• 제목/요약/키워드: Chill system

검색결과 81건 처리시간 0.024초

내면가공 핀튜브 흡수기의 열 및 물질전달특성 (Characteristic of Heat and Mass Transfer on Inner Ribbed Notched Fin Tube Absorber)

  • 설원실;권오경;문춘근;정용옥;윤정인
    • Journal of Advanced Marine Engineering and Technology
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    • 제24권4호
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    • pp.478-485
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    • 2000
  • An experimental study of the absorption process of water vapor into lithium bromide solution was performed. For the purpose of development of high performance absorption chiller-heater utilizing Lithium Bromide solution as working fluid, the absorber is the most effective to improve the performance of an absorber because it requires the largest heat transfer area in an absorption chiller-heater system. This paper introduces bare tube and inner ribbed notched fin tube for the absorber of absorption chiller-heaters. Inner ribbed notched fin tube has about 10∼20% higher heat and mass transfer performance than bare tube conventionally used in absorbers and the it is expected to perform high heat and mass transfer. This paper will provide important information on the selection of absorber tubes in commercial absorption chill-heaters.

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지능형정보제공시스템에서 자원서비스제어부의 구현 (Implementatioon of the Resource Service Control Part on the Intelligent Peripheral)

  • 김기령;최고봉
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제5권3호
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    • pp.336-343
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    • 1999
  • 본 논문은 지능형 정보 제공 시스템(IP : Intelligent Peripheral)의 주요 소프트웨어 블록 중 하나인 자원 서비스 제어부의 구현 방법을 설명한 것이다. 본 연구의 자원 서비스 제어부는 ITU-T INCS-1에 정의된 특수자원 기능실체(SRF : Specialized Resource Function)의 상태모델을 실현시킨 소프트웨어 블록으로서 IP 하드웨어 구성요소의 하나인 특수자원교환기(SRS : Specialized Resource Switch) 의 CROS(Concurrent Realtime perating System)상에서 CHILL(CCITT High Level Programming Language)로 구현되었으며, 지능망서비스제어시스템(SCP : Service Control Point)이 보낸 지능망 응용프로토콜(INAP : Intelligent Network Application Protocol)오퍼레이션을 분석하여 IP가 보유한 자원 구동에 필요한 모든 절차를 제어한다. 또한 동시에 수신된 INAP오퍼레이션들에 대한 순서제어기능, 통계데이타 제공기능, 사용자 상호작용 종료 기능등을 제공한다. 제안된 구현기술은 자원서비스 제어부가 실제 자원을 동작시키는 IP 하드웨어 구성요소인 특수자원유닛(SRU : Specialized Resource Unit)을 클라이언트/서버형태로 유지하여 이들 자원의 상태를 관리함으로써 IP의 확장성을 보잔하여, 교환기 실시간 데이터베이스를 이용하여 IP가 생성하는 수만여개의 메시지를 효율적으로 관리할 수있다.

소실모형주조법에 의한 금속기 복합재료의 제조;고액계면과 입자거동에 관하여 (The Production of Metal Matrix Composites by Using the EPC Process;Particle Behavior at Solid-Liquid Interface)

  • 박종익;김영섭;김정민;김동규
    • 한국주조공학회지
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    • 제17권1호
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    • pp.93-99
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    • 1997
  • A possibility of production of aluminium matrix composites by using the lost foam process was investigated. Silicon carbide particles, graphite particles, and stainless steel wires were used as reinforcement materials. The reinforcement materials were introduced to the polystyrene to form patterns via injection molding process. The results obtained from this experiment can be summarized as follows. In Al/SiCp system, the particles with the radius of $100{\mu}m$ and over were entrapped in the matrix in the case of upward freezing of which solidification direction was opposite to floating direction of the particles. And few particles were entrapped in the matrix in downward freezing. In Al/graphite system, almost no particles were entrapped in the matrix except the area chill attatched. When the thickness of polystyrene slice was 4mm in Al/stainless steel wire system, the floating tendency of fibers was observed to increase as the distance from the ingate was increased.

