Search results for "immersio"
showing 10 items of 111 documents
Strongly invertible links and divides
2008
Abstract To a proper generic immersion of a finite number of copies of the unit interval in a 2-disc, called a divide, A’Campo associates a link in S 3 . From the more general notion of ordered Morse signed divides, one obtains a braid presentation of links of divides. In this paper, we prove that every strongly invertible link is isotopic to the link of an ordered Morse signed divide. We give fundamental moves for ordered Morse signed divides and show that strongly invertible links are equivalent if and only if we can pass from one ordered Morse signed divide to the other by a sequence of such moves. Then we associate a polynomial to an ordered Morse signed divide, invariant for these move…
REPRESENTATIVE BRAIDS FOR LINKS ASSOCIATED TO PLANE IMMERSED CURVES
2000
In [ AC 2], A'Campo associates a link in S3 to any proper generic immersion of a disjoint union of arcs into a 2-disc. We give a sample algorithmic way to produce, from the immersion, a representative braid for such links. As a by-product we get a minimal representative braid for any algebraic link, from a divide associated to a real deformation of the polynomial defining the link.
Solving underwater crimes: development of latent prints made on submerged objects.
2013
Underwater crime scenes always present a challenge for forensic researchers, as the destructive effect of water considerably complicates the chances of recovering material of evidential value. The aim of this study is to tackle the problem of developing marks that have been left on submerged objects. Fingermark deposition was randomly made on two surfaces - glass and plastic whilst the material was submerged under tap water and then left for one to fifteen days before drying and development. For their later development, various reagents - Black Powder, Silver Metallic Powder, Fluorescent Powder, Sudan Black (powder and solution) and Small Particle Reagent - were used and the effectiveness o…
Validation of the Virtual Reality Neuroscience Questionnaire: Maximum Duration of Immersive Virtual Reality Sessions Without the Presence of Pertinen…
2019
Research suggests that the duration of a VR session modulates the presence and intensity of VRISE, but there are no suggestions regarding the appropriate maximum duration of VR sessions. The implementation of high-end VR HMDs in conjunction with ergonomic VR software seems to mitigate the presence of VRISE substantially. However, a brief tool does not currently exist to appraise and report both the quality of software features and VRISE intensity quantitatively. The VRNQ was developed to assess the quality of VR software in terms of user experience, game mechanics, in-game assistance, and VRISE. Forty participants aged between 28 and 43 years were recruited (18 gamers and 22 non-gamers) for…
Máster de formación inicial del profesorado de enseñanza secundaria, algunos análisis y propuestas
2010
Se presentan algunos análisis y propuestas en torno al nuevo máster de formación inicial de profesorado de secundaria, para contribuir al necesario y urgente debate acerca de su desarrollo futuro.
Harmonicity and minimality of oriented distributions
2004
We consider an oriented distribution as a section of the corresponding Grassmann bundle and, by computing the tension of this map for conveniently chosen metrics, we obtain the conditions which the distribution must satisfy in order to be critical for the functionals related to the volume or the energy of the map. We show that the three-dimensional distribution ofS4m+3 tangent to the quaternionic Hopf fibration defines a harmonic map and a minimal immersion and we extend these results to more general situations coming from 3-Sasakian and quaternionic geometry.
Effect of Pseudomonas sp. MT5 baths on Flavobacterium columnare infection of rainbow trout and on microbial diversity on fish skin and gills
2005
Use of Pseudomonas sp. strain MT5 to prevent and treat Flavobacterium columnare infection was studied in 2 experiments with fingerling rainbow trout Oncorhynchus mykiss. In the first experiment, length heterogeneity analysis of PCR-amplified DNA fragments (LH-PCR) was used to assess the effect of antagonistic baths on the microbial diversity of healthy and experimentally infected fish. In the 148 samples studied, no difference was found between bathed and unbathed fish, and 3 fragment lengths were detected most frequently: 500 (in 75.7% of the samples), 523 (62.2%) and 517 bp (40.5%). The species contributing to these fragment sizes were Pseudomonas sp., Rhodococcus sp. and F. columnare, re…
A note on Sobolev isometric immersions below W2,2 regularity
2017
Abstract This paper aims to investigate the Hessian of second order Sobolev isometric immersions below the natural W 2 , 2 setting. We show that the Hessian of each coordinate function of a W 2 , p , p 2 , isometric immersion satisfies a low rank property in the almost everywhere sense, in particular, its Gaussian curvature vanishes almost everywhere. Meanwhile, we provide an example of a W 2 , p , p 2 , isometric immersion from a bounded domain of R 2 into R 3 that has multiple singularities.
Psychological Variables and Reality Judgment in Virtual Environments: The Roles of Absorption and Dissociation
2009
Literature on virtual reality (VR) and psychology has focused on the influence that some basic psychological processes have on VR. Although psychological processes may be defined as common to all humans, there are individual differences that might make it difficult to provide the same VR experience for everyone. Of the several personality and psychological variables that might be relevant to the VR field, this study focuses on two: absorption and dissociation. Both psychological dimensions are deeply interrelated and might play an important role in the immersion of subjects in virtual environments and in the reality attributions they make. Thus, the purpose of this study was to ascertain pe…
Pseudo-haptic Controls for Mid-air Finger-based Menu Interaction
2019
Virtual Reality (VR) is more accessible than ever these days. While topics like performance, motion sickness and presence are well investigated, basic topics as VR User Interfaces (UIs) for menu control are lagging far behind. A major issue is the absence of haptic feedback and naturalness, especially when considering mid-air finger-based interaction in VR, when "grabbable" controllers are not available. In this work, we present and compare the following two visual approaches to mid-air finger-based menu control in VR environments: a planar UI similar to common 2D desktop UIs, and a pseudo-haptic UI based on physical metaphors. The results show that the pseudo-haptic UI performs better in t…