• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.283-284
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• 2009

본 논문은 단일 카메라 환경에서 손 형상을 입력정보로 사용하여 손 영역만을 분할한 후 자기 조직화 특징 지도(SOFM: Self Organized Feature Map) 신경망 알고리즘을 이용하여 손 형상을 인식함으로서 수화인식을 위한 보다 안정적이며 강인한 인식 시스템을 구현하고자 한다.

• Journal of the Korea Computer Graphics Society
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• v.24 no.4
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• pp.29-38
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• 2018

In this paper, we propose an automatic segmentation method of meniscus in knee MR images by automatic meniscus localization, multi-atlas-based locally-weighted voting, and patch-based edge feature classification. First, after segmenting the bone and knee articular cartilage, the volume of interest of the meniscus is automatically localized. Second, the meniscus is segmented by multi-atlas-based locally-weighted voting taking into account the weights of shape and intensity distribution in the volume of interest of the meniscus. Finally, to remove leakage to the collateral ligaments with similar intensity, meniscus is refined using patch-based edge feature classification considering shape and distance weights. Dice similarity coefficient between proposed method and manual segmentation were 80.13% of medial meniscus and 80.81 % for lateral meniscus, and showed better results of 7.25% for medial meniscus and 1.31% for lateral meniscus compared to the multi-atlas-based locally-weighted voting.

• Journal of Integrative Natural Science
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• v.3 no.1
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• pp.38-42
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• 2010

인간은 정보전달을 위하여 언어 이외에 동작, 표정과 같은 비언어적인 수단을 이용한다. 이러한 비언어적인 수단을 정확히 분석 할 수 있다면 인간과 컴퓨터간의 자연스럽고 지적인 인터페이스를 구축할 수 있게 된다. 본 논문은 별도의 센서를 부착하지 않은 단일 카메라 환경에서 손 형상을 입력정보로 사용하여 손 영역만을 분할한 후 자기 조직화 특징 지도(SOFM: Self Organized Feature Map) 신경망 알고리즘을 이용하여 손 형상을 인식함으로서 수화인식을 위한 보다 안정적이며 강인한 인식 시스템을 구현하고자 한다. 제안 방법으로는 피부색 정보를 이용하여 배경으로부터 손 영역만을 추출한 후 추출된 손 영역의 형상을 인식한다(전처리과정으로 모델이미지의 사이즈와 압축 및 컬러에 대한 정보를 정규화 시켰다). 또한 인식 효율을 높이기 위해 SOFM 신경망 알고리즘을 적용함으로서 보다 안정적으로 손 형상을 인식할 수 있게 되었으며, 손 형상 인식률에 대한 안전성과 정확성을 향상시킬 수 있었다. 그리고 인식된 손 형상의 의미를 텍스트로 보여줌으로서 사용자의 의사를 정확하게 전달할 수 있다.

• KIPS Transactions on Software and Data Engineering
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• v.1 no.3
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• pp.187-194
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• 2012

Prostate cancer is one of the most frequent cancers in men and is a major cause of mortality in the most of countries. In many diagnostic and treatment procedures for prostate disease, transrectal ultrasound(TRUS) images are being used because the cost is low. But, accurate detection of prostate boundaries is a challenging and difficult task due to weak prostate boundaries, speckle noises and the short range of gray levels. This paper proposes a method for automatic prostate segmentation in TRUS images using its average shape model and invariant features. This approach consists of 4 steps. First, it detects the probe position and the two straight lines connected to the probe using edge distribution. Next, it acquires 3 prostate patches which are in the middle of average model. The patches will be used to compare the features of prostate and nonprostate. Next, it compares and classifies which blocks are similar to 3 representative patches. Last, the boundaries from prior classification and the rough boundaries from first step are used to determine the segmentation. A number of experiments are conducted to validate this method and results showed that this new approach extracted the prostate boundary with less than 7.78% relative to boundary provided manually by experts.

• Proceedings of the Korea Multimedia Society Conference
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• 2004.05a
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• pp.688-691
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• 2004

본 논문에서는 메쉬, 복셀, 골격 데이터를 포함하는 복합적인 옥트리 기반의 형상 표현을 이용하여 해마의 형상을 분석하기 위한 효과적인 방법을 제공한다. 먼저, 자기공명영상으로부터 분할된 해마 영역에 마칭큐브 알고리즘을 적용하여 다단계 메쉬 데이터를 생성한다. 이렇게 생성된 메쉬 모델을 하드웨어 깊이맵을 이용한 복셀화 과정을 통하여, 중간 단계의 이진 복셀 표현으로 변환한다. 마지막으로 광선 추적 방법에 의해 추출된 샘플 메쉬들에 대하여 L2 Norm을 계산함으로써 형상 특징을 생성한다. 본 연구에서 제시한 방법은 사용자 피킹 인터페이스를 이용하여 국부적 부위에서의 계층적 형상 분석을 가능하게 한다. 또한 계층적 Level-of-Detail 접근방법은 정확도를 유지하며 형상분석의 소요 시간을 절약하도록 한다.

