Variation propagation of bench vises in multi-stage machining processes

Comunicación presentada a MESIC 2019 8th Manufacturing Engineering Society International Conference (Madrid, 19-21 de Junio de 2019)Variation propagation has been successfully modeled by the Stream of Variation (SoV) approach in multistage machining processes. However, the SoV model basically supports 3-2-1 fixtures based on punctual locators and other workholding systems such as conventional vises are not considered yet. In this paper, the SoV model is expanded to include the fixture- and datum-induced variations on workholding devices such as bench vises. The model derivation is validated through assembly and machining simulations on Computer Aided Design software. The case study analyzed shows an average error of part quality prediction between the SoV model and the CAD simulations of 0.26%

Estimation of Total Phenols, Flavanols and Extractability of Phenolic Compounds in Grape Seeds Using Vibrational Spectroscopy and Chemometric Tools

Near infrared hyperspectral data were collected for 200 Syrah and Tempranillo grape seed samples. Next, a sample selection was carried out and the phenolic content of these samples was determined. Then, quantitative (modified partial least square regressions) and qualitative (K-means and lineal discriminant analyses) chemometric tools were applied to obtain the best models for predicting the reference parameters. Quantitative models developed for the prediction of total phenolic and flavanolic contents have been successfully developed with standard errors of prediction (SEP) in external validation similar to those previously reported. For these parameters, SEPs were respectively, 11.23 mg g−1 of grape seed, expressed as gallic acid equivalents and 4.85 mg g−1 of grape seed, expressed as catechin equivalents. The application of these models to the whole sample set (selected and non-selected samples) has allowed knowing the distributions of total phenolic and flavanolic contents in this set. Moreover, a discriminant function has been calculated and applied to know the phenolic extractability level of the samples. On average, this discrimination function has allowed a 76.92% of samples correctly classified according their extractability level. In this way, the bases for the control of grape seeds phenolic state from their near infrared spectra have been stablished.España MINECO AGL2017-84793-C2España, Universidad de Sevilla VPPI-II.2, VPPI-II.

Valorization of American Barrel-Shoot Wastes: Effect of Post Fermentative Addition and Readdition on Phenolic Composition and Chromatic Quality of Syrah Red Wines

The influence of post fermentative addition of American barrel-shoot wastes on phenolic composition and chromatic quality of Syrah red wines has been evaluated as an environmentally sustainable alternative to the conventional winemaking for avoiding the common color loss of red wines elaborated in warm climates. American oak wood byproducts added were previously classified by hyperspectral image analysis according to the amount of phenolic compounds transferred to the extraction media. After that, wines were elaborated under different maceration conditions by applying only one proportion of wood (12 g L−1) and two different maceration procedures (simple and double addition) and were compared with a traditionally macerated Syrah red wine (CW, no wood addition). Results proved the effectiveness of the moderate postfermentative addition of oak wood byproducts to stabilize the color of wines and to provoke lower color modification along the time, producing color wines chromatically more stable for a better aging. In the case of double addition, the adsorption of the pigments during the maceration presents a stronger effect on the color than copigmentation and polymerization by cause of the copigments extracted from the woodEspaña, Ministerio de Economía y Competitividad AGL2017-84793-C

Eficiencia de Tres Caldos Minerales en el Control de La Mancha Aceitosa (xanthomonas campestris) Antracnosis (colletotrichum gloeosporioides) y Mancha Ojo de Pollo (phomopsis ssp.) En Maracuya (passiflora edulis) en Santo Domingo de los Tsáchilas

