• 한국작물학회지
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• 제57권3호
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• pp.280-285
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• 2012

본 연구는 국내에서 재배되고 있는 조 품종의 도정수율 증진을 위한 도정방법 및 적정 수확시기를 검토한 결과를 요약하면 다음과 같다. 제현횟수와 도정시간에 따라 제현율과 완전미도정수율의 차이가 인정되었고, 이들의 상호작용에 있어서도 유의성이 인정되었다. 조의 완전미도정수율은 제현횟수를 2회, 도정시간을 1분 30초로 하였을 때 높았다. 출수 후 수확일수에 따른 현곡천립중, 제현율, 현곡의 경도, 도정율과 완전미도정수율의 차이가 인정되었고, 이들 요인간 상호작용에 있어서도 유의적인 상관이 인정되었다. 등숙율과 완전미도정수율 향상을 위해 조생종인 황금조는 출수 후 45일(적산온도 $1,148^{\circ}C$), 중생종인 삼다메와 경관1호는 출수 후 50일(적산온도 $1,150^{\circ}C$), 만생종인 삼다찰은 출수 후 55일(적산온도 $1,168^{\circ}C$)에 수확하는 것이 가장 적당하였다.

• 한국정밀공학회지
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• 제32권4호
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• pp.387-394
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• 2015

We analyze heat generation as well as temperature distribution induced by accelerated electron impact on a target in a closed x-ray tube. For the sake of accuracy, we use Monte carlo analysis. This method gives accurate energy deposit in a medium with additional information such as secondary and backscattered electron as well as their paths. A Tungsten coated layer is divided by small rectangular cell which accumulate energy loss of primary electron beam. The cells and their accumulated energy datum are used for the input of finite element analysis. The Maximum temperature rising and temperature distribution were analyzed by transient heat analysis. Some temperature parameters such as target size and coating thickness were varied to investigate temperature sensitivity. Temperatures were compared each other to find primary variable that affect temperature rising on the x-ray target. The results will be helpful in development highresolution x-ray tube and related industries.

• Ocean and Polar Research
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• 제29권3호
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• pp.217-231
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• 2007

To explore limiting factors of spring bloom caused by waste disposal after dumping activity commenced in the Yellow Sea, we used a 1-dimensional temperature-ecological coupled model. The vertical structure of temperature and vertical diffusivity (Kh) are calculated by the temperature model with sea surface temperature using the 2.5 layers turbulence closure scheme. The ecological model applied results at the temperature model consisted of five state variables (DIN, DIP, phytoplankton, zooplankton, and detritus) forced by photosynthetically available radiation. We simulate year-to-year variations of plankton and nutrients using the coupled model from 1998 to 2000 and compare results of the model with observed data. It turned out that temperature is the growth factor of spring bloom in dumping area. During the winter the weak stratification made sufficient supply of the accumulated nutrients from the sea bed into the upper water column and led to the bloom in the coming spring. Radiation also turned out to be another important factor of spring bloom in the study area. Insufficient radiation of March 1999 showed low chlorophyll-a concentration despite sufficient nutrients in the surface.

• 한국압력기기공학회 논문집
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• 제9권1호
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• pp.48-55
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• 2013

In this paper, W-DCAP-HTR(Web-based Design Compatibility Assessment Program for High Temperature Reactor) which will be used to check the design criteria for high temperature reactor is newly proposed. To do this, the assessment procedure of the ASME Sec.III Div.5 such as time-dependent primary stress limit, accumulated inelastic strain, and creep-fatigue damage evaluation were investigated. Furthermore, the trend of candidate materials for high temperature reactor was also reviewed. Then, all assessment procedures for high temperature reactor have been computerized to enhance the efficiency and to reduce the possibility of human error during calculating procedure by hand calculation. It can be directly conducted by adopting the actual thermal and structural analysis results. The validation of W-DCAP-HTR has been demonstrated by benchmark analysis.

• Journal of Biosystems Engineering
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• 제39권2호
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• pp.69-75
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• 2014

Purpose: This paper is aimed at analyzing the heating performance of the vertical closed loop type Geothermal Heat Pump System (GHPS) distributing the farm site and providing basic data of the GHPS. Method: Seedling greenhouse heating was made from October 2012 to May 2013. The seedling greenhouse was divided into 4 sectors (A, B, C and D zone, total $3,300m^2$) with different temperatures. It was heated from 5PM to 8AM, and during the night the greenhouse was covered by non-woven fabric thermal curtains along the upper 2m of the greenhouse for temperature maintenance. In order to analyze the heating performance of the GHPS, power consumption and operating time of the GHPS, inlet and outlet water temperature of the condenser, temperatures of each zone of the greenhouse, and ambient temperature were measured. Results: When operating only one heat pump unit, heat generated in the condenser decreased as the experiment progressed and power consumption increased correspondingly. However, the heating coefficient of performance decreased from 3.3 to 2.0 rapidly. Also, when operating two heat pump units, heat generated in the condenser decreased and power consumption increased. Heating coefficient of performance decreased from 4.5 to 3.7 rapidly. When the set temperature of the greenhouse was $13.7{\sim}20.1^{\circ}C$ and minimum ambient temperature was $-20.8{\sim}4.8^{\circ}C$, the annually accumulated heat and power consumption were 520,623 kW, 142,304 kW, respectively. Conclusion: When the set temperature of the greenhouse was $13.7{\sim}20.1^{\circ}C$ and the minimum ambient temperature was $20.8{\sim}4.8^{\circ}C$, the annually accumulated heat and power consumption were 520,623 kW, 142,304 kW, respectively. When operating only one heat pump unit, the heating COP was 2.0~3.3, and when operating 2 heat pump units, it was 3.7~4.5. If several heat pumps are installed in one GHPS, it is suggested that all heat pumps be operated except in special cases. Because the scale of the water pumps are set to the scale of when all heat pump units are operating, if even one unit is not operating, the power consumption will increase. That becomes the cause of COP decrease.

