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Modelo de optimización y metaheurística para localizar centros de distribución de productos y su transporte usando ruteo de vehículos abierto en una red logística
No full textLa investigación bibliográfica realizada revela que existe preocupación en lo relacionado a la ubicación de los centros de distribución y el transporte sostenible de los productos hacia los clientes mediante vehículos apropiados para zonas urbanas, pues es necesario mantener un orden en las mismas y en consecuencia se preserva la salud y el medio ambiente urbano. Esto es posible si hacemos uso de los conocimientos computacionales aplicados en el contexto urbano. En este sentido la investigación realizada en esta tesis, considerando la complejidad del problema NP-completo, logro alcanzar el objetivo principal que fue desarrollar e implementar un modelo de optimización y una metaheurística basados en los paradigmas de algoritmos de programación lineal entera binaria y de aproximación, para viabilizar una red logística. Los resultados de las experiencias computacionales realizadas son alentadores los cuales pueden ser aplicados en diversas regiones sin necesidad de grandes cambios en el modelo propuesto y por tanto también en la metaheurística.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
PeruCRIS: A National Research Information Infrastructure based on DSpace-CRIS
No full textPeruCRIS es el proyecto peruano para la creación y operación de una Red Nacional de Información sobre Ciencia, Tecnología e Innovación Tecnológica. Se basa en software de código abierto y estándares abiertos, específicamente como una extensión de la red ya existente de repositorios peruanos de acceso abierto. La red está diseñada para ser interoperable con los sistemas CRIS y los repositorios de acceso abierto, y también para permitir el envío directo al eje central nacional (Plataforma PeruCRIS) de instituciones e investigadores. La Plataforma PeruCRIS va más allá de la simple agregación, apoyando la normalización de los datos, el enriquecimiento y la curación de los datos recopilados y la edición directa en los Directorios. Estos roles están reservados para el personal de Concytec y sirven como un medio para garantizar la integridad, precisión y calidad general de los datos. Un perfil CERIF particular y se está desarrollando un conjunto de vocabularios controlados para adaptarse a las necesidades particulares de información de alcance nacional. El lanzamiento parcial inicial de los directorios principales está programado para el segundo trimestre de 2021
New Ultrasound Telediagnostic System for Low-Resource Areas: Pilot Results From Peru
No full textWe thank Medical Imaging Ministries of the Americas and Medical Innovation and Technology for allowing the publication of their illustrated posters and videos as supplemental material; Pilar Stewart, Thomas Chaumont, Italo Fernandez Salgado, Silvina Zabala‐Travers, MD, Nicole Stephens, and Cheree Harlee, RDMS, for assistance in the study; Jane Lichorowic and Nadezhda Kiriyak for illustrating Figure 1; and Sarah Klingenberger for help with the figures. This work was supported by CONCYTEC/FONDECYT (175‐FONDECYT‐DE), Innovate Peru (596‐INNOVATEPERU‐EDAI‐2015 and PR‐PVE‐201), and the Pontificia Universidad Catolica del Peru (PUCP DGI‐2016‐345). Dr Castaneda and all authors affiliated with Medical Innovation and Technology have a financial stake in Medical Innovation and Technology, which seeks to deploy ultrasound in rural areas. All data analysis and manuscript writing were performed by the University of Rochester. The authors from Medical Innovation and Technology previewed the document, and any revisions were subject to approval from the University of Rochester and Medical Imaging Ministry of the Americas authors. This work was presented in part at the 2019 AIUM Annual Convention; April 6–10, 2019; Orlando, Florida.Billions of people around the world lack access to diagnostic imaging. To address this issue, we piloted a comprehensive ultrasound telediagnostic system, which uses ultrasound volume sweep imaging (VSI) acquisitions capable of being performed by operators without prior traditional ultrasound training and new telemedicine software capable of sending imaging acquisitions asynchronously over low Internet bandwidth for remote interpretation. The telediagnostic system was tested with obstetric, right upper quadrant abdominal, and thyroid volume sweep imaging protocols in Peru. Scans obtained by operators without prior ultrasound experience were sent for remote interpretation by specialists using the telemedicine platform. Scans obtained allowed visualization of the target region in 96% of cases with diagnostic imaging quality. This telediagnostic system shows promise in improving health care disparities in the developing world. © 2020 American Institute of Ultrasound in MedicineConsejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Spectral effects on the energy yield of various photovoltaic technologies in Lima (Peru)
