Lightweight query-based analysis of workflow process dependencies

Dependency analysis is important in all of the stages of workflow processes. Workflow elements and features are always difficult to track and as their changes often lead to code tangling as a result of the addition of new requirements and programs. This mosaic quality complicates program comprehension and maintenance. Therefore, an appropriate analysis will help us to identify the potentially affected entities if changes occur. In this paper we present an approach for the lightweight analysis of workflow process dependencies, which include routing, data and roles dependencies. The model is represented as a knowledge base using a logic programming language, Prolog. We develop a set of query rules that can be applied to the well-defined knowledge base at both activity and process levels to retrieve the potentially affected entities. Finally, we use a case study of workflow processes in the healthcare domain to show how our dependency analysis approach works.     

Heterogeneous knowledge representation: integrating connectionist and symbolic computation

Heterogeneous knowledge representation allows combination of several knowledge representation techniques. For instance, connectionist and symbolic systems are two different computational paradigms and knowledge representations. Unfortunately, the integration of different paradigms and knowledge representations is not easy and very often is informal. In this paper, we propose a formal approach to integrate these two paradigms where as a symbolic system we consider a (logic) rule-based system. The integration is operated at language level between neural networks and rule languages. The formal model that allows the integration is based on constraint logic programming and provides an integrated framework to represent and process heterogeneous knowledge. In order to achieve this we define a new language that allows expression and modelling in a natural and intuitive way the above issues together with the operational semantics.     

面向MDA的业务逻辑模型到代码的转换方法研究

业务逻辑自动生成是代码自动生成领域中一个匾待解决的问题。为了解决这个问题,分析了业务逻辑难于生成的原因,在MDA的基础上引入产生式规则的思想,研究PSM模型到代码的转换过程。提出一种基于产生式规则的建模方法对逻辑中业务规则及业务流程进行建横,并基于产生式系统原理,对代码生成器进行设计与实现。基于本方法实现的代码生成器,实现了业务规则及业务流程模型到代码的转换,使目标代码业务逻辑与数据分离,一定程吱上解决了业务逻辑代码自动生成问题。     

Authorized workflow schemas: deciding realizability through \mathsf{LTL }(\mathsf{F }) model checking

Many business processes are modeled as workflows, which often need to comply with business rules, legal requirements, and authorization policies. Workflow satisfiability is the problem of determining whether there exists a workflow instance that realizes the workflow specification while simultaneously complying with such constraints. This problem has already been studied by the computer security community, with the development of algorithms and the study of their worst-case complexity. These solutions are often tailored to a particular workflow model and are, therefore, of little or no use in analyzing different models; their worst-case complexities are likely to be an unreliable judge of their feasibility; and they lack support for other forms of analysis such as the determination of the smallest number of users required to satisfy a workflow specification. We propose model checking of an NP-complete fragment $\mathsf{LTL }(\mathsf{F })$ of propositional linear-time temporal logic as an alternative solution. We report encodings in LTL(F) that can compute a set of solutions (thus deciding satisfiability), compute minimal user bases and a safe bound on the resiliency of satisfiability under the removal of users. These theoretical contributions are validated through detailed experiments whose results attest to the viability of our proposed approach.     

Workflow Requirements Modelling Using XML

When modelling inter-organisational workflow it is important not to make assumptions such as with regard to the formats of the data exchanged between the workflow participants or the technical infrastructures and platforms, as they can restrict the range of possible workflow management implementations. The approach presented in this paper allows for the conceptual modelling of workflow processes using primitive constructs such as nodes, rules and business documents. The paper presents both a graphical notation for modelling workflows as well as a mapping of the workflow constructs to XML models that follows the Workflow Management Coalition interoperability standards. This allows the modelled workflow to be interpreted and executed by a variety of workflow engines.     

Standards-based approaches to B2B workflow integration

E-business automates the overall activities of a company and allows distributed systems to communicate their information. Process automation and information sharing improve a company’s productivity and responsiveness, while Business-to-Business (B2B) workflow systems electronically aid the progress of business processes among trading partners, and also help companies to monitor and administrate their process execution. This study analyzes the technologies and standards for B2B workflow integration, and extracts a reference model for B2B workflow integration. Based on the reference model, three approaches to B2B workflow integration will be introduced here. In addition, we have developed a prototype system of one approach and have illustrated an example for B2B workflow integration. The result of our research can help business partners understand the workflow standards and the messaging technologies for B2B workflow integration, and also help them understand how to implement workflow integration systems that are appropriate to their e-business environments.     

