• Title/Summary/Keyword: Alignment Reconstruction

검색결과 35건 처리시간 0.024초

자동차 블랙박스 기록 오차 보정과 경로 재구성 해석 (Compensation of Errors on Car Black Box Records and Trajectory Reconstruction Analysis)

  • 양경수;이원희;한인환
    • 한국자동차공학회논문집
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    • 제12권6호
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    • pp.182-190
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    • 2004
  • This paper presents reconstruction analysis of vehicle trajectory using records of a developed black box, and results of validation tests. For reconstruction of vehicle trajectory, the black box records the longitudinal and lateral accelerations and yaw-rate of vehicle during a pre-defined time period before and after the accident. One 2-axis accelerometer is used for measuring accelerations, and one vibrating structure type gyroscope is used for measuring yaw-rate of vehicle. The vehicle's planar trajectory can be reconstructed by integrating twice accelerations along longitudinal and lateral directions with yaw-rate values. However, there may be many kinds of errors in sensor measurements. The causes of errors are as follows: mis-alignment, low frequency offset drift, high frequency noise, and projecting 3-dimensional motion into 2-dimensional motion. Therefore, some procedures are taken for error compensation. In order to evaluate the reliability and the accuracy of trajectory reconstruction results, the black box was mounted on a passenger car. The vehicle was driven and tested along various specified lanes. Through the tests, the accuracy and usefulness of the reconstruction analysis have been validated.

내용 기반의 정렬을 통한 HDR 동영상 생성 방법 (HDR Video Reconstruction via Content-based Alignment Network)

  • 정혜수;조남익
    • 방송공학회논문지
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    • 제28권2호
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    • pp.185-193
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    • 2023
  • 최근 인터넷을 통한 동영상 제공 서비스가 확대됨에 따라 높은 품질의 온라인 컨텐츠에 대한 수요가 급증하고 있다. 그런데 넓은 동적 범위 (dynamic range)를 표현할 수 있는 high dynamic range (HDR) 컨텐츠의 공급은 수요를 따라가지 못하고 있는 실정이다. 따라서 본 논문에서는 HDR 영상 제작의 한 방법으로서, 여러 노출값에서 촬영된 프레임들로 구성된 low dynamic range (LDR) 동영상을 이용해 HDR 영상을 생성하는 방법을 제안한다. 우선, 프레임들 사이에 움직임이 존재하기 때문에 정렬 과정을 통해 이웃 프레임들을 중심 프레임에 맞추어 정렬한다. 이때 내용 (content) 기반의 정렬을 하여 정확도를 높이고, 원래 크기의 입력을 그대로 이용하는 모듈을 함께 사용하여 세부 정보도 잘 살려준다. 그러고 나서 잘 정렬된 다중 프레임들을 합쳐서 하나의 HDR 프레임으로 만들어 준다. 실험을 통해 기존 방법들에 비해 우수한 성능을 보임을 확인하였다.

3D 출력 의료용 금속 임플란트에 대한 3D 복원 (3D Reconstruction of 3D Printed Medical Metal Implants)

  • 예병훈;김구진
    • 정보처리학회논문지:소프트웨어 및 데이터공학
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    • 제12권5호
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    • pp.229-236
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    • 2023
  • 3D 출력된 의료용 임플란트(implant) 부품은 보통 표면에 결함이 발생되므로, 출력 후 표면을 검사하는 과정이 필요하다. 자동화된 표면 검사를 수행하기 위해서는 임플란트를 3D 스캔하여 점군(point cloud)과 같은 스캔 모델로 복원하는 방법이 효과적이다. 스캔 모델을 구성할 때, 임플란트는 일반적인 3D 출력 제조 부품과 다른 특성들을 가지므로, 임플란트의 형태와 재료의 특성에 대한 고려가 필요하다. 본 논문에서는 의료용 임플란트 부품의 한 종류인 금속 bone-plate의 3D 출력물에 대해 스캔 모델로 복원하는 방법을 제안한다. 다각도의 시점에서 3D 스캔을 수행하여 다수의 부분 스캔 데이터를 생성한 뒤, 이들에 대해 정렬(alignment)과 정합(merging)을 수행하여 스캔 모델로 복원한다. 또한, 실험을 통해 스캔 모델로 복원하는 과정을 보인다.

