• 태양에너지
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• 제19권4호
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• pp.55-62
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• 1999

This study was performed to find out the influence of experimental factors on dehumidification performance and furthermore to suggest an optimal combination of factors of a total heat exchanger in a solar air conditioning system. The experimental apparatus was set up in a climate-controlled chamber where the temperature and humidity was maintained constant. In order to find out the contribution ratio of factors on dehumidification performance, the table of orthogonal arrays $L_8(2^7)$ was used. According to the results, the most influential factor on dehumidification performance was the concentration of LiCl(Lithium Chloride) solution. The next influential factors were the temperature of LiCl solution and the air flow rate. The packed layer height, packed material, and flow rate of LiCl solution had no influence on the dehumidification performance under these experimental conditions. Through the three level experiments of $L_{27}(3^{13})$, it was found that the optimal combination was $A_2B_0G_2$(concentration of solution 30 wt%, temperature of solution $15^{\circ}C$, air flow rate $253m^3/h$).

• 한국실내디자인학회논문집
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• 제15권3호
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• pp.144-154
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• 2006

Except the time when relics of a museum are exhibited or loaned to the public, they are stored in a storage. In addition, it is common view that collections are exhibited a few of total stored collections in a museum. Therefore, the environmental condition of a storage is an important factor. Hereby, the purpose of this study is to suggest the design guidelines of a storage for conservation of relics in a museum. The results from this study are as follows briefly. First, location of storages has to be located and centralized above ground against preservation environment and additional renovation. Second, for storage size, It is reasonable to secure long-term experimental data after planning about 20% of whole section in present domestic situation. Third, in order to prevent environmental deterioration due to short storage floor space, adequate storage height has to be secured against a mezzanine deck and spare storages need to be planned. Where a mezzanine deck is designed, detailed plans have to be supported for equal micro climate in a storage. Fourth, in respect of environmental control of storages, finish materials with adjustment ability on relative humidity have to be used after the system is installed jointly direct and indirect way by air chamber, considering domestic condition for management of intermittent ventilation.

• 태양에너지
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• 제20권1호
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• pp.91-96
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• 2000

This study was performed to find out how much experimental factors influence on regeneration performance in a solar air conditioning system. The experimental apparatus was set up in a climate-controlled chamber where temperature and humidity could be kept constant. In order. to investigate factors' influence on the regeneration performance of the solar air conditioning system, the model experiment was done using the 600mm $\times$ 600mm black painted aluminum regenerator. The design and analysis of experiment were done by the design of experiments, especially the table of orthogonal arrays. In order to find out how much experimental factors influence on regeneration performance, the table of orthogonal arrays $L_8(2^7)$ was used. According to the results, it was found that the most influential factor to affect regeneration performance was the concentration of LiCl solution. The next influential factors were a solar radiation, an air velocity, and the temperature of LiCl solution in order.

• 항공우주시스템공학회지
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• 제13권3호
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• pp.87-94
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• 2019

본 논문에서는 무인항공기가 수명주기 동안 노출될 수 있는 운용 환경조건 입증을 위한 시험절차를 제안한다. 시험절차는 국방과학연구소 초대형 기후환경 챔버에서 시스템 요구조건을 입증할 수 있도록 수립되었다. 다양한 환경조건 중 비행체 단위에서 요구받는 강우, 습도 및 온도(저온 저장, 저온 운용, 고온 운용 및 일광(고온 저장)) 환경조건에 대하여 MIL-STD-810G w/Change 1을 기반으로 수립된 시험단계와 상세 프로파일에 대해 제안하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.125-126
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• 2023

Recently, heat island and dry island phenomena occur frequently due to land surface development and excessive energy consumption in urban areas. As a result, the surface temperature of the building and the entire temperature of its surroundings are increased, and as a result, the durability of the building is rapidly deteriorated. In order to suppress these causes, a method of maintaining the temperature of road heating wires was implemented as a temporary measure, but this did not predict climate change. Therefore, this study is a method to measure the compressive strength, density, and thermal conductivity of lightweight concrete using waste glass foam beads. After fabricating a simple chamber, the temperature and humidity of the inside and outside were measured with an Arduino device in consideration of external factors. Therefore, if waste glass foam beads made through proper mixing are constructed in the urban center, the quality of the urban can be improved.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.51-52
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• 2023

