Universidad Tecnológica de Bolivar UTB (Colombia): últimos ingresos
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Occurrence of personal care products as emerging chemicals of concern in water resources: A review
(Elsevier B.V., 2017)Personal care products (PCPs) are a diverse group of common household substances used for health, beauty and cleaning purposes. These include disinfectants, fragrances, insect repellents, preservatives and UV filters, among ... -
LFSR characteristic polynomial and phase shifter computation for two-dimensional test set generation
(Institute of Electrical and Electronics Engineers Inc., 2017)In built-in two-dimensional deterministic test pattern generation, a Linear Feedback Shift Register (LFSR) extended by phase shifters (PS) is commonly used for generating the test patterns. The specific LFSR/PS structure ... -
Differential diagnosis of dengue and chikungunya in colombian children using machine learning
(Springer Verlag, 2018)Dengue and chikungunya are vector borne diseases endemic in tropical countries around the world, with very similar clinical presentation, which makes it hard for physicians to tell them apart. Here we propose the use of ... -
Exact galactic disk-haloes model in Einstein-Maxwell gravity
(World Scientific Publishing Co. Pte. Ltd., 2018)An exact model in Einstein-Maxwell gravity describing a magnetized galactic disk-halo system is presented. The description of properties of the stationary metric and its source are discussed. All the expressions are presented ... -
Motion of test particles in a magnetized conformastatic background
(World Scientific Publishing Co. Pte. Ltd., 2018)A class of exact conformastatic solutions of the Einstein-Maxwell field equations is presented in which the gravitational and electromagnetic potentials are completely determined by a harmonic function only. The motion of ... -
Black hole-wormhole transition in (2+1)-dimensional Einstein-anti-de Sitter gravity coupled to nonlinear electrodynamics BLACK HOLE-WORMHOLE TRANSITION in (2+1)- ⋯ PEDRO CAÑATE and NORA BRETON
(American Physical Society, 2018)In this paper we present two results in (2+1) gravity coupled to nonlinear electrodynamics. First we determine the general form of the electromagnetic field tensor in (2+1) gravity coupled to nonlinear electrodynamics in ... -
Organizational cynicism - An exploration analysis-case: Workers in the city of Cartagena de Indias (Colombia)
(Revista Espacios, 2018)Organizational cynicism is a fact that is present and negative within organizations. In this sense, the present study aims to approach the phenomenon of cynicism in organizations from the study of cynical attitudes composed ... -
Wage and subjective conditions assessing tool applied for the quality of work: Case of the manufacturing sector of the Colombian Caribbean region
(International Business Information Management Association, IBIMA, 2018)Wage and Subjective Conditions Assessing Tool was designed and applied as a tool for assessing psychosocial components of job safety in a sample of 518 employees from different companies in the manufacturing sector of the ... -
Optimal power dispatch of DGS in DC power grids: A hybrid gauss-seidel-genetic-algorithm methodology for solving the OPF problem
(World Scientific and Engineering Academy and Society, 2018)This paper addresses the optimal power flow (OPF) problem in direct current (DC) power grids via a hybrid Gauss-Seidel-Genetic-Algorithm methodology through a master-slave optimization strategy. In the master stage, a ... -
Power Flow Analysis in DC Grids: Two Alternative Numerical Methods
(Institute of Electrical and Electronics Engineers Inc., 2019)This express brief proposes two new iterative approaches for solving the power flow problem in direct current networks as efficient alternatives to the classical Gauss-Seidel and Newton-Raphson methods. The first approach ... -
CFD and 1D simulation of transient flow effect on air vessel
(BHR Group Limited, 2018)The estimation of unsteady parameters in two-phase condition is crucial for the safety and reliability of the hydraulic systems. There are plenty of one-dimensional (1D) simulation tools for unsteady flow estimation being ... -
An automatic approach to generate corpus in Spanish
(Springer Verlag, 2018)A corpus is an indispensable linguistic resource for any application of natural language processing. Some corpora have been created manually or semi-automatically for a specific domain. In this paper, we present an automatic ... -
Influence of Arduino on the Development of Advanced Microcontrollers Courses
(Education Society of IEEE (Spanish Chapter), 2017)This paper describes the development of courses in the field of digital design that use Arduino boards as their main platforms. Arduino offers an intuitive development environment and multiple hardware and software resources ... -
A parametric sensitivity analysis of numerically modelled piston-type filling and emptying of an inclined pipeline with an air valve
(BHR Group Limited, 2018)Filling and emptying operations should be planned by engineers in operational stages to prevent a system failure depending on reaching extreme low pressure values. In this sense, a compression of an air pocket produces ... -
Distributed energy resources integration in single-phase microgrids: An application of IDA-PBC and PI-PBC approaches
(Elsevier Ltd, 2019)This paper presents a unified Hamiltonian formulation for controlling distributed energy resources (DERs)in ac single-phase microgrids (SP-MGs)via proportional-integral passivity-based control (PI-PBC), and interconnection ... -
Evaluating the influence of camera and projector lens distortion in 3D reconstruction quality for fringe projection profilometry
(OSA - The Optical Society, 2018)We study the influence of geometric distortions of the camera and projector lenses on 3D reconstruction quality for fringe projection profilometry. Experimental results on real objects and their 3D models show the accuracy ... -
Camera-projector calibration methods with compensation of geometric distortions in fringe projection profilometry: A comparative study
(Sociedad Espanola de Optica, 2018)The calibration methods most used in fringe projection profilometry are based on models of least squares adjustment and stereo vision techniques. However, the geometric distortions of the projector and camera lenses introduce ... -
Optimization of a drive shaft using PSO algorithm
(World Scientific and Engineering Academy and Society, 2018)Mechanical design involves several continuous variables associated with the calculation of elements that compose the parts implemented in different processes. However, when the values associated with several design variables ... -
Optimal Location of Protective Devices Using Multi-objective Approach
(Springer Verlag, 2018)In this paper a multi-objective model for the problem of optimal location of reclosers and fuses in power electric distribution systems is presented, considering the possibility of fuse rescue through the coordinated ... -
Hierarchical agglomerative clustering of time-warped series
(Springer Verlag, 2018)We have developed a procedure for hierarchical agglomerative clustering of time series data. To measure the dissimilarity between these data, we use classically the Euclidean distance or we apply the costs of the series ...