• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2006년도 에너지.가스.기후변화학회 연합춘계학술대회 및 특별심포지움
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• pp.288-293
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• 2006

• 발명특허
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• 제6권4호통권62호
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• pp.55-55
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• 1981

• 설비공학논문집
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• 제21권8호
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• pp.468-474
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• 2009

Ground water source heat pump system is the oldest one of the ground source heat pump systems. Despite of this, little formal design information has been available until recently. The important design parameters for open system are the identification of optimum ground water flow, heat exchanger selection and well pump. In this study, the capacity of 50 RT system of two well type ground water heat pump system was used. As a result, static water level was -7 m and the level during the heating operation was -32 m, cooling operation was -40 m. The initial static water level recovered within 48 hrs. The temperature of ground water is $15.6^{\circ}C$ for heating season and $16.2^{\circ}C$ for cooling season and does not depend on the outdoor temperature. Operation efficiency of the system shows that, COP 3.1 for heating and COP 4.2 for cooling.

• 한국지열·수열에너지학회논문집
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• 제11권4호
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• pp.28-34
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• 2015

The groundwater heat pump (GWHP) systems have great potential for heating-cooling system which use annual constant groundwater temperature for heat source. Generally, the performance of GWHP system significantly depends on the geological and hydraulic properties such as hydraulic conductivity, thermal conductivity, soil condition so on. Therefore, in order to use GWHP systems efficiently, it is necessary to analyze the effect of design factors on the system performance. However, there are a few researches on the optimum design method for the open-loop geothermal system. In this research, the design factor in the open-loop geothermal system was analyzed quantitatively for the optimal design method by using numerical simulation. As a result, it was found that the temperature change of heat source depends on the design factor.

• 설비공학논문집
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• 제29권3호
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• pp.119-126
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• 2017

Recently, ground source heat pump systems are being used in buildings for cooling and heating to reduce greenhouse gas and save energy. However, ground source heat pump systems mainly use the vertical closed-loop geothermal system design rather than the open-loop geothermal system design. This is due to a lack of knowledge and few research feasibility studies. In this research, a dynamic thermal analysis numerical simulation based on a standard house model was conducted for an open-loop geothermal system. Based on heating load analysis results, the life cycle costs of a standard house using an open two-well geothermal system were analyzed and compared with a vertical closed-loop geothermal system, and a diesel boiler. As a result, it was found that using an open two-well geothermal system shows economic return on investment after three years.

• KIEAE Journal
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• 제17권3호
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• pp.119-124
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• 2017

Purpose: Groundwater heat pump (GWHP) system has high coefficient of performance than conventional air-source heat pump system and closed-loop type geothermal system. However, there is problem in long-term operation that groundwater raise at the diffusion well and reduced at the supply well. Therefore, it is necessary to accurately predict the groundwater flow, groundwater movement and control the groundwater level in the wells. In this research, in consideration of hydrogeological characteristic, groundwater level and groundwater movement were conducted analysis in order to develop the optimal design method of the two-well system using the pairing pipe. Method: For the optimum design of the two-well system, this research focused on the design method of the pairing pipe in the simulation model. Especially, in order to control the groundwater level in wells, pairing pipe between the supply well and diffusion well was developed and the groundwater level during the system operation was analyzed by the numerical simulation. Result: As the result of simulation, the groundwater level increased to -2.65m even in the condition of low hydraulic conductivity and high pumping flow rate. Consequently, it was found that the developed system can be operated stably.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.160.2-160
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• 1999

• 한국항공우주학회지
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• 제42권3호
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• pp.254-262
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• 2014

레이더 임무 스케줄링은 제한된 자원 환경에서 레이더의 성능을 향상시키기 위해 효과적으로 임무 배치를 하는 것이다. 본 논문에서는 다기능 레이더의 복수 운용 시의 스케줄링 성능 평가를 위해 총 지연 시간의 합을 목적함수로 정의하고, 실시간성을 고려한 휴리스틱 접근법을 제시한다. 제안된 스케줄링 기법들을 일반적인 임무 시뮬레이션 환경에서 비교 분석하였으며, 특히, 다기능 레이더의 복수 운용에서의 스케줄링 성능을 분석한다.

• 농업과학연구
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• 제1권1호
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• pp.35-39
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• 1974

본시험(本試驗)은 과배란처리가토(過排卵處理家兎)에서 많은 양(量)이 채취(採取)할수 있는 복수(腹水)(peritoneal fluid)가 가토수정난자(家兎水精卵子)의 in. Vitro 배양(培養)의 배양액(培養液)으로서 이용(利用)할수 있는지를 검토(檢討)하기 위하여 실시(實施)하였다. 그 결과(結果)를 요약(要約)하면 다음과 같다. 2) 2세포(細胞), 4세포(細胞), 8세포(細胞), 16세포기(細胞期)의 가토난자(家兎卵子)를 복수(腹水)를 써서 $37^{\circ}C$에서 48시간(時間) 배양(培養)한 결과 분할(分割)된 난자(卵子)의 정도(程度)는 각각(各各) 78.1%, 83.3%, 91.7% 및 93.6%로서 이들의 성적(成績)은 가토혈청(家兎血淸)으로 배양(培養)했을 경우보다도 어느 것이나 좋았다. 2) 2세포(細胞)의 난자(卵子)를 복수(腹水)로 96시간(時間) 배양(培養)했을 때 배양난자(培養卵子)의 88%가 상실기이상(桑實期以上)으로 발달(發達)되고 24%가 배반포(胚盤胞)에 이르고 있으며 가토혈청(家兎血淸)으로 배양(培養)한 성적(成績)과 거의 같은 경향(傾向)을 보였다. 이상(以上)과 같은 점(點)에서 가토난자(家兎卵子)의 배양액(培養液)으로서 가토(家兎)의 복수(腹水)가 유효(有效)하라는 것이 입증(立證) 되었다.

• 정보관리학회지
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• 제21권3호
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• pp.289-303
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• 2004

이 연구에서는 이용자가 여러 곳에 분산되어 있는 문서들을 일일이 보지 않고 하나의 요약문에서 쉽게 질의에 맞는 답을 찾을 수 있는 가장 효율적인 방안을 제시하고자 하였다. 이를 위해, 클러스터링 기법, 단락확장 기법, 두 기법의 특성을 반영한 혼합 기법 등 세 가지 복수문서 요약 기법의 성능을 평가하는 실험을 수행하였다. 요약기법 평가 기준으로는 요약 정확률과 요약문내 정보 중복도를 적용하였다. 실험결과 이용자 질의에 따라 여러 문서를 요약하는 최적 기법으로 문장검색을 기반으로 한 순차적 단락확장 기법을 제안하였다. 순차적 단락확장은 특히, 용약의 대상이 되는 문서가 대용량인 환경에서 정확한 정보를 찾아 요약문을 생성하는 성능이 가장 우수한 것으로 나타났다.