• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.751-756
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• 2009

In the perspective of saving energy in buildings, the high performance of insulation and air tightness for improving the heating and the cooling efficiency, has brought economically positive effects. However, these building energy saving technologies cause the lack of ventilation, which is the direct cause of increasing the indoor contaminants, and is also very harmful to the residents, because they spend over 90% of their time indoors. Therefore, the ventilation is important to keep the indoor environment clean and it can also save the energy consumption. In this study, a HEPA type nano ceramic filter is designed as a passive ventilation system to collect airborne particles and to supply fresh outdoor air. The double layer filter, which has $30{\mu}m$ in diameter at the conditions of 10wt% of concentration and 3kV/cm of the electric intensity, is produced by electrospinning. The filtration coating technology is confirmed in the solution with $SiO_2$ nano particles using polymer nano fibers. Also double layer filters are coated with $SiO_2$ nano particles and finally the porous construction materials are made by sintering in the electric furnace at $200{\sim}1400^{\circ}C$. The efficiency is measured 96.67% at the particle size of $0.31{\mu}m$, which is slightly lower than HEPA filter. However the efficiency is turned out to be sufficient.

• 한국의류학회지
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• 제33권11호
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• pp.1683-1695
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• 2009

This study analyzes the production process of eight domestic companies that manufacture scuba diving suits for men with an emphasis on the level of consumer satisfaction in scuba diving suits purchases. One hundred fifty questionnaires were distributed and a total of 140 usable data were coded for further statistical analysis that includes descriptive statistics (frequency and ${\chi}^2$ test) through SPSSWIN 17.0. The results show that a majority of the domestic scuba diving suit companies were either small, manufactured products under original equipment manufacturer (OEM) brands, or were involved in the import business. Many of these companies have developed a local sizing system derived from a company database of customer sizing. As a result, different companies have different sizes that lead to confusion and complication among consumers in selecting the correct size for scuba diving suits. The results indicate that most high-priced diving suits are made of imported fabrics because they had superior quality, fitness, and thickness compared to domestic brands. The degree of consumer satisfaction with scuba diving suits was found to be low in comfort, stuffiness, and activity. Respondents indicated that they felt a little tightness in circumstances such as bust, wrist, and thigh in measurements of circumstances. On the other hand, the respondents showed a high degree of satisfaction with body fitness in scuba diving suits. Further research will clarify a standardized sizing system and develop patterns suitable for Korean men's scuba diving suit body sizes.

• 터널과지하공간
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• 제23권4호
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• pp.319-325
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• 2013

본 연구의 목적은 지하공동 내에 고압 압축공기를 저장하는 경우 발생할 수 있는 리스크를 평가하는 것이다. 문헌 조사와 CAES의 특성에 대한 연구를 통해 CAES 지하 저장 공동 개발과 관련된 리스크 요인을 선정하였다. 대분류 리스크 요인으로 기획 설계단계, 시공단계, 운영 유지관리단계의 3개를 고려하였으며, 중분류 리스크 요인으로 8개를, 소분류 리스크 요인으로 총 24개의 리스크 인자들을 선정하였다. 전문가 설문을 통해 얻어진 자료를 분석하기 위하여 AHP 기법을 적용하였으며 리스크 상호 간 상대적 중요도를 평가하였다. 해석 결과 대분류에서는 운영 유지관리단계 리스크, 중분류에서는 품질 안전 관련 리스크, 소분류에서는 압축공기 저장용 내조시스템의 기밀성 확보 실패가 가장 큰 리스크로 평가되었다.

• 한국세라믹학회지
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• 제45권12호
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• pp.802-806
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• 2008

A proper sealant for low temperature SOFCs should show zero or low leak rates to avoid direct mixing of the fuel and oxidant gases or leakage of fuel gas during the operation of SOFCs. Furthermore, it should be chemically and/or mechanically stable in both oxidizing and reducing environments and chemically compatible with other fuel cell components. In the present work, we developed a novel compressed seal gasket of glass-based composite reinforced with ceramic particulate particles, which can efficiently control the viscous flow of glass matrix as well as the crystallization of glass phase. This novel sealing gasket showed excellent gas tightness under very low compressive load which would be suitable for the operation of SOFCs in the temperature range $600{\sim}650^{\circ}C$.

• 한국수소및신에너지학회논문집
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• 제28권6호
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• pp.675-682
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• 2017

New government, the market for stationary fuel cell systems in domestic is expected to expand in line with the policy for expanding new and renewable energy. In order to promote and expand the domestic market for stationary fuel cell systems, it is required to do research and develop for cost reduction and efficiency improvement technologies through the localization of BOP. In this study, the safety performance including the power consumption, flow rate, noise and air-tightness of the domestic fuel booster blower and the foreign fuel booster blower was evaluated and the performance improvement of the domestic blower was confirmed. As a result of the power consumption measurement and the flow rate according to the back pressure of the A company 2nd prototype and B company, the values were 73 W, 27 LPM, and 55 W, 25 LPM. These results are attributed to the improvement of performance through design changes such as CAM angle and diaphragm material.

