Virtual environment trajectory analysis:a basis for navigational assistance and scene adaptivity

This paper describes the analysis and clustering of motion trajectories obtained while users navigate within a virtual environment (VE). It presents a neural network simulation that produces a set of five clusters which help to differentiate users on the basis of efficient and inefficient navigational strategies. The accuracy of classification carried out with a self-organising map algorithm was tested and improved to in excess of 85% by using learning vector quantisation. This paper considers how such user classifications could be utilised in the delivery of intelligent navigational support and the dynamic reconfiguration of scenes within such VEs. We explore how such intelligent assistance and system adaptivity could be delivered within a Multi-Agent Systems (MAS) context

Repurposing resources as open content: studying the experiences of new providers

Much educational content sits within institutional systems protected from global access, this proprietary approach restricts opportunities for informal learning and the exchange of materials between cultures. One response to reducing this particular digital divide is to open up access to existing courses by providing them as free to use Open Educational Resources (OERs). This is being addressed through work on OpenLearn (the open content initiative from The Open University developed with support from the William and Flora Hewlett Foundation) and POCKET (The Project on Open Content for Knowledge Exposition and Teaching, supported by JISC under the repositories and preservation programme). The approach is evaluative considering transfer of lessons from work on the reworking of distance learning materials (within the OpenLearn initiative) to the reworking of material from campus-based universities (supported by the POCKET project). Analysis will include the role of supporting artifacts (guidelines, examples, tools) and the process support required (shared aims, workshops, structure). Evaluation tools that are being applied include logging of experience, stake holder interviews, and analytics data. We are building on existing evaluation of the OpenLearn initiative that has revealed models for learner use of open educational resources and studied the reuse of released open resources. Results include the need for a range of reworkable formats, support and time pressures on voluntary use – these results are supported by case study information and overall usage statistics. Further data that will be available from POCKET by September 2008 will include reflections from participants, workshop outcomes and initial stakeholder interviews, full evaluation of POCKET will be complete by April 2009. This paper will have examined our understanding of the process by which content can be transformed from existing learning materials to freely available open educational resources. Conclusions at this stage will focus on the process of adoption and transfer from OpenLearn and the effectiveness of the evaluation and project approach. Comparison will be made with the advantages and disadvantages of the self supported approach adopted initially in OpenLearn and suggestions given for structures that enable collaboration in producing open educational resources

Two-dimensional Ising model with competing interactions and its application to clusters and arrays of π\pi-rings and adiabatic quantum computing

We study planar clusters consisting of loops including a Josephson $\pi$-junction ($\pi$-rings). Each $\pi$-ring carries a persistent current and behaves as a classical orbital moment. The type of particular state associated with the orientation of orbital moments at the cluster depends on the interaction between these orbital moments and can be easily controlled, i.e. by a bias current or by other means. We show that these systems can be described by the two-dimensional Ising model with competing nearest-neighbor and diagonal interactions and investigate the phase diagram of this model. The characteristic features of the model are analyzed based on the exact solutions for small clusters such as a 5-site square plaquette as well as on a mean-field type approach for the infinite square lattice of Ising spins. The results are compared with spin patterns obtained by Monte Carlo simulations for the 100 $\times$ 100 square lattice and with experiment. We show that the $\pi$-ring clusters may be used as a new type of superconducting memory elements. The obtained results may be verified in experiments and are applicable to adiabatic quantum computing where the states are switched adiabatically with the slow change of coupling constants.Comment: 32 pages, 22 figures, RevTe

Presence and task performance:an approach in the light of cognitive style

The paper highlights the relationship between each of four bi-polar dimensions of personality cognitive style, such as extraversion–introversion, sensing–intuition, thinking–feeling and judging–perceiving, and the level of sense of presence experienced. Findings indicate that individuals who are more sensitive, more feeling or more introverted experience a higher level of presence. While not reaching statistical significance, differing cognitive styles appear to impact on task performance. The apparent negative relationship discovered between sense of presence and task performance should be considered in the light of task characteristics. We discuss the implications of these findings and how they contribute to an understanding of the complex relationship that exists between presence and task performance and how this subsequently ought to influence the design of virtual environments

