• Title/Summary/Keyword: 분할판

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A Surface Panel Method for the Analysis of Hydrofoils wih Emphasis on Local Flows around the Leading and Trailing Edges (앞날 및 뒷날 유동 특성을 고려한 표면양력판 이론에 의한 2차원수중익 단면해석)

  • Jin-Tae,Lee
    • Bulletin of the Society of Naval Architects of Korea
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    • v.26 no.3
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    • pp.41-50
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    • 1989
  • A basic formulation of the panel method, which is based on the potential field formulation, is reviewed for the case of two-dimensional hydrofoil problems. Numerical procedures to improve the computational efficiency of the panel method are suggested. By investigating local behavior of the flow around the trailing edge, a wedge type Kutta condition is formulated. By subdividing the trailing edge panels, where dipole strengths of the subdivided panels follow the local behavior of the potential values of the flow outside a wedge, the circulation around a hydrofoil is calculated accurately with a relatively small number of panels. The subdividing technique to improve the accuracy of the numerical Kutta condition is proved to be efficient. A local behavior of the flow around the leading edge is also investigated. By matching the flow around the leading edge with that around a parabola, a very accurate velocity distribution is obtained with relatively small number of panels. An accurate prediction of the stagnation point and the pressure distribution near the leading edge may contribute to improve the accuracy of cavity predictions and boundary layer calculations around hydrofoils.

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An Improvement of the State Assessment for Concrete Floor Slab by Damage Type Breakdown (손상유형 분할에 의한 콘크리트 바닥판의 상태평가 개선)

  • Hwang, Jin Ha;An, Seoung Su
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.12 no.2
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    • pp.139-148
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    • 2008
  • The direct inspection of the outward aspects by field engineers is the important and critical part for structural safety assessment according to the related reports. This study presents an improved method of the state assessment for concrete floor slab by separating and evaluating the individual damage types. First, the various types of damage symptoms are separated, which have been included and dealt in a group. Secondly, they are weighted and scored independently based on the present guide and references. Overall procedures other than the above are retained as same as possible to avoid the confusion. The proposed method is applied and tested to a performed assessment project for a bridge for validation. The result shows that it is reasonable and applicable in respect that it is able to make up for the controversial points of the present guide revealed in practices. Careful check of excessively deteriorated parts in addition to the reasonable assessment of system by this method grants the structural repair and reinforcement propriety and economy, and assures of more safety. Twofold appraisal of this approach expands the applicable areas of value engineering to the structural maintenance.

Detection of Various Sized Car Number Plates using Edge-based Region Growing (에지 기반 영역확장 기법을 이용한 다양한 크기의 번호판 검출)

  • Kim, Jae-Do;Han, Young-Joon;Hahn, Hern-Soo
    • Journal of KIISE:Software and Applications
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    • v.36 no.2
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    • pp.122-130
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    • 2009
  • Conventional approaches for car number plate detection have dealt with those input images having similar sizes and simple background acquired under well organized environment. Thus their performance get reduced when input images include number plates with different sizes and when they are acquired under different lighting conditions. To solve these problem, this paper proposes a new scheme that uses the geometrical features of number plates and their topological information with reference to other features of the car. In the first step, those edges constructing a rectangle are detected and several pixels neighboring those edges are selected as the seed pixels for region growing. For region growing, color and intensity are used as the features, and the result regions are merged to construct the candidate for a number plate if their features are within a certain boundary. Once the candidates for the number plates are generated then their topological relations with other parts of the car such as lights are tested to finally determine the number plate region. The experimental results have shown that the proposed method can be used even for detecting small size number plates where characters are not visible.

Designed of Intelligent Solar Tracking System using Fuzzy State-Space Partitioning Method (퍼지 상태 공간 분할 기법을 이용한 지능형 태양광 추적시스템 설계)

  • Kim, Gwan-Hyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.10
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    • pp.2072-2078
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    • 2011
  • In photovoltaic(PV) system, for obtaining maximum efficiency of solar power systems, the solar tracking system must be controlled to match position of the sun. In this paper, we design the solar tracking system to track movement of the sun using CdS sensor modules and to determine direction of the sun under shadow of directions. In addition, for an intelligent computation in tracking of the sun, a fuzzy controller is allocated to space avaliable for splitting area of fuzzy part for the fuzzy input space(grid-type fuzzy partition) in which a fuzzy grid partition divides fuzzy rules bases. As well, a simple model of solar tracking system is designed by two-axis motor control systems and the 8-direction sensor module that can measure shadow from CdS sensor modules by matching of axis of CdS modules and PV panels. We demonstrate this systems is effective for fixed location and moving vessels and our fuzzy controller can track the satisfactorily.