• Korean Journal of Computational Design and Engineering
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• v.9 no.1
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• pp.44-50
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• 2004

Mechanical parts are often grouped into part families based on the similarity of their shapes, to support efficient manufacturing process planning and design modification. The 2-part sequence papers present similarity assessment techniques to support part family classification for machined parts. These exploit the multiple feature decompositions obtained by the feature recognition method using convex decomposition. Convex decomposition provides a hierarchical volumetric representation of a part, organized in an outside-in hierarchy. It provides local accessibility directions, which supports abstract and qualitative similarity assessment. It is converted to a Form Feature Decomposition (FFD), which represents a part using form features intrinsic to the shape of the part. This supports abstract and qualitative similarity assessment using positive feature volumes. FFD is converted to Negative Feature Decomposition (NFD), which represents a part as a base component and negative machining features. This supports a detailed, quantitative similarity assessment technique that measures the similarity between machined parts and associated machining processes implied by two parts' NFDs. Features of the NFD are organized into branch groups to capture the NFD hierarchy and feature interrelations. Branch groups of two parts' NFDs are matched to obtain pairs, and then features within each pair of branch groups are compared, exploiting feature type, size, machining direction, and other information relevant to machining processes. This paper, the first one of the two companion papers, describes the similarity assessment methods using convex decomposition and FFD.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.28-36
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• 2013

This study proposed a robust detection algorithm. It detects hands more stably with respect to changes in light and rotation for the identification of a hand shape. Also it satisfies both efficiency of calculation and the function of detection. The algorithm proposed segmented the hand area through pre-processing using a hand shape as input information in an environment with a single camera and then identified the shape using a Self Organized Feature Map(SOFM). However, as it is not easy to exactly recognize a hand area which is sensitive to light, it has a large degree of freedom, and there is a large error bound, to enhance the identification rate, rotation information on the hand shape was made into a database and then a principal component analysis was conducted. Also, as there were fewer calculations due to the fewer dimensions, the time for real-time identification could be decreased.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.569-574
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• 2002

As consumer's desire becomes various, agility of mold manufacturing is most important factor for competence of manufacturer. In common works to use commercial CAM system to generate tool path, some decision making process is required to produce optimal result of CAM systems, The paper proposes a methodology for computer-assisted tool selection procedures for various cutting type, such as rough, semi-rough and finish cuts. The system provides assist-tool-items for machining of design model part of injection meld die by analyzing sliced CAD model of die cavity and core. Also, the generating NC-code of the tool size is used to calculate machining time. The system is developed with commercial CAM using API. This module will be used for optimization of tool selection and planning process.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2006.11a
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• pp.21-26
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• 2006

본 논문은 가상 착의 시스템에 관한 것으로, 2D의류 모델 영상에서 의류 형상을 분할한 후, 분할된 의류 형상 영역의 음영 및 조명 특성을 유지하면서 사용자가 선택한 새로운 직물 패턴을 가상적으로 착용시킬 수 있는 2D 실사 기반 가상 착의 시스템의 직물 텍스쳐 매핑에 관한 것이다. 제안된 방법은 다양한 디지털 환경에서 실시간 처리가 가능하고 자연스럽고 사실적인 착용감을 제공할 뿐만 아니라 사용자의 수작업을 최대한 제거한 반자동화 처리가 가능하기 때문에 높은 실용성과 편리한 사용자 인터페이스를 제공할 수 있는 것이 특징이다. 제안된 방법에 따르면 실제 의복을 제작하지 않은 상태에서도 직물 원단의 디자인이 의복의 외관에 미치는 영향을 시뮬레이션할 수 있음에 따라 직물 디자이너의 창작활동을 도와줄 수 있고, 온라인상에서 직물 원단이나 의류를 거래할 시에 구매자의 의사결정을 지원해 B2B 또는 B2C 전자상거래 행위를 촉진할 수 있다. 더불어 기성복이나 맞춤복 모두에 대해 소비자가 자신의 취향에 어울리는 직물 패턴을 용이하게 선택하고 디자인하여 주문제작을 수행하는 거래환경을 조성할 수 있다.

• Korean Journal of Computational Design and Engineering
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• v.12 no.4
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• pp.245-254
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• 2007

This research proposed feature extraction algorithms as an input of STEP Ap214 data, and feature parameterization process to simplify further design change and maintenance. The procedure starts with suppression of blend faces of an input solid model to generate its simplified model, where both constant and variable-radius blends are considered. Most existing cell decomposition algorithms utilize concave edges, and they usually require complex procedures and computing time in recomposing the cells. The proposed algorithm using reference features, however, was found to be more efficient through testing with a few sample cases. In addition, the algorithm is able to recognize depression features, which is another strong point compared to the existing cell decomposition approaches. The proposed algorithm was implemented on a commercial CAD system and tested with selected industrial product models, along with parameterization of recognized features for further design change.