CAD/CAI 통합에 기초한 박형 단면을 가지는 항공기 터빈블레이드의 정밀측정기술 개발 (Development of Precision Inspection Technique for Aircraft Parts Having Very Thin Features on CAD/CAI Integration)

  • 박희재;안우정;김왕도
    • 대한기계학회논문집A
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    • 제20권6호
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    • pp.1743-1752
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    • 1996
  • In this paper, a precision inspection technique using CAD/CAI integration is proposed for the parts having very thin and sharp 3 dimensional curve features. The technique begings with feature reconstruction of turbine blades which have 3 dimensional combined feometry, such as splines, and thin circles. The alifnment procedures consistsb of two phases-rough and fine phases : rough phase alignment is based on the conventional 6 point5s probing on the clear cut surfacef, and fine phase alignment is based on the intial measurement on the 3 dimensional curved parts using an lterative measurement feed-back least sequares technique for alignment. Forf the analysis of profile tolerance of parts, the actual measured points are obtained by finding the closet points on the CAD geometry by the developed subdivision technique and the Tschebycheff norm is applied based on iterative fashion, giving accurate profile tolerance value. The developed inspection technique is applied to practical procedures of blade manufacturing and demonstrated high performance.

십자인대재건술 전과 후의 무릎신전근육에 대한 등속성 근력 비교 (Before and After Cruciate Ligament Reconstruction Comparison of Isokinetic Muscle Strength for Knee Extensor Muscles)

  • 문달주;김종우;황병준
    • 대한정형도수물리치료학회지
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    • 제27권2호
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    • pp.37-43
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    • 2021
  • Background: The purpose of this study is to compare and analysis the changes in strength and endurance of the knee extensor muscles after Anterior cruciate ligament reconstruction. Methods: Twelve male subjects with ligament injury were seated on Biodex and the hip joint was flexed at 110°, and torso, lower extremities, and legs were fixed using Velcro. The resistance device was placed at a point 3cm above the ankle, and measurements were taken before and a surgery at 60°/sec and 180°/sec when the knee was maximally extended. The postures ingeniously combine forward-bending poses countered with backward-bending ones. Results: There was no significant difference in the comparison of muscle strength of 60°/sec and 180°/sec before surgery. But there was a significant difference after surgery. There was significant difference in muscle endurance both before and after surgery. There was a significant difference in the pre- and post- operative comparison values of muscle strength and endurance in isokinetic movements at 60°/sec and 180°/sec during knee extension on the injured side. Conclusion: For cruciate ligament tears, Orthopedic reconstruction is recommended. Correct alignment of the knee ligament after surgery can enhance the strength and endurance of the quadriceps femoris during knee extension rejuvenated.

Identification of 1,3,6,8-Tetrahydroxynaphthalene Synthase (ThnA) from Nocardia sp. CS682

  • Purna Bahadur Poudel;Rubin Thapa Magar;Adzemye Fovennso Bridget;Jae Kyung Sohng
    • Journal of Microbiology and Biotechnology
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    • 제33권7호
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    • pp.949-954
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    • 2023
  • Type III polyketide synthase (PKS) found in bacteria is known as 1,3,6,8-tetrahydroxynaphthalene synthase (THNS). Microbial type III PKSs synthesize various compounds that possess crucial biological functions and significant pharmaceutical activities. Based on our sequence analysis, we have identified a putative type III polyketide synthase from Nocardia sp. CS682 was named as ThnA. The role of ThnA, in Nocardia sp. CS682 during the biosynthesis of 1,3,6,8 tetrahydroxynaphthalene(THN), which is the key intermediate of 1-(α-L-(2-O-methyl)-6-deoxymannopyranosyloxy)-3,6,8-trimethoxynaphthalene (IBR-3) was characterized. ThnA utilized five molecules of malonyl-CoA as a starter substrate to generate the polyketide 1,3,6,8-tetrahydroxynaphthalene, which could spontaneously be oxidized to the red flaviolin compound 2,5,7-trihydroxy-1,4-naphthoquinone. The amino acid sequence alignment of ThnA revealed similarities with a previously identified type III PKS and identified Cys138, Phe188, His270, and Asn303 as four highly conserved active site amino acid residues, as found in other known polyketide synthases. In this study, we report the heterologous expression of the type III polyketide synthase thnA in S. lividans TK24 and the identification of THN production in a mutant strain. We also compared the transcription level of thnA in S. lividans TK24 and S. lividans pIBR25-thnA and found that thnA was only transcribed in the mutant.

