• 한국지하수토양환경학회지:지하수토양환경
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• 제14권2호
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• pp.33-44
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• 2009

본 연구의 목적은 국내 폐광산 지역 광미 등과 같은 비소 오염토양을 효과적으로 정화할 수 있는 생물학적 기술과 물리화학적 기술을 연계한 통합 기술을 개발하는 것이다. 이를 위해 폐광산이 송천 광산에서 비소를 다량 함유하고 있는 광미를 채취하여 비소와 중금속 함량을 정량적으로 분석하고 광미의 다양한 물리화학적 특성과 광물조성 등를 파악하였다. 그리고 광미 내 존재하는 비소와 중금속 종들의 존재형태별 상대함량을 분석하여 각 원소들의 용출성과 이동도를 예측하기 위하여 연속 추출법을 이용하였다. 이러한 광미와 광미내 존재하는 비소 및 중금속 오염물질의 기본적인 지구화학적 분석 자료를 바탕으로 비소의 생용출 (bioleaching)에 대한 컬럼실험을 수행하였다. 그리고 생용출과 전기동력학적 공정을 연계한 통합공정으로 비소를 제거한 실험을 실시하여 전기동력학 단일공정만 적용했을때와의 비소의 제거효율을 비교하여 통합공정의 적용 가능성을 평가하였다. 연구결과, 동일한 조건에서44일간 운전하였을 때 전기동력학 공정만을 개별적으로 적용했을 ��와 생용출(28일)과 전기동력학 (16일) 기술을 연계한 통합공정을 적용했을 ��의 비소 제거효율은 각각 57.8%와 64.5%로 나타났다. 그리고 생용출 (28일)에 의한 비소 제거효율은 11.8%정도로 상대적으로 매우 낮게 나타나서, 생용출은 비소를 제거하기 위한 공정이라기보다는 비소의 이동도를 증가시키는 공정으로, 이후 연계하여 적용되는 전기동력학적 공정에 의한 비소의 제거효율을 향상시키는 것으로 판단된다. 특히 전기동력학 공정을 단독으로 적용했을 때보다 생용출 공정을 연계했을 때 비소의 제거 속도가 두 배 이상으로 증가하는 것을 알 수 있었다. 이러한 결과는 비교적 경제적인 생용출 공정을 충분히 적용한 후 전기동력학적 공정을 적용하게 된다면, 비소의 제거효율 분만 아니라 제거속도 또한 향상된다는 것을 뒷받침해 줌으로써 두 기술을 연계한 통합공적의 적용 가능성과 향상성을 입증한다고 하겠다.

• 대한환경공학회지
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• 제27권9호
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• pp.989-994
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• 2005

본 연구에서는 활성탄 흡착, 오존 단독, 오존/활성탄 혼합공정을 이용하여 부식산을 처리하고 부식산의 처리효율을 $UV_{254}$와 DOC를 통해 살펴보았으며, 부식산의 분해특성은 분자량 크기분포의 변화와 활성탄 표면변화를 통해 관찰하였다. 각 공정에서의 DOC 제거효율을 살펴본 결과, 활성탄 흡착공정은 약 19%, 오존 단독공정은 38%이었으나, 오존/활성탄 혼합공정에서는 약 80%로 활성탄 흡착공정과 오존 단독공정의 DOC 처리효율을 합한 것보다 훨씬 높아, 혼합공정을 도입함으로써 시너지 효과를 얻을 수 있는 것으로 나타났다. 기리고 $UV_{254}$ 감소율 역시 오존/활성탄 혼합공정에서 가장 크게 나타났다. 오존/활성탄 혼합공정에서 활성탄은 고유의 흡착제 역할뿐만 아니라 흡착된 유기물과 오존의 접촉을 촉진시키는 반응자리를 제공하는 역할을 하는 것으로 사료된다. 각 공정에서의 분자량크기분포 변화를 살펴본 결과, 활성탄 흡착공정에의 분자량 크기분포는 반응 전후에 큰 차이가 없었으며, 오존 단독공정에서는 30 kDa 이상의 분자량이 반응시간 10분 이후에는 거의 감소하지 않고 일정하였으나, 0.5 kDa 이하의 저분자량은 초기 4.8%에서 120분 처리시 12.3%로 증가하였다. 한편 오존/활성탄 혼합공정에서는 120분 처리시 30 kDa 이상 분자량이 초기 36.3%에서 3.9%로 뚜렷하게 감소하였으며, 0.5 kDa 이하의 저분자량은 초기 4.8%에서 40.1%로 크게 증가하였다.

• 산업경영시스템학회지
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• 제34권2호
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• pp.76-84
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• 2011

To meet the needs of customer, manufacturing companies are diversifying product making methods. In order to adapt to changes, companies are trying to find a new manufacturing system. In this research, MTS (Make to Stock) and MTO (Make to Order) production methods are simulated using ARENA and the results are compared and analyzed to find a better system. As a result, by combining the advantages of MTS and MTO system, a hybrid production system is developed. The hybrid model is analyzed to verify that it is better than the existing two models, which is MTS and MTO model. The statistic results of output analyzer show that a new system helped to increase production rate and decrease work in process inventory. The hybrid model proved that it contains the merits of MTO production method and MTS production method.

