Model Based Development of Quality-Aware Software Services

Modelling languages and development frameworks give support for functional and structural description of software architectures. But quality-aware applications require languages which allow expressing QoS as a first-class concept during architecture design and service composition, and to extend existing tools and infrastructures adding support for modelling, evaluating, managing and monitoring QoS aspects. In addition to its functional behaviour and internal structure, the developer of each service must consider the fulfilment of its quality requirements. If the service is flexible, the output quality depends both on input quality and available resources (e.g., amounts of CPU execution time and memory). From the software engineering point of view, modelling of quality-aware requirements and architectures require modelling support for the description of quality concepts, support for the analysis of quality properties (e.g. model checking and consistencies of quality constraints, assembly of quality), tool support for the transition from quality requirements to quality-aware architectures, and from quality-aware architecture to service run-time infrastructures. Quality management in run-time service infrastructures must give support for handling quality concepts dynamically. QoS-aware modeling frameworks and QoS-aware runtime management infrastructures require a common evolution to get their integration

Geo-visual analytics for urban design in the context of future Internet

The internet, where much of the information has reference to location, together with the latest generation of geographical web services, represent a very large information space that can be used for planning and design. The wealth of information accessible, which requires new forms of interaction and management of the data available, has brought in recent year to the growth of the domain of visual analytics. In addition, the availability of 3D geobrowsers provides the technological means for interactive 3D environments which can be used to access large-scale geographical information. This technological scenario is paving the way to 3D webbased, geo-visual analytics tools for land planning and urban design tools. This paper illustrates the results of a research effort which has brought to the development of an interactive geo-visual analytics platform for land planning and urban design which makes use of procedural modelling algorithms

Towards an aspect weaving BPEL engine

This position paper proposes the use of dynamic aspects and the visitor design pattern to obtain a highly configurable and extensible BPEL engine. Using these two techniques, the core of this infrastructural software can be customised to meet new requirements and add features such as debugging, execution monitoring, or changing to another Web Service selection policy. Additionally, it can easily be extended to cope with customer-specific BPEL extensions. We propose the use of dynamic aspects not only on the engine itself but also on the workflow in order to tackle the problems of Web Service hot deployment and hot fixes to long running processes. In this way, composing aWeb Service "on-the-fly" means weaving its choreography interface into the workflow

The LEAF Platform: Incremental Enhancements for the J2EE

LEAF, the Lean and Extensible Architectural Framework, is an enhancement wrapper for J2EE implementations. Basically, LEAF fixes some identified J2EE issues and extends, as well as simplifies, the use of the J2EE by providing several incremental improvements. These improvements are seamlessly integrated, include an additional component type, allow the same interfaces for local and remote service implementations, offer better J2EE implementation compatibility and ORB interceptors, and encompass several new technical services. This paper explains the need for LEAF through a diagnosis of the J2EE, presents the fundamental concepts underlying LEAF, overviews its implementation, reports on field experiences from using it in a number of commercial projects, and points out some interesting tradeoffs in using the J2EE with and without LEAF

Customizing Component Middleware for Distributed Real-Time Systems with Aperiodic and Periodic Tasks

Many distributed real-time applications must handle mixed aperiodic and periodic tasks with diverse requirements. However, existing middleware lacks flexible configuration mechanisms needed to manage end-to-end timing easily for a wide range of different applications with both aperiodic and periodic tasks. The primary contribution of this work is the design, implementation and performance evaluation of the first configurable component middleware services for admission control and load balancing of aperiodic and periodic tasks in distributed real-time systems. Empirical results demonstrate the need for, and the effectiveness of, our configurable component middleware approach in supporting different applications with aperiodic and periodic tasks

Roadmap Analysis of Protein-Protein Interactions. Master\u27s Thesis, August 2007

