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Infection parameters of Heterorhabditis amazonensis (Nematoda: Heterorhabditidae) in different stages of Hibiscus pink mealybug
(2020)
The pink hibiscus mealybug Maconellicoccus hirsutus (Hemiptera: Pseudococcidae) is an invasive pest of an enormous variety of crops and has become a concern in many parts of the world. Early attempts to control M. hirsutus ...
Instrument for selecting and evaluating suppliers in small and medium-sized metalworking enterprises in Cartagena, Colombia
(2020)
The objective of this investigation is the definition of a practical tool that helps to improve the selection process and evaluation of suppliers in small and medium-sized metalworking enterprises in Cartagena city. For ...
Hybrid calibration procedure for fringe projection profilometry based on stereo vision and polynomial fitting
(2020-03-19)
The key to accurate 3D shape measurement in fringe projection profilometry (FPP) is the proper calibration of the measurement system. Current calibration techniques rely on phase-coordinate mapping (PCM) or back-projection ...
Mathematical modeling of a system composed of parabolic trough solar collectors integrated with a hydraulic energy storage system
(2020)
In this work we propose to model a 7.5 kWe power generation system, implementing a Parabolic Trough Collector system, coupled to an Organic Rankine Cycle (PTC/ORC) and a bladder-type hydraulic accumulator system. The purpose ...
Principales dificultades del alumnado universitario novel a la hora de elaborar un texto científico
(2020-05-14)
El presente trabajo de investigación-acción es un análisis mixto de corte descriptivo de los errores de micro-redacción, macro-redacción, metodológicos y de escritura en una presentación pública cometidos por 46 estudiantes ...
Optimal selection and location of fixed-step capacitor banks in distribution networks using a discrete version of the vortex search algorithm
(2020-09-19)
This paper deals with the problem of the optimal selection of capacitor banks in electrical AC distribution systems for minimizing the costs of energy losses during a year of operation through a discrete version of the ...
Alternatives for recovering the ecosystem services and resilience of the Salamanca Island Natural Park, Colombia
(2020-05-25)
From a comprehensive diagnosis of the associated basins, islands, and wetlands of the coastal lagoon system of Ciénaga Grande de Santa Marta, Colombia, this work describes feasible options for the recovery of its ecosystem’s ...
On the efficiency in electrical networks with ac and dc operation technologies: A comparative study at the distribution stage
(2020-08-20)
This research deals with the efficiency comparison between AC and DC distribution networks that can provide electricity to rural and urban areas from the point of view of grid energy losses and greenhouse gas emissions ...
Second-order cone approximation for voltage stability analysis in direct-current networks
(2020-09-24)
In this study, the voltage stability margin for direct current (DC) networks in the presence of constant power loads is analyzed using a proposed convex mathematical reformulation. This convex model is developed by employing ...
Predictive Analysis and Data Visualization Approach for Decision Processes in Marketing Strategies: A Case of Study
(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 ...
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.