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In this paper the improved photometric or the so called “Shape From Shading” method is presented. In comparison to known and established approaches the efficiency of the detector system was considered and the requirements of the cosine Lambert’s law for the angle distribution of the emitted electrons are suppressed. The method retrieves more accurate data of sub-micrometer substructures like diffractive optical elements (DOE) due to an increased lateral resolution and works more efficiently than widely used comparable techniques.  相似文献   
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In this paper, we consider a discrete fractional boundary value problem of the form: where 0 < α,β≤1, 1 < α + β≤2, λ and ρ are constants, γ > 0, , is a continuous function, and Eβx(t) = x(t + β ? 1). The existence and uniqueness of solutions are proved by using Banach's fixed point theorem. An illustrative example is also presented. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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The effect of heat treatments on the electrical responses of the electrode and surface layer in a giant-permittivity CuO ceramic is investigated. It is found that the giant low-frequency relative permittivity of the CuO ceramic can be tuned by annealing in Ar and O2—it can be reduced by annealing in Ar, and then it can be enhanced up to the initial value by annealing in O2. The results indicate to the effect of oxygen vacancy concentration on the giant dielectric properties of the CuO ceramic. Interestingly, three sets of dielectric relaxations are observed in the O2–annealed sample, which can be assigned as the effects of outmost surface layer, electrode, and grain boundary. Our results reveal that the giant low-frequency dielectric response in the CuO ceramic is associated with both of the interfacial polarization at the sample–electrode interface resulted from a non-Ohmic electrode contact and the outmost surface layer-inner part interface.  相似文献   
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Journal of Sol-Gel Science and Technology - Pure orthorhombic phase of La1?xSmxFeO3 (x?=?0, 0.1, 0.2, and 0.3) nanoparticles can be obtained by sol–gel method after...  相似文献   
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In this paper, we study a new class of three-point boundary value problem of nonlinear Caputo fractional difference equation. Our problem contain an argument with a shift. The existence of at least one positive solution is proved by using the Guo-Krasnoselskii’s fixed point theorem. Some illustrative examples are given.  相似文献   
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In this paper, we study a new class of 3‐point boundary value problems of nonlinear fractional difference equations. Our problems contain difference and fractional sum boundary conditions. Existence and uniqueness of solutions are proved by using the Banach fixed‐point theorem, and existence of the positive solutions is proved by using the Krasnoselskii's fixed‐point theorem. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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In this paper, we consider a discrete fractional boundary value problem of the form where 0 < α,β≤1, 1 < α + β≤2, 0 < γ≤1, , ρ is a constant, and denote the Caputo fractional differences of order α and β, respectively, is a continuous function, and ?p is the p‐Laplacian operator. The existence of at least one solution is proved by using Banach fixed point theorem and Schaefer's fixed point theorem. Some illustrative examples are also presented. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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