The ability to effectively model the interaction between proteins is an important and open problem. In molecular biology it is well accepted that from sequence arises form and from form arises function but relating structure to function remains a challenge. The function of a given protein is defined by its interactions. Likewise a malfunction or a change in protein-protein interactions is a hallmark of many diseases. Many researchers are studying the mechanisms of protein-protein interactions and one of the overarching goals of the community is to predict whether two proteins will bind, and if so what the final conformation will be. Attention is seldom paid to the association pathways that allow two proteins to bind. Evidence has shown that the information in the association pathways can play a vital role in understanding the interaction itself. This thesis presents a novel and scalable approach to computing association pathways between two proteins using the Probabilistic Roadmap (PRM) framework. We will discuss the challenges in extending PRM to the domain of protein-protein interactions such as performing structural mappings in a reduced space of flexibility, and sampling high dimensional conformation spaces. We will present analysis of individual association pathways as well as methods for estimating collective properties of the energy landscape. Our results indicate that these methods can discriminate between true and false protein binding interfaces. Finally, we will present condensing methods such as pathway clustering and visualization using dimensionality reduction that can be be applied to create compact representations of the interaction space

Reconfigurable Real-Time Middleware for Distributed Cyber-Physical Systems with Aperiodic Events

Different distributed cyber-physical systems must handle aperiodic and periodic events with diverse requirements. While existing real-time middleware such as Real-Time CORBA has shown promise as a platform for distributed systems with time constraints, it lacks flexible configuration mechanisms needed to manage end-to-end timing easily for a wide range of different cyber-physical systems with both aperiodic and periodic events. The primary contribution of this work is the design, implementation and performance evaluation of the first configurable component middleware services for admission control and load balancing of aperiodic and periodic event handling in distributed cyber-physical systems. Empirical results demonstrate the need for, and the effectiveness of, our configurable component middleware approach in supporting different applications with aperiodic and periodic events, and providing a flexible software platform for distributed cyber-physical systems with end-to-end timing constraints

Challenges for the comprehensive management of cloud services in a PaaS framework

The 4CaaSt project aims at developing a PaaS framework that enables flexible definition, marketing, deployment and management of Cloud-based services and applications. The major innovations proposed by 4CaaSt are the blueprint and its lifecycle management, a one stop shop for Cloud services and a PaaS level resource management featuring elasticity. 4CaaSt also provides a portfolio of ready to use Cloud native services and Cloud-aware immigrant technologies

Monitoring middleware for distributed applications

With growing maturity Internet services are proving integral to the provision of computer services. To provide consistent end-user experiences these services are increasingly augmented with some notion of 'Quality-of-Service' (QoS), which typically requires the management of computing resources to maintain a predictable level of service performance. It is difficult to guarantee consistent servIce provision In dynamic and open environments such as the Internet. However service monitoring can be used to inform compensatory actions by collecting meaningful service performance data from strategic points in an active service environment. Due to the unpredictable nature of the Internet distributed monitoring mechanisms face challenges with respect to the various communication protocols, application languages, and monitoring requirements associated with a service environment. With the growing popularity of Internet services creation of monitoring solutions on a per- service basis becomes time-consuming and misses opportunities to re-use existing logic. Ideally monitoring solutions would be domain-agnostic, automatically generated and automatically deployed. This thesis progresses these ambitions by providing a generic, distributed monitoring and evaluation framework based on Metric Collector (MeCo) components. These components can transparently gather measurement data across a range of service technologies as used within E-Commerce service environments. MeCo components form part of a framework which can interpret Service Level Agreements (SLAs) to automatically provide tailored service monitoring. The evaluation paradigms of the Meeo Framework are re-appropriated for use in Distributed Virtual Environments (DYEs). Quantifiable QoS requirements are established for Interest Management mechanisms (which limit message production based on object localities within a DYE). These are then incorporated into a DVE Simulator application. This application allows DYE application developers to evaluate Interest Management configurations for their suitability. Extensions to the DVE Simulator are exhibited in the Evolutionary Optimisation Simulator (EOS), which provides automated optimisation capabilities for DVE configurations through utilisation of genetic algorithm techniques.EThOS - Electronic Theses Online ServiceGBUnited Kingdo