• 한국사회복지학
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• 제68권3호
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• pp.105-125
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• 2016

학교결석은 학업중단이나 비행 범죄에 대한 잠정적인 조기 예측요인으로 그 중요성이 강조되고 있다. 이에 본 연구는 생태체계적 관점을 토대로 시간의 흐름에 따라 아동의 학교결석일에 영향을 미치는 다양한 보호요인과 위험요인을 경험적으로 검증하였다. 이를 위해 한국아동 청소년패널조사에서 초4 패널의 2차년도와 3차년도의 자료를 활용하였으며, 초등학교 2,378명을 대상으로 패널회귀분석의 고정효과모형을 적용하였다. 분석결과, 아동의 컴퓨터 사용시간, 부모의 학대, 학교활동참여정도, 학업성적이 학교결석일 변화에 중요한 영향을 미치는 것으로 나타났다. 특히 컴퓨터 사용시간, 부모의 학대는 학교결석에 위험요인으로 작용하였으며, 학교활동참여와 학업성적은 학교결석에 보호요인으로 작용하였다. 이러한 연구결과들을 바탕으로 우리나라 아동 청소년 문제에 대한 예방적 접근의 필요성을 강조하고 학교결석에 대한 체계적인 모니터링 시스템 구축의 필요성을 제언하였다.

• 설비공학논문집
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• 제27권8호
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• pp.402-408
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• 2015

A series of numerical simulations have been carried out to study the performances of cyclone-type oil separators, which are designed for refrigeration-system compressors. The corresponding working fluid is R22, which is a typical refrigerant, whereby a mineral-oil droplet is supplied (Ed-highlight-My interpretation). The outlet-tube length in relation to the total chamber volume is considered a design parameter. Depending on the tube length, the separation efficiency varies from 98.7% to 99.3%, while the predicted pressure drop is between 5.1 kPa and 6.4 kPa. Considering both the pressure drop and separation efficiency, the length of the outlet-port tube of the separator is 152 mm.

• 기본간호학회지
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• 제7권3호
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• pp.391-400
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• 2000

A long-term bed rest results in an inevitable foot drop. Yet preventive device such as a foot board and high-neck tennis shoes, are not widely used. This study was conducted to compare the effects of a pillow-type foot board with that of the band-type device. The band-type device of a resonable price is designed for an effective prevention of foot drop, and the convenience for it use. Among the non-equivalent control group design, foot drop preventive effects, usefulness of the device, as well as its cost effectiveness were examined. The study was carried out for four months from December 1999, and its subject had been patients and nurses of two intensive care units at K medical center in Seoul. According to the study purpose, the data collected were analyzed by $x^2-test$ and t-test. The results are as follow : 1. The ROM of ankle joint is promoted in the experimental group with a band-type device comparing the control group with a pillow type one. Dorsiflexion is particularly increased in the experimental group as compared with the control group, while planterflexion hardly shows any change. 2. The usefulness score of the experimental group nurses using the band-type device (23.97) is higher than that of the control group nurses (18.88). 3. In an aspect of the unit production cost, band-type devices are low-priced compare with pillow-type or other foot board (wooden) or high-neck tennis shoes. In summary, the newly developed band-type device is both useful and preventive for a foot drop. It is also desirable regarding to the production cost and the cost effectiveness. This fact proves that the new anti-foot drop device could be practical both for clinical care and home care. Yet the results were obtained by some subjects, it should be used after a further examination. More effective nursing intervention could be observed throughout general studies, including proper positioning and foot and ankle exercises which are the important variables of the foot drop prevention.

• 한국전산유체공학회지
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• 제19권4호
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• pp.8-13
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• 2014

A series of numerical simulation has been carried out to study performance of a cyclone type oil separator, which is designed for the compressor of a refrigeration system. Working fluid is R22, which is a typical refrigerant, and mineral oil droplet is supplied. Pitch of the helix is considered as design parameters to make a compact separator. Depending on the helix pitch, separation efficiency varies from 97.5 to 99%, while predicted pressure drop ranges from 5 to 6.5 kPa. Considering both of the pressure drop and separation efficiency, helix pitch of the separator has been designed as 50 mm.