Recently, heat island and dry island phenomena occur frequently due to land surface development and excessive energy consumption in urban areas. As a result, the surface temperature of the building and the entire temperature of its surroundings are increased, and as a result, the durability of the building is rapidly deteriorated. In order to suppress these causes, a method of maintaining the temperature of road heating wires was implemented as a temporary measure, but this did not predict climate change. Therefore, this study is a method to measure the compressive strength, density, and thermal conductivity of light weight concrete using waste glass foam beads. After fabricating a simple chamber, the temperature and humidity of the inside and outside were measured with an Arduino device in consideration of external factors. Therefore, if waste glass foam beads made through proper mixing are constructed in the urban center, the quality of the urban can be improved.

• 한국농림기상학회지
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• 제21권3호
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• pp.187-195
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• 2019

기후변화에 따른 환경 스트레스 대응 기술과 영농의사결정 플랫폼 개발을 위해서는 환경 조건에 따른 작물의 반응을 이해하기 위한 시스템 개발이 매우 중요하다. 본 연구는 한국형 SPAR 시스템이 다양한 환경 조건에서 작물 생육 반응을 어떻게 정량화하고, 향후 작물 생육 모형 개발에 어떻게 연계될 수 있는지에 대해 방향을 제시하고자 수행되었다. 한국형 SPAR 시스템은 온도, $CO_2$ 농도 등의 기상요소와 양 수분 관리 등 재배요소를 동시에 정밀 조절할 수 있을 뿐 만 아니라 군락수준에서 광합성 및 호흡 등 작물의 생육 반응을 실시간으로 정량화하기에 최적화되어 있다. 본 시스템을 통해 수집된 군락 광합성 정보는 실제 작물의 환경조건에 따른 생육량 변동을 매우 유의하게 반영하여 향후 작물 생육 모형에 실질적으로 적용 가능한 환경-유전 요인간 특이적 반응 함수 개발에 크게 활용될 것으로 기대된다.

• 한국환경농학회지
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• 제41권4호
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• pp.230-235
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• 2022

BACKGROUND: Ammonia gas emitted from nitrogen fertilizers applied in agricultural land is an environmental pollutant that catalyzes the formation of fine particulate matter (PM2.5). A significant portion (12-18%) of nitrogen fertilizer input for crop cultivation is emitted to the atmosphere as ammonia gas, a loss form of nitrogen fertilizer in agricultural land. The widely practiced method for fertilizer use in agricultural fields involves spraying the fertilizers on the surface of farmlands and mixing those with the soils through such means as rotary work. To test the potential reduction of ammonia emission by nitrogen fertilizers from the soil surface, we have added N, P, and K at 2 g each to the glass greenhouse soil, and the ammonia emission was analyzed. METHODS AND RESULTS: The treatment consisted of non-fertilization, surface spray (conventional fertilization), and soil depth spray at 10, 15, 20, 25, and 30 cm. Ammonia was collected using a self-manufactured vertical wind tunnel chamber, and it was quantified by the indophenol-blue method. As a result of analyzing ammonia emission after fertilizer treatments by soil depth, ammonia was emitted by the surface spray treatment immediately after spraying the fertilizer in the paddy soil, with no ammonia emission occurring at a soil depth of 10 cm to 30 cm. In the upland soil, ammonia was emitted by the surface spray treatment after 2 days of treatment, and there was no ammonia emission at a soil depth of 15 cm to 30 cm. Lettuce and Chinese cabbage treated with fertilizer at depths of 20 cm and 30 cm showed increases of fresh weight and nutrient and potassium contents. CONCLUSION(S): In conclusion, rather than the current fertilization method of spraying and mixing the fertilizers on the soil surface, deep placement of the nitrogen fertilizer in the soil at 10 cm or more in paddy fields and 15 cm or more in upland fields was considered as a better fertilization method to reduce ammonia emission.

