• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.550-555
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• 1993

The aim of this paper is to present the development of visual seam tracking system equipped with visual range finder. The visual range finder, which consists of a CCD camera and a diode laser system with line generating optics, developed to recognize the types of weld joints and detect the location of weld joints. In practical applications, however, images of the weld joints are often degraded due to spatters, are flares, surface specularity, and welding smoke. To overcome the problem, this paper proposes a syntactic approach which is a class of artificial intelligence techniques. In the approach, the type of weld joint is inferred based upon the production rules which are linguiques grammars consisting of a set of line and junction primitives of laser strip image projected on weld joint. The production rules eliminate several noisy primitives to create new primitives through the merging process of primitives. After the recognition of weld joint, arc welding is started and the location of weld joints is repeatedly detected using a spring model-based template matching in which the template model is a by-product of the recognition process of weld joint. To show the effectiveness of the proposed approach a series of experiments-identification and robotic tracking-are conducted for four different types of weld joints.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.1
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• pp.80-88
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• 2001

The existed approaches to analyzing real-time schedulability take place exponential time and space complexity of this methods, since these uses a fixed priority scheduling and/or traverse all possible state spaces. This paper judges whether it is satisfied a given deadlines for real-time processes regarding a minimum execution time of process, periodic, deadline and a synchronizion time of processes by using the transaction rules of process algebra, and proposes a retrieval algorithm for unschedulable processes based on GUI environment. And we implement and evaluate the scheduling state analyzer that displays visually the result of schedulabiliy analysis for real-time processes.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.463-466
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• 2009

Some strategies for the integrated water management system based on GIS was suggested for the comprehensive and systematic management on the watershed. Contents of database and thematic layers for the related elements with GIS was indicated to estimate the quantity of total pollution loads and to simulate the water quality. Also, functions for the information providing was suggested on the connection with spatial data and attribute data, the search for collected data, the analysis for time series, and the visual presentations. Finally, it was suggested to integrate the existing systems and database structures, and to construct of data warehouse.

• Journal of Welding and Joining
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• v.18 no.3
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• pp.60-67
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• 2000

In this study, we constructed a preview-sensing visual sensor system for weld seam tracking in GMA welding. The visual sensor consists of a CCD camera, a diode laser system with a cylindrical lens and a band-pass-filter to overcome the degrading of image due to spatters and/or arc light. To obtain weld joint position and edge points accurately from the captured image, we compared Hough transform method with central difference method. As a result, we present Hough transform method can more accurately extract the points and it can be applied to real time weld seam tracking. Image processing is carried out to extract straight lines that express laser stripe. After extracting the lines, weld joint position and edge points is determined by intersecting points of the lines. Although a spatter trace is in the image, it is possible to recognize the position of weld joint. Weld seam tracking was precisely implemented with adopting Hough transform method, and it is possible to track the weld seam in the case of offset angle is in the region of $\pm15^{\circ}$.

• The KIPS Transactions:PartD
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• v.11D no.4
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• pp.799-808
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• 2004

Well documented, simplified and clarified source code is required for the mission critical application software area in which C programing language is generally used. We suggest an XML_based comment management system for C source code. The comment management system is composed of 6 modules including comment user module, reviewer module, comment extraction module, comment traceability link module, comment tag definition module and storage management module. The XML comment tags defined in this paper cover categories of the development process activities applying the IEEE standard 1028 and IEEE standard 1012. The XML Schema Is used to insert comments into C source code and to extract XML tags from C source code and the XSL-FO is used fur the visual display professing o( comment extraction results.

• Journal of the Korea Computer Graphics Society
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• v.10 no.2
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• pp.1-9
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• 2004

본 논문에서는 바이러스와 같은 생화학 물질의 분자구조를 3 차원 모델로 시각화하여 관찰하고, 그 분자모델을 직관적인 방법으로 조작하기 위한 가상 현실 분자 모델링 시스템을 제안한다. 이 시스템을 사용하면, 입체영상 디스플레이 장치와 데이터 글러브 및 동작 추적 장치를 사용하여 3 차원 분자 모델을 실감나게 조작할 수 있어서 효율적으로 분자들을 관찰하고 결합, 분리하는 등의 분자 모델링 작업이 가능하다. 사용자들은 마우스나 키보드 등의 장비 대신에 자연스러운 몸 동작이나 손 동작을 이용하여 분자 모델링 작업을 위한 동작을 하게 된다. 분자들의 결합을 화학적으로 정확하게, 그리고 실시간으로 시뮬레이션 하기 위해서 에너지 계산 알고리즘을 구현하였으며 이러한 작업이 가능하도록 분자 구조를 표현하는 새로운 자료구조를 제안하였다. 본 연구에서 제안하는 동작 기반의 VR 분자 모델링 시스템의 타당성을 검증하기 위하여 HIV 바이러스 분자를 가지고 분자 모델링 작업을 수행하였고, 사용자 테스트를 실시하여 기존의 방식과 작업 성능 및 사용자 만족도를 비교하였다.

