622 research outputs found

    Diseño de tamaño de empaque y embalaje óptimo de productos de consumo masivo, por medio de algoritmos genéticos, teniendo en cuenta los costos logísticos de salida: caso de una empresa colombiana

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    Diseño del tamaño del empaque y embalaje para una línea de productos de características homogéneas, a fin de minimizar los costos logísticos de salida. Se realizaron dos métodos de solución: un modelo matemático y una herramienta metaheuristica. El modelo matemático nos arrojo una solución relajada, por medio del software Lp-Solve, lo cual da una aproximación a la situación actual de la empresa. Por otro lado, el modelo metaheuristico, nos arroja una solución optima para resolver el problema que presenta la empresa ABC, ya que el software utilizado, Microsoft Excel, permitió resolver el problema a gran escala, mientras que el software Lp-Solve, permitió una solución con un numero mínimo de candidatos (inner y outer packs) y con una respuesta ineficienteIngeniero (a) IndustrialPregrad

    Alumbrado exterior. Una merecida revisión

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    El día 1 de abril de 2009 entró en vigor el Reglamento de Eficiencia energética en las Instalaciones de Alumbrado Exterior y sus Instrucciones Técnicas Complementarias, denominadas ITC-EA R.D. 1890/2008, de 14 de noviembre). Este reglamento, complementario al REBT, asume como principales finalidades la mejora de la eficiencia y ahorro energético, la limitación de la contaminación Lumínica, y la reducción de luz intrusa o molesta. En el artículo que se reproduce a continuación, sus autores, los Arquitectos Técnicos Francisco José Gómez Jurado y Juan Carlos Camacho Vega, hacen “una merecida revisión” de los conceptos clave que definen la contaminación lumínica y resume las principales finalidades de este Reglamento, las instalaciones a las que le es de aplicación y la estructuración de las instrucciones ITC-EA

    Control of Bloat in Genetic Programming by Means of the Island Model

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    This paper presents a new proposal for reducing bloat in Genetic Programming. This proposal is based in a well-known parallel evolutionary model: the island model. We firstly describe the theoretical motivation for this new approach to the bloat problem, and then we present a set of experiments that gives us evidence of the findings extracted from the theory. The experiments have been performed on a representative problem extracted from the GP field: the even parity 5 problem. We analyse the evolution of bloat employing different settings for the parameters employed. The conclusion is that the Island Model helps to prevent the bloat phenomenon

    On the system performance of DFT-S-OFDM and CP-OFDM for 5G Uplink in mmWave band

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    Both conventional Cyclic Prefix Orthogonal Frequency Division Multiplexing (CP-OFDM) and Discrete Fourier Transform Spread OFDM (DFT-S-OFDM) have been adopted for their use in the Physical Uplink Shared Channel (PUSCH) in the 5G New Radio (NR) standard. While CP-OFDM can better exploit the frequency characteristics of the channel, DFTS-OFDM has the advantage of a lower peak-to-average power ratio (PAPR). Due to the interactions between PAPR and power amplifier (PA) non-linearity, users adopting DFT-S-OFDM waveform may benefit from a potentially higher PA efficiency and extend their coverage by increasing their transmit power. In this paper we study the uplink performance of both waveforms and their interaction with non-linear PA and uplink power control in the millimeter-wave (mmWave) band to determine their optimal operational range

    Applications of artificial intelligence in dentistry: A comprehensive review

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    This work was funded by the Spanish Ministry of Sciences, Innovation and Universities under Projects RTI2018-101674-B-I00 and PGC2018-101904-A-100, University of Granada project A.TEP. 280.UGR18, I+D+I Junta de Andalucia 2020 project P20-00200, and Fapergs/Capes do Brasil grant 19/25510000928-3. Funding for open-access charge: Universidad de Granada/CBUAObjective: To perform a comprehensive review of the use of artificial intelligence (AI) and machine learning (ML) in dentistry, providing the community with a broad insight on the different advances that these technologies and tools have produced, paying special attention to the area of esthetic dentistry and color research. Materials and methods: The comprehensive review was conducted in MEDLINE/ PubMed, Web of Science, and Scopus databases, for papers published in English language in the last 20 years. Results: Out of 3871 eligible papers, 120 were included for final appraisal. Study methodologies included deep learning (DL; n = 76), fuzzy logic (FL; n = 12), and other ML techniques (n = 32), which were mainly applied to disease identification, image segmentation, image correction, and biomimetic color analysis and modeling. Conclusions: The insight provided by the present work has reported outstanding results in the design of high-performance decision support systems for the aforementioned areas. The future of digital dentistry goes through the design of integrated approaches providing personalized treatments to patients. In addition, esthetic dentistry can benefit from those advances by developing models allowing a complete characterization of tooth color, enhancing the accuracy of dental restorations. Clinical significance: The use of AI and ML has an increasing impact on the dental profession and is complementing the development of digital technologies and tools, with a wide application in treatment planning and esthetic dentistry procedures.Spanish Ministry of Sciences, Innovation and Universities RTI2018-101674-B-I00 PGC2018-101904-A-100University of Granada project A.TEP. 280.UGR18Junta de Andalucia P20-00200Fapergs/Capes do Brasil grant 19/25510000928-3Universidad de Granada/CBU

