• 제목/요약/키워드: bisection

검색결과 157건 처리시간 0.023초

데이터 분석 알고리즘을 이용한 철손 측정 (A study on Iron Loss Measurement in Electric Machines)

  • 이동현;홍선기
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.49-51
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    • 2004
  • The iron loss in electric machines takes large part of machine losses and the reduction of iron loss brings the increase of the efficiency. In the rotating machines, however it is very difficult to calculate the iron loss and to get the exact experiment result because the measuring precesses are very complex and laborious. As is well known, the relation between the flux density B and the magnetic field intensity H relation is not linear. For the iron loss, B and H must be measured and usually B becomes the reference wave(sine wave) and the following H is measured using H-coil. To make the B as sine wave, B is controlled by some devices. The error is controlled to become zero by the proposed algorithm which uses the bisection algorithm. The experiments are compared with the simulation results, and they show acceptable agreements.

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비보존력이 작용하는 캔틸레버형 기둥의 안정성 (Stability of Cantilever-Type Columns under Nonconservative Load)

  • 오상진;이병구;최규문
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2002년도 가을 학술발표회 논문집
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    • pp.244-251
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    • 2002
  • The purpose of this paper is to investigate the stability of tapered columns with general boundary condition(translational and rotational elastic support) at one end and carrying a tip mass of rotatory inertia with translational elastic support at the other end. The column model is based on the classical Bernoulli-Euler beam theory which neglects the effects of rotatory inertia and shear deformation. The governing differential equation for the free vibrations of linearly tapered columns subjected to a subtangential follower force is solved numerically using the corresponding boundary conditions. And the bisection method is used to calculate the critical divergence/flutter load. After having verified the results of the present study, the frequency and critical divergence/flutter load are presented as functions of various nondimensional system parameters.

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다항 위험함수에 근거한 NHPP 소프트웨어 신뢰성장모형에 관한 연구 (A Study for NHPP software Reliability Growth Model based on polynomial hazard function)

  • 김희철
    • 디지털산업정보학회논문지
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    • 제7권4호
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    • pp.7-14
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    • 2011
  • Infinite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rate per fault (hazard function). This infinite non-homogeneous Poisson process is model which reflects the possibility of introducing new faults when correcting or modifying the software. In this paper, polynomial hazard function have been proposed, which can efficiency application for software reliability. Algorithm for estimating the parameters used to maximum likelihood estimator and bisection method. Model selection based on mean square error and the coefficient of determination for the sake of efficient model were employed. In numerical example, log power time model of the existing model in this area and the polynomial hazard function model were compared using failure interval time. Because polynomial hazard function model is more efficient in terms of reliability, polynomial hazard function model as an alternative to the existing model also were able to confirm that can use in this area.

이동운동모델만을 이용한 수평 회전 카메라로부터 실린더 파노라믹 영상 생성 (Constructing Cylindrical Panoramic Image from Panning Motion Camera using Simple Translation Motion Model)

  • 장경호;정순기
    • 한국정보과학회논문지:시스템및이론
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    • 제28권12호
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    • pp.653-659
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    • 2001
  • 본 논문에서는 실린더 파노라믹 영상을 생성하기 위한 효율적인 알고리즘을 제시한다. 먼저 영상 정렬 시 실린더와 영상간의 관계를 이용한 영상의 중심으로부터 같은 거리에 있는 영상 스트립을 비교하는 효율적인 영상 정렬 알고리즘을 기술하고, 원과 원에 접하는 다각형간의 관계를 이용하여 이분법으로부터 초점거리를 정확하게 추정하는 방법을 설명한다. 본논문에서 제안하는 알고리즘은 카메라 운동에 대한 제약점은 있지만, 빠르고 간단하기 때문에 실제 응용에서 효과적으로 사용 가능하다.

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Cooperative Decode-and-Forward Relaying for Secure Multicasting

  • Lee, Jong-Ho;Sohn, Illsoo;Song, Sungju;Kim, Yong-Hwa
    • ETRI Journal
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    • 제38권5호
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    • pp.934-940
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    • 2016
  • In this paper, secure multicasting with the help of cooperative decode-and-forward relays is considered for the case in which a source securely sends a common message to multiple destinations in the presence of a single eavesdropper. We show that the secrecy rate maximization problem in the secure multicasting scenario under an overall power constraint can be solved using semidefinite programing with semidefinite relaxation and a bisection technique. Further, a suboptimal approach using zero-forcing beamforming and linear programming based power allocation is also proposed. Numerical results illustrate the secrecy rates achieved by the proposed schemes under secure multicasting scenarios.

