• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1992.12a
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• pp.21-22
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• 1992

온실의 난방에 필요한 난방기기의 용량 및 연료소비량을 합리적으로 추정하기 위해서는 난방설계용 외기조건, 즉 표준기상 데이터가 필요하다. 그러나, 현재 국내에는 건물의 냉난방 설계를 위한 표준기상 자료가 대도시 지역의 일부에 대하여만 발표되어 있다. 이것은 농업시설에 대해서는 적용이 불가능하므로 농업 시설 설계를 위한 개략적인 표준기상 데이터의 선정이 요망된다. (중략)

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.11
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• pp.1023-1029
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• 2013

The integration between a gas turbine and an air separation unit (ASU) is important in IGCC plants. The portion of ASU air extracted from the gas turbine and the degree of nitrogen supply from the ASU to the gas turbine side are important operating parameters. Their effect on the gas turbine performance and operability should be considered in a wide ambient temperature range. In this study, appropriate nitrogen dilution rate and turbine inlet temperature that satisfy the two limitations of turbine blade temperature and maximum allowable power output were predicted. The air integration was set at zero. The simulation showed that the power output increases and turbine blade temperature decreases as the nitrogen dilution increases. The maximum allowable power output can be obtained under medium and low ambient temperature ranges. Under a high ambient temperature range, the achievable power is less than the maximum power.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.14 no.4
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• pp.322-356
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• 1985

The outdoor design conditions for summer and winter are basic data required for determining the heating and cooling loads and HVAC equipment capacity. The latest study reported was based on the 1960's weather data, which is widely used by HVAC design engineers in Korea. The purpose of this paper is to update the outdoor design conditions for HVAC loads and equipments based on the weather data for the 1970's. The weather conditions of 24 sites, namely Sokcho, Chuncheon, Gangreung, Seoul, Inchon, Ulreungdo, Suweon, Seosan, Cheongju, Daejeon, Chupungryeong, Pohang, Gunsan, Daegu, Jeonju, Ulsan, Kwangju, Busan, Chungmu, Mokpo, Yeosu, Jeju, Seogwipo, and Jinju have been analyzed to calculate the outdoor design conditions. This analys is performed on the basis of TAC $1\%,\;TAC\;2.5\%,\;and\;TAC\;5\%$.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.1 no.1
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• pp.3-11
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• 1972

The outdoor design conditions for the locality are the basic problem in the design of air conditioning system. The ideal solution to the basic problem is to design a building that has a capacity at maximum output just equal to the load which develops the most severe conditions for the locality occur, but in most cases, economics interferes the attainment of the ideal. Studies of weather records show that the most severe conditions do not repeat themselves every year. The weather conditions of principal cities such as Seoul, Inchon, Suwon, Taegu, Chonju, Ulsan, Kwangju, Pusan and Mokpo in Korea have been analyzed to determine the probability of occurrence of certain temperatures according to recent 10 years $(1960\∼1969)$ weather records. The outdoor conditions for winter air conditioning design are shown on Table 2. The outdoor conditions for summer air condioning design are shown on Table 7. Heating degree days are shown on Table 10 and 11.

• Journal of Navigation and Port Research
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• v.33 no.3
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• pp.241-245
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• 2009

Because of the heat island phenomenon and sea wind, there can be thermal conditions' differences around buildings at downtown and coastal area respectively in coastal city, like Busan, Incheon, Mokpo. For the final purpose of the buildings' energy saving design and operation considering of above mentioned environments differences, energy consumption including heating and cooling loads, electric loads are necessary to be accumulated and analyzed in as the database. As a part of this concept, this study aims to survey and analyze each loads of 22 apartments which has at least 100 households respectively and is located at Yeongdo island, Busan, Korea It is cleared that despite the residents living in this district can use sea wind as a natural ventilation and/or cooling methods, they mainly depends on the electric-driven air-conditioners for cooling with window-closed because of anti-salt problems of the sea wind. This leads the maximum power consumption of the surveyed-22-apartments to be appeared in August like that of inland buildings.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.15-20
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• 2017

Currently, residential air conditioners operate as a heat pump during winter. In this case, the outdoor heat exchanger acts as an evaporator obtaining heat from cold air. On the other hand, it acts as a condenser during summer transferring heat to hot air. The outdoor temperature changes significantly from high to low. Generally, the air-side j and f factors are obtained at a standard outdoor temperature. Therefore, the applicability of the j and f factors under different outdoor conditions needs to be checked. In this study, tests were conducted for a two-row louver finned heat exchanger changing the outdoor temperature to subzero. The effects of the tube-side brine flow rate were also checked. The results showed that air-side j and f factors were essentially constant and independent of the outdoor temperature, suggesting that an extension of j and f factors obtained under standard conditions to a low outdoor temperature is acceptable. All j and f factors agreed within 9% and 3%, respectively. Tests were also conducted by changing the coolant flow rate. Both the j and f factors did not change according to the flow rate, suggesting that the tube-side heat transfer correlation is acceptable.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.1
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• pp.6-12
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• 2018

Recently, The use of the curtain wall method is increasing in construction. The curtain wall construction is widely applied to the exterior wall of the building for shortening construction period and economical efficiency. However, the replacement of deterioration of the weather resistance and structural behavior of the sealing material connecting the curtain wall method and the glass frame is necessary for introduction of the stable curtain wall method and quality improvement in accordance with KS F 4910 standard. In this study, the elastic restoring force test was performed in the external environment. In this study, the deterioration of the sealant was evaluated for structural sealants. In Korea, studies on the variable displacement behavior of structural sealants are lacked. In this study, the reproduced results in laboratory conditions are compared with the deteriorating conditions exposed to the external environment, and they are reflected in the design of sealing materials in the future. According to the results of the study, it was confirmed that the existing structure sealant meets the quality standard of KS F 4910, but in the conditions performed in this study, adhesion failure of the specimen and cracking of the surface occurred. Especially, in the weather resistance test, it is necessary to evaluate the long-term durability performance of the structural sealant used in the curtain wall method by checking the insoluble state of all the test pieces. Therefore, in order to apply a conventional structural sealant to the site, it is necessary to introduce another durability performance evaluation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.653-662
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• 2014

