• 한국콘텐츠학회논문지
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• 제9권7호
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• pp.159-170
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• 2009

온라인 기반의 3차원 얼굴 애니메이션을 위해서 실시간으로 얼굴을 캡처하고 표정 데이터를 추출하는 것은 매우 중요한 작업이다. 최근 동영상 입력을 통해 연기자의 표정을 캡처하고 그것을 그대로 3차원 얼굴 모델에 표현하는 비전 기반(vision-based) 방법들에 대한 연구가 활발히 이루어지고 있다. 본 논문 에서는 실시간으로 입력되는 동영상으로부터 얼굴과 얼굴 특징점들을 자동으로 검출하고 이를 추적하는 시스템을 제안한다. 제안 시스템은 얼굴 검출과 얼굴 특징점 추출 및 추적과정으로 구성된다. 얼굴 검출은 3차원 YCbCr 피부 색상 모델을 이용하여 피부 영역을 분리하고 Harr 기반 검출기를 이용해 얼굴 여부를 판단한다. 얼굴 표정에 영향을 주는 눈과 입 영역의 검출은 밝기 정보와 특정 영역의 고유한 색상 정보를 이용한다. 검출된 눈과 입 영역에서 MPEG-4에서 정의한 FAP를 기준으로 10개의 특징점을 추출하고, 컬러 확률 분포의 추적을 통해 연속 프레임에서 특징점들의 변위를 구한다 실험 결과 제안 시스템 은 약 초당 8 프레임으로 표정 데이터를 추적하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.262-265
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• 2007

Metallic sandwich plates constructed of two face sheets and low relative density cores have lightweight characteristics and various static and dynamic load bearing functions. To predict the formability and performance of these structured materials, a computationally efficient FE-analysis method incorporating virtual equivalent projected model has been newly introduced for analysis of metallic sandwich plates. Two dimensional models using the projected shapes of 3D structures have the same equivalent elastic-plastic properties with original geometries including anisotropic stiffness, yield strength and linear hardening function. The projected shapes and virtual properties of the virtual equivalent projected model have been estimated analytically with the same equivalent properties and face buckling strength of 3D pyramidal truss core.

• 반도체디스플레이기술학회지
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• 제15권2호
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• pp.61-65
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• 2016

Facial feature detection is a fundamental function in the field of computer vision such as security, bio-metrics, 3D modeling, and face recognition. There are many algorithms for the function, active shape model is one of the most popular local texture models. This paper addresses issues related to face detection, and implements an efficient extraction algorithm for extracting the facial feature points to use on iOS platform. In this paper, we extend the original ASM algorithm to improve its performance by four modifications. First, to detect a face and to initialize the shape model, we apply a face detection API provided from iOS CoreImage framework. Second, we construct a weighted local structure model for landmarks to utilize the edge points of the face contour. Third, we build a modified model definition and fitting more landmarks than the classical ASM. And last, we extend and build two-dimensional profile model for detecting faces within input images. The proposed algorithm is evaluated on experimental test set containing over 500 face images, and found to successfully extract facial feature points, clearly outperforming the original ASM.

• International Journal of Internet, Broadcasting and Communication
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• 제14권1호
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• pp.129-135
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• 2022

Real human digital models appear more and more frequently in VR/AR application scenarios, in which real-time markerless face capture animation of personalized virtual human faces is an important research topic. The traditional way to achieve personalized real human facial animation requires multiple mature animation staff, and in practice, the complex process and difficult technology may bring obstacles to inexperienced users. This paper proposes a new process to solve this kind of work, which has the advantages of low cost and less time than the traditional production method. For the personalized real human face model obtained by 3D reconstruction technology, first, use R3ds Wrap to topology the model, then use Avatary to make 52 Blend-Shape model files suitable for AR-Kit, and finally realize real-time markerless face capture 3D real human on the UE4 platform facial motion capture, this study makes rational use of the advantages of software and proposes a more efficient workflow for real-time markerless facial motion capture of personalized 3D real human models, The process ideas proposed in this paper can be helpful for other scholars who study this kind of work.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.1335-1342
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• 2005

In this paper, there is intended to introduce the new tunnel face shape, that is concave shaped face, and discusses its effects on the tunnel stabilization. Therefore, a comparative analysis in which the stability of a concave face was compared to that of a conventional plane face on the basis of displacement patterns in the tunnel face was conducted using a model test. In order to check and confirm displacement patterns on the concave face according to the radius of curvature as well as those around the face according to lateral pressure coefficient(k), two experimental concave models, produced at a scale of 1:2 and 1:5(tunnel radius), of the forefront of the curved area extended from plane face was built and tested.