전방 십자 인대 파열과 슬관절 내반 변형 동반시 근위 경골 절골술과 전방 십자 인대 재건술의 동반 치료와 전방 십자 인대 재건술의 단독 치료의 비교 (Comparison of the Results between Anterior Cruciate Ligament Reconstruction alone and Combined with High Tibial Osteotomy for anterior Cruciate Ligament Ruptured Knees with Varus Alignment)

  • 곽지훈;심재앙;이용석;황철호;이범구
    • 대한관절경학회지
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    • 제17권1호
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    • pp.44-49
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    • 2013
  • 목적: 전방십자인대 파열과 슬관절 내반 변형 동반시 근위 경골 절골술과 전방십자인대 재건술의 동시 치료와 전방십자인대 재건술의 단독 치료의 결과를 비교하고자 한다. 대상 및 방법: 2005년 3월부터 2007년 2월까지 시행한 근위 경골 절골술과 전방십자인대 재건술을 동시 시행한 8예와 전방십자인대 재건술만을 단독 시행한 13예를 비교하였다. 평균 나이는 각각 34.1세(범위: 20-53), 34.9세(범위: 21-50)였으며, 평균 추시 기간은 각각 22.6개월(범위: 12-35), 20개월(범위: 13-33)이었고 임상적, 방사선학적 평가를 시행하였다. 결과: 양 군간 International Knee Documentation Committee (IKDC) 점수, Lysholm 점수, Lachman 검사, pivot shift 검사, KT-2000 관절계 검사, $30^{\circ}$, $90^{\circ}$ 전방 전위 긴장 방사선 검사 등에서 임상적, 방사선학적 유의한 차이를 보이진 않았으나, Tegner 운동 점수, Cincinnati 운동 점수는 각각 근위 경골 절골술을 동반 치료한 군이 각각 4.9점, 57.9점이었고, 단독 치료한 군이 각각 5.6점, 72.9점으로 근위 경골 절골술과 전방십자인대 재건술을 동반 치료한 군이 유의하게 낮았다(p<0.05). 결론: 전방십자인대 파열과 슬관절 내반 변형 동반시 근위 경골 절골술과 전방십자인대 재건술의 동반 치료는 전방십자 인대 재건술의 단독 치료에 비해 일상 생활에서는 차이가 없었으나 운동 능력에 있어서는 제한을 줄 수 있다고 사료된다.

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Titanium Mesh Cage for Anterior Stabilization in Tuberculous Spondylitis : Is It Safe?

