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21.
In this paper we consider an obstacle control problem where the state satisfies a quasilinear elliptic variational inequality and the control function is the obstacle. The state is chosen to be close to the desire profile while the H2 norms of the obstacle is not too large. Existence and necessary conditions for the optimal control are established. 相似文献
22.
First order dynamic inclusions on time scales 总被引:1,自引:0,他引:1
F.Merdivenci Atici D.C. Biles 《Journal of Mathematical Analysis and Applications》2004,292(1):222-237
In this paper, we study existence of solutions of first order dynamic inclusions on time scales with general boundary conditions. Both the ∇-derivative and Δ-derivative cases are considered. Examples are presented to illustrate that the Δ-derivative case needs more restrictive assumptions. 相似文献
23.
Norma L. Ortiz Peter R. Wolenski 《Journal of Mathematical Analysis and Applications》2004,289(1):260-265
This note proves an existence theorem for a generalized Bolza-type problem that has time delays in both the state and velocity variables. The assumptions are stated in terms of a modification of the classical Hamiltonian, and extend ideas of Rockafellar to the delay case. 相似文献
24.
1IntroductionThemethodofupperandlowersolutionshasbecomeastandardtoolforstudyingthesolvabilityoftwo-pointboundaryvalllcproblemsassociatedwitllsecond-ordernonlineardifferentialequations.Inrecent,years,Rachunkovd[1,2,3]studiedthefour--pointboundaryvalueprobl… 相似文献
25.
Heng-You Lan 《Journal of Mathematical Analysis and Applications》2007,327(1):481-493
In this paper, we introduce and study a new system of nonlinear A-monotone multivalued variational inclusions in Hilbert spaces. By using the concept and properties of A-monotone mappings, and the resolvent operator technique associated with A-monotone mappings due to Verma, we construct a new iterative algorithm for solving this system of nonlinear multivalued variational inclusions associated with A-monotone mappings in Hilbert spaces. We also prove the existence of solutions for the nonlinear multivalued variational inclusions and the convergence of iterative sequences generated by the algorithm. Our results improve and generalize many known corresponding results. 相似文献
26.
Dong Sheng WU Yi Min XIAO 《数学学报(英文版)》2007,23(4):613-622
Let B^α = {B^α(t),t E R^N} be an (N,d)-fractional Brownian motion with Hurst index α∈ (0, 1). By applying the strong local nondeterminism of B^α, we prove certain forms of uniform Hausdorff dimension results for the images of B^α when N 〉 αd. Our results extend those of Kaufman for one-dimensional Brownian motion. 相似文献
27.
本文研究了一类中立型时滞差分方程的振动性和正解存在性,获得了该方程所有解振动的“Sharp”条件及存在正解的一个充分条件. 相似文献
28.
Positive Steady States of a Prey-predator Model with Diffusion and Non-monotone Conversion Rate 总被引:1,自引:0,他引:1
Rui PENG Ming Xin WANG Wen Van CHEN 《数学学报(英文版)》2007,23(4):749-760
In this paper, we study the positive steady states of a prey-predator model with diffusion throughout and a non-monotone conversion rate under the homogeneous Dirichlet boundary condition. We obtain some results of the existence and non-existence of positive steady states. The stability and uniqueness of positive steady states are also discussed. 相似文献
29.
Silver halide (AgX) microcrystal was used as template to synthesize hollow polyelectrolyte capsules. These hollow capsules were characterized by laser light scattering (LLS) used to measure the size of the capsules in solution. The ratio of hydrodynamic radius (Rh) from dynamic LLS to the radius of gyration (Rg) from static LLS is almost unity, revealing that the entities are hollow in solution. The results suggest that the LLS method can be regarded as a good complement to the confocal laser scanning microscopy (CLSM) method for the characterization of small hollow capsules, and it possesses the advantage of not needing fluorescence labeling. 相似文献
30.
A five-step model for a quality assurance system is developed for an internal quality control check. It includes the quality
control of the decomposition method and the detection method as steps belonging together. The Wickbold combustion technique
as decomposition method in combination with atomic absorption spectrometry was chosen. The vaporization of the elements mercury,
arsenic, lead, antimony and selenium is based on combustion in an oxyhydrogen flame. To check the efficiency of the analytical
system, the uncertainty of results was calculated on the basis of the "Guide to the Expression of Uncertainty in Measurement".
Received: 13 January 1997 · Accepted: 29 March 1997 相似文献