• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.583-598
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• 2022

As human-based tunnel inspections are affected by the subjective judgment of the inspector, making continuous history management difficult. There is a lot of deep learning-based automatic crack detection research recently. However, the large public crack datasets used in most studies differ significantly from those in tunnels. Also, additional work is required to build sophisticated crack labels in current tunnel evaluation. Therefore, we present a method to improve crack detection performance by inputting existing datasets into a deep learning model. We evaluate and compare the performance of deep learning models trained by combining existing tunnel datasets, high-quality tunnel datasets, and public crack datasets. As a result, DeepLabv3+ with Cross-Entropy loss function performed best when trained on both public datasets, patchwise classification, and oversampled tunnel datasets. In the future, we expect to contribute to establishing a plan to efficiently utilize the tunnel image acquisition system's data for deep learning model learning.

• Progress in Medical Physics
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• v.22 no.1
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• pp.42-51
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• 2011

Nuclear medicine images (SPECT, PET) were widely used tool for assessment of myocardial viability and perfusion. However it had difficult to define accurate myocardial infarct region. The purpose of this study was to investigate methodological approach for automatic measurement of rat myocardial infarct size using polar map with adaptive threshold. Rat myocardial infarction model was induced by ligation of the left circumflex artery. PET images were obtained after intravenous injection of 37 MBq $^{18}F$-FDG. After 60 min uptake, each animal was scanned for 20 min with ECG gating. PET data were reconstructed using ordered subset expectation maximization (OSEM) 2D. To automatically make the myocardial contour and generate polar map, we used QGS software (Cedars-Sinai Medical Center). The reference infarct size was defined by infarction area percentage of the total left myocardium using TTC staining. We used three threshold methods (predefined threshold, Otsu and Multi Gaussian mixture model; MGMM). Predefined threshold method was commonly used in other studies. We applied threshold value form 10% to 90% in step of 10%. Otsu algorithm calculated threshold with the maximum between class variance. MGMM method estimated the distribution of image intensity using multiple Gaussian mixture models (MGMM2, ${\cdots}$ MGMM5) and calculated adaptive threshold. The infarct size in polar map was calculated as the percentage of lower threshold area in polar map from the total polar map area. The measured infarct size using different threshold methods was evaluated by comparison with reference infarct size. The mean difference between with polar map defect size by predefined thresholds (20%, 30%, and 40%) and reference infarct size were $7.04{\pm}3.44%$, $3.87{\pm}2.09%$ and $2.15{\pm}2.07%$, respectively. Otsu verse reference infarct size was $3.56{\pm}4.16%$. MGMM methods verse reference infarct size was $2.29{\pm}1.94%$. The predefined threshold (30%) showed the smallest mean difference with reference infarct size. However, MGMM was more accurate than predefined threshold in under 10% reference infarct size case (MGMM: 0.006%, predefined threshold: 0.59%). In this study, we was to evaluate myocardial infarct size in polar map using multiple Gaussian mixture model. MGMM method was provide adaptive threshold in each subject and will be a useful for automatic measurement of infarct size.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2002.05a
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• pp.315-322
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• 2002

