3,919 research outputs found
Performance Measurement Systems, Competitive Priorities, and Advanced Manufacturing Technologies: Some Evidence from the Aeronautical Sector
Purpose – When acquiring advanced manufacturing technologies (AMT), the greatest caution should be taken regarding the performance measurement system to be used: the decision regarding new investments should not be conditioned by the excessive use of financial indicators to the detriment of the strategic objectives that motivated the investments. It is intended to analyze the aeronautical sector, for which the purchase of AMT is qualifying criteria, with two intentions: first, to identify the performance measurement systems that are used, and second, to test their correspondence with the objectives that motivated the investments. Design/methodology/approach – A survey of the 20 plants in the population was conducted via a postal questionnaire plus a structured interview. The unit of analysis has been maintained through the triangulation of data sources. Findings – The findings suggest that both financial and non-financial indicators are used, with the latter gaining predominance over the former on some occasions, even though there is no clear correspondence between strategy and the measurement of performance. In the light of the findings, the question of what inspires a company’s performance measurement system is still open, especially in those cases where there is no explicit strategy. With regard to practical implications, what seems to be indispensable is an improvement in the determination of the critical variables that should be used to measure performance. Research limitations/implications – Being valuable for academics and practitioners, this contribution relies, rather, on the possibility of a logical extrapolation to circumstances where the findings might apply, and researchers can judge whether the particular findings would be valid. Originality/value – Provides new evidence on the adaptation of the make-up and combination of the type of performance measures currently used by plants in the aeronautical industry, one of the sectors in which technological innovation is of the utmost importance.Publicad
COSTES NORMALIZADOS Y COMPLETOS EN LA PRESTACIÓN DEL SERVICIO ELÉCTRICO, COMO HERRAMIENTA PARA LA TOMA DE DECISIONES EMPRESARIALES
El propósito del trabajo es abordar el cálculo de costes en las empresas eléctricas con fines de gestión interna. Para ello, se analizan las grandes fases que componen la cadena de valor en el sector eléctrico: generación, transmisión, distribución y comercialización de la energía eléctrica; se sugieren formas de superar las carencias detectadas y se muestran aplicaciones prácticas de laspropuestas. La metodología permite mostrar un cálculo del servicio por cada una de estas variables, para luego, aglutinar y mostrar los costes por Estado y actividad. Finalmente, se presenta un resumen del rendimiento operativo en ingresos y costes por servicio, oficina comercial, carga social asumida, entre otros. El trabajo aporta herramientas para reconocer estructuras departamentales que deben mejorar su rendimiento.Costes sector eléctrico, generación, transmisión, distribución, comercialización.
RANKING FINANCIERO: HERRAMIENTA FINANCIERA PARA MEDIR LA PRODUCTIVIDAD DE LAS EMPRESAS DE COMERCIALIZACIÓN DE ENERGÍA ELÉCTRICA
RESUMENLa investigación centra su atención en el diseño de una herramienta financierapara medir la productividad de las empresas de comercialización de energía partiendo del diagnóstico,estudio y determinación de las variables de productividad, así como razones financieras simplificadas y necesarias para su medición. Define un rango de productividad por estructuradepartamental y refleja las variables improductivas o de mejora continua. La novedad, en cuanto a las metas, es la reducción del riesgo financiero y la autogestión por estructuradepartamental. También determina la posición de cada ente y evalúa sus resultados en dos sentidos: en sentido horizontal el resultado de cada variable por estructura y, en sentido vertical, en comparación con las variables de las demás estructurasdepartamentales.Indicadores de productividad, rankingfinanciero, intervalo de eficiencia,variables de productividad.
Adopting and Implementing AMT: New Data on Key Factors from the Aeronautical Industry.
The objective of this paper is to take a greater in-depth look at which factors might be considered to be key to the performance of investments made in advanced manufacturing technologies (AMT), given their supposed positive effects, and on the influence that the time these factors are taken into account during the adoption and implementation process can have on that relationship. It provides a specially devised empirical analysis in the aeronautical sector in the south of Spain. A survey of the 20 plants in the population was conducted via a postal questionnaire between July 1999 and April 2001, with a structured interview being held at a later date. The testing of hypotheses was performed by applying the t-test to independent samples. The results show that the only factor that has a clear and positive effect on performance is the training of personnel. It can also be seen that a lack of strategic planning contributes to dampening the effects of investments. These results may be of some help to management staff and public administrators in charge of promoting the process of technological innovation, by indicating actions that need to be taken in order to successfully adopt and implement AMT.
