257 research outputs found
Linguistic perceptions of Irish English in nineteenth-century emigrant letters : a micro-perspective analysis of John Kerr's letters.
In this paper we look at the real voices of Irish English speakers in the nineteenth century. By turning to the Corpus of Irish English Correspondence (McCafferty & Amador-Moreno, 2012), we analyse the perceptions that letter writers had of their own language use. We apply a micro-perspective analysis to the language of John Kerr, an Irish emigrant to America, in his letters to his uncle James Graham of Newpark (Co. Antrim, N. Ireland). We examine Kerr’s incisive comment on language use alongside metacommentary found in different Late Modern works, including dictionaries, essays on Irish English, as well as contemporary fictional representations of the variety of English spoken in Ireland during this period. Through this small batch of letters, we explore how the real voices of Irish English speakers echoed an enregistered Irish repertoire that may have raised awareness shaping their perceptions of their own dialect
Ponderación ML de parámetros en un sistema de reconocimiento de palabras basado en CDHMM
Speech dynamic feature are routinely used in current speech recognition systems in combination with short-term (static) spectral features. The aim of this paper is to propose a method to automatically estimate the optimum ponderation of static and dynamic features in a speech recognition system. The recognition system considered in this paper is based on Continuous-Density Hidden Markov Modelling (CDHMM) widely used in speech recognition. Our approach consists basically in 1) adding two new parameters for each state of each model that weight both kinds of speech features, and 2) estimating those parameters by means of a Maximum Likelihood training. Experimental results in speaker independent digit recognition show an important increase of recognition accuracy.Peer ReviewedPostprint (published version
Value of Travel Time Savings for University Students and Preference Heterogeneity
This paper examines the sensitivity of value of travel time savings (VTTS) to assumptions on individual preferences in a random utility discrete choice framework. Preferences heterogeneity is incorporated by introducing random parameters and by interacting characteristics of travel modes with characteristics of the individual. The data set is a revealed preference survey on student travel mode choice. The results indicate that there is a systematic influence of gender on VTTS and additional heterogeneity is explained by unobserved characteristics. The evidence also suggests model specifications that impose preferences homogeneity tend to produce lower estimates of VTTS compared with more flexible structures that allow random variation of parameters over individuals. However, the degree of underestimation seems to be context dependent..Random utility discrete choice models, preference heterogeneity, subjective value of travel time, random parameter logit.
Innovative concepts of Integrated Solar Combined Cycles (ISCC) using a Solid Oxide Fuel Cell (SOFC)
Concentrating Solar Power (CSP) is one of the most promising ways for electricity production of the upcoming years with high penetration of intermittent renewable energy sources such as wind and solar-photovoltaics. This is due to the fact that CSP when coupled to Thermal Energy Storage (TES) system enables large, inexpensive and flexible energy dispatch, which contributes to energy grid stabilization. At the same time, TES allows for steady operation of the power block by reducing undesirable fluctuations due to weather transient conditions and increasing the number of hours that the power block operates at design conditions 1. Despite the abovementioned advantages of CSP systems, a step further is needed for increase overall system efficiency and decrease CO2 emissions. Several studies have been performed considering high efficiency plant layouts such as combined cycle. For the latter, several works have been investigated about solar integration of combined cycle using parabolic trough and solar tower technologies. In both cases, solar energy was used for water/steam preheating and evaporation steps of the Rankine cycle in combination with the exhaust gases of fossil-fuel gas turbine engine. However, no research has been performed considering ISCC coupled with a Solid Oxide Fuel Cell (SOFC). In this research, two innovative layouts of ISCC power plants will be analyzed. First considers a ISCC based on solar tower and second a ISCC with a parabolic trough collector field coupled to the Heat Recovery Steam Generator (HRSG).
The objective of this research is analyze the energy behavior of both layouts, selecting the best ISCC scheme to be coupled with a SOFC. The simulations will be performed using Thermoflex software.
