• 제목/요약/키워드: control threshold

검색결과 1,145건 처리시간 0.032초

전기제어 설비의 출력 안정화를 위한 가우시안 접근법 (A Gaussian Approach in Stabilizing Outputs of Electrical Control Systems)

  • 바스넷버룬;방준호;유인호;김태형
    • 전기학회논문지
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    • 제67권11호
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    • pp.1562-1569
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    • 2018
  • Sensor readings always have a certain degree of randomness and fuzziness due to its intrinsic property, other electronic devices in the circuitry, wires and the rapidly changing environment. In an electrical control system, such readings will bring instability in the system and other undesired events especially if the signal hovers around the threshold. This paper proposes a Gaussian-based statistical approach in stabilizing the output through sampling the sensor data and automatic tuning the threshold to the range of multiple standard deviations. It takes advantage of the Central limit theorem and its properties assuming that a large number of sensor data samples will eventually converge to a Gaussian distribution. Experimental results demonstrate the effectiveness of the proposed algorithm in completely stabilizing the outputs over known filtering algorithms like Exponential smoothing and Kalman Filter.

클럭 조절 방식의 임계 클럭 조절형 LM-128 이진 수열 발생기 제안 (A proposal of binary sequence generator, Threshold Clock-Controlled LM-128)

  • 조정복
    • 한국정보통신학회논문지
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    • 제19권5호
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    • pp.1104-1109
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    • 2015
  • 디지털 콘텐츠의 급속한 발전으로 미래의 요구에 부합할 수 있는 고속의 보안 암호 알고리즘 설계는 중요하다. 본 논문에서는 기존의 수열 발생기 보다 더 높은 처리율을 갖는 자체 수축형 LM-128 합산 수열 발생기를 제안한다. 임계 클럭 조절형 LM-128의 설계하고 구현하여 더 낮은 클럭 사이클을 가져서 더 높은 키 수열 발생 속도를 증명한다. 제안된 임계 클럭 조절형 발생기는 128비트 비밀 키와 초기 벡터를 갖는 내부 상태 256비트로 구성되어진다. 128-비트의 보안 수준의 암호는 고화질 및 고품질의 디지털 콘텐츠 보안에 적합하다.

Facial Feature Recognition based on ASNMF Method

  • Zhou, Jing;Wang, Tianjiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제13권12호
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    • pp.6028-6042
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    • 2019
  • Since Sparse Nonnegative Matrix Factorization (SNMF) method can control the sparsity of the decomposed matrix, and then it can be adopted to control the sparsity of facial feature extraction and recognition. In order to improve the accuracy of SNMF method for facial feature recognition, new additive iterative rules based on the improved iterative step sizes are proposed to improve the SNMF method, and then the traditional multiplicative iterative rules of SNMF are transformed to additive iterative rules. Meanwhile, to further increase the sparsity of the basis matrix decomposed by the improved SNMF method, a threshold-sparse constraint is adopted to make the basis matrix to a zero-one matrix, which can further improve the accuracy of facial feature recognition. The improved SNMF method based on the additive iterative rules and threshold-sparse constraint is abbreviated as ASNMF, which is adopted to recognize the ORL and CK+ facial datasets, and achieved recognition rate of 96% and 100%, respectively. Meanwhile, from the results of the contrast experiments, it can be found that the recognition rate achieved by the ASNMF method is obviously higher than the basic NMF, traditional SNMF, convex nonnegative matrix factorization (CNMF) and Deep NMF.

Robust Lip Extraction and Tracking of the Mouth Region

  • Min, Duk-Soo;Kim, Jin-Young;Park, Seung-Ho;Kim, Ki-Jung
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -2
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    • pp.927-930
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    • 2000
  • Visual features of lip area play an important role in the visual speech information. We are concerned about correct lip area as region of interest (ROI). In this paper, we propose a robust and fast method for locating the mouth corners. Also, we define a region of interest at mouth during speech. A method, which we have used, only uses the horizontal and vertical image operators at mouth area. This searching is performed by fitting the ROI-template to image with illumination control. Most of the lip extraction algorithms are dependent on luminosity of image. We just used the binary image where the variable threshold is applied. The variable threshold varies to illumination condition. In order to control those variations, the gray-tone is converted to binary image by threshold, which is obtained through Multiple Linear Regression Analysis (MLRA) about divided 2D special region. Thus we obtained the region of interest at mouth area, which is the robust extraction about illumination. A region of interest is automatically extracted.

