Showing papers on "Workflow published in 2005"
TL;DR: The results of improving application performance through workflow restructuring which clusters multiple tasks in a workflow into single entities are presented.
Abstract: This paper describes the Pegasus framework that can be used to map complex scientific workflows onto distributed resources. Pegasus enables users to represent the workflows at an abstract level without needing to worry about the particulars of the target execution systems. The paper describes general issues in mapping applications and the functionality of Pegasus. We present the results of improving application performance through workflow restructuring which clusters multiple tasks in a workflow into single entities. A real-life astronomy application is used as the basis for the study.
1,324 citations
TL;DR: In this paper, a new workflow language (YAWL) is proposed based on a rigorous analysis of existing workflow management systems and workflow languages, and a set of workflow patterns are collected.
1,225 citations
01 Sep 2005
TL;DR: The main aspect of the taxonomy categorizes provenance systems based on why they record provenance, what they describe, how they represent and storeprovenance, and ways to disseminate it.
Abstract: Data management is growing in complexity as large-scale applications take advantage of the loosely coupled resources brought together by grid middleware and by abundant storage capacity. Metadata describing the data products used in and generated by these applications is essential to disambiguate the data and enable reuse. Data provenance, one kind of metadata, pertains to the derivation history of a data product starting from its original sources.In this paper we create a taxonomy of data provenance characteristics and apply it to current research efforts in e-science, focusing primarily on scientific workflow approaches. The main aspect of our taxonomy categorizes provenance systems based on why they record provenance, what they describe, how they represent and store provenance, and ways to disseminate it. The survey culminates with an identification of open research problems in the field.
1,214 citations
20 Jun 2005
TL;DR: The ProM framework is introduced and an overview of the plug-ins that have been developed and is flexible with respect to the input and output format, and is also open enough to allow for the easy reuse of code during the implementation of new process mining ideas.
Abstract: Under the umbrella of buzzwords such as “Business Activity Monitoring” (BAM) and “Business Process Intelligence” (BPI) both academic (e.g., EMiT, Little Thumb, InWoLvE, Process Miner, and MinSoN) and commercial tools (e.g., ARIS PPM, HP BPI, and ILOG JViews) have been developed. The goal of these tools is to extract knowledge from event logs (e.g., transaction logs in an ERP system or audit trails in a WFM system), i.e., to do process mining. Unfortunately, tools use different formats for reading/storing log files and present their results in different ways. This makes it difficult to use different tools on the same data set and to compare the mining results. Furthermore, some of these tools implement concepts that can be very useful in the other tools but it is often difficult to combine tools. As a result, researchers working on new process mining techniques are forced to build a mining infrastructure from scratch or test their techniques in an isolated way, disconnected from any practical applications. To overcome these kind of problems, we have developed the ProM framework, i.e., an “pluggable” environment for process mining. The framework is flexible with respect to the input and output format, and is also open enough to allow for the easy reuse of code during the implementation of new process mining ideas. This paper introduces the ProM framework and gives an overview of the plug-ins that have been developed.
958 citations
Posted Content•
TL;DR: A taxonomy that characterizes and classifies various approaches for building and executing workflows on Grids is proposed that highlights the design and engineering similarities and differences of state-of-the-art in Grid workflow systems, but also identifies the areas that need further research.
Abstract: With the advent of Grid and application technologies, scientists and engineers are building more and more complex applications to manage and process large data sets, and execute scientific experiments on distributed resources. Such application scenarios require means for composing and executing complex workflows. Therefore, many efforts have been made towards the development of workflow management systems for Grid computing. In this paper, we propose a taxonomy that characterizes and classifies various approaches for building and executing workflows on Grids. We also survey several representative Grid workflow systems developed by various projects world-wide to demonstrate the comprehensiveness of the taxonomy. The taxonomy not only highlights the design and engineering similarities and differences of state-of-the-art in Grid workflow systems, but also identifies the areas that need further research.
