• Title/Summary/Keyword: Connected component

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Topology Optimization of Cylinder Block using Component Mode Synthesis (구분모드합성법을 이용한 실린더블록의 위상 최적 설계)

  • 윤성호;윤영근
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.3
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    • pp.177-183
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    • 2003
  • Vibration analysis using component mode synthesis method was carried out to identify that to some extent each component contributed to the whole vibration of a powertrain consisting of several components. This analysis helped decide the component to be modified to reduce the powertrain weight, without degrading its current vibration characteristics. As a result, a cylinder block was chosen as a redesign object. Topology optimization analysis was performed to design the topology of the cylinder block whose flange connected with the transmission was chosen to be the design domain. After all, a new prototype of cylinder block was manufactured based on the analysis results for the verification experiment. It was confirmed from the analytical and experimental results that u optimally designed cylinder block had an advantage over the current one in the powertrain weight, with the powertrain vibration characteristics improved slightly.

The Parametrization and Structure Analysis for a Perspective Silhouette of a Canal Surface (Canal 곡면의 투시 윤곽곡선의 매개변수화 및 구조 분석)

  • Kim, Ku-Jin;Lee, In-Kwon
    • Journal of the Korea Computer Graphics Society
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    • v.7 no.3
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    • pp.1-7
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    • 2001
  • We present an efficient and robust algorithm to parametrize a perspective silhouette curve of a canal surface. We also detect each connected component of the silhouette. A canal surface is an envelope surface of a moving sphere with varying radii, which is defined by the center trajectory C(t) and radius function r(t) of the moving sphere. A canal surface can be decomposed to a set of characteristic circles. We derive the equations for the silhouette points on each characteristic circle, then parameterize the silhouette curve by using the equation. The sphere $S(t_*)$ with center point $C(t_*)$ and radius $r(t_*)$ intersects with the canal surface at a characteristic circle $K(t_*)$. The perspective silhouette of the sphere $S(t_*)$ from given view point consists of a circle $Q(t_*)$. By finding the values of t at which K(t) and Q(t) tangentially intersect, we detect each connected component of the silhouette curve.

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Binary Connected-component Labeling with Block-based Labels and a Pixel-based Scan Mask (블록기반 라벨과 화소기반 스캔마스크를 이용한 이진 연결요소 라벨링)

  • Kim, Kyoil
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.5
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    • pp.287-294
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    • 2013
  • Binary connected-component labeling is widely used in the fields of the image processing and the computer vision. Many kinds of labeling techniques have been developed, and two-scan is known as the fastest method among them. Traditionally pixel-based scan masks have been used for the first stage of the two-scan. Recently, block-based labeling techniques were introduced by C. Grana et. al. and L. He et. al. They are faster than pixel-based labeling methods. In this paper, we propose a new binary connected-component labeling technique with block-based labels and a pixel-based scan mask. The experimental results with various images show that the proposed method is faster than the He's which is known as the fastest method currently. The amount of performance enhancement is averagely from 3.9% to 22.4% according to the sort of the images.

Efficient Character Segmentation Technique in the Natuaral Images Containing Character Sequences (문자열을 포함하는 자연 영상에서의 효과적인 문자 추출 기법)

  • Kim, Jong-Ho;Park, Sang-Hyun;Kang, Eui-Sung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.907-910
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    • 2011
  • This paper proposes a character segmentation algorithm of steel plate images composed of adaptive binarization by the SCW (Sliding Concentric Windows) technique, the object labelling by CCA (Connected Component Analysis), and 2D projection method. The SCW technique carries out the grayscale-to-binary image conversion in consideration of local characteristics of images. The character decision algorithm followed by the labelling technique by CCA (Connected Component Analysis) determines the character area effectively reducing the noise effect. The 2D projection with horizontal and vertical directions produces a tight bounding box for a character based on the cross points. Experimental results indicate that the proposed algorithm segments the characters in steel plate images effectively. The proposed algorithm can be applied to the devices with limited resources due to its excellent performance and low complexity.

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Mobile Phone Camera Based Scene Text Detection Using Edge and Color Quantization (에지 및 컬러 양자화를 이용한 모바일 폰 카메라 기반장면 텍스트 검출)

  • Park, Jong-Cheon;Lee, Keun-Wang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.3
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    • pp.847-852
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    • 2010
  • Text in natural images has a various and important feature of image. Therefore, to detect text and extraction of text, recognizing it is a studied as an important research area. Lately, many applications of various fields is being developed based on mobile phone camera technology. Detecting edge component form gray-scale image and detect an boundary of text regions by local standard deviation and get an connected components using Euclidean distance of RGB color space. Labeling the detected edges and connected component and get bounding boxes each regions. Candidate of text achieved with heuristic rule of text. Detected candidate text regions was merged for generation for one candidate text region, then text region detected with verifying candidate text region using ectilarity characterization of adjacency and ectilarity between candidate text regions. Experctental results, We improved text region detection rate using completentary of edge and color connected component.