최근에 경험적 지식을 체계화하는 방법으로 사례기반추론(CBR: Case Based Reasoning) 및 규칙기반추론(RBR: Rule Based Reasoning)이 여러 분야에서 이용되고 있다. CBR과 RBR이 각각 활용되기도 하지만 문제 해결의 정확성을 높이기 위해 복합된 형태로 사용되기도 하고, 흑은 효과적으로 문제를 해결하기 위해 문제 해결 단계별로 각각 사용되기도 한다 또한 데이터에서 지식을 추출하기 위한 세부 알고리즘으로는 인공지능과 통계적 분석기법 등이 활발하게 연구 및 적용되고 있다. 본 연구는 모니터의 핵심 부품인 섀도우마스크(Shadow Mask)를 개발하는데 있어 도면 협의부터 설계가지의 과정에 CBR과 RBR을 활용하고 발생되는 데이터를 이용하여 진화(Evolution)하는 지식기반시스템(Knowledge Based System)으로 구축하는 것을 목적으로 하고 있다. 특히 도면 협의시 인터넷상에 웹서버 시스템을 통하여 규격 (User Spec.)을 생성하고 이를 이용하여 자동으로 도면이 설계되도록 하고 저장된 사례들을 공유할 수 있도록 하여 도면 검토 시간이 단축되고 검토의 정확성을 기할 수 있어 실패비용을 감소시켰다. 그리고 실제 설계시 CBR과 RBR을 활용하여 자동설계를 할 수 있게 하였고 현장에서 발생되는 데이터를 지식화하여 유사사례 설계가 가능하도록 하였다. 지식기반시스템은 신속한 도면 검토가 가능하므로 인원 활용이 극대화되고, 섀도우 마스크 설계자와 마스터 패턴 설계자 사이의 원활한 의사소통을 통해 고객과의 신뢰성 확보와 신인도 향상을 기대할 수 있는 효과가 있다. 그리고 고급설계자에게만 의지되어온 것을 어느 정도 해결할 수 있고, 신입설계자에게는 훌륭한 교육시스템이 될 수 있다.한 도구임을 입증하였다는 점에서 큰 의의를 갖는다고 하겠다.운 선용품 판매 및 관련 정보 제공 등 해운 거래를 위한 종합적인 서비스가 제공되어야 한다. 이를 위해, 본문에서는 e-Marketplace의 효율적인 연계 방안에 대해 해운 관련 업종별로 제시하고 있다. 리스트 제공형, 중개형, 협력형, 보완형, 정보 연계형 등이 있는데, 이는 해운 분야에서 사이버 해운 거래가 가지는 문제점들을 보완하고 업종간 협업체제를 이루어 원활한 거래를 유도할 것이다. 그리하여 우리나라가 동북아 지역뿐만 아니라 세계적인 해운 국가 및 물류 ·정보 중심지로 성장할 수 있는 여건을 구축하는데 기여할 것이다. 나타내었다.약 1주일간의 포르말린 고정이 끝난 소장 및 대장을 부위별, 별 종양개수 및 분포를 자동영상분석기(Kontron Co. Ltd., Germany)로 분석하였다. 체의 변화, 장기무게, 사료소비량 및 마리당 종양의 개수에 대한 통계학적 유의성 검증을 위하여 Duncan's t-test로 통계처리 하였고, 종양 발생빈도에 대하여는 Likelihood ration Chi-square test로 유의성을 검증하였다. C57BL/6J-Apc$^{min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투여한 대조군의 대장선종의 발생률은 84%(Group 3; 21/25례)로써 I3C 100ppm 및 300ppm을 투여한 경우에 있어서는 각군 모두 60%(Group 1; 12/20 례, Group 2; 15/25 례)로 감소하는 경향을 나타내었다. 대장선종의 마리당 발생개수에 있어서는 C57BL/6J-Apc$^{min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투여한

• The Transactions of the Korea Information Processing Society
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• v.7 no.9
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• pp.3037-3047
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• 2000

This paper describes a method of tracking a close leading vehicle by color image processing using the pairs of tail and brake lights. which emit red light and are housed on the rear of the vehicle in stop-and-go traffic condition. In the color image converted as an HSV color model. candidate regions of rear lights are identified using the color features of a pair of lights. Then. the pair of tailor brake lights are detected by means of the geometrical features and location features for the pattern of the tail and brake lights. The location of the leading vehicle can be estimated by the location of the detected lights and the vehicle can be tracked continuously. It is also possible to detect the braking status of the leading vehicle by measuring the change in HSV color components of the pair of lights detected. In the experiment. this method tracked a leading vehicle successfully from urban road images and was more useful at night than in the daylight. The KAV-Ill (Korea Autonomous Vehicle- Ill) equipped with a color vision system implementing this algorithm was able to follow a leading vehicle autonomously at speeds of up to 15km!h on a paved road at night. This method might be useful for developing an LSA (Low Speed Automation) system that can relieve driver's stress in the stop-and-go traffic conditions encountered on urban roads.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.12A
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• pp.2109-2119
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• 2001

