• 전산구조공학
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• 제17권3호
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• pp.53-56
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• 2004

• 한국산학기술학회논문지
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• 제15권12호
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• pp.6980-6985
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• 2014

레이저 직접묘화방법을 이용하여 절연기판($SiO_2$)위에 미세전도성패턴을 제조하였다. 레이저 유도증착공정은 레이저빔이 금속박막에 조사되면 레이저 빔의 빛 에너지가 금속박막에 흡수되어 열에너지로 바뀌면서 열전도에 의한 열분해반응으로 기판위에 증착이 일어난다. 본 논문에서는 금속박막위에 폴리머 코팅을 하여 레이저 직접묘화공정을 적용하여 미세패턴과 3차원 마이크로 구조물 제조에 관한 연구를 수행하였다. 평균 증착율은 전반적으로 레이저출력이 높을 수록 선형적으로 증가하고, 빔 스캔 속도가 감소할수록 증착율은 증가한다는 것을 확인하였다. Polymer 코팅층을 이용하여 미세전극을 증착하여 비저항값을 측정하여, 코팅층을 사용한 경우의 전기전도도가 코팅을 하지 않은 경우보다 약 3배정도 향상되는 것을 확인할 수 있었다.

• 영어어문교육
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• 제16권4호
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• pp.133-152
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• 2010

There is disagreement, among researchers, on the benefits of corrective feedback on L2 learners' written output. Some scholars advocate the usefulness of corrective feedback while some claim that error correction is ineffective and even harmful. So far, however, research outcomes cannot settle this debate. Based on this debate, this study examines whether there is a difference among diverse types of feedback on the effects of L2 learners' writing improvement. This study found that teacher's direct feedback was more effective than any other types of feedback on the effect of participants' writing improvement. In particular, teacher's direct feedback helped their improvement on grammar, mechanics, and form. Among the types of peer feedback, self-correction was the most effective. In teacher feedback, form-focused feedback had more effects than content-focused feedback, but no difference with regard to peer feedback. In addition, teacher's content-focused feedback was more effective than peer's content-focused feedback. Overall, in all types of feedback, teacher feedback was more effective than peer feedback. However, direct (form-focused) feedback was the most effective in teacher feedback, and self-correction in peer feedback. The least effective feedback in both teacher and peer feedback was indirect (form-focused) feedback, which is simple underlining of errors.

• 한국도서관정보학회지
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• 제45권1호
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• pp.125-147
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• 2014

본 연구의 목적은 학교도서관에서 읽기와 쓰기를 통합 지도 할 수 있는 학습독서 전략을 개발하여 제안하는 것이다. 읽기와 쓰기 전략은 인지과정에 기반을 둔 절차와 관련된 간접전략과, 절차의 성공적 수행을 도와주는 직접전략으로 나눌 수 있다. 따라서 읽기와 쓰기를 통합한 학습독서 전략을 교수설계모형에 해당하는 간접전략과 모형의 각 단계별 구체적인 실행 방안을 담은 직접전략으로 구성하였다. 본 연구에서는 학습독서가 프로그램 형태로 운영될 수 있는 상황을 고려하여 간접전략인 기본 모형을 준비-설계-운영-평가와 같이 4단계로 설정하였다. 그리고 읽기와 쓰기를 통합 지도하는 학습독서 운영 단계는 '주제정하기-목차쓰기-탐구하기-집필하기-수정하기-출판하기'와 같이 6단계로 구성하였다. 또한 각 운영 단계별로 읽기와 쓰기 활동을 구체적으로 도와줄 수 있는 직접전략을 제시하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1889-1892
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• 2003

The fabrication of micro-size patterning on alumina substrate is generated by laser direct writing, which has high precision and selectivity of various laser beam energies. The depth and width of patterns is affected by laser parameter such as laser power, scan rate. Through the chemical and mechanical polishing Pd seeds was effectively got rid of alumina substrate for selectivity electroless Ni plating. Thermal treatment is good method for changing electrical property of conductor line, because the treatment can control of the grain size.

• 한국레이저가공학회지
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• 제10권2호
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• pp.17-24
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• 2007

We have studied a laser direct writing lithography(LDWL). This is more important to apply to micro patterning using UV laser. We demonstrate the possibility of LDWL and construct the fabrication system. We use Galvano scanner to process quickly micro patterns from computer data. And laser beam is focused with $F-{\theta}$ lens. AZ5214 and SU-8 photoresist are chosen as experimental materials and a kind of well-known positive and negative photoresist respectively. Laser ablation mechanism depends on the optical properties of polymer. In this paper, therefore we investigate the phenomenon of laser ablation according to the laser fluence variation and measure the shape profile of micro patterned holes. From these experimental results, we show that LDWL is very useful to process various micro patterns directly.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.479-480
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• 2013

• 한국광학회:학술대회논문집
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• 한국광학회 2004년도 제15회 정기총회 및 동계학술발표회
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• pp.116-117
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• 2004

• 한국레이저가공학회:학술대회논문집
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• 한국레이저가공학회 2002년도 추계학술발표대회 논문개요집
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• pp.91-94
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• 2002

• 한국전기전자재료학회논문지
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• 제13권11호
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• pp.969-975
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• 2000

Laser direct writing of micro-patterned copper lines has been achieved by pyrolytic decomposition of copper formate films (Cu(HCOO)$_2$.4$H_2O$), as a metallo-organic precursor, using a focused CW Ar$^{+}$ laser beam (λ=514nm) on PCB boards and glass substrates. The linewidth and thickness of the lines wee investigated as a functin of laser power and scan speed. The profiles of the lines were measured by scanning electron microscope (SEM), surface profiler ($\alpha$-step) and atomic force measured by scanning electron microscope (SEM), surface profiler ($\alpha$-step) and atomic force microscopy (AFM). The electrical resistivities of the patterned lines were also investigated as a function of laser parameters using probe station and semiconductor analyzer. We compared resistivities of the patterned copper lines with these of the Cu bulk. Resistivities decreased due to changes in morphology and porosity of the deposit, which were about 3.8 $\mu$$\Omega$cm and 12$\mu$$\Omega$cm on PCB and glass substrates after annealing at 30$0^{\circ}C$ for 5 minutes.s.