• 제목/요약/키워드: System condensation

검색결과 532건 처리시간 0.039초

Improvement of Direct Contact Condensation Model of RELAP5/MOD3.1 for Passive High-Pressure Injection System

  • Lee, Sang-Il;No, Hee-Cheon
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(2)
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    • pp.368-373
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    • 1996
  • A simple set of the transition criterion of the condensation regimes and the heat transfer coefficients on the direct contact condensation of the core makeup tank is developed, and implemented in RELAP5/MOD3.1 The condensation regimes are divided into two regimes: supply limit and condensation limit. In mode]ing the transition criterion between two regimes, a large-eddy model developed by Theofanous is used, and the empirical coefficient of the present large-eddy model is close to that of the large-eddy model. It turns out that the modified code better predicts the experimental data, especially the injection flow rate and the water level trend than the original code does.

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커튼월의 단열 향상 및 결로 방지를 위한 통기구조 적용방안 연구 (Application of Ventilated Cavity for Enhancing Insulation and Preventing Condensation of Curtain-wall System)

  • 이선우
    • 설비공학논문집
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    • 제29권1호
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    • pp.21-28
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    • 2017
  • Curtain-wall systems have been widely applied to buildings because of their lightweight and constructability characteristics. However, as curtain-wall systems include many building materials, vapor barriers can become damaged and condensation can occur. Due to the material properties of stone curtain-walls, the external appearance and structure of a building could be damaged and the insulating performance of the curtain-wall could be worse. Natural ventilation using an air cavity in a curtain-wall is expected to be effective for the prevention of condensation in inner walls and for the reduction of building cooling energy use in the summer. The purpose of this experimental study is to analyze the influence of a ventilated cavity on the insulating performance of a curtain-wall and the ventilated cavity depth and ratio of top opening needed to prevent condensation in a curtain-wall.

Mock-up 실험을 통한 통기성 커튼월의 단열 및 결로방지 성능평가 (An Experimental Study on Insulation and Preventing Condensation Performance of Ventilated Curtain Wall)

  • 이미진;이선우;여명석;김광우
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2006년도 하계학술발표대회 논문집
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    • pp.1081-1086
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    • 2006
  • Curtainwall systems has been applied to buildings widely for constructability. However, as cutainwall system include many building materials, they become to damaged vapor barrier and incur condensation. Natural ventilation of an air cavity in a curtainwall is expected to be an prevention of condensation in inner wall and reduce cooling energy in summer. The objective of this experimental study is to evaluating the insulation and condensation Performance of ventilated curtainwall with ventilated cavity depth and ratio of opening area.

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Design of Embedded System for Controlling Condensation System of the car

  • Lee, Dmitriy;Nam, Hyo-Duk;Seo, Hee-Don
    • 한국반도체및디스플레이장비학회:학술대회논문집
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    • 한국반도체및디스플레이장비학회 2007년도 춘계학술대회
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    • pp.281-286
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    • 2007
  • Road traffic accidents kill more than one million people a year. ESCC represents a new device, that hasn't any analogue. This embedded system, heats the car glasses, when it's needed, that makes more safety driving. It's build on Atmega128L CPU, using high-performance EEPROM CPLD ATF1504AS. Source code was written in C language. Algorithm of work was written by dew-point table. This system is not only clearing the glass from condensation, but averts condensation. ESCC began working, when input information became close to dew-point table information. Thankful this device, field of view is more widely, that increase safety level.

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근관 충전된 치아에서의 혐기성세균을 이용한 치관부 미세누출측정에 관한 연구 (AN in vitro STUDY OF THE CORONAL LEAKAGE OF TWO ROOT CANAL FILLING TECHNIQUE USING ANAEROBIC BACTERIAL LEAKAGE MODEL)

  • 김진우
    • Restorative Dentistry and Endodontics
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    • 제24권3호
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    • pp.490-494
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    • 1999
  • The aim of this in vitro study was to investigate the coronal leakage of obligate anaerobes into root canals obturated with two different techniques. 48 extracted human teeth with straight, single root canals were prepared with crown-down technique with Profile under copious irrigation until the master apical file was size 40. The teeth were divided randomly into experimental groups (40 teeth) and control groups (8 teeth). In the experimental groups, 20 teeth were obturated with lateral condensation and other 20 teeth were obturated with continuous wave technique with System B. Coronal leakage of two root canal filing technique was evaluated using anaerobic bacterial leakage model with Fusobacterium nucleatum(ATCC 25586) for 60 days. The results were as follows 1. The incidence of bacterial leakage of experimental groups was 65% in group 1 (lateral condensation) and 60% in group 2 (continuous wave technique with System B). This difference was not statistically significant (P>0.05). 2. There was no statistically significant difference(P>0.05) in leakage score between group 1 (lateral condensation) and group2 (continuous wave technique with System B).

