가하였다. 실험결과 계절에 따라 추가 방습지와 공기층의 개선 정도가 다르게 나타났으나 연간 벽체 내 수분축적 감소에 유리한 벽체 구성은 1) 공기층 추가 및 실내 측으로 방습지 이동(P4), 2) 실내 측 방습지 추가(P1), 3) 기본벽체(T), 4) 공기층 추가(P3), 5) 실내 측 및 단열재 구간 방습지 추가(P2) 순으로 나타났다.

• Journal of Electrical Engineering and Technology
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• 제10권3호
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• pp.1124-1130
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• 2015

Moisture and high temperature are the most important factors that lead to the ageing of oil-paper insulation, but the research about space charge characteristics of oil-paper insulation does not take the combined effect of ambient temperature, moisture and thermal ageing into account. The pulsed electroacoustic (PEA) method was used to investigate the influence of moisture and temperature on space charge characteristics of oil paper at different ageing stages. The results showed that moisture could speed up formation of space charge in oil paper when water concentration was low, but the formation was restrained if the water concentration was high. At the beginning of thermal ageing, heterogeneous charge accumulation had predominance, but it gradually changed to homogeneous charge injection with ageing. It was believed that moisture concentration could speed up ageing and enhance charge accumulation on one hand, and accelerate or slow down the establishment speed of space charge on the other hand, therefore, charge accumulation type changed with ageing. The more seriously the oil-paper insulation was thermally aged, the deeper the trap energy level was, hence more space charge was trapped, which could be speeded up by increasing the ageing temperature, but the effect of ambient temperature did not fit the Arrhenius law.

• Journal of the Korean Wood Science and Technology
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• 제37권4호
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• pp.320-329
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• 2009

본 연구는 경골목조벽체의 구조적 안전성을 위협하고 주거환경을 열악하게 하는 벽체 내 수분축적을 감소시키기 위해 수행되었다. 이를 위해 벽체 구성 요소를 변화시켜 실험을 진행하였다. 벽체 구성요소는 방습지 및 공기층을 추가하였고, 이들의 변화에 따른 수분이동의 변화를 조사하기 위하여 실내외 온습도 차이가 뚜렷한 가혹조건에서 기본벽체와 제안벽체의 비교실험을 진행하였다. 실험결과 실내 측 방습지 추가로 방습성능을 높이는 것은 실내로부터의 수분이동 감소에 효과적으로 나타났지만 두 개의 방습지를 설치하는 경우 과도한 방습 성능이나 부적절한 위치선정으로 벽체의 내부의 상대습도를 높이는 것으로 나타났다. 공기층 추가는 환기 효과에 의해 벽체 내부에서 실외로 수분이동을 야기하였다. 공기층에 의해 실내로부터 벽체 내부로 유입되는 수분이동을 막을 대안을 찾는다면 환기에 의한 벽체 내 수분감소 효과를 극대화 할 수 있을 것으로 기대된다.

• 한국의류학회지
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• 제25권1호
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• pp.61-70
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• 2001

As important factors determining human sensorial comfort, liquid moisture management and surface properties of heat resistant workwear materials were examined. To figure out liquid moisture management properties of the test materials, absorption capacity, rate of absorption, and evaporation properties were assessed. A modified GATS(Gravimetric Absorbency Testing System) was used to measure the liquid moisture accumulation associated with the wicking of liquid moisture from sweating skin. The GATS procedure measures demand wettability of materials to take up liquid in a direction perpendicular to the fabric surface and it was modified to incorporate a special test cell and cover to assess absorption behavior in the presence of evaporation. Fabric stiffness, smoothness, number and the length of surface fibers, and an estimate of the contact area between the skin and fabric surface were measured to characterize the mechanical and surface properties of the test materials. Also an estimate of the force with which a fabric clings to moist skin was made using as wet-cling index.

• 한국초지조사료학회지
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• 제5권2호
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• pp.152-161
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• 1985

