• Title/Summary/Keyword: locating

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Mechanical Error Analysis of Disk Cam Mechanisms with a Flat-Faced Follower

  • Chang Wen-Tung;Wu Long-Iong
    • Journal of Mechanical Science and Technology
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    • v.20 no.3
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    • pp.345-357
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    • 2006
  • By employing the concept of equivalent linkage, this paper presents an analytical method for analyzing the mechanical errors of disk cam mechanisms with a flat-faced follower. The resulting error equations do not really involve the location of the curvature center of the cam profile, and locating the curvature center of the cam profile is not essential. The resulting errors are significantly affected by the pressure angle, and the smaller pressure angle will result in the smaller mechanical error. In the worst case, owing to the joined effects of various design parameters, the accuracy of the follower motion may degrade considerably. For the oscillating follower case, all acceleration error functions have a sudden change at every beginning and at every end of the motion even though the theoretical follower displacement is cycloidal motion.

A Study on the Detection of Defects Using AC Current -The Effect of Frequency and Lift-off- (교류전류를 이용한 결함탐상에 관한 연구 - 주파수와 Lift-off 효과 -)

  • Kim, Hoon;Kim, Jeong-Youp;Moon, Bong-Ho
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.529-533
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    • 2001
  • NDI technique system using AC current is newly developed for inspection of defects. This technique is non-contact measurement system and can be applied for locating and sizing of surface defects in components. In this paper, the technique was applied for evaluating the location and size for 2-dimensional surface cracks and we had investigated the influence of frequency and lift-off. The results show that defects are able to detect with the variety of voltage, and the measuring voltage for the depth of defects are under the influence of the measuring frequency and the lift-off.

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Optimization of Luffing-Tower Crane Location in Tall Building Construction

  • Lee, Dongmin;Lim, Hyunsu;Cho, Hunhee;Kang, Kyung-In
    • Journal of Construction Engineering and Project Management
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    • v.5 no.4
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    • pp.7-11
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    • 2015
  • The luffing-tower crane (T/C) is a key facility used in the vertical and horizontal transportation of materials in a tall building construction. Locating the crane in an optimal position is an essential task in the initial stages of construction planning. This paper proposes a new optimization model to locate the luffing T/C in the optimal position to minimize the transportation time. A newly developed mathematical formula is suggested to calculate the transportation time of luffing T/C correctly. An optimization algorithm, the Harmony Search (HS) algorithm, was used and the results show that HS has high performance characteristics to solve the optimization problem in a short period of time. In a case study, the proposed model offered a better position for T/C than the previous heuristic approach.

The Characterization of Poly-Si Thin Film Transistor Crystallized by a New Alignment SLS Process

  • Lee, Sang-Jin;Yang, Joon-Young;Hwang, Kwang-Sik;Yang, Myoung-Su;Kang, In-Byeong
    • Journal of Information Display
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    • v.8 no.4
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    • pp.15-18
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    • 2007
  • In this paper, we investigated the SLS process to control grain boundary(GB) location in TFT channel region, and it has been found to be applicable for locating the GB at the same location in the channel region of each TFT. We fabricated TFT by applying a new alignment SLS process and compared the TFT characteristics with a normal SLS method and the grain boundary location controlled SLS method. Also, we have analysed degradation phenomena under hot carrier stress conditions for n-type LDD MOSFETs.

An Algorithm for Illuminating a Convex Polygon with Two Equal Floodlights (두개의 동일한 탐조등으로 볼록다각형을 비추는 알고리즘)

  • Kim, Sung-Kwon;Shin, Chan-Su
    • Journal of KIISE:Computer Systems and Theory
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    • v.27 no.4
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    • pp.416-419
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    • 2000
  • Let G be an n-vertex convex polygon whose vertices are in general position. We consider an illumination problem of locating two floodlights on the boundary of G, which illuminates G and whose larger angle is as small as possible. We present an O($n^2$) time algorithm under the extended real-RAM model.

