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271.
Eduardo Krüger Patricia Drach Rohinton Emmanuel Oscar Corbella 《Theoretical and Applied Climatology》2013,112(1-2):127-141
From extensive outdoor comfort campaigns, preliminary outdoor comfort ranges have been defined for the local population of Glasgow, UK, in terms of two thermal indices: ‘Temperature Humidity Sun Wind’ (THSW) and ‘Physiological Equivalent Temperature’ (PET). A series of measurements and surveys was carried out from winter through summer 2011 during 19 monitoring campaigns. For data collection, a Davis Vantage Pro2 weather station was used, which was equipped with temperature and humidity sensors, cup anemometer with wind vane, silicon pyranometer and globe thermometer. From concurrent measurements using two weather stations, one located close to the city core and another located at a rural setting, approximately at a 15-km distance from the urban area of Glasgow, comparisons were made with regard to thermal comfort levels and to urban–rural temperature differences for different periods of the year. It was found that the two selected thermal indices (THSW and PET) closely correlate to the actual thermal sensation of respondents. Moreover, results show that the urban site will have fewer days of cold discomfort, more days of ‘neutral’ thermal sensation and slightly higher warm discomfort. The most frequent urban heat island intensity was found to be around 3° C, whereas the fraction of cooling to heating degree-hours for a T base of 65 °F was approximately 1/12th. 相似文献
272.
Shannon E. Brown Jon S. Warland Eduardo A. Santos Claudia Wagner-Riddle Ralf Staebler Meaghan Wilton 《Boundary-Layer Meteorology》2013,147(1):83-102
Analytical Lagrangian equations capable of predicting concentration profiles from known source distributions offer the opportunity to calculate source/sink distributions through inverted forms of these equations. Inverse analytical Lagrangian equations provide a practical means of estimating source profiles using concentration and turbulence measurements. Uncertainty concerning estimates of the essentially immeasurable Lagrangian length scale ( ${\mathcal{L}}$ ), a key input, impedes the operational practicality of this method. The present study evaluates ${\mathcal{L}}$ within a corn canopy by using field measurements to constrain an analytical Lagrangian equation. Measurements of net CO2 flux, soil-to-atmosphere CO2 flux, and in-canopy profiles of CO2 concentration provided the information required to solve for ${\mathcal{L}}$ in a global optimization algorithm for 30-min time intervals. For days when the canopy was a strong CO2 sink, the optimization frequently located ${\mathcal{L}}$ profiles that follow a convex shape. A constrained optimization then fit the profile shape to a smooth sigmoidal equation. Inputting the optimized ${\mathcal{L}}$ profiles in the forward and inverse Lagrangian equations leads to strong correlations between measured and calculated concentrations and fluxes. Coefficients of the sigmoidal equation were specific to each 30-min period and did not scale with any measured variable. Plausible looking ${\mathcal{L}}$ profiles were associated with negative bulk Richardson number values. Once the canopy senesced, a simple eddy diffusivity profile sufficed to relate concentrations and sources in the analytical Lagrangian equations. 相似文献
273.
274.
Julio Iglesias de Ussel Antonio Trinidad Diego RuIz Eduardo Battaner Antonio J. Delgado José M. Rodriguez-Espinosa Eduard Salvador-Solé José M. Torrelles 《Astrophysics and Space Science》1997,257(2):237-248
In this paper the main findings are presented of a recent study made by a team of sociologists from the University of Granada
on the professional astronomers currently working in Spain. Despite the peculiarities of this group – its youth, twentyfold
increase in size over the last 20 years, and extremely high rate of specialization abroad – in comparison with other Spanish
professionals, this is the first time that the sociological characteristics of the group have been studied discretely. The
most significant results of the study are presented in the following sections. Section 1 gives a brief historical background
of the development of Astronomy in Spain. Section 2 analyzes the socio-demographic profile of Spanish Astronomy professionals
(sex, age, marital status, etc.). Sections 3–5 are devoted to the college education and study programs followed by Spanish
astronomers, focusing on the features and evaluations of the training received, and pre- and postdoctoral study trips made
to research centers abroad. The results for the latter clearly show the importance that Spanish astronomers place on having
experience abroad. Special attention is paid to scientific papers published as a result of joint research projects carried
out with colleagues from centers abroad as a result of these study trips. Section 6 describes the situation of Astronomy professionals
within the Spanish job market, the different positions available and the time taken to find a job after graduation. Section
7 examines Astronomy as a discipline in Spain, including the astronomers' own opinions of the social status of the discipline
within Spanish society. Particular attention is paid to how Spanish astronomers view the status of Astronomy in Spain in comparison
with that of other European countries.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
275.
276.
