• 제목/요약/키워드: approximation technique

검색결과 562건 처리시간 0.031초

A Study of Designing of Multi-Carrier CDMA System with Multi- Detector based on DGT

  • Kong, Hyung-Yun;Ho, Kwang-Chun
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -2
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    • pp.1343-1345
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    • 2002
  • In this paper, we introduce the MC-CDMA (Multi-Carrier CDMA) system with MD (multi-detector). Due to unknown functional form of noise in wireless channel environments, it is not easy to design the detector through estimating the functional form of noise. Instead, we design the MD, which is constructed based on DGT (Data Grouping Technique) and quantiles estimated through RMSA (Robbins-Monro Stochastic Approximation) algorithm.

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AUXILIARY PRINCEPLE AND ERROR ESTIMATES FOR VARIATIONAL INEQUALITIES

  • NOOR, MUHAMMED ASLAM
    • 호남수학학술지
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    • 제15권1호
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    • pp.105-120
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    • 1993
  • The auxiliary principle technique is used to prove the uniqueness and the existence of solutions for a class of nonlinear variational inequalities and suggest an innovative iterative algorithm for computing the approximate solution of variational inequalities. Error estimates for the finite element approximation of the solution of variational inequalities are derived, which refine the previous known results. An example is given to illustrate the applications of the results obtained. Several special cases are considered and studied.

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견인 어레이 형상 추정의 칼만 필터 접근 방법에 대한 성능 개선 (The Performance Improvement of Towed Array Shape Estimation Using Kalman Filters)

  • 박민수;도경철;오원천;윤대희;이충용
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.691-694
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    • 1999
  • This paper presents a performance improvement technique of 2-D towed array shape estimation using Kalman filters. The proposed algorithm by linear model approximation corrects the position errors caused by the Kalman filter results. However, since the assumed linear model makes errors at bending parts, the spline interpolation algorithm based on curve is proposed to reduce the errors.

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DNA Coding Method에 기반한 신경회로망 진화 기법 (Neural Network Evolution based on DNA Coding Method)

  • 이원희;강훈
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.456-459
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    • 1999
  • In this paper, we propose a new neural network based on the DNA coding method. The initial population of the structure information and the weights for the neural network is generated, and then the descendants are chose with the Elitist selection by the genetic algorithm. The evolutionary technique and the suitable fitness measure are used to find a neural network with the fractal number of layers. which represents a good approximation to the given function.

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항공기 및 미사일용 레이돔 설계에 관한 연구 (A Design Study of Radomes for Airplanes and Missiles)

  • 나형기;박창현
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.139-142
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    • 1999
  • In this paper, a method of Radome design is considered. The shape is similar to tangent-ogive, and the antenna is a waveguide broad-wall slot array antenna. The characteristic of the Radome material is obtained by measuring test samples. By analyzing the transmission efficiency of the flat plate, Radome wall thickness is determined firstly. And then, the detailed characteristics of the Radome are analyzed by using GO-PO approximation technique. Several simple parameters of the designed Radome are tested and compared with the simulation results.

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Formulation for the Relativistic Blast Waves and GRB Afterglows

  • 엄정휘
    • 천문학회보
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    • 제35권1호
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    • pp.81.1-81.1
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    • 2010
  • We present a detailed description of the blast-wave modeling technique for a very general class of GRB explosions. Providing a simple method of evaluating the blast energy, we demonstrate that a common approximation of pressure balance for the blast wave violates the energy-conservation law significantly for adiabatic blast waves. We show that the energy-violation problem is successfully resolved by the "mechanical model" that we developed. GRB afterglow lightcurves that are produced by the forward and reverse shock waves of the blast wave are presented.

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WAVENET을 이용한 비선형 시스템의 제어 (Control of Nonlinear System using WAVENET)

  • 박두환;김경엽;이준탁
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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    • pp.257-261
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    • 2005
  • The helicopter system is non-linear and complex. Futhermore, because of absence of accurate mathematical model, it is difficult accurately to control its attitude. therefore, we propose a WAVENET control technique to control efficiently its elevation angle and azimuth one. Wavelet neural network(WAVENET) can construct systematically initial neural network as applying wavelet theory to feedforward network. It is proved through computer simulation that WAVENET has more excellent approximation capability than existing neural network. The simulation results using MATLAB are introduced.

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Legendre Tau Method for the 2-D Stokes Problem

  • Jun, SeRan;Kang, Sungkwon;Kwon, YongHoon
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제4권2호
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    • pp.111-133
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    • 2000
  • A Legendre spectral tau approximation scheme for solving the two-dimensional stationary incompressible Stokes equations is considered. Based on the vorticity-stream function formulation and variational forms, boundary value and normal derivative of vorticity are computed. A factorization technique for matrix stems based on the Schur decomposition is derived. Several numerical experiments are performed.

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웨이브렛과 유전 알고리즘을 이용한 시스템 근사화 (The Study of Wavelet Theory for System Identifications)

  • 이영석;김동옥;서보혁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 B
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    • pp.638-640
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    • 1998
  • This paper discusses approximation modelling of discrete-time linear time-varying system(LTVS). The wavelet theory and genetic algorithm are considered as a tool for representing and approximating a LTVS. The joint time-frequency properties of wave analysis are appropriate for describing the LTVS. Simulation results is included to illustrate the potential application of the technique.

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광대역통신망의 링크용량 설계 모형 및 알고리듬 (Model and Algorithm for Link Dimensioning of B-ISDN)

  • 주종혁
    • 산업경영시스템학회지
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    • 제22권51호
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    • pp.99-108
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    • 1999
  • B-ISDN link dimensioning is often known as a difficult problem because of the characteristics of Asynchronous Transfer Mode(ATM) such as various Quality of Services of different service requirements, and the statistical multiplexing resulting from virtual path/virtual circuit connections. In this paper, we propose a nonlinear integer optimization model for dimensioning B-ISDN considering the statistical multiplexing effects of virtual path connections(VPCs) and the modularity of resources allocated to a transmission link. The algorithm based on the simultaneous linear approximation technique as well as some numerical results will be also presented.

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