Search results for "Applied Mathematic"
showing 10 items of 4398 documents
Approximate Taylor methods for ODEs
2017
Abstract A new method for the numerical solution of ODEs is presented. This approach is based on an approximate formulation of the Taylor methods that has a much easier implementation than the original Taylor methods, since only the functions in the ODEs, and not their derivatives, are needed, just as in classical Runge–Kutta schemes. Compared to Runge–Kutta methods, the number of function evaluations to achieve a given order is higher, however with the present procedure it is much easier to produce arbitrary high-order schemes, which may be important in some applications. In many cases the new approach leads to an asymptotically lower computational cost when compared to the Taylor expansio…
On Variational Measures Related to Some Bases
2000
Abstract We extend, to a certain class of differentiation bases, some results on the variational measure and the δ-variation obtained earlier for the full interval basis. In particular the theorem stating that the variational measure generated by an interval function is σ-finite whenever it is absolutely continuous with respect to the Lebesgue measure is extended to any Busemann–Feller basis.
Post-Classical Islamic Philosophy – a Contradiction in Terms?
2020
This paper engages critically with Dimitri Gutas’ recent characterization of post-classical Islamic philosophy and theology as a form of paraphilosophy or intellectual activity that merely simulates philosophy. I argue that this view arises from a misguided understanding of the concept of philosophy that should provide the standard for its historiography. In order to avoid a number of problematic consequences, such as gaps in historical continuity or a disconnection from what we understand by philosophy today, we must take our cue from a sufficiently uncontroversial contemporary concept of philosophy instead of any particular historical concept, such as the Peripatetic amalgam of metaphysic…
Discrete exterior calculus for photonic crystal waveguides
2022
The discrete exterior calculus (DEC) is very promising, though not yet widely used, discretization method for photonic crystal (PC) waveguides. It can be seen as a generalization of the finite difference time domain (FDTD) method. The DEC enables efficient time evolution by construction and fits well for nonhomogeneous computational domains and obstacles of curved surfaces. These properties are typically present in applications of PC waveguides that are constructed as periodic structures of inhomogeneities in a computational domain. We present a two-dimensional DEC discretization for PC waveguides and demonstrate it with a selection of numerical experiments typical in the application area. …
Ratures fécondes
2012
Commenting on daily life of the scientific community, newspapers highlight some characteristics of the way sciences are evolving, thanks to a kind of epistemological flash-back : the way they lean on working hypothesis, these working hypothesis leaning themselves on on-going dogma. These comments on scientific current affairs call for a new understanding of gradual corrections of hypothesis.
Regularization Preserving Localization of Close Edges
2007
International audience; In this letter, we address the problem of the influence of neighbor edges and their effect on the edge delocalization while extracting a neighbor contour by a derivative approach. The properties to be fulfilled by the regularization operators to minimize or suppress this side effect are deduced, and the best detectors are pointed out. The study is carried out in 1-D for discrete signal. We show that among the derivative filters, one of them can correctly detect our model edges without being influenced by a neighboring transition, whatever their separation distance is and their respective amplitude is. A model of contour and close transitions is presented and used through…
Natural induction: An objective bayesian approach
2009
The statistical analysis of a sample taken from a finite population is a classic problem for which no generally accepted objective Bayesian results seem to exist. Bayesian solutions to this problem may be very sensitive to the choice of the prior, and there is no consensus as to the appropriate prior to use.
Trastornos del habla en el síndrome X frágil. Una revisión bibliográfica.
2019
espanolEl sindrome X fragil (SXF) es un trastorno genetico causante de discapacidad intelectual hereditaria. Su prevalencia es mayor en los hombres. En este articulo se presenta una revision bibliografica para analizar por una parte su grado de afectacion linguistica y por otra la efectividad de su evaluacion o intervencion. A partir de determinados criterios de inclusion y exclusion, se ha analizado 19 articulos cuyos resultados han mostrado una variabilidad dependiente de los instrumentos aplicados, siendo especialmente eficaces los basados en el lenguaje guiado. Por tanto, se podria extraer conclusiones favorables a la hora de establecer en un futuro programas de evaluacion o intervencio…
Solving a model for the evolution of smoking habit in Spain with homotopy analysis method
2013
We obtain an approximated analytical solution for a dynamic model for the prevalence of the smoking habit in a constant population but with equal and different from zero birth and death rates. This model has been successfully used to explain the evolution of the smoking habit in Spain. By means of the Homotopy Analysis Method, we obtain an analytic expression in powers of time t which reproduces the correct solution for a certain range of time. To enlarge the domain of convergence we have applied the so-called optimal convergence-control parameter technique and the homotopy-Padé technique. We present and discuss graphical results for our solutions. ©
Principal Component and Neural Network Analyses of Face Images: What Can Be Generalized in Gender Classification?
1998
We present an overview of the major findings of the principal component analysis (pca) approach to facial analysis. In a neural network or connectionist framework, this approach is known as the linear autoassociator approach. Faces are represented as a weighted sum of macrofeatures (eigenvectors or eigenfaces) extracted from a cross-product matrix of face images. Using gender categorization as an illustration, we analyze the robustness of this type of facial representation. We show that eigenvectors representing general categorical information can be estimated using a very small set of faces and that the information they convey is generalizable to new faces of the same population and to a l…