• 성인간호학회지
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• 제14권3호
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• pp.459-469
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• 2002

Purpose: Experience of chest pain may be different in women from that of men and this discrepancy may cause misdiagnosis of angina contribute to mortality by this disease in women. The purpose of this study was to analyze the characteristics of chest pain and responses to the symptoms in women. Method: A content analysis was conducted with interviewed data obtained from women who underwent the treadmill test Result: Seven major categories were identified from this content analysis: attributes of chest pain; accompanied symptoms; precipitating factors; relief strategies; family support; communication with physicians; and effects of chest pain on their lives. Characteristics of pain were described as heaviness, tightness, heating sensation, tearing, and others. Duration and intensity of pain varied in a wide range. Radiating pain presented in 9 patients, and the locations of radiation were throat, neck, shoulder arm and fingers. Women tended not to respond actively to their chest pain, and didn't get appropriate support either from their family or from their physicians when they reported chest pain. Conclusion: Women express non-typical as well as typical patterns of pain when they experience chest pain. Clinicians have to consider the variability of symptoms when they assess women with suspicions of angina.

• 한국멀티미디어학회논문지
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• 제17권11호
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• pp.1363-1373
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• 2014

In this study, a hybrid multi-cup electric cupping system (HMECS) was proposed, based on the ancient cupping method. HMECS consisted of several cups that could be used simultaneously to treat different areas of the patient's body. Each cup was equipped with its own pump and pressure-monitoring system. Moreover, the vacuum pressure of the cups was controlled using fuzzy logic. Through automated control of the vacuum pressure, long-term relief of muscle tightness was achieved. To develop a scientific foundation for this alternative treatment, we compared the VAS(Visual Analog Scale) and ODI(Oswestry Disability Index) scores from conventional basic cupping to the VAS and ODI scores for our proposed HMECS. The improvement rate in the VAS and ODI scores using HMECS after three treatments was higher than that achieved by basic cupping. These results, combined with the convenience offered by enhanced IT capabilities, should increase the popularity of this device among an aging society, and facilitate the opportunity to further explore the potential of Oriental medical practices.

• 대한물리의학회지
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• 제10권4호
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• pp.1-7
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• 2015

PURPOSE: The purpose of this study was to compare the effects of cross-body stretching (CBS) and modified cross-body stretching (MCBS) on the range of motion (ROM) of glenohumeral joint (GHJ) in healthy subjects. METHODS: Thirty subjects were randomly assigned to 1 of 2 groups: CBS group without stabilization of scapula (n=15) and MCBS group with stabilization of scapula (n=15). We measured horizontal adduction and internal rotation ROM of GHJ in pre- and post-intervention. The data were analyzed using the analyses of covariate (ANCOVA) and least significant difference (LSD) post hoc tests (p=.05). RESULTS: In the post-intervention, the MCBS group had a significantly greater increase in horizontal adduction ROM (mean ${\pm}$ SD, $11.46^{\circ}{\pm}0.83^{\circ}$) compared to the CBS group ($7.81^{\circ}{\pm}0.83^{\circ}$) (p=.007) and a greater increase in internal rotation ROM ($62.27^{\circ}{\pm}0.74^{\circ}$) compared to the CBS group ($59.20^{\circ}{\pm}0.74^{\circ}$) (p=.004). CONCLUSION: A single session application of an MCBS provides immediate more improvements in both horizontal adduction and internal rotation ROM than CBS. These results suggest that application of MCBS with stabilization of scapula may be a more useful to gain ROM of GHJ than CBS without stabilization of scapula.

• 한국정밀공학회지
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• 제15권8호
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• pp.17-25
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• 1998

Aluminum alloys have low density, relatively high strength and yield strength, good plasticity, good machinability, and high corrosion and acid resistance. Therefore, they are suitable for large containers for the food, chemical and other industries. Large containers are often bodies of revolution consisting of shell courses, stiffening rings, heads and other elements joined by annular welds. Larger containers have longer welds and require greater leak-tightness and higher weld mechanical properties. The LNG tank consists of aluminum plates with various sizes, so its construction should by divided by several sections. Moreover, each section has its own sub-section consisted of several aluminum plates. To guarantee the quality of huge LNG tank, therefore, the precise control of plate dimension should by urgently needed in conjunction with the appropriate selection of process parameters such as cutting speed, depth of cut, rotational speed and so on. In this paper, a manufacturing system was developed to implement automatic circular tracking in height direction and automatic circular interpolation in depth of cut direction. Also, the neural network based on the backpropagation algorithm was used to predict the cutting quality and motor load related with the life time of the developed system. It was revealed that the manufacturing system and the neural network could be effectively applied to the bevelling process and to predict the quality of machined area and the motor load.

• 공업화학
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• 제3권4호
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• pp.639-648
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• 1992

시멘트 수화물(CH)을 모르타르 콘크리트용 방수제 또는 고무 플라스틱용 충전제로 활용하기 위하여 스테아린산(SA)으로 처리하고 FT-IR, TGA, SEM, XRD, 접촉각층정기 등을 이용하여 CH-SA compound의 결합특성과 발수성을 측정하고, CH-SA compound를 레미탈에 사용하여 레미탈의 방수성을 알아 본 결과는 다음과 같이 요약된다. 1) 시멘트 수화물에 스테아린산을 2.0%이상만 처리하면 물레 대한 접촉각이 $120^{\circ}$이상으로 증가되면서 강한 발수성을 나타낸다. 2) 시멘트 수화물에 처리된 스테아린산은 스테아린산염 형태로 시멘트 수화물 표면에 고정된다. 3) 시멘트 수화물에 스테아린산을 5~10%처리한 CH-SA compound를 레미탈 중량의 3~6%정도 사용하면 레미탈의 압축강도는 5%정도 증가되며, 흡수비와 투수비는 각각 25%이하로 격감되어서 우수한 방수성을 나타낸다.