• 충청수학회지
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• 제25권3호
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• pp.401-413
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• 2012

In the present paper we construct and introduce a new topology from an old one which are independent each of the other. The members of this topology are called ${\omega}_{\delta}$-open sets. We investigate some basic properties and their relationships with some other types of sets. Furthermore, a new characterization of regular and semi-regular spaces are obtained. Also, we introduce and study some new types of continuity, and we obtain decompositions of some types of continuity.

• 대한수학회보
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• 제51권3호
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• pp.641-651
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• 2014

Because of difficulty of using Schauder's fixed point theorem to the polynomial-like iterative equation, a lots of work are contributed to the existence of solutions for the polynomial-like iterative equation on compact set. In this paper, by applying the Schauder-Tychonoff fixed point theorem we discuss monotone solutions and convex solutions of the polynomial-like iterative equation on an open set (possibly unbounded) in $\mathbb{R}^N$. More concretely, by considering a partial order in $\mathbb{R}^N$ defined by an order cone, we prove the existence of increasing and decreasing solutions of the polynomial-like iterative equation on an open set and further obtain the conditions under which the solutions are convex in the order.

• 대한전자공학회논문지SD
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• 제46권1호
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• pp.68-75
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• 2009

최근 마이크로프로세서의 성능이 빠르게 향상됨에 따라 주 메모리의 접근 시간이 증가하고 있어 캐쉬의 필요성이 증대되고 있다. 직접사상 캐쉬는 주 메모리의 각각의 블록이 하나의 캐쉬 라인에 사상되는 구조로서 사상되는 규칙이 간단하지만 서로 다른 블록이 하나의 캐쉬 라인에 사상될 경우 블록의 충돌에 의한 접근 실패율이 집합연관 캐쉬에 비해 높아진다. 본 논문에서는 OpenRISC 코어의 직접사상의 단점을 개선하기 위해 사원 집합연관 캐쉬 구조를 제시한다. 제시한 캐쉬는 주 메모리의 네 개의 블록이 하나의 캐쉬 라인에 사상되는 구조로서 직접사상 캐쉬에 비해 접근 실패율이 감소한다. 또한 라인 교체 방식으로 Pseudo-LRU 방식을 채택하여 LRU 정보를 저장하는 비트 수를 감소시켰다. FPGA 에뮬레이션을 이용하여 사원 집합연관 캐쉬를 포함한 OpenRISC 코어를 검증하였고, 테스트 프로그램을 이용하여 성능을 측정한 결과, 사원 집합연관 캐쉬를 포함한 OpenRISC 코어의 성능이 기존의 OpenRISC 코어의 성능에 비해 약 50% 향상되었고, 미스율은 15%이상 감소하였다.

• 대한수학회보
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• 제45권4호
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• pp.749-755
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• 2008

In this paper, we introduce the relatively new notion of fuzzy ${\omega}^O$-open set. We prove that the collection of all fuzzy ${\omega}^O$-open subsets of a fuzzy topological space forms a fuzzy topology that is finer than the original one. Several characterizations and properties of this class are also given as well as connections to other well-known "fuzzy generalized open" subsets.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제10권3호
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• pp.200-202
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• 2010

In this paper, we introduce the concept of fuzzy ${\gamma}$-quasi open sets which are generalizations of fuzzy ${\gamma}$-open sets, and obtain some basic properties of such fuzzy sets. Also we introduce and study the concepts of fuzzy ${\gamma}$-quasi continuous mapping and fuzzy ${\gamma}$-quasi open(closed) mapping.

• 대한수학회논문집
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• 제26권2호
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• pp.297-304
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• 2011

In this paper, we introduce closure operators [${\cdot}$]c and [${\cdot}$]a on a space and study some relations among [${\cdot}$]c, [${\cdot}$]a and countable tightness. We introduce the concepts of a strongly sequentially closed set and a strongly sequentially open set and show that a space X has countable tightness if and only if every strongly sequentially closed set is closed if and only if every strongly sequentially open set is open. Finally we find a generalization of the weak Fr$\'{e}$chet-Urysohn property which is equivalent to countable tightness.

• 한국지능시스템학회논문지
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• 제11권2호
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• pp.184-189
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• 2001

First, we find the characterization of fg-closure of a fuzzy set. Second, we study some properties of frg-closeds and fg-continuous mappings. Finaly, we introduce the concept of a fuzzy approximately continuous mapping and study its properties.

• 대한건축학회논문집:계획계
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• 제34권1호
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• pp.63-70
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• 2018

The foreign concession of Yokohama was the first downtown formed through the open port of Yokohama. It became a stepping stone to the center of the market economy. Yokohama was regarded as the turning point of modernization in Japanese history and it reached the high light of modern city in Japan. In the nineteenth century the term "open port" which occurred in East Asia was directly connected with modernization. Nevertheless, there is not many researches on architectural history about the central space of the open port city. As the method of research, we examine the parcels and spatial changes that are based on the contents of maps and pictures in terms of architectural history. For the foreign concession that was set up in Yokohama and the first open port in Japan, the spatial scope was set for certain and the temporal range was also set from the setting of the concession in 1859 to the abolition in 1899. The purpose of this study is to consider the future research related to the study of the open port city from the perspective of comparative historical research.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.431-436
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• 2010

Recently, several open source codes for computational fluid dynamics (CFD) have been emerged and are spreading fast. Our group has chosen OpenFOAM as a platform to develop our own in-house code. In this paper, we would like to share the information on the codes and what we have experienced so far. We introduce several features of OpenFOAM, which include the performance compared with commercial packages, estimation for current user population and our own prospect for future improvement in performance and growth in user population. In addition, we briefly introduce our experience gained in embedding the level set method into the OpenFOAM.

• 한국전산유체공학회지
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• 제15권3호
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• pp.46-53
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• 2010

Recently, several open source codes for computational fluid dynamics (CFD) have been introduced and are spreading fast. Our group has chosen the OpenFOAM as a platform to develop our own in-house code. In this brief review, we would like to share the information on the codes and what we have experienced so far. We introduce several features of OpenFOAM, which include the performance compared with commercial packages, estimation for current user population, and our own prospect for future improvement in performance and growth in user population. In addition, we briefly introduce our experience gained in embedding the level set method into the OpenFOAM.