The temporal evolution of the energy flux across scales in homogeneous turbulence

A temporal study of energy transfer across length scales is performed in 3D numerical simulations of homogeneous shear flow and isotropic turbulence. The average time taken by perturbations in the energy flux to travel between scales is measured and shown to be additive. Our data suggests that the propagation of disturbances in the energy flux is independent of the forcing and that it defines a `velocity' that determines the energy flux itself. These results support that the cascade is, on average, a scale-local process where energy is continuously transmitted from one scale to the next in order of decreasing size.Comment: Accepted for publication as a Letter in Physics of Fluid

Ovoposició en poblacions de "Physa acuta" "(Gastropoda: Pulmonata)" mantingudes al laboratori

The ovipositional parameter, number of egg masses/snailxday, has been recorded in laboratory-kept populations of Physa acuta in the period 1973-1975. The results show a clear non circadian rhythm with a period slightly over 3 days long, and whose extent depends on the provenance of the populations being not related to the seasonal period. Further, the rhythm found is significatively correlated to the atmospheric ressure change. So, the suggestion is made that some geophysical actor correlated to the atmospheric pressure affects the ovipositional activity in Physa acuta. Moreover, it is shown too that the change of water stimulates it

Notes sobre el desenvolupament embrionari dels cargols d'aigua dolça "Physa acuta" i "P. fontinalis" (Gasteròpodes, Pulmonats)

The development of two species of Physids (Physa acuta and P. Fontinalis) is studied. On the whole they agree with the early description given by Wierzejski, though our study adds two points worth considering. Firstly, there is a clear asymmetry in the dorsal half of the trochophore as shown by the shell gland displacement to the right and further by the fact that cell Id22 is placed higher than lc22 in the dorsal region of the head vesicle. The possible mechanisms leading to both asymetries are discussed. Secondly, the invaginating shell gland and radular sac are the RNA richest tissues in the trochophore. The possible relationships between cell differentiation pathway and this RNA endowment are discussed for both tissues. Finally, in the species studied, there is a clear relationship between the enteroblasts and the gut wall during the development of the hindgut. This result is clearly at variance with Wierzejski's description

Detection of Walls, Floors, and Ceilings in Point Cloud Data

This is the author accepted manuscript. The final version is available from the American Society of Civil Engineers via http://dx.doi.org/10.1061/9780784479827.229The successful implementation of Building Information Models (BIMs) for facility management, maintenance and operation is highly dependent on the ability to generate such models for existing assets. Generating such BIMs typically requires laser scanning to acquire point clouds and significant post-processing to register the clouds, replace the points with BIM objects, assign semantic relationships and add any additional properties, such as materials. Several research efforts have attempted to reduce the post-processing manual effort by classifying the structural elements and clutter in isolated rooms. They have not however examined the complexity of a whole building. In this paper, we propose a robust framework that can automatically process the point cloud of an entire building, possibly with multiple floors, and classify the points belonging to floors, walls and ceilings.. We first extract the planar surfaces by segmenting the point cloud, and then we use contextual reasoning, such as height, orientation, relation to other objects, and local statistics like point density in order to classify them into objects. Experiments were conducted on a registered point cloud of an office building. The results indicated that almost all of the walls and floors/ceilings were correctly clustered in the point cloud.The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreements n° 247586 ("BIMAutoGen") and n° 334241 ("INFRASTRUCTUREMODELS")

El turismo rural-cultural : un modelo de gestión del marketing turístico a nivel local basado en la medida de la imagen del destino

El excursionismo y turismo a núcleos de pequeño tamaño con riqueza histórico-patrimonial y ubicados en el entorno rural es evidente en nuestro país. En este trabajo se propone una conceptualización y definición de lo que se entiende por excursionismo y/o turismo en destinos rurales-culturales, una propuesta del conjunto de variables conformadores de la imagen de este tipo de destinos y las características y perfil de este tipo de excursionismo y del excursionista o turista rural-cultural. La investigación empírica realizada, de naturaleza cualitativa y cuantitativa, presenta como principales resultados la identificación del conjunto de componentes cognitivo-afectivos conformadores de la imagen, una alta consistencia interna y correlación de los mismos con la imagen del destino y una descripción de las principales características de este tipo de excursionismo y motivos del excursionista ruralcultural. Sobre esta base se propone un modelo de gestión del marketing turístico a nivel local basado en la imagen del destino y su medida.Day trips and tourism in, rural villages with a rich historical heritage are to be found in this country as in others of similar characteristics. This work presents a conceptualisation and definition of what is understood as day trips or tourism in rural/cultural destinations and it proposes a combination of variables which conform to the image of the destination and characteristics of these types of trips and of the day tripper or rural/cultural tourist. The principal results of the empirical investigation, which by its very nature is a qualitative and quantitative one, are the identification of a combination of cognitive/affective components which conform to the image; a high internal consistence and correlation of the same with the image of the destination; a description of the main characteristics of this kind of day trip; the main sources of information and motives for rural/cultural tourism. On this basis is point out a local tourism marketing management model based on image destination and its measure

Narcissus dubius, Narcisse Douteux

This species is endemic to southern France and eastern Spain. It is assessed as Least Concern because it has a widespread distribution, occurs in several protected areas throughout its range and its population is not expected to significantly decline in the near future. Further studies on the genetic structure of its population and trends in population size at global level are needed

Reactions with 1-Benzotriazolecarboxylic Acid Chloride. I. Synthesis of the 2,6-Bis(hydroxymethyl)pyridinedicarbamates

Some 2,6-bis(hydroxymethyl)pyridinedicarbamates VII were synthesized by reaction of pyridinedimethanole (I) with carbamoylazoles II-VI (azole=imidazole, benzimidazole, pyrazole, 1,2,4-triazole, benzotriazole). It is confirmed that this reaction proceed via an intermolecular elimination-addition acyl transfer mechanism including in the first step the formation of an isocyanate. Carbamoylbenzotriazoles Vla-i were prepared by aminolysis of 1-benzot,riazole-\u27 carboxylic acid chloride (VIII) obtained from benzotriazole and phosgene

A DEA-inspired approach to selecting parking areas for dangerous-goods trucks

The transport of dangerous goods by trucks requires special conditions for rest areas. By considering the set of existing service areas, the present work develops a procedure for selecting the subgroup of the most suitable service areas for modification in order to provide a service to dangerous-goods transporters. Under multiple criteria, a new DEA-inspired model is developed that uses the main characteristics of the problem under study with the goal of selecting the best locations. Through the application of this model to Spanish territory with the help of Geographical Information Systems, various solutions are suggested. The final decision on the number of areas to be located depends on corresponding authorities, whose main priority is to satisfy economic criteria