• 유기물자원화
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• 제26권2호
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• pp.11-18
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• 2018

다양한 농업 부산물을 열분해하여 바이오차를 생산하고 이를 밭 농경지에 투입함에 따라 토양 화학적 변화와 온실가스 발생량에 대해 비교하여 평가하였다. 실내 인큐베이터 실험으로 항온조건은 미생물 활성이 가장 활발한 조건인 수분보수력 70%, 온도는 $25^{\circ}C$ 조건에서 8주간 실험을 수행하였다. 그 기간 동안 주기적으로 가스시료를 채취하여 온실가스를 각각 분석하였다. 누적 이산화탄소 발생량은 바이오차를 투입하지 않은 대조구에서 $258.6g\;CO_2/m^2$ 그리고 바이오차를 투입한 처리구에서는 207.1에서 $255.2g\;CO_2/m^2$의 범위로 발생하였다. 즉 바이오차가 투입됨에 따라 이산화탄소 발생량이 증가하지 않고 비슷하거나 조금 감소하는 경향을 나타냈다. 아산화질소의 누적 발생량은 대조구에서 $2,890.6mg\;N_2O/m^2$ 그리고 바이오차를 투입한 처리구에서는 379.7에서 $525.2mg\;N_2O/m^2$ 의 범위로 발생하였다. 바이오차가 투입됨에 따라 아산화질소 발생량은 80% 이상 감축할 수 있었다. 따라서 바이오차를 밭 농경지에 적용한다면 아산화질소 발생량을 감축할 수 있는 소재로 활용할 수 가 있을 것이다.

• 한국농림기상학회지
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• 제20권2호
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• pp.175-182
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• 2018

본 연구는 기온에 따른 봄배추 '춘광'의 재배 적기를 밝혀 농가에 적정 재배시기를 제공하기 위해서 수행되었다. 기온이 외기보다 $6^{\circ}C$까지 단계적으로 상승하도록 설계된 온도구배 터널을 3개의 구역(외기+$2^{\circ}C$, A; 외기+$4^{\circ}C$, B; 외기+$6^{\circ}C$, C)으로 나눈 후 작기(2017.3.6., 1차; 3.20., 2차; 4.3., 3차)에 걸쳐 정식하였다. 재배기간 동안의 생육도일(growing degree days, GDDs)은 1차 A, 1차 B, 2차 A, 1차 C, 2차 B, 3차 A, 2차 C, 3차 B, 3차 C 순으로 높았다. 구중은 1차 B, 1차 C, 2차 A 처리구에서 높게 나타나 처리간 높은 유의적 차이를 보였으나 생태적인 특성(엽수, 엽면적, 최대엽의 엽장 및 엽폭 등)은 차이가 없었다. 다만, 생육초기 $13^{\circ}C$ 이하의 저온에 감응하였던 결과로 1차 A 처리구에서 5.5%의 추대현상이 발생하였다. 또한 2차 C, 3차 A, B, 및 C 처리구에서 기온이 높아짐에 따라 각각 11.0, 5.5, 33.3, 및 44.4%의 속썩음 현상이 발생하였다. GDDs에 따른 배추 구중은 587 GDDs까지 증가하다 729 GDDs 이후에는 오히려 감소하였다. GDDs에 따른 배추 수량과 적정 재배시기 예측식에서 최대 기대수량은 정식 후 64일 기준 GDDs가 601일 때 16.3MT/10a이었다. 최대 수량의 95%(약 15.5MT/10a) 이상을 재배 적기로 설정할 때 적정 범위는 478~724 GDDs로 산출되었다. 재배적기 예측식의 검증 결과, 봄배추 주산지인 진도, 해남, 나주, 서산, 평택의 GDDs는 각각 634, 619, 666, 652, 및 719이었고, 예측식에서 산출된 범위(478~724 GDDs)에 포함되었다. 결과적으로 봄배추의 재배 최적기는 예측식의 최대값인 수확기준 601 GDDs이며 적정 범위는 호냉성인 온도 특성을 감안하여 478~724 GDDs인 것으로 판단된다.