3,396 research outputs found
Forecasting accuracy of behavioural models for participation in the arts
A first version of this paper was presented at the University of Catania, 2011 and at the fifth European Workshop on Applied Cultural Economics in Dublin, 2011.forecasting, count data, prediction intervals, Brier scores, bootstrapping, arts
RODRÍGUEZ ESTEBAN, María Ascensión. "La arquitectura de ladrillo y su construcción en la ciudad de Zamora (1888-1931)"
López Eire, Antonio y Velasco López, María del Henar, "La mitología griega: lenguaje de dioses y hombres."
Routing design for less-than-truckload motor carriers using ant colony techniques
One of the most important challenges for Less-Than-Truck-Load carriers consists of determining how to consolidate flows of small shipments to minimize costs while maintaining a certain level of service. For any origin-destination pair, there are several strategies to consolidate flows, but the most usual ones are: peddling/collecting routes and shipping through one or more break-bulk terminals. Therefore, the target is determining a route for each origin-destination pair that minimizes the total transportation and handling cost guaranteeing a certain level of service. Exact resolution is not viable for real size problems due to the excessive computational time required. This research studies different aspects of the problem and provides a metaheuristic algorithm (based on Ant Colonies Optimization techniques) capable of solving real problems in a reasonable computational time. The viability of the approach has been proved by means of the application of the algorithm to a real Spanish case, obtaining encouraging results
El polen de Poaceae en la atmósfera de Lugo y su relación con los parámetros meteorológicos (1999-2001)
. El polen de Poaceae en la atmósfera de Lugo y su relación con los parámetros meteorológicos (1999-2001). Se han estudiado las concentraciones de polen de Poaceae presente en la atmósfera de la ciudad de Lugo durante 3 años (1999-2001). Para ello se ha utilizado un captador volumétrico tipo Hirst, modelo Lanzoni VPPS-2000. El polen de Poaceae es el más abundante y su porcentaje frente al total de polen anual es de un 38-40%. La cantidad total de polen anual es de 8.400 granos como resultado de la media de los tres años de estudio, con un período de polinización durante los meses de Junio y Julio. A lo largo del día los máximos de concentración tienen lugar durante la tarde. Se ha realizado un análisis de correlación con los principales parámetros meteorológicos, siendo la temperatura máxima la variable que presentó el coeficiente más elevado. La suma acumulada de la temperatura máxima y la regresión múltiple integrando la temperatura máxima y las concentraciones de polen del día anterior como estimadores, resultaron métodos válidos y complementarios para realizar la predicción del inicio del periodo de polinización y de las concentraciones medias diarias que se alcanzan durante el periodo de polinización principal respectivament
Estudio palinológico de mieles de montaña de la provincia de Orense (NW-España)
In the following study a quantitative and qualitative analysis of thirteen samples of honey is realised. The honey is extracted from beehives all of which are located at an altitude between 600 m to 1000 m in the province of Orense (NW Spain). In eleven of the samples the dominant pollen is Castanea sativa, reaching in three of them a percentage between 80-84%. The pollen of Rubus sp. is also dominant in one of honeys studied, wich a percentage of 67%. The nine remaining honeys are polyfloral and as well as Castanea sativa and Rubus sp. other pollens are commonly present, these being: Adenocarpus complicatus, Campanula sp., Hypericum perforatum, Lotus corniculatus , Prunus sp., Crataegus mono gina and Ericaceae.Se analizan cualitativa y cuantitativamente trece muestras de miel procedentes de colmenares ubicados en la zona montañosa oriental de Galicia, entre los 600 y 1000 m de altitud. En once de las muestras, aparece como polen dominante Castanea sativa Miller, alcanzando valores en tres de ellas entre el 80-84%. Rubus sp. es dominante en una de las mieles estudiadas, en la que alcanza un 67%, mientras que las restantes muestras se consideran multiflorales, con abundancia, además de los táxones citados, de otros tipos polánicos como: Adenocarpus complicatus DC., Campanula sp., Hypericum perforatum L., Lotus corniculatus L., Prunus sp., Crataegus mono gina Jacq. y Ericaceae
Do close range measurements affect the target strength (TS) of fish in horizontal beaming hydroacoustics?
Detailed fish target strength (TS) studies allow us to relate their physical and biological variables to their sound behaviour and they potentially improve the accuracy of acoustic assessments. One of the limitations of the transducers that are currently used is their difficulty to precisely estimate TS at close range, either because the acoustic beam may not include the whole fish or because of the near-field effect. When measuring the sound produced by a target (fish), it is recommended that the so-called near-field area, which is generated immediately in front of the target, should be avoided. In horizontal hydroacoustics, where information is obtained within the first 15–20 m from the transducer, avoiding this near-field area may render the majority of the sampled volume useless. This experiment was developed in order to study the horizontal behaviour of the TS with regard to distance. We have studied three different sizes of free-swimming large carps and barbels (≈300, 400 and 500 mm) and we have recorded fish traces at three distances from the transducer, both fulfilling and not fulfilling the requirements of the near-field (6, 9 and 12 m). The results showed no differences in the mean TS obtained for fish at different distances. Factors such as orientation or size showed a greater influence on TS changes. These results are very encouraging and they support the use of hydroacoustics in studies performed at close range, such as studies of fish migration in rivers or biomass estimations in aquaculture
Largemouth bass, Micropterus salmoides, growth and reproduction in Primera de Palos’ lake (Huelva, Spain)
Some aspects of the biology of Micropterus salmoides such as growth, population
structure and reproduction, were studied in the Primera de Palos’ lake. A total of 200 specimens were
captured (98 females, 86 males and 16 juveniles) and distributed into seven different age-classes
(from 0+ to 6+). Specimens 6+ were exclusively females. The mean values of male length and
weight were slightly higher than females ones but the differences were not significant between sexes.
The parameters of the von Bertalanffy growth’s curve were L∞=503.6 mm, k=0.19, t0=-1.04 for
males and L∞=512.6, k=0.18, t0=-1.05 for females. The final values of the Gompertz growth’s curve
for weight were: W0=36.35, G=10.61, g=0.06 for males and W0=31.81, G=6.93, g=0.11 for females.
Reproduction took place in spring. Females mature older than males, in age-class 2+. The results
clearly indicate that the largemouth bass population has acclimatised well to the Primera de Palos’
lake, having found environmental and trophic conditions that are favourable to its development
Variaciones intranuales del espectro polínico de miel de Nogueira de Ramuín, Orense
Se ha realizado el análisis polínico de 12 muestras recogidas de forma secuencial durante el periodo de producción de miel en tres colmenas, ubicadas en Nogueira de Ramuin (Orense), comparando los resultados obtenidos con el espectro polínico de la mezcla final. Se observan diferencias importantes entre las muestras parciales, que ponen de manifiesto el pecoreo selectivo de las distintas colonias
Mazzia, Maria Maddalena, Gli atti amministrativi generali, Università Pontificia Salesiana, Roma 2000, 181 pp. [RECENSIÓN]
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