Use of video shadow for small group interaction awareness on a large interactive display surface

This paper reports work done as part of the Large Interactive Display Surface (LIDS) project at the University of Waikato. One application of the LIDS equipment is distributed meeting support. In this context large display surfaces are used as shared workspaces by people at collaborating sites. A meeting with start with a shared presentation document, typically and agenda document with summary and detail on agenda items as required. During the meeting, annotations with be made on the shared document, and new pages will be added with notes and drawings. To prevent access collisions and generally mediate use of the shared space, mechanisms to provide awareness of actions of people at other sites are required. In our system a web camera is used to capture a low-resolution image of the person/people near the board on each side. Rather than transmit the image directly we computed a shadow/silhouette. The shadow is displayed behind other screen content. This provides awareness of position and impending write actions and allows intentional pointing to locations of the screen. It also has the advantage of being transmitted with low bandwidth, being relatively insensitive to low frame rates, and minimizing visual interference with substantive data being displayed on the screen

Lecture capture using large interactive display systems

There are various software technologies that allow capture and redelivery of lectures. Most of these technologies however rely on the use of proprietary software, often requiring extra efforts from the lecturer in terms of the initial preparation of the lecture material, or in editing and annotating after the lecture to make the material suitable for the students. To review the material students then require access to the proprietary software. This paper describes a system for the lightweight capture of lecture presentations, based on the use of a low-cost large interactive display surface, together with standard Microsoft PowerPoint™ presentation software. The captured version of the presentation includes the original lecture slides, graphical annotations made by the lecturer during the lecture, and the audio recording of the lecture; all saved as a PowerPoint file. In addition, the system adds some annotations and index slides to allow quick and easy access to different segments of the presentation. Presentations can be replayed in part or in full as required, preserving all of the content of the live lecture

Infectious Ideas: Modelling the Diffusion of Ideas Across Social Networks

Will the practice of collecting wild honey while wearing no clothes become a widespread practice in Zimbabwe? Or will beekeeping take over as the main way that people acquire honey? Both practices impact on forest resources; how can the foresters influence the uptake of these ideas? This paper describes an exploratory modelling study investigating how social network patterns affect the way ideas spread around communities. It concludes that increasing the density of social networks increases the spread of successful ideas whilst speeding the loss of ideas with no competitive advantage. Some different kinds of competitive advantage are explored in the context of forest management and rural extension

Bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow

Urbanisation alters landscapes, introduces wildlife to novel stressors, and fragments habitats into remnant ‘islands’. Within these islands, isolated wildlife populations can experience genetic drift and subsequently suffer from inbreeding depression and reduced adaptive potential. The Western tiger snake (Notechis scutatus occidentalis) is a predator of wetlands in the Swan Coastal Plain, a unique bioregion that has suffered substantial degradation through the development of the city of Perth, Western Australia. Within the urban matrix, tiger snakes now only persist in a handful of wetlands where they are known to bioaccumulate a suite of contaminants, and have recently been suggested as a relevant bioindicator of ecosystem health. Here, we used genome-wide single nucleotide polymorphism (SNP) data to explore the contemporary population genomics of seven tiger snake populations across the urban matrix. Specifically, we used population genomic structure and diversity, effective population sizes (Ne), and heterozygosity-fitness correlations to assess fitness of each population with respect to urbanisation. We found that population genomic structure was strongest across the northern and southern sides of a major river system, with the northern cluster of populations exhibiting lower heterozygosities than the southern cluster, likely due to a lack of historical gene flow. We also observed an increasing signal of inbreeding and genetic drift with increasing geographic isolation due to urbanisation. Effective population sizes (Ne) at most sites were small (< 100), with Ne appearing to reflect the area of available habitat rather than the degree of adjacent urbanisation. This suggests that ecosystem management and restoration may be the best method to buffer the further loss of genetic diversity in urban wetlands. If tiger snake populations continue to decline in urban areas, our results provide a baseline measure of genomic diversity, as well as highlighting which ‘islands’ of habitat are most in need of management and protection

Successful Completion of the JWST OGSE2 Cryogenic Test at JSC Chamber-A While Managing Numerous Challenges

The James Webb Space Telescope (JWST) Optical Telescope Element (OTE) assembly is the largest optically stable infrared-optimized telescope currently being manufactured and assembled, and scheduled for launch in 2018. The JWST OTE, including the primary mirrors, secondary mirror, and the Aft Optics Subsystems (AOS) are designed to be passively cooled and operate at near 45 degrees Kelvin. Due to the size of its large sunshield in relation to existing test facilities, JWST cannot be optically or thermally tested as a complete observatory-level system at flight temperatures. As a result, the telescope portion along with its instrument complement will be tested as a single unit very late in the program, and on the program schedule critical path. To mitigate schedule risks, a set of 'pathfinder' cryogenic tests will be performed to reduce program risks by demonstrating the optical testing capabilities of the facility, characterizing telescope thermal performance, and allowing project personnel to learn valuable testing lessons off-line. This paper describes the 'pathfinder' cryogenic test program, focusing on the recently completed second test in the series called the Optical Ground Support Equipment 2 (OGSE2) test. The JWST OGSE2 was successfully completed within the allocated project schedule while faced with numerous conflicting thermal requirements during cool-down to the final cryogenic operational temperatures, and during warm-up after the cryo-stable optical tests. The challenges include developing a pre-test cool-down and warm-up profiles without a reliable method to predict the thermal behaviors in a rarified helium environment, and managing the test article hardware safety driven by the project Limits and Constraints (L&C's). Furthermore, OGSE2 test included the time critical Aft Optics Subsystem (AOS), a part of the flight Optical Telescope Element that would need to be placed back in the overall telescope assembly integrations. The OGSE2 test requirements included the strict adherence of the project contamination controls due to the presence of the contamination sensitive flight optical elements. The test operations required close coordination of numerous personnel while they being exposed and trained for the 'final' combined OTE and instrument cryo-test in 2017. This paper will also encompass the OGSE2 thermal data look-back review