In both layouts, a SOFC is introduced before the combustion chamber at the topping cycle, and a Rankine cycle (bottoming cycle) with 2 pressures is considered.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
Spray Pyrolysis Processing for Optoelectronic Applications
Spray pyrolysis is a low-cost and simple technique for the fabrication of high-quality transparent and conducting oxide thin films for different optoelectronic applications. The fabrication method, structural, morphological, and electro-optical properties of fluorine-doped tin oxide (FTO) and tin-doped indium oxide (ITO) films have been investigated. The deposited films have low resistivity and high transparency. Applications of such films are shown in high-efficiency surface-barrier photodetectors and solar cells, where the films serve as an active and antireflection electrode. A short description of other undoped and doped oxide films such as ZnO and TiO2 fabricated by spray pyrolysis is presented
OptimizaciĂłn inspirada en la naturaleza y en la biologĂa: Lo bueno, lo malo, lo feo y lo esperanzador
Nowadays, optimization has become an important issue for industrial systems and product development. From an engineering perspective, optimization implies adjusting or fine-tuning system designs considering one or more performance factors. Unfortunately, for many complex problems there is no optimization technique that can achieve the optimum solution in a reasonable computation time. As a result, the optimization process is often done manually. In recent years a myriad of optimization techniques have appeared, all inspired by phenomena observed in nature, such as behavioral patterns in animals (such as the exploration and search for food, moving, hunting, …), physical and chemical processes [1]. These techniques, often referred to as nature- or bio-inspired optimization algorithms, allow users to optimize a problem without requiring special knowledge about it: they only need to be informed about the fitness function to be optimized, and the mechanisms by which new candidate solutions can be produced. Each algorithm defines how existing solutions can be combined and modified to create new ones in an intelligent way to search for the best solution. Although they cannot guarantee that the optimum solution will be eventually achieved, they can automatically yield good solutions in reasonable computation times. These features make bio-inspired optimization proposals a promising research area and a great alternative to optimize complex processes, as has been already showcased in many real-world problems. In this work we present nature- and bio-inspired optimization from a global perspective. We describe techniques falling in this area, their evolution, how they operate, and why they bridge an important gap not covered by previous optimization techniques. On a critical note, we also give a clear view of the current situation in the area, indicating the positive aspects and issues that should be urgently improved. Considering this critical view, we suggest promising trends that we believe will lead us to a brighter future in nature- and bio-inspired optimization, plenty of successful examples of their application to real-world engineering problems. The manuscript is structured as follows: Section 2 describes bio-inspired optimization and exposes the reasons and advantages that make this area interesting from the scientific and practical points of view (focusing on introducing what they are and why they are useful). In Section 3 we examine the exciting panorama of recent applications in which nature- and bio-inspired optimization has become a central technology (the good), the upsurge of novel metaphors for the design of new proposals that do not lead to innovative solutions (the bad), and poor methodological practices that draw misleading conclusions that must be avoided in this field (the ugly). Finally, Section 4 summarizes the paper and highlights what is next to be done in the area of bio-inspired optimization (the hopeful), especially for engineering applications
Lifting velocity predicts the maximum number of repetitions to failure with comparable accuracy during the Smith machine and free-weight prone bench pull exercises
This study compared the accuracy of the fastest mean velocity from set (MVfastest) to predict the
maximum number of repetitions to failure (RTF) between 2 variants of prone bench pull (PBP)
exercise (Smith machine and free-weight) and 3 methods (generalized, individualized multiplepoint,
and individualized 2-point). Twenty-three resistance-trained males randomly performed
2 sessions during Smith machine PBP and 2 sessions during free-weight PBP in different weeks.
The first weekly session determined the RTF-MVfastest relationships and subjects completed single
sets of repetitions to failure against 60-70-80-90%1RM. The second weekly session explored the
accuracy of RTFs prediction under fatigue conditions and subjects completed 2 sets of 65%1RM
and 2 sets of 85%1RM with 2 min of rest. The MVfastest associated with RTFs from 1 to 15 were
greater for Smith machine compared to free-weight PBP (F ≥ 42.9; P < 0.001) and for multiplepoint
compared to 2-point method (F ≥ 4.6; P ≤ 0.043). The errors when predicting RTFs did not
differ between methods and PBP variants, whereas all RTF-MVfastest relationships overestimated
the RTF under fatigue conditions. These results suggest that RTF–MVfastest relationships present
similar accuracy during Smith machine and free-weight PBP exercises and it should be constructed
under similar training conditions.The Biomedicine Doctoral Studies of the University of Granada, SpainSpanish Ministry of University
under a predoctoral grant (FPU19/01137)Spanish Ministry of Science and Innovation [PID2019-
110074GBI00/SRA/10.13039/501100011033)
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