Implementation of the Embedded Screen Control System using Image-Based Mobile Network (이미지기반 모바일 네트워크를 이용한 임베디드 전광판의 원격제어 시스템의 구현)

  • Lee Yeon-Seok
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.5
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    • pp.970-974
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    • 2006
  • In his paper, a remote screen control system by mobile networks on embedded system is implemented. For this system a server program is ported on the embedded system connected to the internet. And on the side of a mobile phone, a client program is ported using general virtual machine. The embedded system can display the image from the mobile phone on its LCD. In the implemented embedded system, the image data from GVM emulator is sent to the system for display on its LCD. The realization of the proposed embedded system can display the image from a working mobile phone.

Fast algorithm for Traffic Sign Recognition (고속 교통표시판 인식 알고리즘)

  • Dajun, Ding;Lee, Chanho
    • Journal of IKEEE
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    • v.16 no.4
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    • pp.356-363
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    • 2012
  • Information technology improves convenience, safety, and performance of automobiles. Recently, a lot of algorithms are studied to provide safety and environment information for driving, and traffic sign recognition is one of them. It can provide important information for safety driving. In this paper, we propose a method for traffic sign detection and identification concentrating on reducing the computation time. First, potential traffic signs are segmented by color threshold, and a polygon approximation algorithm is used to detect appropriate polygons. The potential signs are compared with the template signs in the database using SURF and ORB feature matching method.

Traffic Light and Speed Sign Recognition by using Hierarchical Application of Color Segmentation and Object Feature Information (색상분할 및 객체 특징정보의 계층적 적용에 의한 신호등 및 속도 표지판 인식)

  • Lee, Kang-Ho;Bang, Min-Young;Lee, Kyu-Won
    • The KIPS Transactions:PartB
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    • v.17B no.3
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    • pp.207-214
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    • 2010
  • A method of the region extraction and recognition of a traffic light and speed sign board in the real road environment is proposed. Traffic light was recognized by using brightness and color information based on HSI color model. Speed sign board was extracted by measuring red intensity from the HSI color information We improve the recognition rate by performing an incline compensation of the speed sign for directions clockwise and counterclockwise. The proposed algorithm shows a robust recognition rate in the image sequence which includes traffic light and speed sign board.

Study on Performance Evaluation of Automatic license plate recognition program using Emgu CV (Emgu CV를 이용한 자동차 번호판 자동 인식 프로그램의 성능 평가에 관한 연구)

  • Kim, Nam-Woo;Hur, Chang-Wu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.6
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    • pp.1209-1214
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    • 2016
  • LPR(License plate recognition) is a kind of the most popular surveillance technology based on accompanied by a video and video within the optical character recognition. LPR need a many process. One is a localization of car license plates, license plate of size, space, contrast, normalized to adjust the brightness, another is character division for recognize the character optical character recognition to win the individual characters, character recognition, the other is phrase analysis of the shape, size, position by year, the procedure for the analysis by comparing the database of license plate having a difference by region. In this paper, describing the results of performance of license plate recognition S/W, which was implemented using EmguCV, find the location, using the tesseract OCR, which are well known to an optical character recognition engine of open source, the characters of the license plate image capturing angle of the plate, image size, brightness.

유한요소법을 이용한 조선조식 종형 구조물의 동적 해석

  • 정석주;공창덕;염영하
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.9 no.3
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    • pp.309-318
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    • 1985
  • 본 논문에서는 종형 구조물의 특미인 비대칭성을 고헌할 수 있고 굽힘에너지 (flexural energy)와 확장에너지(extension energy)를 모두 고헌하여 유한요소의 분할 이 용역한 사변형과 삼각형 판-셸 유한요소를 사용하였다.

Performance Evaluation of Clustering Methods of Feature Vectors in Vehicle Plate Recognition Systems based on Modular Neural Network (모듈라 신경망에 기반한 번호판 인식시스템의 특징벡터 클러스터링 방법에 따른 성능평가)

  • 박창석;김병만;서병훈;이광호
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04c
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    • pp.313-315
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    • 2003
  • 분할 및 합병 개념에 바탕을 둔 모듈라 신경망이 자동차 번호판 문자 인식에서 단일 신경망 사용 보다 학습 질 측면이나 학습 속도 면에서 좋은 결과를 보였다. 본 논문에서는 번호판 인식을 위한 모듈라 신경망 구성 시, 특징 벡터 클러스터링 방법에 따른 모듈라 신경망의 성능을 평가하였다. K-means Clustering 알고리즘을 이용하여 유사한 특징 벡터를 그룹핑하는 방법과 본 논문에서 제안한 알고리즘을 사용하여 유사하지 않는 특징 벡터들을 그룹핑하는 방법 각각을 구현하여 실험하였다. 실험결과, 유사하지 않는 특징 벡터들로 모듈라 신경망을 구성할 경우가 그렇지 않은 경우보다 좋은 인식 결과를 보였다.

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