• 설비공학논문집
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• 제21권1호
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• pp.41-48
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• 2009

The present study has been performed to investigate the thermal characteristics of under-ventilated compartment fire which is a typical fire condition in structures. A series of fire experiments was conducted to characterize the thermally driven flow in a 2/5 scale ISO 9705 fire compartment. Three different fuels were used in this test series, methane gas, heptane pool, and polystyrene pellets fire. In order to measure accurate temperature, double shield aspirated thermocouples reducing the effect of radiative energy exchange on temperature measurement were used in addition to bare bead thermocouples. The upper layer temperature for well ventilated fire was increased with increasing heat release rate, but it was slightly decreased for under-ventilated fire. The measured temperatures in the upper layer at the front sampling location were higher than at the rear. Thermal characteristics through the doorway were also analysed for a wide range of heat release rates. This study provides a comprehensive and quantitative assessment of fire behavior for under-ventilation condition of fire.

• Journal of Biosystems Engineering
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• 제35권6호
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• pp.393-400
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• 2010

Uniform and rapid pre-drying of mandarin is important to improve the storage quality. The aim of this study was to suggest the basic design of forced ventilated pre-drying facility for mandarin by thermal flow analysis using computational fluid dynamics software (FLUENT 6.2). Developed CFD simulation model was verified by comparison with experimental data. Airflows and temperature distributions in the five conceptional designs including existing ordinary temperature storage rooms were analyzed and appropriate basic design was determined. Analysis of the effect of arrangement of windows and exhaust fans on thermal flow in facility was carried out for more detailed design. The results of this investigation showed that the predicted airflow velocity by CFD simulation showed a good agreement with the measured value and optimum design condition for simulated forced ventilated pre-drying facility of mandarin has two exhaust fans and two windows on both sidewalls and cover on loaded mandarin.

• 한국환경농학회지
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• 제42권3호
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• pp.231-238
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• 2023

We analyzed the variations in the CO₂ concentration and temperature between a CO₂-enriched and control greenhouse. We cultivated Alstroemeria 'Hanhera' in the two greenhouses and assessed the growth parameters (stem length, stem thickness, and the number of flowers) and yield. The CO₂-enriched greenhouse had a CO₂ generator that produced CO₂ at rate of 0.36 kg/h and its windows were programmed to open when the temperature exceeded 20℃ and close when it dropped below 15℃. The control greenhouse had no additional CO₂ supplementation, and its windows were programmed to open when the temperature exceeded 20℃ and close at approximately 17:00. In the morning, CO₂ concentration remained above 500 ppm in the CO₂-enriched greenhouse, which was higher than that in the control greenhouse (approximately 370 ppm). The ventilation effect only through the side windows to reduce the temperature in both greenhouses did not appear dynamically. CO₂ supplementation promoted plant growth, resulting in a significant increase in plant yield of over 60% compared to that of the control greenhouse. Our findings suggest that elevated CO₂ concentration in the morning can significantly promote the growth and development of Alstroemeria during the winter.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.776-783
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• 2022

Since Mechanical, Electrical, and Plumbing(MEP) routing is a repetitive and experience-centered process that requires considerable time and human resources, if automated, design errors can be prevented and the previously required time and human resources can be reduced. Although research on automatic routing has been conducted in many industries, the MEP routing in AEC projects has yet to be identified due to the complexity of system configuration, distributed expertise, and various constraints. Therefore, the purpose of this study is to identify the target subjects for MEP routing automation and the constraints of each subject. The MEP design checklist provided by a CM company and existing literature review were conducted, and target subjects and constraints were identified through process observation and in-depth expert interviews for five days by visiting a MEP design company. The target subjects were largely divided into six categories: air conditioning plumbing, air conditioning duct, restroom sanitary plumbing, heating plumbing, and diagram. The findings from interviews show that work reduction and error reduction has the greatest effect on air conditioning plumbing while the level of difficulty is the highest in air conditioning duct and restroom sanitary plumbing. Major constraints for each subject include preventing cold drafts on air conditioning pipes, deviation in ventilation volume in air conditioning ducts, routing order on restroom sanitary plumbing, and separation distance from the wall on heating plumbing. In this way, subjects and constraints identified in this study can be used for MEP automatic routing.

• Asian-Australasian Journal of Animal Sciences
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• 제18권1호
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• pp.96-101
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• 2005