• 설비공학논문집
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• 제17권12호
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• pp.1177-1184
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• 2005

A numerical analysis was carried out on the heat and mass transfer, and pressure drop characteristics of the modular tube bundle heat exchanger. The finite volume method with a $k-\varepsilon$ turbulence model was used for the analysis. Due to condensation, the total heat transfer rate is observed about $4\~8\%$ higher than that on dry surfaces. Total heat transfer rate increases with increase in the velocity, temperature and relative humidity of incoming air. It also increases with decreasing the aspect ratio of heat exchanger tube. The inlet velocity of cooling water has little effect on the total heat transfer when the other conditions are fixed.

• Journal of Preventive Medicine and Public Health
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• 제7권1호
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• pp.123-130
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• 1974

A socio-medical survey was carried out on 1,108 cases of pulmonary tuberculosis who had registered and 220 cases unregistered at Jeonju health center in 1973, during from June 1 to July 31, 1974. As the results of this survey, the following conclusions were obtained. 1. Of the total 1,108 cases of pulmonary tuberculosis there were 708 new cases, while remaining 400 were old cases and rate of registration was 4.0 per thousand person. 2. The highest rate of registration of the newly diagnosed pulmonary tuberculosis could be found in bacteriological examination while 54.4 per cent in X-ray examination. 3. As for the educational status of the tuberculosis patients, primary school graduates contituted the greatest proportion or 64.6 per cent, middle school graduates 13.6 per cent, high school graduates 6.8 per cent and collge graduates only 0.7 per cent. 4. By age group of the cases, at age of 20 to 29 years occupied 23.6 per cent (262 out of 1,108 cases), 17.9 per cent at age of 40 to 49 years. 5. The greatest proportion or 38.4 per cent of the cases had no occupation. 6. The living standard of the patient's household, low class constituted 60.6 per cent of the total households. 7. By distribution of residential area, farming area was 5.0 per thousand person, 4.0 in downtwon and suburban areas. 8. The greatest proportion or 70.0 per cent of positive cases in X-ray examination was unregistered in August, 63.6 per cent in July 1973. 9. 220 out of 1,108 cases(19.9%) were unregistered pulmonary tuberculosis in X-ray and bacteriological examinations. 10. For age groups of unregistered caes, most prevalent age group was 30 to 39. 11. Regarding on the cases of unregistration, 'indifference for disease' occupied highest rate with 31.9 percent' and 'private secret' with 15.7 per cent. 12. Of the total 457 cases drop-outed, there were 78 complete heald cases while remaining 207 inactive.

• 디지털융복합연구
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• 제16권10호
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• pp.333-342
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• 2018

본 연구는 학교 밖 청소년을 대상으로 문제행동에 미치는 융복합적 요인을 성별차이를 중심으로 분석하였으며, 부산여성가족개발원에서 실시된 학교 밖 청소년 연구자료를 이용한 이차자료 분석 연구이다. 연구대상자는 총 499명의 학교 밖 청소년이며, 남자는 337명, 여자는 162명이었다. 본 연구에서 조사한 문제행동은 가출, 학업중단, 성매매, 폭력, 인터넷게임중독, 절도, 약물중독 및 흡연이었다. 수집된 자료는 로지스틱 회귀분석으로 분석하였다. 본 연구의 문제행동 중 인터넷게임중독과 절도는 남자 학교 밖 청소년이 여자 학교 밖 청소년보다 높았다. 인터넷게임중독은 남자 학교 밖 청소년이 여자학교 밖 청소년보다 1.90배 높았다(p=.008, 95% CI=1.18-3.06). 절도는 남자 학교 밖 청소년이 여자 학교 밖 청소년보다 1.92배 높았다(p=.006, 95% CI=1.21-3.03). 앞으로 학교 밖 청소년의 문제행동을 예방하고 이에 대한 사회적 대책을 마련할 때, 문제행동의 양상과 성별에 따라 차별화된 접근이 필요하다.

