• Journal of the Korea Society of Computer and Information
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• v.11 no.6 s.44
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• pp.151-156
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• 2006

This paper presents an background edge generation based automatic algorithm for detection of moving objects under moving camera. Background image is generated by rotating the fixed the camera on the tripod horizontally, aligning and reorganizing this images. We develop an efficient approach for robust panoramic background edge generation as well as method of edge matching between input image and background image. We applied the proposed algorithm to real image sequences. The proposed method can be successfully realized in various monitoring systems like intrusion detection as well as video surveillance.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.143-148
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• 2003

In recent years, as the optical Communication systems are developed, the demands of essential parts such as splitter, coupler, WDM, and AWG filter are grow rapidly. The fabrication process for them is not, however, automatic. On that reason, the automation is needed for the grow of productivity. The optical alignment and attach ment is the core process in fabrication. In this paper, the 6-axis rotary stage for multi-channel optical alignment system is developed and the dynamic characteristic of this system is studied.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.6
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• pp.64-70
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• 2003

A measurement of spacecraft alignment is an important process of spacecraft assembly, integration and test because it is necessary that a ground station controls the precise positions of on-orbit spacecraft by using the alignment data of attitude orbit control sensors(AOCS) on spacecraft. In addition, accuracy of spacecraft alignment requirement is about $0.1^{\circ}$~$0.7^{\circ}$. The spacecraft alignment is measured by autocollimation of theodolite. This paper describes the measurement principle and method of spacecraft alignment. The result shows that all of the AOCS on the spacecraft are aligned within the tolerance required through the alignment measurement.

• 한국전산유체공학회:학술대회논문집
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• 2006.10a
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• pp.70-73
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• 2006

Mesh generation for the region of interest is prerequisite for numerical analysis of governing partial differential equations describing phenomena with proper physic. Mesh generation is, however, usually considered as a major obstacle for a routine application of numerical approaches in Engineering applications. Therefore automatic mesh generation is highly pursued. In this paper automated quadrilateral surface mesh generation is proposed. According to the present method, Cartesian cells of proper resolution for a region bounding the whole region of interest are first generated and the interior cells are identified. Then projecting their surface meshes onto the boundary surfaces gives surface mesh consisting of quadrilateral cells. This method has been implemented as an application program, and example cases are given.

• 한국전산유체공학회:학술대회논문집
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• 1999.11a
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• pp.108-114
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• 1999

In this paper. a new automatic multi=block grid generation technique for general 2D regions is introduced. According to this simple and robust method, the domain of interest is first triangulated by using Delaunay triangulation of boundary points, and then geometric information of those triangles is used to obtain block topology. Once block boundaries are obtained. structured grid for each block is generated such that grid lines have $C^0-continuity$ across inter-block boundaries. In the final step of the present method, an elliptic grid generation method is applied to smoothen grid distribution for each block and also to re-locale the inter-block boundaries, and eventually to achieve a globally smooth multi-block structured grid system with $C^1-continuity$.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.119-122
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• 2002

Collimators were mostly produced by handwork and semi-automatic system in some companies. Under this situation, automatic manufacturing system for optical collimators is on the rise most essential technique in the development of optical communication components. In this study, automatic manufacturing system was designed and constructed to develop optical collimators with high functionality. Also optical collimators were manufactured using a developed automatic system. We have compared collimators made by automatic system and handwork fer performance test with a measured values of angle alignment, beam size and TIL. As a result, it brought a reduction of the tact time fur manufacturing and improvement of an efficiency of optical collimators, and then it was found that automatic system was indispensable for materialization of optical collimators with high functionality.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.121-121
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• 2004

최근 급속히 성장하고 있는 광통신산업의 발전에 있어서 주목할 만한 경향 중에 하나는 제품의 소형화 및 집적화라 할 것이다. 마이크로 광모듈 접속/조립 시스템은 광모듈을 소형화하고 고기능성 광통신 부품의 개발에 있어 가장 필요한 장비이다. 이에 본 연구에서는 초소형 광모듈 접속/조립 시스템을 개발하기 위하여 두께가 약 30 $\mu\textrm{m}$인 박막형 필터와 렌즈일체형 파이버를 접속/조립할 수 있는 시스템을 개발 및 초소형 광통신용 1$\times$1 OADM(Optical Add/Drop Module) 모듈을 제작하였다.(중략)

• Journal of the Semiconductor & Display Technology
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• v.6 no.1 s.18
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• pp.43-48
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• 2007

For exposure systems, very accurate alignment between the mask and the substrate is indispensable. In this paper, an automatic alignment system using machine vision for exposure systems is described. Machine vision algorithms are described in detail including extraction of an alignment mark's center position and camera calibration. Methods for extracting parameters for alignment are also presented with some compensation techniques to reduce alignment time. Our alignment system was implemented with a vision system and motion control stages. The performance of the alignment system has been extensively tested with satisfactory results. The performance evaluation shows alignment accuracy of lum within total alignment time of about $2{\sim}3$ seconds including stage moving time.

• Review of KIISC
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• v.18 no.5
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• pp.62-72
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• 2008

인터넷 뱅킹은 인터넷을 통해 금융 업무를 처리하는 시스템으로, 시 공간적 제약이 없어 이용자가 크게 증가하고 있지만 인터넷을 기반으로 한 웹 공격으로 인하여 많은 위협을 받고 있다. 인터넷 뱅킹은 서비스를 제공하는 은행에 따라 사용자 인터페이스와 처리 방법이 매우 다양하므로, 인터넷 뱅킹 시스템을 목표로 한 웹 공격을 탐지하기 위해서는 해당 인터넷 뱅킹 서비스의 특징을 반영할 수 있는 고유의 패턴을 생성해야 한다. 본 논문에서는 서열 정렬 알고리즘을 이용하여 인터넷 뱅킹 이용에 대한 정상 및 비정상 패턴을 자동으로 생성하여 웹 공격을 탐지하고 분석하는 방법을 제안한다. 제시한 방법의 성능 평가를 위하여, 모의 인터넷 뱅킹 프로그램을 설치한 후 정상적인 이용과 웹 공격을 시도한 자료를 구분하여 수집하고 유사도를 측정하였다. 실험결과 제안된 기법이 오탐율이 낮고 탐지 성능 또한 뛰어남을 확인하였다. 그리고 전문가의 도움 없이 정상 패턴과 비정상 패턴을 생성할 수 있어 효율적으로 변형된 공격이나 새로운 공격을 차단하고 비정상 행위에 판단에 대한 근거를 제시할 수 있음을 보였다.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.150-155
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• 2005

In recent years, as the demands of VBNS(Very high speed Backbone Network Service) and VDSL(Very high-data rate Digital Subscriber Line) increase, the development of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, WDM elements increase. The alignment and the attachment technology are very important to fabricate the optical elements for communication. In this paper, the mechanism of rotational stage are studied. with the three different method and the results of them are applied to the design of the system. The performance test of resolution and travel is performed.