• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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• pp.285-292
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• 2002

A cluster tool for semiconductor manufacturing is an integrated device that consists of several single wafer processing modules and a wafer transport module based on a robot. The distributed module controllers are integrated by an inter-module communication network and coordinated by a centralized controller, called a cluster tool controller (CTC). Since the CTC monitors and coordinates the distributed complex module controllers for advanced process control, complex commuication messaging and services between the CTC and the module controllers are required. A SEMI standard, CTMC(Cluster Tool Module Communication), specifies application-level communication service requirements for inter-module communication. We propose the use of high-level fieldbuses, for instance. PROFIBUS-FMS, for implementing CTMC since the high-level fieldbuses are well suited for complex real-time distributed manufacturing control applications. We present a way of implementing CTMC using PROFIBUS-FMS as the communication enabler. We first propose improvements of a key object of CTMC for material transfer and the part transfer protocol to meet the functional requirements of modem advanced cluster tools. We also discuss mapping objects and services of CTMC to PROFIBUS-FMS communication objects and services. Finally, we explain how to implement the mappings.

• Journal of Advanced Marine Engineering and Technology
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• 제35권3호
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• pp.329-334
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• 2011

The cooling water circulation plates had been used to drop the temperature of refractory outside shell of common cooling system by using cooling plate or stave type. When they are attacked by surrounding gas, they are corroded and the water flows in the refractory due to leakage of water. So, the life of refractory material is shortened and changed due to the worse conditions of cooling system. The automatic sensing device for water leakage of cooling plate is developed to check the position of trouble by using the microprocessor system when cooling water leak and gas are flowed into the cooling plate through the leakage position. The flowed gas is detected in the micro-process system which delivers the detected position of cooling plate or stave to main control room through the wireless-radio relay station. This system can be possible to detect the position of cooling plate or stave against the water leakage part immediately and then deliver the signal to main control room by using the microprocessor system and wireless-radio relay station. This system will be developed in changing the working condition from manual system to unmanned auto alarm system.

• 말소리와 음성과학
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• 제3권1호
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• pp.35-43
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• 2011

The purpose of this paper is to evaluate the viability of employing the intonation exaggeration technique proposed in [4] in teaching English prosody to university students. Fifty-six female university students, twenty-two in a control group and the other thirty-four in an experimental group, participated in a teaching experiment as part of their regular coursework for a five-and-a-half week period. For the study material of the experimental group, a set of utterances was synthesized whose intonation contours had been exaggerated whereas the control group was given the same set without any intonation modification. Recordings from both before and after the teaching experiment were made and one sentence set was chosen for analysis. The parameters analyzed were the pitch range, words containing the highest and lowest pitch points, and the 3-dimensional comparison of the three prosodic features [2]. An AXB and subjective rating test were also performed along with a qualitative screening of the individual intonation contours. The results showed that the experimental group performed slightly better in that their intonation contour was more similar to that of the model native speaker's utterance. This appears to suggest that the intonation exaggeration technique can be employed in teaching English prosody to students.

• 한국산학기술학회논문지
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• 제21권10호
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• pp.48-54
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• 2020

과학기술의 급속한 발전 속도와 군용부품시장의 축소 등이 원인이 되어 부품단종이 증가하고 있다. 부품단종은 무기체계 총수명주기비용이 증가시키며 군 전투력 등에 큰 문제를 일으킬 수 있다. 따라서 부품단종으로 발생하는 대응비용을 절감하기 위해서는 사전 관리가 중요하며 사전관리 근간을 마련하기 위해 단종관련 정보를 관련자들이 공유할 수 있는 데이터베이스 구축이 되어야 한다. 효율적으로 데이터베이스를 관리하기 위해서는 주요 관리 항목을 선정하여 지속적으로 업무를 수행하는 것이 필요하다. 본 연구의 목적은 부품단종 관리 시스템에서 주요한 관리 항목을 도출하는 데 있다. 방위사업청 매뉴얼과 SD-22 등을 바탕으로 관리 항목을 선정하여 주요 관리항목을 AHP(Analytic Hierarchy Process) 기법을 통해서 분석하였다. 부품단종에 따른 영향성, 부품단종 확률, 부품단종 대응비용의 3가지 기준에 의해 관련된 세부 항목 15개로 계층화하였으며 9점 척도로 설문한 항목에 대해 각각의 가중치를 산출하였다. AHP 설문조사는 부품 관리 전문가 25명을 대상으로 실시하였고, AHP 설문결과 일관성비율이 0.1 초과인 것을 제외하였다. 그 결과 부품단종관리를 위한 유용한 항목을 도출할 수 있었으며 이에 대한 결과 해석 및 향후 발전방향을 제시하였다.

