Interacting services: From specification to execution

Interacting services play a key role to realize business process integration among different business partners by means of electronic message exchange. In order to provide seamless integration of these services, the messages exchanged as well as their dependencies must be well-defined. Service choreographies are a means to describe the allowed conversations. This article presents a requirements framework for service choreography languages, along which existing choreography languages are assessed. The requirements framework provides the basis for introducing the language BPEL4Chor, which extends the industry standard WS-BPEL with choreography-specific concepts. A validation is provided and integration with executable service orchestrations is discussed.     

Web服务环境中的业务过程建模语言比较框架

基于Web服务的价值链集成越来越受到人们的重视,相应的业务过程建模语言成为研究的焦点,各具特色的业务过程建模语言不断出现,对语言的研究、分析和比较已经成为基于Web服务的信息系统集成研究和开发中的一个重要问题。该文在分析Web服务环境下系统集成的体系结构模型基础上,提出了一个Web服务环境下业务过程建模语言比较框架,作为验证,对常见的建模语言进行了比较分析和评述。     

A Compositional Behavioral Modeling Framework for Embedded System Design and Conformance Checking

We propose a framework based on a synchronous multi-clocked model of computation to support the inductive and compositional construction of scalable behavioral models of embedded systems engineered with de facto standard design and programming languages. Behavioral modeling is seen under the paradigm of type inference. The aim of the proposed type system is to capture the behavior of a system under design and to re-factor it by performing global optimizing and architecture-sensitive transformations on it. It allows to modularly express a wide spectrum of static and dynamic behavioral properties and automatically or manually scale the desired degree of abstraction of these properties for efficient verification. The type system is presented using a generic and language-independent static single assignment intermediate representation.     

Semantic model-driven architecting of service-based software systems

Model-driven development is a software development framework that emphasises model-based abstraction and automated code generation. Service-based software architectures benefit in particular from semantic, ontology-based modelling. We present ontology-based transformation and reasoning techniques for layered semantic service architecture modelling. Integrated ontological layers support abstract domain modelling, architectural design, and interoperability aspects. Ontologies are beneficial due to their potential to formally define models, to allow reasoning about semantic models, and to automate transformations at all layers. Ontologies are suitable in particular for the Web Services platform due to their ubiquity within the Semantic Web and their application to support semantic Web services.     

A CAD-CAE integration approach using feature-based multi-resolution and multi-abstraction modelling techniques

In spite of the widespread use of CAD systems for design and CAE systems for analysis, the two processes are not well integrated because CAD and CAE models inherently use different types of geometric models and there currently exists no generic, unified model that allows both design and analysis information to be specified and shared. In this paper, a new approach called the CAD/CAE-integrated approach is proposed and implemented by a feature-based non-manifold modelling system. The system creates and manipulates a single master model containing different types of all of the geometric models required for CAD and CAE. Both a solid model (for CAD) and a non-manifold model (for CAE) are immediately extracted from the master model through a selection process. If a design change is required, the master model is modified by the feature modelling capabilities of the system. As a result, the design and analysis models are modified simultaneously and maintained consistently. This system also supports feature-based multi-resolution and multi-abstraction modelling capabilities providing the CAD model at different levels of detail and the CAE model at various levels of abstraction.     

CONFIDDENT: A model-driven consistent and non-redundant layer-3 firewall ACL design, development and maintenance framework

Design, development, and maintenance of firewall ACLs are very hard and error-prone tasks. Two of the reasons for these difficulties are, on the one hand, the big gap that exists between the access control requirements and the complex and heterogeneous firewall platforms and languages and, on the other hand, the absence of ACL design, development and maintenance environments that integrate inconsistency and redundancy diagnosis. The use of modelling languages surely helps but, although several ones have been proposed, none of them has been widely adopted by industry due to a combination of factors: high complexity, unsupported firewall important features, no integrated model validation stages, etc. In this paper, CONFIDDENT, a model-driven design, development and maintenance framework for layer-3 firewall ACLs is proposed. The framework includes different modelling stages at different abstraction levels. In this way, non-experienced administrators can use more abstract models while experienced ones can refine them to include platform-specific features. CONFIDDENT includes different model diagnosis stages where the administrators can check the inconsistencies and redundancies of their models before the automatic generation of the ACL to one of the many of the market-leader firewall platforms currently supported.     

Mapping the IEC 62264 models onto the Zachman framework for analysing products information traceability: a case study

In order to face new regulation directives regarding the environment and also for improving their customer relationship, enterprises have to increasingly be more able to manage their product information during the entire lifecycle. One of the objectives among others in this paper is to deal with product traceability along the product lifecycle. To meet this objective, the information system has to be designed and, further built in such a way all information regarding products is recorded. The IEC 62264 standards define generic logical models for exchanging product and process information between business and manufacturing levels of enterprise applications. Thus, it can be a base for product information traceability. However, its complexity comes from the fact it mixes conceptual and implementation details while no methodology exists that defines how to instantiate it. Product traceability is then needed to increase its abstraction level in order to concentrate on its concepts and managing its application by providing a methodology for its instantiation. In this paper, we propose to map the IEC 62264 standard models to a particular view of Zachman framework in order to make the framework concrete as a guideline for applying the standard and for providing the key players in information systems design with a methodology to use the standard for traceability purposes.     

