• Title/Summary/Keyword: unitary

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TWO UNITARY LIGHT CURVES OF AR LACERTAE IN 1984

  • Park, Hong-Suh;Chen, Kwan-Yu
    • Journal of The Korean Astronomical Society
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    • v.23 no.2
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    • pp.106-111
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    • 1990
  • Photoelectric observation in 1984 shows light variation outside eclipses. The effect of the changing ambient temperature on the light curves were studied. Difficulty of studying and unitary, or mean, light curve of AR Lac is stressed.

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CONSTRUCTION OF CARTESIAN AUTHENTICATION CODES OVER UNTITRAY GEOMETRY

  • Xu, Wenyan;Gao, You
    • Journal of applied mathematics & informatics
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    • v.27 no.5_6
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    • pp.1481-1488
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    • 2009
  • A construction of Cartesian authentication codes over unitary geometry is presented and its size parameters are computed. Assuming that the encoding rules are chosen according to a uniform probability distribution, the probabilities of success for different types of attacks are also computed.

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Geometric Interpretation of the Unitary Jones Matrix and Its Vectorial Representation (유니타리 존즈행렬의 기하학적 해석과 벡터표현)

  • 노봉규;김진승
    • Korean Journal of Optics and Photonics
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    • v.5 no.1
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    • pp.25-30
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    • 1994
  • We derive a set of formuale which show one-to-one correspondence between the the unitary Jones matrices of transparent anisotropic media and the rotational transformations on the Poincare sphere. By using the formuale one can determine the vectorial representation of the rotational transformation on the Poincare sphere which specifies the direction of the axis and the angle of the rotation in terms of the three parameters specific to the corresponding unitary Jones matrix, and conversely the the three parameters of the uniatry Jones matrix in terms of the vectorial representation of the corresponding rotational transformation on the Poincare sphere. To understand the polarization transmission characteristics of an optical system consisting of transparent linear anisotropic media, start with the Jones calculus to get the unitary Jones matrix for the whole system and then convert it to a rotational transformation on the Poincare sphere, from which we can intuitively understand the effect of the optical system on the polarization state of the light passing through the system.

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Spatial Multiplexing System based on Random Unitary Beamforming for MU-MIMO Broadcast Channel (다중사용자 다중송수신안테나 Broadcast 채널에서의 RUB 기반 공간다중화 시스템)

  • Park, Seong-Ho;Park, Ki-Hong;Lee, Jin-Hee;Ko, Young-Chai;Kim, Sung-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.2A
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    • pp.105-111
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    • 2010
  • Random unitary beamforming (RUB) is a very low complexity and practical transmission scheme for multiuser MIMO broadcast channel. In this paper, we propose the scheme that obtains the spatial multiplexing gain on the extension of the conventional RUB, that is, the receiver with two antennas is compared to that with one antenna in a conventional RUB, which results in the increased capacity. So, we propose the new codebook and the minimum mean square error successive interference cancellation (MMSE-SIC) receiver filter. We show the simulation result that the sum-rate of proposed system is increased.

An Efficient Scheme to Achieve Differential Unitary Space-Time Modulation on MIMO-OFDM Systems

  • Liu, Shou-Yin;Chong, Jong-Wha
    • ETRI Journal
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    • v.26 no.6
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    • pp.565-574
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    • 2004
  • Differential unitary space-time modulation (DUSTM) has emerged as a promising technique to obtain spatial diversity without intractable channel estimation. This paper presents a study of the application of DUSTM on multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems with frequency-selective fading channels. From the view of a correlation analysis between subcarriers of OFDM, we obtain the maximum achievable diversity of DUSTM on MIMO-OFDM systems. Moreover, an efficient implementation strategy based on subcarrier reconstruction is proposed, which transmits all the signals of one signal matrix in one OFDM transmission and performs differential processing between two adjacent OFDM blocks. The proposed method is capable of obtaining both spatial and multipath diversity while reducing the effect of time variation of channels to a minimum. The performance improvement is confirmed by simulation results.

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UNITARY INTERPOLATION ON AX = Y IN A TRIDIAGONAL ALGEBRA ALG𝓛

  • JO, YOUNG SOO;KANG, JOO HO;PARK, DONGWAN
    • Honam Mathematical Journal
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    • v.27 no.4
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    • pp.649-654
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    • 2005
  • Given operators X and Y acting on a separable complex Hilbert space ${\mathcal{H}}$, an interpolating operator is a bounded operator A such that AX = Y. We show the following: Let $Alg{\mathcal{L}}$ be a subspace lattice acting on a separable complex Hilbert space ${\mathcal{H}}$ and let $X=(x_{ij})$ and $Y=(y_{ij})$ be operators acting on ${\mathcal{H}}$. Then the following are equivalent: (1) There exists a unitary operator $A=(a_{ij})$ in $Alg{\mathcal{L}}$ such that AX = Y. (2) There is a bounded sequence {${\alpha}_n$} in ${\mathbb{C}}$ such that ${\mid}{\alpha}_j{\mid}=1$ and $y_{ij}={\alpha}_jx_{ij}$ for $j{\in}{\mathbb{N}}$.

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INTERVAL-VALUED FUZZY GROUP CONGRUENCES

  • Lee, Jeong Gon;Hur, Kul;Lim, Pyung Ki
    • Honam Mathematical Journal
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    • v.38 no.2
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    • pp.403-423
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    • 2016
  • We introduce the concepts of interval-valued fuzzy complete inner-unitary subsemigroups and interval-valued fuzzy group congruences on a semigroup. And we investigate some of their properties. Also, we prove that there is a one to one correspondence between the interval-valued fuzzy complete inner-unitary subsemigroups and the interval-valued fuzzy group congruences on a regular semigroups.

ABSTRACT RANDOM LINEAR OPERATORS ON PROBABILISTIC UNITARY SPACES

  • Tran, Xuan Quy;Dang, Hung Thang;Nguyen, Thinh
    • Journal of the Korean Mathematical Society
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    • v.53 no.2
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    • pp.347-362
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    • 2016
  • In this paper, we are concerned with abstract random linear operators on probabilistic unitary spaces which are a generalization of generalized random linear operators on a Hilbert space defined in [25]. The representation theorem for abstract random bounded linear operators and some results on the adjoint of abstract random linear operators are given.

Strongly Solid Varieties and Free Generalized Clones

  • Denecke, Klaus
    • Kyungpook Mathematical Journal
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    • v.45 no.1
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    • pp.33-43
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    • 2005
  • Clones are sets of operations which are closed under composition and contain all projections. Identities of clones of term operations of a given algebra correspond to hyperidentities of this algebra, i.e., to identities which are satisfied after any replacements of fundamental operations by derived operations ([7]). If any identity of an algebra is satisfied as a hyperidentity, the algebra is called solid ([3]). Solid algebras correspond to free clones. These connections will be extended to so-called generalized clones, to strong hyperidentities and to strongly solid varieties. On the basis of a generalized superposition operation for terms we generalize the concept of a unitary Menger algebra of finite rank ([6]) to unitary Menger algebras with infinitely many nullary operations and prove that strong hyperidentities correspond to identities in free unitary Menger algebras with infinitely many nullary operations.

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Design and performance analysis of the linear phase para-unitary M bandfilter bank with application to image coding (영상 부호화를 위한 LPPU M 대역 필터군의 설계와 성능 분석)

  • 이창우;김종원;이상욱
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.5
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    • pp.1141-1154
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    • 1996
  • The para-unitary (PU) M band filter bank, which can beused for M band decomposition, has many useful properties. In this ppaer, attempts have been made to design and and analyze the linear phase para-unitary (LPPU) M band filter bank, which is appropriate to the image coding application. First, we derive a unified coding gain in terms of the correlation in the band, as well as the energy compaction. And M band filter bank has been designed, maximizing the new coding gain. Then, we analyze the image coding performance of the LPPU M band filter bank, such as the energy compaction, the correlation in the band and the entropy. From the analysis, it is shown that the coding gain for LPPU M band filter bank improves, and the coding gain for the LPPU 4 band filter bank approaches very closely to that for LPPU 8 band filter bank, as the length of the filter increases. This fact is also verified by the coding results on the real images.

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