• Journal of the Chungcheong Mathematical Society
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• v.19 no.1
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• pp.49-56
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• 2006

A convergence behavior is under investigation near a simple real zero for the k-fold pseudo-Olver's method defined by extending the classical Olver's method. The order of convergence is shown to be at least k+3. The asymptotic error constant is explicitly given in terms of k and the corresponding simple zero. Various numerical examples with a proposed zero-finding algorithm are successfully confirmed with the use of symbolic and computational ability of Mathematica.

• The Mathematical Education
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• v.46 no.4
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• pp.357-369
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• 2007

Teachers and students' knowledge of zero was investigated through data collected from 16 preservice secondary mathematics teachers and 20 gifted secondary school students. Results showed that these teachers and students had an inadequate knowledge about zero. They exhibited a reluctance to accept zero as an attribute for classification, confusion as to whether or not zero is a number, and stable patterns of computational error. Although leachers and researchers have long recognized the value of analyzing student errors for diagnosis and remediation, students have not been encouraged to take advantage of errors as learning opportunities in mathematics instruction. The article suggests using errors as springboards for inquiry in action, discusses its potential contributions to mathematics instruction by analyzing students and preservice teachers errors related to zero.

• Journal of the Chungcheong Mathematical Society
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• v.20 no.1
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• pp.11-21
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• 2007

Given a nonlinear function f : $\mathbb{R}{\rightarrow}\mathbb{R}$ that has a simple real zero ${\alpha}$, a new numerical method to be called k-fold pseudo- Halley's method is proposed and it's error analysis is under investigation to confirm the convergence behavior near ${\alpha}$. Under the assumption that f is sufficiently smooth in a small neighborhood of ${\alpha}$, the order of convergence is found to be at least k+3. In addition, the corresponding asymptotic error constant is explicitly expressed in terms of k, ${\alpha}$ and f as well as the derivatives of f. A zero-finding algorithm is written and has been successfully implemented for numerous examples with Mathematica.

• The KIPS Transactions:PartA
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• v.12A no.5 s.95
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• pp.391-394
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• 2005

In this paper, we study the average case error of the Trapezoidal rule using zero mean-Gaussian. Assume that we have n subintervals (for simplicity equal length) partitioning [0,1] and that each subinterval has the length h. Then, for $r{\leq}2$, we show that the average error between simple Trapezoidal rule and the composite Trapezoidal rule on two consecutive subintervals is bounded by $h^{2r+3}$ through direct computation of constants $c_r$.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.79-82
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• 2004

In this study, a new refinement technique for 3-dimensional hexahedral element mesh is proposed, which is aimed at the control of mesh density. With the proposed scheme the mesh is refined adaptively to the elemental error which is estimated by 'a posteriori' error estimator based on the energy norm. A desired accuracy of an analysis i.e. a limit of error defines the new desired mesh density map on the current mesh. To obtain the desired mesh density, the refinement procedure is repeated iteratively until no more elements to be refined exist. In the algorithm, at first the regions of mesh to be refined are defined and, then, the zero-thickness element layers are inserted into the interfaces between the regions. All the meshes in the regions, in which the zero-thickness layers are inserted, are to be regularized in order to improve the shape of the slender elements on the interfaces. This algorithm is tested on a simple shape of 2-d quadrilateral element mesh and 3-d hexahedral element mesh. A numerical example of elastic deformation of a plate with a hole shows the effectiveness of the proposed refinement scheme.

• Korean Architects
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• s.525
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• pp.22-23
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• 2013

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.1
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• pp.29-34
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• 2011

In this paper, we propose and analyze the equalizer schemes, zero-forcing (ZF) and minimum mean square error (MMSE) in power line communication (PLC) system for automatic meter reading (AMR). For efficient implementation of AMR system with PLC, effects of impulsive noise and multipath channel should be mitigated. To overcome these effects, the above equalizer schemes are employed. System performance is evaluated in term of bit error rate. From simulation results, it is confirmed that the equalizer can significantly improve bit error rate (BER) performance in PLC system, and MMSE equalizer provides better performance than ZF scheme. The results of this paper can be applied to AMR system as well as various smart grid services using PLC.

• The Transactions of the Korean Institute of Power Electronics
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• v.19 no.2
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• pp.184-193
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• 2014

This paper presents a high performance ZPE(zero-phase-error) speed controller for PMSM(permanent magnet synchronous motor) drives. A comparison study between conventional general purpose speed controller in modern industry fields such as PI, IP and 2-degree of freedom controller presented also. The proposed ZPE speed controller is found suitable for vector controlled PMSM drives in giving the high level of performance while maintaining the excellent response at the time of speed command changing. In MATLAB-based comparative simulation and experiment results with commercial drive system, the proposed method shows a superior control performance compared with the conventional speed controller widely-used.

• Communications for Statistical Applications and Methods
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• v.3 no.1
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• pp.243-255
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• 1996

The number of neutron signals from a neutral particle beam(NPB) at the detector, without any errors, obeys Poisson distribution, Under two assumptions that NPB scattering distribution and aiming errors have a circular Gaussian distribution respectively, an exact probability distribution of signals becomes a Poisson-power function distribution. In this paper, we show that the error rate in simple hypothesis testing for the limiting Poisson-power function distribution is not zero. That is, the limit of ${\alpha}+{\beta}$ is zero when Poisson parameter$\kappa\rightarro\infty$, but this limit is not zero (i.e., $\rho\ell$>0)for the Poisson-power function distribution. We also give optimal decision algorithms for a specified error rate.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.10
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• pp.1865-1870
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• 2015

In signal processing, the zero-error probability (ZEP) criterion and related algorithm (MZEP) outperforms MSE-based algorithms and yields superior and stable convergence in impulsive noise environment. In this paper, the analysis of the relationship with MSE criterion proves that ZEP criterion has equivalent optimum solution of MSE criterion. Also this work reveals that the magnitude controlled input of MZEP algorithm plays the role in keeping the optimum solution undisturbed from impulsive noise.