• 제목/요약/키워드: Chamber Structure

검색결과 570건 처리시간 0.025초

연탄(煉炭)가스 중독자(中毒者)의 생활환경(生活環境)에 관(關)한 역학적(疫學的) 연구(硏究) (A Survey on the Environmental Conditions of the CO Patients treated by Hyperbaric Oxygen Therapy)

  • 김인달;윤덕로;최용어;윤인재;이철구;양요환
    • Journal of Preventive Medicine and Public Health
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    • 제5권1호
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    • pp.9-15
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    • 1972
  • Carbon monoxide poisoning is one of the most serious health problems in Korea, because we have been encountered with the highest incidence of CO poisoning in the world due to the unique heating system in home called 'ondal'. We opened Hyperbaric chamber unit in the Seoul National University Hospital last Jan, 1969. We have treated 848 patients as of Sept. 30., 1972, around 44 months period. We collected the informations on the environmental conditions of the place where CO intoxication actually occured by filling up the questionaire from 505 patients. The following findings were obtained. 1. Age distribution showed that the highest incidence was found in the younger age group between age of 10 to age of 29 in both sex. 2. Sex ratio of the patients was 1:1.14. 3. The socio-economic level of the patient was relatively low. 4. Housewife & housemaid were the major victims of the intoxication in the female patients & in the case of the male patient, occupational backgrounds were diverse. 5. Many patients from the middle class experienced the intoxication by sleeping at newly built room. 6. Many intoxication has been occured in the structure of houses where communicating doors are existing between living room & kitchen. 7. All findings obtained taught us again that CO poisoning is the serious by-product of the national fuel policy which put emphasis on the use of coal & socio-economic status is a very important parameter in this hazards.

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Interface Control to get Higher Efficiency in a-Si:H Solar Cell

  • Han, Seung-Hee;Kim, En-Kyeom;Park, Won-Woong;Moon, Sun-Woo;Kim, Kyung-Hun;Kim, Sung-Min
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.193-193
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    • 2012
  • In thin film silicon solar cells, p-i-n structure is adopted instead of p/n junction structure as in wafer-based Si solar cells. PECVD is the most widely used thin film deposition process for a-Si:H or ${\mu}c$-Si:H solar cells. Single-chamber PECVD system for a-Si:H solar cell manufacturing has the advantage of lower initial investment and maintenance cost for the equipment. However, in single-chamber PECVD system, doped and intrinsic layers are deposited in one plasma chamber, which inevitably impedes sharp dopant profiles at the interfaces due to the contamination from previous deposition process. The cross-contamination between layers is a serious drawback of single-chamber PECVD system. In this study, a new plasma process to solve the cross-contamination problem in a single-chamber PECVD system was suggested. In order to remove the deposited B inside of the plasma chamber during p-layer deposition, a high RF power was applied right after p-layer deposition with SiH4 gas off, which is then followed by i-layer, n-layer, and Ag top-electrode deposition without vacuum break. In addition to the p-i interface control, various interface control techniques such as FTO-glass pre-annealing in O2 environment to further reduce sheet resistance of FTO-glass, thin layer of TiO2 deposition to prevent H2 plasma reduction of FTO layer, and hydrogen plasma treatment prior to n-layer deposition, etc. were developed. The best initial solar cell efficiency using single-chamber PECVD system of 10.5% for test cell area of 0.2 $cm^2$ could be achieved by adopting various interface control methods.

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Flow-3D 모형을 이용한 순환수취수펌프장 내 흐름현상 연구 (Study for Flow Phenomenon in the Circulation Water Pump Chamber using the Flow-3D Model)

