• 상하수도학회지
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• 제25권5호
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• pp.767-775
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• 2011

In this study we verified if the electro-coagulation process can treat properly the nitrate and fluoride that are not removed well in the conventional small water treatment plants which usually employ chlorination and filtration only. As we gave a change of electrode material and gap-distance between electrodes, removal efficiency of the nitrate and fluoride was determined by electro-coagulation process which were equipped with aluminum and stainless steel (SUS304) electrodes. In addition, electrode durability was investigated by determination of electrodes mass change during the repetitive experiments. Removal efficiency was great when aluminum was used as an anode material. Nitrate removals increased as electric density and number of electrodes increased, but fluoride removal was less sensitive to both parameters than nitrate. After 10 minutes of contact time with the current density from $1{\times}10^{-3}$ to $3{\times}10^{-3}A/cm^{2}$, nitrate and fluoride concentration ranged from 9.2 to 1.2mg/L and from 0.02 to 0.01mg/L, which satisfied the regulation limits. Regardless of the repeating number of experiments, removal efficiency of both ions were almost similar and the change of electrode mass ranged within ${\pm}$0.5%, indicating that the loss of the electrode mass is not so much great under the limited circumstances.

• Journal of Chest Surgery
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• 제36권6호
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• pp.436-438
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• 2003

다발성 원발성 폐암은 동시성 원발성 페암과 이시성 원발성 폐암으로 나눌 수 있는데 두 가지 경우 모두 드물게 발견되는 폐암의 일종이다. 본원에서는 최근 동시성 원발성 폐암과 이시성 원발성 폐암을 각각 1예씩 수술 치험하였기에 보고하는 바이다.

• 노동경제논집
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• 제36권2호
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• pp.37-65
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• 2013

본 연구는 임금함수의 비모수적 추정을 통해 근속급 및 경력급의 근로자집단별 특징을 비교해 보고, 2000년대 후반의 변화를 분석하였다. 근속 프리미엄이 가장 높은 집단은 대기업 고졸 숙련직으로 나타났으며, 비정규직, 영세업체 근로자는 근속급과 경력급이 미미하였다. 노조 유무는 근속급과 경력급에 큰 영향을 미치지 않았다. 또한 대기업 중심으로 경력에 대한 보상이 전반적으로 강화되었다. 한편, 비모수 모형설절 검정 결과 Mincer 임금함수의 설정 오류로 인한 편의는 근속 30년차 근속급 추정치의 경우 -25~29%, 경력급 추정치는 -42~6%였다.

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2005년도 GIS/RS 공동 춘계학술대회
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• pp.105-110
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• 2005

텔레매틱스 서비스는 컴퓨팅, 통신, 컨텐츠, 측위 및 자동차 산업의 융합 기술로서, 개별적으로 존재하는 서로 다른 기술의 통합을 통해 자동차 내에서 수행되는 새로운 서비스를 창출하고 있다. 텔레매틱스로 인하여 자동차는 이동 수단으로의 역할뿐만 아니라 제3의 디지털 라이프 공간이 되어 편리한 운전과 모바일 오피스 및 여가를 즐기는 공간이 되고 있다. 본 논문에서는 텔레매틱스를 위하여 개발되는 기술의 기능 성능 품질의 시험과 통합 운영을 위한 텔레매틱스 테스트베드의 국내외 기술 및 구축 동향에 관하여 기술한다.

• 한국레이저가공학회지
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• 제8권3호
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• pp.27-30
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• 2005

Nowadays, most automotives companies are making use of laser welding in car body assembly shop. But even though laser welding is better than resistance spot welding in many points, its application has been limited to special technology for manufacturing. The paper introduces in the field of remote welding system (RWS) to improve the process efficiency of laser welding. Positioning time of RWS between welding stitches is dramatically reduced to zero. It is a kind of solutions to generalize laser welding in mass production. This RWS consists of fiber laser, industrial robot and 3-axis scanner.

• 천문학회보
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• 제40권2호
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• pp.30.2-30.2
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• 2015

Abell 2744 is a giant merging cluster, called the Pandora's Cluster, at the redshift of z=0.308 (corresponding to a distance of 1270 Mpc). Taking the advantage of the deep high resolution images in the Hubble Frontier Field program, we study the properties of compact stellar systems including globular clusters and ultracompact dwarfs (UCDs) as well as dwarf galaxies in this cluster. We find a rich population of globular clusters and UCDs in Abell 2744. The spatial distribution of these objects is consistent with the mass map derived from lensing analysis, while showing a significant offset from the X-ray map of hot gas. The faint end of the luminosity function of the galaxies in the red sequence is fit by a flat slope, showing no faint upturn. We discuss these finding in relation with the origin of UCDs, formation of red sequence dwarf galaxies, and formation of the Pandora's cluster.

• 대한안전경영과학회지
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• 제2권4호
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• pp.103-112
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• 2000

This research aims at the improvement of the manufacturing productivity of . kitchen furniture industry. W company deals with the orders of 2 types - the one is the batch order for mass production, and the other is the order of a customized single set. But, because the company has a single manufacturing system appropriate to mass production despite of the above 2 types-orders, the problems of increasing work-in-process, throughput time and material handling time were resulted in, and the overall productivity was generally low. We proposed a new material handling method to substitute the traditional one, the rearrangement of facility layout, and the introduction of a proper outsourcing method. This research results in about 80% increase in production quantity in the same period.

• 대한산업공학회지
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• 제27권3호
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• pp.305-314
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• 2001

In this paper, we construct an automatic evaluation system of psychological feeling for corporate identity (CI) symbol mark based on a fuzzy neural network technique. The system is modelled by trainable fuzzy inference rules with several input variables (qualitative and quantitative design components of CI symbol mark) and a single output variable (consumer's feeling). The back propagation learning algorithm, which is a conventional learning method of multilayer feedforward neural networks, is used for parameter identification of the fuzzy inference system. The learning ability to train data and the generalization ability to test data are evaluated for the proposed evaluation system by computer simulations.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (A)
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• pp.637-639
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• 2005

정보 통신 기술의 빠른 발전으로 인해 차량이 단순한 운전 공간이 아닌 다양한 서비스를 이용할 수 있는 복합적 환경으로 변모해 강에 따라 텔레매틱스라는 말이 더 이상 낯선 말이 되지 않고 있다. 이에 세계의 여러 나라들은 이와 관련된 IT 산업에서의 경쟁력 확보를 위해 핵심 기술을 더욱 연구 개발하고 있다. 본 논문에서는 텔레매틱스 기술을 발전시키고, 관련 산업을 더욱 활성화 시키기 위하여 현재 진행중인 제주 텔레매틱스 시범 서비스에 대해 소개한다. 제주 텔레매틱스 시범 서비스는 향후 관련 기술의 향상과 국외 텔레매틱스 기술에서의 주도권 확보를 통하여 한국이 텔레매틱스 강국이 되는 것을 목표로 하고 있다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2006년 추계학술발표대회 개요집
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• pp.45-47
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• 2006

Lightweight design, safety, vibration, energy absorption capability can no longer achieve without adhesive bond joint. Base on those concepts and cost reduction, adhesive bond FEM model development has been done. The FEM analysis and experiments were conducted in this study. Crash condition is 143 Kg Hammer weight and unit meter Height. and then These test results were used to develop resonable FEM model. To estimate which FEM model is resonable, compare hybrid joint specimen experiment results with FEM analysis results. Conclusively this study achieves optimization bonding model related crash and adhesive bond jointed hat profile crash characters.