• 대한기계학회논문집A
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• 제34권1호
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• pp.91-96
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• 2010

유압호스는 적용되는 압력에 따라서 저압, 중압, 고압으로 구분되어진다. 승용차의 파워스티어링 시스템은 저압부와 고압부 시스템으로 구분되어질 수 있다. 본 연구의 목적은 차량이 회전할 때 발생되는 충격압력이 고압호스부에 적용될 때 수명을 예측하는 것이다. 내부와 외부 조건을 조절하기 위해서 충격 압력과 작동유의 온도는 충격압력 시스템에서 제어되는 것이 필요하다. 충격압력 시험에서 압력과 작동유 온도만을 조절하여 얻은 결과는 고압호스의 수명을 예측하기 위한 조절형 가속수명시험을 적용하였으며, 또한 유한요소법으로 스웨이징부를 해석하였다.

• 한국해양공학회지
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• 제25권6호
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• pp.80-85
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• 2011

The Ultrasonic Nanocrystal Surface Modification (UNSM) technology improves the fatigue life of a torsion bar by inducing compressive residual stress on the surface layer. The UNSM is applied to replace the presetting method and shot peening technology. The torsion bar must be changed periodically because of a lack of durability and a phenomenon related to the stress relaxation. The torsion fatigue test specimens were made of DIN17221 material, and the results showed that the fatigue life was 5 times more than under durability test conditions. A comparison test between the commercial vehicles' presetting method and shot peened torsion bar and the UNSM torsion bar showed that the UNSM could replace the presetting method and shot peening.

• Journal of Welding and Joining
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• 제33권6호
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• pp.49-54
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• 2015

Welding process is of importance to assemble products or structures, but also the process is structural weakness due to stress concentration in welding joint. The fatigue design of welded joint requires time & labor consuming fatigue test because the fatigue life is various according to the depth of joint, joint type and load type etc. In fatigue design codes, they guide to classify welding joints with their shape( BS7608, IIW Documents) and provide fatigue assessment information. In terms of numerical method for fatigue analysis, it is also difficult to decide the stress peak in joint because of mesh sensitivity which means that stress value is varies with element type or size on stress concentration zone. Hot-spot method is used generally, but Battelle of United States proposed Master S-N Curve based on structural stresses converted by mechanical equilibrium theory. In this research, we extracted master S-N curve from Battelle's fatigue test DB including test data of various welding joints to apply on Non-Load-Carrying cruciform Joint. Comparing fatigue results between the case of using normal stress and case of structural stress cor the cruciform Joint, The suggested Battelle method showed successive results.

• 동아시아식생활학회지
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• 제20권1호
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• pp.84-94
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• 2010

Physico-chemical analysis and sensory test of loin of lamb were carried out by four different methods such as grilling, pan-frying, oven-roasting and boiling. The crude fat content was all the same at three cooking methods except boiling. The moisture content was not different among grilling, pan-frying and oven-roasting. Hunter's color L-value(lightness) was lowest at grilling method. However, the heating loss appeared greatly at grilling. The hardness of the lamb-loin after cooking showed big differences with the control except boiling treatment. Amino acids in fillet contained highly in the order of glutamic acid > aspartic acid > cystein. The grilling showed a good value not only color of a sensory test but also the appearance. The oven-roasting cooking gave the tenderness and juiciness. The oven-roasting method showed good sensation to overall taste. Therefore, the oven-roasting (at $150^{\circ}C$ for 9 minutes) was suggested as the superior method when the loin of lamb is cooked for reducing off-flavour.

• 대한기계학회논문집A
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• 제26권6호
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• pp.1069-1076
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• 2002

The high temperature creep behavior of heat machine systems such as aircraft engines, boilers and turbines in power plants and nuclear reactor components have been considered as an important and needful fact. There are considerable research results available for the design of high temperature tube materials in power plants. However, few studies on the Initial Strain Method (ISM) capable of securing repair, maintenance, cost loss and life loss have been made. In this method, 3 long time prediction Of high temperature creep characteristics can be dramatically induced through a short time experiment. The purpose of present study is to investigate the high temperature creep lift of Udimet 720, SCM 440-STD61 and 1Cr-0.5Mo steel using the ISM. The creep test was performed at 40$0^{\circ}C$ to $700^{\circ}C$ under a pure loading. In the prediction of creep life for each materials, the equation of ISM was superior of Larson-Miller Parameter(LMP). Especially, the long time prediction of creep life was identified to improve the reliability.

• 한국산학기술학회논문지
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• 제20권11호
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• pp.44-55
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• 2019