  • 하성원;김태원;최주환;박영진
    • 한국산학기술학회논문지
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    • 제20권4호
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    • pp.580-589
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    • 2019
  • 인도네시아는 전력 공급이 매우 부족한 현실에 처해 있으며, 이에 대한 해결책으로 화력발전소 건설 계획이 증가하고 있다. 화력발전소는 발전에 수반되는 엔진과 장비의 과열을 식히기 위해 냉각수 계통을 필요로 하며, 냉각수 계통 중 순환수 취수펌프장(circulating water pump chamber)은 일반적으로 ANSI (1998) 기준에 따라 설계된다. 본 연구에서는 인도네시아 K-석탄화력발전소의 순환수취수펌프장이 현장 여건상 ANSI (1998)의 확산각 설계기준 $20^{\circ}$를 만족시킬 수 없어, 수리적으로 안정된 흐름 및 구조물이 되도록 3차원 수치모형실험을 수행하였다. 수치모형으로 Flow-3D 모형을 이용하였다. Flow-3D 모형의 적용성을 검토하기 위해 Rodi (1997)의 사각형 구조물 주변에 형성되는 흐름 연구 결과와 금회 수치해석 결과를 비교하였다. 수치해석에서 도출된 종방향 유속 분포는 잘 일치함을 보여주고 있다. 순환수취수펌프장 내 설계유속을 만족시키기 위해 유속 저감에 유리한 사각형 형태의 배플을 적용하였다. 순환수취수펌프장으로 유입되는 유속이 1.5 m/s ~ 2.5 m/s로 분포되는 경우, 배플에서 분리흐름의 각도는 약 $15^{\circ}{\sim}20^{\circ}$로 발생하였다. 이를 고려하여 분리흐름 각도 이하로 하류에 배플을 배치함으로 Inlet bay 설계유속 0.5 m/s 이하를 만족시켰다.

KSTAR 진공용기 시작품 제작관련 기술분석 (Asay of the fabrication technology of the KSTAR vacuum vessel mockup)

  • 조승연
    • 한국진공학회지
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    • 제8권4A호
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    • pp.391-396
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    • 1999
  • KSTAR vacuum vessel mockup was fabricated by Korea Heavy Industries. The fabrication technology chosen for the mockup is introduced and assessed in this paper. KSTAR vacuum vessel is a huge vacuum chamber of 52 cubic meters never built in this country. Through the experiency of the KSTAR mockup fabrication, welding methods for obtaining both ultra high vacuum and structural integrity of the large vacuum chamber are extracted. The fabrication and assembly techniques for the complicated structure composed of reinforced ribs, double walls and various ports are also developed. A nondestructive test on the welding spot was performed and the results show that no major leaks violating the criterion were found. The one of the main objectives of the mockup fabrication is to measure the dimensions of the structure before and after fabrication, which plays an important role in the fabrication and the assembly. By assaying the problems occurred during mockup fabrication, the KSTAR mockup will provide the techniques for the fabrication of the main vacuum vessel.

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드렁허리 Monopterus albus 후각기관의 해부 및 조직학적 특성 연구 (Anatomy and Histology of the Olfactory Organ of Asian Swamp Eel Monopterus albus)

  • 김현태
    • 한국어류학회지
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    • 제36권1호
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    • pp.40-47
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    • 2024
  • 본 연구에서는 드렁허리 Monopterus albus 후각기관의 형태 및 조직학적 특성을 실체, 광학 및 주사전자현미경하 관찰을 통하여 조사하였다. 후각기관의 외부 형태는 피부와 평행한 폐쇄형 전비공과 후비공을 나타냈다. 내부 구조는 파이프형 비강과 뒤쪽의 위아래의 두 개 비낭으로 구성되었다. 비강의 내벽은 위중층상피층의 감각상피와 중층편평상피층의 비감각상피, 미확인기관으로 이루어졌다. 감각상피는 후감각뉴런, 지지세포, 기저세포, 림프구로 구성되며, 비감각상피는 중층상피세포와 산성의 점액다당류를 보유하는 점액세포를 보유했다. 특히, 감각상피층 내 모세혈관과 풍부한 진피에서의 혈관화는 논, 농수로, 연못, 늪과 같은 진흙 하상의 정체된 수환경에 적응 된 후각기관 내 부가적인 호흡기능의 증거이며 이는 이전에 원구류 이상의 어류 분류군에서 확인되지 않은 새로운 결과로 확인된다.