基于SOA的中小制造企业业务流程的集成

分析了传统的企业应用集成中存在的不足以及利用业务流程集成迭代解决这些问题的措施,提出并实现了一种基于面向服务体系架构(SOA)的中小制造企业业务流程集成架构,它支持企业内、外应用以及企业门户的业务流程集成,并充分利用了SOA和XML通信的最新技术.实践证明,该业务流程集成架构具有简单、实用、成本低和易推广等特点.     

可扩展工作流模型的信访业务协同处理系统

根据可定制业务流程和信息安全访问控制的需求,提出了一种可扩展动态工作流的协同处理模型。用户可以按照任务处理环节的需求以工作流子模型为核心定制任务中的活动类型和业务处理逻辑,定制各种附加子模型的业务知识与规则,并将基于角色和任务的访问控制运用于模型中,实现安全访问控制的工作流建模。利用该模型,研发了信访业务协同处理系统,介绍了系统的动态工作流管理技术、基于角色和任务的工作流访问控制与协调处理方法、以及基于任务授权控制的监控机制。三年多的应用情况证明,该系统在系统维护、协同处理、以及监控异常方面,具有应用优势。     

KWM: Knowledge-based Workflow Model for Agile Organization

The workflow management system (WFMS) in an agile organization should be highly adaptable to the frequent organizational changes. To increase the adaptability of contemporary WFMSs, a mechanism for managing changes within the organizational structure and changes in business rules needs to be reinforced. In this paper, a knowledge-based approach for workflow modeling is proposed, in which a workflow is defined as a set of business rules. Knowledge on the organizational structure and special workflow, such as role/actor mappings and complex routing rules, can be explicitly modeled in KWM (Knowledge-based Workflow Model). Using knowledge representation scheme and dependency management facility, a change propagation mechanism is provided to adapt to the frequent changes in the organizational structure, business rules, and procedures.     

Automatic control of workflow processes using ECA rules

Changes in recent business environments have created the necessity for a more efficient and effective business process management. The workflow management system is software that assists in defining business processes as well as automatically controlling the execution of the processes. We propose a new approach to the automatic execution of business processes using event-condition-action (ECA) rules that can be automatically triggered by an active database. First of all, we propose the concept of blocks that can classify process flows into several patterns. A block is a minimal unit that can specify the behaviors represented in a process model. An algorithm is developed to detect blocks from a process definition network and transform it into a hierarchical tree model. The behaviors in each block type are modeled using ACTA formalism. This provides a theoretical basis from which ECA rules are identified. The proposed ECA rule-based approach shows that it is possible to execute the workflow using the active capability of database without users' intervention. The operation of the proposed methods is illustrated through an example process.     

An integrated system for knowledge sharing among heterogeneous knowledge derivation systems

Solving problems in a complex application domain often requires a seamles integration of some existing knowledge derivation systems which have been independently developed for solving subproblems using different inferencing schemes. This paper presents the design and implementation of an Integrated Knowledge Derivation System (IKDS) which allows the user to query against a global database containing data derivable by the rules and constraints of a number of cooperative heterogeneous systems. The global knowledge representation scheme, the global knowledge manipulation language and the global knowledge processing mechanism of IKDS are described in detail. For global knowledge representation, the dynamic aspects of knowledge such as derivational relationships and restrictive dependencies among data items are modeled by a Function Graph to uniformly represent the capabilities (or knowledge) of the rule-based systems, while the usual static aspects such as data items and their structural interrelationships are modeled by an object-oriented model. For knowledge manipulation, three types of high-level, exploratory queries are introduced to allow the user to query the global knowledge base. For deriving the best global answers for queries, the global knowledge processing mechanism allows the rules and constraints in different component systems to be indiscriminately exploited despite the incompatibilities in their inferencing mechanisms and interpretation schemes. Several key algorithms required for the knowledge processing mechanism are described in this paper. The main advantage of this integration approach is that rules and constraints can in effect be shared among heterogeneous rule-based systems so that they can freely exchange their data and operate as parts of a single system. IKDS achieves the integration at the rule level instead of at the system level. It has been implemented in C running in a network of heterogenous component systems which contain three independently developed expert systems with different rule formats and inferencing mechanisms.Database Systems Research and Development Center, Department of Computer Information Sciences, Department of Electrical Engineering, University of Florida     

