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A NOTE ON Z-IDEALS IN BCI-SEMIGROUPS

  • Ahn, Sun-Shin;Kim, Hee-Sik
    • Communications of the Korean Mathematical Society
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    • v.11 no.4
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    • pp.895-902
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    • 1996
  • In this paper, we describe the ideal generated by non-empty stable set in a BCI-group as a simple form, and obtain an equivalent condition of prime Z-ideal.

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A Hierarchical Packet Classification Algorithm Using Set-Pruning Binary Search Tree (셋-프루닝 이진 검색 트리를 이용한 계층적 패킷 분류 알고리즘)

  • Lee, Soo-Hyun;Lim, Hye-Sook
    • Journal of KIISE:Information Networking
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    • v.35 no.6
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    • pp.482-496
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    • 2008
  • Packet classification in the Internet routers requires multi-dimensional search for multiple header fields for every incoming packet in wire-speed, hence packet classification is one of the most important challenges in router design. Hierarchical packet classification is one of the most effective solutions since search space is remarkably reduced every time a field search is completed. However, hierarchical structures have two intrinsic issues; back-tracking and empty internal nodes. In this paper, we propose a new hierarchical packet classification algorithm which solves both problems. The back-tracking is avoided by using the set-pruning and the empty internal nodes are avoided by applying the binary search tree. Simulation result shows that the proposed algorithm provides significant improvement in search speed without increasing the amount of memory requirement. We also propose an optimization technique applying controlled rule copy in set-pruning.

A Study on the Equalization of Pneumatic Brake-Release Performance between Various Freight Cars (이종(異種) 화물열차의 제동-완해 공기압성능 균등화에 관한 연구)

  • Nam, Seong-Won;Moon, Kyung-Ho;Lee, Dong-Hyung
    • Proceedings of the KSME Conference
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    • 2001.06b
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    • pp.525-532
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    • 2001
  • Experimental study has been conducted to clarify the pneumatic characteristics of brake system for freight train and enhance the performance of diaphragm valve. Empty-load and diaphragm brake systems are mainly used in the freight trains of KNR (Korean National Railroad). The train set is composed of thirty freight cars and diesel locomotive. From the experimental results, new quick release valve shortens release time after brake application. In case of normal brake application, the release time is short by 34% of that of original diaphragm control valve. It will be expected to assure brake-release application and reduce maintenance efforts.

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Analysis of Empty Minislot Distribution in the FlexRay Dynamic Segment (FlexRay 프로토콜의 동적 구간에서의 잔여 미니 슬롯 확률 분포 분석)

  • Bongjun Kim;Kiejin Park
    • Proceedings of the Korea Information Processing Society Conference
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    • 2008.11a
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    • pp.936-939
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    • 2008
  • 차량 내부 네트워크(In-Vehicle Network)에 많은 관심이 고조되는 가운데 Time-Triggered 와 Event-Triggered 패러다임의 장점을 모두 갖춘 하이브리드(Hybrid) 프로토콜인 FlexRay 가 최근 들어 많은 자동차 분야 업체들로부터 주목 받으면서 이에 대한 다양한 성능 분석 시도가 이루어지고 있다. 하지만 FlexRay 프로토콜의 메시지 전송의 유연성(Flexibility)으로 인해 정확한 성능 분석에 많은 어려움이 있다. 이에 본 논문에서는 다양한 길이의 메시지를 고려한 동적 구간 분석 모델을 제안하였고, 이를 바탕으로 잔여 미니 슬롯 확률 분포(Empty Minislot Distribution)를 도출하였으며 FlexRay 메시지 셋(Set)를 이용한 실험을 통하여 특정 길이의 동적 구간에서 미니 슬롯 개수에 따른 잔여 미니 슬롯 발생확률 값의 변화를 확인하였다.

Effectiveness of Bellyboard Device for Displacement of Small Bowel in Pelvic Irradiation (골반 방사선치료 시 소장의 위치변화를 위한 벨리보드의 유용성)

