New design-based ratio and difference estimators of the distribution function are defined by minimizing the mean square error of a class of estimators. Proposed estimators do not assume a superpopulation model between the variable of interest and the auxiliary variable. Results derived from...

We define two quantities associated to each of the vertices of a simple graph, based on the collection of minimal vertex covers of the graph. They are called covering degree and covering index. We use them to describe new strategies for measuring the robustness of a network. We study the...

The real dynamics of a family of fourth-order iterative methods is studied when it is applied on quadratic polynomials. A Scaling Theorem is obtained and the conjugacy classes are analyzed. The convergence plane is used to obtain the same kind of information as from the parameter space, and even...

We have recently developed a package in Maple that allows to perform logical computations in any existing or proposed many-valued logic (that can be defined using truth tables). It has applications in logic engineering (e.g. when creating a new logic adapted to some requirements), in theoretical...

The mechanical behavior of magnetic reading devices is mainly governed by compressible Reynolds equations when the air bearing modeling approximation is considered. First, the convection dominated feature motivates the use of a characteristics scheme adapted to steady state problems. Secondly, a...

A class of goodness-of-fit tests is considered. The test statistic of each test in this class is an L2-norm of the difference between the empirical characteristic function associated with a random sample and an estimator of the characteristic function of the population in the null hypothesis....

In this paper we investigate the existence of entropy solution for the following nonlinear elliptic equation involving p(x)-Laplacian type operator,−Δp(x)u+|u|p(x)−2u=μin a bounded set Ω⊂ℝN, coupled with a Dirichlet boundary condition. For right-hand side measure μ which admits a...

A simple solver is proposed for the numerical solution of density-driven multi-layer shallow water flows. The governing equations consist on coupling the multi-layer shallow water equations for the hydraulic variables with suspended sediment transport equations for the concentration variables....

Stand-alone hybrid renewable energy systems are more reliable than one-energy source systems. However, their design is crucial. For this reason, a new methodology with the aim to design an autonomous hybrid PV-wind-battery system is proposed here. Based on a triple multi-objective optimization...

When the data are unevenly distributed and the behaviour of a function changes abruptly, the approximant can present undue oscillations. We present an algorithm to identify a domain decomposition, such that on each subdomain the behaviour of the function is sufficiently homogeneous in order to...