• Journal of the Korean Mathematical Society
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• v.51 no.6
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• pp.1177-1187
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• 2014

In the current paper we study absolutely pure representations of quivers. Then over some nice quivers including linear quivers some sufficient conditions guaranteeing a representation to be absolutely pure is characterized. Furthermore some relations between atness and absolute purity is investigated. Finally it is shown that the absolutely pure covering of representations of linear quivers (including $A^-_{\infty}$, $A^+_{\infty}$ and $A^{\infty}_{\infty}$) by R-modules whenever R is a coherent ring exists.

• Bulletin of the Korean Mathematical Society
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• v.57 no.3
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• pp.781-802
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• 2020

For a fixed semi-Wakamatsu-tilting module _AT, we generalize the concepts of Auslander class, Bass class, and investigate many homological properties of such classes. Moreover, we establish an equivalence between the class of ∞-T-cotorsionfree modules and a subclass of the class of T-adstatic modules. Finally, a similar version of Auslander-Bridger approximation theorem and a nice property of relative cotranspose are obtained.

• Korean Management Science Review
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• v.26 no.1
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• pp.1-5
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• 2009

I study a solution concept which preserves the nice Nash equilibrium properties of two-person zero-sum games, and define a locally competitive equilibrium which is characterized by a saddle point with respect to the coordinates of strategies. I show that a locally competitive equilibrium shares the properties of uniqueness of equilibrium payoffs, interchangeablity of equilibrium strategies and convexity of the equilibrium set.

• Management Science and Financial Engineering
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• v.20 no.2
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• pp.1-5
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• 2014

The robust inventory control problem was proposed and solved by Bertsimas and Thiele (2006). Their results are very interesting in that the problem can be solved easily and also the solution possesses nice properties of those found in the traditional stochastic inventory control problem. However, their formulation is shown to be incorrect, which invalidates all of the results given there. In this paper, we propose an alternative formulation of the problem which uses a different but practically applicable uncertainty set. Under the newly proposed model, all of the useful properties given in Bertsimas and Thiele (2006) will be shown to be valid.

• Communications for Statistical Applications and Methods
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• v.3 no.1
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• pp.155-168
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• 1996

In this paper we consider the multiprocess dynamic normal model with parameters having a time dependent non-linear structure. We develop and study the recursive estimation procedure for the proposed model with normality assumption. It turns out thst the proposed model has nice properties such as insensitivity to outliers and quick reaction to abrupt changes of pattern.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10b
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• pp.532-534
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• 2001

Code and object reuse is big concern for fast and efficient Virtual Reality (VR) system development. Many VR packages offer reasonably nice abstractions for various functionalities. That is, software reuse at the functional level is well practiced. Many geometry models are rarely used for main \"characters\" but mostly for incidental and decorative objects. This is because the main \"character\" objects usually exhibit certain behavior incompatible with the way the geometric model is organized. Kim has made a clear distinction between form, function and behavior[1]. This naturally lends to a reuse method at the level form, function and behavior.nction and behavior.

• East Asian mathematical journal
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• v.26 no.4
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• pp.487-507
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• 2010

We study mathematization of natural thinking and some materials developed in geometric construction of regular n-polygons. This mathematization provides a nice model for illustrating interesting approaches to trigonometric functions and trigonometric ratios as well as their inter-connections. Thereby, results of this paper will provide the procedure of the development for these concepts in natural way, which will be helpful for understanding background knowledges.

• Journal of Integrative Natural Science
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• v.5 no.2
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• pp.131-134
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• 2012

Bae and Kim displayed a sequence of 4th degree self-reciprocal polynomials whose maximal zeros are related in a very nice and far from obvious way. Kim showed that the auxiliary polynomials in their results are related to Chebyshev polynomials. In this paper, we study two sequences of polynomials satisfying the recurrence of the auxiliary polynomials with generalized initial conditions. We obtain same results with the auxiliary polynomials from a sequence, and some interesting conjectural properties about resultants and discriminants from another sequence.

• Kyungpook Mathematical Journal
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• v.58 no.3
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• pp.495-505
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• 2018

The purpose of the present paper is to investigate Confluent hypergeometric distribution. We obtain some basic properties of this distribution. It is worthy to note that the Poisson distribution is a particular case of this distribution. Finally, we give a nice application of this distribution on certain classes of univalent functions of the conic regions.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.369-383
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• 2007

This paper is devoted to the foldness theory of implicative ideals in BCK-algebras. We use the fuzzy point concept to give some characterizations of fuzzy n-fold implicative ideals and establish some relationships with various n-fold ideals. We also construct some algorithms for studying the foldness of implicative ideals in BCK-algebras.