Robust execution of service workflows using redundancy and advance reservations

In this paper, we develop a novel algorithm that allows service consumers to execute business processes (or workflows) of interdependent services in a dependable manner within tight time-constraints. In particular, we consider large inter-organisational service-oriented systems, where services are offered by external organisations that demand financial remuneration and where their use has to be negotiated in advance using explicit service-level agreements (as is common in Grids and cloud computing). Here, different providers often offer the same type of service at varying levels of quality and price. Furthermore, some providers may be less trustworthy than others, possibly failing to meet their agreements. To control this unreliability and ensure end-to-end dependability while maximising the profit obtained from completing a business process, our algorithm automatically selects the most suitable providers. Moreover, unlike existing work, it reasons about the dependability properties of a workflow, and it controls these by using service redundancy for critical tasks and by planning for contingencies. Finally, our algorithm reserves services for only parts of its workflow at any time, in order to retain flexibility when failures occur. We show empirically that our algorithm consistently outperforms existing approaches, achieving up to a 35-fold increase in profit and successfully completing most workflows, even when the majority of providers fail

A Formal Semantic Model of the Semantic Web Service Ontology (WSMO)

Semantic Web Services, one of the most significant research areas within the Semantic Web vision, has attracted increasing attention from both the research community and industry. The Web Service Modelling Ontology (WSMO) has recently been proposed as an enabling framework for the total/partial automation of the tasks (e.g., discovery, selection, composition, mediation, execution, monitoring, etc.) involved in both intra- and inter-enterprise integration of Web Services. To support the standardization and tool support of WSMO, a formal semantics of the language is highly desirable. As there are a few variants of WSMO and it is still under development, the semantics of WSMO needs to be formally defined to facilitate easy reuse and future development. In this paper, we present a formal Object-Z semantics of WSMO. Different aspects of the language have been precisely defined within one unified framework. This model not only provides a formal unambiguous model which can be used to develop tools and facilitate future development, but as demonstrated in this paper, can be used to identify and eliminate errors presented in existing documentation

Transitioning Applications to Semantic Web Services: An Automated Formal Approach

Semantic Web Services have been recognized as a promising technology that exhibits huge commercial potential, and attract significant attention from both industry and the research community. Despite expectations being high, the industrial take-up of Semantic Web Service technologies has been slower than expected. One of the main reasons is that many systems have been developed without considering the potential of the web in integrating services and sharing resources. Without a systematic methodology and proper tool support, the migration from legacy systems to Semantic Web Service-based systems can be a very tedious and expensive process, which carries a definite risk of failure. There is an urgent need to provide strategies which allow the migration of legacy systems to Semantic Web Services platforms, and also tools to support such a strategy. In this paper we propose a methodology for transitioning these applications to Semantic Web Services by taking the advantage of rigorous mathematical methods. Our methodology allows users to migrate their applications to Semantic Web Services platform automatically or semi-automatically

A Formal Model of Semantic Web Service Ontology (WSMO) Execution

Semantic Web Services have been one of the most significant research areas within the Semantic Web vision, and have been recognized as a promising technology that exhibits huge commercial potential. Current Semantic Web Service research focuses on defining models and languages for the semantic markup of all relevant aspects of services, which are accessible through a Web service interface. The Web Service Modelling Ontology (WSMO) is one of the most significant Semantic Web Service framework proposed to date. To support the standardization and tool support of WSMO, a formal semantics of the language is highly desirable. As there are a few variants of WSMO and it is still under development, the semantics of WSMO needs to be formally defined to facilitate easy reuse and future development. In this paper, we present a formal Object-Z semantics of WSMO. Different aspects of the language have been precisely defined within one unified framework. This model provides a formal unambiguous specification, which can be used to develop tools and facilitate future development

General Aviation Land Use Planning

In this session we discuss the value of land use planning sessions in determining airside and landside short-, mid-, and long-term needs of the airport. Land use plans have been used to secure funding and increase commercial landside and military airside growth. Currently a plan is being used to develop the first general aviation aerotropolis concept. Join us to learn how a land use plan can increase the marketability and revenue generation of your airport

DISCUS: the distributed core for ubiquitous broadband access

A new end to end architecture based on Long-Reach Passive Optical Network (LR-PON) with wireless integration, a distributed core built of optical transparency islands and an OpenFlow-based control plane, which is being developed in the EU project DISCUS, is described in this paper. The main technological advances and the network modelling and optimization approach are reported

Endoscopic urethrotomy versus open urethroplasty for men with bulbar urethral stricture : the OPEN randomised trial cost-effectiveness analysis