In this paper, a fast information extraction algorithm for object-based MPEG-4 application from MPEG-2 bit-steam is proposed. For object-based MPEG-4 conversion, we need to extract such information as object-image, shape-image, macro-block motion vector, and header information from MPEG-2 bit-stream. If we use the extracted information, fast conversion for object-based MPEG-4 is possible. The proposed object extraction algorithm has two important steps, namely the motion vectors extraction from MPEG-2 bit-stream and the watershed algorithm. The algorithm extracts objects using user\`s assistance in the intra frame and tracks then in the following inter frames. If we have an unsatisfactory result for a fast moving object, the user can intervene to correct the segmentation. The proposed algorithm consist of two steps, which are intra frame object extracts processing and inter frame tracking processing. Object extracting process is the step in which user extracts a semantic object directly by using the block classification and watersheds. Object tacking process is the step of the following the object in the subsequent frames. It is based on the boundary fitting method using motion vector, object-mask, and modified watersheds. Experimental results show that the proposed method can achieve a fast conversion from the MPEG-2 bit-stream to the object-based MPEG-4 input.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.3
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• pp.91-102
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• 2004

In this paper, a fast information extraction algorithm for object-based MPEG-4 application from MPEG-1,2 is proposed. For object-based MPEG-4 conversion, we need to extract such information as object-image, shape-image, macro-block motion vector, and header information from MPEG-1,2 bit-stream. If we use the extracted information, fast conversion for object-based MPEG-4 is possible. The proposed object extraction algerian has two important steps, namely the motion vector extraction from MPEG-1,2 bit-stream and the watershed algerian The algorithm extracts objects using user's assistance in the intra frame and tracks then in the following inter frames. If we have an unsatisfactory result for a fast moving object the user can intervene to connect the segmentation. The proposed algorithm consist of two steps, which are intra frame object extracting processing and inter frame tracking processing. Object extracting process is the step in which user extracts a semantic object directly by using the block classification and watersheds. Object tracking process is the step of the following the object in the subsequent frames. It is based on the boundary fitting method using motion vector, object-mask and modified watersheds. Experimental results show that the proposed method can achieve a fast conversion from the MPEG-1,2 bit-stream to the object-based MPEG-4 input.

• The KIPS Transactions:PartB
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• v.19B no.2
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• pp.123-126
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• 2012

This paper proposed a method to separate a liver into left and right liver lobes for simple and exact volumetry of the river graft at abdominal MDCT(Multi-Detector Computed Tomography) image before the living donor liver transplantation. A medical team can evaluate an accurate river graft with minimized interaction between the team and a system using this algorithm for ensuring donor's and recipient's safe. On the image of segmented liver, 2 points(PMHV: a point in Middle Hepatic Vein and PPV: a point at the beginning of right branch of Portal Vein) are selected to separate a liver into left and right liver lobes. Middle hepatic vein is automatically segmented using PMHV, and the cutting line is decided on the basis of segmented Middle Hepatic Vein. A liver is separated on connecting the cutting line and PPV. The volume and ratio of the river graft are estimated. The volume estimated using 2 points are compared with a manual volume that diagnostic radiologist processed and estimated and the weight measured during surgery to support proof of exact volume. The mean ${\pm}$ standard deviation of the differences between the actual weights and the estimated volumes was $162.38cm^3{\pm}124.39$ in the case of manual segmentation and $107.69cm^3{\pm}97.24$ in the case of 2 points method. The correlation coefficient between the actual weight and the manually estimated volume is 0.79, and the correlation coefficient between the actual weight and the volume estimated using 2 points is 0.87. After selection the 2 points, the time involved in separation a liver into left and right river lobe and volumetry of them is measured for confirmation that the algorithm can be used on real time during surgery. The mean ${\pm}$ standard deviation of the process time is $57.28sec{\pm}32.81$ per 1 data set ($149.17pages{\pm}55.92$).

