• 제목/요약/키워드: explicit group

검색결과 152건 처리시간 0.023초

INFINITE FAMILIES OF RECURSIVE FORMULAS GENERATING POWER MOMENTS OF TERNARY KLOOSTERMAN SUMS WITH SQUARE ARGUMENTS ASSOCIATED WITH O-(2n, q)

  • Kim, Dae-San
    • 대한수학회지
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    • 제48권2호
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    • pp.267-288
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    • 2011
  • In this paper, we construct eight infinite families of ternary linear codes associated with double cosets with respect to certain maximal parabolic subgroup of the special orthogonal group $SO^-$(2n, q). Here q is a power of three. Then we obtain four infinite families of recursive formulas for power moments of Kloosterman sums with square arguments and four infinite families of recursive formulas for even power moments of those in terms of the frequencies of weights in the codes. This is done via Pless power moment identity and by utilizing the explicit expressions of exponential sums over those double cosets related to the evaluations of "Gauss sums" for the orthogonal groups $O^-$(2n, q).

GENERATORS OF COHOMOLOGY GROUPS OF CYCLOTOMIC UNITS

  • Kim, Jae Moon;Oh, Seung Ik
    • Korean Journal of Mathematics
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    • 제5권1호
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    • pp.61-74
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    • 1997
  • Let $d$ be a positive integer with $d\not{\equiv}2$ mod 4, and let $K=\mathbb{Q}({\zeta}_{pd})$ for S an odd prime $p$ such that $p{\equiv}1$ mod $d$. Let $K_{\infty}={\bigcup}_{n{\geq}0}K_n$ be the cyclotomic $\mathbb{Z}_p$-extension of $K=K_0$. In this paper, explicit generators for the Tate cohomology group $\hat{H}^{-1}$($G_{m,n}$ are given when $d=qr$ is a product of two distinct primes, where $G_{m,n}$ is the Galois group Gal($K_m/K_n$) and $C_m$ is the group of cyclotomic units of $K_m$. This generalizes earlier results when $d=q$ is a prime.

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RBF Neural Network Based SLM Peak-to-Average Power Ratio Reduction in OFDM Systems

  • Sohn, In-Soo
    • ETRI Journal
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    • 제29권3호
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    • pp.402-404
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    • 2007
  • One of the major disadvantages of the orthogonal frequency division multiplexing system is high peak-to-average power ratio (PAPR). Selected mapping (SLM) is an efficient distortionless PAPR reduction scheme which selects the minimum PAPR sequence from a group of independent phase rotated sequences. However, the SLM requires explicit side information and a large number of IFFT operations. In this letter we investigate a novel PAPR reduction method based on the radial basis function network and SLM.

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GREEN'S EQUIVALENCES OF BIRGET-RHODES EXPANSIONS OF FINITE GROUPS

  • Choi, Keun-Bae;Lee, Ja-Eun;Lim, Yong-Do
    • 대한수학회보
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    • 제43권2호
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    • pp.353-375
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    • 2006
  • In this paper we establish a counting method for the Green classes of the Birget-rhodes expansion of finite groups. As an application of the results, we derive explicit enumeration formulas for the Green classes for finite groups of order pq and a finite cyclic group of order $p^m$, where p and q are arbitrary given distinct prime numbers.

FREE AND NEARLY FREE CURVES FROM CONIC PENCILS

  • Dimca, Alexandru
    • 대한수학회지
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    • 제55권3호
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    • pp.705-717
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    • 2018
  • We construct some infinite series of free and nearly free curves using pencils of conics with a base locus of cardinality at most two. These curves have an interesting topology, e.g. a high degree Alexander polynomial that can be explicitly determined, a Milnor fiber homotopy equivalent to a bouquet of circles, or an irreducible translated component in the characteristic variety of their complement. Monodromy eigenspaces in the first cohomology group of the corresponding Milnor fibers are also described in terms of explicit differential forms.

