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71.
We generalize a smoothing algorithm for finite min–max to finite min–max–min problems. We apply a smoothing technique twice,
once to eliminate the inner min operator and once to eliminate the max operator. In mini–max problems, where only the max
operator is eliminated, the approximation function is decreasing with respect to the smoothing parameter. Such a property
is convenient to establish algorithm convergence, but it does not hold when both operators are eliminated. To maintain the
desired property, an additional term is added to the approximation. We establish convergence of a steepest descent algorithm
and provide a numerical example. 相似文献
72.
E. Koltay D. Berényi I. Kiss S. Ricz G. Hock J. Bacsó 《Zeitschrift für Physik A Hadrons and Nuclei》1976,25(5):299-302
K-shell ionization cross sections have been determined for Cr, Cu and In at proton bombardment in the energy region from 0.9 to 2.5 MeV. The same cross sections were determined for Cr and Cu at alpha bombardment in the 0.9–4.0 MeV region. The experimental results are compared with five different theoretical calculations. 相似文献
73.
Thermoanalytical processes involving the splitting-off of ammonia, water, halogens, inorganic acids or acid anhydrides can be simply observed by using a specimen-holder in which specific reactions with the decomposition products can be induced. A special glass or quartz double crucible can be used for this purpose; the products arising in the lower part of the crucible can be oxidized selectively with reagents placed in the upper part, or can be bound or transformed into other compounds. This double crucible is also suitable for studying reactions taking place between solid and gaseous substances. 相似文献
74.
75.
The synthesis and transformation of oripavidine ( 8 ) offer an efficient and simple route to highly active dopamine agonist apomorphines and a variety of important 14β‐hydroxy‐morphinan derivatives. Natural origin thebaine ( 6 ), the starting compound of the procedure, was converted into its N‐{[1,2‐bis(ethoxycarbonyl)hydrazinyl]methyl} counterpart. L ‐Selectride was found to be an efficient agent to perform a one‐pot O‐ and N‐deprotection at positions 3 and 17, respectively. 相似文献
76.
E.I. Baranov B.Y. Ber A.P. Vasil’ev A.E. Chernyakov A.G. Kolmakov D.Yu. Kazanthev V.V. Mikhrin N.A. Maleev A.M. Nadtochy V.N. Petrov N.M. Shmidt E.B. Yakimov 《Superlattices and Microstructures》2009,45(4-5):332-336
The data of Atomic Force Microscopy (AFM) surface monitoring and of mobility investigations in the HEMT structures based on the AlGaAs/InGaAs/GaAs heterostructures with pseudomorphic InGaAs channel are presented. The level of HEMT nanomaterial self-organization (LNSO) were obtained using the treatment the AFM data by the method of multifractal analysis. Direct correlation between the mobility values and LNSO was found for the most of studied HEMT structures that reflect the close relation between the LNSO values and the HEMT bulk properties. In the structures with LNSO changing from 1.13 to 1.45 the 1.5 time mobility decrease at 300 K and 4 times at 77 K was observed. The results obtained allow to suppose that the LNSO calculation based on surface monitoring of HEMT structures can be used for the optimization of their parameters and of their formation process. 相似文献
77.
78.
P. Rzezacz C. Holthaus J. S. Chotinski W. J. Bogomolow B. G. Šimek J. Ludmila B. Štanclová M. P. Perederi J. C. Macrae A. M. Wandless J. Menderssohn I. J. Lane M. P. Lonskaja J. Pfanhauser C. Fijalkowski M. D. Shukowskaja F. Coufalik H. E. Crossley D. J. Jones E. L. Buller H. A. J. Pieters Z. Beránek E. Wölk J. Pulkrábek 《Analytical and bioanalytical chemistry》1937,111(2-4):136-141
79.
M. G. Gornov M. N. Ber Yu. B. Gurov S. V. Lapushkin P. V. Morokhov V. A. Pechkurov N. O. Poroshin V. G. Sandukovsky M. V. Tel’kushev B. A. Chernyshev 《JETP Letters》2003,77(7):344-348
The formation of the 5H superheavy hydrogen isotope was experimentally sought in the reactions induced by stopped π? mesons absorbed by 9Be nuclei. Peaks in missing-mass spectra were observed in two reaction channels, 9Be(π?, pt)X and 9Be(π?, dd)X, and were attributed to the 5H resonance states. The lowest state has parameters Er=5.5±0.2 MeV and Г=5.4±0.5 MeV [Er is the resonance energy measured from the (triton + two neutrons) threshold]. Therefore, 5H is bound more weakly than 4H. Excited states of 5H were also observed. All three resonance levels (E1r=10.6±0.3 MeV, Г1r=6.8±0.5 MeV; E2r=18.5±0.4 MeV, Г2r=4.8±1.3 MeV; E3r=26.7±0.4 MeV, Г3r=3.6±1.3 MeV) can decay into five free nucleons. 相似文献
80.
Nuno P. Faísca Vivek Dua Berç Rustem Pedro M. Saraiva Efstratios N. Pistikopoulos 《Journal of Global Optimization》2007,38(4):609-623
We propose a global optimisation approach for the solution of various classes of bilevel programming problems (BLPP) based
on recently developed parametric programming algorithms. We first describe how we can recast and solve the inner (follower’s)
problem of the bilevel formulation as a multi-parametric programming problem, with parameters being the (unknown) variables
of the outer (leader’s) problem. By inserting the obtained rational reaction sets in the upper level problem the overall problem
is transformed into a set of independent quadratic, linear or mixed integer linear programming problems, which can be solved
to global optimality. In particular, we solve bilevel quadratic and bilevel mixed integer linear problems, with or without
right-hand-side uncertainty. A number of examples are presented to illustrate the steps and details of the proposed global
optimisation strategy. 相似文献