• 터널과지하공간
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• 제32권6호
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• pp.549-557
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• 2022

터널 막장관찰은 막장 암반의 불연속면과 취약한 암반상태의 조사와 평가를 포함한다. 본 연구에서는 굴착 중에 터널 막장 불연속면의 기학학적 특성을 자동으로 정량화 하기 위한 라이더 스캔 및 사진측량기법의 적용성에 대해 고찰하였다. 이러한 기법들로 구현되는 터널 막장의 3차원 모델은 인력으로 진행되는 터널 막장관찰 작업의 한계를 넘어서 일관성을 유지하며 자동으로 막장관찰상의 불연속면의 정보화를 가능하게 해준다. 본 연구를 통해 두 기법 모두 터널 막장의 불연속면 특성화에 성공적으로 적용될 수 있음을 보였다. 공학적 사용을 위한 허용 정확도 수준을 감안하여, 라이더기법이 정확도 측면에서는 사진측량기법에 비해 다소 뛰어나지만, 신뢰성 및 시간 비용 측면에서는 사진측량기법이 월등히 뛰어남을 알 수 있었다.

• 산업경영시스템학회지
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• 제44권4호
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• pp.186-192
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• 2021

Recently, the demand for more precise and demand-oriented customized spatial information is increasing due to the 4th industrial revolution. In particular, the use of 3D spatial information and digital twins which based on spatial information, and research for solving social problems in cities by using such information are continuously conducted. Globally, non-face-to-face services are increasing due to COVID-19, and the national policy direction is also rapidly progressing digital transformation, digitization and virtualization of the Korean version of the New Deal, which means that 3D spatial information has become an important factor to support it. In this study, physical objects for cities defined by world organizations such as ISO, OGC, and ITU were selected and the target of the 3D object model was limited to buildings. Based on CityGML2.0, the data collected using a drone suitable for building a 3D model of a small area is selected to be updated through road name address and building ledger, which are administrative information related to this, and LoD2.5 data is constructed and urban space. It was intended to suggest an object update method for a 3D building among data.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(3)
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• pp.193-196
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• 2000

In this paper, we present a model based 3d facial modeling method for virtual reality application using only one front of face photography. We extract facial feature using facial photography and modify mesh of the basic 3D model by the facial feature. After this , We use texture mapping for more similarity. By experiment, we know that the modeling technic is useful method for Movie, Virtual Reality Application, Game , Clothing Industry , 3D Video Conference.

• 한국멀티미디어학회논문지
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• 제10권12호
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• pp.1566-1576
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• 2007

Camera pose information from 2D face image is very important for making virtual 3D face model synchronize with the real face. It is also very important for any other uses such as: human computer interface, 3D object estimation, automatic camera control etc. In this paper, we have presented a camera position determination algorithm from a single 2D face image using the relationship between mouth position information and face region boundary information. Our algorithm first corrects the color bias by a lighting compensation algorithm, then we nonlinearly transformed the image into $YC_bC_r$ color space and use the visible chrominance feature of face in this color space to detect human face region. And then for face candidate, use the nearly reversed relationship information between $C_b\;and\;C_r$ cluster of face feature to detect mouth position. And then we use the geometrical relationship between mouth position information and face region boundary information to determine rotation angles in both x-axis and y-axis of camera position and use the relationship between face region size information and Camera-Face distance information to determine the camera-face distance. Experimental results demonstrate the validity of our algorithm and the correct determination rate is accredited for applying it into practice.

• 대한전자공학회논문지SP
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• 제41권5호
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• pp.63-69
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• 2004

본 논문에서는 포즈 변화에 강인한 얼굴 인식을 위하여 원통 모델을 이용하는 방법을 제안한다. 얼굴 모양이 원통형이라는 가정 하에 입력 영상으로부터 대상의 포즈를 예측하고, 예측된 포즈 각도만큼 포즈 변환을 실시하여 정면 얼굴 영상을 획득한다. 이렇게 획득한 정면 영상을 얼굴 인식에 적용함으로써 얼굴 인식률을 향상시킬 수 있다. 실험 결과, 포즈 변환을 통하여 인식률이 61.43%에서 93.76%로 향상되었음을 볼 수 있었으며, 보다 복잡한 3차원 얼굴 모델을 이용한 결과와 비교하였을 때 비교적 양호한 인식률을 갖는 것을 확인하였다.