Ontology-based enterprise knowledge integration

Enterprises are getting more knowledge intensive, and the integration of various types of knowledge becomes a challenge. It has been accepted that ontology is an important concept for knowledge integration. In this paper, three issues have been addressed: (i) ontology construction which includes the method and implementation of a Concept Map based ontology construction, and the evaluation of the constructed ontology; (ii) a dynamic workflow, in which an ontology-based workflow system is used to accumulate knowledge during the business process, and (iii) the rules and constraints used for knowledge representation, in which a Semantic Web Rule Language (SWRL) is used to group the rules and constraints into different classes executed by a inference engine. Two cases have been studied using the above methods and tools. Case one is an acquisition prototype for the aircraft industry. The other is for an on-going bar code management project carried out by this research team. Both cases show that the developed methods can be used for knowledge integration.     

基于工作流的知识流建模与控制

知识在多个参与者之间的产生、传播与应用称为知识流.在知识密集型组织中,对业务过程的控制和对知识资产的管理具有紧密的依赖关系.工作流管理是实现业务过程控制的重要技术.当前的工作流过程元模型不支持对知识管理机制的表示.为此,提出了一个扩展的工作流过程元模型,以支持业务过程控制与知识管理的集成.在此基础上,对知识流的建模与控制进行了深入的研究.提出了一种知识流建模方法,通过5类知识流单元对知识传递与重用、人员协作与交流进行表示.针对知识流中的动态因素,研究了基于资源约束、知识需求变化和时间约束的知识流控制方法,以实现自适应的知识流控制,并给出了有关算法.为工作流技术与知识管理技术的有效结合提供了一个有益的途径.     

基于语义的网格工作流复合技术及实现

作为网格环境的基本服务,网格工作流的大规模共享和重用是使网格成为问题求解的智能化集成环境的一项核心技术。工作流复合技术能够通过已存在的解决方法的重用简化复杂的科学应用问题,而基于语义的工作流复合降低了需要了解工作流语法细节才能重用网格工作流带来的复杂性。首先运用知识表达技术提出一个基于目标概念的网格工作流语义模板,其次介绍了一个实现基于语义的工作流复合的工作流管理原型系统,其中详细阐述了工作流建模过程中基于语义的工作流复合的实现。     

Pattern-based knowledge workflow automation: concepts and issues

As the result of business process automation, more and more knowledge is codified and stored in knowledge repositories and scattered in employees’ computers across functionally and geographically separated business units. While several alternative mechanisms such as chat rooms, search engines, recommender systems exist to retrieve and access knowledge, satisfying a knowledge requirement often involves the coordination of multiple tasks and the use of several technologies. However, there is no existing technology for orchestrating various collaboration, communication and information retrieval components to satisfy the knowledge needs in corporations. In order to address this gap, we propose the approach of pattern-based knowledge workflow that can enable the automation of knowledge flows across an organization. In this paper, we present an overview of the pattern-based knowledge workflow approach and propose extensions to the conventional workflow paradigm. We demonstrate the feasibility of implementing knowledge workflows by means of a Business Process Execution Language (BPEL) specification for executing knowledge workflows in a business setting. We then discuss the engineering challenges and research issues that need to be addressed to further develop this approach.

A practical method to analyze workflow logic models

The analysis of workflow is crucial to the correctness of workflow applications. This paper introduces a simple and practical method for analyzing workflow logic models. Firstly, some definitions of the models and some properties, such as throughness, no‐redundant‐transition and boundedness, are presented. Then, we propose an approach based on synchronized reachability graphs (SRGs) to verify these properties. The SRG uses the characteristics of synchronizers in workflow logic models and mitigates the state explosion by constructing synchronized occurrence sequences rather than interleaving occurrence sequences. This paper also proposes some refined and feasible reduction rules which can preserve vital properties of workflow logic models. Using these two techniques, the SRG‐based verification method can achieve higher efficiency. Furthermore, this research also develops a verification tool based on the method, presents the analysis results of some practical cases and compares our method with others. Copyright © 2007 John Wiley & Sons, Ltd.     

