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991.
992.
Zdzis?aw Skupień 《Discrete Mathematics》2009,309(22):6382-6390
We construct multigraphs of any large order with as few as only four 2-decompositions into Hamilton cycles or only two 2-decompositions into Hamilton paths. Nevertheless, some of those multigraphs are proved to have exponentially many Hamilton cycles (Hamilton paths). Two families of large simple graphs are constructed. Members in one class have exactly 16 hamiltonian pairs and in another class exactly four traceable pairs. These graphs also have exponentially many Hamilton cycles and Hamilton paths, respectively. The exact numbers of (Hamilton) cycles and paths are expressed in terms of Lucas- or Fibonacci-like numbers which count 2-independent vertex (or edge) subsets on the n-path or n-cycle. A closed formula which counts Hamilton cycles in the square of the n-cycle is found for n≥5. The presented results complement, improve on, or extend the corresponding well-known Thomason’s results. 相似文献
993.
In this paper, the numerical modelling of the flow through the low‐pressure steam turbine last stage was presented. On the basis of predicted wet steam flow‐field, the aerodynamic as well as thermodynamic losses were estimated. For calculations of the wet steam steady flow‐field three numerical methods were employed. The first method was a streamline curvature method (SCM). The commercial CFD code (CFX‐TACflow) and an in‐house code, both solving the 3‐D RANS equations, were the next two methods. In the wet steam region, by means of all three methods, the equilibrium flow was modelled. Additionally, the in‐house CFD code was used for modelling of the non‐equilibrium steam condensing flow. In this work, the comparison of the cascade loss coefficient for stator and rotor and selected flow parameters for the stage were presented, compared and discussed. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
994.
In this paper we give necessary and sufficient conditions for blow-up of solutions for a particular class of nonlinear Volterra equations. We also give some examples. 相似文献
995.
Alexander Blokh Michał Misiurewicz Nándor Simányi 《Communications in Mathematical Physics》2006,266(1):239-265
We investigate the rotation sets of billiards on the m-dimensional torus with one small convex obstacle and in the square with one small convex obstacle. In the first case the displacement function, whose averages we consider, measures the change of the position of a point in the universal covering of the torus (that is, in the Euclidean space), in the second case it measures the rotation around the obstacle. A substantial part of the rotation set has usual strong properties of rotation sets.The first author was partially supported by NSF grant DMS 0456748.The second author was partially supported by NSF grant DMS 0456526.The third author was partially supported by NSF grant DMS 0457168. 相似文献
996.
Wo Gouwei Qin Taiyan Tang Renji 《Acta Mechanica Solida Sinica》1994,7(4):354-366
By using the hypothesis of the deformation of the straight bar and beamin mechanics of materials,a new engineering calculating model for a linear inclusion inplane is presented.Through the Kelvin's solution of a concentrated force,the inclusionproblem is reduced to solving a set of uncoupled singular integral equations which canbe solved by the numerical method of singular integral equation.Based on theseresults,several applicable examples including an inclusion-crack problem are calculatedand the results are quite satisfactory. 相似文献
997.
998.
The performance of three-colour HgCdTe photovoltaic heterostructure detector is examined theoretically. In comparison with
two-colour detectors with two back-to-back junctions, three-colour structure contains an absorber of intermediate wavelength
placed between two junctions and electronic barriers are used to isolate this intermediate region. This structure was first
proposed by British workers.
Three-detector structures with different localizations of separating barriers are analyzed. The calculation results are presented
in the form of spatial distributions of bandgap energy and quantum efficiency.
Enhanced original computer programs are applied to solve the system of non-linear continuity equations for carriers and Poisson
equations. In addition, the numerical analysis includes the dependence of absorption coefficient on Burstein effect as well
as interference effects in heterostructure with metallic electrical contacts.
It is shown that the performance of the detector is critically dependent on the barrier’s doping level and position in relation
to the junction. This behaviour is serious disadvantage of the considered three-colour detector. A small shift of the barrier
location and doping level causes serious changes in spectral responsivity. 相似文献
999.
The finite-size scalling analysis of the scaled factorial moment data is proposed. This analysis allows to extract the scaling indices of the underlying higher-dimensional scale-invariant multiparticle distributions. Moreover, it exhibits the change of the effective scale involved in the dimensional projection with transverse momentum cuts applied to the data. 相似文献
1000.
A simple method for the preparation of biologically active abscisic acid (growth inhibiting plant hormone) labeled with tritium is described. The product obtained has a specific radioactivity of 1.12 GBq mmol–1: the yield is about 60% as compared to the initial amount of the substance used. 相似文献