Funding: Funding for this study was provided by the Health Technology Assessment programme of the National Institute for Health Research, ref: 10/57/23. Acknowledgements: Contributors: Jing Shen, supervised by Luke Vale, led the health economic evaluation and analysis. Robert Pickard led the study, Beatriz Goulao supervised by Graeme MacLennan performed the statistical analysis, Sonya Carnell and Rebecca Forbes supported by Stephanie Currer and supervised by Jennifer Wilkinson managed the trial. John Norrie contributed to the funding application and statistical analysis plan. He also provided support to the statistical analysis team. Matt Breckons, supervised by Jing Shen, conducted a time trade off experiment reported separately. Paul Whybrow, supervised by Tim Rapley, carried out the qualitative research reported separately. Mark Forrest managed and maintained the trial database. Elaine McColl contributed to the funding application and protocol. Daniela Andrich, Anthony Mundy, James N’Dow and Stephen Payne provided clinician support to the funding application, acted as PIs at key sites. Stewart Barclay contributed a patient view to the trial, including the funding application, the protocol, and all aspects of the analysis. Jonathan Cook was involved in the design of the study and Nick Watkin co-wrote the funding application, contributed clinical insight to the trial management group. We thank the patients and health-care professionals for their participation in the study; Stewart Barclay, the patient and service user representative in the OPEN Trial Management Group; the Trial Steering committee members: Roger Kockelburg (chairperson), John Matthews, Alan McNeil, Howard Kynaston and Neil Campling; Data Monitoring Committee members: Gordon Murray (chairperson), Richard Martin and Thomas Pinkney. We also thank the following people who worked on the trial: Matthew Jackson, Research Fellow; Gladys McPherson, Data Manager; Lee Munro, Trial Manager; Rachel Stephenson, Trial Manager; Sue Tremble, Trial Manager; Robbie Brown, Trial Manager; Mark Deverill, Health Economist; Amy Collins, Project Secretary; Lavinia Miceli, Project Secretary; and Ann Payne, Project Secretary. Members of the Open Trial Group responsible for recruitment and who acted as principle investigators for their centres were: Trevor Dorkin, Freeman Hospital, Newcastle; Nick Watkin, St George’s Hospital, London; Anthony Mundy, University College London Hospitals NHS Foundation Trust, London; Paul Anderson, Russells Hall Hospital, Dudley; Suzie Venn, Queen Alexandra Hospital, Portsmouth; Ian Eardley, St James’s University Hospital, Leeds; Mr David Dickerson, Weston General Hospital, Westonsuper-Mare; Nikesh Thiruchelvam, Addenbrooke’s Hospital, Cambridge; Richard Inman and Chris Chapple, Royal Hallamshire Hospital, Sheeld; Andrew Baird, Aintree University Hospital NHS Foundation Trust, Liverpool; Andrew Sinclair, Stepping Hill Hospital, Stockport; Rajeshwar Krishnanm, Kent and Canterbury Hospital, Canterbury; Rowland Rees, University Hospital Southampton NHS Foundation Trust, Southampton; James N’dow, Aberdeen Royal Inrmary, Aberdeen; Bruce Montgomery, Frimley Park Hospital, Camberley; Michael Swinn, East Surrey Hospital, Redhill; Alastair Henderson and John Donohue, Maidstone Hospital, Maidstone; Suzie Venn, St Richard’s Hospital, Chichester; Robert Mason, Torbay Hospital, Torquay; Sanjeev Madaan, Darent Valley Hospital, Kent; Mustafa Hilmy, York Hospital, York; Vivienne Kirchin, Sunderland Royal Inrmary, Sunderland; Kim Davenport, Cheltenham General Hospital, Cheltenham; John McGrath, Exeter Hospital, Exeter; Tim Porter, Yeovil District Hospital, Yeovil; Ruaraidh MacDonagh and Amerdip Birring, Musgrove Park Hospital, Taunton; Ramachandran Ravi, Basildon University Hospital; Jawad Husain, Royal Albert Edward Inrmary, Wigan; Maj Shabbir, Guy’s Hospital, London; Omer Baldo, Airedale General Hospital, Keighley; Sadhanshu Chitale, Whittington Hospital, London; Mary Garthwaite, James Cook University Hospital, Middlesbrough; Shalom Srirangam, Royal Blackburn Hospital, Blackburn; Liaqat Chowoo, Bedford Hospital, Bedford; Tina Rashid, Charing Cross Hospital, London; Rob Skyrme; Jon Featherstone, Princess of Wales Hospital, Bridgend; Ammar Alhasso, Edinburgh; and Oleg Tatarov, Cardiff. We thank the following trusts for offering participant identication centre support: Basingstoke and Northamptonshire NHS Foundation Trust; Royal Liverpool and Broadgreen University Hospitals NHS Trust; Chelsea and Westminster NHS Foundation Trust; and Wirral University Teaching Hospital NHS Foundation Trust. We thank the following Trusts for offering PIC support: Basingstoke and Northamptonshire NHS Foundation Trust; Royal Liverpool and Broadgreen University Hospitals NHS Trust; Chelsea and Westminster NHS Foundation Trust; Wirral University Teaching Hospitals NHS Foundation Trust.Peer reviewedPublisher PDFPublisher PD