Poblamiento y organización del espacio. La Tarraconense pirenaica en el siglo VI
ESPAÑOL: La donación y el testamento de Vicente de Asán, de los años 551 y 576 respectivamente, son dos documentos fundamentales para el conocimiento de la estructura de propiedad en el periodo visigodo. Estos documentos han sido objeto de estudio de la investigación especializada desde hace casi un siglo. Sin embargo, la localización exacta de los topónimos que en ellos figuran - fundamental para una plena comprensión de la estructura de las propiedades de Vicente -, era un aspecto pendiente de un análisis exhaustivo. El presente artículo aborda este problema,
combinando el trabajo de campo arqueológico con la crítica histórica de los aspectos internos del documento, incorporando además el estudio de la documentación medieval, con el fin de rastrear la pervivencia de los topónimos del siglo VI en el periodo posterior. El trabajo ha permitido identificar con seguridad sobre el terreno aproximadamente el cincuenta por ciento de la toponimia menor, lo que habilita un análisis histórico de la forma en que Vicente de Asán tenía organizado su patrimonio. Su centro de intereses está claramente localizado en la zona del Pirineo oscense, en los valles de La Fueva y Boltaña, las antiguas terrae terrantonense y boletana del documento. Pero además, la larga gestión de un patrimonio familiar, ha dado lugar a la posesión de tierras a lo largo de los valles del Ésera y Cinca, alcanzando incluso el valle del Ebro, con propiedades en los territorios de Barbotum, Labitolosa, Ilerda y Caesaraugusta. De esta organización de las tierras se deduce una economía complementaría entre las zonas bajas de los valles de los grandes ríos y las zonas de montaña, lo cual permite una diversificación de los
productos y un mejor aprovechamiento de los recursos. La ganadería se revela como un aspecto importante, pudiendo afirmarse que existe una trashumancia de corto recorrido para aprovechar la variación estacional. Además la restitución de la microtoponimia en el paisaje permite extraer otras conclusiones. Por un lado es posible definir con cierto detalle las fronteras entre los territorios urbanos que se mencionan en los textos. Por otro es posible detectar que las líneas de colonización interna de época medieval son continuadoras de las que tenemos documentadas en época visigoda. / ENGLISH: The donation and will of St. Vicente of Asán, dating from a. 551 and a. 576 respectively,
are two basic documents when getting to know the property structure in the Visigothic period.
These documents have been subjected to specialised research during nearly a century. However, the exact localization of the toponyms contained in them - a fundamental point for a full understanding of the structure of Vicente’s properties - was an unsolved question in their exhaustive analysis. This paper tackles on this problem, combining archaeological field work with the historical review of the inner aspects of the document, also including the study of the mediaeval documentation in order to trail the survival of VIth century toponyms in the subsequent period. This work has allowed us to identify with certainty and on the field approximately 50% of minor toponyms, which makes possible to carry out a historical analysis of the way in which Vicente of Asán had his patrimony organised. His centre of interest is clearly located in the Pyrenean area of Huesca, in La Fueva and Boltaña valleys (the ancient terrae terrantonensis and boletana of the document). But, in addition to this, the long lasting management of a family
patrimony gave rise to the possession of land along the rivers Esera and Cinca valleys, reaching even the Ebro valley, with properties in the territories of Barbotum, Labitolosa, Ilerda and Caesaraugusta. From this land organisation we can infer a complementary economy between the lands on the valleys of the main rivers and the mountain areas, which allowed produce diversification and a better exploitation of resources. Cattle raising appears as an important aspect, and it can even be stated that it existed a short-distance transhumance which took advantage of seasonal variations. Furthermore, the restitution of landscape microtoponymy allows to extract other conclusions. On the one hand, it is possible to define with some detail the borders of the urban territories mentioned by the texts; on the other, it is possible to detect that the lines of inner colonisation of mediaeval times continued those documented for the Visigothic period
Community structure in industrial SAT instances
Modern SAT solvers have experienced a remarkable progress on solving industrial instances. It is believed that most of these successful techniques exploit the underlying structure of industrial instances. Recently, there have been some attempts to analyze the structure of industrial SAT instances in terms of complex networks, with the aim of explaining the success of SAT solving techniques, and possibly improving them.
