Interaction of marine geodesy, satellite technology and ocean physics

The possible applications of satellite technology in marine geodesy and geodetic related ocean physics were investigated. Four major problems were identified in the areas of geodesy and ocean physics: (1) geodetic positioning and control establishment; (2) sea surface topography and geoid determination; (3) geodetic applications to ocean physics; and (4) ground truth establishment. It was found that satellite technology can play a major role in their solution. For solution of the first problem, the use of satellite geodetic techniques, such as Doppler and C-band radar ranging, is demonstrated to fix the three-dimensional coordinates of marine geodetic control if multi-satellite passes are used. The second problem is shown to require the use of satellite altimetry, along with accurate knowledge of ocean-dynamics parameters such as sea state, ocean tides, and mean sea level. The use of both conventional and advanced satellite techniques appeared to be necessary to solve the third and fourth problems

CliqueStream: an efficient and fault-resilient live streaming network on a clustered peer-to-peer overlay

Several overlay-based live multimedia streaming platforms have been proposed in the recent peer-to-peer streaming literature. In most of the cases, the overlay neighbors are chosen randomly for robustness of the overlay. However, this causes nodes that are distant in terms of proximity in the underlying physical network to become neighbors, and thus data travels unnecessary distances before reaching the destination. For efficiency of bulk data transmission like multimedia streaming, the overlay neighborhood should resemble the proximity in the underlying network. In this paper, we exploit the proximity and redundancy properties of a recently proposed clique-based clustered overlay network, named eQuus, to build efficient as well as robust overlays for multimedia stream dissemination. To combine the efficiency of content pushing over tree structured overlays and the robustness of data-driven mesh overlays, higher capacity stable nodes are organized in tree structure to carry the long haul traffic and less stable nodes with intermittent presence are organized in localized meshes. The overlay construction and fault-recovery procedures are explained in details. Simulation study demonstrates the good locality properties of the platform. The outage time and control overhead induced by the failure recovery mechanism are minimal as demonstrated by the analysis.Comment: 10 page

Rates of adoption in a university course management system

This research focuses on diffusion of an education innovation in a large, traditional University. In March 1999, the Blackboard digital course management system was installed for enterprise-wide availability at Temple University, the 39th largest university in the United States. The web-enabled database of Temple Blackboard logs the adoption date, course ID, and course title for every Blackboard course, unobtrusively, twenty-four hours a day. Temple Blackboard serves as 4 digital approximation of the cumulative recorder pioneered by B. F. Skinner, recording more than 2800 course adoptions across 30 months, in real time. Temple Blackboard course records provide unprecedented quantity and quality of objective measures of innovation diffusion in a large education organization. The whole population of digital cumulative records may be analyzed, making statistical sampling optional. Digital cumulative recording of Temple Blackboard course adoption facilitates comparisons with other Temple course management systems, while reducing pro-innovation bias. Blackboard dates of adoption for Temple University as a whole, per college, per department, and per faculty may be visualized, compared, ranked, and analyzed, answering pressing questions about educational technology diffusion with precision and economy

A review of climate change and the implementation of marine biodiversity legislation in the United Kingdom

1. Marine legislation, the key means by which the conservation of marine biodiversity is achieved, has been developing since the 1960s. In recent decades, an increasing focus on ‘holistic’ policy development is evident, compared with earlier ‘piecemeal’ sectoral approaches. Important marine legislative tools being used in the United Kingdom, and internationally, include the designation of marine protected areas and the Marine Strategy Framework Directive (MSFD) with its aim of meeting ‘Good Environmental Status’ (GES) for European seas by 2020. 2. There is growing evidence of climate change impacts on marine biodiversity, which may compromise the effectiveness of any legislation intended to promote sustainable marine resource management. 3. A review of key marine biodiversity legislation relevant to the UK shows climate change was not considered in the drafting of much early legislation. Despite the huge increase in knowledge of climate change impacts in recent decades, legislation is still limited in how it takes these impacts into account. There is scope, however, to account for climate change in implementing much of the legislation through (a) existing references to environmental variability; (b) review cycles; and (c) secondary legislation and complementary policy development. 4. For legislation relating to marine protected areas (e.g. the EC Habitats and Birds Directives), climate change has generally not been considered in the site-designation process, or for ongoing management, with the exception of the Marine (Scotland) Act. Given that changing environmental conditions (e.g. rising temperatures and ocean acidification) directly affect the habitats and species that sites are designated for, how this legislation is used to protect marine biodiversity in a changing climate requires further consideration. 5. Accounting for climate change impacts on marine biodiversity in the development and implementation of legislation is vital to enable timely, adaptive management responses. Marine modelling can play an important role in informing management decisions

A proposed concept for a crustal dynamics information management network

The findings of a requirements and feasibility analysis of the present and potential producers, users, and repositories of space-derived geodetic information are summarized. A proposed concept is presented for a crustal dynamics information management network that would apply state of the art concepts of information management technology to meet the expanding needs of the producers, users, and archivists of this geodetic information

Mutually Adaptive Distributed Heterogeneous Agents for Data Classification

Efficient and effective data classification is one of the most fundamental problems of computer science due to a huge number of important applications. As such, there have been many models that are capable of doing some form of data classification using a large number of varied algorithms and architectures. However, few share properties that implicitly take advantage of the distributed environment where classification has its most potential. Therefore, to resolve this dilemma in this thesis a generic classification architecture com posed of mutually adaptive distributed heterogeneous agents was designed, implemented and experimentally analyzed. The system defined creates a multi-agent distributed ar chitecture whereby individual agents cooperate and collaborate with each other to autonomously perform classification on arbitrary data using a hierarchical paradigm. The main contributions of this work are the following: agents follow hierarchical pro cesses to form an organization which can autonomously train, test, assign and evaluate work of other agents. Through experimental analysis it was found that this design improves the classification accuracy relative to previously implemented classification algorithms and architectures. Furthermore this analysis shows that the generated architecture will au tonomously adapt to previously unlearned data and responds to failures with little or no degradation of classification quality

Techniques for Processing TCP/IP Flow Content in Network Switches at Gigabit Line Rates

The growth of the Internet has enabled it to become a critical component used by businesses, governments and individuals. While most of the traffic on the Internet is legitimate, a proportion of the traffic includes worms, computer viruses, network intrusions, computer espionage, security breaches and illegal behavior. This rogue traffic causes computer and network outages, reduces network throughput, and costs governments and companies billions of dollars each year. This dissertation investigates the problems associated with TCP stream processing in high-speed networks. It describes an architecture that simplifies the processing of TCP data streams in these environments and presents a hardware circuit capable of TCP stream processing on multi-gigabit networks for millions of simultaneous network connections. Live Internet traffic is analyzed using this new TCP processing circuit