• 전력전자학회논문지
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• 제24권5호
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• pp.372-378
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• 2019

This study proposes a new zero-current-zero-voltage-transition (ZCZVT) boost-flyback converter using a soft switching auxiliary circuit. The proposed converter integrates the boost and flyback converters to increase the voltage with a low duty ratio. The main and auxiliary switches turn the ZCZVT conditions on and off. Thus, the proposed converter has high efficiency. The voltage gain at the steady state is derived, and the inductor volt-second balance and the design guidelines are presented. Finally, the performance of the proposed converter is validated by experimental results from a 200 W, 30 V DC input, 400 V DC output, and 200 kHz boost-flyback converter prototype.

• 호남수학학술지
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• 제34권4호
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• pp.571-584
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• 2012

In this study, we investigate the concept of zero-divisor graphs of multiplication modules over commutative rings as a natural generalization of zero-divisor graphs of commutative rings. In particular, we study the zero-divisor graphs of the module $\mathbb{Z}_n$ over the ring $\mathbb{Z}$ of integers, where $n$ is a positive integer greater than 1.

• Journal of the Korean Data and Information Science Society
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• 제14권2호
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• pp.177-186
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• 2003

The Zero-Inflated Poisson regression is a model for count data with exess zeros. When the correlated response variables are intrested, we have to extend the univariate zero-inflated regression model to multivariate model. In this paper, we study and simulate the multivariate zero-inflated regression model. A real example was applied to this model. Regression parameters are estimated by using MLE's. We also compare the fitness of multivariate zero-inflated Poisson regression model with the decision tree model.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.564-570
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• 2010

Last train of the vehicle for eht energy saving and improved performance PWM converters ares widely used. In the case of PWM converters by the zero detection system performance depends on whether it can be argued. Zero voltage detectio method of the hardware and software approach is to in this paper, the zero detection methods for hardware and software problems that have occured as a complemnetary technique was expained.

• Journal of applied mathematics & informatics
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• 제29권1_2호
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• pp.135-143
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• 2011

As a zero set of some multivariate splines, the piecewise algebraic variety is a kind of generalization of the classical algebraic variety. This paper presents an algorithm for isolating real roots of the zero-dimensional piecewise algebraic variety which is based on interval evaluation and the interval zeros of univariate interval polynomials in Bernstein form. An example is provided to show the proposed algorithm is effective.

• 대한수학회논문집
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• 제19권2호
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• pp.329-336
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• 2004

In this paper, we study relationships between zero characteristic properties and minimality of orbit closures or limit sets of points. Also, we characterize the set of points of zero characteristic properties. We show that the set of points of positive zero characteristic property in a compact spaces X is the intersection of negatively invariant open subsets of X.

• 대한수학회지
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• 제46권2호
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• pp.313-325
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• 2009

We consider zero-divisor graphs with respect to primal, nonprimal, weakly prime and weakly primal ideals of a commutative ring R with non-zero identity. We investigate the interplay between the ringtheoretic properties of R and the graph-theoretic properties of ${\Gamma}_I(R)$ for some ideal I of R. Also we show that the zero-divisor graph with respect to primal ideals commutes by localization.

• Kyungpook Mathematical Journal
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• 제51권1호
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• pp.37-42
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• 2011

Let M be an R-module and S a semigroup. Our goal is to discuss zero-divisors of the semigroup module M[S]. Particularly we show that if M is an R-module and S a commutative, cancellative and torsion-free monoid, then the R[S]-module M[S] has few zero-divisors of size n if and only if the R-module M has few zero-divisors of size n and Property (A).

• 한국수학사학회지
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• 제14권1호
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• pp.101-108
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• 2001

There are two uses of zero which are both important but are different. One use of zero is as a number itself. The number zero is an abstract concept measuring the size of set with no elements in it. The second use of it is as an empty place indicator in our place-value number system. It is the notation. In this paper, we study a history of zero and the mistakes from a few earlier works in connection with some arithmetical operations involving the number zero.

• Current Applied Physics
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• 제18권11호
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• pp.1275-1279
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• 2018

We investigate the change of the Fano effect by considering one Majorana zero mode to couple laterally to the single-dot Fano interferometer. It is found that the Majorana zero mode quenches the Fano effect thoroughly and causes the conductance to be independent of the dot level, the dot-lead coupling, and the increase of the Majorana-dot coupling. As a result, the linear conductance becomes only related to the interlead coupling and the magnetic-flux phase factor. These results can be helpful for the detection of Majorana zero mode.