실시간 시뮬레이션을 위한 최적 검색 기법 연구 (A Study n Real-time Searching Algorithms)

  • 윤석준
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 1999년도 춘계학술대회 논문집
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    • pp.204-211
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    • 1999
  • 항공기, 자동차, 전차 등 차량의 시스템 또는 운동의 시뮬레이션에서는 다양한 종류의 불연속적인 파라미터 값들이 데이터 테이블의 형태로 주어지게 되는데, 본 연구에서의 관심은 적분 스텝의 크기가 고정되는 일반적인 실시간 시뮬레이션의 제약 하에서 기존의 검색 기법들을 비교하고, 최적의 검색 기법을 개발하는 것이다. 본 연구에서는 전통적으로 수치해석, 시뮬레이션, 데이터베이스 등 다양한 학문 및 응용기술 분야에서 개발된 데이터 검색 기법들을 조사하여 비교하였다. 또한, 다양한 크기와 형태의 데이터 테이블들을 사용하여 수치비교시험을 수행하였는데, 그 경향은 이론에 근거한 예상과 대체로 일치하였다. 한편, 검색하고자 하는 파라미터 값이 임의의 dynamics를 갖고 변한다면, 이러한 정보를 이용하여 주어진 데이터 테이블 내의 검색 영역을 축소 시켜 검색속도를 향상시킬 수가 있다. 다양한 수치시험에서 이분 검색법(bisection method)은 축소된 테이블의 크기에만 영향을 받지만 보간 검색법(interpolation method)과 그 변형 기법들은 검색 대상 테이블들의 축소로 데이터의 형태가 직선형이 되는 효과를 얻기 때문에 검색속도를 단축시키는데 매우 탁월한 효과를 나타내었다. 결론적으로 dynamic-window 개념을 도입한 보간 검색법과 그 변형들이 이론적으로도 실험적으로도 최적의 검색속도를 보장함이 입증되었다.

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트란지스터 착동증폭기의 표동 극소화에 관한 연구 (A Study on the Drift-minimization in the Transistor Differential Amplifier)

  • 김종상
    • 대한전자공학회논문지
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    • 제4권3호
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    • pp.28-33
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    • 1967
  • 트란지스터 착동증폭기의 해석은 이등분 정리의 응용으로 간단히 되며 온도 및 전원전압의 변화에 의한 drfit는 자체보상회로에 의해서 감소시킬수 있다. 베스-에미터전압을 같게하는 기본자체보상회로와 이 전압의 온도계수를 같게 하는 온도자체보상회로를 써서 실험하여 양호한 결과를 얻었으며 이 회로의 조절은 이론치와 잘 일치함을 확인하였다.

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수정란 분할에 의한 한우 쌍태의 임신 (Pregnancy of Monozygotic Twins by Bisection of Korean Native Cattle Embryos)

  • 손동수;김일화;이동원;최창열;윤상보;류일선;서국현;이광원;유충원
    • 한국수정란이식학회지
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    • 제9권1호
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    • pp.43-48
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    • 1994
  • This study was carried out to produce monozygotic twin calves by transfer of bisected embryos. Four Korean native cattle donors were superovulated with FSH and flushed to collect embryos on day 6 or 7 of the estrus cycle. Morula and early blastocyst embryos showed 1 or 2 grade were bisected with microblade and each set of demi-embryos without zona pellucida were transferred nonsurgically to 10 recipients respectively. The results obtained were as follows; 1. Twenty four demi-embryos (92.3%) were separated from 13 original embryos and among them 20 demi-embryos (83.3%) had normal appearance without severe damage. 2. Four sets of fresh demi-embryos were transferred to 4 recipients and one recipient was twin pregnant 3. Six sets of frozen-thawed demi-embryos were transferred to 6 recipients. Two recipients were pregnant, one of them twin.

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진화적 적응 웨이브릿 변환에 의한 레이다 표적의 산란 해석 (Scattering Analysis of Radar Target via Evolutionary Adaptive Wavelet Transform)

  • 최인식
    • 한국군사과학기술학회지
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    • 제10권3호
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    • pp.148-153
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    • 2007
  • In this paper, the evolutionary adaptive wavelet transform(EAWT) is applied to the scattering analysis of radar target. EAWT algorithm uses evolutionary programming for the time-frequency parameter extraction instead of FFT and the bisection search method used in the conventional adaptive wavelet transform(AWT). Therefore, the EAWT has a better performance than the conventional AWT. In the simulation using wire target(Airbus-like), the comparisons with the conventional AWT are presented to show the superiority of the EAWT algorithm in the analysis of scattering phenomenology. The EAWT can be effectively applied to the radar target recognition.

끝이 잘린 원추형 셸의 진동해석 알고리즘의 개발 (Development of Vibrational Analysis Algorithm for Truncated Conical Shells)

  • 여동준
    • 동력기계공학회지
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    • 제9권3호
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    • pp.58-65
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    • 2005
  • This paper deals with the free vibrations of truncated conical shell with uniform thickness by the transfer influence coefficient method. The classical thin shell theory based upon the $Fl\ddot{u}gge$ theory is assumed and the governing equations of a conical shell are written as a coupled set of first order differential equations using the transfer matrix. The Runge-Kutta-Gill integration and bisection method are used to solve the governing differential equations and to compute the eigenvalues respectively. The natural frequencies and corresponding mode shapes are calculated numerically for the truncated conical shell with any combination of boundary conditions at the edges. And all boundary conditions and the intermediate supports between conical shell and foundation could be treated only by adequately varying the values of the spring constants. Numerical results are compared with existing exact and numerical solutions of other methods.

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