• 제목/요약/키워드: Level Plate

검색결과 931건 처리시간 0.034초

The level set-based topology optimization for three-dimensional functionally graded plate using thin-plate spline

  • Banh, Thanh T.;Luu, Nam G.;Lee, Dongkyu
    • Steel and Composite Structures
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    • 제44권5호
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    • pp.633-649
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    • 2022
  • This paper is first implemented with the bending behavior of three-dimensional functionally graded (3DFG) plates in the framework of level set-based topology optimization (LS-based TO). Besides, due to the suitable properties of the current design domain, the thin-plate spline (TPS) is recognized as a RBF to construct the LS function. The overall mechanical properties of the 3DFG plate are assessed using a power-law distribution scheme via Mori-Tanaka micromechanical material model. The bending response is obtained using the first-order shear deformation theory (FSDT). The mixed interpolation of four elements of tensorial components (MITC4) is also implemented to overcome a well-known shear locking problem when the thickness becomes thinner. The Hamilton-Jacobi method is utilized in each iteration to enforce the necessary boundary conditions. The mathematical formulas are expressed in great detail for the LS-based TO using 3DFG materials. Several numerical examples are exhibited to verify the efficiency and reliability of the current methodology with the previously reported literature. Finally, the influences of FG materials in the optimized design are explained in detail to illustrate the behaviors of optimized structures.

Vehicle License Plate Recognition System Using the Cautious Classifier and the Weighted Instance Method (신중한 분류기와 학습 예제 가중치 조정을 이용한 차량번호판인식시스템의 인식성능 향상 방안)

  • Baik, Nam Cheol;Lee, Sang Hyup;Ryu, Kwang Ryul
    • KSCE Journal of Civil and Environmental Engineering Research
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    • 제26권4D호
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    • pp.549-551
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    • 2006
  • Vehicle License Plate Recognition System reads information from vehicles license plate using image detection devices. Of many applications provided by Vehicle License Plate Recognition System, some, such as speed enforcing system, can be problematic when the system incorrectly scans letters or numbers from a vehicle's license plate. Using Cautious Classifier avoids such problems by discarding the scanned information when the confidence level is doubted to be low. This study develops the License Plate Recognition System using Cautious Classifier and investigates effectiveness of applying the Weighted Instance Method to improve the performance of Cautious Classifier.

Behavior of Geogrid-Reinforced Soil with Cyclic plate Load Test (반복 평판재하시험을 통한 지오그리드 보강지반의 거동 특성)

  • 신은철;김두환;이상조;이규진
    • Proceedings of the Korean Geotechical Society Conference
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    • 한국지반공학회 1999년도 가을 학술발표회 논문집
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    • pp.285-292
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    • 1999
  • The cyclic plate load test were peformed to determine the behavior of reinforced soft ground with multiple layers of geogrid. Five series of test were conducted with varying the soil profile conditions which including the ground level, type of soil, and the thickness of each soil layer. The plate load test equipment was slightly modified to apply the cyclic load. Based on the cyclic plate load test results, the bearing capacity ratio(BCR), subbase modules, shear modules, the elastic rebound ratio, and reinforcing parameters are presented.

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The Method Based on Labeled Hough Transform and GLCM for License Plate Detection (어두운 환경에 강인한 번호판 추출을 위한 레이블링 Hough Transform과 GLCM 기반의 탐색 기법)

  • Park, Tae-Joon
    • Proceedings of the Korea Information Processing Society Conference
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    • 한국정보처리학회 2009년도 추계학술발표대회
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    • pp.333-334
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    • 2009
  • In this paper, I propose the novel method based on Labeled Hough transform and GLCM(Grey-Level Co-occurrence Matrix) for license plate detection. A lot of conventional methods have been proposed to detect the license plate, but those are useless in order to detect the license plate well in case of dark or unstable images. Histogram equalization is preprocessed to each image before applying this method. As a result, the license plate is detected accurately

A Study on Prediction of vibration and Sound Radiation by Plate With Four Edges Clamped (네 변이 고정된 평판의 진동 및 방사 소음 예측에 관한 연구)

  • 심현진;이정윤;오재응
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 한국소음진동공학회 2003년도 추계학술대회논문집
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    • pp.743-747
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    • 2003
  • In recent years, several studies of the practical application of active sound and vibration control have been developed to plate to plate response with various boundary conditions. This study considers vibration and sound radiation for the clamped rectangular plate. The radiation of a sound from rectangular plate can be calculated that the velocity of a vibrating plate is analyzed. The vibration formulation is based on a variation method for the vibration of the plate, and assumes no damping, no fluid loading of the structure. And the plate is exited by harmonic point force. The radiation of sound from plate is analyzed in the far field, and is calculated from the Rayleigh integral. The prediction results of vibration and sound level have proved with FEM or BEM.

