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Waste heat is a widely available but little used source of power. Converting a thermal gradient into electricity is conventionally done using the Seebeck effect, but devices that use this effect are naturally inefficient. An alternate approach uses microelectromechanical systems (MEMS) to generate movement and time-varying temperature from a constant temperature gradient. Ferroelectric materials can...
The resonance properties of the metasurface were obtained using the pseudo-spectral time domain method. The frequency dependence of transmission and absorption of sub-THz waves passed through metasurface have been measured.
This paper presents a sliding mode control strategy for a Hybrid Energy Storage System (HESS) with a semi-active capacitor configuration, applied to electric vehicles. The system consists of a battery bank and ultracapacitor (UC) connected through a high efficiency DC-DC converter which controls the energy exchange with the rest of the system. The aim of HESS is to provide the power demand to the...
Gamification tools, including mechanics, dynamics and components, can be used to drive user's engagement in an evaluation process for a specific role. Competence's defined in a specific scale can measure the match in between the candidate's profile and the required position. This document explores a structured methodology in an online platform.
Learning assessment of engineering programs is a central aspect to consider when trying to improve the training of the future engineer. A group of teachers of mathematics area started a study on the proposed assessment plan. The process of aligning the course's objectives with the desired professional profile, teaching and assessment strategies led us to incorporate as a general objective: “students...
Understanding and modelling the mechanical behaviour of the aorta is a problem being treated since several decades ago. Usually, it is assumed that the viscoelastic properties of the aorta gradually change from the heart towards periphery, going from mainly elastic to more viscous vessels. This behaviour might be associated with the gradual diminution of the elastin/collagen ratio and the increase...
This work presents the theoretical analysis of the effects of dielectric relaxation on the response of polymer piezoelectric sensors. In systems that obtain spatial information from temporal signals, such as optoacoustic tomography, the accurate characterization of transducers is very important. There are many works in the literature about reconstruction algorithms assuming ideal piezoelectric sensors...
This work propose a simple and effective methodology to detect and estimate musical tones, in real time, from mid-register musical instrument executions. Digital signal processing not only involves time-frequency estimation algorithms to establish the executed tones but the capability to generate automatically the coding needed to adapt the information to MIDI protocol, a widely accepted standard...
A control strategy for LCL Grid-connected voltage source converters is proposed. With only grid feedback current control, the proposal allows the use of the proportional plus resonant regulator (PR) optimal design, regardless of the filter resonant frequency. To prove its feasibility, the controller is simulated in a realistic system for different values of resonant frequency. In addition, its superiority...
In the last few years, new requirements for induction motors efficiency have been imposed Therefore electrical machines manufacturers have had to redefine their design criteria in order to reduce the losses level with the aim to achieve efficiency values established by the IE2 and IE3 categories of the International Electrotechnical Commission (IEC). Given that, in the near future, is expected to...
The Soccer League Competition algorithm is a recently new approach to solve optimization problems using metaheuristic technique. It is based in the interaction between soccer players and teams, and the primary objective to win each match and become the best team player or league player. The present paper intends the Python programmatic implementation of Soccer League Competition to solve the Set Covering...
The government of Ecuador there has managed a model of development that it values to all his cultures, his idiosyncrasy and his natural environments, beside managing, across the National System of Protected Areas (SNAP), to implement actions in benefit of the conservation of the natural resources since it has happened in the National Parks. Likewise, other relevant progresses that have to be considered...
A nonogram corresponds to a puzzle game. The aim in this game is generating an image on a grid by checking certain cells, this cells have to satisfy some rules associated with each row and column. In this paper, genetic algorithms are used to solve this problem, applying certain improvements that will benefit the process of seeking solutions.
The weight of the chaotic non-linear dynamical systems is increasingly more important in sectors such as sciences, engineering, health, and, even, economy. This fact pushes the educative community toward the challenge of designing learning methodologies which enables to understand of the chaotic phenomenon. In this paper we propose an educative software application, easily accessible for medium level...
The crowdfunding has become a tangible alternative to the film industry in many countries, especially since 2009, the year in which the first specialized websites are born in this funding strategy. The network has made it possible through these platforms and the potential contributions of social networks, a creative one can be able to open to collective collaboration phase of audiovisual production,...
Technology projects, including the introduction of new systems such as CRMs and ERPs, have an impact on peoples emotions, perceptions and performance, as well as on organizational and company culture. They also tend to raise a series of management issues that are seldom addressed, causing many technology projects to fail. Technology managers must learn how to manage those changes associated with the...
The general object of this research, exploratory in nature, to analyze the main factors influencing female entrepreneurship, through religious tourism in Ecuador. The empirical research used logistic regression models (Logit), information obtained through surveys of a sample of women entrepreneurs in business lines related to: relics, handicrafts, textiles, candles, hotels, gastronomy, tour operators,...
Current TSV integration schemes include via-first, via-middle and via-last process flows. In this paper, a low thermal budget, 10ìm pitch and aspect ratio 10 (5ìm diameter, 50ìm depth) via-last TSV module is presented. The proposed via-last module is plugged in after the thinning module, with 50ìm thinned device wafers temporary bonded to a Si carrier, using Brewer Science Zonebond® material. After...
In this paper the linear temperature coefficient of frequency in bulk-extensional MEMS resonators is reduced utilizing a relatively thin layer of sputtered Fluorine-doped silicon dioxide (SIOF). The Fluorine doping is achieved through addition of a Fluorine-containing gas in the Ar/O2 gas mixture of a typical SiO2 RF magnetron sputtering process. Our preliminary results indicate that the temperature...
The relentless shrinking of microelectronic devices makes thermal management an increasingly important topic. To this end, we have developed a computational approach, which allows the prediction of heat flux in nanostructures based on atomistic simulations. As prototypical system, we present results for a silicon — silicon dioxide nanostructure, with (a) abrupt interfaces, and (b) interfaces after...
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