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Guide Me in Analysis: A Framework for Guidance Designers
Guidance is an emerging topic in the field of visual analytics. Guidance can support users in pursuing their analytical goals more efficiently and help in making the analysis successful. However, it is not clear how guidance approaches should be designed and what specific factors should be considered for effective support. In this paper, we approach this problem from the perspective of guidance designers. We present a framework comprising requirements and a set of specific phases designers should go through when designing guidance for visual analytics. We relate this process with a set of quality criteria we aim to support with our framework, that are necessary for obtaining a suitable and effective guidance solution. To demonstrate the practical usability of our methodology, we apply our framework to the design of guidance in three analysis scenarios and a design walk-through session. Moreover, we list the emerging challenges and report how the framework can be used to design guidance solutions that mitigate these issues
Supporting Quality of Service in Scientific Workflows
While workflow management systems have been utilized in enterprises to support
businesses for almost two decades, the use of workflows in scientific environments
was fairly uncommon until recently. Nowadays, scientists use workflow systems to
conduct scientific experiments, simulations, and distributed computations. However,
most scientific workflow management systems have not been built using existing
workflow technology; rather they have been designed and developed from
scratch. Due to the lack of generality of early scientific workflow systems, many
domain-specific workflow systems have been developed. Generally speaking, those
domain-specific approaches lack common acceptance and tool support and offer
lower robustness compared to business workflow systems.
In this thesis, the use of the industry standard BPEL, a workflow language
for modeling business processes, is proposed for the modeling and the execution of
scientific workflows. Due to the widespread use of BPEL in enterprises, a number
of stable and mature software products exist. The language is expressive (Turingcomplete)
and not restricted to specific applications. BPEL is well suited for the
modeling of scientific workflows, but existing implementations of the standard lack
important features that are necessary for the execution of scientific workflows.
This work presents components that extend an existing implementation of the
BPEL standard and eliminate the identified weaknesses. The components thus provide
the technical basis for use of BPEL in academia. The particular focus is on
so-called non-functional (Quality of Service) requirements. These requirements include
scalability, reliability (fault tolerance), data security, and cost (of executing a
workflow). From a technical perspective, the workflow system must be able to interface
with the middleware systems that are commonly used by the scientific workflow
community to allow access to heterogeneous, distributed resources (especially Grid
and Cloud resources).
The major components cover exactly these requirements:
Cloud Resource Provisioner Scalability of the workflow system is achieved by
automatically adding additional (Cloud) resources to the workflow system’s
resource pool when the workflow system is heavily loaded.
Fault Tolerance Module High reliability is achieved via continuous monitoring
of workflow execution and corrective interventions, such as re-execution of a
failed workflow step or replacement of the faulty resource.
Cost Aware Data Flow Aware Scheduler The majority of scientific workflow
systems only take the performance and utilization of resources for the execution
of workflow steps into account when making scheduling decisions. The
presented workflow system goes beyond that. By defining preference values
for the weighting of costs and the anticipated workflow execution time,
workflow users may influence the resource selection process. The developed multiobjective
scheduling algorithm respects the defined weighting and makes both
efficient and advantageous decisions using a heuristic approach.
Security Extensions Because it supports various encryption, signature and authentication
mechanisms (e.g., Grid Security Infrastructure), the workflow
system guarantees data security in the transfer of workflow data.
Furthermore, this work identifies the need to equip workflow developers with
workflow modeling tools that can be used intuitively. This dissertation presents
two modeling tools that support users with different needs. The first tool, DAVO
(domain-adaptable, Visual BPEL Orchestrator), operates at a low level of abstraction
and allows users with knowledge of BPEL to use the full extent of the language.
DAVO is a software that offers extensibility and customizability for different application
domains. These features are used in the implementation of the second tool,
SimpleBPEL Composer. SimpleBPEL is aimed at users with little or no background
in computer science and allows for quick and intuitive development of BPEL workflows based on predefined components
Perspectives on automated composition of workflows in the life sciences [version 1; peer review: 2 approved]
Scientific data analyses often combine several computational tools in automated pipelines, or workflows. Thousands of such workflows have been used in the life sciences, though their composition has remained a cumbersome manual process due to a lack of standards for annotation, assembly, and implementation. Recent technological advances have returned the long-standing vision of automated workflow composition into focus.
This article summarizes a recent Lorentz Center workshop dedicated to automated composition of workflows in the life sciences. We survey previous initiatives to automate the composition process, and discuss the current state of the art and future perspectives. We start by drawing the “big picture” of the scientific workflow development life cycle, before surveying and discussing current methods, technologies and practices for semantic domain modelling, automation in workflow development, and workflow assessment. Finally, we derive a roadmap of individual and community-based actions to work toward the vision of automated workflow development in the forthcoming years.
A central outcome of the workshop is a general description of the workflow life cycle in six stages: 1) scientific question or hypothesis, 2) conceptual workflow, 3) abstract workflow, 4) concrete workflow, 5) production workflow, and 6) scientific results. The transitions between stages are facilitated by diverse tools and methods, usually incorporating domain knowledge in some form. Formal semantic domain modelling is hard and often a bottleneck for the application of semantic technologies. However, life science communities have made considerable progress here in recent years and are continuously improving, renewing interest in the application of semantic technologies for workflow exploration, composition and instantiation. Combined with systematic benchmarking with reference data and large-scale deployment of production-stage workflows, such technologies enable a more systematic process of workflow development than we know today. We believe that this can lead to more robust, reusable, and sustainable workflows in the future.Stian Soiland-Reyes was supported by BioExcel-2 Centre of Excellence, funded by European Commission Horizon
2020 programme under European Commission contract H2020-INFRAEDI-02-2018 823830. Carole Goble was supported by EOSC-Life,
funded by European Commission Horizon 2020 programme under grant agreement H2020-INFRAEOSC-2018-2 824087. We gratefully
acknowledge the financial support from the Lorentz Center, ELIXIR, and the Leiden University Medical Center (LUMC) that made the
workshop possible.
The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscriptPeer Reviewed"Article signat per 33 autors/es: Anna-Lena Lamprecht , Magnus Palmblad, Jon Ison, Veit Schwämmle , Mohammad Sadnan Al Manir, Ilkay Altintas, Christopher J. O. Baker, Ammar Ben Hadj Amor, Salvador Capella-Gutierrez, Paulos Charonyktakis, Michael R. Crusoe, Yolanda Gil, Carole Goble, Timothy J. Griffin , Paul Groth , Hans Ienasescu, Pratik Jagtap, Matúš Kalaš , Vedran Kasalica, Alireza Khanteymoori , Tobias Kuhn12, Hailiang Mei, Hervé Ménager, Steffen Möller, Robin A. Richardson, Vincent Robert9, Stian Soiland-Reyes, Robert Stevens, Szoke Szaniszlo, Suzan Verberne, Aswin Verhoeven, Katherine Wolstencroft "Postprint (published version
-ilities Tradespace and Affordability Project – Phase 3
One of the key elements of the SERC’s research strategy is transforming the practice of systems engineering and associated management practices – “SE and Management Transformation (SEMT).” The Grand Challenge goal for SEMT is to transform the DoD community’s current systems engineering and management methods, processes, and tools (MPTs) and practices away from sequential, single stovepipe system, hardware-first, document-driven, point- solution, acquisition-oriented approaches; and toward concurrent, portfolio and enterprise- oriented, hardware-software-human engineered, model-driven, set-based, full life cycle approaches.This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) under Contract H98230-08- D-0171 (Task Order 0031, RT 046).This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) under Contract H98230-08- D-0171 (Task Order 0031, RT 046)
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