An Isothermal Temperature Source with a Large Surface Area using the Metal-Etched Microwick-Inserted Vapor Chamber Heat Spreader

  • Go, Jeong-Sang;Kim, Kyung-Chun
    • Journal of Mechanical Science and Technology
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    • 제18권4호
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    • pp.681-688
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    • 2004
  • For use of the thermal cycle of the biochemical fluid sample, the isothermal temperature source with a large surface area was designed, fabricated and its thermal characterization was experimentally evaluated. The comprehensive overview of the technology trend on the temperature control devices was detailed. The large surface area isothermal temperature source was realized by using the vapor chamber heat spreader. The cost-effectiveness and simple manufacturing process were achieved by using the metal-etched wick structure. The temperature distribution was quantitatively investigated by using IR temperature imaging system at equivalent temperatures to the PCR thermal cycle. The standard deviation was measured to be within 0.7$^{\circ}C$ for each temperature cycle. This concludes that the presented isothermal temperature source enables no temperature gradient inside bio-sample fluid. Furthermore it can be applied to the cooling of the electronic devices due to its slimness and low thermal spreading resistance.

편심된 보울의 연소실을 갖는 디젤 엔진의 연소 특성 해석 (Combustion Characteristics in the Offset Bowl Combustion Chamber Diesel Engine)

  • 김홍석;성낙원
    • 한국자동차공학회논문집
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    • 제7권7호
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    • pp.54-65
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    • 1999
  • In this study, the flow field, spray structure, and combustion process were investigated in a direct injection diesel engine having an offset bowl in a combustion chamber. The KIVA-3V code was used in this study. In order to obtain accurate results, a droplet atomization model, wall impingement model, and ignition delay concept were added to KIVA-3V code. The results showed that the offset bowl engine had a large vortex flow. The direction of this flow counteracted to the direction of fuel injection in one side of combustion chamber. It decreased local turbulent kinetic energy and eventually nonuniform combustion was resulted in an offset bowl engine. In comparison with a center bowl engine case, the peak cylinder pressure was decreased about 6%. Finally , the effect of swirl on combustion was investigated in an offset bowl engine . As the became stronger, the nouniform characteristics in combustion were increased.

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Dual-Chamber Technology: Safe and Convenient Drug Delivery for Lyophilized Biologics

  • Moore, John
    • Journal of mucopolysaccharidosis and rare diseases
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    • 제1권1호
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    • pp.28-30
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    • 2015
  • Biologics present a challenge to both the manufacturer and end user. They must usually be formulated as parenterals. However, they are often unstable in liquid form, due to their complex structure and composition. In that case, they must be manufactured using highly specialized processes, such as lyophilization (freeze-drying). Lyophilization nearly eliminates stability issues. Reducing a compound's sensitivity to temperature prolongs its shelf life. However, reconstitution can be cumbersome, involving multiple steps that increase the potential for error. Dual-chamber technology provides an effective alternative, combining a lyophilized drug and diluent in a closed system and enabling reconstitution in a few simple steps.

이중관 구조 박막형 순간온도 프로브의 응답성에 관한 연구 (A Study on the Responsibility of Thin film instantaneous surface temperature probe of a Dual-pipe structure)

  • 최석렬;박경석
    • 한국연소학회:학술대회논문집
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    • 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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    • pp.237-242
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    • 2003
  • The measurement study of instantaneous temperature at combustion chamber wall and the temperature of combustion gas has been under lots of research and development to conclude the temperature process in internal combustion engine for combustion characteristics analysis. The measurement with fast responsibility should be used for temperature measurement inside combustion chamber wall since temperature of wall changes, due to the various gas temperature, irregularly during the combustion. Therefore, thin film instantaneous surface temperature probe, which characterizes the fastest and the most accurate responsibility among contact typed temperature measurement, was used for the experiments. This new thin film instantaneous surface temperature probe improved the problems of noise and durability. The optimal coating thickness of thin film instantaneous surface temperature probe was proven to be $10{\mu}m$ for the best responsibility and durability. It also allowed the stable temperature measurement be taken up to $1,200^{\circ}C$ and proven to be read possibly from the combustion chamber wall.

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