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Detection and Location of Partial discharge in Transformers Using Logoski coil and Ultrasonic sensor (로고스키 코일과 초음파 센서를 이용한 변압기내 부분방전 탐지 및 위치검출)

  • Kwak, Hee-Ro;Kim, Jae-chul;Kim, Eung-Sang;Han, Min-Koo;Kwan, Tae-Won;Yoon, Young-Beum
    • Proceedings of the KIEE Conference
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    • 1990.07a
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    • pp.279-282
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    • 1990
  • This paper describes an nstrument for the detection and geometric location of partial discharge(PD) sources in transformers. This instrument measures electric current pulses and ultrasonic pulses simultaneously, counts the number of electrical pulse and determines the geometric location of PD in transformers. It was found that there is a relationship between partial discharge magnitude and pulse repetition rate when the applied test voltage and oil temperature were varied. Through the laboratory test using model transformer, it was clarified that this detector could be used, satisfactory for detecting and locating of PD in the transformer.

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Automation for Oyster Hinge Breaking System

  • So, J.D.;Wheaton, F.W.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.658-667
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    • 1996
  • A computer vision system was developed to automatically detect and locate the oyster hinge line, one step in shucking an oyster. The computer vision system consisted of a personal computer, a color frame grabber, a color CCD video camera with a zoom lens, two video monitor, a specially designed fixture to hold the oyster, a lighting system to illuminate the oyster and the system software. The software consisted of a combination of commercially available programs and custom designed programs developed using the Microsoft CTM . Test results showed that the image resolution was the most important variable influencing hinge detection efficiency. Whether or not the trimmed -off-flat-white surface area was dry or wet, the oyster size relative to the image size selected , and the image processing methods used all influenced the hinge locating efficiency. The best computer software and hardware combination used successfully located 97% of the oyster hinge lines tested. This efficienc was achieve using camera field of view of 1.9 by 1.5cm , a 180 by 170 pixel image window, and a dry trimmed -off oyster hinge end surface.

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Fuzzy Estimation for Fault Location

  • Tipsuwanporn, V.;Tuppadung, Y.;Suesut, T.;Rukkaphan, S.;Junkrob, N.
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.453-453
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    • 2000
  • This paper presented Fuzzy logic application to Electrical power system analysis for fault location estimation in distribution lines and apply the Power system theory to be fuzzy logic database. The case study referred to the Overhead distribution line of the Provincial Electricity Authority (PEA.), Thailand which mostly the distribution line of PEA. are Radial schemes. These benefits include reduced outage time, help in locating momentary faults, enhance safety to the line crews and provide notification of an outage without receiving calls from the consumer, Which these benefits also increase Reliability, Stability and Efficiency.

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A Study on the Power Monitoring System using GPS for Accurate Time Synchronization (GPS 정밀시각동기를 이용한 전력계통 모니터링 시스템에 관한 연구)

  • 김혁수;전성준;김기택
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.285-285
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    • 2000
  • A continuous and reliable electrical energy supply is the objective of any power system operation. A transmission line is the part of the power system where faults are most likely to happen. This paper describes the use of wavelet transform for analyzing power system fault transients in order to determine the fault location. Synchronized sampling was made possible by precise time receivers based on GPS time reference, and the sampled data were analyzed using wavelet transform. This paper describes a fault location monitoring system and fault locating algorithm with GPS, DSP processor, and data acquisition board, and presents some experimental results and error analysis.

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Locating Chest Boundary in Sequential Images by Snakes (Snakes를 이용한 흉부 연속영상의 외부윤곽검출)

  • Hwang, Y.H.;Choi, W.Y.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.236-239
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    • 1997
  • Snakes is an active contour model or representing image contours. To detect chest boundary on thoracic MRI sequences, we proposed a method based on modified greedy algorithm. Because thoracic MRI sequences have a spatial correlation, we added energy term related with spatial correlation to Snakes energy formulation. A measure of shape similarity called the BMD was used to evaluate the accuracy of the algorithm. The average BMD value or the modified algorithm's result is higher than greedy algorithm's.

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