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91.
We present an example showing that the multilinear version of the Bartle-Graves Selection Theorem is false, even on finite dimensional spaces.
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Xavier Fernandez Josep Maria Salla Angels Serra Ana Mantecn Xavier Ramis 《Journal of polymer science. Part A, Polymer chemistry》2005,43(15):3421-3432
3,4‐Epoxycyclohexylmethyl 3,4‐epoxycyclohexane carboxylate (ECH) was cured with different proportions of 1,6‐dioxaspiro [4,4]nonane‐2,7‐dione (s(γ‐BL)) using lanthanum triflate as a catalyst. The shrinkage undergone during curing was monitored by means of thermomechanical analysis (TMA) in isothermal experiments. Fourier transform infrared spectroscopy in attenuated‐total‐reflection mode (FTIR/ATR) was used to study the evolution of lactone, epoxide, and intermediate spiroorthoester (SOE) groups to identify the different reactions that take place during the curing process. DSC was used to study the thermal characteristics of the curing process and to assess the glass‐transition temperature (Tg) of the cured material. The dynamic mechanical properties of the cured material were determined based on the data obtained by DMTA. An increase in the proportion of s(γ‐BL) led to a decrease in the gelation time and the shrinkage after gelation. By combining the data obtained by TMA and FTIR/ATR, it was also possible to identify the reactive processes responsible for the shrinkage. It was observed that an increase in the proportion of s(γ‐BL) also increases the speed of the curing process and modifies the structure of the material, thus giving rise to more flexible materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3421–3432, 2005 相似文献
95.
Cristina Bazgan W. Fernandez de la Vega Marek Karpinski 《Random Structures and Algorithms》2003,23(1):73-91
It is known that large fragments of the class of dense Minimum Constraint Satisfaction (MIN‐CSP) problems do not have polynomial time approximation schemes (PTASs) contrary to their Maximum Constraint Satisfaction analogs. In this paper we prove, somewhat surprisingly, that the minimum satisfaction of dense instances of kSAT ‐formulas, and linear equations mod 2, Ek‐LIN2, do have PTASs for any k. The MIN‐Ek‐LIN2 problems are equivalent to the k‐ary versions of the Nearest Codeword problem, the problem which is known to be exceedingly hard to approximate on general instances. The method of solution of the above problems depends on the development of a new density sampling technique for k‐uniform hypergraphs which could be of independent interest. © 2003 Wiley Periodicals, Inc. Random Struct. Alg., 23: 73–91, 2003 相似文献
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Stefan T. Ochsenbein Dr. Floriana Tuna Dr. Marzio Rancan Rachel S. G. Davies Christopher A. Muryn Dr. Oliver Waldmann Dr. Roland Bircher Dr. Andreas Sieber Dr. Graham Carver Dr. Hannu Mutka Dr. Felix Fernandez‐Alonso Dr. Andrew Podlesnyak Dr. Larry P. Engelhardt Dr. Grigore A. Timco Dr. Hans U. Güdel Prof. Dr. Richard E. P. Winpenny Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(17):5087-5087
98.
G. Fernandez 《Journal of sound and vibration》1984,96(1):37-43
For a submerged cable, the classical equation of a vibrating string must be modified to account for added mass and damping effects. This can be done with the aid of Morison's formulae. The resulting equation is non-linear. It is solved for the case when one end of the string is forced into sinusoidal transverse motion. The first harmonic approximations for both resonant and non-resonant responses are obtained by the method of matched asymptotic expansions under the assumption that the non-dimensional damping coefficient is small. 相似文献
99.
W Fernandez de la Vega 《Journal of Combinatorial Theory, Series B》1983,35(3):328-332
For any tournament T on n vertices, let h(T) denote the maximum number of edges in the intersection of T with a transitive tournament on the same vertex set. Sharpening a previous result of Spencer, it is proved that, if Tn denotes the random tournament on n vertices, then, as n → ∞. 相似文献
100.
S.J. Barish M. Derrick T. Dombeck L.G. Hyman B. Musgrave P. Schreiner R. Singer M. Szczekowski V.E. Barnes D.D. Carmony E. Fernandez A.F. Garfinkel 《Physics letters. [Part B]》1977,66(3):291-294
Results are presented of a study of inclusive ηp and ηn interactions from threshold to 6 GeV. The data show a rapid approach to the distributions expected in the naive quark-parton model. The charged-current η deuteron total cross section is fit by the expression σT(ηd) = (0.76 ± 0.03) × 10?38Eη cm2 per GeV per nucleon. For Eη > 1.5 GeV, we measure σT(ηn)/σT(ηp) = (2.02 ± 0.23). The distributions in the scaling variables x and y are given and discussed. 相似文献