In this paper, we study the community structure, or modularity, of industrial SAT instances. In a graph with clear community structure, or high modularity, we can find a partition of its nodes into communities such that most edges connect variables of the same community. Representing SAT instances as graphs, we show that most application benchmarks are characterized by a high modularity. On the contrary, random SAT instances are closer to the classical Erdös-Rényi random graph model, where no structure can be observed. We also analyze how this structure evolves by the effects of the execution of a CDCL SAT solver, and observe that new clauses learned by the solver during the search contribute to destroy the original structure of the formula. Motivated by this observation, we finally present an application that exploits the community structure to detect relevant learned clauses, and we show that detecting these clauses results in an improvement on the performance of the SAT solver. Empirically, we observe that this improves the performance of several SAT solvers on industrial SAT formulas, especially on satisfiable instances.Peer ReviewedPostprint (published version
Drowsiness detection in drivers with a smartwatch
The main objective of this work is to detect early if a driver shows symptoms
of sleepiness that indicate that he/she is falling asleep and, in that case,
generate an alert to wake him/her up. To solve this problem, an application has
been designed that collects various parameters, through a smartwatch while
driving. First, the application detects the driving action. Then, it collects
information about the most significant physiological variables of a person
while driving. On the other hand, given the high level of sensitivity of the
data managed in the designed application, in this work special attention has
been paid to the security of the implementation. The proposed solution improves
road safety, reducing the number of accidents caused by drowsiness while
driving
Effects of Whole-Grain and Sugar Content in Infant Cereals on Gut Microbiota at Weaning: A Randomized Trial
The introduction of complementary foods during infancy marks an important step in the
development of the infant gut microbiome. Infant cereals are popular weaning foods but consistent
evidence on their effect on the intestinal microbiota, especially when differing in nutritional quality,
is lacking. Fecal samples from 4–7-month-old Spanish infants who consumed infant cereals differing
in whole grain and sugar content as first weaning foods were analyzed on changes in microbial
composition by massively parallel sequencing of the 16S ribosomal RNA gene at baseline and
after 7 weeks of intervention. Samples were obtained from a previous trial conducted in Spain
demonstrating whole-grain cereal acceptability. In total, samples of 18 infants consuming 0% whole
grain cereals with 24 g sugar (0-WG) and 25 infants consuming 50% whole grain cereals with 12 g
sugar (50-WG) were analyzed. Microbial composition changed significantly over time (p = 0.001), per
intervention group (p = 0.029) and per infant (p = 0.001). Abundance of genus Veillonella increased in
both groups while Enterococcus decreased. Within the 0-WG group, phylum Actinobacteria decreased
along with genus Bifidobacterium. In the 50-WG, we observed an increase in Lachnoclostridium and
Bacteroides. In addition, 50-WG decreased Proteobacteria and Escherichia to levels lower than 0-WG.
Although weaning itself appeared to be responsible for most changes, the increased presence of
anaerobic fermenters together with inhibition of pathogenic Escherichia may indicate a supporting
effect of infant cereals with 50% whole grains and a reduced sugar content over infant cereals
manufactured with refined hydrolyzed flours on the infant microbiota. In fact, using a novel
methodology for the identification of microbial signatures, we found two groups of microbial taxa
predictive of infants consuming enriched whole-grain infant cereals with a high predictive value of
about 93%.European funding from ICEX and FEDER—Program
R + D Invest 539 in Spain 2015European Regional Development Fund: 20150347
Magnetic field production during preheating at the electroweak scale
We study the generation of magnetic fields during preheating within an
scenario of hybrid inflation at the electroweak (EW) scale. We find that the
non-perturbative and strongly out-of-equilibrium process of magnetic field
production occurs along the lines predicted by Vachaspati many years ago. The
system starts in the false vacuum at the end of inflation, and very quickly the
initial quantum fluctuations of the Higgs field get amplified via long
wavelength spinodal instabilities. The subsequent nucleation of the random
Gaussian Higgs field bubbles (lumps) leads to EW symmetry breaking, and to the
creation of -strings, which soon decay, along with longwave magnetic flux
tubes with nontrivial helicity. The intensity and scales in these helical
magnetic fields are consistent with their later development into the microgauss
fields observed in galaxies and clusters of galaxies.Comment: 4 pages, 6 figures, uses revtex
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