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71.
Elena?F.?ShekaEmail author Ekaterina?A.?Nikitina Valentin?A.?Zayets Ilya?Ya.?Ginzburg Joop?Schoonman 《Journal of nanoparticle research》2005,7(2-3):171-186
The current paper presents results of a quantum-chemical study of the surface structure of nanoparticles of both rutile and anatase crystallographic modifications. Different stages of the surface relaxation are discussed. Water adsorption is considered. The calculations were performed in the spd-basis by using semi-empirical quantum-chemical codes, both sequential and parallel. The results are mainly addressed to the study of the interface formed by titania nanoparticles and a set of carboxylated species, namely, benzoic, bi-isonicotinic acids as well as tris-(2,2′-dcbipyridine) Fe(II) complex placed on the surface of either rutile or anatase polymorphs.This revised version was published online in August 2005 with a corrected issue number. 相似文献
72.
David Masson 《Designs, Codes and Cryptography》2003,28(3):283-302
We study (generalized) designs supported by words of given composition. We characterize them in terms of orthogonality relations with Specht modules; we define some zonal functions for the symmetric group and we give a closed formula for them, indexed on ordered pair of semi-standard generalized tableaux: Hahn polynomials are a particular case. We derive an algorithm to test if a set is a design. We use it to search designs in some ternary self-dual codes. 相似文献
73.
superconformal algebra is
algebra with two Virasoro operators. The Kac determinant is calculated and the complete list of unitary representations is determined. Two types of extensions of
algebra are discussed. A new approach to construction of
algebras from rational conformal field theories is proposed. 相似文献
74.
Manju Pruthi 《Proceedings Mathematical Sciences》2001,111(4):371-379
In this paper explicit expressions ofm + 1 idempotents in the ring
are given. Cyclic codes of length 2
m
over the finite fieldF
q, of odd characteristic, are defined in terms of their generator polynomials. The exact minimum distance and the dimension
of the codes are obtained. 相似文献
75.
In this paper, we classify all optimal linear[n, n/2] codes up to length 12. We show that thereis a unique optimal [10, 5, 5] code up to equivalence. 相似文献
76.
In this paper, new codes of dimension 8 are presented which give improved bounds on the maximum possible minimum distance of ternary linear codes. These codes belong to the class of quasi-twisted (QT) codes, and have been constructed using a stochastic optimization algorithm, tabu search. Twenty three codes are given which improve or establish the bounds for ternary codes. In addition, a table of upper and lower bounds for d
3(n, 8) is presented for n 200. 相似文献
77.
One of the most important problems of coding theory is to constructcodes with best possible minimum distances. In this paper, we generalize the method introduced by [8] and obtain new codes which improve the best known minimum distance bounds of some linear codes. We have found a new linear ternary code and 8 new linear codes over
with improved minimumdistances. First we introduce a generalized version of Gray map,then we give definition of quasi cyclic codes and introduce nearlyquasi cyclic codes. Next, we give the parameters of new codeswith their generator matrices. Finally, we have included twotables which give Hamming weight enumerators of these new codes. 相似文献
78.
William J. Martin 《Designs, Codes and Cryptography》2000,21(1-3):181-187
A code C F
n is s-regular provided, forevery vertex x F
n, if x is atdistance at most s from C then thenumber of codewords y C at distance ifrom x depends only on i and the distancefrom x to C. If denotesthe covering radius of C and C is -regular,then C is said to be completely regular. SupposeC is a code with minimum distance d,strength t as an orthogonal array, and dual degrees
*. We prove that d 2t + 1 whenC is completely regular (with the exception of binaryrepetition codes). The same bound holds when C is(t + 1)-regular. For unrestricted codes, we show thatd s
* + t unless C is a binary repetitioncode. 相似文献
79.
Long Gui-lu Deng Fu-guo Wang Chuan Li Xi-han Wen Kai Wang Wan-ying 《Frontiers of Physics in China》2007,2(3):251-272
In this review article, we review the recent development of quantum secure direct communication (QSDC) and deterministic secure
quantum communication (DSQC) which both are used to transmit secret message, including the criteria for QSDC, some interesting
QSDC protocols, the DSQC protocols and QSDC network, etc. The difference between these two branches of quantum communication
is that DSQC requires the two parties exchange at least one bit of classical information for reading out the message in each
qubit, and QSDC does not. They are attractive because they are deterministic, in particular, the QSDC protocol is fully quantum
mechanical. With sophisticated quantum technology in the future, the QSDC may become more and more popular. For ensuring the
safety of QSDC with single photons and quantum information sharing of single qubit in a noisy channel, a quantum privacy amplification
protocol has been proposed. It involves very simple CHC operations and reduces the information leakage to a negligible small
level. Moreover, with the one-party quantum error correction, a relation has been established between classical linear codes
and quantum one-party codes, hence it is convenient to transfer many good classical error correction codes to the quantum
world. The one-party quantum error correction codes are especially designed for quantum dense coding and related QSDC protocols
based on dense coding.
相似文献
80.