• Journal of the Korea Society of Computer and Information
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• v.9 no.4 s.32
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• pp.85-91
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• 2004

The use of gestures provides an attractive alternate to cumbersome interface devices for human-computer interaction. This has motivated a very active research area concerned with computer vision-based analysis and interpretation of hand gestures The most important issues in gesture recognition are the simplification of algorithm and the reduction of processing time. The mathematical morphology based on geometrical set theory is best used to perform the processing. The key idea of proposed algorithm is to track a trajectory of center points in primitive elements extracted by morphological shape decomposition. The trajectory of morphological center points includes the information on shape orientation. Based on this characteristic we proposed the morphological gesture sequence recognition algorithm using feature vectors calculated to the trajectory of morphological center points. Through the experiment, we demonstrated the efficiency of proposed algorithm.

• Annals of Clinical Neurophysiology
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• v.8 no.1
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• pp.44-47
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• 2006

Background: The present study used magnetoencephalography (MEG) to investigate the neural substrates for modified version of Treisman's visual search task. Methods: Two volunteers who gave informed consent participated MEG experiment. One was 27- year old male and another was 24-year-old female. All were right handed. Experiment were performed using a 306-channel biomagnetometer (Neuromag LTD). There were three task conditions in this experiment. The first was searching an open circle among seven closed circles (open condition). The second was searching a closed circle among seven uni-directionally open circles (closed condition). And the third was searching a closed circle among seven eight-directionally open circles (random (closed) condition). In one run, participants performed one task condition so there were three runs in one session of experiment. During one session, 128 trials were performed during every three runs. One participant underwent one session of experiment. The participant pressed button when they found targets. Magnetic source localization images were generated using software programs that allowed for interactive identification of a common set of fiduciary points in the MRI and MEG coordinate frames. Results: In each participant we can found activations of anterior cingulate, primary visual and association cortices, posterior parietal cortex and brain areas in the vicinity of thalamus. Conclusions: we could find activations corresponding to anterior and posterior visual attention systems.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.4
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• pp.411-420
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• 1999

Coastal development and reclamation work make environment of shore destroy, such as rapid change of land use and destruction of wet-land and ocean ecosystem. Therefore new technique to detect change have been needed. This study designed new change detection method and applied to study area. The change detection image and quantitative change area by each classes are calculated. Also, this study can use the basic idea-determination data for coastal development and city plan as the sense of sight by changed images that changed from any land-cover to any land-cover between two dates.

• Bulletin of the Korean Space Science Society
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• 2009.10a
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• pp.42.2-42.2
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• 2009

한국천문연구원에서 개발 중인 KHz급 Satellite Laser Ranging(SLR) 시스템인 ARGO-M 의 운영시스템 중의 하나인 Interface Control System 은 현재 시각에서의 위성의 위치를 개산하여 추적마운트부에 Tracking 정보를 제공하고, 주기적으로 발사되는 레이저의 귀환 시간을 계산하여 수신광검출기 게이트를 열어야 하는 시간을 FPGA 보드에 전달하는 기능 등을 수행하게 된다. 이러한 일련의 작업은 각각 필요한 시점에 정확하게 실행되어야 하며 이를 위해 실시간 운영체계가 사용될 예정이다. 실시간 운영체계 하에서 Ranging 에 관련한 프로세스를 수행할 경우에 발생될 수 있는 문제점을 검토하기 위해서 기존에 Austria Graz SLR 관측소에서 사용하고 있는 DOS용 테스트 프로그램을 실시간 운영체계로 검토되고 있는 INtime 환경으로 이식하여 성능을 기존의 DOS 프로그램과 비교하여 보았다. Controller 역할을 담당하고 있는 FPGA 보드와의 데이터 통신의 주기성을 확인하는 시험 결과 실시간 운영체계를 사용하는 경우가 USB 사용 등 외적인 교란에 의한 영향을 적게 받는 것을 확인 할 수 있었다. 또한 500피코초 단위의 해상도를 갖는 내부 이벤트 타이머와의 연계, 레이저 발사 명령, 광검출기의 게이트 여닫기 등의 프로세스가 실시간 환경에서 문제점 없이 구현 가능함을 확인하였다.