The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Peng Hui - One of the best experts on this subject based on the ideXlab platform.
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Workflow Instance migration approach based on virtual execution rules
Journal of Computer Applications, 2006Co-Authors: Peng HuiAbstract:Based on the formal Workflow model and the definition of Workflow Instance with execution history, a comprehensive correctness criterion for Workflow Instance migration was proposed, according to which the virtual execution rule and algorithm were presented. By the comparisons with other similar research works, the advantages of the approach in terms of applicability, correctness and practicality were illustrated.
Rose F. Gamble - One of the best experts on this subject based on the ideXlab platform.
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SERVICES I - Dynamically Changing Workflows of Web Services
2009 Congress on Services - I, 2009Co-Authors: M. Hepner, Robert Baird, Rose F. GambleAbstract:Workflow reconfiguration traditionally modifies only Workflow definitions. Incorporating dynamism in web service Workflows should also adapt Instance execution as services change availability. Commercial Workflow engines lack mechanisms to adapt Instances except where Instances deploy with all possible Workflow paths, to achieve pseudo-dynamism. This error prone method has the potential for unsound specifications and still does not allow runtime modifications. We perform Workflow reconfiguration through an inspection-feedback loop that decouples services specifications and priorities that can change BPEL Workflows from their actual execution. When a change occurs, such as service unavailability, immediate adaptation of the Workflow Instance takes place. To guarantee proper reconfiguration, we formally specify the architecture, interactions, and change directives, according to a natural separation of reconfiguration concerns. We prove the Workflow Instance will correctly adapt to an alternative service when certain conditions are met.
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SERVICES I - Dynamically Changing Workflows of Web Services
2009 Congress on Services - I, 2009Co-Authors: M. Hepner, Robert Baird, Rose F. GambleAbstract:Workflow reconfiguration traditionally modifies only Workflow definitions. Incorporating dynamism in web service Workflows should also adapt Instance execution as services change availability. Commercial Workflow engines lack mechanisms to adapt Instances except where Instances deploy with all possible Workflow paths, to achieve pseudo-dynamism. This error prone method has the potential for unsound specifications and still does not allow runtime modifications. We perform Workflow reconfiguration through an inspection-feedback loop that decouples services specifications and priorities that can change BPEL Workflows from their actual execution. When a change occurs, such as service unavailability, immediate adaptation of the Workflow Instance takes place. To guarantee proper reconfiguration, we formally specify the architecture, interactions, and change directives, according to a natural separation of reconfiguration concerns. We prove the Workflow Instance will correctly adapt to an alternative service when certain conditions are met.
Linh Lam - One of the best experts on this subject based on the ideXlab platform.
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a continuous long running batch orchestration model for Workflow Instance migration
IEEE International Conference on Services Computing, 2010Co-Authors: D J Frank, Liana Fong, Linh LamAbstract:Workflow engines which require process Instances to run to completion against their creation model are limited in their ability to adapt to model changes. The technique of process Instance migration can be used to migrate Instances to a new process model, but at any given time only a fraction of Instances may be in a state which is compatible with the new model. We propose a continuous batch approach for migration which treats migration itself as a long running problem. The continuous migration approach schedules and orchestrates the evaluation and migration of long running processes over time, controlled by configurable policies while maintaining continuous process availability. We have built a long running process migration simulation to test our approach, looking at both migration success and cost. The simulation confirms the need for a long running migration approach and yields some interesting suggestions for tuning the configuration of the migration system.
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IEEE SCC - A Continuous Long Running Batch Orchestration Model for Workflow Instance Migration
2010 IEEE International Conference on Services Computing, 2010Co-Authors: D J Frank, Liana Fong, Linh LamAbstract:Workflow engines which require process Instances to run to completion against their creation model are limited in their ability to adapt to model changes. The technique of process Instance migration can be used to migrate Instances to a new process model, but at any given time only a fraction of Instances may be in a state which is compatible with the new model. We propose a continuous batch approach for migration which treats migration itself as a long running problem. The continuous migration approach schedules and orchestrates the evaluation and migration of long running processes over time, controlled by configurable policies while maintaining continuous process availability. We have built a long running process migration simulation to test our approach, looking at both migration success and cost. The simulation confirms the need for a long running migration approach and yields some interesting suggestions for tuning the configuration of the migration system.