La exportación de concentrado de maracuyá aportó 40 millones de dólares en el año 2003. Es una fruta de fácil preparación y representa un ingreso significativo para las familias del campo El incremento de las enfermedades en los cultivos de maracuyá especialmente (Phomopsis ssp, Xanthomonas campestris, Colletotrichum gloeosporioides), a llevado al uso indiscriminado de pesticidas, causando daños a la salud humana por las aplicaciones mal realizadas y residuos de estos en las frutas, contaminación del ambiente que incrementa los costos de producción resultando ser menos rentable la agricultura y provocando problemas sociales por la emigración de los campesino a las ciudades y en algunos casos a otros países. El propósito de brindar una alternativa encaminada a mejorar la calidad de producción, considerando que el cultivo de maracuyá es una de las frutas exóticas de exportación que genera divisas al país, que tiene el calificativo de producto estrella y que está considerado en el nuevo Sistema de Preferencias Generalizadas (SPG Plus), dado por la Unión Europea (Lideres; EL COMERCIO, 2005). Se desarrolló el presente proyecto de investigación orientado a contribuir con el mejoramiento del sector agrícola favoreciendo la conservación del medio ambiente utilizando fungicidas minerales no tóxicos que brinden eficiencia y rentabilidad. El objetivo general del trabajo fué: Comprobar la eficiencia y la rentabilidad de tres caldo minerales en el control de las enfermedades Mancha aceitosa (Xanthomonas campestris), Antracnosis (Colletotrichum gloeosporioides) y mancha ojo de pollo (Phomopsis spp.), en el cultivo de maracuyá. Los objetivos específicos planteados fueron: Determinar el mejor caldo mineral en el control de las enfermedades Mancha aceitosa (Xanthomonas campestris), Antracnosis (Colletotrichum gloeosporioides) y Mancha ojo de pollo (Phomopsis spp.), en el cultivo de maracuyá. Realizar el análisis económico del presupuesto parcial para los tratamientos evaluados. La hipótesis de investigación fue: Al menos uno de los caldos minerales, es eficiente y rentable en el control de Mancha aceitosa (Xanthomonas campestris), Antracnosis (Colletotrichum gloeosporioides) y Mancha ojo de pollo (Phomopsis spp.), en el cultivo de maracuyá

Millimeter wave band reconfigurable circuits (from 30 to above 100 GHz) in BiCMOS-MEMS technology

Nowadays, there has been an increased use of mobile devices and growth in the need for information, and because of this, wireless systems with higher data rates and wider bandwidths are demanded every year. Additionally, multi-applications systems need to operate at several frequency bands, which brings the need for compact frequency-reconfigurable devices. In order to offer solutions for the demands mentioned above, in this Thesis, compact frequency-reconfigurable low-noise amplifiers (LNAs) using RF-MEMS and HBT based switches for frequencies above 100 GHz are presented for the first time. Multimodal coupled microstrip and three-line microstrip (TLM) structures are implemented in the amplifier matching networks to achieve more-compact designs. To demonstrate the potentialities of the TLM structures, a novel compact multimodal TLM impedance tuner is presented. It features a Smith-chart impedance coverage of 70% in a large frequency bandwidth (1.4 to 3.2 GHz). The impedance tuner uses variable capacitors implemented with varactors to create asymmetries in the structure and interactions among the three-line microstrip modes. This results in an increase of the equivalent electrical size of the circuit thus reducing the overall physical size of the impedance tuner. Three frequency-reconfigurable D-band compact BiCMOS LNAs have been designed. The three designs consist of two cascode stages and were fabricated using a 0.13 µm SiGe:C BiCMOS process which includes an embedded RF-MEMS switch module. The first and second LNA designs operate at 125/140 GHz, while the third design operates at 125/143 GHz. The area of the designs is minimized by using only one RF-MEMS switch to select the frequency band and multimodal structures (a coupled microstrip structure and a TLM structure in the input matching networks of the first and third design respectively). A systematic design method to obtain balanced gain and noise figure for both frequency states is presented. An even more compact 120/140 GHz LNA design is accomplished by using an HBT-based switch instead of a RF-MEMS switch. It was fabricated with the same 0.13 µm SiGe:C BiCMOS process and using the same multimodal TLM structure in the input matching network as the third design mentioned above. The measurements of all the LNAs are in good agreement with the obtained simulations thus validating all the circuit designs and the systematic design method.Postprint (published version

Implementación de una solución sd-wan para el uso eficiente de los recursos de red en su aplicación en la Empresa Asertia en el año 2021.