• 기술혁신연구
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• 제15권2호
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• pp.83-102
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• 2007

This study extends the existing method of Technology Forecasting with Data Envelopment Analysis (TFDEA) by incorporating a ranking method into the model so that we can reduce the required number of DMUs (Decision Making Units). TFDEA estimates technological rate of change with the set of observations identified by DEA(Data Envelopment Analysis) model. It uses an excessive number of efficient DMUs(Decision Making Units), when the number of inputs and outputs is large compare to the number of observations. Hence, we investigated the possibility of incorporating CCCA(Constrained Canonical Correlation Analysis) into TFDEA so that the ranking of DMUs can be made. Using the ranks developed by CCCA(Constrained Canonical Correlation Analysis), we could limit the number of efficient DMUs that are to be used in the technology forecasting process. The proposed hybrid model could establish technology frontiers with the efficient DMUs for each generation of technology with the help of CCCA that uses the common weights. We applied our hybrid model to forecast the technological progress of main battle tank in order to demonstrate its forecasting capability with practical application. It was found that our hybrid model generated statistically more reliable forecasting results than both TFDEA and the regression model.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.163-166
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• 2003

Laser-Induced Thermal Imaging (LITI) is a laser addressed patterning process and has unique advantages, such as high-resolution patterning with over-all position accuracy of the imaged stripes within 2.5 micrometer and scalability to large-size mother glass. This accuracy is accomplished using real-time error correction and a high -resolution stage control system that includes laser interferometers. Here the new concept of mixed hybrid system which complement the advantages of small molecular and polymeric materials for use as an OLED; our system can realize the easy processing of polymers and high luminance efficiency of recently developed small molecules. LITI process enables to pattern the stripes with excellent thickness uniformity and multi-stacking of various functional layers without using any type of fine metal shadow mask. In this study, we report a full-color hybrid OLED using the multi-layered structure of small molecular/polymeric species.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.292-294
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• 2006

The aluminum Subframe for automobile chassis part was developed using hybrid process, i.e. extruforming, press stamping and MIG welding. To achieve a 30 % weight reduction compared with convensional steel subframe keeping satisfactory performance, the design of cross-section of extruforming part was introduced, then forming simulation was performed and the final design was determined. In addition, we tried to estibilish optimun aluminum welding conditions for good penetration depth and few pore defect, finally the prototype of aluminum subframe was assembled using MIG welding method. Furthermore, we will adapt this technology to mass production and apply to the other chassis parts.

• 한국생산제조학회지
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• 제22권5호
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• pp.871-878
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• 2013

Roll-to-roll (R2R) hot embossing systems have been developed and are widely used in various industrial domains. These systems press and heat flexible films between a press roll and a back-up roll, as said films pass through the two rolls. In previous studies, a heating roll was used for heating. However, in this study, a hybrid roll for R2R hot embossing is conceptualized and developed. This R2R system can be used for generating fine patterns on large and continuous films. The hybrid roll of our system can cool and heat the films simultaneously, thus affording greater flexibility in process design. Thermal and structural analyses were performed for developing the hybrid roll. In addition, a hybrid roll was designed based on analytical results. Experiments were conducted for measuring the performance of the developed hybrid roll.

• 한국응용과학기술학회지
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• 제26권3호
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• pp.288-296
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• 2009

In this study, the silica-based hybrid material with high barrier property was prepared by incorporating ethylene-vinyl alcohol (EVOH) copolymer, which has been utilized as packaging materials due to its superior gas permeation resistance, during sol-gel process. In preparation of this EVOH/$SiO_2$ hybrid coating materials, the (3-glycidoxy-propyl)-trimethoxysilane (GPTMS) as a silane coupling agent was employed to promote interfacial adhesion between organic and inorganic phases. As confirmed from FT-IR analysis, the physical interaction between two phases was improved due to the increased hydrogen bonding, resulting in homogeneous microstructure with dispersion of nano-sized silica particles. However, depending on the range of content of added silane coupling agent (GPTMS), micro-phase separated microstructure in the hybrid could be observed due to insufficient interfacial attraction or possibility of polymerization reaction of epoxide ring in GPTMS. The oxygen barrier property of the mono-layer coated BOPP (biaxially oriented polypropylene) film was examined for the hybrids containing various GPTMS contents. Consequently, it is revealed that GPTMS should be used in an optimum level of content to produce the high barrier EVOH/$SiO_2$ hybrid material with an improved optical transparency and homogeneous phase morphology.

• 자동차안전학회지
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• 제13권4호
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• pp.20-25
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• 2021

This paper is the result of a research on hybrid tuning technology developed to improve the actual fuel efficiency and reduce emissions of in-use light-duty diesel trucks. In this study, a hybrid powertrain was constructed by inserting an electric motor between the diesel engine and manual transmission of an internal combustion engine vehicle and installing a battery. To verify the safety, a test was conducted based on the Korean tuning regulations. In particular, since there has been no case of tuning an internal combustion engine vehicle into a hybrid vehicle in Korea, it was necessary to carry out all procedures to receive tuning approval. The approval process consists of a technical review, safety verification test, and application for tuning approval. As a result, the test vehicle was approved for tuning because both the technical review and vehicle test results were suitable. Therefore, this study confirmed the safety of diesel hybrid tuning technology, and laid the foundation for the research and development of technologies to tune into an eco-friendly vehicle as well as the activation of related industries.

• 한국기계가공학회지
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• 제12권3호
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• pp.28-35
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• 2013

Micro electrical discharge machining (EDM) as a non-contact machining process is very effective for micromachining with a thin electrode because of its low machining reaction force. The micro-electrode machining device has the advantage of maintaining high precision through the whole processes and uses a feeding wire in the thin electrode tool manufacturing process. This study describes the design and evaluation of a micro-electrode machining device using optical photo-interrupter. The electrode was fabricated by reverse electrical discharge machining. The performance of designed system was evaluated to measure tension force according to feed speed of wire. This system for micro electrode fabrication proves the feasibility in the micro-EDM process of the micro holes and parts for industrial applications.