    Polarimetric techniques for determining morphology and optical features of High Refractive Index dielectric nanoparticles size

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    The spectral evolution of the degree of linear polarization (PL) at a scattering angle of 90º is studied numerically for high refractive index (HRI) dielectric spherical nanoparticles. The behaviour of PL(90º) is analyzed as a function of the refractive index of the surrounding medium and the particle radius. We focus on the spectral region where both electric and magnetic resonances of order not higher than two are located for various semiconductor materials with low absorption. The spectral behavior of PL(90º) has only a small, linear dependence on nanoparticle size R. This weak dependence makes it experimentally feasible to perform real-time retrievals of both the refractive index of the external medium and the NP size R. From an industrial point of view, pure materials are nonrealistic, since they can only be provided under certain conditions. For this reason, we also study the effect of contaminants on the resonances of silicon NPs by considering the spectral evolution of PL(90º).This research was supported by MICINN (Spanish Ministry of Science and Innovation, project FIS2013-45854-P)

    Utilización de Internet para la enseñanza de sistemas digitales

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    Las nuevas tecnologías de la información y la comunicación han creado grandes expectativas en educación, pues permiten superar las limitaciones de tiempo y lugar, abaratando incluso los costes. Además, no debe olvidarse que los medios informáticos ofrecen una serie de características que favorecen el aprendizaje significativo a través de actividades de tipo interactivo. Por eso, nos parece importante su aplicación a la enseñanza de la Informática, y en particular de los sistemas digitales. En esta ponencia se presenta un sistema multimedia, basado en Internet, que se está desarrollando con el fin de aplicarlo a la docencia de sistemas digitales en la asignatura Fundamentos de Informática. La ponencia presenta una descripción general de dicho sistema, así como de las herramientas y métodos utilizados para su construcción

    Using linear polarization for sensing and monitoring nanoparticle purity

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    We analyze the effect of contaminants on the quadrupolar magnetic, dipolar electric and dipolar magnetic resonances of silicon nanoparticles (NPs) by considering the spectral evolution of the linear polarization degree at right angle scattering configuration, PL(90º). From an optical point of view, a decrease in the purity of silicon nanoparticles due to the presence of contaminants impacts the NP effective refractive index. We study this effect for a silicon nanosphere of radius 200 nm embedded in different media. The weakness of the resonances induced on the PL(90º) spectrum because of the lack of purity can be used to quantify the contamination of the material. In addition, it is shown that Kerker conditions also suffer from a spectral shift, which is quantified as a function of material purity.This research was supported by MICINN (Spanish Ministry of Science and Innovation, project FIS2013-45854-P)

    Optimization Algorithms for Large-Scale Real-World Instances of the Frequency Assignment Problem

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    Nowadays, mobile communications are experiencing a strong growth, being more and more indispensable. One of the key issues in the design of mobile networks is the Frequency Assignment Problem (FAP). This problem is crucial at present and will remain important in the foreseeable future. Real world instances of FAP typically involve very large networks, which can only be handled by heuristic methods. In the present work, we are interested in optimizing frequency assignments for problems described in a mathematical formalism that incorporates actual interference information, measured directly on the field, as is done in current GSM networks. To achieve this goal, a range of metaheuristics have been designed, adapted, and rigourously compared on two actual GSM networks modeled according to the latter formalism. In order to generate quickly and reliably high quality solutions, all metaheuristics combine their global search capabilities with a local-search method specially tailored for this domain. The experiments and statistical tests show that in general, all metaheuristics are able to improve upon results published in previous studies, but two of the metaheuristics emerge as the best performers: a population-based algorithm (Scatter Search) and a trajectory based (1+1) Evolutionary Algorithm. Finally, the analysis of the frequency plans obtained offers insight about how the interference cost is reduced in the optimal plans.Publicad

    Prevalence of Rotavirus Genogroup A and Norovirus Genogroup II in Bassaseachic Falls National Park Surface Waters in Chihuahua, Mexico

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    Abstract: In areas lacking potable water treatment, drinking contaminated water may represent a public health threat. In addition to enteropathogenic bacteria and parasites, fecal contamination in water environments is associated with the transmission of enteric viruses and other causal agents of infectious disease. Rotavirus and norovirus are the main enteric viral agents responsible for diarrheic outbreaks. The aim of the present study was to detect seasonal variation of rotavirus and norovirus in the surface water at Bassaseachic Falls National Park during 2013. Rivers and streams within and nearby this park were sampled once in each season during 2013. Viral concentration was carried out by a handmade filtration equipment, using a commercial electropositive membrane coupled with the virus absortion elution technique (VIRADEL©). Detection of rotavirus and norovirus was performed by SYBR Green reverse transcription-real time polymerase chain reaction (SYBR GREEN© RT-qPCR) analyses. Norovirus genogroup II was detected in samples collected in June and October 2013. Inthecaseofrotavirus,genogroupAwasdetectedinMarchandJune. Thepresenceofrotavirus and norovirus was related to viral acute diarrhea in children less than five years of age, who were inhabiting the sampled areas. This may indicates that the contaminated water was potentially a risk factor for regional diarrheic outbreaks. Keywords: norovirus; rotavirus; surface water; VIRADEL; virus detection; environmen
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