Mitigation Mechanisms Against the DAO Attack on the Routing Protocol for Low Power and Lossy Networks (RPL)

Destination Advertisement Objects (DAOs) are sent upward by RPL nodes toward the DODAG root, to build the downward routing paths carrying traffic from the root to its associated nodes. This routing mechanism can be exploited by a malicious node periodically transmitting a large volume of DAO messages towards its parent, which in turn will forward such messages to its own parent and so on, until they arrive at the Direction-Oriented Directed Acyclic Graph (DODAG) root. This ultimately results in a negative effect on network performance in terms of energy consumption, latency and reliability. The first objective of this paper is to evaluate the effect of such a DAO attack in the context of an RPL IoT network. In particular, identifying the particular performance metrics and network resources affected most greatly. The second objective is the proposal of mitigating security mechanisms in relation to DAO attacks and to evaluate their effectiveness. The simulation results have shown how the attack can damage the network performance by significantly increasing the DAO overhead and power consumption. It also demonstrated that the DAO attack affect the reliability of the downward traffic under specific conditions. The proposed mechanisms showed a good capacity in restoring the optimal performance of the network by up to 205%, 181%, 87% and 6%, in terms of overhead, latency, power consumption and packet delivery ratio respectively

Identifying complications requiring re-operation following primary hip or knee arthroplasty: a consecutive series of 98 patients

BackgroundThe number of hip and knee arthroplasties completed is expected to double over the next decade. In public hospitals, regular post-arthroplasty orthopaedic review has commonly occurred for the duration of a patient&rsquo;s life, which requires substantial outpatient resources. However, there is limited evidence regarding the utility of these reviews for identifying complications. The current study investigated when and where complications requiring re-operation were identified following primary hip or knee arthroplasty.MethodsThe medical records of all patients requiring re-operation for complications following primary hip arthroplasty (n&thinsp;=&thinsp;48, 2004 to 2015) or knee primary arthroplasty (n&thinsp;=&thinsp;50, 1998 to 2015) at a large regional health service were evaluated. Data were extracted by one of four investigators using a standardised electronic data extraction tool. Variables of interest included the health setting where the complication was initially identified, how long following the original operation the complication was identified and whether the complication was symptomatic.ResultsRoutine post-arthroplasty orthopaedic appointments identified 15 (15.3%) complications requiring re-operation; all were identified in the first-year post-surgery. For each complication identified in the first-year post-surgery, approximately 1000 orthopaedic outpatient appointments were required. After the first year, all complications were identified in Emergency Departments (n =&thinsp;30, 30.6%), General Practice (n =&thinsp;24, 24.5%) or non-routine orthopaedic outpatient appointments (n =&thinsp;19, 19.4%). All patients with complications reported symptoms.ConclusionsRoutine post-arthroplasty review appointments were an inefficient mechanism for identifying complications requiring re-operation more than one year following surgery. Public health services should consider assessing and redesigning post-arthroplasty review services to reduce the burden on patients and the demand for outpatient appointments.<br /

The use of a T-maze to measure cognitive–motor function in cats (Felis catus)

Few tests have been developed to test the cognitive and motor capabilities of domestic cats, in spite of the suitability of cats for specific studies of neuroanatomy, infectious diseases, development, aging, and behavior. The present study evaluated a T-maze apparatus as a sensitive and reliable measure of cognition and motor function of cats. Eighteen purpose-bred, specific-pathogen-free, male, neutered domestic shorthair cats (Felis catus), 1-2 years of age, were trained and tested to a T-maze protocol using food rewards. The test protocol consisted of positional discrimination training (left arm or right arm) to criterion followed by two discrimination reversal tests. The two reversal tests documented the ability of the subjects to respond to a new reward location, and switch arms of the T-maze. Data were collected on side preference, number of correct responses, and latency of responses by the subjects. Aided by a customized computer program (CanCog Technologies), data were recorded electronically as each cat progressed from the start box to the reward arm. The protocol facilitated rapid training to a high and consistent level of performance during the discrimination training. This learning was associated with a decrease in the latency to traverse the maze to a mean of 4.80 ± 0.87 s indicating strong motivation and consistent performance. When the rewarded side was reversed in the test phase, cats required more trials to reach criterion, as expected, but again showed reliable learning. The latency to reward in the first session of reversal increased 86% from the first to the last trial indicating that it may provide a useful index of cognitive processing. Latencies subsequently decreased as the new reversal paradigm was learned. This paradigm provides a relatively rapid and reliable test of cognitive motor performance that can be used in various settings for evaluation of feline cognitive and motor function