• 복식
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• 제39권
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• pp.91-98
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• 1998

This paper is to study the development background of casual Korean clothes through the consideration of the style change of traditional clothes. The purpose of this study is to present the method for the settlement of casual Koran clothes as everyday clothes and to present the direction which casual Koran clothes follow in the future. The development. The development backgrounds of casual Korean clothes are as followings. 1) the self-awakening for the importance of national culture. 2) practical aspects 3) the change of life style accompanied with economic growth 4) the development of mass media Casual Korean clothes in the future should be studied and developed in following aspects. 1) practical aspects by developing design for easy activity 2) environmental aspects by natural dyeing which is harmless to human body and the nature 3) emotional aspects by regarding traditional beauty as importance 4) color sense aspects according to scarcity of as form change of the Korean clothes 5) production aspects by mass production of ready-made clothes not order clothes 6) diplomatic aspects as folk costume which is corresponding with international trend 7) scientific aspects by developing many patterns according to various bodies 8) economic aspects by low price through the mass cultivation of natural materials 9) fashionable aspects by subdividing traditional clothes to ceremonial clothes, everyday clothes, working clothes.

• 한국수소및신에너지학회논문집
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• 제25권3호
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• pp.264-270
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• 2014

Fuel cell technology is the most representative area of alternative energy field on vehicle industry according to the limitation of petroleum resources. In recent years, the technology of fuel cell vehicles has made rapid progress, Hyundai Motor Company (HMC) reached to mass production of the Tucson ix hydrogen fuel cell vehicles first in the world. In addition, HMC is accelerating the development of hydrogen fuel cell buses, which have a number of advantages for hydrogen infrastructure and mass transport personnel. In this study, we examined potential of the commercialization through the demonstration of hydrogen fuel cell buses. As a result, we identified that the mass-production possibility of FCB has high potential and HMC's technology will lead to fuel cell bus industry.

• 한국전기전자재료학회논문지
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• 제23권12호
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• pp.978-982
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• 2010

For mass information transfer, the optical communication using optic fiber has been widely used. Especially, in the field of medical image, the large data is digitalized based on the standard image and it is used for telemedicine with this method. Therefore, to transfer the large amount of data fast and effectively POF (Plastic Optical Fiber) can be used and the development of optic connector for connection between POFs is very important. In this study, for stable optical coupling of POF optic fiber Ferrule and Sleeve were designed and produced by considering the bond stability and the insertion loss according to the physical contact and roughness profile was evaluated. As a result of examining the insertion loss by physical contact method of two optic fibers, it showed the loss was about 1.895dB. According to the results from studying the condition of grinding section for POF mass production, the mass production condition was established as POF profile roughness of 6nm and the loss of 0.2dB or lower by controlling the film size and time step by step.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.430-433
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• 2009

The development of large-scale environmental friendly livestock complex in the reclaimed tideland is one of different alternatives to increase the competitiveness of internal livestock industry against an international opening markets as DDA and FTA in agricultural field. Recently, it is possible to introduce an environmental friendly livestock complex in the reclaimed tideland by an amendment of the acts for agricultural land. However more studies that are on the basis of nitrogen and phosphorus mass balance need to preserve the agricultural environments as the quality of agricultural water and soil in rural area. In this study, the reference for feasibility study is Whaong reclaimed tideland which located at Whaseong city, Gyeonggi Province, and a basic concept of environmental friendly livestock complex is the production of forage crops with the supply of liquid fertilizer and the production of bioenergy such as biogas by the recycling of pig slurry as a resource. The mass balance of nitrogen based on between forage crops such as maize, barley and liquid fertilizer supplied at the reclaimed tideland, and also it was estimated an economical efficiency as anaerobic digestion plant for treating pig slurry of $100m^3/day$ introduce in an environmental friendly livestock complex.

• 천문학회지
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• 제51권2호
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• pp.37-48
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• 2018

Massive stars blow powerful stellar winds throughout their evolutionary stages from the main sequence to Wolf-Rayet phases. The amount of mechanical energy deposited in the interstellar medium by the wind from a massive star can be comparable to the explosion energy of a core-collapse supernova that detonates at the end of its life. In this study, we estimate the kinetic energy deposition by massive stars in our Galaxy by considering the integrated Galactic initial mass function and modeling the stellar wind luminosity. The mass loss rate and terminal velocity of stellar winds during the main sequence, red supergiant, and Wolf-Rayet stages are estimated by adopting theoretical calculations and observational data published in the literature. We find that the total stellar wind luminosity due to all massive stars in the Galaxy is about ${\mathcal{L}}_w{\approx}1.1{\times}10^{41}erg\;s^{-1}$, which is about 1/4 of the power of supernova explosions, ${\mathcal{L}}_{SN}{\approx}4.8{\times}10^{41}erg\;s^{-1}$. If we assume that ~ 1 - 10 % of the wind luminosity could be converted to Galactic cosmic rays (GCRs) through collisonless shocks such as termination shocks in stellar bubbles and superbubbles, colliding-wind shocks in binaries, and bow-shocks of massive runaway stars, stellar winds might be expected to make a significant contribution to GCR production, though lower than that of supernova remnants.

