• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1220-1225
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• 2009

A manipulator is operated for the motion of mechanical hands or arms. When a cup including liquid inside is shifted by a manipulator, it is important to know how a free surface of the liquid moves. In this study, non dimensional parameters have been found that affect the rise of the free surface in a cup moving with constant acceleration. The non-dimensional parameters are the dimensionless time, the ratio of inertia effect to viscous effect (the Reynolds number), aspect ratio of the liquid inside the cup and the acceleration ratio (the Froude number). Through this study, the height of the free surface rise in a cup has been predicted and the detailed velocities in the liquid have been examined. Generally, the maximum rise of the free surface is dependent on the Reynolds number and Froude number strongly, but on the aspect ratio weakly. However, the influence of the aspect ratio on the maximum rise of the free surface is not negligible in the range of 10 < Re < 100.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.370-370
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• 2012

Feature size of Cu interconnects keep shrinking into several tens of nanometer level. For this reason, the Cu interconnects face challenging issues such as increase of electro-migration, line-width dependent electrical resistivity increase, and gap-filling difficulty in high aspect ratio structures. As the thickness of the Cu film decreases below 30 nm, the electrical resistivity is not any more constant, but rather exponential. Research on alloying with other elements have been started to inhibit such escalation in the electrical resistivity. A faint trace of Al added in Cu film by sputtering was reported to contribute to suppression of the increase of the electrical resistivity. From an industrial point of view, we introduced cyclic metal organic chemical vapor deposition (MOCVD) in order to control Al concentration in the Cu film more easily by controlling the delivery time ratio of Cu and Al precursors. The amount of alloying element could be lowered at level of below 1 at%. Process of the alloy formation was applied into gap-filling to evaluate the performance of the gap-filling. Voidless gap-filling even into high aspect ratio trenches was achieved. In-depth analysis will be discussed in detail.

• 복식문화연구
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• 제21권2호
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• pp.234-245
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• 2013

The modern fashion was developed the basis on the western dress structure and its historical flow was continued until today. Particularly, the Britain has coexised the unique cultural identity in the aristocratic high culture and rebellious tendency of the subculture so it is necessary to the consideration about whole culture in order to grasp the British fashion identity. The purpose of this study was shown the methodological framework of the culture identity research of one country through the background of this formation of culture and process high culture and subculture study by analysis the culture identity in the today's Britain. Also, the purpose of this study that it draws whether the feature of the British fashion shows up as any aspect in this culture identity. The range of this study subdivides and considers with the imperialism, industrial revolution, aristocratism, union nations, and geographical aspect as the island country into the economy, politics, society, and natural characteristic about the Englishness and the notion of British culture then it draws the dichotomy of the British fashion through the culture identity formed in this society cultural background with both sides in the high culture and subculture aspect.

• 한국수소및신에너지학회논문집
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• 제21권5호
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• pp.364-374
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• 2010

Design of a reformer consisting of combustion chamber and reforming chamber was investigated for a 1 kW and a 5 kW polymer electrolyte membrane fuel cell (PEMFC), respectively, using the computational fluid dynamics (CFD). First, the 1kW reformer was considered to obtain the reliability of the numerical study. It was modeled, calculated and compared with experimental data. Second, the 5kW reformer was considered for a geometric study. Three tip sizes (35, 40, and 45 mm) and five aspect ratios was selected. It was found that the optimum was at tip sizes of 40 and 45 mm, at aspect ratios of -10% and -20% of the standard length.

