A statistical investigation of the behavioural responses of a deep diving predator to mesoscale oceanographic features

Includes bibliographical references.Marion Island lies directly in the path of the ACC and to the south-west of the island is an extensive region of high sea level anomaly variability (eddy field). Previous research has shown how southern elephant seals from Kerguelen Island and Peninsula Valdés have targeted eddies for foraging. These findings combined with the observed post-moult migrations of tagged female southern elephant seals from Marion Island which traverse the nearby eddy field suggest that they may exploit the eddy field for foraging. Overall the seals undertook significantly more of their dives (18.5) within the eddy field than predicted (p < 0.01). Eleven of the 16 seals dived within the eddy field region significantly more often than predicted. Dives were generally shallower and shorter within the eddy field. Mixed models estimated that a maximum depth reduction of 53.03 ± 5.30 m (LME: t=10.00, DF=24986, p < 0.01) and a dive duration reduction of 6.17 ± 0.58 min (LME: t=10.70, DF=24986, p < 0.01) could be attributed to diving within the eddy field. Within the eddy field U-dives increased by 6.97, W dives decreased by 7.18 and O-dives increased by 0.21. Seven individuals’ maximum dive depths were shallower and nine individuals dive durations were shorter as a result of diving within the eddy field. Ten individuals showed significant changes in the types of dives which they undertook inside of the eddy field with eight seals undertaking more Uand fewer W-dives and two seals undertaking more W- and fewer U-dives. Overall the effect of diving within the eddy field appeared to be biologically important to ten seals. While dive durations were significantly affected by changing sea level anomaly (SLA) (LME: 0.15 ± 0.01 min, t=11.72, DF=12372, p < 0.01), maximum depths were not. The log-odds of switching from U- to W-dives within the eddy field were significantly affected by changing SLA (Multinomial: 0.00 ± 0.00, z=2.97, p < 0.01). However all significant effects of SLA on dive parameters within the eddy field were very small in comparison to those of day-stage. The low magnitudes of the effects of SLA were similar for all individuals

Steklov Spectral Geometry for Extrinsic Shape Analysis

We propose using the Dirichlet-to-Neumann operator as an extrinsic alternative to the Laplacian for spectral geometry processing and shape analysis. Intrinsic approaches, usually based on the Laplace-Beltrami operator, cannot capture the spatial embedding of a shape up to rigid motion, and many previous extrinsic methods lack theoretical justification. Instead, we consider the Steklov eigenvalue problem, computing the spectrum of the Dirichlet-to-Neumann operator of a surface bounding a volume. A remarkable property of this operator is that it completely encodes volumetric geometry. We use the boundary element method (BEM) to discretize the operator, accelerated by hierarchical numerical schemes and preconditioning; this pipeline allows us to solve eigenvalue and linear problems on large-scale meshes despite the density of the Dirichlet-to-Neumann discretization. We further demonstrate that our operators naturally fit into existing frameworks for geometry processing, making a shift from intrinsic to extrinsic geometry as simple as substituting the Laplace-Beltrami operator with the Dirichlet-to-Neumann operator.Comment: Additional experiments adde

Geometry Textures and Applications

International audienceGeometry textures are a novel geometric representation for surfaces based on height maps. The visualization is done through a GPU ray casting algorithm applied to the whole object. At rendering time, the fine-scale details (mesostructures) are reconstructed preserving original quality. Visualizing surfaces with geometry textures allows a natural LOD behavior. There are numerous applications that can benefit from the use of geometry textures. In this paper, besides a mesostructure visualization survey, we present geometry textures with three possible applications: rendering of solid models, geological surfaces visualization and surface smoothing

Implicit Decals: Interactive Editing of Repetitive Patterns on Surfaces

11 pagesInternational audienceTexture mapping is an essential component for creating 3D models and is widely used in both the game and the movie industries. Creating texture maps has always been a complex task and existing methods carefully balance flexibility with ease of use. One difficulty in using texturing is the repeated placement of individual textures over larger areas. In this paper we propose a method which uses decals to place images onto a model. Our method allows the decals to compete for space and to deform as they are being pushed by other decals. A spherical field function is used to determine the position and the size of each decal and the deformation applied to fit the decals. The decals may span multiple objects with heterogeneous representations. Our method does not require an explicit parameterization of the model. As such, varieties of patterns including repeated patterns like rocks, tiles, and scales can be mapped. We have implemented the method using the GPU where placement, size, and orientation of thousands of decals are manipulated in real time