Eduardo M. García-Roger M. del Mar Sánchez-Montoya Rosa Gómez M. Luisa Suárez M. Rosario Vidal-Abarca Jérôme Latron Maria Rieradevall Narcís Prat 《Aquatic Sciences - Research Across Boundaries》2011,73(4):567-579
In this study we examined the importance of seasonal changes in habitat features and aquatic macroinvertebrate responses in
temporary and perennial streams from two different catchments in the Western Mediterranean region in Spain. Macroinvertebrate
sampling was spatially intensive to account for the relative frequency of meso- (i.e., riffles and pools) and micro-habitats
(i.e., different mineral and organic-based substrata) at each site. Samples were collected at two distinctly different phases
of the hydrograph: (1) during the flowing period, when pool-riffle sequences were well-established, and (2) during the dry
phase, when only isolated pools were expected to occur in the temporary streams. During the dry season, both a reduction in
the available total habitat and in microhabitat diversity in all sites studied was observed. As a result, taxon richness decreased
in all streams, but more dramatically at temporary stream sites and particularly so in the infrequently remaining discontinuous
riffles. Macroinvertebrate assemblages differed among catchments (i.e., geographical identity) and sites (perennial vs. temporary).
Invertebrate differences were also strong within and among meso- and micro-habitats, particularly mineral and organic microhabitat
patches, and differences were due to both loss of taxa from some habitats and some taxa exhibiting certain habitat affinities. 相似文献
277.
Carles Canet Sara I. Franco Rosa María Prol-Ledesma Eduardo González-Partida Ruth Esther Villanueva-Estrada 《Journal of Geochemical Exploration》2011
Boiling can be inferred from fluid inclusion microthermometry studies when a progressive increase in apparent salinity is observed along with a decrease of homogenization temperature (TH) and depth, thus reflecting the partitioning of non-volatile solutes into the liquid phase during steam loss. We propose a model for fluid evolution during boiling based on mass and heat balance equations, which establishes paths in the TH-salinity space that can be compared with fluid inclusion data to confirm or discard boiling. Additionally, the model allows calculating paleo-depths, for which the effect of steam bubbles lowering the hydrostatic pressure is taken into account. 相似文献
278.
Eduardo M. Bretas José V. Lemos Paulo B. Lourenço 《Rock Mechanics and Rock Engineering》2013,46(2):327-339
A numerical model for the hydromechanical analysis of masonry dams based on the discrete element method is presented. The dam and the rock foundation are represented as block assemblies, and a coupled flow-stress analysis is performed in an integrated manner for the entire system. Complex block shapes may be obtained by assembling elementary blocks into macroblocks, allowing the application of the model to situations ranging from equivalent continuum to fully discontinuum analysis. A contact formulation was developed based on an accurate edge–edge approach, incorporating mechanical and hydraulic behavior. The main numerical aspects are described, with an emphasis in the flow analysis explicit algorithm. An application to an existing masonry dam is presented, analyzing its present condition, with excessive seepage, and the proposed rehabilitation intervention. An evaluation of sliding failure mechanisms was also performed, showing the expected improvement in the safety of the structure. 相似文献
279.
AbstractDetrital zircon populations from Carboniferous to Permian sandstones from the Lozar Section of Spiti, northern India, were analyzed with the typology method in order to obtain complementary information on the source areas of the sediments. Zircon grains were subdivided into several groups and subgroups, according to degree of abrasion and morphological features.First appearance of detrital zircons with distinct typologic signature within successive stratigraphic intervals provided useful data about the tectono-magmatic evolution of the northern Indian margin during Late Paleozoic rifting of Gondwana and initial opening of Neotethys. The base of the studied sequence (Lower Carboniferous Thabo Fm.) is characterized by a largely cratonic provenance, seemingly from the Indian Shield to the South. In the Upper Carboniferous Chichong Fm., first occurrence of typical zircons from anatectic granites and increasing abundance of granitoid detritus suggest rapid uplift and unroofing of anatectic rocks of probable Cambro-Ordovician age. In the lowermost Permian (Asselian) glaciomarine Ganmachidam Diamictite, euhedral detrital zircons with peculiar features, associated with Cr-rich chromian spinels and mafic to felsic volcanic rock fragments, hint at emplacement of bimodal alkaline magmatic suites. The same sources, possibly including subvolcanic bodies, continued to be eroded until final break-up, documented by the Permian Kuling Group. 相似文献
280.
Numerical study on the effect of submerged depth on the horizontal plate wave energy converter 总被引:2,自引:0,他引:2
Flávio Medeiros SEIBT ;Eduardo Costa COUTO ;Elizaldo Domingues dos SANTOS ;Liércio André ISOLDI ;Luiz Alberto Oliveira ROCHA 《中国海洋工程》2014,28(5):687-700
The growing search for clean and renewable energy sources has given rise to the studies of exploring sea wave energy. This paper is concerned with the numerical evaluation of the main operational principle of a submerged plate employed for the conversion of wave energy into electrical one. The numerical model used to solve the conservation equations of mass, momentum and transport of volume fraction is based on the finite volume method (FVM). In order to tackle with the flow of mixture of air-water and its interaction with the device, the multiphase model volume of fluid (VOF) is employed. The purpose of this study is the evaluation of a numerical model for improvement of the knowledge about the submerged plate wave energy converter, as well as the investigation of the effect of the distance from the plate to the bottom of the sea (HP) on the performance of the converter. The simulations for several distances of the plate from the seabed show that the optimal efficiency is 64%, which is obtained for HP=0.53 m (88% of the depth). This efficiency is 17% larger than that found in the worst case (HP=0.46 m, 77% of the depth). 相似文献