There were two trials involved in the experiment. Trial 1: the trial was conducted on two Taiwan Sugar Corporation (TSC) pig farms. One was located in the north of Taiwan and the other was located in the south. Both farms had wet pad and forced ventilation (WPFV) and conventional open design (COD) boar and sow houses. There were 12 Duroc boars, age ranging from 12-24 months. Half of them (6 boars) were raised in a WPFV pig house, and the other half were kept in a COD house. Semen was collected at 5-day intervals from May $1^{st}$ to the end of October. Sixteen sows (2-8 parity) were served by artificial insemination each week from the beginning of May to the end of Oct. These sows were checked for heat from 18 days to 25 days after insemination. Trial 2: there were four MPFV boar houses involved in the test. Two houses were located in the north of Taiwan, and the other two houses were located in the south. The test was conducted from January 2000 to December 2001. The total number of serviced sows by MPFV-housed boars was 35,105 head and for COD-housed boars 103,065 head. The results showed that the total semen volume, density of sperm, total sperm per ejaculate, sperm motility and morphological abnormality were significantly better (p<0.01) for boar raised in WPFV house than for COD houses. Average sperm motility in June and July was lower than for the other months. Morphological abnormality was higher during May, June and July. Although the results did not reach a significant level, the average value showed that the total volume of boar semen was higher in the north than for the south. The total semen volume production of boar raised in WPFV was higher than for boars raised in COD house, reaching a significant level only in summer. Boars kept in WPFV house had higher total sperm number than boars kept in COD house, reaching a significant level in spring (p<0.05), summer (p<0.01), and fall (p<0.05) but not in winter (p>0.05). Boars raised in WPFV house had significantly higher sperm motility than boars in COD house during spring (p<0.001), summer (p<0.001), fall (p<0.01) and winter (p<0.05). The average farrowing rate and piglets born alive were higher for boars in WPFV house than for boars in COD house, but neither reached a significant level (p>0.05). The present experiment shows that WPFV house can improve the reproduction performance of boars.

• 한국축산시설환경학회지
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• 제12권1호
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• pp.21-28
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• 2006

국민의 소득 증대로 인해 육류 및 계란의 소비량이 점차적으로 증가하는 추세에 있다. 이로 인해 산란계사의 규모가 대형화됨에 따라 기계화되었고, 이 연구에서는 고단 직립식 케이지를 사용하는 무창계사에서 기계시설이 작동 시 발생되는 소음 및 진동이 산란계의 생산성에 미치는 영향을 구명하고자 산란계사내의 소음/진동 수준을 측정 분석하였다. 전국의 13개 산란계 농장을 대상으로 하여 평상시 및 기계시설(사료급이기, 사료분배기, 집란시스템, 환기장치, 계분벨트)의 작동시에 발생되는 소음/진동을 측정하였다. (1) 평상시 소음 최대 82dB, 진동 최대 0.2072 cm/s, (2) 사료급이기 작동 시 소음 최대 90dB, 최대 진동 2.8560cm/s, (3) 사료분배기 작동시 소음 최대 90dB, 최대 진동 2.022cm/s, (4) 집란시스템 작동 시 최대 소음 87dB, 최대 진동 0.1865cm/s, (5) 환기장치 작동 시 케이지에 미치는 최대 88dB, 계사 후면 벽면에 미치는 최대 진동 2.5364cm/s, (6) 계분벨트 작동 시 최대 소음 88dB, 최대 진동 0.2387cm/s 이었다. 따라서 산란계에게 직접적이고 가장 크게 영향을 미치는 장치는 급이 시스템이였다. 이 때의 소음은 최대 90dB로 가장 높게 발생하였으며, 진동은 최대 2.8560 cm/s 발생하였다.

• Journal of Chest Surgery
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• 제29권10호
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• pp.1118-1122
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• 1996

1990년 1월부터 1995년 12월가지 43명의 환아가 다양한 심혈관수술로 인해 유발된 횡격막 마비로횡 격막 습벽형성술을 시행 받았다. 환아의 평균연령은 11.1개월이었고, 남녀 비율은 31:12였다. 횡격막 마비의 원인이 된 수술로는 변형 Blalock-Taussig단락술 및 활로씨 4징증의 전교정술이 각각 7례로 가장 많았고, 기타 동맥 전환술 6례, 심실중격결손을 동반한 폐동맥 폐쇄증에서의 unifocalization 및 변형 Fontan수술, 심실중격결손 교정 등이 각각 3례씩이었다. 마비된 부위는 우측이 17례, 좌측이 23례, 양측성이 3례였으며, 원인은 대부분 과도한 심낭 절제 및 심낭 절개면 부위의 전기소작으로 추정되었다. 원인이 된 수술후 횡격막 습벽형성술까지의 기간은 수술 당일로부터 98일까지로 대부분 2주이내에 습 벽형성술이 이루어졌다 수술방법은 2례를 제외하고 모두 횡격막 신경분지를 피해서 횡격막을 접어주는 central pleating technique 이 적용되었다. 10명의 환아가 습벽형성술후 사망했으며(조기: 7, 만기: 3), 사망원인은 전례 에서 습벽 형성술과는 무관한 것으로 사료되 었다. 36명의 조기생존자들은 습벽 형성술후 1일에서 24일 사이에 양압호\ulcorner으로 부터 벗어날 수 있었다(평균 4.5일). 6명의 환아가 습벽 형성술후 8개 월에서 52개월 사이에 fluoroscopy를 시행하였으며, 대부분 횡격막의 위치 및 운동성이 양호하였다. 결 론적으로 불가역적인 횡격막 신경 손상이 없다면 횡격막 습벽형성술은 단기적으로는 환아의 양압호흡 의존기 간을 단축시키고 장기적으로는 횡격막 기능의 완전회복을 유도할 수 있다.