No full textThis study presents for the first time the spectral impact on the performance of different photovoltaic (PV) technologies in Lima, Peru. We experimentally monitored the spectral distributions over one year (March 2019–February 2020). The average photon energy (APE) is calculated as a representative parameter to evaluate the spectral distributions. The spectral mismatch factor (MM) enables an estimation of the spectral gains of distinct PV technologies: amorphous silicon (a-Si), perovskite, cadmium telluride (CdTe), multicrystalline silicon (multi-Si), monocrystalline silicon (mono-Si) and copper indium gallium selenide with two distinct band-gaps (CIGS-1 and CIGS-2). We found that the annual APE has a value of 1.923 eV, indicating that the spectrum is shifted to shorter wavelengths. In contrast to studies performed in other locations, the spectral distribution shows relatively small monthly APE value variations. This nearly negligible seasonality could be attributed to the low latitude and the particular climate in Lima. Larger-bandgap PV technologies, such as a-Si, perovskite, and CdTe, resulted in annual spectral gains of +6.8%, +4.8%, and +2.1%, respectively. Lower-bandgap PV technologies (CIGS-2, multi-Si, CIGS-1, and mono-Si), present small annual spectral gains of ?0.9%, ?1.4%, ?1.6% and ?2.3%, respectively. Also, a quasi-linear correlation between APE and MM was found for all PV technologies. © 2021Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Advances and gaps in studies on healthy meat products and their relationship with regulations: The Brazilian scenario
No full textJuan D. Rios-Mera thanks the support of the Consejo Nacional de Ciencia, Tecnología e Innovacion ´ Tecnologica ´ - CONCYTEC from Peru (CIENCIACTIVA programme, PhD scholarship contract: No. 238-2018- FONDECYT).Background: Strategies for the reformulation of meat products respond to consumers’ demand for healthier food alternatives. The reduction of salt or sodium and animal fat, and the substitution of synthetic antioxidants by natural ones have been a subject of study for Brazilian researchers for many years, but the industrial application of new technological alternatives presents the challenge of adapting to regulations related to the processing of meat products. Scope and approach: Reports by Brazilian researchers from 2011 to 2019 were collected from the Scopus database and their abstracts were submitted to a textual analysis to visualize the trend of studies over these years. The relationship between the approaches/ingredients proposed in the studies and the Brazilian regulation was discussed. Key findings and conclusions: Numerous alternatives for natural antioxidants and salt and animal fat substitutes have been proposed, but Brazilian regulation is restrictive with respect to the use of natural antioxidants and the most studied salt substitute in meat products. However, studies using alternatives more compatible with Brazilian regulations have been proposed. For industrial application purposes, some flavorings and spices may have antioxidant activity and act as natural antioxidants, delaying the lipid oxidation of meat products; the sodium content can be reduced using several morphologies or sizes of salt particles; and the incorporation of oils rich in polyunsaturated fatty acids, embedded in oleogels and microparticles using encapsulating proteins, seem to be a viable alternative for reducing animal fat in meat products. © 2021 Elsevier LtdFondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Earthquake surface ruptures on the altiplano and geomorphological evidence of normal faulting in the December 2016 (Mw 6.1) Parina earthquake, Peru
No full textThe 2016 Mw 6.1 Parina earthquake ruptured a shallow-crustal normal fault within the high Andes of south Peru. We use high-resolution DEMs and field mapping of the surface ruptures generated by the earthquake, in combination with co-seismic and post-seismic InSAR measurements, to investigate how different features of the geomorphology at Parina are generated by the earthquake cycle on the Parina Fault. We systematically mapped 12 km of NW-SE trending surface ruptures with up to ~27 cm vertical displacement and ~25 cm tensional opening along strike, separated by a gap with no observable surface ruptures. Co- and post-seismic InSAR measurements require slip below this gap in surface ruptures, implying that surface offsets observed in paleoseismic trenches may not necessarily be representative of slip at seismogenic depths, and will typically yield an underestimate of paleo-earthquake magnitudes. The surface ruptures developed along 10–20 m high cumulative scarps cutting through late Quaternary fluvio-glacial deposits and bedrock. The 2016 Parina earthquake did not rupture the full length of the late Quaternary scarps, implying that the Parina Fault does not slip in characteristic, repeat earthquakes. At Parina, and across most of the Peruvian Altiplano, normal faults are most-easily identified from recent scarps cutting late Quaternary moraine crests. In regions where there are no recently-deposited moraines, faults are difficult to identify and lack time constraints to quantify rates of fault slip. For this reason, current fault maps may underestimate the seismic hazard in the Altiplano. © 2020Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Systematic study on the synthesis of novel ion-imprinted polymers based on rhodizonate for the highly selective removal of Pb(II)
