• 제목/요약/키워드: rate of convergence

검색결과 3,458건 처리시간 0.034초

THE EFFECT OF QUADRATURE ERRORS IN PRACTICE

  • Kim, Chang-Geun
    • Korean Journal of Mathematics
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    • 제6권2호
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    • pp.195-203
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    • 1998
  • In [3], we showed that overintegration may be needed to obtain the optimal $H^1$ error rate for the $p$ version. In this paper, we examine the convergence of the $p$ version in practice, and comment on the implementation of the $p$ version in commercial codes. Also, we give an example of a problem with extremely rough coefficients, for which overintegration is necessary to obtain the optimal $H^1$ convergence rate.

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ON THE EXPONENTIAL INEQUALITY FOR NEGATIVE DEPENDENT SEQUENCE

  • Kim, Tae-Sung;Kim, Hyun-Chull
    • 대한수학회논문집
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    • 제22권2호
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    • pp.315-321
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    • 2007
  • We show an exponential inequality for negatively associated and strictly stationary random variables replacing an uniform boundedness assumption by the existence of Laplace transforms. To obtain this result we use a truncation technique together with a block decomposition of the sums. We also identify a convergence rate for the strong law of large number.

선형시스템을 위한 개선된 수렴속도를 갖는 기준모델 적응제어 (Model Reference Adaptive Control for Linear System with Improved Convergence Rate-parameter Adaptation Method)

  • Lim, Kye-Young
    • 대한전기학회논문지
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    • 제37권12호
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    • pp.884-893
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    • 1988
  • Adaptive controllers for linear unknown coefficient system, that is corrupted by disturbance, are designed by parameter adaptation model reference adaptive control(MRAC). This design is stemmed from the Lyapunov direct method. To reduce the model following error and to improve the convergence rate of the design, an indirect-suboptimal control law is derived. Proper compensation for the effects of time-varying coefficients and plant disturbance are suggested. In the design procedure no complete identification of unknown coefficients are required.

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융합 공학교육을 위한 마이크로 디그리 도입 (Micro Degree for Convergence Engineering Education)

  • 홍연기
    • 융복합기술연구소 논문집
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    • 제10권1호
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    • pp.31-36
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    • 2020
  • The purpose of this study is to discuss how to introduce micro degree for innovation in convergence education in our university. To this end, the background of the introduction of micro and nano degrees and domestic and foreign applications were reviewed. The reason why the rate of students completing the multi-degree was low was that the credits required for graduation were higher than that of other domestic universities, and the difficulty of the courses offered in the convergence major did not match the students. In order to reduce the burden of students learning convergence subjects while acquiring new knowledge and skills, the introduction of a micro degree is considered to be an alternative to the current convergence education.

Design of AT-DMB Baseband Receiver SoC

  • Lee, Joo-Hyun;Kim, Hyuk;Kim, Jin-Kyu;Koo, Bon-Tae;Eum, Nak-Woong;Lee, Hyuck-Jae
    • ETRI Journal
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    • 제31권6호
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    • pp.795-802
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    • 2009
  • This paper presents the design of an advanced terrestrial digital multimedia broadcasting (AT-DMB) baseband receiver SoC. The AT-DMB baseband is incorporated into a hierarchical modulation scheme consisting of high priority (HP) and low priority (LP) stream decoders. The advantages of the hierarchical modulation scheme are backward compatibility and an enhanced data rate. The structure of the HP stream is the same as that of the conventional T-DMB system; therefore, a conventional T-DMB service is possible by decoding multimedia data in an HP stream. An enhanced data rate can be achieved by using both HP and LP streams. In this paper, we also discuss a time deinterleaver that can deinterleave data for a time duration of 384 ms or 768 ms. The interleaving time duration is chosen using the LP symbol mapping scheme. Furthermore, instead of a Viterbi decoder, a turbo decoder is adopted as an inner error correction system to mitigate the performance degradation due to a smaller symbol distance in a hierarchically modulated LP symbol. The AT-DMB baseband receiver SoC is fabricated using 0.13 ${\mu}m$ technology and shows successful operation with a 50 mW power dissipation.

데이터 재활용 방식을 적용한 부호 알고리듬 (A Da7a-Recycling Sign Algorithm for Adaptive Equalization)

  • 김남용
    • 한국전자파학회논문지
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    • 제13권2호
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    • pp.130-135
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    • 2002
  • 이 논문에서 는 부호 알고리듬(Sign Algorithm)의 수렴성능을 향상시킨 새로운 Equalizer 알고리듬을 소개하였다. 이것은 입력 데이터를 재활용하여 필터계수를 다중 갱신하는 Data-Recycling 방식을 곱셈 계산이 적은 Sign 알고리듬에 적용하였다. Sign 알고리듬은 계산량이 적고 구현이 간단한 장점을 가지나 느린 수렴속도의 한계를 가지고 있다. 제안한 알고리듬은 Sign 알고리듬의 계산량이 적은 장점과 Data-Recycling LMS 알고리듬의 단순성과 빠른 수렴속도를 가지는 장점을 결합한 구조의 알고리듬이다. 컴퓨터 시뮬레이션에서 제안된 적응 등화 알고리듬은 LMS 알고리듬보다 2배 빠른 수렴 속도를 나타내었으며, 근사한 수렴성능에 조건에서 Data-Recycling LMS와 비교할 때 반으로 줄어든 곱셈 계산량을 보였다.

