• 한국농공학회논문집
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• 제61권5호
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• pp.101-108
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• 2019

The domestic duck industry is the sixth-largest among the livestock industries. However, 34.3% of duck houses were the duck houses arbitrarily converted from plastic greenhouses. This type of duck house was difficult to properly manage internal air temperature and humidity environment. Humidity environment inside duck houses is an important factor that directly affects the productivity and disease occurrence of the duck. Although the humidity environments of litters (bedding materials) affect directly the inside environment of duck houses, there are only few studies related to humidity environment of litters. In this study, evaporation rates from litters were evaluated according to air temperature, relative humidity, water contents of litters, and wind speed. The experimental chamber was made to measure evaporation rates from litters. Temperature and humidity controlled chamber was utilized during the conduct of the laboratory experiments. Using the measured data, a multi linear regression analysis was carried out to derive the calculation formula of evaporation rates from litters. In order to improve the accuracy of the multi linear regression model, the partial vapor pressure directly related to evaporation was also considered. Variance inflation factors of air temperature, relative humidity, partial vapor pressure, water contents of litters, and wind speed were calculated to identify multicollinearity problem. The Multiple $R^2$ and adjusted-$R^2$ of regression model were calculated at 0.76 and 0.71, respectively. Therefore, the regression models were developed in this study can be used to estimate evaporation rates from the litter of duck houses.

• 한국가금학회지
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• 제40권3호
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• pp.253-262
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• 2013

본 연구는 오리사의 바닥 형태와 난방 방법에 따른 오리의 성장 특성 및 사육 환경의 변화 양상을 비교 분석하기 위하여 수행하였다. 3처리 4반복에 반복구별로 육용오리 25수씩 총 300수를 공시하여 6주간 시험을 실시하였다. 평사 직접 난방은 일반적인 사육 방식으로 설치하였고, 바닥 난방은 PVC 파이프를 이용해 온돌식 난방으로 설치하였다. 고상식 처리구는 플라스틱 망을 지상에서 50 cm 정도 높이에 고정하여 오리분이 바닥으로 통과하여 배출되도록 하였다. 6주령 생산성에서 체중 및 사료 섭취량은 처리구간에 유의적인 차이는 나타나지 않았으나, 사료 요구율은 고상식 직접 난방이 평사 직접 난방에 비하여 유의적으로 높게 나타났다(p<0.05). 도체율 및 부분육의 비율은 평사 바닥 난방에서 복강 지방량이 0.8%로 가장 낮은 것을 제외하고 전반적으로 처리구 간에 큰 차이는 나타나지 않았다. 3주령부터 5주령까지 오리사 내 이산화탄소와 암모니아의 농도는 평사 직접 난방이 다른 처리구에 비하여 높게 측정되었다. 평사에서 깔짚 수분 함량은 직접 난방이 바닥 난방에 비해 높게 나타났으나, 이와 반대로 공기 중 분진량은 바닥 난방에서 높게 나타났다. 직접난방 처리구에서 연료 소모량은 고상식이 평사에 비하여 6주 동안 약 21% 적게 소모되었다. 오리의 외관 상태를 관찰한 결과, 오리가 깔짚과 플라스틱 망의 영향을 받아 뒤로 눕거나 다리 벌림, 발목이나 다리가 휘는 현상, 발바닥 상처 등 특이 증상이 일부 관찰되었다. 3주령과 6주령에 조사한 혈구 분석 결과는 처리구간 유의적 차이는 나타나지 않았다. 본 실험 결과, 일반 농가에서 사용하는 평사 직접 난방에 비하여 바닥 난방이나 고상식 바닥의 오리사 시설은 생산성에서 유의적 효과는 나타나지 않았으나, 일부 환경 개선이나 오리의 상태 변화에 긍정적 영향을 미치는 것으로 판단된다. 그러나 현재까지 오리사 시설에 대한 연구가 매우 부족하다는 점을 감안할 때 향후 추가적인 연구를 통한 시설개선 노력이 필요할 것으로 사료된다.