851 citations
TL;DR: In this article, a taxonomy that characterizes and classifies various approaches for building and executing workflows on Grids has been proposed, highlighting the design and engineering similarities and differences of state-of-the-art in Grid workflow systems, and identifying the areas that need further research.
Abstract: With the advent of Grid and application technologies, scientists and engineers are building more and more complex applications to manage and process large data sets, and execute scientific experiments on distributed resources. Such application scenarios require means for composing and executing complex workflows. Therefore, many efforts have been made towards the development of workflow management systems for Grid computing. In this paper, we propose a taxonomy that characterizes and classifies various approaches for building and executing workflows on Grids. We also survey several representative Grid workflow systems developed by various projects world-wide to demonstrate the comprehensiveness of the taxonomy. The taxonomy not only highlights the design and engineering similarities and differences of state-of-the-art in Grid workflow systems, but also identifies the areas that need further research.
761 citations
01 Sep 2005
TL;DR: A taxonomy that characterizes and classifies various approaches for building and executing workflows on Grids is proposed that highlights the design and engineering similarities and differences of state-of-the-art in Grid workflow systems, but also identifies the areas that need further research.
Abstract: With the advent of Grid and application technologies, scientists and engineers are building more and more complex applications to manage and process large data sets, and execute scientific experiments on distributed resources. Such application scenarios require means for composing and executing complex workflows. Therefore, many efforts have been made towards the development of workflow management systems for Grid computing. In this paper, we propose a taxonomy that characterizes and classifies various approaches for building and executing workflows on Grids. The taxonomy not only highlights the design and engineering similarities and differences of state-of-the-art in Grid workflow systems, but also identifies the areas that need further research.
583 citations
17 Jun 2005
TL;DR: This work describes workflow resource patterns that capture the various ways in which resources are represented and utilised in workflows and uses these patterns as the basis for a detailed comparison of a number of commercially available workflow management systems.
Abstract: In the main, the attention of workflow researchers and workflow developers has focussed on the process perspective, i.e., control-flow. As a result, issues associated with the resource perspective, i.e., the people and machines actually doing the work, have been largely neglected. Although the process perspective is of most significance, appropriate consideration of the resource perspective is essential for successful implementation of workflow technology. Previous work has identified recurring, generic constructs in the control-flow and data perspectives, and presented them in the form of control-flow and data patterns. The next logical step is to describe workflow resource patterns that capture the various ways in which resources are represented and utilised in workflows. These patterns include a number of distinct groupings such as push patterns (“the system pushes work to a worker”) and pull patterns (“the worker pulls work from the system”) to describe the many ways in which work can be distributed. By delineating these patterns in a form that is independent of specific workflow technologies and modelling languages, we are able to provide a comprehensive treatment of the resource perspective and we subsequently use these patterns as the basis for a detailed comparison of a number of commercially available workflow management systems.
505 citations
05 Dec 2005
TL;DR: This paper proposes a cost-based workflow scheduling algorithm that minimizes execution cost while meeting the deadline for delivering results and attempts to optimally solve the task scheduling problem in branches with several sequential tasks by modeling the branch as a Markov decision process and using the value iteration method.
Abstract: Over the last few years, grid technologies have progressed towards a service-oriented paradigm that enables a new way of service provisioning based on utility computing models. Users consume these services based on their QoS (quality of service) requirements. In such "pay-per-use" grids, workflow execution cost must be considered during scheduling based on users' QoS constraints. In this paper, we propose a cost-based workflow scheduling algorithm that minimizes execution cost while meeting the deadline for delivering results. It can also adapt to the delays of service executions by rescheduling unexecuted tasks. We also attempt to optimally solve the task scheduling problem in branches with several sequential tasks by modeling the branch as a Markov decision process and using the value iteration method
469 citations
01 Dec 2005
TL;DR: In this paper, the authors focus on mining social networks using event logs, i.e., a log recording the execution of activities in some business process, e.g., the person initiating or completing some activity.