• 한국군사과학기술학회지
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• 제25권3호
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• pp.251-258
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• 2022

Infrared stealth technology used in aircraft is applied to reduce the infrared signal by controlling surface temperature and emissivity using internal heat sink, low emissivity material or metamaterial. However, there is one part of the aircraft where the use of this technology is limited, and that is the radome. Especially, radome should have transmittance for the specific radio frequency, therefore, common stealth technology such as emissivity control surfaces cannot be applied to radome surface. In this study, we developed metal nano-coating for infrared stealth which is applicable to radome surface. We designed slot-type pattern for frequency selective transmission in X-band, and also controlled thickness of metal nano-coating for long wavelength infrared emissivity control. As a result, our infrared stealth surface for radome has 93.2 % transmittance in X-band and various infrared emissivities from 0.17 to 0.57 according to nano-coatings thickness. Also, we analyzed infrared signature of radome through numerical simulation, and finally reduced contrast radiant intensity by 97.57 % compared to polyurethane surface.

• Journal of Welding and Joining
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• 제16권1호
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• pp.77-87
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• 1998

This paper deals with the effect of laser welding parameters on the weld formation. Thin steels for automotive application were prepared so as to be welded with high power carbon dioxide laser system. Major process parameters were position of focus and travel speed. The effect of shielding gas was also discussed by employing the high speed photometry. Test results showed that the optimal position of focus varied in accordance with the joint configuration; bead-on-plate, butt or lap welding. It was recommended that the position of focus for the lap welding be located at slightly inner part of the material to be welded. In this case, however, it was noticeable that the weld penetration ratio, d/t$_{0}$ dropped drastically at the critical region. Results also demonstrated that both the bead width and penetration reduced as the travel speed increased. The penetration ratio showed two distinct regions; stabilized zone at the lower range of the travel spped and sudden drop zone at the higher range of travel speed. Lower limit of the penetration for acceptable weld was proved to be about 90% of the parent metal thickness based on the physical properties of the weld. Mixed gas application for both the shielding of molten metal and laser induced plasma control was recommended as far as the penetration was concerned.d.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.804-819
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• 2003

It has been known that adenine is a very important material in living cells. Because, adenine is a member of nucleotide base, so it takes part in DNA, RNA and ATP synthesis. There are many reports that adenine participated in ingredients, especially DNA, RNA, NADH and ATP, affect on the cell. As well adenosine, conjugated adenine to glycoside, was known to anti-wrinkle compound. But there is no report whether adenine shows a good effect on the skin, especially anti-wrinkle. So, in this study, we tested whether adenine affects cell proliferation, collagen synthesis, collagenase synthesis inhibition in human dermal fibroblasts. In addition, we performed clinical study with adenine cream. Cell proliferation effect was tested by MTT assay. Collagen and collagenase synthesis were measured by Immunoassay with ELISA kit. Clinical study was performed by IECK according to KFDA Functional Cosmetic method. The results of cell proliferation show that 10$^{-6}$ ~10$^{-8}$ ％ of adenine increases cell proliferation about 50 ％ compare with non-treated control. At 10$^{-7}$ ~10$^{-10}$ ％, adenine increases type I collagen synthesis about 50％, decreases type I collagenase about 22％ compare with non-treated control. The results of clinical study show that 0.05％ adenine treated group reduces wrinkle significantly compare with placebo treated group. Therefore adenine may be a new anti-wrinkle candidate, through increases cell proliferation and collagen synthesis dramatically. And it decreases collagenase synthesis. So adenine could be used as a new anti-wrinkle agent.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.729-732
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• 2004