• 한국HCI학회:학술대회논문집
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• 2006.02b
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• pp.362-369
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• 2006

3 차원 그래픽스에 적용하는 한국어 립씽크 합성 체계를 연구하여, 말소리에 대응하는 자연스러운 립씽크를 자동적으로 생성하도록 하는 디자인 시스템을 연구 개발하였다. 페이셜애니메이션은 크게 나누어 감정 표현, 즉 표정의 애니메이션과 대화 시 입술 모양의 변화를 중심으로 하는 대화 애니메이션 부분으로 구분할 수 있다. 표정 애니메이션의 경우 약간의 문화적 차이를 제외한다면 거의 세계 공통의 보편적인 요소들로 이루어지는 반면 대화 애니메이션의 경우는 언어에 따른 차이를 고려해야 한다. 이와 같은 문제로 인해 영어권 및 일본어 권에서 제안되는 음성에 따른 립싱크 합성방법을 한국어에 그대로 적용하면 청각 정보와 시각 정보의 부조화로 인해 지각의 왜곡을 일으킬 수 있다. 본 연구에서는 이와 같은 문제점을 해결하기 위해 표기된 텍스트를 한국어 발음열로 변환, HMM 알고리듬을 이용한 입력 음성의 시분할, 한국어 음소에 따른 얼굴특징점의 3 차원 움직임을 정의하는 과정을 거쳐 텍스트와 음성를 통해 3 차원 대화 애니메이션을 생성하는 한국어 립싱크합성 시스템을 개발 실제 캐릭터 디자인과정에 적용하도록 하였다. 또한 본 연구는 즉시 적용이 가능한 3 차원 캐릭터 애니메이션뿐만 아니라 아바타를 활용한 동적 인터페이스의 요소기술로서 사용될 수 있는 선행연구이기도 하다. 즉 3 차원 그래픽스 기술을 활용하는 영상디자인 분야와 HCI 에 적용할 수 있는 양면적 특성을 지니고 있다. 휴먼 커뮤니케이션은 언어적 대화 커뮤니케이션과 시각적 표정 커뮤니케이션으로 이루어진다. 즉 페이셜애니메이션의 적용은 보다 인간적인 휴먼 커뮤니케이션의 양상을 지니고 있다. 결국 인간적인 상호작용성이 강조되고, 보다 편한 인간적 대화 방식의 휴먼 인터페이스로 그 미래적 양상이 변화할 것으로 예측되는 아바타를 활용한 인터페이스 디자인과 가상현실 분야에 보다 폭넓게 활용될 수 있다.

• Journal of the Korea Computer Graphics Society
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• v.15 no.4
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• pp.31-40
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• 2009

Captured motion data is widely used today in a variety of areas including film production, game development, sports analysis, and medical rehabilitation. The ability of analyzing and processing motion data has increased rapidly for last decades. However, it is still difficult for users to quickly understand the contents of motion data consisting of a series of time-varying poses. One typical approach is to visualize consecutive poses in sequence while adjusting three-dimensional view, which is often time-consuming and laborious especially when users need to repeatedly control time and view in order to search for desired motions. We present a method of visualizing motion data as a sequence of images in comic book layout so that users can rapidly understand the overall flows of motion data, and easily identify their desired motions. The usefulness of our approach is demonstrated by visualizing various kinds of motion data including locomotion, boxing, and interaction with environments.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.825-834
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• 2023

The demands of people who purchase fashion products on Internet shopping are gradually increasing, and attempts are being made to provide user-friendly images with 3D contents and web 3D software instead of pictures and videos of products provided. As a reason for this issue, which has emerged as the most important aspect in the fashion web shopping industry, complaints that the product is different when the product is received and the image at the time of purchase has been heightened. As a way to solve this problem, various image processing technologies have been introduced, but there is a limit to the quality of 2D images. In this study, we proposed an automatic conversion technology that converts 2D images into 3D and grafts them to web 3D technology that allows customers to identify products in various locations and reduces the cost and calculation time required for conversion. We developed a system that shoots a mannequin by placing it on a rotating turntable using only 8 cameras. In order to extract only the clothing part from the image taken by this system, markers are removed using U-net, and an algorithm that extracts only the clothing area by identifying the color feature information of the background area and mannequin area is proposed. Using this algorithm, the time taken to extract only the clothes area after taking an image is 2.25 seconds per image, and it takes a total of 144 seconds (2 minutes and 4 seconds) when taking 64 images of one piece of clothing. It can extract 3D objects with very good performance compared to the system.