본 연구는 간호사를 대상으로 초기 심정지 5분 간 수행능력, 자신감 향상을 위해 전통적 시뮬레이션 교육 방법과 Rapid Cycle Deliberate Practice(RCDP) 시뮬레이션 교육 방법을 받은 전·후 변화를 확인하고 두 그룹 간의 수행 능력, 자신감, 만족도를 비교 하고자 시도되었으며 연구 대상자는 서울 소재 병원의 간호사로 그룹 1은 62명으로 RCDP 시뮬레이션 방법을 그룹 2는 60명으로 전통적 시뮬레이션 교육 방법으로 총 122명의 간호사에게 전문 소생술 교육을 진행 하였다. 2019년 3월 18일부터 29일 까지 자료 수집을 하였으며 자료 분석은 SPSS Version 23.0 프로그램으로 서술적 통계, Fisher's exact test, t-test, Wilcoxon sign rank test, Mann-Whitney U-test를 활용하여 분석하였다. 연구 결과 RCDP와 전통적 시뮬레이션 교육의 두 그룹 간에는 수행 능력의 일부 항목(z=-2.02, p=0.044 / z=-2.42, p=0.015 / z=-3.03, p=0.002)은 유의한 차이를 보였으나 수행 자신감(z=0.388, p=0.699)과 만족도(t=.72, p=0.476)에서 두 그룹간의 차이는 없었다. 본 연구는 전통적 시뮬레이션 교육 방법과 RCDP 시뮬레이션 교육 방법 모두 간호사의 전문 소생술 수행 능력 및 자신감을 높이는데 효과적인 교육 방법임을 확인하였다. 따라서 간호사 대상 전문 소생술 교육시 교육 대상 및 내용에 따라 적절한 시뮬레이션 방법을 적용하고 다양한 분야에 RCDP 시뮬레이션 교육 방법을 활용하여 효과성을 확인 해 볼 것을 제언한다.

• 가정과삶의질연구
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• 제8권2호
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• pp.101-118
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• 1990

The purpose of this study is to examine the stress level and factors percepted by the married women during family life, and to identify the related variables influencing on stress level. For this purpose, questionnaires were distributed to the 650 married women who have been living in seoul. Among them 463 data were selected. For data analysis, the statistical method such as the factor analysis frequency distribution percentile , t-test, ANOVA, Duncan's Multiple Range Test and Stepwise Regression Analysis were used. the major findings were summarized as follows; 1) The general tendancy of the stress level percepted by the married women during family life was relatively low. 2) The household background variables(age, level of education, income, type of family, number of children, status of employment ) have turned out to be significant on the stress level of married women except family type. 3) All the social-psychological variables(socio-economic status, communication interaction, resources perception, psychological satisfaction) showed significant differences according to the stress level percepted by the married women during family life. 4) The level of work identity was the important factor on the stress level percepted by the married women during family life. 5) In Stepwise Multiple Regression Analysis, the married women's stress level during family life was greatly influenced by variables such as the resource perception and the psychological satisfaction.

• 복식
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• 제53권1호
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• pp.87-98
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• 2003

The purpose of this study was to investigate body image as attitude toward physical appearance, and appearance-management behavior, and to analyze the relationship between body image and life style which affects consumer behavior. The method of the study was survey research by using questionnaires. Subjects were 323 women in their twenties. Statistical analysis methods were frequency, percentage. factor analysis, discrimination analysis, one-way ANOVA, x 2- test, and Duncan's multiple range test. The results of the study were as follows. As for appearance-management behaviors of woman in her twenties. 60.1% of all respondents experienced in diet. 31.6% experienced in plastic operation, 47.4% experienced in skin care, 44.9% experienced in perfect make up, and 84.8% experienced in hair dyeing. The group with high appearance concern showed high body satisfaction. Life-style factors were analyzed into 5 factors. The group with low appearance concern considered active family-focus life factor importantly, the group with middle appearance concern considered social life factor, and the group with high appearance concern considered self-focus life type and conspicuous consumption life factor. A significant difference was found in body image between groups according to social level and demographic characteristics. The female group in the mid twenties who majors in arts and athletics, resides on southern part of Han river, and belongs to high society was analyzed to show high appearance concern and body satisfaction. and many experiences of appearance-management behaviors.

• 한국추진공학회지
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• 제18권3호
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• pp.17-25
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• 2014

본 논문은 장약포의 저장기간에 따른 파단하중 저하에 관하여 감마과정 모델을 이용하여 저장수명을 예측하는 방법에 대한 연구결과이다. 추진제의 자연분해로 발생하는 질소화합물과 장약포의 화학반응은 파단하중을 저하시킨다. 장약포의 가속수명시험 결과에 감마과정 모델을 적용하여 시간의 경과에 따른 상태와 수명을 확률분포로 표현하였다. 저장수명은 중위수로 표현하고 품질보증을 위한 정책결정기준으로 $B_1$ 또는 $B_5$ 수명을 활용하는 것이 적절하다.

• 임상간호연구
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• 제14권1호
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• pp.25-32
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• 2008

Purpose: The purpose of this study was to examine quality of life with patients in 12 months after coronary artery bypass graft surgery, compared with general population. Method: A cross-sectional comparative study was designed. Study participants were 90 adults who had undergone CABG surgery (n=45) in experimental group and general population (n=45) in control group. The subjects were asked the questionnaire (SF-36, Short Form-36) regarding the quality of life. The data were analyzed by the SPSS 13.0 program including frequency, percentage, $x^2$ test, t-test and One-Way ANOVA. Results: There were no significant differences in the quality of life between two groups including physical functioning (t=-.938, p=.351), role-physical limitation (t=-.322, p=.748), bodily pain (t=-.938, p=.351), general health (t=-.1418, p=.888), vitality (t=-.816, p=.417), social functioning (t=.720, p=.474), role-emotional limitation (t=-.710, p=.479), mental health (t=-.431, p=.667). Conclusion: Even though patients in experimental group had operation experience, the quality of life examined on the time of 1 year after bypass surgery is similar in that of general population. We suggest the study change the design as examination of quality of life before and after coronary artery bypass graft surgery.