2,992 research outputs found
Expressing Privacy Preferences in terms of Invasiveness
Dynamic context aware systems need highly flexible privacy protection mechanisms. We describe an extension to an existing RBAC-based mechanism that utilises a dynamic measure of invasiveness to determine whether contextual information should be released
Alternative Archaeological Representations within Virtual Worlds
Traditional VR methods allow the user to tour and view the virtual world from different perspectives. Increasingly, more interactive and adaptive worlds are being generated, potentially allowing the user to interact with and affect objects in the virtual world. We describe and compare four models of operation that allow the publisher to generate views, with the client manipulating and affecting specific objects in the world. We demonstrate these approaches through a problem in archaeological visualization
Documenting and validating Virtual Archaeology
The use of Virtual Archaeology is expanding rapidly, not only in the museum and archaeology professions, but also in the broadcast media, tourism and heritage industries. Many concerns have been expressed about the lack of transparency and difficulty in validating the models and presentations used in these contexts. A case study is used to illustrate the role of metadata in addressing these problems. The paper argues that appropriate metadata documentation of projects may extend the critical apparatus that we take for granted in scientific papers into the world of distributed Virtual Archaeology. Three recently introduced XML languages for multimedia (SMIL), vector graphics (SVG) and virtual reality (X3D) applications are examined with particular reference to their metadata hosting capabilities. Finally, an outline proposal for a Virtual Archaeology Metadata Profile and Schema is presented, based on refinements of the Dublin Core and other metadata schemas
Capturing Regular Human Activity through a Learning Context Memory
A learning context memory consisting of two main parts is
presented. The first part performs lossy data compression,
keeping the amount of stored data at a minimum by combining
similar context attributes â the compression rate for the
presented GPS data is 150:1 on average. The resulting data is
stored in an appropriate data structure highlighting the level
of compression. Elements with a high level of compression
are used in the second part to form the start and end points
of episodes capturing common activity consisting of consecutive
events. The context memory is used to investigate how
little context data can be stored containing still enough information
to capture regular human activity
Gapless topological phases and symmetry-enriched quantum criticality
We introduce topological invariants for critical bosonic and fermionic
chains. More generally, the symmetry properties of operators in the low-energy
conformal field theory (CFT) provide discrete invariants, establishing the
notion of symmetry-enriched quantum criticality. For nonlocal operators, these
invariants are topological and imply the presence of localized edge modes.
Depending on the symmetry, the finite-size splitting of this topological
degeneracy can be exponential or algebraic in system size. An example of the
former is given by tuning the spin-1 Heisenberg chain to an Ising phase. An
example of the latter arises between the gapped Ising and cluster phases: this
symmetry-enriched Ising CFT has an edge mode with finite-size splitting . More generally, our formalism unifies various examples previously
studied in the literature. Similar to gapped symmetry-protected topological
phases, a given CFT can split into several distinct symmetry-enriched CFTs.
This raises the question of classification, to which we give a partial
answer---including a complete characterization of symmetry-enriched Ising CFTs.Comment: 18 pages + appendi
Subspecies Composition, Genetic Variation and Structure of Largemouth Bass in Puerto Rico Reservoirs
Subspecies composition and genetic variation are important to the growth and survival of Largemouth Bass and information on these genetic characteristics is required for proper management of the species. In Puerto Rico, a genetic evaluation is needed to develop management plans for Puerto Rico reservoirs and maintain Florida Largemouth Bass at the Maricao Hatchery. Subspecies composition was characterized among reservoirs and the contemporary Maricao Hatchery broodstock in Puerto Rico, and metrics were compared between subspecies and hybrids among reservoir populations. Genetic variation and structure was determined and compared to Largemouth Bass populations in their native range. Florida subspecies were prevalent in all populations and non-introgressed subspecies seemed to be better adapted to the island than introgressed forms. Genetic diversity was lower in Puerto Rico populations and substantial genetic structure among populations was lacking. These results provide genetic information to guide future management and propagation of Largemouth Bass in Puerto Rico
Subspecies Composition, Genetic Variation and Structure of Largemouth Bass in Puerto Rico Reservoirs
Subspecies composition and genetic variation are important to the growth and survival of Largemouth Bass and information on these genetic characteristics is required for proper management of the species. In Puerto Rico, a genetic evaluation is needed to develop management plans for Puerto Rico reservoirs and maintain Florida Largemouth Bass at the Maricao Hatchery. Subspecies composition was characterized among reservoirs and the contemporary Maricao Hatchery broodstock in Puerto Rico, and metrics were compared between subspecies and hybrids among reservoir populations. Genetic variation and structure was determined and compared to Largemouth Bass populations in their native range. Florida subspecies were prevalent in all populations and non-introgressed subspecies seemed to be better adapted to the island than introgressed forms. Genetic diversity was lower in Puerto Rico populations and substantial genetic structure among populations was lacking. These results provide genetic information to guide future management and propagation of Largemouth Bass in Puerto Rico
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