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271.
An exact analysis is given to explain the experimental results of Su et al. The resolving power is shown to vary from extremely good to worse than that based on the Rayleigh criterion, depending upon the location of the illuminated area on the hologram during reconstruction. 相似文献
272.
C.S. Lai 《Physics letters. A》1979,70(1):6-8
It is shown that the soliton-like solution to the nonlinear Schrödinger equation perturbed by resonance interaction can be derived by a straightforward perturbation calculation. 相似文献
273.
The strong consistency of least squares estimates in multiple regression models is established under minimal assumptions on the design and weak dependence and moment restrictions on the errors. 相似文献
274.
The stability of a curved rail under a constant moving load has been investigated using a linear theory; critical speeds of the moving load, and the dynamic rail deflections and rotation were calculated. The effect of the foundation was included through distributed linear springs. It was assumed that the moving load remains in constant contact with the rail and travels along a fixed path on the rail head. 相似文献
275.
Field theories naturally give rise to multiple jets of hadrons in short-distance processes, such as e+ e? annihilation. In particular, a low-energy jet of hadrons distributed in some cone of opening angle δ would be naively expected to evolve at high energies into multiple jets within the angle δ. We explore to what extent this will happen in quantum chromodynamics. 相似文献
276.
277.
Currently used public-key cryptosystems are based on difficulties in solving certain numeric theoretic problems, in which the way to predict the private key from the knowledge of the public key is computationally infeasible. Here we propose a method of constructing public-key cryptosystems by generalized synchronization of coupled map lattices, in which the difficulty in predicting the synchronous function is used as the trap-door function to deduce the private key from the public key. In specific, we implement this idea on the method of "Merkle's puzzles," and find that, incorporated with the chaotic dynamics, this traditional method is equipped with some new features and can be practical in certain situations. 相似文献
278.
P.T. Lai J.P. Xu C.X. Li C.L. Chan 《Applied Physics A: Materials Science & Processing》2005,81(1):159-161
The interface quality and reliability of gate oxides grown on n-/p-type 6H-SiC in diluted NO gas at 1150 °C are investigated. As compared to conventional 100%-NO oxidation, the diluted-NO (50% and 23%) oxidations lead to lower interface-state, border-trap and oxide-charge densities. This is attributed to the fact that carbon-accumulation and carbon-removal rates are closer when oxidation is performed in diluted NO, giving a smoother, less disordered and strained interface. Moreover, less degradation of the diluted-NO samples than 100%-NO samples is observed during high-field stressing (±7 MV/cm), indicating that stronger SiN bonds are created near/at the SiC/SiO2 interface for oxide grown in diluted NO ambient. PACS 85.30.Tv; 81.65.Mq; 81.05.HD; 85.30.De; 73.20.At 相似文献
279.
Marin-Montesinos I Brouwer DH Antonioli G Lai WC Brinkmann A Levitt MH 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2005,177(2):307-317
We examine the influence of continuous-wave heteronuclear decoupling on symmetry-based double-quantum homonuclear dipolar recoupling, using experimental measurements, numerical simulations, and average Hamiltonian theory. There are two distinct regimes in which the heteronuclear interference effects are minimized. The first regime utilizes a moderate homonuclear recoupling field and a strong heteronuclear decoupling field; the second regime utilizes a strong homonuclear recoupling field and a weak or absent heteronuclear decoupling field. The second regime is experimentally accessible at moderate or high magic-angle-spinning frequencies and is particularly relevant for many realistic applications of solid-state NMR recoupling experiments to organic or biological materials. 相似文献
280.
When prior partial information about a state to be cloned is available, it can be cloned with a fidelity higher than that of universal quantum cloning. We experimentally verify this intriguing relationship between the cloning fidelity and the prior information by reporting the first experimental optimal quantum state-dependent cloner, using nuclear magnetic resonance techniques. Our experiments may further cast important implications into many quantum information processing protocols. 相似文献