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Mostrando ítems 1049-1068 de 1389
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Polylactic acid effectively reinforced with reduced graphitic oxide
(Cartagena de Indias, 2022-09-01)The present study was developed to reinforce a thermoplastic matrix with carbonaceous material to improve its thermal and mechanical properties. Composite materials formed from the homogenization of polylactic acid (PLA) ... -
Positioning and status of the Spanish numismatic journals in scientific databases
(Cartagena de Indias, 2019)The following article captures the current situation of the Spanish scientific journals focused on numismatics and their positioning in the main international bibliographical (Latindex, Web of Science and Scopus) and Spanish ... -
Potential dividends and actual cash flows in equity valuation. A critical analysis
(Cartagena de Indias, 2009-11-11)Practitioners and most academics in valuation include changes in liquid assets (potential dividends) in the cash flows. This widespread and wrong practice is inconsistent with basic finance theory. We present economic, ... -
Potential dividends and actual cash flows.A regional Latin American analysis
(Cartagena de Indias, 2009-11-26)We examine the value market assigns to components of the cash flow to equity including potential dividends. We study non financial publicly traded firms from five Latin American countries. The model includes four variables: ... -
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 ... -
Power flow approximation for DC networks with constant power loads via logarithmic transform of voltage magnitudes
(Elsevier Ltd, 2019)This paper proposes a logarithmic transformation of voltages (LTVM) for the power flow in DC grids. This problem is non-linear due to the presence of constant power loads (CPLs), which also introduce a negative resistance ... -
Power Flow in Bipolar DC Distribution Networks Considering Current Limits
(Cartagena de Indias, 2022-09)Power electronics converters are equipped with current controls that protect the converter from over-currents. This protection introduces non-differentiable equations into the power flow problem. The conventional Newton's ... -
Power flow methods used in AC distribution networks: An analysis of convergence and processing times in radial and meshed grid configurations
(Cartagena de IndiasCampus Tecnológico, 2023-01-23)The load flow problem (LFP) in power distribution networks allows us to find the nodal voltage values within the electrical systems. These values, along with the system parameters, are useful to identify the (technical,economic, ... -
Power flow solution in direct current grids using the linear conjugate gradient approach
(Cartagena de Indias, 2019-09-24)The Colombian power system is being modified by the large-scale integration of renewable energy resources and energy storage systems, in conjunction with the microgrid concept that originates the possibility of alternating ... -
Power monitoring based on industrial internet of things
(Springer Verlag, 2017)Monitoring has always been of crucial importance for industries, and it has been useful when getting notifications about critical parameters reaching threshold and alerts pertaining to failure of a specific device becomes ... -
Power quality detection and classification using wavelet and support vector machine
(Cartagena de Indias, 2019-09-24)This work presents the identification and classification of various disturbances that affect the quality of energy, seen as the quality of the voltage wave (harmonics, sag, swell and flicker). For this, the wavelet transform ... -
Prediction of motorcyclist traffic crashes in Cartagena (Colombia): development of a safety performance function
(Cartagena de Indias, 2021-04-05)Motorcyclists account for more than 380 000 deaths annually worldwide from road tra c accidents. Motorcyclists are the most vulnerable road users worldwide to road safety (28% of global fatalities), together with cyclists ... -
Prediction of particle level behavior in atmospheric air based on laws of physics of motion and geographic interpolation
(Cartagena de Indias, 2020)Given the global problem of high levels of pollutants in the atmosphere, it is essential to use tools to measure and determine these levels. Unfortunately, it is impossible to have devices that allow direct pollutants' ... -
Prediction of RFID performance in supply chains
(2010)This paper discusses the challenges to wide-spread radio frequency identification (RFID) adoption in supply chains using the technology s-curve and the concept of buying hierarchy. A survey on RFID uptake in New Zealand ... -
Predictive Analysis and Data Visualization Approach for Decision Processes in Marketing Strategies: A Case of Study
(Cartagena de Indias, 2020-10-08)In this paper, we perform a new strategy for recommender systems in online entertainment platforms. As a case of study, we analyzed the reading preferences based on users of Goodreads, a social network for readers, to ... -
Predictive power control for electric vehicle charging applications
(Cartagena de Indias, 2020-12-01)This paper presents a direct predictive power control (DPPC) design for vehicle charging applications. The proposed control design allows working in the Park's reference frame avoiding the usage of the phase-lock loops, ... -
Preface
(Springer Verlag, 2018) -
Preliminary Characterization of Chromium (VI) Solution Adsorption with Mytella charruana in Semi-Artificial Environments
(Springer, 2020)The bivalve specie Mytella charruana has shown great potential as a bioindicator in natural waters and a biofilter for the adsorption of metals, such as Cr(VI). This species has been found in important densities in Cartagena ... -
Preliminary machine learning model for citrus greening disease (Huanglongbing-HLB) prediction in Colombia
(Cartagena de Indias, 2020-11-09)Citrus greening disease (Huanglongbing-HLB) is considered the most destructive citrus disease worldwide. Of the three species of Candidatus liberibacter associated with HLB, two have been recently reported in Latin America. ... -
Presence of perchlorate in marine sediments from Antarctica during 2017–2020
(Cartagena de Indias, 2022-01-17)Perchlorate of natural origin is a persistent pollutant that affects thyroid function by inhibiting iodine uptake, and this pollutant is frequently detected in different ecosystems at concentrations that can harm human ...
Universidad Tecnológica de Bolívar - 2017 Institución de Educación Superior sujeta a inspección y vigilancia por el Ministerio de Educación Nacional. Resolución No 961 del 26 de octubre de 1970 a través de la cual la Gobernación de Bolívar otorga la Personería Jurídica a la Universidad Tecnológica de Bolívar.