Abstract: Process mining techniques allow for the discovery of knowledge based on so-called "event logs", i.e., a log recording the execution of activities in some business process. Many information systems provide such logs, e.g., most WFM, ERP, CRM, SCM, and B2B systems record transactions in a systematic way. Process mining techniques typically focus on performance and control-flow issues. However, event logs typically also log the performer, e.g., the person initiating or completing some activity. This paper focuses on mining social networks using this information. For example, it is possible to build a social network based on the hand-over of work from one performer to the next. By combining concepts from workflow management and social network analysis, it is possible to discover and analyze social networks. This paper defines metrics, presents a tool, and applies these to a real event log within the setting of a large Dutch organization.
434 citations
TL;DR: In this article, high-resolution terrestrial lidar acquisition, processing, interpretation, and visualization are discussed and applied to mapping of geological surfaces in 3D dimensions using 3D Digital Outcrop Models (DOMs).
Abstract: Laser ranging is extremely accurate and efficient. Terrestrial scanning lidar (light detection and ranging) applied to outcrop stratigraphic mapping enables researchers to capture laser range data at a rate of thousands of individual X, Y, Z and laser-intensity points per second. These data, in conjunction with complementary remotely and directly sampled data, are used to conduct high-precision facies characterization and to construct 3D geological computer models. Outcrop data are presented here to explain our workflow and to discuss the construction of rock-based 3D Digital Outcrop Models (DOMs). Reproducibility and quantification are the drivers of this methodology. High-resolution terrestrial lidar acquisition, processing, interpretation, and visualization are discussed and applied to mapping of geological surfaces in three dimensions. Laser-generated models offer scientists an unprecedented visualization medium in a quantitative 3D arena. Applications of this technology include constructing and visualizing complex 3D Earth models from outcrops for improved reservoir modeling, flow simulation in hydrocarbon and aquifer systems, and property modeling to constrain forward seismic modeling.
09 May 2005
TL;DR: This work identifies two families of resource allocation algorithms: task-based algorithms that greedily allocate tasks to resources, and workflow- based algorithms that search for an efficient allocation for the entire workflow.
Abstract: Grid applications require allocating a large number of heterogeneous tasks to distributed resources. A good allocation is critical for efficient execution. However, many existing grid toolkits use matchmaking strategies that do not consider overall efficiency for the set of tasks to be run. We identify two families of resource allocation algorithms: task-based algorithms, that greedily allocate tasks to resources, and workflow-based algorithms, that search for an efficient allocation for the entire workflow. We compare the behavior of workflow-based algorithms and task-based algorithms, using simulations of workflows drawn from a real application and with varying ratios of computation cost to data transfer cost. We observe that workflow-based approaches have a potential to work better for data-intensive applications even when estimates about future tasks are inaccurate.
Book•
01 Aug 2005
TL;DR: Essential Business Process Modeling teaches you how to develop examples of process-oriented applications using free tools that can be run on an average PC or laptop and shows how BPM complements enterprise application integration, a method for moving from older applications to new ones, and Enterprise Service BUS for integrating different web services, messaging, and XML technologies into a single network.
