• 한국생산제조학회지
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• 제20권3호
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• pp.350-356
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• 2011

In this paper, we proposed the automatic cutting mechanism of the perforation pipes in an automobile muffler. This cutting mechanism makes continuous work possible, because it performs the batch work via the sequential operation of loading, feeding, cutting, and discharging. The proposed cutting mechanism consists of the frame unit, escape unit, turning unit, feeding unit, vision system, clamping unit, spindle/cutting unit and cooling unit. And, these mechanisms have been modularized through mechanical, dynamical and structural optimized design using the SMO (SimDesigner Motion) analysis module. Also, the virtual prototype was carried out using the 3-D CAD program. The cutting process cycle is performed in the order of loading, vision processing, feeding, clamping, cutting and discharging. And the cycle time for cutting one piece was designed to be completed in four seconds.

• 한국생산제조학회지
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• 제20권4호
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• pp.446-451
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• 2011

Recent trends for the miniaturization and weight reduction of portable electronic parts have driven uses of subminiature components. Assembly of the miniaturized components requires subminiature screws of which pitch sizes are micrometer scale. To produce such subminiature screws with high precision threads, not only a precision forming technology but also a high-precision measurement technology is required. The present study covers the development of a vision inspection system for precision screws for the automatic measurement of subminiature screws with high speed and reliability. In this study, the feeding unit that transfers the subminiature screws to the inspection unit is investigated through finite element(FE) analysis. The vibration characteristics of the feeding unit are predicted through FE analyses, from which we can determine whether the subminiature screw can be stably fed into the inspection unit or not. The effects of several design parameters on the vibration characteristics are also discussed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1087-1091
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• 2004

In this study, the ultra precision centerless grinder for ferrule grinding was designed. The centerless grinder is composed of the high damping concrete bed, grinding wheel spindle unit, regulating wheel spindle unit, feeding table and dressing unit. For a newly developed centerless grinder, hydrostatic system with high precision feeding and high stiffness was proposed. The grinding and regulating wheel spindle units were composed of hydrostatic spindle and feeding table was hydrostatic table. The prototype of hydrostatic table was manufactured and tested.

• 한국정밀공학회지
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• 제17권12호
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• pp.9-15
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• 2000

• 한국생산제조학회지
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• 제20권4호
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• pp.502-508
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• 2011

In this paper, we proposed vertical feeding mechanism for a slide parts feeder using the slide type method. This parts feeder of the slide type method have been proposed to suppress the dust generation from the feeding objects. The proposed parts feeder mechanism is composed with the casing hopper, the vertical feeding unit, the in-line feeder and linear shooter unit. And, these mechanisms did modularity through optimum design by means of mechanical and dynamical analysis using the RecurDyn(multi-body dynamics) analysis module. Also were carried out the virtual prototype using the 3-D CAD program. And it had been manufactured as the prototype of the slide parts feeder. The field test for validation of performance was performed directly at the inspection line of bolt and screw. In the field test, this slide parts feeder showed an efficiency of about 1.2 times the bowl feeder. It also showed an epoch reduction in the dust generation compared to the vibration bowl feeder. So this slide parts feeder will be applied useful in the vision inspection system for a screw and bolt.

• 대한기계학회논문집A
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• 제28권1호
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• pp.31-39
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• 2004

This paper presents design solutions for cam type transfer unit in which feeding, lifting, and clamping motions are generated by cams. In order to achieve faster transfer motion, each designed cam must satisfy the given specifications such as velocity, acceleration, jerk, pressure angle, cam thickness, and torque. To reduce absolute torque magnitude and torque variation, a conjugate cam and a torque reduction cam are used respectively. The conjugate cam eliminates the redundant pre-load by using complementary cam to avoid jumping between a cam and a follower. The torque reduction cam reduces the torque variation by applying opposite torque to a cam shaft. The experimental result shows the reductions of the absolute torque value and torque variation. The improvement of working speed and life span of cam type transfer unit can be expected.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제8권2호
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• pp.25-33
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• 2002

The effects and necessity of the breast milk are well known, but the breast-feeding rate in our country is very low. One of the reason is due to the separation policy of mother and baby after delivery. The mother is in the inpatient-room and the baby is in the new-born baby room. This isolation operation of hospital get increased according to the decreasing ratio of breast feeding in Korea. Only a few hospital operates and provides the space for a new-born baby in the mother's room. The system of baby and mother in one room is adopted and operated due to the breast feeding campaign. It is very encouraging, but the space for the baby and the mother is not enough in multi-bed rooms. We should reconsider the relationship between the new-born baby unit and the obstetric ward, and design the patient's room for the baby and the mother.

