• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.152-152
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• 2008

Micro probe with Ni-Co tip was designed. Unit processes for fabricating the micro probe were developed. We are investigated the micro probe tip using by Ni-Co alloy. One-step and three-step needle was fabricated by plating process, CMP, and photolithography process. The plating thickness was varied by current density and time. Futher data will be extract by different process conditions.

• 대한기계학회논문집A
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• 제26권11호
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• pp.2415-2420
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• 2002

In the present study, a new anchor design was proposed to minimize the initial deflection of micro multi-layer cantilever beam with step-up structure, which is a key component of thin film micro-mirror array. It is important to minimize the initial deflection, caused by residual stress, because it reduces the performance of the actuation. Theoretical and experimental studies were conducted to examine the cause of the initial bending deflection. It was found that the bending deflection at the anchor of the cantilever beam was the primary source of initial deflection. Various anchor designs were proposed and the initial deflections for each design were calculated by finite element analysis. The analysis results were compared with experiments. To reduce the initial deflection a secondary support was added to the conventional structure. The optimal shapes were obtained by simulation and experiment. It was found from the analysis that the ratio or horizontal and vertical dimensions of secondary support was the governing factor, which affected the initial deflection.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.97-100
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• 1998

In this paper, micro step driving method is used for the high performance motion control and low vibration and low noise in an X-Y axis soldering machine for factory automation. The improvement of the electrical and mechanical driving characteristic of a stepping motor is achieved by applying microstep driver.

• Restorative Dentistry and Endodontics
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• 제30권4호
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• pp.283-293
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• 2005

본 연구는 합착 술식에 따른 레진 합착제의 상아질에 대한 미세전단결합강도를 비교 연구하여 이중 접착 술식의 유용성을 평가하고자 시행되었다. 합착 술식은 전통 합착 술식과 이중 접착 술식, 임시 합착제는 Propac과 Freegenol, 상아질 접착제는 All-Bond 2, One-Step, Clearfil SE Bond를 사용하였다. 이중 접착 술식을 적용한 군에서만 상아질 접착제 처리 후, 모든 시편에 임시 합착제를 도포하였다. 이후 임시 합착제를 제거하고 상아질 접착제 적용 후 유리봉에 레진 합착제를 도포하여 상아질 면에 접착하였다. 미세전단결합 강도를 측정하고 접착 계면을 주사전자현미경으로 관찰하였다. 1. 전통 합착 술식이 이중 접착 술식보다 높은 미세전단결합강도를 보였으나 통계학적 유의 차가 없었다. 2. Freegenol이 Propac보다 높은 미세전단결합강도를 보였으나 유의차가 없었다. 3. 미세전단결합강도는 이중 접착 술식 을 적용한 경우 Clearfil SE Bond가 One-step, All-Bond 2보다 유의성 있게 높았으나(p<0.05) One-step, All-Bond 2 간 유의차는 없었다. 4. 전자현미경 소견에서 All-Bond 2와 One-Step을 사용한 군은 길고 수많은 resin tag가 관찰되었다. 본 연구 결과 전통 합착 술식과 비교하여 이중 접착 술식의 우수함을 확인하지 못하였다.

• 전력전자학회논문지
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• 제11권5호
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• pp.447-453
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• 2006

본 논문은 전류 제어기를 가지는 마이크로 스텝 제어를 통하여, 뛰어난 5상 스텝 모터 구동드라이버를 제안하였다. 시스템의 최소화 구성을 위하여 아날로그 전류 제어기를 제안하였다. 이로 인해 가격 절감 효과를 가지고 왔으며, 기존 상용 제품과 비교하여 소음 및 발열의 감소도 확인하였다. 본 시스템을 위치 제어 로봇에 적용하여 위치제어 적용 가능성 및 제안된 아날로그 제어기와 구동 드라이버의 타당성을 검증하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 추계학술대회 논문집
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• pp.254-258
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• 2009

In this paper, the low frequency vibration forming system is developed for micro-patterns formation on the metal substrate. many researchers have studied about micro-forming technologies such as micro deep drawing, press forming, forging, extrusion etc. for the formation of precise micro-patterns on the surface of metal substrates, multi-step forming process must be used to improve qualifies of the deformed patterns. Since the low frequency vibration forming system could easily deform the surface of metal substrates, several steps of multi-step forming process should be removed by using the low frequency vibration forming system. In order to find optimal process conditions, we have carried out low frequency vibration forming process with varying the vibration frequency from 110Hz to 500Hz.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1517-1521
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• 2007

On this study, technical aspects were reviewed to drill a series of micro holes (${\phi}$0.10) over 200 within a few micron tolerance in diameter and position on the stainless steel material. Dedicated tools & jigs were designed and manufactured and optimum cutting conditions were found. On this micro hole drilling process, guide drill and step feeding were applied to help chip discharge, prevent drill breakage and finally improve the accuracy of positioning and roundness. The processing results indicated that most holes are distributed within a few micron tolerance in diameter and position intervals.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.25-30
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• 2011

In this paper, we analyzed the electrical characteristics with Micro-cracks in Photovoltaic module. Micro cracks are increasing the breakage risk over the whole value chine from the wafer to the finished module, because the wafer or cell is exposed to mechanical stress. And The solar cells have to with stand the stress under out door operation in the finished module. Here the mechanical stress is induced by temperature changes and mechanical loads from wind and snow. So, we experimentally analyze the direct impact of micro-cracks on the module power and the consequences after artificial aging. The first step, we made micro-cracks in PV module by mechanical load test according to IEC 61215. Next, PV modules applied the thermal cycling test, because micro-cracks accelerated aging by thermal cycling test, according to IEC61215. Before every test, we checked output and EL image of PV module. As the result of first step, we detected little power loss(0.9%). But after thermal cycling test increased power loss about 3.2%.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권7호
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• pp.409-416
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• 2004

This paper presents the selection method o( the input current wave forms for the thrust force ripple of linear pulse motor (LPM). We have developed and tested a prototype 2-phase 4-poles LPM with the permanent magnet and its control driver. To obtain the thrust performance curve of LPM, the performance curve at the air gap and the thrust are calculated and estimated by the analytical method on the base of the magnetic equivalent circuit and the finite element method. And, the thrust characteristics at the static operation state are analyzed and experimented with the respect to the input wave forms such as the rectangular, the triangular micro-step and the sine micro-step wave forms to investigate the thrust ripple and the vibration effects of LPM.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (B)
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• pp.262-264
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• 2005

MicroRNA는 약 22 nucleotide 길이로, 세포질에서 유전자의 전사 후 조절 기능을 맡는 small RNA의 한 종류이다. MiRNA는 긴 전사체인 pri-miRNA에서 Drosha에 의해 절단 되어 핵 밖으로 나가 최종 Dicer에 의해 성숙된다. 하지만, 아직까지 이 효소들이 pri-miRNA를 잘라내는 3차 구조상의 메커니즘을 이해하지 못하고 있다. 본 연구에서는 완숙한 miRNA 이중나선이 약 2 회전을 이루게 된다는 정보를 바탕으로, Drosha가 붙는 miRNA stem구조의 dinucleotide step 파라미터를 유전 알고리즘을 이용하여 추정한다. 추정된 파라미터로부터 실제 miRNA들의 3차구조를 예측할 수 있으며, 3차 구조상의 Drosha의 절단 메커니즘을 이해하는데 도움을 줄 것이다.