• Title/Summary/Keyword: Bisection

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

  • Lee, Dong-Hyun;Hong, Sun-Ki
    • Proceedings of the KIEE Conference
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    • 2004.10a
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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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Stability of Cantilever-Type Columns under Nonconservative Load (비보존력이 작용하는 캔틸레버형 기둥의 안정성)

  • 오상진;이병구;최규문
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2002.10a
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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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A Study for NHPP software Reliability Growth Model based on polynomial hazard function (다항 위험함수에 근거한 NHPP 소프트웨어 신뢰성장모형에 관한 연구)

  • Kim, Hee Cheul
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.7 no.4
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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.

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

  • Jang, Gyeong-Ho;Jeong, Sun-Gi
    • Journal of KIISE:Computer Systems and Theory
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    • v.28 no.12
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    • pp.653-659
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    • 2001
  • In this paper, we propose an efficient algorithm for constructing cylindrical panoramic image. At first, we describe a fast image alignment algorithm, which matches image strips located on equal distance for image centers. And then, we explain how to estimate accurately the effective focal length of camera by a bisection method. Although there is a limitation in that the image should be taken by a camera with pure panning motion, the proposed simple and fast algorithm is applicable to practical application.

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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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    • v.38 no.5
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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.

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

  • 윤석준
    • Proceedings of the Korea Society for Simulation Conference
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    • 1999.04a
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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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A Study on the Drift-minimization in the Transistor Differential Amplifier (트란지스터 착동증폭기의 표동 극소화에 관한 연구)

  • 김종상
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.4 no.3
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    • pp.28-33
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    • 1967
  • The analysis of differential amplifier is simplified by the extention of bisection theorem. In order to reduce the thermal and porwor drifts, a self compensating circuit is employed. The optimum conditions of the self compensating circuit are: the base-emitter voltage of one transistor should be equal to the other's base-emitter voltage for basic self compensating circuit, the tempereature coefficients of base-emitter voltage of one transistor equal to the others for thermal compensation. By regarding the thermal and power drifts the experiments were performed were performed and the numerical results were consistent with the measured values.

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

  • 손동수;김일화;이동원;최창열;윤상보;류일선;서국현;이광원;유충원
    • Journal of Embryo Transfer
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    • v.9 no.1
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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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Scattering Analysis of Radar Target via Evolutionary Adaptive Wavelet Transform (진화적 적응 웨이브릿 변환에 의한 레이다 표적의 산란 해석)

  • Choi, In-Sik
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.3
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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.

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

  • Yeo, D.J.
    • Journal of Power System Engineering
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    • v.9 no.3
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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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