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THE PROVISION OF QUALITY AND SAFE FOODS IN SCHOOL LUNCH PROGRAM THROUGH CENTRALIZED FOOD PRODUCTION TECHNOLOGIES

  • Clara, M.L.;Rdn, Pi-Ms
    • 대한지역사회영양학회:학술대회논문집
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    • 대한지역사회영양학회 1998년도 International Workshop School Lunch Program Expansion in Asia
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    • pp.21-30
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    • 1998
  • Sound nutrition is the basic foundation for the health of a population. Proper nutrition education through the school system can actualize the building of sound nutrition being provided at school lunch programs along with nutrition education can have far reaching impact to the health of the whole nation. In Hong Kong, the recent change over from a half day to full day school program signaled the need for a school lunch program. However, there has been no organized effort so far in Hong Kong to provide such service. School lunches are being provided by caterers who are more concerned about profits than food safetly. Alarming rates of food poisoning occurring recently in Taiwan school has further accentuated the importance of fool safety. With the advent of centralized food production technologies, Dietirians can apply their nutrition knowledge and integrate with food production processes such that safe, healthy and nutritious mcals can be produced in large quantities in a cost-effective manner serving he needs of the school children. This paper introduces the centralized food production concept, using some of the cool chill production centers for school lunch programs in the United States as examples to discuss how new technologies and management system can be integrated to yield the best outcome in food quality and safety.

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터보펌프+가스발생기 폐회로 연계시험 (Turbopump+Gas generator Closed-loop coupled test)

  • 김승한;남창호;김철웅;문윤완;설우석
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년도 제31회 추계학술대회논문집
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    • pp.129-132
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    • 2008
  • 30톤급 액체산소/케로신 추진제 액체로켓엔진 개발을 위해 연소기를 제외한 터보펌프, 가스발생기 등의 주요 엔진 구성품을 이용한 터보펌프+가스발생기 폐회로 연계시험을 수행하였다. 터보펌프+가스발생기 폐회로 연계시험에서는 엔진시스템 작동 조건을 구현하기 위해 연소기는 유량조절 오리피스로 모사하였다. 엔진시스템 모사조건에서 터보펌프+가스발생기 폐회로 연계시험기의 예냉, 시동 및 정격조건 작동이 성공적으로 수행되어 터보펌프와 가스발생기의 작동성을 검증하였다. 연계시험기의 출력 및 혼합비 제어를 위한 제어시스템도 성공적으로 검증되었다.

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Development of the Near Infrared Camera System for Astronomical Application

  • 문봉곤
    • 천문학회보
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    • 제35권1호
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    • pp.39.2-39.2
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    • 2010
  • In this paper, I present the domestic development of near infrared camera systems for the ground telescope and the space satellite. These systems are the first infrared instruments made for astronomical observation in Korea. KASINICS (KASI Near Infrared Camera System) was developed to be installed on the 1.8m telescope of the Bohyunsan Optical Astronomy Observatory (BOAO) in Korea. KASINICS is equipped with a $512{\times}512$ InSb array enable L band observations as well as J, H, and Ks bands. The field-of-view of the array is $3.3'{\times}3.3'$ with a resolution of 0.39"/pixel. It employs an Offner relay optical system providing a cold stop to eliminate thermal background emission from the telescope structures. From the test observation, limiting magnitudes are J=17.6, H=17.5, Ks=16.1 and L(narrow)=10.0 mag at a signal-to-noise ratio of 10 in an integration time of 100 s. MIRIS (Multi-purpose InfraRed Imaging System) is the main payload of the STSAT-3 in Korea. MIRIS Space Observation Camera (SOC) covers the observation wavelength from $0.9{\mu}m$ to $2.0{\mu}m$ with a wide field of view $3.67^{\circ}{\times}3.67^{\circ}$. The PICNIC HgCdTe detector in a cold box is cooled down below 100K by a micro Stirling cooler of which cooling capacity is 220mW at 77K. MIRIS SOC adopts passive cooling technique to chill the telescope below 200K by pointing to the deep space (3K). The cooling mechanism employs a radiator, a Winston cone baffle, a thermal shield, MLI of 30 layers, and GFRP pipe support in the system. Opto-mechanical analysis was made in order to estimate and compensate possible stresses from the thermal contraction of mounting parts at cryogenic temperatures. Finite Element Analysis (FEA) of mechanical structure was also conducted to ensure safety and stability in launching environments and in orbit. MIRIS SOC will mainly perform the Galactic plane survey with narrow band filters (Pa $\alpha$ and Pa $\alpha$ continuum) and CIB (Cosmic Infrared Background) observation with wide band filters (I and H) driven by a cryogenic stepping motor.

