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991.
Ming-Xing Luo Lin Li Song-Ya Ma Xiu-Bo Chen Yi-Xian Yang 《International Journal of Theoretical Physics》2013,52(9):3032-3044
In this paper, we show that some special mixed quantum resource experience the same property of pure entanglement such as Bell state for quantum teleportation. It is shown that one mixed state and three bits of classical communication cost can be used to teleport one unknown qubit compared with two bits via pure resources. The schemes are easily implement with model physical techniques. Moreover, these resources are also optimal and typical for faithfully remotely prepare an arbitrary qubit, two-qubit and three-qubit states with mixed quantum resources. Our schemes are completed as same as those with pure quantum entanglement resources except only 1 bit additional classical communication cost required. The success probability is independent of the form of the mixed resources. 相似文献
992.
C. W. Luo 《The European Physical Journal C - Particles and Fields》1998,1(1-2):235-241
Heavy to light baryon weak form factors are investigated in a lightcone constituent quark model. In a SU(4) symmetry broken scheme, both charged and neutral weak current-induced form factors are calculated at theq 2 = 0 point including the leading relativistic effects in the spin composition of baryons. The corresponding semileptonic decays are described by assuming dipole dependence of form factors onq 2. 相似文献
993.
A 2-cell embedding f : X → S of a graph X into a closed orientable surface S can be described combinatorially by a pair M = (X;ρ ) called a map, where ρ is a product of disjoint cycle permutations each of which is the permutation of the arc set of X initiated at the same vertex following the orientation of S . It is well known that the automorphism group of M acts semi-regularly on the arc set of X and if the action is regular, then the map M and the embedding f are called regular. Let p and q be primes. Du et al. [J. Algebraic Combin., 19, 123-141 (2004)] classified the regular maps of graphs of order pq . In this paper all pairwise non-isomorphic regular maps of graphs of order 4 p are constructed explicitly and the genera of such regular maps are computed. As a result, there are twelve sporadic and six infinite families of regular maps of graphs of order 4 p ; two of the infinite families are regular maps with the complete bipartite graphs K2p,2p as underlying graphs and the other four infinite families are regular balanced Cayley maps on the groups Z4p , Z22 × Zp and D4p . 相似文献
994.
995.
亥姆霍兹线圈磁场的均匀性分析 总被引:20,自引:8,他引:20
引入磁场均匀度的概念,对亥姆霍兹线圈磁场的均匀性进行了定量分析,并通过计算机模拟,得出了同一精度下,形成亥姆霍兹线圈均匀磁场的最佳条件. 相似文献
996.
Hongjun Yan 《Mathematics and Financial Economics》2011,4(2):135-159
News about an individual stock normally has only a trivial impact on the aggregate economy. The news of the aggregate stock
market, however, may have a significant impact on the prospects of the economy, and so has a large impact on the pricing kernel.
This difference between the aggregate stock market and individual stocks is analyzed in a dynamic general equilibrium setting
with incomplete information. The main findings are as follows. First, consistent with existing empirical evidence, the correlation
between stock returns and earnings surprises is, on average, positive at the individual stock level and is lower or even negative at the aggregate level. Second, a stock’s return is less sensitive to its earnings surprises if the expected earnings growth
of the stock is more pro-cyclical. Third, a decrease of information quality of a stock increases its risk premium if the stock
accounts for a small fraction of the economy, but decreases its risk premium if the stock accounts for a large fraction. 相似文献
997.
Let R (C) T be an extension of commutative rings. T is called ω-linked over R if T as an R-module is a ω-module. In the case of R (C) T (C) Q0(R), T is called a ω-linked overring of R. As a generalization of Wang-McCsland-Park-Chang Theorem, we show that if R is a reduced ring, then R is a ω-Noetherian ring with ω-dim(R) ≤1 if and only if each ω-linked overring T of R is a ω-Noetherian ring with ω-dim(T) ≤ 1. In particular, R is a ω-Noetherian ring with ω-dim(R) = 0 if and only if R is an Artinian ring. 相似文献
998.
The spectral characteristics of mini-optically pumped NH3 cavity laser emission at 67.2μm was studied. It was found that the spectrum of 67.2μm emission was duality. With low power
CO2-9R(30) pumping condition (lp<1MW/cm2), the spectrum appeared to be two wide FIR laser lines (∼4.6GHz for each line), which were the result of competition of multi-Raman
processes. With high power pumping condition (lp>2MW/cm2), the spectrum extended to be a very wide band (∼14GHz), which was the result of the combination of the competition and interaction
enhancement of Raman processes. The wide band spectral characteristics of 67.2 μm would be significant to the tuning of NH3 OPFIRL.
Supported by theNatural Science Foundation of Guangdong Province, P.R. China. 相似文献
999.
Jun Zhang Fangwei Wang Panlin Zhang Xiangdong Sun Qiwei Yan 《Journal of magnetism and magnetic materials》1998,190(3):1085
Magnetic and electric properties of layered perovskites Nd2−2xSr1+2xMn2O7 (x=0.3, 0.4 and 0.5) are sensitive to the doping content x. The sample with x=0.5 is antiferromagnetic (AFM) and insulating. On decreasing x, the AFM ordering is suppressed and a canted AFM or weak ferromagnetic (FM) ordering appears, and the resistivity decreases. The sample with x=0.4 still shows insulating behavior, but a metal–insulator transition is observed for x=0.3. By suggesting the presence of a competition between AFM super-exchange interaction and FM double-exchange interaction, the doping dependence of magnetic and electric properties can be understood. 相似文献
1000.
In the present paper, we mainly discuss the (??,?)-generalized fuzzy rough sets introduced by B.Q. Hu and Z.H. Huang with both constructive approach and axiomatic approach considered. In the former, we started from the investigation of the properties of the ??-upper and ?-lower approximation operators generated by binary fuzzy relations. In the latter, by defining a pair of fuzzy set-theoretic operators, we show (??,?)-fuzzy rough approximation operators can be characterized by different sets of axioms. 相似文献