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A study on the dynamic characteristics of CFRP PLATE by modal analysis method (모우드 해석법에 의한 CFRP PLATE의 동특성에 관한 연구)

  • 한응교;오재응;방태규
    • Journal of the korean Society of Automotive Engineers
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    • 제11권1호
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    • pp.44-50
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    • 1989
  • Using modal analysis method this paper examines the dynamic characteristics of composite material closely. Composite material is superior to conventional material in view of mechanical properties. So the laminate of CFRPis compared with ALPlate. As the results, the overall vibration level of CFRP is lower than that of AL Plate and is low when fiber direction is parallel to the fixed point. Also, the natural frequency of CFRP is situated in low frequency than that of AL.

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Vibration Sensing and Control of a Plate Using Optical Fiber Sensor (광섬유 센서를 이용한 평판의 진동 감지 및 제어)

  • Kim, Do-Hyung;Han, Jae-Hung;Yang, Seung-Man;Kim, Dae-Hyun;Lee, In;Kim, Chun-Gon;Hong, Chang-Sun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 I
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    • pp.459-464
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    • 2001
  • Vibration control of a plate using an optical fiber sensor and a PZT actuator is considered in this study. An aluminum plate with attached Extrinsic Fabry-Perot Interferometer (EFPI) and PZT actuator is prepared for experimental investigation. Vibration level of EFPI that can represent the mechanical strain without severe distortion is validated by forced vibration experiment. A numerical model of the plate is constructed based on the experimentally obtained frequency responses, and an optimal controller is designed for the multi-modal vibration suppression. It is found that the vibration level of the first three modes can be greatly reduced. The effect of low-pass filtering used to eliminate high frequency noise on the stability and control performance is also considered.

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Study for Accessment of Structural Stability of SAS Reactor (SAS 반응기의 구조 안전성 평가 연구)

  • 이은우;정의동;김윤춘;김종배
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 한국전산구조공학회 1995년도 가을 학술발표회 논문집
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    • pp.43-49
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    • 1995
  • Sasol Advanced Synthol Reactor was divided into two chambers by grid plate perforated with diffuser holes. The reactor has high stress level beacuse of membrane stress due to internal pressure, thermal stress due to temperature difference and local stress due to structural discontinuity at the juncture of grid plate and shell. Moreover, geometric nonlinear behaviors may appear in the grid plate because of pressure difference between two chambers. In order to survey the stress level and geometric nonlinear behaviors around grid plate, heat transfer analysis, linear static analysis and geometric nonlinear analysis were performed using NISA II developed by EMRC. This paper demonstrates the result of accessment for linear static and geometric nonlinear analysis under various load combinations.

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A study on the Optimum Modification Method by Multi-level Opimization (다단계 최적변경법에 관한 연구)

  • 박성현;박선주
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 II
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    • pp.1266-1272
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    • 2001
  • This paper discusses the multi-level optimization method in dynamic optimization problems, through stiffened plate of ship structures. In structural optimization, the computational cost increases rapidly as the number of design variables increases. And we need a great amount of calculation and time on problems of modified dynamic characteristics of large and complicated structures. In this paper, the multi-level optimization is proposed, which decreases computational time and cost. The dynamic optimum designs of stiffened plate that control the natural frequency and minimize weight subjected to constraints condition are derived. It is shown that the results are effective in the optimum modification for dynamic characteristics of the stiffened plate.

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Analysis of Noninstrumented Anterior Cervical Discectomy and Interbody Fusion in Degenerative Cervical Disease (퇴행성 경추질환에서 전방경유 추간판 절제술 및 골유합술의 결과분석)

  • Lee, Sang Weon;Song, Geun Sung
    • Journal of Korean Neurosurgical Society
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    • 제30권2호
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    • pp.180-185
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    • 2001
  • Objectives : We retrospectively studied the efficacy of anterior cervical discectomy and interbody fusion without plate fixation in degenerative cervical disease. Methods : Thirty two consecutive patients with degenerative cervical disease treated by decompression and interbody fusion(Smith-Robinson technique) without anterior cervical plating were studied for postoperative complication rate as well as the clinical and radiologic outcomes and were compared the result of ours with other reported series where the anterior cervical plating was used. Results : All cases were reviewed after average period of 13 months for the purpose of this study. There were 4 postoperative complications related to grafting. A solid fusion was obtained in all cases with single-level fusion(n=21) and 81.8 % of the cases with a two-level fusion(n=11). The overall fusion rate was 93.8 % and fusion rate per level fused was 95.3%. The clinical outcome of the patients was comparable with that in the literature, with one patient having a poor result. Comparing the result of this study with others of the anterior cervical plating, clinical outcome and fusion rate were not superior in plate fixation group in single-level fusion, but increased fusion rate and decreased graft-related complication rate were noted in multilevel fusion with plate fixation. However, the clinical outcome was not superior to noninstrumented fusion group of this study. Conclusion : These results demonstrate that anterior cervical discectomy and interbody fusion(Smith-Robinson technique) without instrumentation is safe and reliable method of single-level fusion in degenerative cervical disease. Plate fixation system doesn't seem necessary in single level fusion in degenerative cervical disease.

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