El objetivo de esta investigación fue implementar una solución SD-WAN para el uso eficiente de recursos de red y control de accesos hacia aplicaciones corporativas e internet, inicialmente, se realizó un análisis de la red MPLS y sus riesgos informáticos, se evidenció que el acceso hacia los servicios corporativos que tiene Asertia de forma local en su oficina Matriz y en la nube a través de internet son afectados por la falta de control, esto conlleva a tener latencia con tiempos muy altos y gran cantidad de perdida de paquetes en la comunicación desde las sucursales a la Matriz e Internet que afecta económicamente a la empresa. Una vez ejecutada la implementación de SD-WAN, se aplicó pruebas para obtener la latencia y cantidad de paquetes perdidos y se analizó la información utilizando la prueba de U de Mann-Whitney para comprobar estadísticamente que existe una diferencia significativa en los escenarios de MPLS y SD-WAN. Los resultados obtenidos demuestran que la solución SD-WAN presenta mejoras considerables en valores de latencia y cantidad de paquetes perdidos y los riesgos informáticos se mitigaron a través del control de accesos hacia los servicios locales y en nube aplicando una conexión cifrada a través de VPN IPSec y aplicando los perfiles de seguridad perimetral como IPS, Antivirus, Sandboxing, Web Filtering y Application Control.The aim of this research was to implement an SD-WAN solution for the efficient use of network resources and access control to corporate applications and the Internet. Initially, an analysis of the MPLS network and its computer risks was carried out to demonstrate that the access towards the corporate services that Asertia has locally in its head office and in the cloud through the internet are affected by the lack of control. It leads to latency with very high times and a large amount of packet loss in the communication from the branches to the headquarters and the Internet that economically affects the company. Once the SD-WAN implementation was executed, tests were applied to obtain the latency and number of lost packets and this information was analyzed using the Mann-Whitney U test to statistically verify that there is a significant difference in the MPLS and MPLS scenarios and SD-WAN. The results obtained shown that the SD-WAN solution presents considerable improvements in latency values and the number of lost packets and computer risks were mitigated through access control to local and cloud services by applying an encrypted connection through IPSec VPN and applying perimeter security profiles such as IPS, Antivirus, Sandboxing, Web Filtering and Application Control

Physical impacts of mining on the hydrological environment

El presente TFM ha sido desarrollado en el contexto de una investigación exploratoria bibliográfica de tal manera de recopilar a través de diversas fuentes y datos públicos el estado del conocimiento de las afecciones al medio físico hidrológico debido a proyectos mineros y brinda al lector los elementos necesarios para el entendimiento de la problemática y plantea nuevos retos a los interesados en investigar las ciencias ambientales y de la tierra. Una de las premisas fundamentales al considerar la interacción del agua con las actividades mineras es el entender que las aguas superficiales como las subterráneas en conjunto, son un único recurso y que impactos negativos sobre cualquiera de estas, inevitablemente, generara efectos negativos sobre las otras. Los impactos físicos sobre el medio hidrológico se pueden resumir en: 1) alteraciones en la dinámica fluvial de los cuerpos superficiales locales y regionales, 2) perdidas de masas de agua y variaciones en el ciclo hidrológico y 3) alteraciones en el régimen hidrogeológico causante de variaciones de niveles de agua y fenómenos de subsidencia Las variaciones en la dinámica fluvial pueden deberse a los cambios en las tasas de sedimentación por erosión, los cambios en los trazados fluviales y variaciones de perfil. Las actividades de bombeo y dewatering para dar seguridad geotécnica y estabilidad estructural a los macizos sin duda causan variaciones, por un lado, se pueden crear conos de depresión pronunciados en la napa freática, reduciendo el nivel del agua subterránea, además de fenómenos de descompresión de acuífero que pueden traducirse en subsidencias y hundimientos. Actividades como modificación del relieve, remoción de la cobertura vegetal y compactación del terreno pueden provocar indirectamente disminuciones en la capacidad de infiltración disponible del suelo, alteraciones en la dinámica de la evapotranspiración, aumento de la escorrentia superficial, disminuciones en el contenido de humedad de los suelos entre otros. Las actividades mineras tienen la capacidad de desencadenar una serie de impactos físicos al recurso hídrico, incluso algunos de estos impactos pueden ser irreversibles y/o requerirán de tiempo y grandes esfuerzos para alcanzar el equilibrio hidrológico original.This TFM has been developed in the context of an exploratory bibliographic research to compile, through various sources and public data, the state of knowledge of the effects on the physical hydrological environment due to mining projects. This document provides the reader with the necessary elements to understand the problem and poses new challenges to researchers in environmental and earth sciences. One of the fundamental premises when considering the interaction between water and mining activities is to understand that both surface water and groundwater are a single resource and that a negative impact on any of these will inevitably generate negative effects on the others. The physical impacts on the hydrological environment can be summarized as: 1) alterations in the fluvial dynamics of local and regional surface bodies, 2) loss of water masses and variations in the hydrological cycle and 3) alterations in the hydrogeological regime causing variations in water levels and subsidence phenomena. Variations in fluvial dynamics may be due to changes in sedimentation rates due to erosion, changes in fluvial patterns and profile variations. Pumping and dewatering activities to provide geotechnical security and structural stability to the massifs undoubtedly cause variations; on the one hand, they can create pronounced cones of depression in the water table, reducing the groundwater level, in addition to aquifer decompression phenomena that can lead to subsidence and subsidence. Activities such as relief modification, removal of vegetation cover and soil compaction can indirectly cause a loss of soil infiltration capacity, alterations in the dynamics of evapotranspiration, increased surface runoff, decreases in soil moisture content, among others. Mining activities have the capacity to trigger a series of physical impacts on water resources, and some of these impacts may even be irreversible and/or require time and significant efforts to reach the original hydrological balance.Máster Universitario en Hidrología y Gestión de Recursos Hídricos (M174

