• Title/Summary/Keyword: star operators

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STAR OPERATORS ON sn-NETWORKS

  • Lin, Shou;Zhang, Jinhuang
    • Communications of the Korean Mathematical Society
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    • v.27 no.3
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    • pp.621-627
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    • 2012
  • Star operations are defined by R. E. Hodel in 1994. In this paper some relations among star operators, sequential closure operators and closure operators are discussed. Moreover, we introduce an induced topology by a family of subsets of a space, and some interesting results about star operators are established by the induced topology.

ON STAR MOMENT SEQUENCE OF OPERATORS

  • Park, Sun-Hyun
    • Honam Mathematical Journal
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    • v.29 no.4
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    • pp.569-576
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    • 2007
  • Let $\cal{H}$ be a separable, infinite dimensional, complex Hilbert space. We call "an operator $\cal{T}$ acting on $\cal{H}$ has a star moment sequence supported on a set K" when there exist nonzero vectors u and v in $\cal{H}$ and a positive Borel measure ${\mu}$ such that <$T^{*j}T^ku$, v> = ${^\int\limits_{K}}\;{{\bar{z}}^j}\;{{\bar{z}}^k}\;d\mu$ for all j, $k\;\geq\;0$. We obtain a characterization to find a representing star moment measure and discuss some related properties.

RANDOM FIXED POINT THEOREMS FOR *-NONEXPANSIVE OPERATORS IN FRECHET SPACES

  • Abdul, Rahim-Khan;Nawab, Hussain
    • Journal of the Korean Mathematical Society
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    • v.39 no.1
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    • pp.51-60
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    • 2002
  • Some random fixed point theorems for nonexpansive and *-nonexpansive random operators defined on convex and star-shaped sets in a Frechet space are proved. Our work extends recent results of Beg and Shahzad and Tan and Yaun to noncontinuous multivalued random operators, sets analogue to an earlier result of Itoh and provides a random version of a deterministic fixed point theorem due to Singh and Chen.

RIQUIER AND DIRICHLET BOUNDARY VALUE PROBLEMS FOR SLICE DIRAC OPERATORS

  • Yuan, Hongfen
    • Bulletin of the Korean Mathematical Society
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    • v.55 no.1
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    • pp.149-163
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    • 2018
  • In recent years, the study of slice Dirac operators has attracted more and more attention in the literature. In this paper, Almansitype decompositions for null solutions to the iterated slice Dirac operator and the generalized slice Dirac operator are obtained without a star-like domain centered at the origin. As applications, we investigate Riquier type problems and Dirichlet type problems in the theory of slice monogenic functions.

LINEAR OPERATORS THAT PRESERVE SETS OF PRIMITIVE MATRICES

  • Beasley, Leroy B.;Kang, Kyung-Tae;Song, Seok-Zun
    • Journal of the Korean Mathematical Society
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    • v.51 no.4
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    • pp.773-789
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    • 2014
  • We consider linear operators on square matrices over antinegative semirings. Let ${\varepsilon}_k$ denote the set of all primitive matrices of exponent k. We characterize those linear operators which preserve the set ${\varepsilon}_1$ and the set ${\varepsilon}_2$, and those that preserve the set ${\varepsilon}_{n^2-2n+2}$ and the set ${\varepsilon}_{n^2-2n+1}$. We also characterize those linear operators that strongly preserve ${\varepsilon}_2$, ${\varepsilon}_{n^2-2n+2}$ or ${\varepsilon}_{n^2-2n+1}$.

