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941.
S. Marinetti D. Robba F. Cernuschi P.G. Bison E. Grinzato 《Infrared Physics & Technology》2007,49(3):281-285
When performing in-field tests on thermal barrier coatings (TBCs) deposited on gas turbine blades, the main problem encountered is the difficulty to correctly interpret the experimental data. The coating thickness changes, which are not regarded as anomalies, are one of the most common sources of false alarms. They are very challenging to recognize because, unlike stains, eroded areas and optical property variations, they are not detectable in the visible band. Furthermore, their thermal signal is similar to the one produced by an adhesion defect. In this paper, a procedure to reliably discriminate thickness changes and real defects is proposed. The approach is based on the analysis of the apparent effusivity profile. Preliminary results are presented and discussed. 相似文献
942.
Results are presented of an experimental investigation of vortex ring formation by a fluid drop contacting a free surface
with negligible velocity. The pool fluid is mixed with fluorescein dye, and a laser sheet is used to illuminate a plane of
the flow. A series of representative images is recorded by a CCD camera and speculation is made regarding specific sources
of vorticity flux through the free surface. Two scaling analyses previously presented by other investigators are demonstrated
to be equivalent under the assumptions of this experiment, and they provide the motivation for a series of test runs in which
the duration of the coalescence process, τ*, is related to variations in drop diameter L and fluid surface tension σ. Experimental results are in agreement with the analyses, showing τ*∼σ-1/2 and τ*∼L
3/2.
Received: 22 December 1995 / Accepted: 15 October 1996 相似文献
943.
We prove that directly reducible lattices and selfdual subdirectly irreducible lattices of locally finite length are determined by their sublattice-lattices. As a corollary we obtain that splitting varieties are closed under the isomorphism of sublattice-lattices iff they are selfdual. A class of selfdual non-closed varieties is given too. 相似文献
944.
Protein Conformation of a Lattice Model Using Tabu Search 总被引:1,自引:0,他引:1
We apply tabu search techniques to the problem of determining the optimal configuration of a chain of protein sequences on a cubic lattice. The problem under study is difficult to solve because of the large number of possible conformations and enormous amount of computations required. Tabu search is an iterative heuristic procedure which has been shown to be a remarkably effective method for solving combinatorial optimization problems. In this paper, an algorithm is designed for the cubic lattice model using tabu search. The algorithm has been tested on a chain of 27 monomers. Computational results show that our method outperforms previously reported approaches for the same model. 相似文献
945.
I.G. Kalinina K.Z. Gumargalieva Yu.A. Shlyapnikov 《Polymer Degradation and Stability》1993,40(3):411-416
p-Toluensulfonic acid retards oxidation of polyethylene and, to a greater extent, of polyethylene-poly-p-methylstyrene blends. The real antioxidant is p-cresol, formed by p-toluensulfonic acid transformation in oxidizing polyethylene and, in blends, through peroxidation and subsequent acid-catalyzed decomposition of hydroperoxides of poly-p-methylstyrene. 相似文献
946.
G. Mastroianni 《Numerical Algorithms》1995,10(1):113-126
The author gives some upper and lower bounds for the generalized Christoffel functions related to a Ditzian-Totik generalized weight. As an application, an error estimate of Gauss quadrature formula inL
1-weighted norm is derived.Dedicated to Prof. Luigi Gatteschi on the occasion of his 70th birthdayWork sponsored by MURST 40%. 相似文献
947.
By exploiting the construction of charged field algebras as canonical extensions of CCR current algebras in 1+1 dimensions and nonregular representations of extended algebras, we provide an algebraic construction of local Fermi fields as ultrastrong limits of bosonic variables in all representations which are locally Fock with respect to the ground-state representation of the massless scalar field. 相似文献
948.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, p. 2899, December, 1991. 相似文献
949.
We obtain sufficient conditions for the oscillation of all solutions of the higher order neutral differential equation dn/dm[y(t) + P(t) y(t - μ)] + Q(t) y(t ?σ) = 0, t ≧ t0 where n ≧ 1, P ? C[t0, ∞), R ], Q ? C[t0, ∞), R ] and τ, μ ? R +. Our results extend and improve several known results in the literature. 相似文献
950.