• 제목/요약/키워드: 3-D shape information

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위상천이법을 이용한 삼차원 형상측정에서 위상오차 보정 (Phase error compensation for three-dimensional shape measurement based on a phase-shifting method)

  • 박윤창;안성준;강문호;권영철;안승준
    • 한국산학기술학회논문지
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    • 제10권11호
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    • pp.3023-3030
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    • 2009
  • 고속 삼차원 형상측정에서는 충분한 위상이송 스텝 수를 적용할 시간을 확보할 수 없기 때문에, 스텝 수를 축소하게 되면서 위상측정에서의 잡음이 증가되게 된다. 본 논문에서는, 다파장 PMP법에 있어서 두 파장의 비례관계를 이용하여 측정된 위상에 포함되어 있는 위상오차를 예측하고, 이를 보정하는 방법을 제안하였으며, 제안된 보정방법의 효용성을 확인하기 위한 실험이 진행되었다. 위상천이법에서 통상적으로 사용되는 스텝 수에 비해 월등히 많은 스텝의 위상 이송으로 측정하였으며, 또한 동일한 대상물을 고속 삼차원측정에서 적용되는 3-3 step의 위상 이송으로 측정하여, 두 경우에서의 측정결과를 비교하여 고속측정에서의 측정잡음을 산출하였다. 그리고, 본 논문에서 제안하고 있는 보정 방법을 측정된 맥놀이 위상과 절대위상에 적용한 결과, 각각에 있어서 90%와 17.2%의 잡음감소가 이루어지는 것으로 확인되었다.

Quantification of Fibers through Automatic Fiber Reconstruction from 3D Fluorescence Confocal Images

  • Park, Doyoung
    • 한국정보기술학회 영문논문지
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    • 제10권1호
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    • pp.25-36
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    • 2020
  • Motivation: Fibers as the extracellular filamentous structures determine the shape of the cytoskeletal structures. Their characterization and reconstruction from a 3D cellular image represent very useful quantitative information at the cellular level. In this paper, we presented a novel automatic method to extract fiber diameter distribution through a pipeline to reconstruct fibers from 3D fluorescence confocal images. The pipeline is composed of four steps: segmentation, skeletonization, template fitting and fiber tracking. Segmentation of fiber is achieved by defining an energy based on tensor voting framework. After skeletonizing segmented fibers, we fit a template for each seed point. Then, the fiber tracking step reconstructs fibers by finding the best match of the next fiber segment from the previous template. Thus, we define a fiber as a set of templates, based on which we calculate a diameter distribution of fibers.

An Evaluation Method of Taekwondo Poomsae Performance

  • Thi Thuy Hoang;Heejune Ahn
    • Journal of information and communication convergence engineering
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    • 제21권4호
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    • pp.337-345
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    • 2023
  • In this study, we formulated a method that evaluates Taekwondo Poomsae performance using a series of choreographed training movements. Despite recent achievements in 3D human pose estimation (HPE) performance, the analysis of human actions remains challenging. In particular, Taekwondo Poomsae action analysis is challenging owing to the absence of time synchronization data and necessity to compare postures, rather than directly relying on joint locations owing to differences in human shapes. To address these challenges, we first decomposed human joint representation into joint rotation (posture) and limb length (body shape), then synchronized a comparison between test and reference pose sequences using DTW (dynamic time warping), and finally compared pose angles for each joint. Experimental results demonstrate that our method successfully synchronizes test action sequences with the reference sequence and reflects a considerable gap in performance between practitioners and professionals. Thus, our method can detect incorrect poses and help practitioners improve accuracy, balance, and speed of movement.

4세대 이동통신용 하트형 빔 패턴 안테나의 설계에 관한 연구 (A study on the Heart-shape Beam Pattern Antenna for IMT-Advanced)

  • 윤현수;공진우;최병하
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2007년도 추계종합학술대회
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    • pp.857-862
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    • 2007
  • 본 논문에서는 4세대 이동통신에 적용 가능한 하트형 빔 패턴을 갖는 안테나의 설계에 관한 연구를 하였다. 제안된 구조는 하트형 빔 패턴을 갖는 기본구조와 비교하면 전체의 크기(Ground Plane)는 동일하지만, 패치의 크기는 약간 증가(약 1.3배)하였다. 임피던스 대역폭은 기본구조와 비교하여 약 258%증가하여 IMT-Advanced에 적용할 수 있는 매우 좋은 특성을 얻을 수 있었다. 안테나의 임피던스 대역폭은 약 22%(870MHz)였으며, IMT-Advanced 주파수대역 전체에 걸쳐서 8.7dBi이상의 이득을 얻었다.

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FH/BFSK을 위한 고속 스위칭용 Tracking 필터의 설계 (Design of FH/BFSK Tracking Filter for High Speed Switching)

  • 김재복;방성일
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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    • pp.405-408
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    • 2001
  • In this paper, we design tracking filter that get frequency range from 30 to 88 [MHz] for FH/BFSK communication system. This filter use for switching componet BJT. as result, This tracking filter has a insertion loss of 0.77~1.93[dB]. And it has a cutoff characteristic 30/3[dB] shape factor of 3.9~6.2[dB]. The tracking filter satisfy its specification

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3D Pattern Construction and Its Application to Tight-fitting Garments for Comfortable Pressure Sensation

  • Jeong Yeon-Hee;Hong Kyung-Hi;Kim See-Jo
    • Fibers and Polymers
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    • 제7권2호
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    • pp.195-202
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    • 2006
  • Tight-fitting clothing pattern reflecting the accurate information of the 3D body shape has been one of the challenges for garment industry, however, fitting problems still exist. The objectives of the paper is to develop a 2D pattern which fits tightly to the 3D human scan data for sports suits that need comfort and function for maximum performance. In this study, the user graphic interface application software for the semi-automatic garment pattern generation has been implemented using the triangle simplification scheme together with 2D projections of free-falling of 3D surface polygons keeping the original 3D surface area preservation. A typical application of the developed pattern to the functional body suits is presented and verification of the proposed method is also provided.

