• 제목/요약/키워드: discrete group

검색결과 244건 처리시간 0.024초

CONSTRUCTIONS OF SEGAL ALGEBRAS IN L1(G) OF LCA GROUPS G IN WHICH A GENERALIZED POISSON SUMMATION FORMULA HOLDS

  • Inoue, Jyunji;Takahasi, Sin-Ei
    • 대한수학회지
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    • 제59권2호
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    • pp.367-377
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    • 2022
  • Let G be a non-discrete locally compact abelian group, and 𝜇 be a transformable and translation bounded Radon measure on G. In this paper, we construct a Segal algebra S𝜇(G) in L1(G) such that the generalized Poisson summation formula for 𝜇 holds for all f ∈ S𝜇(G), for all x ∈ G. For the definitions of transformable and translation bounded Radon measures and the generalized Poisson summation formula, we refer to L. Argabright and J. Gil de Lamadrid's monograph in 1974.

효율적인 그룹키 분배 및 갱신을 위한 보안 프로토콜의 설계 (The Design of Security Protocol for An Efficient Distribution and Renewal Method of Group Key)

  • 오명욱;김성열;배용근;정일용
    • 정보처리학회논문지C
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    • 제9C권3호
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    • pp.331-336
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    • 2002
  • 본 논문에서는 신분확인 프로토콜에 기반을 둔 그룹 비밀키의 분배와 갱신을 위한 효율적인 프로토콜을 제안한다. 제안된 프로토콜의 안전성은 이산대수 문제에 근거하고 있으며 단말기의 저장능력과 처리 능력이 적을 경우도 적절하게 운영될 수 있고, 그룹 내에서 제외하고자하는 단말기가 동시에 여러 대일 경우에도 적용할 수 있다. 또한 센터가 그룹 비밀키를 변경하고자 하는 경우에도 용이하게 키를 갱신할 수 있도록 설계되었다.

Embedded micro processor를 이용한 저항용접기용 SCR 위상제어장치 개발 (Development of SCR Phase Controller of SPOT Welder using an Embedded u-Processor)

  • 이영준;최영준;최용범;양항준;홍순욱;이학성
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 F
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    • pp.2578-2580
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    • 1999
  • In this paper, an embedded micro processor based resistance spot welding controller is introduced which has been recently developed by Hyosung Co. Ltd. The performance of rapid and constant high current control is tested experimentally. This paper shows configurations of measuring system for high current and realtime RMS conversion techniques of sampled discrete data. A digital proportional control is adopted for this system and the result shows that this new product is working well at wide range of welding current and the performance is improved compared with some other commercially available controllers that are widely used in our industries. User friendly MMI system and a computer network system to monitor each welding processes are also presented.

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PATTERSON-SULLIVAN MEASURE AND GROUPS OF DIVERGENCE TYPE

  • Hong, Sungbok
    • 대한수학회보
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    • 제30권2호
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    • pp.223-228
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    • 1993
  • In this paper, we use the Patterson-Sullivan measure and results of [H] to show that for a nonelementary discrete group of divergence type, the conical limit set .LAMBDA.$_{c}$ has positive Patterson-Sullivan measure. The definition of the Patterson-Sullivan measure for groups of divergence type is reviewed in section 2. The Patterson-Sullivan measure can also be defined for groups of convergence type and the details for that case can be found in [N]. Necessary definitions and results from [H] are given in section 3, and in section 4, we prove our main result.t.

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A Form-finding Technique for Three-dimensional Spatial Structures

  • Lee, Sang Jin
    • Architectural research
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    • 제15권4호
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    • pp.207-214
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    • 2013
  • A form-finding technique is proposed for three-dimensional spatial structures. Two-step discrete finite element (FE) mesh generator based on computer aided geometric design (CAGD) is introduced and used to control the shape of three-dimensional spatial structures. Mathematical programming technique is adopted to search new forms (or shapes) of spatial structures. For this purpose, the strain energy is introduced as the objective function to be minimized and the initial volume (or the initial weight) is considered as constraint function. Numerical examples are carried out to test the capability of the proposed form-finding techniques and provided as benchmark tests.

THICKLY SYNDETIC SENSITIVITY OF SEMIGROUP ACTIONS

  • Wang, Huoyun
    • 대한수학회보
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    • 제55권4호
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    • pp.1125-1135
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    • 2018
  • We show that for an M-action on a compact Hausdorff uniform space, if it has at least two disjoint compact invariant subsets, then it is thickly syndetically sensitive. Additionally, we point out that for a P-M-action of a discrete abelian group on a compact Hausdorff uniform space, the multi-sensitivity is equivalent to both thick sensitivity and thickly syndetic sensitivity.

CONVEX DECOMPOSITIONS OF REAL PROJECTIVE SURFACES. III : FOR CLOSED OR NONORIENTABLE SURFACES

  • Park, Suh-Young
    • 대한수학회지
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    • 제33권4호
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    • pp.1139-1171
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    • 1996
  • The purpose of our research is to understand geometric and topological aspects of real projective structures on surfaces. A real projective surface is a differentiable surface with an atlas of charts to $RP^2$ such that transition functions are restrictions of projective automorphisms of $RP^2$. Since such an atlas lifts projective geometry on $RP^2$ to the surface locally and consistently, one can study the global projective geometry of surfaces.

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디지탈압축 기초기술

  • 통신위성우주산업연구회
    • 위성통신과 우주산업
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    • 제2권2호
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    • pp.115-124
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    • 1994
  • 디지틀압축의 이용이 급속히 확대되어 가고 있다. 메모리와 논리회로의 진보에 따라 경제성이 좋아지고 있다. 디지틀압축은 예측, 변환, 양자화, 부호화의 과정을 거쳐, 각 과정에 화상정보를 압축하여 전체 전송하는 데이타량을 대폭 감소시켰다. 특히 중요한 것은 화상정보의 주파수성분을 분석하는 변환으로 실용화가 진행중인 기술로서 DCT(Discrete Cosine Transform)가 있다. 특히 MPEG(Moving Picture Expert Group) 등 압축방식의 표준화기구에서는 DCT를 주축으로 연구가 행해지고 있다.

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Parametric Tests and Estimation of Mean Change in Discrete Distributions

  • Kim, Jae-Hee;Cheon, Soo-Young
    • Communications for Statistical Applications and Methods
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    • 제16권3호
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    • pp.511-518
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    • 2009
  • We consider the problem of testing for change and estimating the unknown change-point in a sequence of time-ordered observations from the binomial and Poisson distributions. Including the likelihood ratio test, Gombay and Horvath (1990) tests are studied and the proposed change-point estimator is derived from their test statistic. A power study of tests and a comparison study of change-point estimators are done via simulation.

REMARKS ON DIGITAL HOMOTOPY EQUIVALENCE

  • Han, Sang-Eon
    • 호남수학학술지
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    • 제29권1호
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    • pp.101-118
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    • 2007
  • The notions of digital k-homotopy equivalence and digital ($k_0,k_1$)-homotopy equivalence were developed in [13, 16]. By the use of the digital k-homotopy equivalence, we can investigate digital k-homotopy equivalent properties of Cartesian products constructed by the minimal simple closed 4- and 8-curves in $\mathbf{Z}^2$.