Intelligent system to support judgmental business forecasting: thecase of estimating hotel room demand

Forecasting is an instrumental tool for strategic decision-making in any business activity. Good forecasts can reduce the uncertainty about the future and, hence, help managers make better decisions. Virtually all statistical forecasting techniques depend on the continuity of historical data and time series and may not predict a discontinuous change in the business environment. Often times, this discontinuity is known to managers who then must rely on their judgment to make forecast adjustments. We discuss the role of judgmental forecasting and take the problem of estimating future hotel room demand as a practical business application. Next, we propose IS-JFK: an intelligent system to support judgmental forecasting and knowledge of managers. To account for vagueness in the knowledge elicited from managers and the approximate nature of their reasoning, the system is built around fuzzy IF-THEN rules and uses fuzzy logic for decision inference. IS-JFK supports two methods for forecast adjustments: 1) a direct approach and 2) an approach based on fuzzy intervention analysis. Actual data from a hotel property are used in some case-scenario simulations to illustrate the merits of the intelligent support system     

A semantic approach to a framework for business domain software systems

In enterprise firms, enormous amounts of electronic documents are generated by business analysts and other business domain application users. Applications that use these documents are often driven by business logic that is hard-coded together with application logic. One approach to the separation of business logic from applications is to create and maintain business and information extraction rules in an external, user-friendly format. The drawback of such an externalization is that the business rules, usually, do not have machine interpretable semantics. This situation often leads to misinterpretation of domain analysis documents, which can inhibit the productivity of computer-assisted analytical work and the effectiveness of business solutions. This paper proposes an ontology and rule-based framework for the development of business domain applications, which includes semantic processing of externalized business rules and to some extent externalization of application logic. The creation of external information extraction rules by the business analyst is a cumbersome and time consuming task. In order to overcome this problem, the framework also includes a rule learning system to semi-automate the generation of information extraction rules from source documents with the help of manual annotations. The main idea behind the work presented in this paper is to re-engineer very large enterprise information systems to adapt to Semantic Web computing techniques. The work presented in this paper is inspired by an industrial project.     

Applying Propositional Logic to Workflow Verification

The increasing complexity of business processes in the era of e-business has heightened the need for workflow verification tools. However, workflow verification remains an open and challenging research area. As an indication, most of commercial workflow management systems do not yet provide workflow designers with formal workflow verification tools. We propose a logic-based verification method that is based on a well-known formalism, i.e., propositional logic. Our logic-based workflow verification approach has distinct advantages such as its rigorous yet simplistic logical formalism and its ability to handle generic activity-based process models. In this paper, we present the theoretical framework for applying propositional logic to workflow verification and demonstrate that logic-based workflow verification is capable of detecting process anomalies in workflow models.     

Modeling and Managing Interactions among Business Processes

Most workflow management systems (WfMSs) only support the separate andindependent execution of business processes. However, processes often needto interact with each other, in order to synchronize the execution of theiractivities, to exchange process data, to request execution of services, orto notify progresses in process execution. Recent market trends also raisethe need for cooperation and interaction between processes executed in differentorganizations, posing additional challenges. In fact, in order to reduce costsand provide better services, companies are pushed to increase cooperation and toform virtual enterprises, where business processes span across organizationalboundaries and are composed of cooperating workflows executed in differentorganizations. Workflow interaction in a cross-organizational environment iscomplicated by the heterogeneity of workflow management platforms on top ofwhich workflows are defined and executed and by the different and possiblycompeting business policies and business goals that drive process executionin each organization.In this paper we propose a model and system that enable interactionbetween workflows executed in the same or in different organizations. Weextend traditional workflow models by allowing workflows to publish andsubscribe to events, and by enabling the definition of points in the processexecution where events should be sent or received. Event notifications aremanaged by a suitable event service that is capable of filtering andcorrelating events, and of dispatching them to the appropriate targetworkflow instances. The extended model can be easily mapped onto anyworkflow model, since event specific constructs can be specified by means ofordinary workflow activities, for which we provide the implementation. Inaddition, the event service is easily portable to different platforms, anddoes not require integration with the WfMS that supports the cooperatingworkflows. Therefore, the proposed approach is applicable in virtually anyenvironment and is independent on the specific platform adopted