Análisis comparativo sobre el desempeño de destrezas numéricas en niños y niñas del primero de básica en cuatro escuelas de la ciudad de Cuenca

Cimentar el desarrollo de bases matemáticas sólidas a temprana edad, representa un aspecto de éxito en la comprensión de temas matemáticos futuros por parte del niño. El dominio de las destrezas relacionadas con la adquisición de la competencia matemática, es primordial en la resolución de problemas, tanto a nivel matemático, como en otras áreas del conocimiento. El objetivo de la presente investigación fue realizar un estudio comparativo del desempeño numérico de los niños en las destrezas relacionales y del conteo, por medio de la aplicación del Test de Evaluación Matemática Temprana. Los participantes fueron niños y niñas del Primer Año de Básica de cuatro escuelas particularesde la ciudad de Cuenca. La edad media de los participantes fue de 5 años, 10 meses (DT=3,9 meses). Los resultados indicaron un desempeño superior de la muestra en la escala relacional en comparación con la escala del conteo. También, se confirmó la influencia de la edad en la adquisición de las destrezas; existiendo una excepción de esta influencia en una de las destrezas evaluadas.Building mathematical foundations at an early age will result in children`s better future mathematical achievements. The skills related to mathematical competence are central for problem solving, not only in mathematics but also in other areas. The aim of this research was to do a comparative study of the numerical performance of children in relational and counting skills through the application of the Utrecht Early Numeracy Test. The sample comes from the participation of students of the first year of basic education from four private schools in the city of Cuenca. The average age of the participants was 5 years plus 10 months old (SD = 3.9 months). The results from the sampleshow a superior performance in the relational skills in comparison with counting skills. The results also confirm the influence of the age on the acquisition of skills in general. An exception of this influence exists in one of the evaluated skills.Magíster en Educación y Dasarrollo del PensamientoCuenc

Compact, wideband impedance tuner using a three-line-microstrip structure

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.A novel three-line-microstrip compact impedance tuner is presented. It is based on a multimodal structure wherein six variable capacitances, implemented with two parallel-connected varactors each, create multiple interactions among the three-line-microstrip modes in a reduced circuit area. Experimental results show better-than-70% coverage of the Smith chart in an 85% frequency bandwidth from 1.4 to 3.2 GHz.Peer ReviewedPostprint (author's final draft

Optimal bidding strategies for thermal and generic programming units in the day-ahead electricity market

This paper develops a stochastic programming model that integrates the day-ahead optimal bidding problem with the most recent regulation rules of the Iberian Electricity Market (MIBEL) for bilateral contracts, with a special consideration for the new mechanism to balance the competition of the production market, namely virtual power plants auctions (VPP). The model allows a price-taker generation company to decide the unit commitment of the thermal units, the economic dispatch of the bilateral contracts between the thermal units and the generic programming unit (GPU) and the optimal sale/purchase bids for all units (thermal and generic) observing the MIBEL regulation. The uncertainty of the spot prices is represented through scenario sets built from the most recent real data using scenario reduction techniques. The model was solved with real data from a Spanish generation company and spot prices, and the results are reported and analyzed