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231.
《Optimization》2012,61(3):237-244
In this paper, we consider a class of nonlinear optimal control problems (Bolza-problems) with constraints of the control vector, initial and boundary conditions of the state vectors. The time interval is fixed. Our approach to parametrize both the state functions and the control functions is described by general piecewise polynomials with unknown coefficients (parameters), where a fixed partition of the time interval is used. Here each of these functions in a suitable way individually will be approximated by such polynomials. The optimal control problem thus is reduced to a mathematical programming problem for these parameters. The existence of an optimal solution is assumed. Convergence properties of this method are not considered in this paper. 相似文献
232.
Existence of time periodic solutions for the 3-D viscous primitive equations of large-scale dry atmosphere
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In this paper, we consider the existence of time periodic solutions of the 3-D viscous primitive equations of large-scale dry atmosphere. We used the Galerkin method. Firstly, by Leray-Schauder fixed point theorem, we prove the existence of approximate solutions of the primitive equations, then we show the convergence of the approximate solutions, and we also get the uniqueness to the primitive equations. 相似文献
233.
Dirk Hachenberger 《Discrete Mathematics》2010,310(22):3246-3250
The present paper is a continuation of the author’s work (Hachenberger (2001) [3]) on primitivity and complete normality. For certain 2-power extensions E over a Galois field Fq, we are going to establish the existence of a primitive element which simultaneously generates a normal basis over every intermediate field of E/Fq. The main result is as follows: Letq≡3mod4and letm(q)≥3be the largest integer such that2m(q)dividesq2−1; ifE=Fq2l, wherel≥m(q)+3, then there exists a primitive element inEthat is completely normal overFq.Our method not only shows existence but also gives a fairly large lower bound on the number of primitive completely normal elements. In the above case this number is at least 4⋅(q−1)2l−2. We are further going to discuss lower bounds on the number of such elements in r-power extensions, where r=2 and q≡1mod4, or where r is an odd prime, or where r is equal to the characteristic of the underlying field. 相似文献
234.
Philippe G. CIARLET 《数学年刊B辑(英文版)》2010,31(5):607-618
Two models based on the hydrostatic primitive equations are proposed. The first model is the primitive equations with partial viscosity only, and is oriented towards large-scale wave structures in the ocean and atmosphere. The second model is the viscous primitive equations with spectral eddy viscosity, and is oriented towards turbulent geophysical flows. For both models, the existence and uniqueness of global strong solutions are established. For the second model, the convergence of the solutions to the solutions of the classical primitive equations as eddy viscosity parameters tend to zero is also established. 相似文献
235.
Mingli Hong 《Journal of Applied Analysis & Computation》2017,7(1):102-118
Here we consider the global well-posedness of the 3D viscous primitive equations of the large-scale ocean. Inspired by the methods in Cao etc\cite{CT3} and Guo etc\cite{GH2}, we prove the global well-posedness and the long-time dynamics for the primitive equations. 相似文献
236.
Classical results by Behrend, Erdös, Pillai, Szemerédi, the authors, and others are improved and extended to other concepts of densities in two directions, based on smooth and multiplicative weightings. 相似文献
237.
Xu Xiang 《数学年刊B辑(英文版)》1995,16(2):255-260
POINTEDREPRESENTATIONSOFINFINITEDIMENSIONALLIEALGEBRAS¥XUXIANGAbstract:AcontravariedbilinearpairingXoneveryM(ρ)×M(ρθ)isdeterm... 相似文献
238.
关于可约布尔矩阵幂敛指数的一个Brualdi─Ross型上界 总被引:1,自引:0,他引:1
蒋志明 《高校应用数学学报(A辑)》1994,(4)
本文证明了可约布尔矩阵幂敛指数的一个Brualdi-Ross型上界,并给出了幂敛指数达到此上界的矩阵的完全刻划. 相似文献
239.
对称本原矩阵广义上指数的极矩阵 总被引:3,自引:0,他引:3
本文以伴随图的形早了对称本原矩阵和迹零对称本原矩阵的广义上指数的极矩阵。 相似文献
240.
Flow-injection-hydride generation procedure for Se in electrolytic manganese was optimized by means of the experimental design approach. Instrumental variables like power supplied (P), sample (F) and argon (G) flow rates together with chemical variables like NaBH4 and HCl concentrations were studied. In case of the chemical variables, it was concluded that sodium tetrahydridoborate concentrations higher than 1.0% extinguished the plasma while HCl concentration should always be higher than 0.6 mol dm−3. The analysis of effects suggested that all the instrumental variables are significant factors, and the optimum conditions were P = 1550 W, F = 4.75 mL min−1 and G = 0.6 mL min−1. The influence of Mn was specially studied and it was concluded that the interferences were negligible if Mn is below 2.0 g L−1. In the same sense, the interferences of antimony(III), arsenic(V) and mercury(II) were also considered negligible. Finally, a detection limit of 0.0005% (w/w) was obtained (a repeatability R.S.D. <2.0% for all Se concentrations tried). Some manganese samples were also spiked with different concentrations of Se(IV) and the results demonstrated to be in good statistical agreement with expected values. 相似文献