Abstract: Ten years ago, groupware bundled with email and calendar applications helped track the flow of work from person to person within an organization. Workflow in today's enterprise means more monitoring and orchestrating massive systems. A new technology called Business Process Management, or BPM, helps software architects and developers design, code, run, administer, and monitor complex network-based business processesSound complicated? It is. But it's downright frustrating when you have to search the Web for every little piece of information vital to the process. Essential Business Process Modeling gathers all the concepts, design, architecture, and standard specifications of BPM into one concise book, and offers hands-on examples that illustrate BPM's approach to process notation, execution, administration and monitoring.Author Mike Havey demonstrates standard ways to code rigorous processes that are centerpieces of a service-oriented architecture (SOA), which defines how networks interact so that one can perform a service for the other. His book also shows how BPM complements enterprise application integration (EAI), a method for moving from older applications to new ones, and Enterprise Service BUS for integrating different web services, messaging, and XML technologies into a single network. BPM, he says, is to this collection of services what a conductor is to musicians in an orchestra: it coordinates their actions in the performance of a larger composition.Essential Business Process Modeling teaches you how to develop examples of process-oriented applications using free tools that can be run on an average PC or laptop. You'll also learn about BPM design patterns and best practices, as well as some underlying theory. The best way to monitor processes within an enterprise is with BPM, and the best way to navigate BPM is with this valuable book. BPM replaces those sketchy flowchart diagrams that business analysts draw on whiteboards with a precise model that uses standard graphical and XML representations, and an architecture that allows it converse with other services, systems, and users.
01 Sep 2005
TL;DR: This paper evaluates three algorithms namely genetic, HEFT, and simple "myopic" and compares incremental workflow partitioning against the full-graph scheduling strategy and demonstrates that full- graph scheduling with the HEFT algorithm performs best.
Abstract: Scheduling is a key concern for the execution of performance-driven Grid applications. In this paper we comparatively examine different existing approaches for scheduling of scientific workflow applications in a Grid environment. We evaluate three algorithms namely genetic, HEFT, and simple "myopic" and compare incremental workflow partitioning against the full-graph scheduling strategy. We demonstrate experiments using real-world scientific applications covering both balanced (symmetric) and unbalanced (asymmetric) workflows. Our results demonstrate that full-graph scheduling with the HEFT algorithm performs best compared to the other strategies examined in this paper.
TL;DR: This paper will present a foundation set of constraints for flexible workflow specification, intended to provide an appropriate balance between flexibility and control, and briefly present Chameleon, a prototype workflow engine that implements these concepts.
11 Jul 2005
TL;DR: This paper proposes an approach to trigger and perform composite service replanning during execution and an evaluation has been performed simulating execution and replanting on a set of composite service workflows.
Abstract: Run-time service discovery and late-binding constitute some of the most challenging issues of service-oriented software engineering. For late-binding to be effective in the case of composite services, a QoS-aware composition mechanism is needed. This means determining the set of services that, once composed, not only will perform the required functionality, but also will best contribute to achieve the level of QoS promised in service level agreements (SLAs). However, QoS-aware composition relies on estimated QoS values and workflow execution paths previously obtained using a monitoring mechanism. At run-time, the actual QoS values may deviate from the estimations, or the execution path may not be the one foreseen. These changes could increase the risk of breaking SLAs and obtaining a poor QoS. Such a risk could be avoided by replanning the service bindings of the workflow slice still to be executed. This paper proposes an approach to trigger and perform composite service replanning during execution. An evaluation has been performed simulating execution and replanning on a set of composite service workflows.
24 Oct 2005
TL;DR: A series of workflow data patterns are described that aim to capture the various ways in which data is represented and utilised in workflows and are used as the basis for a detailed comparison of a number of commercially available workflow management systems, workflow standards and web-service composition languages.
Abstract: Workflow systems seek to provide an implementation vehicle for complex, recurring business processes. Notwithstanding this common objective, there are a variety of distinct features offered by commercial workflow management systems. These differences result in significant variations in the ability of distinct tools to represent and implement the plethora of requirements that may arise in contemporary business processes. Many of these requirements recur quite frequently during the requirements analysis activity for workflow systems and abstractions of these requirements serve as a useful means of identifying the key components of workflow languages. In this paper, we describe a series of workflow data patterns that aim to capture the various ways in which data is represented and utilised in workflows. By delineating these patterns in a form that is independent of specific workflow technologies and modelling languages, we are able to provide a comprehensive treatment of the workflow data perspective and we subsequently use these patterns as the basis for a detailed comparison of a number of commercially available workflow management systems, workflow standards and web-service composition languages.