No full textThe present work reports the successful synthesis of a novel Pb2+ ion-imprinted polymer (Pb-IIP) based on a rhodizonate-like selective ligand by precipitation. Three functional monomers, namely acid acrylic (ACRY), 2-acrylamido-2-methylpropane sulfonic acid (AMPSA) and allylamine (ALLY), were chosen by computer simulation using density functional theory (DFT). The materials obtained were applied for the selective removal of Pb2+ from aqueous solutions and were characterized by Fourier transform Infra-red (FTIR), scanning electronic microscopy (SEM) and flame atomic absorption spectrometry (FAAS). The results obtained from the adsorption experiments performed under optimal conditions were in good agreement with the computational design and showed that IIP-AMPSA exhibited a relatively higher adsorption capacity for Pb2+ (51.84 mg g?1) than IIP–ACRY (31.02 mg g?1) and IIP-ALLY (12.90 mg g?1). Kinetics studies showed that the adsorption process followed a pseudo second-order reaction rate, and equilibrium was reached after 10 min of reaction. The Temkin isotherm model was found to be the most appropriate for fitting the experimental data, indicating that the adsorption process occurred in the active centers with heterogeneous surface. Based on the application of IIP-AMPSA, the relative selectivity coefficients obtained for Pb2+ in the presence of Cu2+, Ni2+, Cd2+, Zn2+, Co2+, and Fe2+ were in the range of 89–128. The practical application of IIP-AMPSA showed that the recovery rate of Pb2+ from river samples was almost 100%; this can be attributed to the imprinted cavities and specific binding sites that were created, which, positioned in a predetermined orientation, formed a well-defined coordination geometry through the rhodizonate ligand. © 2020 Elsevier B.V.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Structural and magnetic properties of disordered crystalline Fe50Mn25+xSn25?x alloys with x =-1.25, 0.0, 2.5, 5.0, 7.5
No full textDisordered crystalline Fe50Mn25+xSn25?x alloys, with x =-1.25, 0.0, 2.5, 5.0, 7.5 (close to the full-Heusler alloys), were arc-melted in a high purity argon atmosphere and the molten pellets were individually sealed in quartz tubes also under argon atmosphere. Subsequently, they were annealed at 1173 K for 4 days, being finally quenched in a bath with cold water. Structural and magnetic properties have systematically been studied using X-ray diffraction,57Fe, and119Sn Mössbauer spectroscopies, and magnetization measurements recorded at room temperature. Rietveld refinement of the X-ray diffraction patterns of the annealed samples with x =-1.25 and 0 has revealed the presence of two hexagonal crystallographic phases: (i) a chemically disordered solid solution identified as ??(Fe/Mn)3Sn (majority fraction) and (ii) the ??Fe5Sn3 intermetallic compound (minority fraction). For samples with x = 2.5, 5.0, and 7.5, the Rietveld analysis has only indicated the presence of a chemically disordered solid solution identified as ??(Fe/Mn)3(Sn/Fe/Mn). Although compositions of the Fe50Mn25+xSn25?x alloys are close to that of full-Heusler alloys, none of them has the expected L21 structure. The average crystallite sizes, estimated from the Williamson-Hall method, are in the range of 256-62 nm. The average sizes has gradually decreased as the x-content is increased. Mössbauer results have shown localized-type magnetism from Fe non-equivalent sites, and itinerant-like magnetism on119Sn-probes. Magnetic hysteresis loops, recorded at 300 K for a maximum field of 2200 Oe, have indicated that the remanent and coercive fields have systematically decreased as the x-parameter has increased. Coercive fields are in the range for soft magnets (1-20 Oe). © 2021, Universidad Nacional de Colombia. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Enhancing carrot convective drying by combining ethanol and ultrasound as pre-treatments: Effect on product structure, quality, energy consumption, drying and rehydration kinetics
No full textUltrasound was combined with ethanol to improve different aspects of carrot convective drying, evaluating both processing and product quality. The ultrasound in water treatment resulted in cellular swelling and small impact on texture. Differently, the ultrasound in ethanol and ethanol treatments modified both carrot microstructure (cell wall modifications of parenchymatic tissue) and macrostructure (shrinkage and resistance to perforation). Pre-treatments with ultrasound in ethanol and ethanol improved the drying kinetics, reducing the processing time (similar to 50%) and the energy consumption (42-62%). These pre-treatments also enhanced rehydration, whose initial rate and water retention were higher than the control. In addition, the carotenoid content was preserved after drying, for all the treatments. Any impact on shrinkage was observed. A mechanistic discussion, based on structural modification (microstructure and macrostructure) and physical properties of water and ethanol, was provided. As conclusion, this work not only described positive aspects of combining the technologies of ultra sound and ethanol as pre-treatments to convective drying, but also proposed mechanisms to explain the phenomena.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Conferencia Virtual Internacional sobre Gestión de la Información en CTI 2021 [Brochure]
No full textContiene la programación, temas y datos de los expositores participantes en la Conferencia Virtual Internacional sobre Gestión de la Información en CTI 2021 realizada el 9 y 10 de setiembre del 2021