국가대표 여자 유도선수들의 스포츠 손상과 심박변이도와의 스포츠 융합 분석 (Sports convergence Analysis of Sports injuries and Heart Rate Variability in National Female Judo Athletes)

  • 김현철;박기준
    • 한국융합학회논문지
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    • 제11권4호
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    • pp.49-54
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    • 2020
  • 국가대표 여자 유도선수를 대상으로 스포츠 손상 발생률과 심박변이도 간의 상관관계를 알아보고자 하였다. 연구 참여자들은 자율신경 진단기(SA-6000)를 사용하여 심박변이도를 측정하였다. 평균 손상 발생률을 기준으로 스포츠 손상 발생률의 상위그룹과 하위그룹으로 분류하였으며, 두 그룹 간의 심박변이도를 알아보기 위해 독립표본 T-test와 스포츠 손상 발생 횟수와 심박변이도의 상관관계를 알아보기 위해 Pearson의 적률상관관계를 시행하였다. 심박변이도는 총 파워와 저주파에서 유의한 차이가 있었으며, 스포츠 손상 발생 횟수에 따른 심박변이도의 상관관계 분석에서도 총 파워와 저주파에서 유의한 차이가 있었다. 이러한 자료들은 향후 선수들의 스포츠 손상 예방프로그램을 만드는데 유용한 기초자료로 제공될 것으로 사료된다.

스크랩 장입 비율에 따른 다이캐스팅용 알루미늄 합금의 부식 특성 (Corrosion Characteristics of Aluminum Die Casting Alloys with Different Scrap Charge Rate)

  • 김준호;이승효
    • 한국표면공학회지
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    • 제53권6호
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    • pp.322-329
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    • 2020
  • The utilization of aluminum scrap is a subject of great importance in terms of reducing energy consumption and environmental protection. However, aluminum scrap contains impurities, which can degrade the properties of aluminum alloy, especially corrosion resistance. This study examines the effect of scrap charge rate of aluminum alloys about microstructures and corrosion characteristics. According to the metallographic examinations, Mg2Si tended to become coarser and its uniformity was decreased by increasing aluminum scrap charge rate. The immersion test exhibited corrosion progressed through the eutectic areas due to micro-galvanic interactions. Electrochemical measurements revealed that excess aluminum scrap could reduce the intergranular corrosion resistance of aluminum alloys. Results showed that the scrap charge rate is important factor in the design of corrosion resistance of aluminum die casting alloys.

교통시설개선을 위한 위험도 도출에 관한 연구 (The Study of Danger Rate for Improvement of Traffic Facilities)

  • 손진현
    • 한국산업융합학회 논문집
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    • 제9권4호
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    • pp.285-291
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    • 2006
  • A traffic accident is occurred by unbalance of reciprocal action of driver, vehicle and road conditions. To prevent the traffic accident, rapid and perfect road improvement is needed. But most of road improvement plans have insufficient budget. So decision maker has to determine the priority to invest. A model in this study, analyzing the effect of road conditions to the traffic accident, helps to decide the priority in road improvement. This study considered five danger indices ; 1) traffic volume, 2) speed variance, 3) vehicle mixing rate, 4) curved line radius, and 5) difference between design speed and running speed. Danger rate composed by five indices can be a scale of priority of improvement. The model in this study didn't consider all of factors about traffic accident. But this study can propose the methodology for traffic safety policy. For deriving the model, this study used data from highways in Korea and United States. Therefore the model has to apply the highways only.

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A Study on Face Recognition and Reliability Improvement Using Classification Analysis Technique

  • Kim, Seung-Jae
    • International journal of advanced smart convergence
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    • 제9권4호
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    • pp.192-197
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    • 2020
  • In this study, we try to find ways to recognize face recognition more stably and to improve the effectiveness and reliability of face recognition. In order to improve the face recognition rate, a lot of data must be used, but that does not necessarily mean that the recognition rate is improved. Another criterion for improving the recognition rate can be seen that the top/bottom of the recognition rate is determined depending on how accurately or precisely the degree of classification of the data to be used is made. There are various methods for classification analysis, but in this study, classification analysis is performed using a support vector machine (SVM). In this study, feature information is extracted using a normalized image with rotation information, and then projected onto the eigenspace to investigate the relationship between the feature values through the classification analysis of SVM. Verification through classification analysis can improve the effectiveness and reliability of various recognition fields such as object recognition as well as face recognition, and will be of great help in improving recognition rates.