• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.3
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• pp.24-32
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• 2007

Variable message sign (VMS), which is used for providing real-time information on traffic conditions and accident occurrences, is one of the important components of intelligent transportation systems. It is essential that the scheme of VMS message phase and duration should be designed with the consideration of drivers' message reading time that will be depended on various causal factors, such as the amount of VMS messages, drivers' travel speed, and geometric conditions. However, there have been not much efforts to explore the relationships between the drivers' message reading time and the above causal factors. Driving simulator experiments were conducted to obtain drivers' message reading time with respect to the amount of VMS messages, drivers' travel speed, and different geometric conditions. Regression modeling techniques were applied to develop an estimation model for drivers' message reading time. Probabilistic outcomes of the proposed model would be greatly utilized to design proper VMS message phase and duration.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.343-344
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• 2010

markerless system to a two-dimensional imaging is used to estimate the depth map as a stereo vision system uses expensive equipment. We estimate the depth map from monocular image enhancement and object extracted relative to the vanishing point is estimated depth map. Augmented objects in order to get better virtual immersion depending on the distance of the objects should be drawn in different sizes. In this paper, creating images obtained from the vanishing point, and in-depth information on the augmented object, augmented with different sizes and improved engagement of inter-object interaction.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.3C
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• pp.419-425
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• 2004

This paper presents a new method which is calculated to use only three vanishing points in order to compute the dimensions of object and its pose from a single image of perspective projection taken by a camera. Our approach is to only compute three vanishing points without informations such as the focal length and rotation matrix from images in the case of perspective projection. We assume that the object can be modeled as a linear function of a dimension vector v. The input of reconstruction is a set of correspondences between features in the model and features in the image. To minimize each the dimensions of the parameterized models, this reconstruction of optimization can be solved by standard nonlinear optimization techniques with a multi-start method which generates multiple starting points for the optimizer by sampling the parameter space uniformly.

• Journal of the Korean Orthopaedic Association
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• v.54 no.6
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• pp.519-527
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• 2019

Purpose: To evaluate the treatment result in polyostotic fibrous dysplasia classified according to the involvement of the femoral head. Materials and Methods: Twenty-three patients from March 1987 to March 2014 were reviewed retrospectively. Patients with no involvement of the physeal scar in the femoral head were classified as Type I, and those with involvement of the physeal scar were classified as Type II. A plain radiograph was used to measure the femoral neck shaft angle, articulo-trochanteric distance (ATD), and anterior bowing through the lateral view. A teleoroentgenogram of the lower limb was used to measure the leg length discrepancy and lower extremity mechanical axis. The pre- and postoperative femoral neck-shaft angle and ATD were compared to assess the degree of correction of the deformity. Results: Among a total of 46 cases (23 patients), 28 cases (23 patients) had lesions in the proximal femur. Type I were 16/28 cases (15/23 patients) and Type II were 12/28 cases (9/23 patients). The preoperative proximal femoral neck-shaft angle was 116.8° in Type I and 95.3° in Type II. The ATD was 12.08 mm in Type I and -5.54 mm in Type II. The deformity correction showed significant improvement immediately after surgery, the deformity correction was lost in Type II (neck shaft angle Type I: 133.8°-130.8°, Type II: 128.6°-116.9°, and ATD Type I: 17.66-15.72 mm, Type II: 7.44-4.16 mm). The extent of anterior bowing was 12.74° in Type I and 20.19° in Type II. The mean differences of 12 mm between the 9 patients who showed a leg length discrepancy and the lower extremity mechanical axis showed 4 cases of lateral deviation and 7 cases of medial deviation. Conclusion: In polyostotic fibrous dysplasia, when the femur head is involved, the femur neck shaft angle, ATD, and anterior bowing of the femur had more deformity, and the postoperative correction of deformity was lost, suggesting that the involvement of the femoral head was an important factor in the prognosis of the disease.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.07a
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• pp.70-73
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• 2010

