• 제목/요약/키워드: rejection

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Intelligent Tuning of PID Controller With Disturbance Rejection Using Bacterial Foraging

  • Kim, Dong-Hwa;Cho, Jae-Hoon
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2004년도 추계학술대회 학술발표 논문집 제14권 제2호
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    • pp.15-20
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    • 2004
  • In this paper, design approach of PID controller with rejection function against external disturbance in motor control system is proposed using bacterial foraging based optimal algorithm. Up to the present time, PID Controller has been used to operate for AC motor drive because of its implementational advantages in practice and simple structure. However, it is not easy to achieve an optimal PID gain with no experience, since the gain of the PID controller has to be manually tuned by trial and error in the industrial system with disturbance. To design disturbance rejection tuning, disturbance rejection conditions based on H$\_$$\infty$/ are illustrated and the performance of response based on the bacterial foraging is computed for the designed PID controller as ITSE (Integral of time weighted squared error). Hence, parameters of PID controller are selected by bacterial foraging based optimal algorithm to obtain the required response.

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음소기반 인식 네트워크에서의 단어 검출률을 이용한 문장거부 (Sentence Rejection using Word Spotting Ratio in the Phoneme-based Recognition Network)

  • 김형태;하진영
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 2005년도 춘계 학술대회 발표논문집
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    • pp.99-102
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    • 2005
  • Research efforts have been made for out-of-vocabulary word rejection to improve the confidence of speech recognition systems. However, little attention has been paid to non-recognition sentence rejection. According to the appearance of pronunciation correction systems using speech recognition technology, it is needed to reject non-recognition sentences to provide users with more accurate and robust results. In this paper, we introduce standard phoneme based sentence rejection system with no need of special filler models. Instead we used word spotting ratio to determine whether input sentences would be accepted or rejected. Experimental results show that we can achieve comparable performance using only standard phoneme based recognition network in terms of the average of FRR and FAR.

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Hypochlorite treatment of polyamide membrane for improved reverse osmosis performance

  • Shao, P.;Kurth, C.J.
    • Membrane and Water Treatment
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    • 제4권1호
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    • pp.69-81
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    • 2013
  • The pH-dependent inter-conversion of the three free chlorine species ($Cl_2$, HOCl, OCl-) present in the aqueous hypochlorite solution was theoretically investigated. Each species was found overwhelmingly present in a characteristic pH range. Hypochlorite treatment of the polyamide membrane was carried out over these pH ranges and various membrane responses were observed. As pH is less than 8, membrane tends to be N-chlorinated by $Cl_2$ and HOCl, and N-chlorinated membrane showed reduced water permeance and salt rejection. As pH rises to 10-12, $OCl^-$ appears to be the dominating chlorine species. Membrane hydrolysis was found to well interpret the improved water permeance and salt rejection. When the pH is between 8-10, both N-chlorination and hydrolysis contribute to the response of the membrane, and the treated membrane showed improved salt rejection but reduced water permeation. Excessive hydrolysis occurred while the membrane was treated at pH 13 for the much stronger alkalinity.

CDMA이동통신환경에서의 음성인식을 위한 왜곡음성신호 거부방법 (Distorted Speech Rejection For Automatic Speech Recognition under CDMA Wireless Communication)

  • 김남수;장준혁
    • 한국음향학회지
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    • 제23권8호
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    • pp.597-601
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    • 2004
  • 본 논문에서는 CDMA이동통신 환경에서의 음성인식을 위한 왜곡음성신호의 전처리-지부방법을 소개한다. 먼저, CDMA이동통신 채널에서의 왜곡된 음성신호를 분석하고 분석된 매커니즘을 바탕으로 채널에 의해 왜곡된 음성신호를 음성의 준주기성을 바탕으로 하여 거부하는 알고리즘을 제안한다. 실험을 통해 제안된 전처리-거부방법이 적은 계산량을 가지고 음성인식에 적용되어 효과적으로 CDMA에 환경에서 채널왜곡된 음성신호를 거부-할 수 있음을 알 수 있었다.

Progress in Transgenic Cloned Pig for Xenotransplantation

  • Park, Kwang-Wook
    • 한국수정란이식학회:학술대회논문집
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    • 한국수정란이식학회 2003년도 제3회 발생공학 국제심포지움 및 학술대회
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    • pp.9-19
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    • 2003
  • Pig organ is thought to be the most suitable nonhuman organ for xenotransplanstation. However, one of the major constraints to using pig organs for xenotransplantation is human natural antibody-mediated hyperacute rejection (HAR). Elimination of a(1,3) galactosyltransferase (GGTA1) from the pig is expected to be a solution to the problem of hyperacute rejection. ry1any efforts have made characterization of GGTA1 in structure and function. improvement in the technique of DNA transfection of somatic cells and advancement of the pig NT, a specific modification has been made to one copy of the GGTA1 gene by Missouri group in 2002. To date because homozygousity of the genetic modification has been achieved in this gene, the role of gala(1,3) gal specific natural antibody in HAR and the efficacy of xenotransplantation in a nonhuman primate model will be addressed. If other genes are found to be involved in rejection of pig donors by primates, the technology will be available to modify those genes so that rejection can be overcome.