• 한국항공우주학회지
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• 제42권12호
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• pp.1051-1056
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• 2014

소형인공위성에 적용을 목적으로 전기추진시스템의 연료공급부가 개발되었다. 연료공급부는 연료로 사용되는 제논을 높은 압력과 밀도의 가스상태로 저장하게 된다. 제논은 상온에서 임계점을 갖는데 발사환경에서 과도상태로 시스템에 영향을 미칠 수 있다. 따라서 발사환경에 대한 본 시스템의 기능적 구조적 안정성은 지상시험을 통한 검증이 필요하다. 본문에서는 연료공급부의 설계점과 검증시험내용을 논하고 시험결과를 정리하였다. 검증시험을 통해 본 시스템이 발사환경에 대하여 안정성을 확보하고 있는 것을 확인하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권5호
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• pp.655-667
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• 2001

This experiment was conducted to investigate the effect of feeding a low CP diet supplemented with synthetic amino acids on performance, nutrient utilization and carcass characteristics of finishing pigs fed under a three-phase feeding regimen. Ninety-six finishing pigs (Landrace$\times$Large White$\times$Duroc), $55.75kg{\pm}0.65$ of initial body weight, were blocked by weight and sex and allotted to four dietary treatments in a randomized block design. There were six pens per treatment and four pigs per pen. Pigs were fed a 16%-14%-12% CP (for phase I-II-III, respectively), sequence of diets. Dietary treatments were 1) Control, 2) Con+L (a sequence of diets reduced in CP by l percentage unit with lysine (L) supplementation, 3) Con+LMT (a sequence of diets reduced in CP by 2 percentage unit with LYS, methionine (MET) and threonine (THE) supplementation) and 4) Con+LMTT (a sequence of diets reduced in CP by 3 percentage unit with LYS, MET, THR and tryptophan (TRP) supplementation). The finishing period (55 to 105 kg) was divided into three phases (55 to 72 kg, 72 to 90 kg and 90 to 105 kg). Pigs fed either the control or Con+L diet grew faster (p<0.05) than pigs fed the Con-LMT or Con+LMTT diet. There was no difference in ADFI among dietary treatments. Phosphorus (P) digestibility was lowest in the control group and highest in the Con+LMTT group (p<0.05). Within each phase, no significant differences in dry matter (DM) and CP digestibilities were found. Although some amino acid digestibilities were affected by dietary treatments, digestibilities of essential amino acids (EAA), non-essential amino acids (NEAA) and total amino acid were not significantly influenced by dietary treatments. For the entire experiment periods, Con+L, Con+LMT and Con+LMTT treatments resulted in 13.4, 18.8 and 21.6% lower total N excretion compared with the control. Con+LMT and Con+LMTT treatments showed significantly lower BUN concentration compared with the control and Con+L treatment (p<0.05), but there was no significant difference in BUN concentration between pigs fed the control and Con+L treatment or between pigs fed Con+LMT and Con+LMTT treatments (p>0.05). Carcass length, backfat thickness and carcass grade were not significantly affected by dietary treatments (p>0.05). In conclusion, reducing dietary CP level by 1 percentage unit and supplementing only LYS at each phase could be a very beneficial feeding strategy for finishing pigs fed under a three phase feeding regimen in terms of both environmental and economical aspects.

• 임상간호연구
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• 제18권1호
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• pp.149-158
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• 2012

Purpose: The purpose of this study was to investigate incidence and factors related to diarrhea in an intensive care unit (ICU). Methods: Retrospective correlational design was used. Data were collected from reviewing medical records of 210 patients stayed at an ICU in one university hospital, Seoul. Patients were included in the study if they 1) had no gastrointestinal disorders or fecal incontinence before coming to the ICU, 2) stayed longer than 5 days at the ICU, 3) were not on stool softners, 4) were without abdominal surgery, and 5) were 20-year-old or older. Results: The incidence of diarrhea was 27.1%. Durations of ICU stay, antibiotics administration, and enteral feeding were found to be statistically significant factors correlated with diarrhea. The enteral feeding was the significant predictors of the diarrhea in ICU. Conclusion: Since characteristics of diarrhea in ICU patients is shown to be multifactorial, nursing strategies for evaluating and managing related factors are recommended.