01 Jul 2005
TL;DR: This paper presents a case study of the development of standards in the area of cross-organizational workflows based on web services, and discusses two opposing types of standards: those based on SOAP, with tightly coupled designs similar to remote procedure calls, and thosebased on REST, with loosely coupled designsSimilar to the navigating of web links.
Abstract: This paper presents a case study of the development of standards in the area of cross-organizational workflows based on web services. We discuss two opposing types of standards: those based on SOAP, with tightly coupled designs similar to remote procedure calls, and those based on REST, with loosely coupled designs similar to the navigating of web links. We illustrate the standardization process, clarify the technical underpinnings of the conflict, and analyze the interests of stakeholders. The decision criteria for each group of stakeholders are discussed. Finally, we present implications for both the workflow and the wider Internet communities.
11 Sep 2005
TL;DR: A business process model can be adopted directly in the multi-agent system, thus reduce the effort on the validation and verification of the interaction protocol (system specification), and provide a lightweight way of re-design of large component based systems.
Abstract: This paper describes the development of a distributed multi-agent workflow enactment mechanism using the BPEL4WS[1] specification. It demonstrates that a multi-agent protocol (Lightweight Coordination Calculus (LCC)[8]) can be used to interpret a BPEL4WS specification to enable distributed business workflow[5] using web services[2] composition on the multi-agent platform. The key difference between our system and other existing multi-agent based web services composition systems is that with our approach, a business process model(system requirement) can be adopted directly in the multi-agent system, thus reduce the effort on the validation and verification of the interaction protocol (system specification). This approach also provides us with a lightweight way of re-design of large component based systems.
05 Apr 2005
TL;DR: This paper delves into the logical optimization of ETL processes, modeling it as a state-space search problem and provides algorithms towards the minimization of the execution cost of an ETL workflow.
Abstract: Extraction-transformation-loading (ETL) tools are pieces of software responsible for the extraction of data from several sources, their cleansing, customization and insertion into a data warehouse. Usually, these processes must be completed in a certain time window; thus, it is necessary to optimize their execution time. In this paper, we delve into the logical optimization of ETL processes, modeling it as a state-space search problem. We consider each ETL workflow as a state and fabricate the state space through a set of correct state transitions. Moreover, we provide algorithms towards the minimization of the execution cost of an ETL workflow.
Patent•
22 Mar 2005TL;DR: In this article, a method for developing and managing workflows is described, which employs computer-implemented forms to control the development, packaging, installation, deployment, enablement, association, instantiation, and termination of workflows.
Abstract: A method for developing and managing workflows is disclosed. The method enables the development of workflows from workflow templates and/or preprogrammed components; associating a workflow with a schedule; modeling a workflow as a plurality of tasks and a plurality of human-to-human or human-to-computer interaction points; and persistently storing the internal state of a workflow. The method employs computer-implemented forms to control the development, packaging, installation, deployment, enablement, association, instantiation, and termination of workflows.
24 Oct 2005
TL;DR: The concepts of workflow and production cycle open up a new horizon for integrating systems and software into what is called a distributed 'Teraflop-workbench' approach.
Abstract: High performance computing has gradually shifted from the realm of research into development and partially even into the production cycles of industry. High performance computers therefore have to be integrated into production environments that demand the simultaneous solution of multidisciplinary physics problems. Supercomputer centers can learn from these new challenges imposed by industry. The concepts of workflow and production cycle open up a new horizon for integrating systems and software into what is called a distributed 'Teraflop-workbench' approach. Terascale storage and communication infrastructures eventually needed to support such an environment.
13 Nov 2005
TL;DR: The ASKALON environment is centered around a set of high-level services for transparent and effective Grid access, including a Scheduler for optimized mapping of workflows onto the Grid, an Enactment Engine for reliable application execution, and a Resource Manager covering both computers and application components.