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공격적 행동의 유형 및 성별에 따른 집단 괴롭힘 가해아동과 피해아동의 또래관계 비교 (Peer Rejection and Acceptance of Bullies and Victims: Differences in Gender and Types of Aggression)

  • 이은주
    • 아동학회지
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    • 제22권2호
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    • pp.167-180
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    • 2001
  • With 338 fifth-grade students as subjects, this study examined variations in the relation between school bullying and rejection or acceptance by peers as a function of gender and types of aggression. Results showed that the more a boy bullied other children, the more likely he was to be rejected by peers. The more a girl bullied other children, the more likely she was to be accepted by peers. Girls' aggressive behaviors also contributed to their acceptance by peers. When levels of physical and relational aggression were kept constant, verbal aggression was positively related to peer rejection for boys but negatively related for girls. The use of relational aggression contributed to peer rejection only for girls. The findings provide preliminary bases for understanding bullying. Implications of the gender differences are discussed.

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주기적인 외란 제거에 있어서 빠른 오프라인 학습 제어 접근 방식 (A Fast off-line Learning Control Approach to Rejection of Periodic Disturbances)

  • 하인중;장정국;박진원;권정훈
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.107-109
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    • 2007
  • The recently-developed off-line learning control approaches for the rejection of periodic disturbances utilize the specific property that the learning system tends to oscillate in steady state. Unfortunately, the prior works have not clarified how closely the learning system should approach the steady state to achieve the rejection of periodic disturbances to satisfactory level. In this paper, we address this issue extensively for the class of linear systems. We also attempt to remove the effect of other aperiodic disturbances on the rejection of the periodic disturbances effectively. In fact, the proposed learning control algorithm can provide very fast convergence performance in the presence of aperiodic disturbance. The effectiveness and practicality of our work is demonstrated through mathematical, performance analysis as well as various simulation results.

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Low Spurious Image Rejection Mixer for K-band Applications

  • Lee, Moon-Que;Ryu, Keun-Kwan;Kim, Hyeong-Seok
    • KIEE International Transactions on Electrophysics and Applications
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    • 제4C권6호
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    • pp.272-275
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    • 2004
  • A balanced single side-band (SSB) mixer employing a sub-harmonic configuration is designed for up and down conversions in K-band. The designed mixer uses anti-parallel diode (APD) pairs to effectively eliminate even harmonics of the local oscillator (LO) spurious signal. To reduce the odd harmonics of LO at the RF port, we employ a balanced configuration for LO. The fabricated chip shows 12$\pm$2dB of conversion loss and image-rejection ratio of about 20dB for down conversion at RF frequencies of 24-27.5GHz. As an up-conversion mode, the designed chip shows 12dB of conversion loss and image-rejection ratio of 20 ~ 25 dB at RF frequencies of 25 to 27GHz. The odd harmonics of the LO are measured below -37dBc.

신경 회로망과 관측기에 기반한 2-mass 시스템에서의 속도 제어기 설계 (Design of a Speed Controller for 2-Mass System Based on Neural Network and Observer)

  • 현대성;박정일
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.361-361
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    • 2000
  • In the 2-mass system with flexible shaft, a torsional vibration is often generated because of the elastic elements in torque transmission as the newly required speed response which is very close to the primary resonant frequency. This vibration makes it difficult to achieve quick responses of speed and disturbance rejection. In this paper, 2-mass system is designed by using pole placement based on optimal control theory fur fast speed response and torsional vibration elimination and using neural network for disturbance rejection in particular. The simulation results show that the proposed controller based on neural network and full state feedback controller has better performance than 려ll state feedback controller, especially fur disturbance rejection.

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Narrow Band Interference Suppression In Multiuser CDMA System By Linear Prediction In Subband

  • Yoon-Gi Yang
    • 인터넷정보학회논문지
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    • 제2권3호
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    • pp.27-36
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    • 2001
  • Recently much attention has been paid for interference mitigation technique for the COMA system, since more capacity is available with same bandwidth. In this paper, we introduces a novel adaptive interference suppression techniques for the CDMA system with narrow band interference. The proposed interference rejection scheme employs the adaptive linear prediction techniques in the subband. In each subband, we can more easily find and cancel the narrow band signal as compared to the full band. Thus, the proposed interference rejection can be classified as another time-frequency techniques for the narrow band interference rejection(10). Computer simulation is conducted for the 3-G COMA system with IF band sampling techniques, yielding better interference rejection and bit error rate performance as compared to conventional one. Also, optimum filter is analyzed and from the analysis, it can be shown the subband prediction techniques can suppress narrow band interference more efficiently.

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