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Trajectory Graphs Appearing from the Skein Problems at the Hypercube

Feliú Salgols, Guillermo Morales-Luna, Israel Buitrón-Dámaso
Artículo de revista Revista Computación y Sistemas, Vol. 20, No. 1 (2016).

Resumen

We formally state Skein Problems in Hamiltonian graphs and prove that they are reduced to the Independence Problem in Graph Theory. Skein problems can be widely used in cryptography, particularly, in protocols for message authentication or entities identification. Let G be a Hamiltonian graph. Given a Hamiltonian cycle H, let Π be a set of pairwise disjoint sub-paths within H, P1 = [v11, . . . , vm1], . . . , Pk = [v1k, . . . , vmk] where m and k are two positive integers, then the pairs of extreme vertices V = {(v11, vm1), . . . , (v1k, vmk)} are connected by the paths at Π without any crossing.

Conversely, let us assume that the following problem is posed: given a collection of pairs V it is required to find a collection of pairwise disjoint paths, without any crossing, connecting each pair at V. We reduce this last problem to the Independence Problem in Graph Theory. In particular, for the case of the n-dimensional hypercube, we show that the resulting translated instances are not Berge graphs, thus the most common polynomial-time algorithms to solve the translated problem do not apply. We have built a computing system to explicitly generate the resulting graphs of the reduction to the Independence problem. Nevertheless, due to the doubly exponential growth in terms of n of these graphs, the physical computational resources are quickly exhausted.

HTTPS connections over Android

Israel Buitron-Damaso, Guillermo Morales-Luna
Artículo de conferencia Electrical Engineering Computing Science and Automatic Control (CCE), 2011 8th International Conference on. IEEE, 2011.

Resumen

In this article we discuss a programming model to establish a secure communication channel by using HTTPS protocol in Android platform, using some public key infrastructure features like public keys and digital certificates.

Sistema de adquisición de datos con ancho de banda variable usando USB

Hugo, García Ortega Victor, Sosa Savedra Julio César, Hernández Mejía, Hernández Pacheco José Ricardo, and Buitrón Dámaso Israel
Artículo de conferencia

Resumen

Este articulo describe el diseño de un sistema de adquisición de datos que opera sobre un rango de frecuencia variable, con el fin de procesar diversas señales analógicas de forma digital haciendo uso de la interfaz de comunicación USB (Universal Serial Bus) hacia una PC, mostrando los resultados de un determinado procesamiento digital en pantalla. Se hace uso de diversos elementos de vanguardia respecto a hardware y software, entre ellos filtros con frecuencia de corte programable, microcontroladores, interfaz USB, CODEC para análisis de voz, así como un software desarrollado en un lenguaje de alto nivel y rendimiento, basado en el paradigma orientado a objetos.