• Corrosion Science and Technology
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• 제3권5호
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• pp.209-215
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• 2004

Flexible hydraulic hose assembly that consists of hose and joints is used widely on various construction heavy equipments, agricultural machines, motor vehicles, and industrial heavy machines that require flexibility on hydraulic pipelines. It is classified by the maximum usage pressure which is determined by the winding layers of coiling steel wire and the inner diameter of the hoses. In this paper, we designed and performed an accelerated life test for assessing the reliability of a flexible hydraulic hose assembly. In the proposed accelerated life test, typical impulse pressure testing method is applied with the half omega flexing operation to simulate the practical flexing motion of the hose assembly.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.562-567
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• 2003

This paper presents the method of Rate of Loading(ROL) improvement for the Motor Operated Gate Valve operating in high differential pressure condition. The character of ROL and Stem Factor is analyzed. Static test and dynamic test were performed and acquired the diagnosis signal for the valve closing stroke. The result of this study is the modification of stem factor is very important factor for the ROL improvement. In order to obtain the same value of dynamic test thread friction coefficient stem and stem nut should be combined appropriately.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.465-467
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• 2012

액체로켓엔진 연소기의 연소시험을 수행하기 위한 가압식 시험설비의 배치 계획과 시험동내 위치하는 주요 실별 용도를 제시하였다. 본 논문에서 제시된 기반시설의 배치도는 자연 지형을 최대한 활용하고, 비행 모델의 초기 자세를 모사할 수 있도록 수직형 시험설비를 계획함에 따라 결정되었다.

• 한국의류학회지
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• 제35권9호
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• pp.1039-1048
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• 2011

This research develops a basic design structure for scuba diving wetsuits suitable for the shape of Korean men in their 30's as well as enhances the reduction rate for underwater activity. The clothing pressure and fitness tests were performed using four different types of body suits. The usable data of the tests were coded for further statistical analysis that includes one way-ANOVA test and S-N-K Multiple Range Test by using SPSSWIN 17.0. An analysis of the results shows: (1) The results of the clothing pressure test (using a dummy) indicated that the larger the reduction rate, the stronger the clothing pressure gets (with an exception on the knee area). It has great impact on clothing pressure with regards to the different body parts. The different reduction rates should be applied to body parts accordingly. (2) In the case of test subjects, the overall mean values of the clothing pressure were lower than the ones with the dummy (attributable to the cushion function of body skin and muscle as well as the high stretch of the fabric). (3) In evaluating the subjective fit test of four types of body suits, a statistically significant difference was found in the relation between pattern reduction rates and all parts of the body. It was revealed that the reduction rate of 'B' pattern (X: 4%, Y: 3%) was the most suitable pattern and the 'B' pattern scored highest in the motion functional fit test performed by a test subject.

• 한국항공우주학회지
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• 제33권3호
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• pp.99-106
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• 2005

액체로켓엔진 개발에서 필수 단계인 연소안정성 확인을 위한 연소안정성 평가시험(stability rating test) 방법의 개발을 위해서는 압력교란장치의 특성과 더불어 안전한 연소시험 절차(sequence)의 확립이 필수적이다. 따라서 본 연구에서는 연소안정성 평가시험을 위해 개발된 펄스건을 액체로켓엔진의 연소시험에 실제로 적용하기 위한 단계로서, 적절한 연소 시험 절차를 개발/검증하고자 하였다. 먼저 펄스건을 실제로 연소실 외벽에 장착하게 되는 압력파 유도장치를 설계하고, 펄스건의 오작동을 방지하기 위한 압력파 유도장치 내부의 냉각시스템의 설계 및 시험을 수행하였다. 이러한 일련의 연소시험 단계를 통하여 실물형 액체로켓엔진에서의 연소안정성 평가시험이 가능한 적절한 시험 단계를 국내 독자적으로 개발하는데 성공하였다.