• KIEAE Journal
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• 제10권1호
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• pp.57-64
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• 2010

Electric energy is indispensible of the development of the industrial and living sector. Among the energy sectors, the building area shares 20% of the produced electric power in Korea. As we plan to supply the apartment, we need to forecast the required amount of the electric energy and supply the infrastructure to apartment for the lighting, cooling. Nonetheless, it is not easy to forecast the required amount of the electric energy, considering the management aspect, building physical aspect and social-geographic aspect. In this paper, it studied the estimation model of the electric energy, reflecting the affecting variables such as total area, number of household, geography and so on. The estimation model is proposed in 3-types which explained in central heating, individual heating and district heating, and each type have two estimation model, reflecting the affecting variable and corelation between variables to eliminate the muticolinearity. The unit of electric energy consumption per area and year is similar in three heating type and the results are as follows; the central heating is $34.446kWh/yr{\cdot}m^2$, individual type is $35.756446kWh/yr{\cdot}m^2$ and district heating is $34.285446kWh/yr{\cdot}m^2$.

• 한국지역지리학회지
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• 제9권4호
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• pp.461-480
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• 2003

본 논문은 대구를 사례로 신도시화 과정을 경제, 정치, 사회문화, 환경 그리고 공간적 측면으로 나누어 고찰하였다. 경제적으로 대구의 산업구조는 제조업 중심에서 서비스산업으로 바뀌었으며, 산업의 특화정도는 조립금속과 정밀 광학분야의 비중이 높아지고 있으나 여전히 섬유산업위주의 단선적 산업구조의 틀을 벗어나지 못하고 있다. 정치적으로 지방자치제의 실시로 지역 간의 경쟁이 첨예해지는 상황에서, 대구 지방정부는 전반적으로 지역여건을 성장주의적 분위기로 이끌어가면서, 약화되는 지역 투자나 생산기능을 확충하기 위해 민 관 학의 연계체계를 구성하여 지역의 현안 문제를 해결하는 경향을 보이고 있다. 사회적으로 구도시 체제에서는 대규모 하드웨어 시설에 많은 투자를 하였으나 신도시 체제에서는 사회문화적 소프트웨어시설에 많은 투자를 하게 되었다. 문화적으로는 기존의 축제가 행정 편의적이고 가시적 축제였다면, 현재의 축제는 시민들과 함께 할 뿐만 아니라 지역경제 활성화에 도움을 주는 축제로 변하고 있다. 환경적으로 지방자치제가 본격적으로 시작되면서 산업기반시설과 혐오시설의 입지로 인해 지방자치단체간의 가치 및 이해관계를 둘러싼 갈등문제가 심각하게 표출하고 있다. 마지막으로 신도시화 과정에서 주거팽창과 공간구조의 불균형적 이용은 토지이용의 비효율성을 야기하고 있다. 이런 무계획적인 도시의 외연적 확산은 직주분리와 사람들의 이동의 필요성을 증대시켰으며 이는 에너지 과소비적 도시공간구조를 가져왔다.

• 한국전자거래학회지
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• 제20권2호
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• pp.107-123
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• 2015

초연결사회를 구현하는 핵심 기술이자 정부와 기업의 새로운 신성장동력으로써 사물인터넷이 전 세계적으로 주목 받고 있다. 하지만 새로운 비즈니스 기회로써 받는 주목과는 대조적으로 기술적인 관점이 아닌 비즈니스 관점에서의 사물인터넷에 대한 학계의 연구는 미비한 수준에 머무르고 있으며, 사물인터넷 시장에 대한 객관적인 이해 또한 부족하다. 따라서 사물인터넷 서비스 시장의 실태를 파악하고, 신사업 기회를 포착 할 수 있는 연구가 필요하다. 본 연구는 사물인터넷 서비스 시장 활성화를 위한 기반연구로서 사물인터넷 시장에 대한 객관적인 통계 수집을 위한 사물인터넷 서비스 분류체계를 제시한다. 사물인터넷 서비스 분류체계는 사물인터넷 산업에 대한 포괄적인 분석을 위해 서비스 목적(IoT Purpose), 서비스 제공자(IoT Player), 서비스 영역(IoT Domain)의 관점으로 구성하였다. 문헌조사를 통해 총 117개의 사물인터넷 서비스를 수집하여 분류체계에 대입해 봄으로써 분류체계의 유용성을 검증하였고, 분류결과를 통해 사례 통계 기반의 사물인터넷 서비스 시장의 동향을 제시하였다. 본 연구는 향후 사물인터넷 서비스 활성화를 위한 기반 연구로써 활용될 수 있을 것으로 사료된다.