Abstract: We present the ASKALON environment whose goal is to simplify the development and execution of workflow applications on the Grid. ASKALON is centered around a set of high-level services for transparent and effective Grid access, including a Scheduler for optimized mapping of workflows onto the Grid, an Enactment Engine for reliable application execution, a Resource Manager covering both computers and application components, and a Performance Prediction service based on training phase and statistical methods. A sophisticated XML-based programming interface that shields the user from the Grid middleware details allows the high-level composition of workflow applications. ASKALON is used to develop and port scientific applications as workflows in the Austrian Grid project. We present experimental results using two real-world scientific applications to demonstrate the effectiveness of our approach.
01 Nov 2005
TL;DR: An overview of PADRES is presented, highlighting some of its novel features, including the composite subscription language, the coordination patterns, the composite event detection algorithms, the rule-based router design, and a detailed case study illustrating the decentralized processing of workflows.
Abstract: Distributed publish/subscribe systems are naturally suited for processing events in distributed systems. However, support for expressing patterns about distributed events and algorithms for detecting correlations among these events are still largely unexplored. Inspired from the requirements of decentralized, event-driven workflow processing, we design a subscription language for expressing correlations among distributed events. We illustrate the potential of our approach with a workflow management case study. The language is validated and implemented in PADRES. In this paper we present an overview of PADRES, highlighting some of its novel features, including the composite subscription language, the coordination patterns, the composite event detection algorithms, the rule-based router design, and a detailed case study illustrating the decentralized processing of workflows. Our experimental evaluation shows that rule-based brokers are a viable and powerful alternative to existing, special-purpose, content-based routing algorithms. The experiments also show that the use of composite subscriptions in PADRES significantly reduces the load on the network. Complex workflows can be processed in a decentralized fashion with a gain of 40% in message dissemination cost. All processing is realized entirely in the publish/subscribe paradigm.
TL;DR: The extent with which the BPEL language supports the definition of scientific workflows is explained and the reliability, performance and scalability that can be achieved by executing a complex scientific workflow with ActiveBPEL, an industrial strength but freely available BPEL engine are described.
Abstract: Modern scientific applications often need to be distributed across Grids. Increasingly applications rely on services, such as job submission, data transfer or data portal services. We refer to such services as Grid services. While the invocation of Grid services could be hard coded in theory, scientific users want to orchestrate service invocations more flexibly. In enterprise applications, the orchestration of web services is achieved using emerging orchestration standards, most notably the Business Process Execution Language (BPEL). We describe our experience in orchestrating scientific workflows using BPEL. We have gained this experience during an extensive case study that orchestrates Grid services for the automation of a polymorph prediction application. Using this example, we explain the extent with which the BPEL language supports the definition of scientific workflows. We then describe the reliability, performance and scalability that can be achieved by executing a complex scientific workflow with ActiveBPEL, an industrial strength but freely available BPEL engine.
TL;DR: A critical survey of workflow, workflow description languages, web services and agent technologies is provided and the idea that the Business Process Execution Language for Web Services (BPEL4WS) can be used as a specification language for expressing the initial social order of the multiagent system is advanced.
Abstract: Advances in Information Technology have created opportunities for business enterprises to redesign their information and process management systems. The redesigned systems will likely employ some form of workflow management system. Workflow management systems exactly enact business processes described in a process description language. Unfortunately, such strict adherence to the prescribed workflow makes it impossible for the system to adapt to unforeseen circumstances. We firmly believe that the historic trajectory of software development paradigms and IT advancements will establish multiagent systems as the workflow enactment mechanism of the future. In this paper we provide a critical survey of workflow, workflow description languages, web services and agent technologies. We propose that workflow description languages and their associated design tools can be used to specify a multiagent system. Specifically, we advance the idea that the Business Process Execution Language for Web Services (BPEL4WS) can be used as a specification language for expressing the initial social order of the multiagent system, which can then intelligently adapt to changing environmental conditions.
