In this paper we consider the Elastic membrane equation：with memory term and nonlinear boundary damping： Under some appropriate assumptions on the relaxation function h and with certain initial data, the global exis...In this paper we consider the Elastic membrane equation：with memory term and nonlinear boundary damping： Under some appropriate assumptions on the relaxation function h and with certain initial data, the global existence of solutions ：and a general decay for the energy are established using the multiplier technique. Also, ＇we show that a nonlinear source of polynomial type is able to force solutions to blow up in finite time even in presence of a nonlinear damping.展开更多
The aim of this paper is to prove the existence of one or multiple solutions of nonlinear difference equations coupled to a general set of boundary conditions.Before to do this,we construct a discrete operator whose f...The aim of this paper is to prove the existence of one or multiple solutions of nonlinear difference equations coupled to a general set of boundary conditions.Before to do this,we construct a discrete operator whose fixed points coincide with the solutions of the problem we are looking for.Moreover,we introduce a strong positiveness condition on the related Green's function that allows us to construct suitable cones where to apply adequate fixed point theorems.Once we have the general existence result,we deduce,as a particular case,the existence of solutions of a second order difference equation with nonlocal perturbed Dirichlet conditions.展开更多
This paper deals with the problem of approximate controllability of infinite dimensional linear systems in nonreflexive state spaces. A necessary and sufficient condition for approximate controllability via L^p（[0, T...This paper deals with the problem of approximate controllability of infinite dimensional linear systems in nonreflexive state spaces. A necessary and sufficient condition for approximate controllability via L^p（[0, T], U）, 1≤p〈∞ is obtained,where L^p（ [0, T], U） is the control function space.展开更多
Ninety-four pathologic specimens of gastric mucosa with lesions including simple intestinal metaplasia, intestinal types of mild, moderate, severe dysplasia and gastric carcinoma were submitted to morphometric analysi...Ninety-four pathologic specimens of gastric mucosa with lesions including simple intestinal metaplasia, intestinal types of mild, moderate, severe dysplasia and gastric carcinoma were submitted to morphometric analysis by an automated image analysis system. Four kinds of indices and four geometric parameters were measured. They were: (1) Index of Structural Atypism (ISA); (2) Index of Glandular Formation (IGF); (3) Index of Nuclei-Gland ratio (ING); (4) Widthen of Nuclear Band (WNB); (5) Geometric parameters of cell nuclei: including Area, Perimeter, Mean Diameter, and Contour. Apart from Contour, these variables were increased with increasing degrees of atypism in the various types of gastric mucosal lesions. Hence the indices and parameters may be used as objective diagnostic criteria. An assessment model was established for discriminating various types of lesions. The coincidence rate between the model assessment and the original histopathologic diagnosis was 86.1%. Morphometric analysis may provide a means of standardizing pathologic diagnosis and grading of gastric precancerous lesions.展开更多
Let X be a metrizable space and let φ：R× X → X be a continuous flow on X. For any given {φt}-invariant Borel probability measure, this paper presents a {φt}-invariant Borel subset of X satisfying the require...Let X be a metrizable space and let φ：R× X → X be a continuous flow on X. For any given {φt}-invariant Borel probability measure, this paper presents a {φt}-invariant Borel subset of X satisfying the requirements of the classical ergodic theorem for the contiImous flow （X, {φt}）. The set is more restrictive than the ones in the literature, but it might be more useful and convenient, particularly for non-uniformly hyperbolic systems and skew-product flows.展开更多
文摘In this paper we consider the Elastic membrane equation：with memory term and nonlinear boundary damping： Under some appropriate assumptions on the relaxation function h and with certain initial data, the global existence of solutions ：and a general decay for the energy are established using the multiplier technique. Also, ＇we show that a nonlinear source of polynomial type is able to force solutions to blow up in finite time even in presence of a nonlinear damping.
基金partially supported by Xunta de Galicia(Spain),project EM2014/032 and AIE,Spain and FEDER,grant MTM2016-75140-Psupported by the Bulgarian National Science Fundation under Project DN 12/4“Advanced Analytical and Numerical Methods for Nonlinear Differential Equations with Applications in Finance and Environmental Pollution”,2017。
文摘The aim of this paper is to prove the existence of one or multiple solutions of nonlinear difference equations coupled to a general set of boundary conditions.Before to do this,we construct a discrete operator whose fixed points coincide with the solutions of the problem we are looking for.Moreover,we introduce a strong positiveness condition on the related Green's function that allows us to construct suitable cones where to apply adequate fixed point theorems.Once we have the general existence result,we deduce,as a particular case,the existence of solutions of a second order difference equation with nonlocal perturbed Dirichlet conditions.
文摘This paper deals with the problem of approximate controllability of infinite dimensional linear systems in nonreflexive state spaces. A necessary and sufficient condition for approximate controllability via L^p（[0, T], U）, 1≤p〈∞ is obtained,where L^p（ [0, T], U） is the control function space.
文摘Ninety-four pathologic specimens of gastric mucosa with lesions including simple intestinal metaplasia, intestinal types of mild, moderate, severe dysplasia and gastric carcinoma were submitted to morphometric analysis by an automated image analysis system. Four kinds of indices and four geometric parameters were measured. They were: (1) Index of Structural Atypism (ISA); (2) Index of Glandular Formation (IGF); (3) Index of Nuclei-Gland ratio (ING); (4) Widthen of Nuclear Band (WNB); (5) Geometric parameters of cell nuclei: including Area, Perimeter, Mean Diameter, and Contour. Apart from Contour, these variables were increased with increasing degrees of atypism in the various types of gastric mucosal lesions. Hence the indices and parameters may be used as objective diagnostic criteria. An assessment model was established for discriminating various types of lesions. The coincidence rate between the model assessment and the original histopathologic diagnosis was 86.1%. Morphometric analysis may provide a means of standardizing pathologic diagnosis and grading of gastric precancerous lesions.
文摘Let X be a metrizable space and let φ：R× X → X be a continuous flow on X. For any given {φt}-invariant Borel probability measure, this paper presents a {φt}-invariant Borel subset of X satisfying the requirements of the classical ergodic theorem for the contiImous flow （X, {φt}）. The set is more restrictive than the ones in the literature, but it might be more useful and convenient, particularly for non-uniformly hyperbolic systems and skew-product flows.