최근 IT 기술이 융합된 지능형 자동차 기술에 대한 관심이 높아짐에 따라 이에 대한 연구가 활발히 진행되고 있다. 차선 검출은 지능형 자동차의 주요 과제인 첨단 안전자동차 기술의 핵심적인 부분으로 국내외에서 다양한 방법들에 대한 연구가 진행되었다. 차량의 안전을 향상시키기 위해서는 충분한 제동거리 확보가 가능한 거리까지 정확하고 빠른 차선 검출이 이루어져야 한다. 기존의 경계선 검출기반 차선 검출은 소실점 근처에서 경계선 검출이 이루어지지 않았다. 이는 차선과 도로의 색이 잘 구분되지 않는 채널을 사용하는 문제에서 기인한다. 따라서 본 논문에서는 선형 판별 분석 기법을 이용하여 차선과 도로 색을 가장 잘 구분할 수 있는 RGB 가중치를 계산하여 이로부터 projection 영상을 만들고, 변환한 영상에서 경계선 검출을 수행함으로써 보다 정확한 경계선 검출 결과를 얻는 방법을 제안한다. 제안한 방법으로 얻은 영상과 기존의 흑백 영상에 동일한 경계선 검출기를 적용하여 성능을 비교하고, 이를 적용한 차선검출 실험결과를 제시한다.

• Journal of the Korea Computer Graphics Society
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• v.23 no.4
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• pp.11-19
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• 2017

We propose a new pipeline of fluid surface reconstruction that incorporates hybrid SDF(signed distance fields) and adaptive fluid surface techniques to finely reconstruct liquid-solid mixed surfaces. Previous particle-based fluid simulation suffer from a noisy surface problem when the particles are distributed irregularly. If a smoothing scheme is applied to reduce the problem, sharp and detailed features can be lost by over-smoothing artifacts. Our method constructs a hybrid SDF by combining signed distance values from the solid and liquid parts of the object. We also proposed a method of adaptively reconstructing the surface of the fluid to further improve the overall efficiency. This not only shows the detailed surface of the solid and liquid parts, but also the detail of the solid surface and the smooth fluid surface when both materials are mixed. We introduce the concept of guiding shape and propose a method to get signed distance value quickly. In addition, the hybrid SDF and mesh reconstruction techniques are integrated in the adaptive framework. As a result, our method improves the overall efficiency of the pipeline to restore fluid surfaces.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.1229-1231
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• 2022

RGBD 영상은 다양한 3 차원 비전 연구에서 유용하게 사용되며 고품질 RGBD 영상을 취득하기 위한 많은 연구들이 수행되었다. 기존의 영상 생성 연구들은 주로 좁은 FoV(Field of View) 영상을 사용하여서 전체 장면 중 상당 부분이 소실된 영상에 대한 정보를 생성한다. 본 논문에서는 기존의 좁은 FoV 영상으로부터 360 도 전방향 RGBD 영상을 생성하는 기법을 제안한다. 오버랩 되지 않는 4 장의 소수 영상으로부터 전체 파노라마 영상에 대해서 상대적인 FoV 를 추정하고, 360 도 RGBD 영상을 동시에 생성하는 적대적 생성 신경망 기반의 영상 생성 네트워크이다. 360 도 영상의 특징을 반영하도록 설계하여서 개선된 성능을 보인다.

• Journal of the Institute of Convergence Signal Processing
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• v.7 no.3
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• pp.108-115
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• 2006

In this paper, a recognition algorithm of the straight line components of lane markings and an obstacle in the travelling lane region is proposed. This algorithm also involve the pitching error correction algorithm due to traveling vehicle's fluctuation. In order to reduce their error a practical road image modelling algorithm using V.F. model and camera calibration procedure are suggested to adapt the geometric variations. It is obtained the 3D world coordinate data by the 2D road images. In experimental test, we showed that this algorithm is available to recognize lane markings and an obstacle in the traveling lane.

• The Journal of the Korea Contents Association
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• v.11 no.4
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• pp.11-17
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• 2011

This paper aims to realize the information of a subject existing in a still image with objective values. To attain the goal, this research takes the vanishing point that a 2D still image has as the basis and recomposes the still image into a 3D image using a 3D program. Also, in order to set up the axis of the camera necessary to recompose a 3D image, this paper used the lens angle of view that the image has and floor patterns as well. The 3D image completed in this way can measure the size and distance of all subjects in the floor patterns if the size value of a particular reference subject is known, and through this, it can be possible to acquire basic information of a subject that can be either a criminal or a clue in the images of CCTVs or some criminal scene.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.1
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• pp.110-118
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• 2022

Multiple tooth loss can cause disharmonious occlusial plane, loss of vertical dimension and deflection of mandibular movement. Therefore, restoring proper vertical dimension and occlusion in the centric relation is an important treatment goal. Implant-assisted removable partial denture is a recently used clinical technique, because it increases patient satisfaction by improving retention, support, and stability of conventional denture. The objective of this article is to present a case report describing the fabrication of treatment denture and implant assisted removable partial denture using previously placed implants for a patient with partial loss of posterior support and anterior stop.