정부의 공공정보 개방 활용 업무의 데이터거버넌스 체계 정립 연구

최완일(Choi, Wan Il) 한국IT서비스학회 2011 한국IT서비스학회 학술대회 논문집 Vol.2011 No.9

'스콜라' 이용 시 소속기관이 구독 중이 아닌 경우, 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

본 논문은 공공부문의 정보공개활용업무의 데이터거버넌스 체계의 정립을 데이터 관리의 베스트프랙티스와 IT거버넌스의 모델을 활용하여 검토한다. 일반적인 데이터거버넌스의 주된 영역에 더하여 특별히 업무의 특성에 기반한 위험관리와 규제 준수의 측면과 semantic 기술 및 social media 등 신기술의 이용과 관련된 추가적인 이슈들을 도출하여 거버넌스의 프레임워크를 구성함으로서 향후 공공부문의 데이터거버넌스 정책 수립 및 시행 시의 개선 방향을 제시한다.

일정광량 방식의 광자주사현미경 제작

김지택,최완해,조재홍,장수,김달현,구자용,정승태,Kim, Ji-Taek,Choi, Wan-Hae,Jo, Jae-Heung,Chang, Soo,Kim, Dal-Hyun,Koo, Ja-Yong,Chung, Seung-Tae 한국광학회 1999 한국광학회지 Vol.10 No.3

가열인장(heating and pulling)방법을 이용하여 개구부 직경이 약 100nm 이하인 광섬유 탐침을 제작하였으며, 이를 이용하여 일정광량 방식의 광자주사현미경을 제작하였다. 광섬유 탐침을 물체에 미세하게 접근시켜서 물체면을 주사하기 위하여 원통형 PZT(piezoelectric transducer)를 x-y-z의 3부분으로 나누어 z축의 미세접근 및 1.43$\mu\textrm{m}$ $\times$ 1.76$\mu\textrm{m}$의 면적을 x-y축으로 주사할 수 있는 3차원 PZT 주사기를 제작하였다. 그리고 광섬유 탐침에서 검출되는 에바네슨트라의 광량이 항상 일정하도록 전자적인 되먹임 회로에 의한 광섬유 탐침이 1$\lambda$ ($\lambda$ 는 입사파장임) 이하의 근접장 영역에서 물체로부터의 높이가 일정하도록 하였다. 그리고 이렇게 제작된 일정광량 모드의 광자주사 현미경을 이용하여 정상파 형태의 에바네슨트파를 측정하였다. We made sharp optical fiber tips with less than 100 nm diameter by using the heating and pulling method with a good repetition and fabricated the photon scanning tunneling microscope (PSTM) using constant intensity mode. The 3-dimensional PZT (Piezoelctric transducer) scanner made of a long PZT tube is consisted of three divided parts, that is, a pair of $\pm$ x and a pair of $\pm$y scanning parts and a z scanning part for the fine approach and scanning. The scanning dimension is 1.43 $\mu\textrm{m}$$\times$1.76 $\mu\textrm{m}$. The height of a optical tip to maintain a constant height within $1/{\lambda}_0$ (${\lambda}_0$ is the incident wavelength) from surface of a specimen to a optical tip is controlled automatically by using the electric feedback circuit. The 3-dimensional shape of standing evanescent waves generated on the surface of a dove prism was measured successfully by using the constant intensity mode PSTM.

자동변속기용 토크 컨버터 성능 최적화에 관한 연구

최완(Wan Choi),이진수(Jin-Soo Lee),장재덕(Jae-Duk Jang),주인식(In-Sik Joo) 한국자동차공학회 2005 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2005 No.5_1

To improve vehicle performance, development of the torque converter matching to advanced engine performance is essential. The improvement of the torque converter’s performance could be optimized by modifying geometry of 3 elements of the torque converter. The impeller and turbine of automotive torque converters are usually made of stamped sheet metal parts. Any geometry modification of the impeller or turbine would be very expensive because of tooling cost. In contrast, the stator is usually made of aluminum die-casting. Torque converter modifications are limited to the stator only in order to reduce the manufacturing cost. By the Computational Fluid Dynamics, the variation of stator shapes were analyzed and designed. To verify the accuracy of CFD, performance test was done with samples. In comparison of analysis with test result, both shows similar pattern through overall speed ratio.

CCITT 언어들에 기반을 둔 소프트웨어 개발환경

최완(Wan Choi),송영기(Young-Kee Song),김영시(Young-Si Kim) 대한전자공학회 1992 대한전자공학회 학술대회 Vol.1992 No.4

토크 컨버터 토러스 형상 변화에 따른 유동 특성에 관한 연구

최완(Wan Choi),권의섭,장영기(Young-gi Jang),장재덕(Jae-duk Jang),주인식(In-sik Joo) 한국자동차공학회 2009 한국자동차공학회 부문종합 학술대회 Vol.2009 No.4

The torque converter is a very complex turbo machine. Its geometry is highly three-dimensional, the working fluid is viscous oil, and it operates under a wide range of flow conditions. However, its hydrodynamic design technology has advanced very little during the past serveral decades. The design procedure has been based greatly on the use of the cut-and-try approach. The use of such an approach may satisfy the design requirements in terms of diameter, axial length, and torque capacity factor, but it may never lead to optimized design for any given application. In addition, it has been proven to be too costly and time consuming. The current design tools need to be upgraded in order to significantly advance the hydrodynamic design technology. A review of the technology needs in the areas of internal flow, torus design, and performance is presented. At first, the three dimensional internal flow fields and the physical mechanisms of the internal flow losses are described. Secondly, case analyses of a torus shape, using potential flow and viscous flow by the finite element method, are shown. Lastly, technology is required to develop an optimum performance model is presented.