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쿡췰(Cook/Chill)시스템을 이용한 고등어조림의 HACCP 레시피 개발 및 생산과정의 품질평가 (The Development of HACCP-Based Standardized Recipe and the Quality Assessment of Cook/Chilled Soy Sauce Glazed Mackerel)

  • 곽동경;이경은;박혜원;류경;홍완수;최은정;장혜자;김성희
    • 한국식품조리과학회지
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    • 제13권5호
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    • pp.592-601
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    • 1997
  • The purposes of this study were to develop Hazard Analysis Critical Control Point-based standardized recipe applicable to cook/chilled soy sauceglazed mackerel and to evaluate the qualities related to the product flow of this item. After conducting experimental cooking, preliminary test, and analysis of recipes, critical control points were identified, control methods were determined, and HACCP-based recipe was standardized. At each critical control point, time-temperature profile was recorded and microbiological analysis (total aerobic plate counts, psychrotrophic plate count, coliform, and fecal coliform count), chemical analysis (pH, acid value and volatile based nitrogen (VBN)) and sensory evaluation of the item were done. Time-temperature data showed that the time the menu item had passed through temperature danger zone (5∼60$^{\circ}C$) during all phases was 60 min. At rapid cooling, but after cooling at room temperature, the temperature of this menu item did not drop below the ambient temperature. The results of microbiological test were negative throughout all phases following cooking and the results of chemical analysis did not change significantly in terms of storage periods except for VBN which increased on 7th day significantly(p<0.05). After steam/convection oven reheating and microwave oven reheating, the sensory score of the only appearance decreased significantly related to the storage time of overall quality profiles. But significant differences were not detected according to two reheating methods. In conclusion, this HACCP-based recipe was considered as an effective tool for assuring microbial as well as sensory quality of this cook/chilled item.

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75톤급 터보펌프의 조립체 열응력 거동 해석 (Thermomechanical Analysis of a 75ton Thrust Turbopump Assembly)

  • 윤석환;전성민;김진한
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2009년도 제33회 추계학술대회논문집
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    • pp.409-412
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    • 2009
  • 75톤급 액체로켓엔진 터보펌프 조립체에 대한 열응력 해석을 수행하였다. 터보펌프 시스템의 거시적인 거동을 조사하기 위하여 전체 조립체를 해석 대상으로 고려하였으며 해석의 효율성을 높이기 위하여 2차원 축 대칭 모델로 해석하였다. 실제 운전 조건을 고려하여 예냉, 운전 및 운전 후 단계에 대한 열전달 조건을 상정하여 해석하였으며 각 단계에서의 온도 분포, 응력 분포 및 변형량을 예측하였다. 해석에는 터보펌프를 감싸고 있는 단열재의 영향 및 베어링에서 발생하는 발열량을 고려함으로써 최대한 정확한 예측이 가능하도록 하였다.

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갱년기 여성을 위한 발건강 관리방법에 관한 문헌연구 (A Study on Foot Reflexology Therapy for Climacteric Women)

  • 이계숙
    • 한국패션뷰티학회지
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    • 제2권2호
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    • pp.12-22
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    • 2004
  • The purpose of this study is to present various ways for women to prevent and remedy the climacteric symptoms and to increase the health and quality of life of the women. The reason of this study focuses on this matter is that the conditions of climacteric era is connecter into the health of golden age. After examining the symptoms of the period, the researcher went over the foot heal care even recognized to the public. When the study considered the foot care as a medical service for the climacteric women, the method was expected as a way to improve the symptoms related to the climacteric diseases. This effect is also supported by the results of the clinical experiment and book media materials concerned. The main symptoms of climacteric period such as insomnia, irregular menstruation, stomach chill, stress were able to be decreased by feet bathing, and massage therapy on feet could also decrease pain of arms and legs, menstruation, headache and insomnia. The foot reflexology therapy made strengthen the periphery nerve, capillary vessels, and immune system, and increased the elasticity of blood vessels and the speed of the blood corpuscle, so they could enable to the blood circulation. The study expects the foot care to be positively method for climacteric symptoms with regular breathing, muscle relaxing exercise, acupuncture, exercise and alimentotherapy. The foot care doesn't have any side effects and could ives up to the modern people who want to keep their health and live long.

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터보펌프+가스발생기 개회로 연계시험 (Turbopump+Gas generator Open-loop coupled test)

  • 김승한;남창호;김철웅;문윤완;설우석
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년도 제31회 추계학술대회논문집
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    • pp.125-128
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    • 2008
  • 30톤급 액체산소-케로신 액체로켓엔진 개발의 중간 단계로서 연소기를 제외한 터보펌프 등의 엔진 주요 구성품을 이용한 터보펌프+가스발생기 개회로 연계시험이 수행되었다. 터보펌프+가스발생기 개회로 연계시험의 시험기 구성 및 시험결과를 제시하였다. 연소기를 오리피스로 모사하는 상태에서의 터보펌프+가스발생기 개회로 연계시험기의 예냉, 시동기를 이용한 시동 및 가스발생기 점화, 터보펌프 정격 구동이 성공적으로 수행되었다. 개회로 연계시험 결과는 터보펌프+가스발생기 폐회로 연계시험 수행을 위해 활용되었다.

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