In this study, Mokpo national maritime university Training ship Centralizes Air Conditioning System was upgraded by installing onboard an Air-cooled Air conditioner. This resulted in the improvement of the performance and operation. This study compared refrigeration performance to former equipment and improving one. And through the actual measurement study about the cabin thermal environment, it will be used as basic data for marine air conditioning design and plan in the future. At same climate condition, when the Centralized Air Conditioning System and an improved air conditioning system operated, cabin temperature was at $24{\sim}28^{\circ}C$, humidity was 55~75 % as comfortable condition, Generator load measurement showed a saving of 48KW in the average load and 8 % in the full load factor. This also resulted in a saving of daily fuel oil consumption(FOC) at around 222 [${\ell}/day$] average. On the other hand, one cadet cabin(Cadet No.21) indicated a higher temperature due to heat transmission of engine room. It found us not to consider installing additional diffuser to reduce the heat transmission.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.544-544
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• 2015

국내에는 17,500여개의 농업용 저수지가 전국적으로 분포하고 있으며, 이들 저수지는 인공호소이다. 농업용 저수지의 총 유효저수량은 2,838백만$m^3$에 달하고 있으며, 전체 수리답의 약 76%에 해당하는 593천ha의 농경지에 물을 관개하고 있다(2013농업생산기반통계연보). 최근 농어촌지역의 도농복합형태 개발 및 관광지, 유원지화로 농업용 저수지 유역의 오염원이 지속적으로 증가하는 추세에 있으며, 이로 인해 농업용수 수질이 지속적으로 악화되고 있다. 특히, 늦봄에서 초가을까지 외기온도 상승 및 저수율 저하와 함께 부영양화 증가, 녹조 대발생 등으로 수질오염도가 급상승하고 있으며, 이로 인해 호 내 물고기 폐사, 악취발생 등으로 민원이 다수 발생하고 있다. 본 연구에서는 농업용 저수지의 물리적 특성을 분석하여 농업용 저수지 수질개선을 위한 기초자료로 활용하고자 하였다. 농업용 저수지 17,489개소를 수혜면적별로 분류해 보면 5ha이하가 7,808개소(44.7%), 5~10ha이하 4,277개소(24.5%), 10~20ha 2,772개소(15.9%), 20~30ha 797개소(4.6%), 30~40ha 385개소(2.2%), 40~50ha 238개소(1.4%), 50ha이상 1,201개소(6.9%)로 구성되어 있어 50ha이하가 전체의 93.1%에 이르고 있다. 유효저수량별 분포현황은 10천$m^3$이하가 7,996개소(45.7%), 10~50천$m^3$ 6,420개소(36.7%), 50~100천$m^3$ 1,003개소(5.7%), 100~300천$m^3$ 868개소(5.0%)로 전체 시설 중 50천$m^3$이하가 전체 저수지의 82.4%로 대부분이 소규모 저수지임을 알 수 있다. 농업용 저수지를 유효수심별로 구분해보면 1m이하가 전체의 26.6%, 3m이하가 전체의 77.1%, 5m이하가 전체의 91.1%로 국내 대부분의 저수지들은 수심이 5m 이하의 저류지 형태의 저수지임을 알 수 있다. 저수지를 유역배율(유역면적/만수면적)에 따라 구분해보면 유역배율 3이하가 전체의 1.2%이고, 5이상이 전체의 97.4%를 차지하고 있다. 일반적으로 유역배율이 3이상이면 부영양화에 취약한 호소로 분류되고 있다. 국내 농업용 저수지는 대부분이 수심이 낮고, 유효저수량이 소규모이며, 유역배율이 3이상인 호소가 대부분으로 태생적으로 수질오염 및 부영양화에 취약한 구조로 되어 있음을 알 수 있다. 농업용 저수지 수질개선을 위한 종합계획 수립시에는 유입수 및 호내 대책과 함께 호소의 물리적 조건을 개선시키는 방안에 대해서도 검토가 요구된다. 특히 저수지 신규 설치시에는 수량관리 뿐만 아니라 수질도 함께 고려된 물리적 인자에 대한 설계가 이루어져야 할 것으로 판단된다.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.1
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• pp.27-33
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• 2023

An optimized design of the transportation insulated box must be considered to control the thermal damage in order to maintain the fresh condition for temperature-sensitive medicine and frozen food safety. The inside temperature of the insulated box is a natural convection enclosure state, thermal stratification naturally occurs as time passes in case of with outside heat load. The latent heat material (LHM) placement inside the box maintains the target temperature of the product for temperature fluctuations during transport, and LHM application is a common and efficient method. In this work, inside temperature stratification in an insulated box depending on the LHM pack position is numerically simulated and experimented. The insulated box is made up of vacuum insulation panel (VIP), and LHM modules are placed over six faces inside the box, with the same weight. The temperature curves for 72 hrs as experiment results clearly show the temperature stratification in the upper, middle, and lower at the LHM melting time region. However, the temperature stratification state is uniformly changed in accordance with the condition of the upper and lower placement weight of the LHM pack. And also, the temperature uniformity by changed placement weight of LHM has an effect on maintaining time for target air temperature inside the box. These results provide information on the optimized design of the insulated box with LHM.