Repositorio institucional - Concytec
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Laser spot measurement using simple devices
No full textThe authors gratefully acknowledge the Dirección de Gestión de la Investigación (DGI-PUCP) for funding under Grant No. DGI-2019-3-0044. C.S. acknowledges support from the Peruvian National Council for Science, Technology and Technological Innovation scholarship under Grant No. 236-2015-FONDECyT. We would also wish to thank R. Sanchez from the Applied Optics Group and the Quantum Optics Group for letting us use their lasers and equipment, as well as Y. Coello for the photodiode. We also thank J. A. Guerra for useful discussions and suggestions.We have designed and tested an automated simple setup for measuring the profile and spot size of a Gaussian laser beam, which exhibits a similar performance to ready-made optical devices, using three light sensors. We use a light dependent resistor as a novel instrument in this approach with good accuracy. We provide the setup in detail in order to be reproduced with the current technology at a standard laboratory. Two profiling techniques were implemented: the imaging technique for the CMOS 2D array (webcam) and scanning knife-edge-like technique using a single photodiode and a light dependent resistor. We apply up-to-date devices, such as a Raspberry Pi, for automation. The methods and sensors were compared to determine their accuracy using lasers of two different wavelengths and technologies. We verify that it is possible to use a webcam to determine the profile of a laser with 1% uncertainty on the beam waist, 1.5% error on the waistline position, and less than 3% error in determining the minimum spot radius. We show that it is possible to use a light dependent resistor to estimate the laser spot size with an 11% error. The photodiode measurement is the most stable since it is not affected by the change in laser intensity. © 2021 Author(s).Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
On the relevance of the metadata used in the semantic segmentation of indoor image spaces
No full textThis work has been partially funded by the Spanish Ministry of Sci-ence, Education and Universities, the European Regional DevelopmentFund and the State Research Agency [grant number RTI2018-098156-B-C52], and by FONDECYT / World Bank [grant number 026-2019FONDECYT-BM-INC.INV].The study of artificial learning processes in the area of computer vision context has mainly focused on achieving a fixed output target rather than on identifying the underlying processes as a means to develop solutions capable of performing as good as or better than the human brain. This work reviews the well-known segmentation efforts in computer vision. However, our primary focus is on the quantitative evaluation of the amount of contextual information provided to the neural network. In particular, the information used to mimic the tacit information that a human is capable of using, like a sense of unambiguous order and the capability of improving its estimation by complementing already learned information. Our results show that, after a set of pre and post-processing methods applied to both the training data and the neural network architecture, the predictions made were drastically closer to the expected output in comparison to the cases where no contextual additions were provided. Our results provide evidence that learning systems strongly rely on contextual information for the identification task process. © 2021 The Author(s)Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Phylogenomics reveals multiple introductions and early spread of SARS-CoV-2 into Peru
No full textWe are greatly grateful to all health personnel of Peru, especially to members of the Respiratory Virus Laboratory from NHI-Peru for their dedication in providing continued diagnostic and high-quality care during the pandemic. The authors would like to express our deep gratitude to Dr. Kelly Levano for his critical review of this manuscript. In addition, we wish to thank Guillermo Trujillo and members of the Respiratory Infectious Diseases Laboratory from NHI-Peru, especially Helen Horna and Liza Linares for their support for the Whole-Genome Sequencing. This work was supported by the National Institute of Health of Peru and the CONCYTEC-FONDECYT Program of Proyectos Especiales: Respuesta al COVID-19 2020-01-01 [grant number 034-2020-FONDECYT].Peru has become one of the countries with the highest mortality rates from the current coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To investigate early transmission events and the genomic diversity of SARS-CoV-2 isolates circulating in Peru in the early COVID-19 pandemic, we analyzed 3472 viral genomes, of which 149 were from Peru. Phylogenomic analysis revealed multiple and independent introductions of the virus likely from Europe and Asia and a high diversity of genetic lineages circulating in Peru. In addition, we found evidence for community-driven transmission of SARS-CoV-2 as suggested by clusters of related viruses found in patients living in different regions of Peru. © 2021 Wiley Periodicals LLCConsejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Postharvest freezing process assessment of the blueberry structure in three acts: Bioimpedance, color, and granulometry analysis
No full textThis research was funded by FONDECYT-CONCYTEC (grant contract number 271-2015-FONDECYT ), the São Paulo Research Foundation (FAPESP, Brazil) for funding the project N° 2018/05871-3 and CNPq proc . Num. 305295/2018-7 .The bioelectrical impedance, cell granulometry and the color of the freeze-thawed blueberries were investigated. The blueberries were subjected to freezing at −18 °C for 135 min, during this process, groups were removed to every 9 min, and stored at 4 °C until further analysis. Bioelectrical impedance, color, pH, total soluble solids and cell granulometry were measured. The characteristics of bioelectrical impedance, cell granulometry and color were analyzed by computational algorithms, which allowed extracting characteristic of blueberries during the freezing process. The results showed progressive loss of the cellular structure during freezing, this behavior was associated with the bioimpedance parameters. The cells damage also influenced color parameters, and cell granulometry. The color followed the direction toward darkness and more intense red-blue tones, which suggest the migration of pigments from the blueberry's skin towards the flesh. In conclusion, evaluation of the color and cell granulometry by computational algorithms with bioelectrical impedance provides a powerful tool for evaluating cell damage in blueberries during the freezing process. © 2021Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Potential antioxidant effect of fruit peels for human use from northern peru, compared by 5 different methods [Potencial efecto antioxidante de las cáscaras de frutas para uso humano del norte de perú, comparado por 5 métodos diferentes]