Analysis for the Ferroresonance on the Transformer by Overvoltage and Prevention Measures (과전압에 의한 변압기 철공진 분석 및 방지대책)

  • Yun, Dong-Hyun;Shin, Dong-Yeol;Cha, Han-Ju
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.11
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    • pp.1543-1550
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    • 2015
  • Ferroresonance is a non-linear vibrational phenomenon that is generated by the electrical interaction of the inductance component with the capacitor component of a certain capacitance as the device of the inductance component such as a transformer is saturated due to the degradation, the waveform distortion of current and voltage, and the oscillation of overcurrent and overvoltage in a system. Recently, ferroresonance was generated from the waveform distortion of current and voltage, or the overvoltage or undervoltage phenomenon caused by the nature of an electrical power system and design technology of the transformer in the three phase transformer system. Hence, in general, ferroresonance analyzed by converting to the LC equivalent circuit. However, in general, the aforementioned analytical method only applies to the resonance phenomenon that is generated by the interaction of the capacitance of bussbar and grounding, and switching as the capacitor component with PT and the transformer as the inductance component in a system. Subsequently, the condition where ferroresonance was generated since overvoltage was supplied as line voltage to the phase voltage and thus the iron core is saturated due to the interconnection between grounded and ungrounded systems could not be analyzed when single phase PT was connected in a ${\Delta}$/Y connection system. In this study, voltage swell in the configuration of grounded circuit of a step-up transformer with the ${\Delta}-{\Delta}$ connection linked to PT for control power and the ferroresonance generated by overvoltage when the line voltage of the ${\Delta}-{\Delta}$ connection was connected to the phase voltage of the grounded Y-Y connection were analyzed using PSCAD / EMTDC through the failure case of the transformer caused by ferroresonance in the system with the ${\Delta}-{\Delta}$/Y-Y connection, and subsequently, the preventive measure of ferroresonance was proposed.

A Real-time Motion Object Detection based on Neighbor Foreground Pixel Propagation Algorithm (주변 전경 픽셀 전파 알고리즘 기반 실시간 이동 객체 검출)

  • Nguyen, Thanh Binh;Chung, Sun-Tae
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.1
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    • pp.9-16
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    • 2010
  • Moving object detection is to detect foreground object different from background scene in a new incoming image frame and is an essential ingredient process in some image processing applications such as intelligent visual surveillance, HCI, object-based video compression and etc. Most of previous object detection algorithms are still computationally heavy so that it is difficult to develop real-time multi-channel moving object detection in a workstation or even one-channel real-time moving object detection in an embedded system using them. Foreground mask correction necessary for a more precise object detection is usually accomplished using morphological operations like opening and closing. Morphological operations are not computationally cheap and moreover, they are difficult to be rendered to run simultaneously with the subsequent connected component labeling routine since they need quite different type of processing from what the connected component labeling does. In this paper, we first devise a fast and precise foreground mask correction algorithm, "Neighbor Foreground Pixel Propagation (NFPP)" which utilizes neighbor pixel checking employed in the connected component labeling. Next, we propose a novel moving object detection method based on the devised foreground mask correction algorithm, NFPP where the connected component labeling routine can be executed simultaneously with the foreground mask correction. Through experiments, it is verified that the proposed moving object detection method shows more precise object detection and more than 4 times faster processing speed for a image frame and videos in the given the experiments than the previous moving object detection method using morphological operations.

Component Specification-based GPS Applications Development Process (컴포넌트 명세기반의 GPS 애플리케이션 개발 프로세스)

  • Lee, Sang Young;Lee, Yoon Hyeon
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.3
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    • pp.11-22
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    • 2012
  • GIS have expanded the use-range to the various application area with the advantage of interface environment, the various geographical operation. topological analysis by the friendly user. Early GIS software was developed as monolithic tool in which all functions packed in the same software. But, these GIS software have the problems of the high cost of constructing system, closely related system architecture and the reusability. And there is a lack of interoperability between them because most of them have their own unique data format according to their practical application fields. So Component is a unit that it is cohesive software package which is able to be developed and arranged independently and connected with another component for necessary system composition. In this paper, we analyze the requirements for component design and component specifications based on the extracted components. Commonly used to extract components from the requirements of the GPS component-based development process is presented. These components extracted by the process can be used to assemble components only. In particular, applications for developers to add features specific case without affecting the other components that can be modify the component.

Design of Ultra-broadband Microwave Amplifier Using Immittance Loci of Constant Gain (일정 이득 이미턴스 궤적을 이용한 초광대역 마이크로파 증폭기 설계)

  • 구경헌;이충웅
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.9
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    • pp.1344-1350
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    • 1990
  • A design method of ultra-broadband microwave amplifier is presented. A lossy network is represented as the combination of a serial impedance component and a parallel admittance component, and the realizable ranges of the gain and the reflection coefficients are derived with the components connected to the input, output or interstage network. The matching network has been designed by using the serial and parallel immittance loci which have the constant gain or reflection coefficients within the realizable ranges. Using the proposed method, deisgn examples of ultra-broadband amplifiers operating from dc to 12GHz frequency range are presented.

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Discriminant Analysis of Marketed Liquor by a Multi-channel Taste Evaluation System

  • Kim, Nam-Soo
    • Food Science and Biotechnology
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    • v.14 no.4
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    • pp.554-557
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    • 2005
  • As a device for taste sensation, an 8-channel taste evaluation system was prepared and applied for discriminant analysis of marketed liquor. The biomimetic polymer membranes for the system were prepared through a casting procedure by employing polyvinyl chloride, bis (2-ethylhexyl)sebacate as plasticizer and electroactive materials such as valinomycin in the ratio of 33:66:1, and were separately attached over the sensitive area of ion-selective electrodes to construct the corresponding taste sensor array. The sensor array in conjunction with a double junction reference electrode was connected to a high-input impedance amplifier and the amplified sensor signals were interfaced to a personal computer via an A/D converter. When the signal data from the sensor array for 3 groups of marketed liquor like Maesilju, Soju and beer were analyzed by principal component analysis after normalization, it was observed that the 1st, 2nd and 3rd principal component were responsible for most of the total data variance, and the analyzed liquor samples were discriminated well in 2 dimensional principal component planes composed of the 1st-2nd and the 1st-3rd principal component.