Updating the wave-particle duality

Updating the wave-particle duality María C. Boscá e-mail: [email protected] Departamento de Física Atómica, Molecular y Nuclear Universidad de Granada E-18071. Granada Spain The wave-particle-duality, the fundamental component of the new quantum formalism in Bohr’s opinion, must be reformulated by incorporating the results of some experiments accomplished in the last decades of twentieth century. The Bohr´s complementarity principle stated the mutual exclusiveness and joint full completeness of the two (classical) descriptions of quantum systems; after Einstein-Podolsky-Rosen’paper, the wave-particle duality, or wave-particle complementarity, could be expressed by stating that it is impossible to build up an experimental arrangement in which we observe at the same time both corpuscular and wave aspects. In a two-slit experiment, they would correspond, respectively, to the which-way knowledge and the observation of interference pattern. Bohr showed this mutual exclusivity in numerous examples , and linked it to the unavoidable disturbance inherent in any measurement event. In quantum mechanical formalism, the complementarity principle has a clear mathematical expression: two observables are complementary if precise knowledge of one of them implies that all possible outcomes of the other are equally probable; their extension to classical concepts (as wave and particle) is not concerned. In 1991 Scully et al published a variant of the two-slit experiment that incorporates two micromasers cavities and a laser beam to provide which-path information without net momentum transferred during the interaction ; the impossibility of know which slit an atom went through and still observe the interference fringes is preserved by the establishing of quantum correlations between the measuring apparatus and the system being observed. They claimed that complementarity, of which wave-particle duality would be to them a manifestation, is more fundamental than the uncertainty principle . In 1996 B-G. Englert, following an approach originally due to Wooters and Zurek , derived , without making use of Heisenberg’s uncertainty relation, an inequality that quantifies the mutual compatibility relation between fringe visibility and which-way information. The inequality, that they denominated as “interferometric duality”, has the expression D^2 + V^2 ≤ 1, where D stands for the distinguishability of the ways and V for the fringe visibility; both of them are mathematical expressions that can be measured to check experimentally the inequality . Today, it is clear that intermediate particle-wave behaviours exist and, in addition to that, there are single experiments in which both classical wave-like and particle-like behaviours are showed total and simultaneously on an individual system. For instance, in the Bose’s double-prism experiment , tunnelling and perfect anticoincidence were observed in single photon states. Consequently, the meaning of the wave-particle duality must incorporate the simultaneous use of the two classical descriptions in the interpretation of experiments, loosing their original mutual exclusivity , which is incorporated as an extreme case in the new interferometric duality, a continuous quantum concept . The wave-particle duality, therefore, must be formulated as an interpretative addition to quantum mechanics, to which is possible to renounce if any pretension of visualize quantum phenomena in terms of classical concepts and intuitions is abandoned

Chinese Stardom in Participatory Cyberculture

As Chinese performers have become more visible on global screens, their professional images - once the preserve of studios and agents - have been increasingly relayed and reworked by film fans. Web technology has made searching, poaching, editing, posting and sharing texts significantly easier, and by using a variety of seamless and innovative methods a new mode of personality construction has been developed. With case studies of high-profile stars like Jet Li, Jackie Chan and Donnie Yen, this ground-breaking book examines transnational Chinese stardom as a Web-based phenomenon, and as an outcome of the participatory practices of cyber fans

Nakhi tiger myth in its context

Tiger belief is popular in the Tibeto-Burmese language family. In recent years, academic circles at home and abroad discovered it among the Yi, Hani, and Lisu. However, tiger belief among the Nakhi,1 one of the most important Tibeto-Burmese language families, is still largely unknown, a fact that impedes our general understanding when we consider the language family as a whole. To make up for this deficiency, the author will try to sort out the background of Nakhi tiger myth and provide a general perspective for the Tibeto-Burmese, or even China's, tiger cultures.Issue title: Chinese Oral Traditions

Geometry Textures

International audienceIn highly tessellated models, triangles are very small compared to the entire object, representing at the same time its macro- and mesostructures. The main idea in this work is to use a visualization algorithm that is adequate to mesostructure but applied to the whole object. Tessellated models are converted into geometry textures, a geometric representation for surfaces based on height maps. In rendering time, the fine-scale details are reconstructed with LOD speed-up while preserving original quality