A framework for early design and prototyping of service-oriented applications with design patterns

Service-oriented computing is playing an important role in several domains. Today the biggest shift in mainstream design and programming is toward service-oriented applications. However, the service paradigm raises a bundle of problems that did not exist in traditional component-based development where abstraction, encapsulation, and modularity were the only main concerns. Due to their distributed, dynamic, and heterogeneous nature, service-oriented software applications require us to discover, document, and share new design patterns at the service- and architecture-level. Moreover, service-oriented applications are hard to design and validate, and demand for new foundational theories, modeling notations and analysis techniques.In line to such a vision, this article presents a framework, called SCA-PatternBox, to design and prototype service-oriented applications with design patterns. The framework relies on the OASIS standard Service Component Architecture (SCA) and on SCA component implementation types, such as SCA-Java, for supporting an “implementation-oriented” approach to service-oriented architecture modeling and to the definition and instantiation of design patterns. Moreover, in order to provide formally verified design patterns, SCA-PatternBox allows the formal specification and analysis of the functional behavioral aspects of a design pattern using a formal service specification language called SCA-ASM (Service Component Architecture-Abstract State Machine). As major evaluation of the framework, two case studies and lessons learned are presented. A final comparison of existing design pattern languages is also reported.     

MDA环境下可变性元建模方法研究

为模型提供可变性支持对于模型驱动软件开发的实践具有重要意义。可变性建模有利于捕捉领域概念及其特征的共性和差异性,为构造应用模型簇提供了一种模型复用的途径。在研究特征建模的可变性机制和MDA标准建模语言对可变性表示不足的基础上,提出了一种可变性元建模方法,构造可变性概要以支持原子、成组等可变性描述,开发了可变性验证和模型转换算法。通过实际项目的验证,该方法为基于可变性建模的模型内容复用提供了有效支持。     

Design for service compatibility

Service composition is a recent field that has seen a flurry of different approaches proposed towards the goal of flexible distributed heterogeneous interoperation of software systems, usually based on the expectation that such systems must be derived from higher-level models rather than be coded at low level. In practice, achieving service interoperability nonetheless continues to require significant modelling approach at multiple abstraction levels, and existing formal approaches typically require the analysis of the global space of joint executions of interacting services. Based on our earlier work on providing locally checkable consistency rules for guaranteeing the behavioural consistency of inheritance hierarchies, a model-driven approach for creating consistent service orchestrations is proposed. Service execution and interaction is represented with a high-level model in terms of extended Petri net notation; formal criteria are provided for service consistency that can be checked in terms of local model properties, and give a multi-step design approach for developing services that are guaranteed to be interoperable. Finally, it is outlined how the presented results can be carried over and applied to modelling processes using the Business Process Modelling Notation (BPMN).     

Knowledge-aware identity services

The identification problem is concerned with the question whether two objects in an application refer to the same real-world entity. In this paper, the identification problem is investigated from a knowledge modelling point of view. We develop a framework of establishing knowledge-aware identity services by abstracting identity knowledge into an additional identity layer. The knowledge model in the identity service layer provides a capability for combining declarative formulae with concrete data and thus allows us to capture domain-specific identity knowledge at flexible levels of abstraction. By adding validation constraints to the identity service, we are also able to reason about inconsistency of identity knowledge. In doing so, the accuracy of identity knowledge can be improved over time, especially when utilising identity services provided by different communities in a service-oriented architecture. Our experimental study shows the effectiveness of the proposed knowledge modelling approach and the effects of domain-specific identity knowledge on data quality control.     

BIM extension for the sustainability appraisal of conceptual steel design

Contemporary advancements in Information Technology and the efforts from various research initiatives in the AEC industry are showing evidence of progress with the emergence of building information modelling (BIM). BIM presents the opportunity of electronically modelling and managing the vast amount of information embedded in a building project, from its conception to end-of-life. Researchers have been looking at extensions to expand its scope. Sustainability is one such modelling extension that is in need of development. This is becoming pertinent for the structural engineer as recent design criteria have put great emphasis on the sustainability credentials in addition to the traditional criteria of structural integrity, constructability and cost. With the complexity of designs, there are now needs to provide decision support tools to aid in the assessment of the sustainability credentials of design solutions. Such tools would be most beneficial at the conceptual design stage so that sustainability is built into the design solution starting from its inception. The sustainability of buildings is related to life cycle and is measured using indicator-terms such as life cycle costing, ecological footprint and carbon footprint. This paper proposes a modelling framework combining these three indicators in providing sustainability assessments of alternative design solutions based on the economic and environmental sustainability pillars. It employs the principles of feature-based modelling to extract construction-specific information from product models for the purposes of sustainability analysis. A prototype system is implemented using .NET and linked to the BIM enabled software, Revit Structures™. The system appraises alternative design solutions using multi-criteria performance analysis. This work demonstrates that current process and data modelling techniques can be employed to model sustainability related information to inform decisions right from the early stages of structural design. It concludes that the utilized information modelling representations – in the form of a process model, implementation algorithms and object-based instantiations – can capture sustainability related information to inform decisions at the early stages of the structural design process.     