  • Lee, Rena;Lee, Kyung-Ja;Suh, Hyunsuk
    • Progress in Medical Physics
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    • v.18 no.4
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    • pp.202-208
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    • 2007
  • Various techniques were evaluated to determine the best method for reducing small bowel involvement in pelvic irradiation. Fourteen patients receiving radiation in pelvic area were enrolled for this study. Five sets of small bowel images were obtained. Patients were positioned on a simulation couch with full bladder in prone and supine positions and 2 sets of images were taken. Then they were asked to empty their bladder and 2 sets of images were taken in prone and supine positions. A belly board device (BBD) was placed and one set of images was obtained. Using a software, the area of small bowel inside treatment field was contoured, measured, and analyzed. In both full and empty bladder cases, small bowel area reduction was observed in prone position as compared to supine position. Especially statistically significant reduction is noted in lateral film. An average decreases of 13% in PA and 26% in lateral direction were noted with bladder distention as compared to empty bladder. With the use of BBD for empty bladder, a significant reduction of $62.8{\pm}27.1%$ and $63.1{\pm}32.9%$ in PA and lateral directions were observed as compared to without BBD in prone position, respectively. In conclusion, the best sparing of small bowel concerning the area included in the treatment fields was achieved with BBD in prone position with empty bladder. However, further reduction is expected if the bladder was filled fully because the analysed data with empty vs full bladder study shows increased sparing of small bowel with distended bladder.

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Static Analysis In Computer Go By Using String Graph (컴퓨터 바둑에서 String Graph를 사용한 정적분석)

  • 박현수;김항준
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.41 no.4
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    • pp.59-66
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    • 2004
  • We define a SG(String Graph) and an ASG(Alive String Graph) to the purpose to do static analysis. For a life and death judgment, we apply the rule to the situation which the stone is included and not included. We define the rules that are SR(String Reduction), ER(Empty Reduction), ET(Edge Transform), and CG(Circular Graph), when the stone is not included. We define the rules that are DESR(Dead Enemy Strings Reduction) and SCSR(Same Color String Reduction), when the stone is included. We evaluate a SG that it is an ASG or not by using rules. And we use APC(Articulation Point Check) nile according to number of articulation points lot a life and death judgment. The performance of our method has been tested on the problem set IGS_31_counted form the Computer Go Test Collection. The test set contains 11,191 Points and 1,123 Strings. We obtain 92.5% accuracy of Points and 95.7% accuracy of Strings.

FERMATEAN FUZZY TOPOLOGICAL SPACES

  • IBRAHIM, HARIWAN Z.
    • Journal of applied mathematics & informatics
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    • v.40 no.1_2
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    • pp.85-98
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    • 2022
  • The purpose of this paper is to introduce the notion of Fermatean fuzzy topological space by motivating from the notion of intuitionistic fuzzy topological space, and define Fermatean fuzzy continuity of a function defined between Fermatean fuzzy topological spaces. For this purpose, we define the notions of image and the pre-image of a Fermatean fuzzy subset with respect to a function and we investigate some basic properties of these notions. We also construct the coarsest Fermatean fuzzy topology on a non-empty set X which makes a given function f from X into Y a Fermatean fuzzy continuous where Y is a Fermatean fuzzy topological space. Finally, we introduce the concept of Fermatean fuzzy points and study some types of separation axioms in Fermatean fuzzy topological space.

HEWITT REALCOMPACTIFICATIONS OF MINIMAL QUASI-F COVERS

  • Kim, Chang Il;Jung, Kap Hun
    • Korean Journal of Mathematics
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    • v.10 no.1
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    • pp.45-51
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    • 2002
  • Observing that a realcompactification Y of a space X is Wallman if and only if for any non-empty zero-set Z in Y, $Z{\cap}Y{\neq}{\emptyset}$, we will show that for any pseudo-Lindel$\ddot{o}$f space X, the minimal quasi-F $QF({\upsilon}X)$ of ${\upsilon}X$ is Wallman and that if X is weakly Lindel$\ddot{o}$, then $QF({\upsilon}X)={\upsilon}QF(X)$.

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ON 4-EQUIVALENCED ASSOCIATION SCHEMES

  • PARK, JEONG RYE
    • Bulletin of the Korean Mathematical Society
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    • v.52 no.5
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    • pp.1683-1709
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    • 2015
  • Let (${\Omega}$, S) be an association scheme where ${\Omega}$ is a non-empty finite set and S is a partition of ${\Omega}{\times}{\Omega}$. For a positive integer k we say that (${\Omega}$, S) is k-equivalenced if each non-diagonal element of S has valency k. In this paper we focus on 4-equivalenced association schemes, and prove that they are transitive.

ORBITAL SHADOWING PROPERTY

  • Honary, Bahman;Bahabadi, Alireza Zamani
    • Bulletin of the Korean Mathematical Society
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    • v.45 no.4
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    • pp.645-650
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    • 2008
  • Let M be a generalized homogeneous compact space, and let Z(M) denotes the space of homeomorphisms of M with the $C^0$ topology. In this paper, we show that if the interior of the set of weak stable homeomorphisms on M is not empty then for any open subset W of Z(M) containing only weak stable homeomorphisms the orbital shadowing property is generic in W.