An experimental and numerical approach has been carried out for to see the noise characteristics of a circular diamond saw. The noise level measurement result for the several kinds of shanks shows us that the noise level reduction in high frequency range could be an effective way to control the noise problem. Sandwich type shank whose center part is laminated with a low Young‘s modulus material greatly reduces the noise level. The noise level for the shank where several curve shaped slits are provided in the circumferential direction is reduced considerably too. The response spectrum analysis by the FEM shows us to be an alternative for predicting the noise characteristics of the shank.

• 대한원격탐사학회지
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• 제34권6_1호
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• pp.1033-1039
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• 2018

우리나라는 매년 여름철마다 태풍과 집중호우가 함께 발생하는 홍수로 인해 인명 및 재산피해가 발생한다. 특히 임진강 유역은 급경사와 좁은 하도인 상류부와, 낮은 평지인 하류부로 되어 있어 홍수에 취약한 지형을 가지고 있다. 게다가 북한 지역의 임진강 상류에 위치한 대형 댐인 황강댐에서 여름철 마다 무단방류로 인하여 피해가 발생하였다. 이런 홍수 피해를 방지하기 위해 우리나라에서는 2010년 군남홍수조절지를 건설하여 홍수피해를 방지하고 있다. 하지만 홍수조절지의 건설 이후에도 홍수조절능력이 황강댐의 최대 저수량의 20%밖에 미치지 못한다. 이에 이 연구에서는 경기북부지역의 집중호우시 발생할 수 있는 홍수 피해 위험지역을 산정하기 위하여 LAHARZ_py 프로그램을 이용하여 피해예상지역을 산출하였다. 그 결과 군남홍수조절지의 홍수조절능력을 넘는 황강댐의 방류가 발생할 시에 경기도 연천군과 파주시에 피해가 예상되었다. 추후 이 연구는 홍수 피해를 대비하기 위한 자료로 유용할 것으로 판단된다.

• 접착 및 계면
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• 제10권2호
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• pp.77-83
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• 2009

생체적용 센서 코팅 재료로서 polydimethylsiloxane (PDMS)를 선정하였으며 합성 및 성형과정에서 용출될 수 있는 잔류 독성 물질의 세포독성을 확인하고자 하였다. ISO 10993-5, Biological evaluation of medical devices-Part 5 : Tests for in vitro cytotoxicity (의료기기의 생물 안정성 평가-제5부: 세포 독성 시험-체외시험)를 통하여 세포 독성 평가를 실시하였다. 양성 대조군으로 organo-tin을 사용하였으며 음성 대조군으로 혈청이 포함되지 않은 RPMI 1640배지를 사용하였다. 고체 시료의 표면적에 대하여 $125{\mu}L/cm^2$가 되도록 혈청이 포함되지 않은 RPMI 1640 배지를 용기에 첨가하였으며 $38^{\circ}C$를 유지하며 일정시간 동안 추출하였다. 세포 독성 평가는 1) NIH 3T3 fibroblast 단일세포층을 형성한 후 추출물을 첨가하는 방법과 2) 세포와 함께 추출물을 넣어 배양하는 방법을 동시에 시행하였다. 세포 형태학적인 변화 관찰과 MTT (tetrazolium dye, 2-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) 시험법에 의한 세포 활성 측정을 병행함으로써 고체 시료로부터 추출된 물질의 세포독성 여부와 고체시료의 표면에 대한 세포의 감응성도 함께 관찰할 수 있었다.