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971.
972.
Microemulsions (dispersions of water droplets, typical radius about 10 nm, in oil) show a particular percolation pattern, a so-called dynamical percolation. Predictions of scaling theory and Monte Carlo simulations were compared with experimental static and frequency dependent conductivity data. The latter gives evidence of two different time scales of charge transport.Dedicated to Professor Harry Thomas on the occasion of his 60th birthday 相似文献
973.
P. D. Morley 《Nuclear Physics A》1987,470(3-4):547-557
We compute delta electroproduction in nuclei using a relativistic nuclear model. Iron is predicted to have the largest per nucleon cross section and narrowest width, but the variation in A is no larger than an 18% effect. Predictions are made for the SLAC NPAS NE5 experiment and a recently completed Bates laboratory experiment. 相似文献
974.
The compound binomial risk model with time-correlated claims 总被引:1,自引:0,他引:1
Yuntao Xiao 《Insurance: Mathematics and Economics》2007,41(1):124-133
In this paper, we consider the compound binomial risk model with the time-correlated claims. It is assumed that every main claim will produce a by-claim but the occurrence of the by-claim may be delayed. We obtain the recursive formula of the joint distribution of the surplus immediately prior to ruin and deficit at ruin. Furthermore, the ruin probability is given by means of ruin probability and the deficit at ruin of the classical compound binomial risk model. Finally, we derive an upper bound for the ruin probability. 相似文献
975.
UV–visible upconversion emission from terbium in a Tb–Yb codoped tellurite glass has been observed on 980-nm excitation. The
ultraviolet and violet upconversion emissions involve three photons and the blue, green, yellow, and red emissions arise due
to two incident photons. The mechanism involved in these emissions is discussed. The effects of doping concentration and of
the sample temperature on the upconversion emissions have also been studied.
PACS 74.25.Gz; 42.70.Hj; 73.61.Jc; 76.30.Kg; 42.70.Ce 相似文献
976.
Ts. A. Gavasheli D. M. Daraseliya D. L. Dzhaparidze R. I. Mirianashvili O. V. Romelashvili T. I. Sanadze 《Physics of the Solid State》2006,48(1):58-62
An empirical relationship describing the radial dependence of the nondipole part of the anisotropic constant for the ligand
hyperfine interaction in alkaline-earth fluorides is proposed. This relationship is used for calculating the distances between
the magnetic ion and the fluorine ions involved in its nearest environment. The results of the calculations are in good agreement
with the values obtained by other methods for both cubic and tetragonal fluorine centers in these crystals. The distances
from the magnetic ion to different groups of nonequivalent fluorine ions of the nearest environment in Yb3+ trigonal centers of SrF2 and BaF2 are determined. It is found that the Yb3+ ion is slightly displaced along the trigonal axis away from the compensating fluorine ion. 相似文献
977.
V. M. Nagirnyi R. D. Apostolova E. M. Shembel’ 《Russian Journal of Applied Chemistry》2006,79(9):1443-1446
The surface morphology of V2O5, Co2O3, and MnO2 electroplated under different electrolysis conditions was studied. The nature of the electrocrystallization of these materials was suggested on the basis of the analysis results. 相似文献
978.
Roberto D. Galvão Luis Gonzalo Acosta Espejo Brian Boffey 《Annals of Operations Research》2006,143(1):31-44
A study has been carried out aimed at reducing perinatal mortality in the municipality of Rio de Janeiro through a better
distribution of health care facilities. The algorithmic aspects are detailed elsewhere and here the emphasis is on practical
issues and difficulties encountered.
A 3-level hierarchical model was developed. Both uncapacitated and capacitated versions are briefly described together with
some results based on actual data. The project brought to light many contradictions between OR theory and practice in developing
countries and, unfortunately, the models developed were not implemented by the municipality health authorities. Possible reasons
for this outcome are analysed. 相似文献
979.
D Shaw 《The Journal of the Operational Research Society》2006,57(7):830-841
Problem-structuring group workshops can be used in organizations as a consulting tool and as a research tool. One example of the latter is using a problem-structuring method (PSM) to help a group tackle an organizational issue; meanwhile, researchers collect the participants’ initial views, discussion of divergent views, the negotiated agreement, and the reasoning for outcomes emerging. Technology can help by supporting participants in freely sharing their opinions and by logging data for post-workshop analyses. For example, computers let participants share views anonymously and without being influenced by others (as well as logging those views), and video-cameras can record discussions and intra-group dynamics. This paper evaluates whether technology-supported Journey Making workshops can be effective research tools that can capture quality research data when compared against theoretical performance benchmarks and other qualitative research tools. 相似文献
980.
Kang Hai TAN Xiao Ping YANG 《数学学报(英文版)》2006,22(3):701-710
In this paper we give a geometric interpretation of the notion of the horizontal mean curvature which is introduced by Danielli Garofalo-Nhieu and Pauls who recently introduced sub- Riemannian minimal surfaces in Carnot groups. This will be done by introducing a natural nonholonomic connection which is the restriction (projection) of the natural Riemannian connection on the horizontal bundle. For this nonholonomic connection and (intrinsic) regular hypersurfaces we introduce the notions of the horizontal second fundamental form and the horizontal shape operator. It turns out that the horizontal mean curvature is the trace of the horizontal shape operator. 相似文献