Content vs. context for multimedia semantics: the case of SenseCam image structuring

Much of the current work on determining multimedia semantics from multimedia artifacts is based around using either context, or using content. When leveraged thoroughly these can independently provide content description which is used in building content-based applications. However, there are few cases where multimedia semantics are determined based on an integrated analysis of content and context. In this keynote talk we present one such example system in which we use an integrated combination of the two to automatically structure large collections of images taken by a SenseCam, a device from Microsoft Research which passively records a person’s daily activities. This paper describes the post-processing we perform on SenseCam images in order to present a structured, organised visualisation of the highlights of each of the wearer’s days

Early neoproterozoic marine redox conditions recorded in black shale from the little Dal Group, Northwest Territories, Canada

Black shale in the Little Dal Group (ca. <817 Ma), Mackenzie Mountains Supergroup (779 Ma), was deposited during the early Neoproterozoic, and is one of the few known black shale deposits from this crucial time in Earth’s evolutionary history. Relative iron enrichment (FeT/Al) and conventional iron speciation (DOP), along with enrichment in molybdenum, total sulphur, and total organic carbon, were studied. Iron systematics (FeT/Al >0.5 and DOP <0.80) indicate ferruginous, anoxic, and possibly oxic bottom-water conditions over the time of deposition of the entire black shale unit. The enrichment factors of several of the authigenic redox-sensitive trace elements (U, Mo, V) are strongly correlated, and appear to be related to both the FeT and the organic carbon content of the black shale. Molybdenum enrichment (<10 ppm) is limited, which is in very good agreement with data from Mesoproterozoic black shales, but is much lower than Mo enrichments in Paleozoic black shales (typically >100 ppm). Several black muddy siltstones yielded similar results, but authigenic iron was greatly overwhelmed by siliciclastic sedimentation. These new data support the theory that ocean bottom-waters returned from sulphidic to ferruginous prior to development of oxygenated conditions in the Ediacaran open ocean. This study documents a predominantly open-marine basin that was characterised by ferruginous conditions, similar to Archean and early Paleoproterozoic conditions, with brief intervals when oxic conditions developed.Master'

Who Lives in Hard-to-Count Neighborhoods

For more than 20 years the U.S. Census Bureau has engaged in work to identify local areas that are likely to be difficult to enumerate in the Decennial Census. Such areas have been labeled “Hard-to-count.” In this study I use the final Mail Return Rates from the 2010 Census to identify a group of Census Tracts that I label Hard-to-Count or HTC. Once HTC Tracts have been identified I examine the demographic characteristics and socioeconomic characteristics of the population living in the HTC Tracts and compare them the population in all Tracts. Demographic characteristics of the HTC Tracts examined here include location, age, race, and sex, along with several socioeconomic measures such as poverty and living arrangements. The distribution of characteristics for the population residing in the HTC Census Tracts is compared to the distribution for all Tracts to develop a HTC concentration ratio. The HTC Tracts are highly concentrated geographically. The 25 counties with the most HTC Tracts account for half of all HTC Tracts. Blacks, Hispanics and American Indian populations are highly concentrated in HTC Tracts. Demographic groups with the highest concentration in HTC Tracts are identified and the net undercount rates for these groups are examined. The relationship between concentration in HTC neighborhoods and Census undercount rates is mixed

Geographic Variation in 2010 U.S. Census Coverage Rates for Young Children: A Look at Counties

Data from the Census Bureau’s Demographic Analysis (DA) show there was a net undercount of almost one million children under age 5 in the 2010 Decennial Census. The net undercount for young children was more than twice as high as any other age group. Given the high net total undercount of young children it would be useful to know how this net undercount is distributed geographically. In this study, the 2010 Decennial Census county-level counts of children age 0 to 4 are compared to corresponding figures from the Census Bureau’s Vintage 2010 population estimates, to ascertain census coverage for young children. Results show that net undercount rates for young children are higher in larger counties and counties with high percentages of Black or Hispanic children but county growth rates do not seem to be related to net undercount rates for young children. Discussion explores how this information may be helpful in the 2020 Census