A Trustworthy Approach to the Adaptive Composition of GeoServices

AbstractFor the automatic generation of geographical information service chain, this article defines the quality of service (QoS) metrics based on service response time, reliability, and matching degree, among others, and the error propagation model. Based on the semantic matching and trustworthiness assessment of the geographical information services, this article proposes a trustworthy adaptive composition framework and implementation algorithm for geographical information services, ensuring the composition of service chains to better meet various QoS constraints. The effectiveness of this approach is proven in the simulation experiments

Consistency of service composition

We address the problem of ensuring that, when an application executing a service binds to a service that matches required functional properties, both the application and the service can work together, i.e., their composition is consistent. Our approach is based on a component algebra for service-oriented computing in which the configurations of applications and of services are modelled as asynchronous relational nets typed with logical interfaces. The techniques that we propose allow for the consistency of composition to be guaranteed based on properties of service orchestrations (implementations) and interfaces that can be checked at design time, which is essential for supporting the levels of dynamicity required by run-time service binding. © 2012 Springer-Verlag Berlin Heidelberg

Ensuring Cyber-Security in Smart Railway Surveillance with SHIELD

Modern railways feature increasingly complex embedded computing systems for surveillance, that are moving towards fully wireless smart-sensors. Those systems are aimed at monitoring system status from a physical-security viewpoint, in order to detect intrusions and other environmental anomalies. However, the same systems used for physical-security surveillance are vulnerable to cyber-security threats, since they feature distributed hardware and software architectures often interconnected by ‘open networks’, like wireless channels and the Internet. In this paper, we show how the integrated approach to Security, Privacy and Dependability (SPD) in embedded systems provided by the SHIELD framework (developed within the EU funded pSHIELD and nSHIELD research projects) can be applied to railway surveillance systems in order to measure and improve their SPD level. SHIELD implements a layered architecture (node, network, middleware and overlay) and orchestrates SPD mechanisms based on ontology models, appropriate metrics and composability. The results of prototypical application to a real-world demonstrator show the effectiveness of SHIELD and justify its practical applicability in industrial settings

The effect of fire disturbance on bee community composition in oak savannah habitat in Southern Ontario, Canada

Determining how bee communities respond to environmental disturbance is crucial for ensuring that the pollination service that bees provide is sustained. Studies have reported that bee communities respond to environmental disturbance; however they have not experimentally tested whether environmental disturbances are important for maintaining bee diversity. Unlike other studies of the impact of fire upon bees, this thesis is based upon experimental tests. I investigate whether fire disturbance plays a significant role in maintaining bee community diversity and composition, and how individual species occupy various ages of post-burn habitat. Freshly burned (< 4 years since fire), intermediate burn (5-10 years since fire), mature burn (15-20 years since fire) and control (no fire) plots were used in two oak savannah remnants in Southern Ontario. Results show fire to be an important environmental disturbance for maintaining bee diversity in the temporal sense, as bee diversity was at its highest in intermediate age burns. Bee diversity increased significantly immediately post fire in fresh habitat but high diversity was short lived whereas mature site bee diversity declined over time. Rank abundance plots and community composition analyses revealed bee communities differed in species composition among replicates of the same age since fire within localities and over time. Bee communities within localities showed similarities in composition. Functional nesting guilds examined were solitary and social ground nesters, cavity nesters, Bombus spp. and cleptoparasites. The relative proportional abundance of species within functional nesting guilds also varied over time and burn site. An examination into how bee species within functional guilds occupy burned habitat indicated that bee species of the same functional guild occupy burned habitat differently. Occupancy modeling of the 12 most common bee species suggests the need for more thorough assessments of the ecologies of individual species in order to fully determine how bee communities respond to environmental disturbances

Administrative Management Capacity in Out-of-School Time Organizations: An Exploratory Study

Based on interviews with sixteen high-quality out-of-school time (OST) program providers, identifies the managerial and administrative needs of OST nonprofits such as financial and human resources management and information technology. Suggests solutions

Combining behavioural types with security analysis

Today's software systems are highly distributed and interconnected, and they increasingly rely on communication to achieve their goals; due to their societal importance, security and trustworthiness are crucial aspects for the correctness of these systems. Behavioural types, which extend data types by describing also the structured behaviour of programs, are a widely studied approach to the enforcement of correctness properties in communicating systems. This paper offers a unified overview of proposals based on behavioural types which are aimed at the analysis of security properties