On the ways of generalization of adsorption kinetic equations for the case of energetically heterogeneous surfaces

In this work, we present three different ways of incorporation of the effects of surface energetic heterogeneity in the Statistical Rate Theory kinetic equation. These ways are critically discussed and finally, we come to the conclusion that the most consistent method is based on the assumption that the adsorbing surface should not be considered as composed from independent subsystems but it should be treated as one physical entity. As an illustration, we show the numerical analysis of the experimental data concerning the adsorption of CO₂ on scandia. The estimated best-fit parameters are physically correct and consistent with the results of calorimetric measurements.     

On the structure of the stochastic process of mortgages in Spain

Summary  The number of mortgages in Spain is a counting process that can be modelled as a doubly stochastic Poisson process (DSPP). A modelling method for the intensity of a DSPP is proposed. A first step consists on estimating discrete sample paths of it from observed ones of the DSPP, then a continuous modelling is derived by means of Functional Principal Component Analysis. The method is validated by a simulation. Finally, it is applied to the real process of the mortgages in Spain discussing the interpretation of the principal components and factors.     

Existence of positive solutions for fourth-order m-point boundary value problem with variable parameters

In this paper, we investigate the existence of positive solutions for a class of nonlinear fourth-order m-point boundary value problem with two variable parameters. By using the fixed point index theory, we give some new existence results.     

Geometric non-linear analysis of space frame with rotation greater than 90°, with Euler angles and quasi-fixed local axes system

The geometric non-linear analysis of space frames with definition of the local axes through rotations similar to Euler angles, presents difficulties when the rotations reach 90° in the fixed local axes. To surmount these difficulties this work presents a new technique using a system coined quasi-fixed local axes. In this technique, the direction cosines of these axes of the actual increment of loading are defined through the direction cosines of the moving local axes of the last iteration of the previous increment and of the quasi-fixed local axes of the previous increment (or fixed, in case of the first increment). The technique of definition of the quasi-fixed local axes is used with updated Lagrangian reference. The numerical examples presented herein show the great numerical stability of the technique.     

Strong Ellipticity of Transversely Isotropic Elasticity Tensors

The strong ellipticity of the elasticity tensor of a linearly hyperelastic, transversely isotropic material is investigated. The necessary and sufficient conditions for the elasticity tensor to be strongly elliptic are determined for the five constants characterizing it.     

Some new common fixed point theorems under strict contractive conditions

The main purpose of this paper is to give some new common fixed point theorems under strict contractive conditions for mappings satisfying a new property.     

数量标号对偶变维数不动点算法和组合引理

本文给出一个数量标号的八面形变维数不动点算法，它是Ｌａａｎ和Ｔａｌｍａｎ算法的对偶形式。利用这算法，证明了比Ｆｒｅｕｎｄ组合引理更强的结果。另一方面，这算法可用于计算某些连续映射的零点，且具有跟踪连通零点集的功能。     

Quasilinear systems with memory kernels

We consider a quasilinear integrodifferential system in non-normal form. Such a system is a generalization of a phase-field model with memory and includes, as a particular case, the system describing the combustion of a material with memory. In this paper, we study both the direct and the inverse problems. Our fundamental tools are: the theory of analytic semigroups, optimal regularity results and fixed point arguments.     

混合成本分解式的比较

本文对两个期间混合成本分解式中的固定成本和单位成本变动率进行比较，进而能从数量方面评价两种不同的成本管理措施优劣。