• 한국기계가공학회지
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• 제17권1호
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• pp.48-56
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• 2018

Due to the growing concerns of energy resource depletion and environmental destruction, the mass production of microalgae has been studied. The scale-up of a photobioreactor (PBR) is required for the mass production of biomass. In this paper, the geometric parameters and oxygen transfer rate (OTR) are considered, to scale up a flat panel photobioreactor (FP PBR). The PBR is designed using the goal-driven optimization (GDO) method to accomplish the scale-up. The local sensitivity of each output parameter with respect to the input parameter is analyzed through the design of experiment (DOE), and the design candidates are evaluated with the screening sampling method. The volumetric mass transfer coefficient is measured by the dynamic method.

• 정보저장시스템학회논문집
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• 제6권1호
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• pp.37-40
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• 2010

Fresnel lens is a kind of refractive optical lens with various advantages. It has nearly flat shaped optical lens that has small mass. Fresnel lens has number of applications in the compact optical systems. Recently, demands of high quality Fresnel lens for small size optical systems such as illumination units, compact imaging systems, display units, information storage systems, optical detecting units had increased rapidly. Conventional manufacturing process of high quality Fresnel lens is direct machining. However, it is not suitable for mass production because of high cost and long cycle time. Replication method can provide cost effective mass production process. However, there are various issues about replication of Fresnel lens. Fresnel lens has number of sharp blade shape prism. In the replication process, this blade shape causes defects that can affect optical efficiency. In this study, replication processes; injection molding process and UV imprinting process, were developed and evaluated using Fresnel lens that has maximum pattern height of $250\;{\mu}m$ and aspect ratio of 1.5.

• 천문학논총
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• 제30권2호
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• pp.169-171
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• 2015

NGC147 and NGC185, paired satellites of the Andromeda galaxy, possess the same order of mass and analogous structures, but they show different star formation and different amounts of interstellar gas and dust. Therefore, we present the first reconstruction of the star formation history of NGC147 and NGC185. Asymptotic Giant Branch stars are highly evolved stars that are brightest in K-band. This maximum K-band magnitude is related to the birth mass of stars. As a result, we have found a 9.9 Gyr old single star formation epoch for NGC185 followed by relatively continuous star formation. NGC147, however, has passed through two star formation episodes; one is as old as ~6 Gyr and the other is as recent as ~850 Myr. Asymptotic Giant Branch stars are also important dust factories; by fitting Spectral Energy Distributions to observed near and mid infrared data for each star, we were able to measure the dust production rates of individual stars; on order of $10^{-5}M_{\odot}yr^{-1}$. Hence, we estimate the total mass entering the interstellar medium to be $1.06{\times}10^{-4}M_{\odot}yr^{-1}$ and $2.89{\times}10^{-4}M_{\odot}yr^{-1}$ for NGC147 and NGC185.

• Design & Manufacturing
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• 제16권4호
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• pp.40-45
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• 2022

The EV electric vehicle market is growing rapidly worldwide. An electric vehicle means a vehicle that uses energy charged through an electricity source as power. The precision of the press is important to mass-produce the drive motor, which is a key component of the electric vehicle. The size of the driving motor is increasing, and The size of the mold is also growing. In this study, the precision of large high-speed presses for mass production of driving motors was measured. A study was conducted on the measurement method of press and the analysis of measurement data. A drive motor is a component that transmits power by converting electrical energy into kinetic energy. EV driven motors have key material properties to improve efficiency. The material properties are the thickness of the material. As a method for improving performance, use a 0.2mm thin steel sheet. Mold is also becoming larger. As the mold grows, the size of the high-speed press for mass production of the driving motor is also increasing. Also, the precision of the press is the most important because it uses a thin iron plate material. So the importance of large press precision is being emphasized. In this study, the effect of large high-speed press structure on precision was verified

• 자원리싸이클링
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• 제32권6호
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• pp.25-33
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• 2023

이차전지 산업의 성장과 함께 이차전지의 생산량과 사용량의 급격한 증가가 예상되며, 이와 맞물려 생산 스크랩을 포함한 폐이차전지의 재활용에도 많은 관심과 노력이 이루어지고 있다. 그동안 폐이차전지 재활용은 양극재를 중심으로 많은 노력이 이루어졌지만, 핵심 광물의 공급망 확보와 재활용률 향상을 위해 음극재의 재활용에도 많은 관심이 기울이기 시작하였다. 음극재의 주성분인 흑연 분석을 위해 석탄의 함량을 측정하는 공업분석이 활용될 수 있지만, 기존의 석탄 분석에 활용되는 공업분석 방법은 블랙 매스의 구성 성분 간의 상호작용으로 인해 정확한 측정이 불가능하다. 이에 본 연구에서는 산소 분위기에서 950℃까지의 온도 상승에 따른 블랙 매스 각 성분의 열중량 변화를 측정하였다. 측정 결과 양극재의 경우에는 양극재에 포함된 바인더와 도전재의 산화에 의한 약 5%의 질량 감소 이외에는 질량 변화가 측정되지 않았으며, 음극재의 경우에는 약 2%의 바인더에 의한 질량 감소 이외에는 모두 고정 탄소에 의한 질량 감소로 측정되었다. 또한 블랙 매스에 함유될 수 있는 금속 전극(Al, Cu)들은 온도가 상승함에 따라 산화되어 질량이 증가하는 현상이 관찰되었다. 다양한 혼합 비율의 양극재/음극재 혼합 시료의 열중량 변화 측정 결과는 양극재와 음극재 각각의 열중량 변화를 통해 계산할 수 있는 예측값과 유사한 결과를 보여, 블랙 매스의 열중량 특성 변화를 통해 음극재의 함량 도출이 가능할 수 있음을 확인하였다.