  • Bak, Koang-Hum;Cheong, Jin-Hwan;Kim, Jae-Min;Kim, Choong-Hyun;Kim, Seung-Bum
    • Journal of Korean Neurosurgical Society
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    • 제40권6호
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    • pp.412-418
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    • 2006
  • Objective : The safety of titanium metal cages in tuberculous spondylitis has not been investigated. We evaluated the outcome and complications of titanium mesh cages for reconstruction after thoracolumbar vertebrectomy in the tuberculous spondylitis. Methods : There were 17 patients with 18 operations on the tuberculous spondylitis in this study. Sixteen patients were operated with anterior corpectomy and reconstruction with titanium mesh cage followed by posterior transpedicular screw fixations on same day, two pateints were operated by either anterior or posterior approach only. After the affected vertebral body resection and pus drainage from the psoas muscle, titanium mesh cage, filled with morselized autogenous bone, was inserted. All the patients had antituberculosis medication for 18 months. The degree of kyphosis correction and the subsidence of cage were measured in the 15 patients available at a minimum of 2 years. Outcome was assessed with various cross-sectional outcome measures. Recurrent infection was identified by serial ESR[Erythrocyte Sedimentation Rate] and CRP[Cross Reactive Protein]. Results : There was no complication from the use of a titanium mesh cage. Recurrent infection was not detected in any case. Average preoperative of $9.2^{\circ}$ was reduced to $-2^{\circ}$ at immediate postoperative period, and on final follow up period kyphotic angle was measured to be $4.5^{\circ}$. Postoperatively, subsidence was detected in most patients especially at ambulation period, however further subsidence was prevented by the titanium mesh cage. Osseous union was identified in all cases at the final follow-up. Conclusion : The cylindrical mesh cage is a successful instrument in restoring and maintaining sagittal plane alignment without infection recurrence after vertebrectomy for tuberculous spondylitis.

Patient-specific Guides Using 3-dimensional Reconstruction Provide Accuracy and Reproducibility in Reverse Total Shoulder Arthroplasty

  • Yoon, Jong Pil;Kim, Dong Hyun;Jung, Jae Wook;Lee, Chang-Hwa;Min, Seunggi;Lee, Hyun Joo;Kim, Hee-June
    • Clinics in Shoulder and Elbow
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    • 제22권1호
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    • pp.16-23
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    • 2019
  • Background: We aimed to evaluate whether the use of our novel patient-specific guide (PSG) with 3-dimensional reconstruction in reverse total shoulder arthroplasty (RTSA) would allow accurate and reliable implantation of the glenoid and humeral components. Methods: 20 fresh-frozen cadaveric shoulders were used. The PSG group (n=10) and conventional group (n=10) was evaluated the accuracy and reproducibility of implant positioning between before and after surgery on the computed tomography image. Results: The superoinferior and anteroposterior offset in the glenoid component were $0.42{\pm}0.07$, $0.50{\pm}0.08$ in the conventional group and $0.45{\pm}0.03$, $0.46{\pm}0.02$ in the PSG group. The inclination and version angles were $-1.93^{\circ}{\pm}4.31^{\circ}$, $2.27^{\circ}{\pm}5.91^{\circ}$ and $0.46^{\circ}{\pm}0.02^{\circ}$, $3.38^{\circ}{\pm}2.79^{\circ}$. The standard deviation showed a smaller difference in the PSG group. The anteroposterior and lateromedial humeral canal center offset in the humeral component were $0.45{\pm}0.12$, $0.48{\pm}0.15$ in the conventional group and $0.46{\pm}0.59$ (p=0.794), $0.46{\pm}0.06$ (p=0.702) in the PSG group. The PSG showed significantly better humeral stem alignment. Conclusions: The use of PSGs with 3-dimensional reconstruction reduces variabilities in glenoid and humerus component positions and prevents extreme positioning errors in RTSA.

디지털 영사식 무아레를 이용한 3차원 형상 측정과 응용에 관한 연구(II) (A Study on 3-D Shape Measurement and Application by Using Digital Projection Moire (II))

  • 유원재;강영준;노형민;이동환
    • 한국정밀공학회지
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    • 제24권5호
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    • pp.62-67
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    • 2007
  • A simple dimension measuring method for the measurement of human bust has been developed using projection moire. The 3-D data of a human bust was calculated from the 2dimensional image information obtained by the stripe using projection moire. The creation of 3-D geometric shape by digitizing real objects has been widely investigated in reverse engineering(RE). This procedure generally consists of three basic steps: data capture, data alignment and model reconstruction. In order to achieve a complete model, multiple scans must be taken and aligned.