생육기간중(生育期間中) 토양수분함량(土壤水分含量)의 차이(差異)가 수수속작물(屬作物)의 건물생산(乾物生産)과 성분함량(成分含量)에 미치는 영향을 알기 위하여 공시작물(供試作物) 및 품종(品種)으로 수수의 Pioneer 931, 수수${\times}$수단그라스교잡종(交雜種)의 Pioneer 988, 수단그라스의 Piper 및 옥수수의 수원(水原)19호(號)를 공시(供試)하였으며, 토양수분함량(土壤水分含量)은 포장용수량(圃場容水量)의 100, 80, 60 및 40%로 유지(維持)하며 시험(試驗)을 실시(實施)하였는바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 주당건물수량(株當乾物收量)은 토양수분(土壤水分) 60%에서 각각(各各) Pioneer 931, 176.2g, Pioneer 988, 180.8g 및 옥수수 164.0g으로 가장 높았다. 2 토양수분함량(土壤水分含量).에 따른 생육시기별(生育時期別) 건물축적량(乾物畜積量)은 수단그라스를 제외(除外)하고는 각작물(各作物)에서 공히 60>40>80>100%수분구(水分區)의 순(順)이었다. 3. 절대생장율(絶對生長率)(AGR)은 각품종(各品種) 모두 60% 수분구(水分區)에서 가장 높았으나 수단그라스는 80% 수분구(水分區)에서 높았다. 상대생장율(相對生長率)(RGR)은 각품종 모두 생육초기(生育初期)에 높고 생육후기(生育後期)에는 낮았으며, 순동화율(純同化率)(NAR)은 6월(月)29일(日)${\sim}$7월(月)5일(日) 기간중(期間中) 60% 토양수분구(土壤水分區)에서 $72{\sim}467g/m^2$/일(日)으로 가장 높았다. 4. 건엽중(乾葉中)의 조섬유함량(粗纖維含量)은 Pioneer 931의 경우 100% 및 80%수분구(水分區)($28.6{\sim}28.8%$)에서 높고 60 및 40%수분구(水分區)($23.6{\sim}24.1%$)에서 낮은 편이었다. 그러나 옥수수의 조섬유함량(粗纖維含量)에 따라 큰 차이(差異)가 없었다. 건엽(乾葉)의 조단백질함량(粗蛋白質含量)에 따라 큰 차이(差異)가 없었다. 건엽(乾葉)의 조단백질함량(粗蛋白質含量)은 60%수분구(水分區)($14.2{\sim}21.6%$) 및 40%수분구(水分區)($13.8{\sim}16.0%$)가 다른 고토양수분구(高土壤水分區)($7.3{\sim}13.9%$)보다 높은 편이었다. 5. 건경중(乾莖中)의 조섬유함량(粗纖維含量)은 $24.6{\sim}36.7%$로서 건엽중(乾葉中)의 함량(含量)보다 월등히 높았고 조단백질함량(粗蛋白質含量)은 $2.0{\sim}5.3%$로서 건엽중(乾葉中)의 함량(含量)보다 현저히 낮았다. 특(特)히 P.931의 건경중(乾莖中)의 조섬유함량(粗纖維含量)은 다른 작물(作物)에 비해 현저(顯著)히 높은 편이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권3호
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• pp.346-350
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• 2001

The present study was designed to evaluate the usefulness of Sauropus. androgynus leaf (SAL) meal on reducing fat accumulation in broiler chickens. Eighty unsexed broiler chickens were allocated to four treatment groups with five replicates of four chickens each. SAL meal supplementation had no effect on body, leg, back, breast, wing, liver and heart weights, carcass protein, moisture and ash contents (p>0.05). Broilers fed diets supplemented with 30 g of SAL meal had lower feed intake with better feed conversion ratio (p<0.05) than did the control chickens. SAL supplementation at all levels significantly reduced fat accumulation in abdomen region, and liver (p<0.01), and in carcass (p<0.05). Higher SAL supplementation resulted in lower fat accumulation in the carcass ($r^{2}=0.94$; p<0.01), abdomen ($r^{2}=0.99$; p<0.01) and liver ($r^{2}=0.98$; p<0.01). The current study showed that a 30 g supplementation of SAL meal to the broiler diet was effective to improve feed conversion ratio without reducing body weight. SAL meal supplementation to the diet reduce fat accumulation in broiler chickens.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.439-448
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• 2011

Oxalic acid is synthesized by a wide range of plants. A few of them are forage plants that can cause oxalate poisoning in ruminants under certain conditions. In this paper, the role of some agronomic, climatic and genetic factors in minimizing oxalate accumulation in forage plants has been discussed. Research indicates that the content of oxalate in forage can be controlled by fertilizer application. For example, nitrate application resulted in higher contents of soluble and insoluble oxalates than ammonium application. With an increased rate of potassium application, soluble oxalate content showed an increasing trend and insoluble oxalate content showed a decreasing trend. With an increased rate of calcium application, soluble oxalate content showed a decreasing trend and insoluble oxalate content showed a reverse trend. Other agronomic factors such as growing season, harvesting practices, plant maturity, plant species, plant variety and plant parts can also have a large effect on oxalate accumulation. However, the potential benefits of the above approaches for improving forage quality have not been fully exploited. In addition, there is still insufficient information to fully utilize means (e.g. plant nutrients, season and soil moisture) to minimize oxalate accumulation in forage plants. Therefore, more research is required for a better understanding of the interactions between oxalate and the above-mentioned factors in forage plants.

• 한국초지조사료학회지
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• 제5권2호
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• pp.143-151
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• 1985

• 한국조경학회지
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• 제28권5호
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• pp.39-47
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• 2000

This study is to investigate the conditions closely related to the establishment of vegetation in the riparian zone: the soil condition, an important factor along with climate and light. Especially, the soil structure of the microtopographical formations in the specific area known as the riparian microtopographical zone investigated. In addition, the effect of the riparian microtopographical features on the ground water level, soil moisture content, and vegetation was studied. The results of this study are as follows; 1) At all sample sites, below the sand layer, a gravel layer is always present. This is the result of past floods. 2) Although Salix koreensis experiences frequent disturbances such as increase in river level and floods, this vegetation establishes itself in the most secure are in the microtopographical zone. 3) The growth of Phragmites japonica is closely related to the underground water level. 4) It is clear that Miscanthus sacchariflorus grows concentrated in dry areas. 5) The soil accumulation conditions differ according to the soil moisture content of each microtopgraphical feature. Accordingly, the moisture content of the soil is clearly different within the microtopographical zone. The continuous and long-term investigation and research on the relation of riparian reproduction and the relevance with location surrounding factors are necessary in the future.