Intelligent support for systems development: The notion and the issues

Enterprise modelling and information systems modelling have traditionally utilized techniques developed in the earlier disciplines of systems analysis and operational analysis. However, these tools have proved insufficient even for information systems modelling and their inadequacies make them less than ideal for enterprise modelling. Furthermore, it has proved difficult to integrate the techniques into a uniform framework representation. Extensive research since the early 1980s has produced support tools for information systems engineering in the academic sector which have generally failed to reach widespread commercial use. Commercially developed integrated support systems aimed at enterprise modelling and information system modelling use traditional techniques, with a lack of formalism. The purpose of this paper is to introduce a technique which overcomes the major inadequacies and which provides an integrating framework to represent both the information and the processing, at enterprise and systems modelling levels of abstraction. The technique is based on the use of a transition network, but extended to represent enterprise and system models in a meaningful way. The use of an intelligent repository, with associated processing of the formally defined requirements, specification and design statements, is novel, and provides the additional support to make the technique amenable to handling the design process from informal to formal specification. The use of a graphical user interface, linked directly to the deductive system and repository, ensures intuitive ease of use.     

A structured marketplace for arbitrary services

Creating simple marketplaces with common rules, that enable the dynamic selection and consumption of functionality, is the missing link to allow small businesses to enter the cloud, not only as consumers, but also as vendors. In this paper, we present the concepts behind a hybrid service and process repository that can act as the foundation for such a marketplace, as well as a prototype that allowed us to test various real-world scenarios. The advantage of a hybrid service and process repository is that, it not only holds a flat list of services, but also exposes a generic set of use cases, that it obtains information on how specific services can be used to implement the use cases as well as information to select services at run-time according to customer’s goal functions.     

The challenge of conceptual modeling for product–service systems: status-quo and perspectives for reference models and modeling languages

Confronted with decreasing margins and a rising customer demand for integrated solutions, manufacturing companies integrate complementary services into their portfolio. Offering value bundles (consisting of services and physical goods) takes place in integrated product–service systems, spanning the coordinated design and delivery of services and physical goods for customers. Conceptual Modeling is an established approach to support and guide such efforts. Using a framework for the design and delivery of value bundles as an analytical lens, this study evaluates the current support of reference models and modeling languages for setting up conceptual models for an integrated design and delivery of value bundles. Consecutively, designing modeling languages and reference models to fit the requirements of conceptual models in product–service systems are presented as upcoming challenges in Service Research. To guide further research, first steps are proposed by exemplarily integrating reference models and modeling languages stemming from the service and manufacturing domains.     

基于Web Service的分布式工作流系统的设计与实现

首先分析了工作流技术的发展和应用现状,指出了其未来的发展趋势;接着介绍了Web Service的一些相关知识,通过了解各种现有的工作流系统,比较各种工作流模型的优缺点,研究并实现了一种基于Web Service的工作流系统,详细阐述了系统框架设计、过程建模设计、工作流引擎设计等的主要原则思想和各主要部件的功能;最后以一个具体项目为例,阐述了基于Web Service的工作流系统的实现过程,通过系统的运行情况看,该工作流系统能大大提高企业的工作效能。     

A flexible,object-centric approach for business process modelling

Mainstream business process modelling techniques often promote a design paradigm wherein the activities that may be performed within a case, together with their usual execution order, form the backbone on top of which other aspects are anchored. This Fordist paradigm, while effective in standardised and production-oriented domains, breaks when confronted with processes in which case-by-case variations and exceptions are the norm. We contend that the effective design of flexible processes calls for a substantially different modelling paradigm. Motivated by requirements from the human services domain, we explore the hypothesis that a framework consisting of a small set of coordination concepts, combined with established object-oriented modelling principles, provides a suitable foundation for designing highly flexible processes. Several human service delivery processes have been designed using this framework, and the resulting models have been used to realise a system to support these processes in a pilot environment.     

Automatic derivation of BPEL4WS from IDEF0 process models

Integration definition for function modelling (IDEF0) is one of the most popular notations for modelling business processes. It employs a rather simple and intuitive modelling construct, consisting of boxes representing functions and arrows connecting them signifying flow of information and materials. Web services on the other hand are an emerging technology for implementing distributed systems. Web service orchestration languages, such as Business Process Execution Language for Web Services (BPEL4WS), are the emerging approach for describing processes as networks of coordinated web services. Business processes as captured in IDEF0 models, however, may contain both web services as well as other types of activities which need to be coordinated. By automatically analysing the Extensible Markup Language (XML) definition of an IDEF0 model, we can identify how web services interact with other activities and at runtime generate code to support the orchestration of web services with the overall business process. The approach proposed is independent of the orchestration language and ensures an implementation independent model for specifying web service orchestrations. This approach also enables the top-down analysis of a business process to its constituent web services and avoids any misalignment problems during design time between the two.