• Design & Manufacturing
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• 제17권4호
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• pp.33-41
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• 2023

Excessive use of plastic bottles contributes to a significant environmental issue due to the high volume of plastic waste generated. To address this, efforts are needed to reduce the weight of plastic bottles. However, indiscriminate weight reduction may compromise the essential rigidity required for plastic bottles. Extensive research on rib shape for pressure vessels are exists, but there is a few research of rib shapes to enhance the stiffness of plastic bottles. The following results were obtained from the analyses conducted in this study. 1) Among the rib cross-sections of square, trapezoid, and triangle, the buckling critical load of PET bottles with square-shaped ribs is improved by about 14% compared to the buckling critical load of PET bottles without ribs. 2) The buckling critical load is improved by about 18% when a square-shaped rib with an aspect ratio of 0.2 is applied, compared to the buckling critical load of the bottle without the rib. 3) When longitudinal and transverse square ribs were applied to the axial direction of the PET bottle, the buckling critical load was improved by about 32% and 58% compared to the buckling critical load of the PET bottle without ribs, respectively, indicating that applying longitudinal ribs is effective in reinforcing the stiffness of PET bottles. 4) When 14 transverse ribs were applied, the maximum improvement was about 48% compared to the buckling critical load of the plastic bottle without ribs. 5) When 3 longitudinal ribs were applied on each side, the maximum improvement was about 76% compared to the buckling critical load of the bottle without ribs. Therefore, it was concluded that for effective stiffness reinforcement of a 500ml square bottle with a thickness of 0.5mm, 3 square-shaped ribs with an aspect ratio of 0.2 should be applied in the longitudinal direction relative to the axial direction of the bottle.

• 한국의류학회지
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• 제36권5호
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• pp.512-522
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• 2012

This study examined the work environment and wearing conditions of industrial protective clothing in shipbuilding workshops. It also investigated the relationship between the wearing sensation of industrial protective clothing and overall comfort, according to work process. In addition, the work posture according to work process was evaluated based on ergonomic factors. The wearing rate of industrial protective clothing was 73.3%, 66.7%, and 60.1% for workers engaged in welding, grinding, and painting, respectively. The harmful work environment factors, listed from most harmful to least harmful, were found to be high temperature pyrogens, noxious fumes, organic solvents, UV rays, and heavy dust. The aspect of wearing performance of industrial protective clothing that was most related to user dissatisfaction was poor sweat absorbency. In terms of the correlation between the overall comfort and the wearing sensation of industrial protective clothing, the satisfaction was low shown in orders of physiological comfort, sensual comfort, and movement comfort.

• 경영과정보연구
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• 제7권
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• pp.381-400
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• 2001

Our country has been encountered with severe economic depression since IMF loan(1997). Korean economic system should be reformed according to the globalization and the world industrial trends based on adavanced technologies and skills. Todays the venture business should be considered to be the alternative of recovering Korean economy and increasing highly estimated values. Generally speaking, the venture business is defined as a new business with high risk-high return with new technical entrepreneurship. This treatise suggests the activating alternatives of the venture business in Korea. These alternatives are suggested as follows. First, several measures to incruit excellent technicians are suggested. These measures includes incruitment of parttime technicians, application of cooperative program of education training unemployees, the stock option system, a stock-sharing plan for the employees, etc. Second, in the financial aspect, activation of the foundation investment company, activation of the COSDAQ market, strengthening of technology security are suggested. Third, in the technical development aspect, amplification of inauguration assistant center, construction of technology accumulative network, etc. These measures will contribute to the development of Korean economy and the welfare of Korean people.