A Study on 3D Reconstruction of Urban Area

  • Park Y. M.;Kwon K. R.;Lee K. W.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.470-473
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    • 2005
  • This paper proposes a reconstruction method for the shape and color information of 3-dimensional buildings. The proposed method is range scanning by laser range finder and image coordinates' color information mapping to laser coordinate by a fixed CCD camera on laser range finder. And we make a 'Far-View' using high-resolution satellite image. The 'Far-View' is created that the height of building using DEM after contours of building extraction. The user select a region of 'Far View' and then, appear detailed 3D-reconstruction of building The outcomes apply to city plan, 3D-environment game and movie background etc.

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Non-Lambertian면의 형상복원 (3D Shape Reconstruction of Non-Lambertian Surface)

  • 김태은;이말례
    • 한국멀티미디어학회논문지
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    • 제1권1호
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    • pp.26-36
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    • 1998
  • 2차원 밝기 영상에서 3차원 정보를 얻는 문제는 컴퓨터 시각 연구에서 매우 중요한 분야를 차지하고 있다. 이러한 목적을 위해 먼저 2차원 영상을 취득할 때 카메라의 위치, 광원의 방향, 영상내 물체의 반사특성 등 본질적인 정보를 이용한다. 이중에서 물체의 표면 반사특성은 매우 중요한 단서가 된다. 과거에는 물체의 반사특성을 Lambertian 반사만을 전제하여 연구를 진행했지만 실세계의 물체는 대부분 Non-Lambertian 반사특성을 갖는다. 본 논문에서는 2차원 밝기 영상에서 물체의 반사특성을 해석하고, 반사특성 파라미터를 추정하여 물체의 형상을 복구하는 새로운 방법과 반사특성을 모르는 상황에서 신경회로망 학습에 의해 형상을 복구하는 방법을 제안한다. 물체의 반사특성은 전반사 성분과 난반사 성분을 함께 갖는 Non-Lambertian 면을 그 대상으로 하며, 이러한 반사특성은 전반사(Torrance-Sparrow) 모델과 난반사(Lambertian) 모델의 선형적인 합으로 설명될 수 있다. 본 논문에서 제안한 Photometric Matching은 주변 화소의 밝기 분포를 고려하여 참조영상과의 매칭을 통한 형상복구 알고리듬으로써 기존의 Photometric Stereo에 근본을 두고 있지만, 잡음 및 오차의 누적 정도가 향상되었다. 또한 물체의 반사특성을 모르는 상황에서 신경회로망 학습에 의한 형상복구방법을 제안한다. 이 방법은 역전파 학습알고리듬을 이용해 광원 방향에 따른 밝기값에 대해 면법선을 교사하여 형상을 결정한다.

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AUTOMATIC 3D BUILDING INFORMATION EXTRACTION FROM A SINGLE QUICKBIRD IMAGE AND DIGITAL MAPS

  • Kim, Hye-Jin;Byun, Young-Gi;Choi, Jae-Wan;Han, You-Kyung;Kim, Yong-Il
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.238-242
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    • 2007
  • Today's commercial high resolution satellite imagery such as that provided by IKONOS and QuickBird, offers the potential to extract useful spatial information for geographical database construction and GIS applications. Digital maps supply the most generally used GIS data probiding topography, road, and building information. Currently, the building information provided by digital maps is incompletely constructed for GIS applications due to planar position error and warped shape. We focus on extracting of the accurate building information including position, shape, and height to update the building information of the digital maps and GIS database. In this paper, we propose a new method of 3D building information extraction with a single high resolution satellite image and digital map. Co-registration between the QuickBird image and the 1:1,000 digital maps was carried out automatically using the RPC adjustment model and the building layer of the digital map was projected onto the image. The building roof boundaries were detected using the building layer from the digital map based on the satellite azimuth. The building shape could be modified using a snake algorithm. Then we measured the building height and traced the building bottom automatically using triangular vector structure (TVS) hypothesis. In order to evaluate the proposed method, we estimated accuracy of the extracted building information using LiDAR DSM.

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Comparison of middle-aged women's bodice pattern using 3D data -focused on the DC Suite program-

  • Cha, Su-Joung
    • 한국컴퓨터정보학회논문지
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    • 제23권1호
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    • pp.91-102
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    • 2018
  • The purpose of this study is to develop an excellent bodice prototype that is adapted to the body shape of middle-aged women using 3D measurement data. In the evaluation of appearance, S pattern 4.00, B pattern 2.80, E pattern 2.40, L pattern 1.40 were shown in order, and the best fit of S pattern was evaluated as excellent. As a result of looking at the color distribution chart to find out the amount, E pattern and S pattern were not space in the front bust, armhole, and the back waist line. The B pattern and the L pattern were marked in blue because of insufficiency space in the back neck. As a result of evaluation the amount of air gap in the clothing, the air gap of the bust was 0.12, which is the largest pattern of B. Next, the L pattern appears as a tight circle with smallest air gap in the order of the S pattern 0.096, the E pattern 0.08, and the L pattern 0.003. The S pattern was evaluated to be the most appropriate for the body shape of middle-aged women. But the waist and back were slightly tight. Middle-aged women have larger shoulder-related items and larger waist circumference. Therefore, when you set the perimeter item, you should add 1-2cm of space amount and give extra space to the circumference area.