No full textThis research was funded by Fondo Nacional de Desarrollo Cient?fico, Tecnol?gico y de Innovaci?n Tecnol?gica (FONDECYT) del Consejo Nacional de Ciencia Tecnolog?a e Innovaci?n Tecnol?gica (CONCYTEC) del Gobierno de Per? (Convenio de Subvenci?n 153-2015-FONDECYT). The authors would like to thank Dr. Pedro Alva-Plasencia, principal researcher of the project PIC 06-2014, for providing the laboratory equipment.The objective of the work was to determine the antioxidant potential in vitro of freeze-dried peel extracts of 20 fruits from the northern region of Peru through five tests (Folin-Ciocalteu, DPPH., ABTS+., FRAP and CUPRAC). According to multivariate statistical analyzes, five groups were found: (i.) peel extracts with the highest values of antioxidant capacity (AC) from custard apple, and star fruit; (ii.) rind extracts with high AC values from quince, sweet granadilla, guava, and black grape; (iii.) husk extracts with middle values of AC from passion fruit, and red mombin; (iv.) shell extracts with low AC values from tangerine, mandarine, and bitter orange; and, (v.) coating extracts with the lowest AC values from pawpaw, red pawpaw, muskmelon, dragon fruit, yellow and red indian figs, pear, apple, and green grape. To conclude, the fruit lyophilized-husk extracts of custard apple, star fruit, quince, sweet granadilla, guava, and black grape obtained the best AC. © 2021, MS-Editions. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Terahertz Imaging and Machine Learning in the Classification of Coffee Beans
No full textAcknowledgments. P. Uceda and H. Yoshida acknowledge the financial support from Project Concytec – The World Bank “Mejoramiento y Ampliación de los Servicios del Sistema Nacional de Ciencia Tecnología e Innovación Tecnológica” 8682-PE through Fondecyt [contract no 006–2018].The geographical origin of coffee beans represents an effect on the attributes and quality of the product due to the different soil and weather conditions for a specific location. Therefore, the development of methods for rapid classification and authentication of coffee beans based on their geographical origin is essential. This research was done with the purpose of determining the capacity of coffee (Coffea arabica) varieties classification with the use of Terahertz (THz) imaging and machine learning. THz images of coffee beans samples from 3 different geographical origins were acquired with a time-domain spectrometer and then used to measure the classification performance of methods such as neural networks, random forests, and support vector machines. The results obtained reached an accuracy up to 91.2%, which showed that the use of THz imaging and machine learning is an effective method for the non-destructive analysis of coffee variables and classification based on geographical origin. © 2021, The Author(s), under exclusive license to Springer Nature Switzerland AG.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
La cuestión político-estratégica del Perú como objeto de producción y comunicación científica en el CAEN-EPG: el quehacer investigativo en seguridad, defensa y desarrollo
No full textPresenta una aproximación conceptual a lo político-estratégico del Perú, ya que este es el objeto de investigación académica e institucional en el CAEN-EPG, además de desprender los métodos y diseños de investigación para construir conocimiento científico sobre la situación de la seguridad, defensa y desarrollo nacional, y proponer algunos lineamientos para visibilizar la producción investigativa mediante un proceso de comunicación científica
Problemática y posibilidades de evaluación de los aprendizajes en la Educación Superior para la especialidad de Educación Inicial – Primaria
No full textContiene ensayos realizados por estudiantes en educación superior para la especialidad de educación inicial y primaria, quienes enfrentados a la situación de una educación virtual atípica proponen diversas maneras de evaluación para el nivel secundario
Lmc-complexity in Kronig-Penney model: Comparison of effects between structural and chemical disorder [Complejidad lmc en el modelo de Kronig-Penney: Comparación del efecto del desorden estructural y químico]
No full textC.V.L. y H.N. agradecen a FONDECYT (CONCYTEC) por el soporte financiero a trav?s del Programa ?Centros de Excelencia?.In this work we use the Kronig-Penney model with delta function potentials as a one dimensional model of solid in order to study the effects of structural and chemical disorder in the plane wave representation. Structural disorder takes into account the variation on the potential position and chemical disorder is produced by changing the potential intensity and keeping fixed the distance between potentials. LMC statistical complexity measure and electron flux are used to evaluate the disorder effects. Both of them, structural and chemical disorder, produce the maximization of the electron complexity and the minimization of the corresponding electron flux which indicates the inhibition of electron transport. © 2021, Universidad Nacional de Colombia. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Incentive-based conservation in Peru: Assessing the state of six ongoing PES and REDD+ initiatives
No full textIncentive-based conservation has gained ample notoriety over recent decades, particularly across Latin America where targeted incentives feature prominently in environmental services initiatives, such as for carbon storage or watershed regulation. Here we first develop an analytical framework for assessing the Peruvian initiatives of conservation incentives. We then identify six ongoing interventions that have introduced incentives conditional upon compliance with voluntary environmental commitments. We collected information from secondary sources and conducted semi-structured interviews with thirty national- and local-level stakeholders. We scrutinized the extent to which such initiatives featured impact-oriented design and implementation elements, as typically recommended in the state-of-the-art literature on Payment for Environmental Services (PES) and Reducing Emissions from Deforestation and forest Degradation (REDD+). We found only limited adoption of such recommendations, including spatial targeting, payment differentiation, enforced conditionality, and customized measures nurturing locally perceived equity and transparency. We argue, supported by a still incipient rigorous evidence from impact evaluations, that suboptimal design and implementation choices probably have influenced outcomes towards limiting the sought-for environmental and welfare impacts. We discuss three critical aspects for upscaling: overcoming financial and legal constraints, strategic involvement of non-government stakeholders, and more impact-oriented design of the interventions.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy