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251.
In this paper, the authors first introduce the concept of congruence pairs on the class of decomposable MS-algebras generalizing that for principal MS-algebras (see [13]). They show that every congruence relation θ on a decomposable MS-algebra L can be uniquely determined by a congruence pair (θ1, θ2), where θ1 is a congruence on the de Morgan subalgebra L?? of L and θ2 is a lattice congruence on the sublattice D(L) of L. They obtain certain congruence pairs of a decomposable MS-algebra L via central elements of L. Moreover, they characterize the permutability of congruences and the strong extensions of decomposable MS-algebras in terms of congruence pairs. 相似文献
252.
A. S. Tchakoutio Nguetcho P. B. Ndjoko T. C. Kofane 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,62(1):7-14
The proton conductivity and the mobility arising from motions of the
ionic and bonded defects, in hydrogen-bonded molecular systems are
investigated by means of the quantum mechanical method. Our two component
model goes beyond the usual classical harmonic interaction by inclusion of a
quartic interaction potential between the nearest-neighbor protons. Among
the rich variety of soliton patterns obtained in this model, we focus our
attention to compact kink (kinkon) solutions to calculate analytically, the
mobility of the kinkon-antikinkon pair and the specific
electrical-conductivity of the protons transfer in the hydrogen-bonded
systems under an externally applied electrical-field through the dynamic
equation of the kinkon-antikinkon pair. For ice, the mobility and the
electrical conductivity of the proton transfer obtained are about
5.307×10-7 m2 V-1 s-1
and 6.11×10-4 Ω-1 m-1, respectively. The results
obtained are in qualitative agreement with experimental data. 相似文献
253.
Alessandra Sarti 《Mathematische Nachrichten》2008,281(7):1031-1046
In a previous paper, [12], we described six families of K 3‐surfaces (over ?) with Picard‐number 19, and we identified surfaces with Picard‐number 20. In these notes we classify some of the surfaces by computing their transcendental lattices. Moreover, we show that the surfaces with Picard‐number 19 are birational to a Kummer surface which is the quotient of a non‐product type abelian surface by an involution. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
254.
This paper presents efficient techniques for mapping FIR filter computation circuits for PAM and QAM modulators onto systolic arrays. The exploitation of the inherent symmetry of these problem instances and the use of Look-Up Tables (L.U.T.) in conjunction with the use of systolic architectures, increases the performance while keeping the VLSI area minimal. Exploiting parallelism and pipelining enhances the throughput and results in linear expandability of the FIR filter with respect to the bit accuracy and to the stage count. 相似文献
255.
In this paper, the capacity and error probability of maximal ratio combining (MRC) reception are considered for different
modulation schemes over correlated Nakagami fading channels. Based on an equivalent scalar additive white Gaussian noise (AWGN)
channel, we derive the characteristic function (CF) and the probability density function (PDF) of the signal to noise ratio
for MRC reception over Nakagami fading channels. Using these CF and PDF results, closed form error probability and capacity
expressions are obtained for PSK, PAM and QAM modulation.
Wei Li received his Ph.D. degree in Electrical and Computer Engineering from the University of Victoria in 2004. He is now a Post-doctoral
Research Fellow in the Department of Electrical and Computer Engineering at the University of Victoria. He is a Member of
the IEEE. His research interests include ultra-wideband system, spread spectrum communications, diversity for wireless communications,
and cellular communication systems.
Hao Zhang was born in Jiangsu, China, in 1975. He received his Bachelor Degree in Telecom Engineering and Industrial Management from
Shanghai Jiaotong University, China in 1994, his MBA from New York Institute of Technology, USA in 2001, and his Ph.D. in
Electrical and Computer Engineering from the University of Victoria, Canada in 2004. His research interests include ultra-wideband
radio systems, MIMO wireless systems, and spectrum communications. From 1994 to 1997, he was the Assistant President of ICO(China)
Global Communication Company. He was the Founder and CEO of Beijing Parco Co., Ltd. from 1998 to 2000. In 2000, he joined
Microsoft Canada as a Software Engineer, and was Chief Engineer at Dream Access Information Technology, Canada from 2001 to
2002. He is currently an Adjunct Assistant Professor in the Department of Electrical and Computer Engineering at the University
of Victoria.
T. Aaron Gulliver received the Ph.D. degree in Electrical and Computer Engineering from the University of Victoria, Victoria, BC, Canada in
1989. From 1989 to 1991 he was employed as a Defence Scientist at Defence Research Establishment Ottawa, Ottawa, ON, Canada.
He has held academic positions at Carleton University, Ottawa, and the University of Canterbury, Christchurch, New Zealand.
He joined the University of Victoria in 1999 and is a Professor in the Department of Electrical and Computer Engineering.
He is a Senior Member of the IEEE and a member of the Association of Professional Engineers of Ontario, Canada. In 2002, he
became a Fellow of the Engineering Institute of Canada. His research interests include information theory and communication
theory, algebraic coding theory, cryptography, construction of optimal codes, turbo codes, spread spectrum communications,
space-time coding and ultra wideband communications. 相似文献
256.
本文基于Raney的内蕴式刻划定理对偏序集引入了性质P,讨论了性质P与余素元、紧元和强紧元诸概念之间的关系,证明了链具有性质P,作为其推论知完备链为完全分配格。 相似文献
257.
258.
Axel Hultman 《Discrete Mathematics》2007,307(14):1825-1832
Natural Dowling analogues of the complex of phylogenetic trees are studied. Using discrete Morse theory, we find their homotopy types. In the process, the homotopy types of certain subposets of Dowling lattices are determined. 相似文献
259.
A study is developed focusing the loss of stability of the interface dividing two regions of different spatial patterns on a coupled map lattice using coupling as the parameter guiding the transition. These patterns are constructed over local periodic/chaotic attractors generating regions of synchronized/collective behavior. The discrete feature of the underlying lattice, the anisotropy that stems from such discreteness and its possible change to an isotropic system through coupling with large number of neighbors are also investigated. 相似文献
260.
We study an order boundedness property in Riesz spaces and investigate Riesz spaces and Banach lattices enjoying this property. 相似文献