Intelligent Transportation systems are characterised by a requirement for detailed information on extensive transport networks. This information is typically gathered from sensors deployed throughout the network and i...
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Intelligent Transportation systems are characterised by a requirement for detailed information on extensive transport networks. This information is typically gathered from sensors deployed throughout the network and is used for management and maintenance operations. In this paper we present the design and prototype implementation of a context-aware route profiling application intended for use by road management authorities in the Republic of Ireland. Our design allows data from a variety of sources to be combined to generate detailed information on traffic flow and journey times along the national road network. This information can be tagged with relevant context data reflecting the conditions under which sensor data was collected. The set of relevant contextual information includes details on temporal, spatial, weather and road usage pattern contexts. The prototype implementation relies on GPS data from a fleet of probe vehicles. An evaluation of this prototype is presented along with a discussion on the benefits of using context-aware computing techniques in a real world scenario.
Applications of inter-vehicle and vehicle-to-roadside communication that make use of vehicular ad hoc networks (VANETs) will often require reliable communication that provides guaranteed real-time message propagation....
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ISBN:
(纸本)1581139225
Applications of inter-vehicle and vehicle-to-roadside communication that make use of vehicular ad hoc networks (VANETs) will often require reliable communication that provides guaranteed real-time message propagation. This paper describes an event-based middleware, called RT-STEAM. Unlike other event systems, RT-STEAM does not rely on a centralized event broker or look-up service while still supporting event channels providing hard real-time event delivery. RT-STEAM event filtering can be based on subject, content and/or proximity. To guarantee real-time communication, we exploit proximity-based event propagation to guarantee real-time constraints within the defined proximities only. The proximity within which real-time guarantees are available is adapted to maintain time bounds while allowing changes to membership and topology, typical of VANETs. This Space-Elastic Model of real-time communication is the first to directly address adaptation in the space domain to guarantee real-time constraints.
Agile processes such as XP (eXtreme Programming) have been recognised for their potential benefits of improving software. During adoption of the XP process, teams can misapply the XP principles by following them verba...
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Some concerns, such as debugging or logging functionality, cannot be captured cleanly, and are often tangled and scattered throughout the code base. These concerns are called crosscutting concerns. Aspect-Oriented Pro...
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ISBN:
(纸本)076952124X
Some concerns, such as debugging or logging functionality, cannot be captured cleanly, and are often tangled and scattered throughout the code base. These concerns are called crosscutting concerns. Aspect-Oriented Programming (AOP) is a paradigm that enables developers to capture crosscutting concerns in separate aspect modules. The use of aspects has been shown to improve understandability and maintainability of systems. It has been shown that real-time concerns, such as memory management and thread scheduling, are crosscutting concerns [5, 6, 9, 11]. However it is unclear whether encapsulating these concerns provides benefits. We were interested in determining whether using AOP to encapsulate real-time crosscutting concerns afforded benefits in system properties such as understandability and maintainability. This paper presents research comparing the system properties of two systems: a real-time sentient traffic simulator and its Aspect-Oriented equivalent. An evaluation of AOP is presented indicating both benefits and drawbacks with this approach.
The objective of the 13th edition of Ph Doctoral Students in Object-Oriented systems workshop (PHDOOS) was to offer an opportunity for PhD students to meet and share their research experiences, and to discover commona...
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Today's markets are characterized by increasing turbulence, which forces industrial companies world wide to become more and more flexible. This flexibility is needed in all levels of industry and especially within...
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To achieve Quality of Service (QoS) in Next Generation Networks (NGNs), the Differentiated Services architecture implements appropriate Per Hop Behavior (PHB) for service differentiation. Common recommendations to enf...
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Peer-to-Peer (P2P) computing is said to be the next wave of computing after client-server and web-based computing. It provides an opportunity to harness a lot of idle peer-resources such as desktop computers across th...
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While the use of network intrusion detection systems (nIDS) is becoming pervasive, evaluating nIDS performance has been found to be challenging. The goal of this study is to determine how to generate realistic workloa...
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ISBN:
(纸本)1581136730
While the use of network intrusion detection systems (nIDS) is becoming pervasive, evaluating nIDS performance has been found to be challenging. The goal of this study is to determine how to generate realistic workloads for nIDS performance evaluation. We develop a workload model that appears to provide reasonably accurate estimates compared to real workloads. The model attempts to emulate a traffic mix of different applications, reflecting characteristics of each application and the way these interact with the system. We have implemented this model as part of a traffic generator that can be extended and tuned to reflect the needs of different scenarios. We also present an approach to measuring the capacity of a nIDS that does not require the setup of a full network testbed. security, intrusion detection, workload characterization and generation.
Adaptivity is a key issue for enhanced multimedia communication in wireless environments, where the network QoS for a whole session cannot be guaranteed. Within this paper we propose a set of mechanisms to provide ada...
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Adaptivity is a key issue for enhanced multimedia communication in wireless environments, where the network QoS for a whole session cannot be guaranteed. Within this paper we propose a set of mechanisms to provide adaptive multimedia multi-party communication according to user-defined QoS levels over self-organizing ad hoc network extensions connected to IP access networks. We use special extensions to SIP/SDPng based on XML to negotiate alternative application defined QoS levels and adaptation paths and optionally couple local resource management with network layer QoS. At the network layer, we propose the MMARP (Multicast MANET Routing Protocol) which provides efficient multicast communications within ad hoc network extension to public infrastructure based access networks. MMARP is able to deal with the complexity of supporting traditional IP nodes whilst inter-operating smoothly with fixed IP networks. An adaptive application architecture is demonstrated that uses the E2ENP and allows multimedia applications to reconfigure themselves in real-time to match the specific network conditions in order to preserve the user-perceived QoS. Thus, an integration of application layer QoS as defined by the user and network layer QoS is achieved.
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