• 한국농공학회논문집
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• 제57권5호
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• pp.51-60
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• 2015

In Korea, 69.4 % of duck farms had utilized conventional plastic greenhouses. In this facilities, there are difficulties in controlling indoor environments for raising duck. High rearing density in duct farms also made the environmental control difficult resulting in getting more stressed making their immune system weaker. Therefore, a facility is needed to having structurally enough solidity and high efficiency on the environmental control. So, new design plans of duck house have recently been conducted by National Institute of Animal Science in Korea. As a study in advance to establish standard, computational fluid dynamics (CFD) was used to estimate the aerodynamic problems according to the designs by means of overall and regional ventilation efficiencies quantitatively and qualitatively. Tracer gas decay (TGD) method was used to calculate ventilation rate according to the structural characteristics of duck houses including installation of indoor circulation fan. The results showed that natural ventilation rate was averagely 164 % higher than typically designed ventilation rate, 1 AER ($min^{-1}$). Meanwhile, mechanically ventilated duck houses made 81.2 % of summer ventilation rate requirement. Therefore, it is urgent to develop a new duck house considering more structural safety as well as higher efficiency of environmental control.

• 한국농공학회논문집
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• 제63권6호
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• pp.77-88
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• 2021

Duck industry had a rapid growth in recent years. Nevertheless, researches to improve duck house environment are still not sufficient enough. Moisture generation of duck house litter is an important factor because it may cause severe illness and low productivity. However, the measuring process is difficult because it could be disturbed with animal excrements and other factors. Therefore, it has to be calculated according to the environmental data around the duck house litter. To cut through all these procedures, we built several machine learning regression model forecasting moisture generation of litter by measured environment data (air temperature, relative humidity, wind velocity and water contents). 5 models (Multi Linear Regression, k-Nearest Neighbors, Support Vector Regression, Random Forest and Deep Neural Network). have been selected for regression. By using R-Square, RMSE and MAE as evaluation metrics, the best accurate model was estimated according to the variables for each machine learning model. In addition, to address the small amount of data acquired through lab experiments, bootstrapping method, a technique utilized in statistics, was used. As a result, the most accurate model selected was Random Forest, with parameters of n-estimator 200 by bootstrapping the original data nine times.

• 한국농공학회논문집
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• 제63권1호
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• pp.37-48
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• 2021

The automatic-spreader of bedding materials was developed to reduce labor cost, and to achieve successful biosecurity in duck houses. Algorithm of the device was designed to realize a concept of the automatic unmanned operation including entire processes such as loading and spreading of the bedding materials. From the field measurement, the relationship between the expected water content reduction and weight of bedding materials per unit area according to the operation condition of the devices was induced. In the case of the measurement of particulate matters during the process of spreading works, the results of using both conventional manual-spreader and automatic-spreader were exceeded the allowable limit of inhalable and respirable dust, respectively. But, workers using automatic-spreader could be free from harmful aero-condition because they did not stay inside the facility during the spreading works. In addition, from the Duck hepatitis virus PCR test, influence on pulmonary tissue of the duck was not found. It could be expected that the development of the automatic-spreader of bedding materials for duck house can contribute to the advancement of duck breeding facilities.

• 농업과학연구
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• 제39권1호
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• pp.53-60
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• 2012

This work was conducted to evaluate the laying performance of Korean Native Ducks (KND) Pure-Line (PL). A total of 400 female pullets were hatched from PL to keep in National Institute of Animal Science, Korea. Twenty weeks old PL female ducks were divided into 4 groups (5 replications/group, 20 head/replications). Four groups were compared in a $2{\times}2$ factorial arrangement with strain (White strains, WW; Celadon strains, CC) and house type (flat house, cage house). On first egg laying day, CC strain laid eggs earlier compared to WW strain (P<0.01), but there was no significant difference between flat and cage house. Egg weight (EW) and body weight (BW) at first egg laying day have no difference among strains and houses. BW of CC strain was higher than WW strain at the age of 30 week (P<0.01). Weekly feed intake (FI) have no difference between flat and cage house, but FI of WW strain was high compared to CC strain during 20~30 weeks. There was no significant difference on EW between CC and WW strains, but EW was low at flat house compared to cage house (P<0.05). Weekly egg productions of WW strain and flat house were lower than CC strain and cage house, respectively (P<0.01). Finally, These results can provide the information that needed to introducing new strains.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 추계학술대회
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• pp.229-230
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• 2018

본 논문은 태양광 기반의 '독립형 에너지 하우스'의 전체 전력 시스템과 태양광 외장재 모듈의 에너지를 효율적으로 최대 수급하기 위한 BIPV(Building Integrated PV)용 Optimizer의 개발에 대해 기술한다.