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영상 검색의 속도 향상을 위한 차원 축소율 최적화 (Optimization of Condensation Ratio for Fast Image Retrieval)

  • 이세한;이주호;조정원;최병욱
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅲ
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    • pp.1515-1518
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    • 2003
  • This paper suggests the condensed two-stage retrieval method for fast image retrieval in the content-based image retrieval system, and proves the validity of the performance. The condensed two-stage retrieval method reduces the overall response time remarkably while it maintains relevance with the conventional exhaustive search method. It is explained by properties of the Cauchy-Schwartz inequality. In experimental result, it turns out that there is an optimal value of condensation ratio which minimizes the overall response time. We analyze the optimal condensation ratio by modeling a similarity computation time mathematically.

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반도체 식각 공정용 초저온 냉각 시스템 설계를 위한 비가연성 혼합냉매 응축 및 비등 열전달 계수 측정 (Measurement of Condensation and Boiling Heat Transfer Coefficients of Non-flammable Mixed Refrigerant for Design of Cryogenic Cooling System for Semiconductor Etching Process)

  • 이천규;이정길
    • 반도체디스플레이기술학회지
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    • 제22권3호
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    • pp.119-124
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    • 2023
  • In this study, experimental approach of the measurement of condensation and evaporation heat transfer coefficients is discussed for mixed refrigerants using in the ultra low-temperature cooling system for semiconductor etching process. An experimental apparatus was described performing the condensation and evaporation heat transfer measurements for mixed refrigerants. The mixed refrigerant used in this study was composed of the optimal mixture determined in previous research, with a composition of Ar:R14:R23:R218 = 0.15:0.4:0.15:0.3. The experiments were conducted over a temperature range from -82℃ to 15℃ and at pressures ranging from 18.5 bar to 5 bar. The convection heat transfer coefficients of the mixed refrigerant were measured at flow rates corresponding to actual operating conditions. The condensation heat transfer coefficient ranged from approximately 0.7 to 0.9 kW/m2K, while the evaporation heat transfer coefficient ranged from 1.0 to 1.7 kW/m2K. The detailed discussion of the experimental methods, procedures, and results were described in this paper.

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2방식 응축을 이용한 수산물 건조 장치 개발 (Development of drying apparatus using 2-way condensation for marine products)

  • 황재호
    • 수산해양기술연구
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    • 제42권4호
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    • pp.259-266
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    • 2006
  • In this study, the 2-way condensation system was designed applying air-to-air heat pump to dry a marine product such as squid in the winter. And to be made the drying apparatuses by this system, there are two kinds of type, A type, was set a compressor outside of the drying apparatus, B type, was set a compressor in the drying room. And then the variations of temperature in drying room were measured to compare the heating performance of the drying apparatuses between A type and B type at $-6.5^{\circ}C$, outdoor temperature. The temperature of the drying room for B type was increased to $36^{\circ}C$ but the temperature of the drying room for A type was not increased to $36^{\circ}C$, to be increased to $20^{\circ}C$.

Evaluation of Ozone Condensation System by T.D Method

  • Lee, Hee-Kab;Park, Yong-Pil
    • Transactions on Electrical and Electronic Materials
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    • 제1권2호
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    • pp.18-22
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    • 2000
  • An ozone condensation system is evaluated from the viewpoint of an ozone supplier fro oxide thin film growth. Ozone is condensed by the adsorption method and its concentration is analyzed using the thermal decomposition method, The concentration of ozone exceeds 90mol% and ozone is supplied for a sufficiently long time to grow oxide thin films. Investigation of the ozone decomposition rate demonstrates that ozone can be transferred into the film growth chamber without marked decomposition. The ozone concentration is also evaluated using a quardrupole mass analyzer and the accuracy of this method is compared with the results of the thermal decomposition method.

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스틸 커튼월의 단열성능 및 결로방지성능 평가 (Evaluation of the Thermal Performance and Condensation Resistance of a Steel Frame Curtain Wall System)

  • 김선숙;조봉호
    • 한국태양에너지학회 논문집
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    • 제33권3호
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    • pp.51-57
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    • 2013
  • Metal curtain wall systems are widely used in high-rise commercial and residential buildings. While aluminum is the most frequent used frame material, steel framing is also reemerging as a high-performance material in glazed curtain walls due to less thermal conductivity and design flexibility. The purpose of this study is to evaluate thermal performance of a steel frame curtain wall system by comparing with a aluminum frame curtain wall system. The thermal transmittance was measured according to KS 2278, and condensation resistance was calculated by the test results according to KS F 2295. The steel framing test specimen showed lower thermal transmittance and temperature descending factor compared to the aluminum framing test specimen.