A Novel Image Encryption Scheme Based on a Generalized Chinese Remainder Theorem

by Sergio Duarte Torres, David Becerra Romero, Luis Niño and Yoan Pinzon.

In this paper, a novel method for image encryption based on a Generalized Chinese Remainder Theorem (GCRT) is presented. The proposed method is based on the work developed by Jagannathan et al. Some modifications are proposed in order to increase the method’s encryption quality and its robustness against attacks. Specifically, the inclusion of a vector to reduce the segment pixel space and a Generalized Chinese Remainder Theorem (GCRT) algorithm are proposed. These vectors are generated randomly which allows its use as private keys joining these unrestricted key values generated by the GCRT algorithm. An analysis to study a system where the RGB channels are independently encrypted is performed. Some experiments were carried out to validate the proposed model obtaining very promising results. Read the paper.

A Model for Resource Assignment to Transit Routes in Bogota Transportation System Transmilenio

by Sergio Duarte Torres, David Becerra Romero and Luis Niño.

In this work, a model based on genetic algorithms, queue theory and graph theory for route planning in a mass transportation system is presented. Most important features of the proposed approach are i) the modeling of the Americas line in the mass transportation system Transmilenio in Bogota; ii) Data preprocessing using graph theory to characterize the shortest routes between all the possible combinations of destination and source stations; iii) the optimization of travel time by route assignment using genetic algorithms iv) the simulation of events using the Poisson and Erlang distributions, corresponding to bus arrival at specific stations and to users waiting time. An experimental methodology was developed to validate the proposed approach. Read the paper (In Spanish).