• 한국농공학회논문집
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• 제63권1호
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• pp.1-9
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• 2021

Number of duck and its breeding facilities have been steadily decreasing for financial and social issues in Korea. Therefore, the 'turning point' for duck industry is strongly demanded. In this study, the questionary survey was carried out to provide backgrounds for developing policy and technology for duck breeding farms. The questionary survey aimed to investigate the information of operation strategy of farm, ventilation, cooling and heating. The total number of survey respondents was 74. In case of facility type, 55.4% of respondents stated they used greenhouse type, 31.3% for winch-curtain type, and 2.7% for windowless type (mechanically ventilated facility). More than 85% of the facilities were using 'natural ventilation', it meant that these situation can restrict the not only environmental control but also the supply policy for 'smart farm' of the Government. 44.6% used the combination of the cross-ventilation method and roof-ventilation method for ventilation operation in summer season, and 31.1% followed only the cross-ventilation method. In case of winter season, 36.5% used the cross-ventilation method, and 33.3% used the combination of cross and roof-ventilation, method. For the ventilation strategy, about 86.5% depended on farmer's experience. In case of heating and cooling, 79.7% were using kerosene heater for winter season, and 43.2% were using mist-spray for summer season, respectively. More than 75% stated that cooling and heating strategies were based on farmer's experience. From the analyses of the survey results, a few proposals for developing policy and technology for duck breeding farm was suggested.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2005년도 추계학술발표대회 논문집
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• pp.151-154
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• 2005

These days we are more interested in the space of architecture that how the change is likely to affect and how to be realized human. Human beings are recognizable the space and the creation of the space is eventually effected through human beings being perceptible the space of architecture and the equivalence of the space. That is the light, one of phenomenological elements, has been the first visual experience at birth. This study will concentrate on the importance of the phenomenological light especially indoors and study how architectural elements influence human beings with the light as one of the basic design factors for human life. That is exactly purpose of this research paper and this paper can make our lives worth living significant with the actively various uses inside spaces through the phenomenological light as a natural light in our human beings.

• 한국임상수의학회지
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• 제22권1호
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• pp.26-30
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• 2005

The purpose of this study is to investigate the prevalent allergens causing canine atopic dermatitis in Daejeon area. Twenty two dogs were diagnosed with atopic dermatitis by an using intradermal skin test (IDST). Allergens used for the IDST included 33 allergen extracts from nine allergen groups: house dust mites (HDM), house dust, moulds, trees, weeds, grasses, insects/fleas, epithelia and others. The 22 purebred dogs with atopic dermatitis enrolled in this study included Shi-tzus (10/22, 45.5%), Yorkshire terriers (5/22, 22.7%), Miniature pinschers (4/22, 18.2%), Pugs (2/ 22, 9.1 %) and Cocker spaniels (1/22, 4.5%). The age of onset of atopic dermatitis ranged from 5 months to 5 years old (median: 1.79 years). The males (12/22, 54.5%) and females (10/22, 45.5%) were almost equal. The number of positive reactions to allergens recorded in each dog with atopic dermatitis was 3 (9/22, 40.9%), 2 (8/22, 36.4%), 1 (3/ 22, 13.6%) and 4 (2/22, 9.1 %), respectively. The most common positive allergen reaction was HDM (52.6%). The other positive allergen reactions recorded were from house dust (17.5%), insects/fleas (15.8%), trees (5.3%), moulds (3.5%), kapok (3.5%), silk (3.5%), epithelia (1.8%), weeds (0%) and grasses (0%), respectively. Positive reactions recorded to Dermatophagoides farinae and D. pteronyssinus were in 53.3% and 46.7%, respectively. The IDST results demonstrate that the most common causative allergens in canine atopic dermatitis in Daejeon area were HDM.