• Title/Summary/Keyword: Detection Value

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A Study on the Defect Detection of Silicon-Chip Surrounding by Ultrasonic Wave - Automatic Determination Method of Threshold Value by Image Processing - (초음파를 이용할 실리콘 칩 주위의 결함 검출에 관한 연구 - 화상처리에 의한 threshold value의 자동 결정법 -)

  • 김재열;박환규
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1991.11a
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    • pp.87-94
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    • 1991
  • This Paper is to aim the microdefect evaluation of semiconductor Package into a quantitative from NDI's image processing of ultrasonic wave. Accordingly, for the detection of delamination between the Joining condition of boundary microdefect of semiconductor packaga the result from sampling original image, histogramming, binary image or image processing of multinumerloal value is such as the follows. ([) The least limitation from the microdefect detection of the semiconductor package by surveying high ultrasonic wave seems to be about 0.8 $\mu\textrm{m}$ in degree. (2) A result of applying the image processing of multinumerical value to the semiconductor package it was possible to devide the Category into the effectiveness.

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Frameworks for NHPP Software Reliability Growth Models

  • Park, J.Y.;Park, J.H.;Fujiwara, T.
    • International Journal of Reliability and Applications
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    • v.7 no.2
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    • pp.155-166
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    • 2006
  • Many software reliability growth models (SRGMs) based on nonhomogeneous Poisson process (NHPP) have been developed and applied in practice. NHPP SRGMs are characterized by their mean value functions. Mean value functions are usually derived from differential equations representing the fault detection/removal process during testing. In this paper such differential equations are regarded as frameworks for generating mean value functions. Currently available frameworks are theoretically discussed with respect to capability of representing the fault detection/removal process. Then two general frameworks are proposed.

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A New Islanding Detection Method Based on Feature Recognition Technology

  • Zheng, Xinxin;Xiao, Lan;Qin, Wenwen;Zhang, Qing
    • Journal of Power Electronics
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    • v.16 no.2
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    • pp.760-768
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    • 2016
  • Three-phase grid-connected inverters are widely applied in the fields of new energy power generation, electric vehicles and so on. Islanding detection is necessary to ensure the stability and safety of such systems. In this paper, feature recognition technology is applied and a novel islanding detection method is proposed. It can identify the features of inverter systems. The theoretical values of these features are defined as codebooks. The difference between the actual value of a feature and the codebook is defined as the quantizing distortion. When islanding happens, the sum of the quantizing distortions exceeds the threshold value. Thus, islanding can be detected. The non-detection zone can be avoided by choosing reasonable features. To accelerate the speed of detection and to avoid miscalculation, an active islanding detection method based on feature recognition technology is given. Compared to the active frequency or phase drift methods, the proposed active method can reduce the distortion of grid-current when the inverter works normally. The principles of the islanding detection method based on the feature recognition technology and the improved active method are both analyzed in detail. An 18 kVA DSP-based three-phase inverter with the SVPWM control strategy has been established and tested. Simulation and experimental results verify the theoretical analysis.

LDO Regulator with Improved Load Regulation Characteristics and Current Detection Structure (Current Detection 구조 및 향상된 Load Regulation 특성을 가진 LDO 레귤레이터)

  • Kwon, Sang-Wook;Kong, June Ho;Koo, Yong Seo
    • Journal of IKEEE
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    • v.25 no.3
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    • pp.506-510
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    • 2021
  • In this paper, we propose an LDO that improves the load regulation change due to the current detection structure. The proposed LDO regulator adds the proposed current detection circuit to the output stage. Thereby to improve the load regulation of the delta value coming in on the output has a voltage value of an improved load Regulation characteristics than conventional LDO regulator. Using the proposed current detection structure, it was possible to improve the output change according to the change of the load current by about 60%. The proposed circuit has been simulated and verified characteristics by using a Spectre, Virtuoso simulation of Cadence.

Design of Efficient Trapezoidal Filter and Peak Value Detection Circuit for XRF Systems (XRF시스템용 효율적인 Trapezoidal 필터 및 최대값 검출 회로 설계)

  • Piao, Zheyan;Chung, Jin-Gyun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.6
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    • pp.138-144
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    • 2013
  • In XRF systems, various techniques have been developed for the synthesis of pulse shapes using digital methods instead of traditional analog methods. Trapezoidal pulse shaping algorithms can be used for digital multi-channel pulse height analysis in X-ray spectrometer systems. In this paper, an efficient trapezoidal filter architecture is presented. In addition, we present a hardware-efficient peak value detection algorithm. By the proposed algorithm, peak value detection error is decreased by half compared with the conventional algorithm. The proposed Digital Pulse Processing(DPP) algorithm is designed using Verilog HDL and implemented using an FPGA on a test board. It is demonstrated that the implemented DPP board works successfully in practical XRF systems.

Implementation of Supervisory System for Motion Information per Blocks (블록별 모션정보에 의한 감시시스템의 구현)

  • 김형균;오무송
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.1
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    • pp.74-79
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    • 2004
  • In this study, embodied supervisory system that apply motion detection technique to small web camera and detects watch picture. Motion detection technique that use pixel value of car image that use in existing need memory to store background image. Also, there is sensitive shortcoming at increase of execution time by data process of pixel unit and noise. Suggested technique that compare extracting motion information by block unit to do to have complexion that solve this shortcoming and is strong at noise. Because motion information by block compares block characteristic value of image without need frame memory, store characteristic cost by block of image. Also, can get effect that reduce influence about noise and is less sensitive to flicker etc.. of camera more than motion detection that use pixel value in process that find characteristic value by block unit.

A Tuning of Intrusin Detection Model With Fuzzy Set

  • KIM Young-Soo
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.7 no.4
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    • pp.11-21
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    • 1997
  • This paper introduces a statistical approach of intrusion detection and tunes an intrusion detection model using fuzzy ste. We describel the method of applying fuzzy set for NIDES intensity measure. By using fuzzy set, we improve the algorithm for evaluating score value of NIDES, and present a possibility of intrusion detection system.

An Algorithm for Fault Classification and Detection of Generator Dropping Using Wavelet Singular Value Decomposition (Wavelet Singular Value Decomposition을 이용한 고장 판별 및 발전기 탈락 검출 알고리즘)

  • Kim, Won-Ki;Han, Jun;Lee, Jae-Won;Kim, Chul-Hwan
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.205-206
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    • 2011
  • In this paper, algorithm for fault classification and detection of generator dropping using wavelet singular value decomposition (WSVD) is proposed. Busan area upper 345kV is modeled and generator dropping is simulated in EMTP-RV. Characteristic of generator dropping is analyzed and this algorithm is deducted by calculating WSVD in MATLAB.

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Fault Detection and Isolation using Singular Value Decomposition for Redundant Sensors System (특이치 분해를 이용한 중복 센서의 EDI 기법과 성능 분석)

  • 심덕선;양철관
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.4
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    • pp.364-370
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    • 2004
  • In this paper, we propose a FDI method, which comes from singular value decomposition of measurement matrix fur redundant sensors. We analyze the performance of the proposed FDI method by comparing with the GLT method in two ways such as FDI performance and GN&C performance. Also, we propose a GN&C performance index by combining FDI and GN&C performance.