• 한국작물학회지
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• 제66권4호
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• pp.289-296
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• 2021

쌀가루 가공용벼 품종인 한가루, 설갱, 신길 및 바로미2의 수발아 발생 위험을 감소하기 위한 지역별 적합 이앙기 및 이에 따른 등숙기 생육온도, 수발아 발생 위험성을 변화를 분석한 결과는 다음과 같다. 1. 쌀가루 품종의 출수기변화요인을 분석한 결과, 이앙부터 출수까지 일 평균온도 및 이앙시기변화는 포장생육일수와 부의 상관관계를 보이며 이앙시기변화에 따른 포장생육일수 변화는 유의한 상관관계를 보였다. 2. 이를 바탕으로 수발아 발생위험성 감소를 위해 등숙기 온도를 최저로 낮추기 위해 각 지역별로 안전출수한계기에 출수할 수 있는 이앙시기를 분석한 결과 대략 5월 초순(강원지역)~6월 중순(남부 내륙지역) 혹은 6월 하순(남부 해안지역)이 이앙적기로 판단되었다. 3. 각 품종별로 이앙적기에 이앙 시 수발아 발생 위험이 있는 등숙적산온도 700℃ 및 900℃의 평균온도를 분석한 결과 700℃의 경우 대체로 약 20℃, 900℃의 경우 18℃의 온도를 나타내었다. 4. 쌀가루 가공용 품종의 수발아 발생가능성을 분석한 결과, 바로미2을 제외하고는 등숙적산온도 700℃ 및 900℃에 등숙기 온도가 20℃ 미만 시 수발아 발생율은 높지 않은 것으로 판단되었다. 5. 바로미2의 경우 다른 품종에 비해 등숙기간중 수발아 발생위험성이 높아 낮은온도에서 수발아 발생위험성을 재검정하여 이앙시기를 재설정할 필요성이 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.897-900
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• 2001

Space charge distributions in silane crosslinked polyethylene (SXLPE)/ crosslinked polyethylene (XLPE) laminates was investigated using a pulsed electroacoustic (PEA) method. XLPE shows heterocharge while SXLPE shows homocharge. Positive charge is accumulated at the interface of SXLPE/XLPE laminate when applied electric field is more than 20 kV/mm. The charge profile at various temperatures was also acquired using temperature-controllable PEA system. Although applied electric field is only 8.6 kV/mm, positive interfacial charge starts to appear near 50$^{\circ}C$.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.49-54
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• 1997

In this paper, vibration characteristics are considered about thermo-visco-plastic material under periodic thermal loading. When in high temperature region, thermo-visco-plastic structure has a periodic thermal loading, it is very important in an accumulated structure like a spacestation to investigate vibration characteristic, stress-strain characteristic is considered in various 2-D model by finite element method.

• 생태와환경
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• 제45권1호
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• pp.123-128
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• 2012

연못하루살이의 성장에 필요한 유효적산온도를 구하고자 2011년 8월 7일부터 10월 10일까지 야외에 설치한 실험 수조에서 실험을 수행하였다. 실험 수조 설치일로부터 4일 경과 후 수면에서 죽은 암컷 성충 한 개체가 발견되어 산란이 이루어졌을 것으로 추정하였으며, 산란추정일로부터 39일째부터 성충이 우화하기 시작하여 61일째에 마지막 개체가 우화하였다. 우화한 성충은 총 229개체였고, 성비(암컷 수/전체 수)는 0.45로 수컷이 많았으나 통계적으로 유의하지 않았으며($p$ >0.05), 전체적으로 수컷이 먼저 우화하는 경향을 보였다. 최저 발육임계온도를 $0^{\circ}C$로 하여 유효적산온도를 산출한 값은 $1,221.8{\pm}116.0$ DD였으며, 대조습지의 연간 유효적산온도가 5,650.0 DD임을 고려할 때, 연못하루살이는 본 연구결과를 적용할 경우 야외 서식처에서 최대 1년 4세대의 생활사를 가질 가능성이 있다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.188-192
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• 2006

This study is conducted to improve efficiency of thermal storage tank. The thermal storage tank was designed to store heat energy that obtained from solar or the others heat sources. However, it has difficulties in storing heat with uniform temperature through the entire tank with respect to vertical direction. This kind of maldistribution of the supplied heat to the storage tank effects on the system performance. In this study is focused on utilization of the thermal stratification to improve thermal comfort for people in the house. To enhance temperature stratification of the tank, a distributor was designed and Installed in the middle of the tank. The distributor is supplies hottest water to the top side of the tank which is very close to inlet of the supply line to the heating load. The hottest water that is accumulated on top side of the tank is firstly supplied to the load with higher temperature. Reminder water takes a little time to warming up until desired supply temperature reached. This kind alternating selection of the supply temperature is improve thermal comfort with moderated system performance.