• 대한간호학회지
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• 제35권1호
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• pp.125-134
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• 2005

Purpose: The purpose of this study was to identify the influencing factors on the development of pressure ulcers in patients undergoing surgery which lasted more than two hours. Method: One hundred nineteen surgical adult patients were included in the study. Data was measured on each participant from December 2003 to February 2004. It was collected using a structured researcher-administered sheet and analyzed by descriptive statistics, t-test, chi-square test and logistic regression analysis. Result: The prevalence of a perioperative pressure ulcer was 26.1%. The level of moisture, friction and shear, length of surgery, and perioperative irrigation were significantly higher in the pressure ulcer group than those in the non-pressure ulcer group. The level of activity and level of consciousness were significantly lower in the pressure ulcer group than those in the non-pressure ulcer group. Significant influencing factors on the development of pressure ulcer were 'moisture' and 'irrigation' and those variables explained 23.1% of varience in the development of a pressure ulcer during surgery. Conclusion: It is necessary to develop a strategy to prevent pressure ulcer by taking 'moisture' and 'irrigation' into account during the preoperative, perioperative and postoperative period.

• 한국소음진동공학회논문집
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• 제21권1호
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• pp.18-23
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• 2011

With hydraulic noise test facility, a variety of tests were performed to investigate the pulsation pressure generation mechanism and its transmission characteristics and to derive the noise control methodology. Many experiments were carried out by changing average pressure, flow rate, pump speed, hose length and MCV spool condition. From the test results, the correlations between pulsation pressure and other design parameters, such as static pressure, flow rate and MCV spool opening area and length of hose, were found out. And also each contribution factors were evaluated from the regression analysis. By changing hose length, the pulsation pressure resonance phenomenon was investigated. In order to find out the pulsation pressure reduction measures pulsation pressure analysis, such as pulsation pressure of hydraulic pump itself and pulsation pressure of hydraulic system, by using AMESim were studied. In addition hydraulic silencer was developed based on the Helmholtz resonator. And its performance was evaluated by installing the silencer at the excavator.

• Food Quality and Culture
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• 제1권1호
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• pp.34-39
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• 2007

The effects of pressure cooker brand awareness, in terms of rice cooking performance, were evaluated using consumer acceptability tests. A blind test was performed using rice samples cooked by 3 different pressure cookers without any brand information, and a brand awareness test followed with the same informed consumer panel. Overall acceptability, glossiness, stickiness, hardness, flavor, and color were evaluated and compared to determine whether or not there were changes on consumer choice for acceptability. Brand A and brand B were not significantly different in their overall acceptability, moisture content, flavor, or color (p > 0.05), but they were significantly different for glossiness, stickiness, and hardness. Brands A and C were significantly different for all the attributes (p < 0.05). In the brand awareness test, brands A and B were not significantly different in their liking scores for all the attributes (p > 0.05). Brand C had significantly lower liking scores for overall acceptability, glossiness, stickiness, hardness, and moisture content than the other brands (p < 0.05). When comparing the liking scores for all the attributes with those of the blind test, the scores of the brand awareness test were slightly higher. For brand A, there were changes in its liking scores for overall acceptability, flavor, and glossiness (p < 0.05). However, brands B and C had brand awareness effects for all the attributes (p < 0.05).

• 성인간호학회지
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• 제20권1호
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• pp.55-64
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• 2008

Purpose: The purpose of this study was to identify the effect of Meridian pressure on the functions of upper extremities and discomfort of ADLs of hemiplegic patients. Methods: The research design was a nonequivalent control group, non-synchronized design. Subjects were 35 hemiplegic patients who were hospitalized at L Oriental Medical Hospital; 18 for the experimental group and 17 for the control group. The experimental group was given meridian pressure for 10 minutes daily for 2 weeks. The data were analyzed by SPSS 12.0 program. The ${\chi}^2$-test and t-test were used for the two groups' homogeneity, and t-test was used for the hypothesis test. Results: Manual muscle test, ROMs of wrist extension, elbow flexion, and shoulder extension of the experimental group increased compared to the control group. Shoulder pain and index finger circumference of the experimental group decreased compared to the control group. The experimental group showed to have less discomfort of ADLs than the control group. Conclusion: The study results verified that meridian pressure is effective for improving the functions of hemiplegic patients' upper extremities as well as reducing discomfort of ADLs.

• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2006년도 학술발표대회 논문집
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• pp.93-100
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• 2006

The failure of hydraulic hose assemblies is caused by the impulse pressure and repetitive motions of bending and stretching (flexing) used at high pressure pipe in the form of bursting Since it takes long time to observe the bursting for life analysis, we can reduce test time by the method of applying the Knockdown stress which is equivalent to 70% of initial bursting pressure on rubber hose assemblies with maintaining the failure mode equally In this study, after scale parameter, shape parameter, and acceleration factor by preforming the impulse pressure test until the hose bursts, and finally analyzed the accelerated life.