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Threshold Voltage Control of Pentacene Thin-Film Transistor with Dual-Gate Structure

  • Koo, Jae-Bon;Ku, Chan-Hoe;Lim, Sang-Chul;Lee, Jung-Hun;Kim, Seong-Hyun;Lim, Jung-Wook;Yun, Sun-Jin;Yang, Yong-Suk;Suh, Kyung-Soo
    • Journal of Information Display
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    • 제7권3호
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    • pp.27-30
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    • 2006
  • This paper presents a comprehensive study on threshold voltage $(V_{th})$ control of organic thin-film transistors (OTFTs) with dual-gate structure. The fabrication of dual-gate pentacene OTFTs using plasma-enhanced atomic layer deposited (PEALD) 150 nm thick $Al_{2}O_{3}$ as a bottom gate dielectric and 300 nm thick parylene or PEALD 200 nm thick $Al_{2}O_{3}$ as both a top gate dielectric and a passivation layer was investigated. The $V_{th}$ of OTFT with 300 nm thick parylene as a top gate dielectric was changed from 4.7 V to 1.3 V and that with PEALD 200 nm thick $Al_{2}O_{3}$ as a top gate dielectric was changed from 1.95 V to -9.8 V when the voltage bias of top gate electrode was changed from -10 V to 10 V. The change of $V_{th}$ of OTFT with dual-gate structure was successfully investigated by an analysis of electrostatic potential.

Tuning the Parameters for the Decision Making System in Order to Define Athlete's Aerobic and Anaerobic Thresholds

  • Ketola, Jaakko;Saastamoinen, Kalle;Turunen, Esko
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.317-320
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    • 2004
  • In this work we have managed to find parameters for defining athlete's aerobic and anaerobic thresholds. Thresholds which are of vital importance for top athletes. It is shown how differential evolution and different similarity measures has been used to tune computational model for threshold definitions. From our results it is obvious that the use of right parameter values for this kind expert system is of vital importance.

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인버스 히스토그램을 이용한 다수의 이차원 물체 인식 (The rocognition of two-dimensional objects using the inverse histogram)

  • 박성혁;고명삼
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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    • pp.331-336
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    • 1986
  • Because the threshold technique using the histogram of intensity is the most attractive for segmentation in the sense of fast image processing, this paper defined the new function of inverse histogram of intensity and found out a threshold by means of it. The segmented errors are removed by regulating a scan size of blob coloring. Blob-coloring algorithm presented by [6] was reproved for good performance i.e., no change of feature in bolobs after blob coloring. The ratio of successful recognition was about 85 percents.

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Estimating the Queue Length Distribution of ATM multiplexer using Threshold Bootstrap

  • 김윤배
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 1999년도 추계학술대회 논문집
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    • pp.62-62
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    • 1999
  • In this paper, we propose a new technique of estimating tail of steady-state queue length distribution; Pr(Q>q), fo ATM multiplexer. Pr(Q>q) is a fundamental measure of network congestion. Assessing Pr(Q>q) properly is crucial for design and control of ATM networks. Data traffic pattern of high-speed networks is highly correlated and bursty. Estimating Pr(Q>q) is very difficult because of correlation and burstiness. We estimate entropy(rate-function) using large deviation principles and threshold bootstrap. Simulation studies are conducted to compare the performance of an existing method and our new method.

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ATM망에서 효율적인 문턱 값 기반 호 수락 제어 (An Effective Threshold based Call Admission Control in ATM Networks)

  • 김상철;고성택
    • 융합신호처리학회 학술대회논문집
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    • 한국신호처리시스템학회 2000년도 하계종합학술대회논문집
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    • pp.33-36
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    • 2000
  • ATM 트래픽 제어를 위해서 효과적인 호 수락 제어 방법이 필요하다. 이것은 호 수락 과정에서 서로 다른 종류의 서비스들에 대해서 높은 이용률과 공정성을 제공하여야 한다. 본 논문에서는 호 수락의 공정성과 대역폭 이용률을 높이기 위하여 링크에 문턱 값을 적용한 새로운 CST(Complete Sharing with Threshold)알고리즘을 제안하였으며 부하와 문턱 값의 변화에 따른 성능을 분석하였다.

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음성재생 속도 제어를 위한 활성화 영역 검출방법 (An Active Region Detection Method for The Speech Playback-speed Control)

  • 유덕현;김동현;전준현
    • 대한전자공학회논문지SP
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    • 제49권3호
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    • pp.98-105
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    • 2012
  • 본 논문은 고품질을 갖는 음성재생 속도제어를 위한 새로운 방법을 다루었다. 제안 방법은 재생 속도에 따른 음성 신호의 활성화 영역을 검출하는 가변적 임계필터링 솔루션을 제공하였다. 임계필터링을 위한 임계값은 주어진 배속에 따라 재생되는 음성 신호 내의 각 프레임의 통계(평균과 표준편차)에 의해 가변적으로 결정되며 프레임 내의 활성화 블록구간 만을 축출하는데 사용된다. 또한 높은 재생 속도에 따른 피치 손상과 같은 품질 저하를 최소화하기 위하여, 임계필터링은 유, 무성음 구분 없이 상대적은 낮은 활성도를 갖는 블록들을 우선적으로 제거한다. 실험 결과, 제안 방식은 기존의 피치 축출을 사용하는 SOLA(Synchonized OverLap Add) 방식보다 높은 품질 갖는 재생속도 제어 솔루션을 제공함을 알 수가 있었다.