연산자로서의 유리수 체계의 구성에 관한 연구

  • 정영우;김부윤
    • East Asian mathematical journal
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    • 제28권2호
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    • pp.135-158
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    • 2012
  • The ideals of the rings of integers are used to induce rational number system as operators(=group homomorphisms). We modify this inducing method to be effective in teaching rational numbers in secondary school. Indeed, this modification provides a nice model for explaining the equality property to define addition and multiplication of rational numbers. Also this will give some explicit ideas for students to understand the concept of 'field' efficiently comparing with the integer number system.

THE HILBERT-KUNZ MULTIPLICITY OF TWO-DIMENSIONAL TORIC RINGS

  • Choi, Sang-Ki;Hong, Seok-Young
    • 대한수학회지
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    • 제40권2호
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    • pp.169-177
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    • 2003
  • Recently, K. Watanabe Showed that the Hilbert-Kunz multiplicity of a toric ring is a rational number. In this paper we give an explicit formula to compute the Hilbert-Kunz multiplicity of two-dimensional toric rings. This formula also shows that the Hilbert-Kunz multiplicity of a two-dimensional non-regular toric ring is at least 3/2.

Xcast 기술 동향 (Trends on Xcast Technologies)

  • 신명기;김용진
    • 전자통신동향분석
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    • 제16권5호통권71호
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    • pp.85-93
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    • 2001
  • 본 고에서는 최근 IETF를 중심으로 새롭게 제안되고 있는 Xcast(Explicit Multicast) 기술에 관해 소개한다. Xcast 멀티캐스트 방식은 IBM의 SGM(Small Group Multicast), Alcatel의 CLM(Connectionless Multicast), Fujitsu의 MDO6(Multiple Destination Option for IPv6) 제안을 수정, Xcast로 통합한 것으로 기존 IP 멀티캐스트 방식과는 달리, IP 패킷 내에 수신자 목록을 명시적으로 포함하여 전송함으로써 소규모 그룹 통신을 위해 적합한 새로운 멀티캐스트 통신 방식이다. 본 고에서는 Xcast 기본 프로토콜 규격을 중심으로 최근 기술동향 및 국내 Xcast-KR 연구동향 등을 소개한다.

The Critical Phenomena of a Model for the Metabolic Control System with Positive Feedback

  • Kim, Cheol-Ju;Lee, Dong- J.;Shin, Kook-Joe;Lee, Jong-Myung;Ko, Seuk-Beum;Jeon, Il-Cheol
    • Bulletin of the Korean Chemical Society
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    • 제10권5호
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    • pp.452-458
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    • 1989
  • The static and dynamic phenomena of a model for the metabolic control system with positive feedback are discussed with the static and dynamic renormalization group theory. Then, the explicit results for the static and dynamic exponents are obtained up to the second order of ${\varepsilon}$-expansion, ${\varepsilon}$ being 4-d, where d is the space dimensionality of the system.

인스턴트 메신저를 이용한 집단의사결정에서 커뮤니케이션 패턴이 의사결정만족도에 미치는 영향에 대한 통합분석 (Mixed Analysis on Group Communication Pattern and Decision-making Satisfaction with Instant Messenger)

  • 박상혁
    • 한국정보시스템학회지:정보시스템연구
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    • 제15권2호
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    • pp.247-270
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    • 2006
  • This study identifies communication patterns of groups using Instant Messenger for their group decision-making, and examines how these patterns are associated with creative solutions to problems. Our research suggests that certain communication behavior of groups, when appropriately organized, can be of help in enhancing creative production of outcomes. A qualitative study was conducted on communication patterns based on an analysis of text-based electronic conversation protocols. Specifically this research tried to overcome existing studies on electronic groups by focusing on interactive process of communication among participants. The major study conclusions are: (1) Satisfation of group decision-making may depend on the process or sequence of discussion among group members with Instant Messenger. That is, proper interactive responses and appropriate control of the discussion process are essential to obtain a high level of performance. (2) It is important to ]mike discuss rules based on meta-cognitive and interactive protocols in the early stage. Explicit rules relating to internal group processes as well as communication medium use are even more important to groups with Instant Messenger than face-to-face groups.

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