M. Hepner - One of the best experts on this subject based on the ideXlab platform.
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SERVICES I - Dynamically Changing Workflows of Web Services
2009 Congress on Services - I, 2009Co-Authors: M. Hepner, Robert Baird, Rose F. GambleAbstract:Workflow reconfiguration traditionally modifies only Workflow definitions. Incorporating dynamism in web service Workflows should also adapt Instance execution as services change availability. Commercial Workflow engines lack mechanisms to adapt Instances except where Instances deploy with all possible Workflow paths, to achieve pseudo-dynamism. This error prone method has the potential for unsound specifications and still does not allow runtime modifications. We perform Workflow reconfiguration through an inspection-feedback loop that decouples services specifications and priorities that can change BPEL Workflows from their actual execution. When a change occurs, such as service unavailability, immediate adaptation of the Workflow Instance takes place. To guarantee proper reconfiguration, we formally specify the architecture, interactions, and change directives, according to a natural separation of reconfiguration concerns. We prove the Workflow Instance will correctly adapt to an alternative service when certain conditions are met.
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SERVICES I - Dynamically Changing Workflows of Web Services
2009 Congress on Services - I, 2009Co-Authors: M. Hepner, Robert Baird, Rose F. GambleAbstract:Workflow reconfiguration traditionally modifies only Workflow definitions. Incorporating dynamism in web service Workflows should also adapt Instance execution as services change availability. Commercial Workflow engines lack mechanisms to adapt Instances except where Instances deploy with all possible Workflow paths, to achieve pseudo-dynamism. This error prone method has the potential for unsound specifications and still does not allow runtime modifications. We perform Workflow reconfiguration through an inspection-feedback loop that decouples services specifications and priorities that can change BPEL Workflows from their actual execution. When a change occurs, such as service unavailability, immediate adaptation of the Workflow Instance takes place. To guarantee proper reconfiguration, we formally specify the architecture, interactions, and change directives, according to a natural separation of reconfiguration concerns. We prove the Workflow Instance will correctly adapt to an alternative service when certain conditions are met.
Richard Lenz - One of the best experts on this subject based on the ideXlab platform.
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a query language for Workflow Instance data
Advances in Databases and Information Systems, 2014Co-Authors: Philipp Baumgartel, Johannes Tenschert, Richard LenzAbstract:In our simulation project ProHTA (Prospective Health Technology Assessment), we want to estimate the outcome of new medical innovations. To this end, we employ agent-based simulations that require Workflow definitions with associated data about Workflow Instances. For example, to optimize the clinical pathways of patients with stroke we need the time and associated costs of each step in the clinical pathway. We adapt an existing conceptual model to store Workflow definitions and Instance data in RDF. This paper presents a query language to aggregate and query Workflow Instance data. That way, we support domain experts in analyzing simulation input and output. We present a heuristic algorithm for efficient query processing. Finally, we evaluate the performance of our query processing algorithm and compare it to SPARQL.
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ADBIS (2) - A Query Language for Workflow Instance Data
Advances in Intelligent Systems and Computing, 2014Co-Authors: Philipp Baumgartel, Johannes Tenschert, Richard LenzAbstract:In our simulation project ProHTA (Prospective Health Technology Assessment), we want to estimate the outcome of new medical innovations. To this end, we employ agent-based simulations that require Workflow definitions with associated data about Workflow Instances. For example, to optimize the clinical pathways of patients with stroke we need the time and associated costs of each step in the clinical pathway. We adapt an existing conceptual model to store Workflow definitions and Instance data in RDF. This paper presents a query language to aggregate and query Workflow Instance data. That way, we support domain experts in analyzing simulation input and output. We present a heuristic algorithm for efficient query processing. Finally, we evaluate the performance of our query processing algorithm and compare it to SPARQL.
