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441.
In this article, we proposed a new scheme to encrypt highly autocorrelated image pixel data. In existing literature, single substitution was used to break autocorrelation in images. To get better results, instead of single substitution box, some researchers are minimizing the autocorrelation via utilizing multiple substitution boxes. However, we found that multiple substitution boxes cannot solve the problem of autocorrelation independently. Therefore, we added chaotic confusion and diffusion to the existing substitution scheme in order to remove the correlation completely. Initially, we break the autocorrelation of data by permuting the pixels via TD-ERCS chaotic map. Bitwise XOR is carried out for diffusion using logistic map followed by the existing substitution scheme. Experimental analysis shows that the proposed scheme has greater resistance to brute force attack and statistical attack. Further analyses such as statistical analysis, peak signal-to-noise ratio, contrast analysis, key space analysis, entropy analysis, correlation analysis, key sensitivity analysis, and encryption quality analysis proved the high robustness of the proposed scheme. 相似文献
442.
Poblaguev AA Appel R Atoyan GS Bassalleck B Bergman DR Cheung N Dhawan S Do H Egger J Eilerts S Herold W Issakov VV Kaspar H Kraus DE Lazarus DM Lichard P Lowe J Lozano J Ma H Majid W Pislak S Rehak P Sher A Thompson JA Truöl P Zeller ME 《Physical review letters》2002,89(6):061803
Experiment 865 at the Brookhaven Alternating Gradient Synchrotron obtained 410 K+-->e(+)nue(+)e(-) and 2679 K+-->mu(+)nue(+)e(-) events including 10% and 19% background. The branching ratios were measured to be [2.48+/-0.14(stat)+/-0.14(syst)]x10(-8) (m(ee)>150 MeV) and (7.06+/-0.16+/-0.26)x10(-8) (m(ee)>145 MeV), respectively. Results for the decay form factors are presented. 相似文献
443.
Z. Gulácsi 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,30(3):295-301
We report for the first time exact ground-states deduced for the D
= 2 dimensional generic periodic Anderson model at finite U, the Hamiltonian of the model not containing direct hopping terms for f-electrons (
t
f
= 0). The deduced itinerant phase presents non-Fermi liquid properties in the normal phase, emerges for real hybridization matrix
elements, and not requires anisotropic unit cell. In order to deduce these results, the plaquette operator procedure has been
generalised to a block operator technique which uses blocks higher than an unit cell and contains f-operator contributions acting only on a single central site of the block.
Received 1st July 2002 / Received in final form 16 September 2002 Published online 19 December 2002
RID="a"
ID="a"e-mail: gulacsi@heavy-ion.atomki.hu 相似文献
444.
The effect of spherulite growth (diameter 25 to 185 µ) on the adhesive properties and density of polypropylene is studied. The adhesive properties are evaluated in terms of adhesive power and adhesion susceptibility. It is shown that, as distinct from the cohesive strength, the strength of adhesive joints in which polypropylene is used as substrate and SKB butadiene elastomer as adhesive increases somewhat with the diameter of the spherulites, while the density of the polypropylene increases linearly. It is suggested that the observed increase in adhesion susceptibility is due to surface development associated with the growth of the spherulites.Mekhanika Polimerov, Vol. 1, No. 3, pp. 3–7, 1965 相似文献
445.
The problem concerning the explosion of a cord charge in the ground, with a hard upper layer, is considered in pulse formulation. A numerical solution is obtained and profiles are given for the throwout craters for several values of thickness of the layer and emplacement depth of the charge, in two limiting cases: when the resistance of the lower ground is negligibly small in comparison with the resistance of the layer and when the resistance of the ground and layer are quite close in magnitude.Translated from Zhurnal Prikladnoi Mekhanika i Tekhnicheskoi Fiziki, No. 2, pp. 143–146, March–April, 1973. 相似文献
446.
Khan SB Afza N Malik A ul Haq A Ahmed Z 《Magnetic resonance in chemistry : MRC》2004,42(12):1063-1065
Ramosine, a new sesquiterpene lactone, was isolated from the chloroform fraction of Amberboa ramosa and the structure was assigned as 4beta-(hydroxymethyl)-3beta,4alpha-dihydroxy-8alpha-[(S)-3-hydroxy-2-ethylenepropionyloxy]-1alphaH, 5alphaH,6betaH,7alphaH,11betaH,11alpha-methylguaia-10(14)-en-6, 12-olide by extensive NMR studies. 相似文献
447.
[reaction: see text] Readily available 4-propargyl-1,3-cyclohexanediones and cyclopentanediones can be chemo- and regioselectively cycloisomerized to synthetically appealing fused oxabicyclic systems by simply stirring at room temperature with catalytic amounts of an appropriate metal complex. 相似文献
448.
Computer simulation of multiphoton excitation of SF6 molecules cooled by pulsed supersonic expansion
V. Toşa I. Deac P. Mercea Zs. Gulácsi V. Mercea 《Applied physics. B, Lasers and optics》1985,36(1):55-57
The initial ground-state dependence of the multiphoton excitation of SF6 is numerically estimated using two different approximations for thev
3 vibration-rotation levels and for the laser line width. From this calculations we have identified and explained some features seen in recent experimental data. 相似文献
449.
450.