유한 요소법을 이용한 토크 컨버터 섭동각 예측에 관한 연구

최완(Wan Choi),송재훈(Jae-Hoon Song),Hideaki Kosuge,장재덕(Jae-Duk Jang),주인식(In-Sik Joo) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

The lock-up clutch in the torque converter can improve highly the efficiency of power transfer from an engine by locking up with the transmission gears directly at a high speed instead of fluid coupling. Upon locking up, NVH problems take place due to shudder, friction material characteristics, and so on. Front cover taper angle, friction material, contact surface roughness and damper characteristics are important design parameters for improvement of drivability. Front cover taper angle is based on the surface pressure between front cover and friction facing. In this study, the pressure distribution of the contact surface is analyzed by finite element method. Also, we propose design optimization method for torque converter taper angle.

자동변속기 차량의 연비 향상을 위한 토크 컨버터 댐퍼 시스템 개발

최완(Wan Choi),한관수(Kawnsoo Han),장재덕(Jaeduk Jang),주인식(Inski Joo) 한국자동차공학회 2010 한국자동차공학회 학술대회 및 전시회 Vol.2010 No.11

Most automatic transmission use torque converter which is transferring the power with fluid as power transfer device. Because torque converter’s operating fluid is ATF(Automatic Transmission Fluid) and there is slip speed between impeller and turbine, there is the disadvantage that the fuel consumption not good. To overcome this disadvantage, torque converter has lock up clutch which is connecting engine and transmission directly to improve the fuel consumption. However, it is limited to only small area due to the internal combustion engine characteristics. Nowadays, to increase the combustion efficiency and reduce the weight of vehicle, the internal combustion engine is composed of direct injection, variable compression ratio, variable engine displacement, cylinder deactivation, Homogeneous charge compression ignition, turbo charger engine and high pressure fuel injection. Therefore, expansion of direct connection area is indispensable and we need new advanced damper system. Current research presents the optimized damper type and a characteristic through the analysis of influences based on design variables of torque converter, and also provides analytical method of vehicle with commercial software, AMESim. Furthermore, it provides process and design standards to select target characteristics of torsional damper system and introduces the new advanced damper system based on current research.

샌프란시스코강화조약에서 독도문제가 누락된 요인은 무엇인가? -미국의 대일본정책변화와 한국외교실책을 중심으로-

최완 ( Wan Choi ) 동서대학교 일본연구센터 2012 次世代 人文社會硏究 Vol.8 No.-

This paper examines the causes of the worsening of the Dokdo territorial dispute during the San Francisco Peace Treaty negotiations. The reason why the treaty aggravated the Dokdo territorial dispute was that it didn`t make a clear conclusion about who holds the sovereignty over Dokdo. As the US had the biggest influence among the Allied forces, this research will concentrate primarily on the role of the US in the treaty negotiations. As communism was spreading in East Asia, the US reconsidered their political and geographical evaluation of Japan. As a result, the treaty was negotiated to be advantageous for Japan, and Dokdo dispute turned unfavorable for Korea. However, the greatest cause of this unfavorable situation was the diplomatic blunder of the Korean government. During the treaty negotiations, there was an opportunity for Korea to persuade the US about Korean sovereignty over the Dokdo islets. But Korea provided wrong information about Dokdo, and lost their credibility. There were the special circumstances of being in a war; however, we cannot deny that the diplomatic mistakes of Korean government were an important factor in the worsening of the Dokdo territorial dispute.

그래픽 명세로부터 프로그램 생성에 관한 연구

최완(Wan Choi),신연승(Yeon Sung Shin),홍진표(Jin P. Hong) 한국정보과학회 1989 한국정보과학회 학술발표논문집 Vol.16 No.1

본고는 추상화된 그래픽 명세 언어로부터 프로그램을 자동적으로 생산하는 과정에 관하여 설명한다. 컴파일러의 구성과 유사하게 abstract syntax tree를 구축하는 front end부와 이 tree로부터 프로그램을 생산하는 back end로 나누어 기술한다. SDL 종합 개발환경 구축의 일환으로 개발된 SDL로부터 CHILL 변환기는 위의 변환과정을 거쳐서 개발한 도구이다. 이 도구의 개발로 실제 개발 기간의 단축과 CHILL 프로그램의 표준화에 기여할 것으로 사료된다.

CAD/CAM/CAE/PDM 시스템을 이용한 F-125 차량의 개발 (4) - 파워트레인 시스템의 설계 -

최완(Wan Choi),이상헌(Sanghun Lee) 한국자동차공학회 2003 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper describes the development of a powertrain system of a F-125 machine, which is a formula racing car equipped with an l25cc motorcycle engine. First, an engine was selected from existing commercial motorcycle engines based on analysis results of engine performance using BOOST. Then, an air intake system was designed and analyzed using CFD-ACE and BOOST, and then redesigned based on analysis results to maximize the engine powe<br/> performance. All the parts of the powertrain system were modeled as solid objects in CATIA V5. A 3D shape reverse engineering system including a 3D laser scanner and a software was introduced and applied to facilitate solid modeling of purchased parts.