109 research outputs found
Benchmarking Workflow Discovery: A Case Study From Bioinformatics
No full textAutomation in science is increasingly marked by the use of workflow technology. The sharing of workflows through repositories supports the verifability, reproducibility and extensibility of computational experiments. However, the subsequent discovery of workflows remains a challenge, both from a sociological and technological viewpoint. Based on a survey with participants from 19 laboratories, we investigate current practices in workflow sharing, re-use and discovery amongst life scientists chiefly using the Taverna workflow management system. To address their perceived lack of effective workflow discovery tools, we go on to develop benchmarks for the evaluation of discovery tools, drawing on a series of practical exercises. We demonstrate the value of the benchmarks on two tools: one using graph matching, the other relying on text clustering
Discovering Scientific Workflows: The myExperiment Benchmarks
No full textAutomation in science is increasingly marked by the use of workflow technology. The sharing of workflows through publication mechanisms or repositories supports the verifiability, reproducibility and extensibility of computational experiments. However, the subsequent discovery of workflows remains a challenge, both from a technological and sociological viewpoint. We investigate current practices in workflow sharing, re-use and discovery amongst life scientists chiefly using the Taverna workflow management system. The study draws on two key sources: (i) a survey of researchers drawn from 19 research labs and (ii) an analysis of scientists’ behaviour on the myExperiment social network site, designed to encourage workflow exchange. The results reveal a multi-modal approach to workflow discovery, based on a mix of search on the content of the workflow and its situated context. We go on to develop a benchmark specifically for the evaluation of workflow discovery and to demonstrate it on two example approaches
myExperiment: Defining the Social Virtual Research Environment
No full textThe myExperiment Virtual Research Environment supports the sharing of research objects used by scientists, such as scientific workflows. For researchers it is both a social infrastructure that encourages sharing and a platform for conducting research, through familiar user interfaces. For developers it provides an open, extensible and participative environment. We describe the design, implementation and deployment of myExperiment and suggest that its four capabilities - research objects, social model, open environment and actioning research - are necessary characteristics of an effective Virtual Research Environment for e-research and open science
Recycling workflows and services through discovery and reuse
No full textScientific workflows are becoming a valuable tool for scientists to capture and automate e-Science procedures. Their success brings the opportunity to publish, share, reuse and re-purpose this explicitly captured knowledge. Within the myGrid project, we have identified key resources that can be shared including complete workflows, fragments of workflows and constituent services. We have examined the alternative ways that these resources can be described by their authors (and subsequent users) and developed a unified descriptive model to support their later discovery. By basing this model on existing standards, we have been able to extend existing Web service and Semantic Web service infrastructure whilst still supporting the specific needs of the e-Scientist. The myGrid components enable a workflow lifecycle that extends beyond execution to include the discovery of previous relevant designs, the reuse of those designs and their subsequent publication. Experience with example groups of scientists indicates that this cycle is valuable. The growing number of workflows and services mean more work is needed to support the user in effective ranking of search results and to support the re-purposing process. Copyright © 2006 John Wiley & Sons, Ltd
La Vita S. Rosaliae di van Dyck nella Biblioteca della Fondazione Sicilia
No full textThe essay examines the Vita S. Rosaliae, a very rare collection of engravings taken from drawings by Antoon van Dyck, identified by the author and Maria Concetta Di Natale in the Sicily Foundation Library during preparatory research for the realisation of the exhibition 'The Ecstasies of Saint Rosalie - Antoon van Dyck, Pietro Novelli, Mattia Preti, Luca Giordano'
Risico en Rendement in Balans voor Verzekeraars
No full textAntoon Pelsser (1968) is Head of the Asset-Liability Matching department of
ING-Insurance. The ALM department advises the board on the optimal asset
allocation to cover the insurance liabilities. The department is also responsible
for the calculation of market values and risk measures of insurance contracts.
