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The effect of non-pharmacological interventions to contain the spread of SARS-CoV-2 have caused negative impacts, especially in education. Re-opening schools and universities is regarded as a high risk scenario. This paper seeks to understand, with the help of mathematical modeling, possible mechanisms through which the virus could spread in an academic environment and to quantify contagions attributable to participating in academic activities. To simulate the dynamics of contagion at the University, an agent-based mathematical model that incorporated stochastic differential equations was built using academic data for the University's 2020-2 semester. The model suggests that hybrid-attendance combined with epidemiological surveillance can produce very safe operating conditions without significantly contributing towards more COVID infections in the city of Bogotá. [ABSTRACT FROM AUTHOR]

The last stage of classical transport modelling, known as the sequential model of the four steps, estimates the flow pattern of the system. Then, in a post-processing phase all measures of system performance such as the level of service and externalities are estimated. This paper compares the estimated BPR and conical volume-delay with data taken in six multilane roads in Bogota, finding ranges of recommended function parameters values. We concluded that the values traditionally used for these functions are not the best for explaining the congestion that occurs in the environment studied. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology to enhance the estimation of parameter matrices in multivariate autoregressive models. It uses the Kalman filter and state space representation to improve the precision of parameter estimation, while maintaining a reduced computational burden. Two methods of covariance matrix adaptation are considered within the Kalman filter framework to improve the estimator convergence rate while preserving precision. The methodology is tested on simulated data, electroencephalographic recordings and performance. As a result, a reduction of the computational burden of up to 40% is achieved, but reconstruction error reaches as much as 3%. [ABSTRACT FROM AUTHOR]

This paper presents a vibration based fuzzy classifier used to detect fault conditions in bearings. The fuzzy knowledge foundation is obtained from the behavior of the vibration signal in presence of a fault condition in out-er race, inner race, cage and rolling element. The fuzzy system is implemented in Matlab® and it is validated in a vibration dedicate test bench used for research proposes. The system performance exhibits reliability and robustness in the fault detection in each experimental fault scenario. [ABSTRACT FROM AUTHOR]

This paper presents a mathematical model of the problem of the planning of systems of electrical distribution which considers the location and sizing of new feeders and substations, and the reconductorazing of existing feeders. The mathematical model used is of the type Lineal Mixed Integer Programming (LMIP) and to solve it, an algorithm of Branch and Bound is used. In order to test the proposed algorithm, the electrical system of the city of Pereira is used. [ABSTRACT FROM AUTHOR]

In this paper we present an algorithm of binary classification based on Support Vector Machines. It is combined with a modified Boosting algorithm. It run faster than the original SVM algorithm with a similar generalization error and equal complexity model but it has more compact representation. [ABSTRACT FROM AUTHOR]

Hybrid systems arise by the interaction between continuous dynamical systems and Discrete-event systems. This paper presents two modeling frameworks for this type of systems, in particular Mixed and Logical Dynamical (MLD) systems is explained. Then, model predictive control using MLD models is presented. The results are applied to a three-tank benchmark system as example. [ABSTRACT FROM AUTHOR]

This paper presents a rigorous mathematical method -created by the author- to calculate accurately the optimal size (or capacity) of an industrial plant while it is beeing planned and evaluated. Text-books on Proyect Evaluation, Financial Mathematics and connected subjects do not mention this method neither any othe for solving this important problem in Industrial Engineering. [ABSTRACT FROM AUTHOR]