• 전기전자학회논문지
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• 제22권2호
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• pp.384-392
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• 2018

다중출력 LDO 레귤레이터는 다양한 공급 전압이 필요한 임베디드 시스템에서 변환 효율을 개선할 수 있는 방안이 된다. 다중 출력을 위한 시분할 구조에서 LDO의 피드백 인자가 작아지면 정착시간이 길어져서 리플 전압이 커진다. 제안하는 토폴로지에서는 기준 전압을 가변하여 일정한 피드백 인자를 구현함으로써 정착시간과 리플 특성을 개선한다. $0.35{\mu}m$ 표준 CMOS 공정으로 설계한 4 채널 프로토타입의 시뮬레이션 결과 제안하는 구조는 피드백 인자가 0.4 이하인 기존 회로보다 정착시간과 리플 특성이 2배 이상 개선되는 것을 입증하였다.

• 한국인쇄학회지
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• 제28권1호
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• pp.51-63
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• 2010

Ink-jet is part of the non impact printing that shooting the ink drop from the nozzle to paper. It is very silence and express good color. There are two types of printing that continuous and drop on demand. But drop on demand process is becoming the mainstream. these days, LCD, PDP is passed more than semiconductor industry. And we expect organic EL, FED as a next display. But product equipment, main component and technology have a gap between an advanced country and us nevertheless physical development. Expecially, previous process part is depended on imports. Ink-jet printing technology that there isn't complicated photo lithography process is attracted, so ink-jet printing resolution is more embossed. But there were not many of ink-jet resolution thesis but ink-jet head or nozzle. Because, to out of the ink from the nozzle is unseeable and hard to experiment. Therefore this thesis was experimented and simulated how can ink-jet printer improved resolution by flow-3d simulation package program.

• Clinical and Experimental Reproductive Medicine
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• 제32권4호
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• pp.293-300
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• 2005

연구목적: 단일 유전자 이상에 대한 착상전 유전진단을 성공적으로 시행하기 위해서는 효과적이고 신뢰도가 높은 PCR 방법의 확립이 중요하다. 본 연구에서는 alkaline lysis와 duplex nested PCR 방법을 단일 림프구와 할구의 유전자 분석에 적용하여 그 효용성을 확인하고자 하였다. 재료 및 방법: 단일 유전자의 이상이 확인된 Duchenne muscular dystrophy (DMD), ornithine transcarbamylase (OTC) 결핍증과 epidermolysis bullosa (EB) 가계의 대상자들에서 채취한 단일 림프구와 공여 받은 배아의 할구를 이용하여 각각 PCR, restriction fragment length polymorphism (RFLP)와 direct DNA sequencing 분석을 시행하였다. 이러한 분석에서 유전자 증폭률 (amplification rate)과 두개의 allele 중에서 하나의 allele이 증폭되지 않는 allele drop-out (ADO) 빈도에 대해 살펴보았다. 결 과: 단일 림프구와 할구를 이용한 PCR 방법의 유전자 증폭률은 DMD에서 91.1%와 81.8%, OTC 결핍증에서 96.0%와 78.1%, EB에서 91.3%와 90.0%를 각각 나타냈으며, ADO 빈도는 OTC 결핍증에서 13.3%, EB에서 16.8%로 관찰되었다. 결 론: 본 연구에서 적용한 alkaline lysis와 duplex nested PCR 방법은 단일 유전자에 대한 착상전 유전진단에 성공적으로 적용할 수 있는 방법으로 생각되며, ADO 빈도를 최소화할 수 있는 효율적인 방법의 개발에 대한 지속적인 연구가 필요하다.