He also holds a part-time position as Professor of Mathematical Finance at the
Econometric Institute at the Erasmus University in Rotterdam. His research
interests focus on pricing models for interest rate derivatives, the pricing of
insurance contracts and Asset-Liability Management of insurance contracts. He has
published in several academic journals including Finance and Stochastics, Journal
of Derivatives, European Journal of Operational Research and European Finance
Review. He is also author of the book Efficient Methods for Valuing Interest Rate
Derivatives, published by Springer Verlag.In this inaugural address Professor Pelsser investigates how one can strike a balance between investmens with a high expected return and high risk (e.g. stocks) versus low-risk investments with a low return (e.g.bonds). Using an example of a life-insurance company he shows in this
address how one can employ optimisation-techniques to make a trade-off between the desire to find an investment return as high as possible under the constraint that the insurance company should be able to meet its obligations to the policyholders under all economic circumstances
Antoon van den Wijngaerdes tekeningen van steden in de Nederlanden: Inventief geconstrueerde stadsgezichten voor Filips II
No full textViews of twelve cities in the Low Countries by the Flemish artist Antoon van den Wijngaerde (c. 1510-1571) have survived: Amsterdam, Brugge, Brussels, Damme, Dordrecht, Duinkerke, Gravelines, ’s-Hertogenbosch, Leuven, Mechelen, Sluis, and Utrecht. Van den Wijngaerde was known for his mastery of topographically accurate and beautiful depictions of cities. The artist entered the service of Philip II in 1557 and between 1557 and 1561 he produced panoramas of cities in the Low Countries for the Spanish king. Between 1562 and 1571 Van den Wijngaerde travelled the length and breadth of Spain, depicting over sixty Spanish cities using much the same techniques. In most Spanish cities the artist was able to make his sketches from a hill or mountain, where he had a good overall view. It was a different story in the Low Countries.So how did Van den Wijngaerde manage to render the Netherlandish cities, most of them located on flat land, as if seen from a high viewing point with a sweeping view of the city and surrounding landscape? Van den Wijngaerde followed a fixed routine in setting up his city views, but he also made clever use of the local situation. He seized on any high point outside the city and allowed that to determine his direction of view. When several preparatory studies were necessary, he preferred to make them all looking in the same direction: the city roofscape viewed from outside the city, prominent buildings viewed from the city outskirts, and the surrounding area from the highest point in the city. This resulted in city views that were effectively a composite of three preparatory studies. When the local situation did not favour this approach, Van den Wijngaerde looked for alternatives, such as preliminary studies from more than three viewing points. In determining the viewing points that Van den Wijngaerde adopted when drawing cities in the Low Countries, the author consulted the town plans drawn by Van den Wijngaerde’s contemporary Jacob van Deventer (c. 1500-1575).History, Form & Aesthetic
Workflow re-use and discovery in bioinformatics
No full textScientists in many disciplines are increasingly faced with analysing a deluge of scientific data from sources scattered across the globe. Workflow techniques have the potential to become an important part of on-line experimentation as they allow scien-tists to describe and enact their experimental processes in a structured, repeatable andverifiable way.Given the availability of scientist-friendly workflow editors, scientists are moving away from cutting and pasting data between Web pages in favour of producing automated workflows based on Web services. An increasingly large pool of workflows is being shared and made available for re-use. The notion that these workflows and the experimental processes they represent are a useful, re-usable artifact in their own right is new. As a new phenomenon, scientific workflow re-use and discovery is not well understood and it is unclear whether and how it could be supported automatically.The thesis analyses the workflow re-use and discovery process based on surveys, interviews and user experiments with scientists and scientific programmers from different disciplines. We also analyse the impact of using multiple models of computationon workflow re-use. In particular, we show how some models of computation are better re-usable than others.Further, we capture and model scientist re-use and discovery behaviour when re-using data flow workflows from the bioinformatics domain. The result is a suite of human benchmarks of value to developers of workflow discovery techniques.Finally, the benchmarks enable us to evaluate a range of existing service discov-ery based techniques and novel workflow-structure based discovery techniques. Thetechniques vary in the language they work over (natural language or a Semantic Web language) and the level of workflow detail they process. The evaluation shows that performance of the workflow discovery techniques swings substantially depending ont he task in question. This argues in favour of a multi-varied approach that combines multiple techniques
The Design and Realisation of the myExperiment Virtual Research Environment for Social Sharing of Workflows
No full textIn this paper we suggest that the full scientific potential of workflows will be achieved through mechanisms for sharing and collaboration, empowering scientists to spread their experimental protocols and to benefit from those of others. To facilitate this process we have designed and built the myExperiment Virtual Research Environment for collaboration and sharing of workflows and experiments. In contrast to systems which simply make workflows available, myExperiment provides mechanisms to support the sharing of workflows within and across multiple communities. It achieves this by adopting a social web approach which is tailored to the particular needs of the scientist. We present the motivation, design and realisation of myExperiment
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