• 대한간호학회지
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• 제14권2호
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• pp.38-46
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• 1984

The purpose of this study was to test the effect of the structured preoperative teaching on post-operative recovery and to observe the effects of an structured preoperative teaching on the adult surgical patient's ventilatory function ability, the length of hospital stay, the number of analgesics within a 72 hour postoperative period, the length of early ambulation. The research question investigated in this study was: What would be the effects of a structured preoperative teaching upon the adult surgical patients postoperative recovery? This study was based on a sample of 40 patients who were scheduled for abdominal surgery. They were asssigned alternately to experimental and control group. Among 40 subjects, 20 were placed in the experimental group and 20 in the control group. Preoperative ventilation function testing of control and experimental subjects was done the evening before surgery and before the patient received the structured preoperative teaching. A structured preoperative teaching was given to the subjects in the exporimental group only by writer. Postoperative testing was done the 5th postoperative day. The data were collected over a period of two months, from Aug. 8 to Oct. 31, 1983. For the analysis of the data and test for the hypotheses, the t-test with mean difference was used. The results of this study regarding the four-hypotheses were as follows: 1. Experimental group which received structured preoperative eaching will have more increase to-cough and deep breathe as measured byhis forced vital capacity(FVC), forced expiratory volume 1 (FEV1), maximal voluntary volume 15 (MVV 15) than control group without structured preoperative teaching. The ventilation function ability was more increase in experimental group than in control group, the mean difference was statistically significant at 0.01 level. Hypotheses 1 was supported. 2. Experimental group with structured preoperative teaching will have more reduced the length of hospital stay than control group without structured preoperative teaching. The length of hospital stay of the experimental group and control group were 11.90 days and 16.05 days respectively. However, the difference was. not statistically significant at .05 level. Therefore the hypothese 2 was not supported. 3. Experimental group with structured preoperative teaching will have more reduce the number of analgesics within a 72 hour postoperative period than control group. The number of analgesics within a 72 hour' postoperative period of experimental group and control group were 1.65 times and 2.4 times. The difference was not statically significant at .05 level. Therefore, the hypotheses 3 was not supported. 4. Experimental group with structured preoperative. teaching will have more reduce the length of early ambulation than control group without structured preoperative teaching. The length of early ambulation of experimental group and control group were 2.2 days and 3.5 days respectively The difference was statistically signficant at 0.05 level. Thus the hypothess 4 was supported.

• 한국화재소방학회논문지
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• 제30권6호
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• pp.137-141
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• 2016

심폐소생술에서 인공호흡은 환자와 구조자간 또는 심폐소생술 교육생들 간의 교차 감염 가능성이 높으나, 감염방지 도구인 페이스 쉴드(face shield)의 병원성 세균 여과 성능에 대한 연구 자료는 매우 부족하다. 따라서 본 연구는 인공호흡용 페이스 쉴드의 병원성 세균 여과 성능을 비교하여 전염성 질환으로부터 심폐소생술 교육생과 병원 전 구조자의 안전을 확보하기 위해 시행되었다. 대상 쉴드는 국내 심폐소생술 교육기관에서 일반적으로 사용되고 있는 FA shield와 CM shield 2종을 임의로 선정하였다. 실험방법은 실제 교육생이 입으로 불어넣은 필터에서 채취한 세균을 대상 필터에 각각 도말한 후 백밸브마스크(Bag valve mask, BVM)로 환기하여 필터의 앞면과 뒷면의 세균 검출 유무를 확인하였다. 그 결과 FA Shield는 병원성 세균 여과 성능이 있는 것으로 확인되었으나, CM Shield는 병원성 세균 여과 성능이 없는 것으로 나타났다. 결론적으로 안전한 인공호흡을 위해서는 국내에서 판매되는 페이스 쉴드의 전반적 성능 평가와 페이스 쉴드의 여과 성능 기준이 제시되어야 할 것으로 판단된다.

• 터널과지하공간
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• 제27권1호
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• pp.50-57
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• 2017

본 연구는 네트워크형 복층터널의 환기설계를 위하여 분기부지점에서 발생할 수 있는 충격손실에 대한 실험연구이다. 충격손실양을 결정할 수 있는 충격손실계수는 현재까지 종횡비가 일정한 원형이나 사각단면에 관한 설계값 및 이론식만이 존재하고 있다. 하지만 현재 국내에서 검토중인 복층터널이 종횡비가 약 1:3정도로 층고가 낮은 소형차 전용도로이기 때문에 본 조건에 맞는 충격손실계수의 제시가 필요하다. 이를 위하여 Reynolds 상사법칙이 적용된 약 1:23 스케일의 실험모델을 제작하여 큰 종횡비에 따른 분기부 지점 충격손실계수를 측정하였다. 연구 결과 분기부가 존재할 때 직선구간에 작용하는 충격손실 계수 와 분기부에서 작용하는 충격손실 계수 이 선행연구 되었던 설계값 및 이론식보다 2~3배 높게 측정되는 것을 확인하였다. 즉, 큰 종횡비가 충격손실계수에 미치는 영향이 크다는 것을 확인함에 따라서 네트워크형 복층터널의 환기설계 시 보다 정확한 설계값을 제시할 수 있을 것으로 기대한다.