TL;DR: A new workflow-oriented portal concept that enables the interoperability of various Grids during the execution of workflow applications, and supports users to develop and run their Grid workflows in a collaborative way.
Abstract: Computational Grids connect resources and users in a complex way in order to deliver nontrivial qualities of services. According to the current trend various communities build their own Grids and due to the lack of generally accepted standards these Grids are usually not interoperable. As a result, large scale sharing of resources is prevented by the isolation of Grid systems. Similarly, people are isolated, because the collaborative work of Grid users is not supported by current environments. Each user accesses Grids as an individual person without having the possibility of organizing teams that could overcome the difficulties of application development and execution more easily. The paper describes a new workflow-oriented portal concept that solves both problems. It enables the interoperability of various Grids during the execution of workflow applications, and supports users to develop and run their Grid workflows in a collaborative way. The paper also introduces a classification model that can be used to identify workflow-oriented Grid portals based on two general features: Ability to access multiple Grids, and support for collaborative problem solving. Using the approach the different potential portal types are introduced, their unique features are discussed and the portals and Problem Solving Environments (PSE) of our days are classified. The P-GRADE Portal as a Globus-based implementation for the classification model is also presented.
IBM1
TL;DR: This work presents the first integrated work in composing web services end to end from specification to deployment by synergistically combining the strengths of the above approaches.
Abstract: The demand for quickly delivering new applications is increasingly becoming a business imperative today. Application development is often done in an ad hoc manner, without standard frameworks or libraries, thus resulting in poor reuse of software assets. Web services have received much interest in industry due to their potential in facilitating seamless business-to-business or enterprise application integration. A web services composition tool can help automate the process, from creating business process functionality, to developing executable workflows, to deploying them on an execution environment. However, we find that the main approaches taken thus far to standardize and compose web services are piecemeal and insufficient. The business world has adopted a (distributed) programming approach in which web service instances are described using WSDL, composed into flows with a language like BPEL and invoked with the SOAP protocol. Academia has propounded the AI approach of formally representing web service capabilities in ontologies, and reasoning about their composition using goal-oriented inferencing techniques from planning. We present the first integrated work in composing web services end to end from specification to deployment by synergistically combining the strengths of the above approaches. We describe a prototype service creation environment along with a use-case scenario, and demonstrate how it can significantly speed up the time-to-market for new services.
05 Sep 2005
TL;DR: A collection of workflow patterns formalizations are introduced, each with a sound formal definition and execution semantics, that can be used as a foundation for pattern-based workflow execution, reasoning, and simulation as well as a basis for future research on theoretical aspects of workflow.
Abstract: This paper discusses the application of a general process theory – the π-calculus – for describing the behavioral perspective of workflow. The π-calculus is a process algebra that describes mobile systems. Mobile systems are made up of components that communicate and change their structure as a result of communication. The ideas behind mobility, communication and change can also enrich the workflow domain, where flexibility and reaction to change are main drivers. However, it has not yet been evaluated whether the π-calculus is actually appropriate to represent the behavioral patterns of workflow.
This paper investigates the issue and introduces a collection of workflow patterns formalizations, each with a sound formal definition and execution semantics. The formalizations can be used as a foundation for pattern-based workflow execution, reasoning, and simulation as well as a basis for future research on theoretical aspects of workflow.
Patent•
23 Feb 2005TL;DR: In this paper, a componentized workflow model via an application programming interface is presented, where each step of the workflow is modeled as an activity that has metadata to describe design time aspects, compile time aspects and runtime aspects.
Abstract: Building a componentized workflow model via an application programming interface. Each step of the workflow is modeled as an activity that has metadata to describe design time aspects, compile time aspects, and runtime aspects of the workflow step. A user selects and arranges the activities to create the workflow via the application programming interfaces. The metadata associated with each of the activities in the workflow is collected to create a persistent representation of the workflow. Users extend the workflow model by authoring custom activities. Users also compile the workflow via the application programming interface.