A Exploratory Study on the Development of Star Menus in the Western Restaurants of the Hotels Focused on the Tourism Hotels in Seoul (호텔 양식당의 스타메뉴 개발에 관한 탐색적 연구 -서울지역 특1급 호텔을 중심으로-)

  • Lee, Eun-Jung;Lee, Jong-Kil
    • Journal of the Korean Society of Food Culture
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    • v.21 no.6
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    • pp.629-637
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    • 2006
  • This exploratory study is to analyze the status of star menus and suggest the development strategy of star menus in the western restaurants of the tourism hotels in Seoul. The data was collected from the chefs who have been working over 15-years in tourism hotels in Seoul by judgement sampling. The questionnaire was composed of Miller and Pavesic's 'Fifty tips for a successful menu' and Khan's 'The evaluation of menu item development', The 30-menu items were selected from the 1st survey on the menu items that were high in both popularity and contribution margin by menu engineering method. The selected menu items were analyzed by 14 lists: simplicity, ready availability of ingredients, quality, flavor, presentation, preparation, service method, nutrition quality, preference, profitability, serving temperature, descriptive copy of menu and publicity. As a result of the study, appetizer category was recorded the highest score by 4.09. Smoked salmon, Tomato and mozzarella cheese, Cream of mushroom, Cream of asparagus, French onion soup, Grilled beef tenderloin, Grilled rib-eye steak, Roasted lamb rack, King prawn, Seafood spaghetti, Chef's salad, Caesar salad, Organic salad, Fruit plate, Italian tiramisu and Yogurt ice cream were recorded high score. The development strategy of star menu is belows : the menu writer must consider the productivity, effectiveness, popularity and profitability, the regular customers want varieties and creativity in the menu and the operators have to include the star menu items in the set menu.

A Priority based Dynamic Spectrum Allocation Algorithm for Multiple Network Operators Supporting Multiple Service Classes (다중 서비스 클래스를 제공하는 네트워크 운영자를 위한 우선순위 기반의 동적 스펙트럼 할당 알고리즘)

  • Kim, Hoon;Joo, Yang-Ick;Yun, Sang-Boh;Lee, Yeon-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.1A
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    • pp.59-66
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    • 2008
  • This paper presents a spectrum sharing and allocation problem in multiple network operators(NOs). Most of previous works as to dynamic spectrum allocation(DSA) schemes have presented the DSA gain achieved by utilizing the time or regional variations in traffic demand between multi-network operators(NOs). In this paper, we introduce the functionalities required for the entities related with the spectrum sharing and allocation and propose a spectrum allocation algorithm while considering the long-term priority(or fairness) between NOs, the prioritybetween multiple class services, and the urgent bandwidth request. It was shown that the proposed algorithm with priorities between multiple class services could sustain better satisfaction ratio(SR) than the fixed allocation schemes or one without priority under different traffic patterns. Therefore, we conclude that the proposed DSA with priorities between multiple class services and network operators could provide the fairness between service classes of network operators and effective negotiation procedure for urgent bandwidth request by users.

A Study on the Automatic Start-up of a Drum-type Boiler Using Fuzzy Logic (퍼지 논리를 이용한 드럼형 보일러의 자동기동에 관한 연구)

  • ;;;Zeungnam Bien
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.2
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    • pp.87-96
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    • 1993
  • Because of the complexity, nonlinearity and long-time delay of power plant, the star-up operation of a fossil power plant is very difficult to automate. So the start-up operation is always carried out by the skilled human operators, who utilize their knowledges and experiences for the predesigned start-up schedules and procedures. In this paper, a fuzzy logic controller is designed for the start-up operation of the power plant. And the operators experiences are modeled in terms of fuzzy sets and variables. To validate the controller, a drum-type boiler of the Seoul Power Plant is constructed via the signal flow diagram. Using the model, the suggested automatic start-up operation is verified, and the results are also presented.

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Active Measurement Analysis of KREONET using Modified PingER

  • Lee, Man-Hui
    • Journal of Scientific & Technological Knowledge Infrastructure
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    • s.7
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    • pp.134-140
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    • 2001
  • To know about the performance of KREONET, we installed an active network performance measurement tool, PingER. For customization, we modified its architecture and some codes. Although this customization is a minor change of PingER, it gives much benefit and convenience for both operators and users. Using PingER, we can measure the effect of the STAR TAP link. The new networking through the link is a little bit slower than the previous networking. But the new link shows far fewer packet losses and provides more reliable networking.

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