Services computing as the foundation of enterprise agility: Overview of recent advances and introduction to the special issue

The advancement of web services in the last few years has spurred a number of revolutionary concepts in information technology and management including service-oriented architectures, service-oriented computing, and services science, management and engineering, which can be collectively called as “services computing.” Services computing is a new research field that goes beyond traditional computing disciplines as it includes not only architectural, programming, deployment, and other engineering issues, but also management issues such as business component modeling, business process design, and service delivery. In this paper, we provide an overview of emerging research concepts in services computing without attempting to unify them as it will take sometime for the field to become mature. In addition, we take a position that the ultimate goal of services computing is to create the necessary technological and managerial foundation to support enterprise agility. In this short paper, we give an overview of services computing, describe its relationship to enterprise agility, and discuss basic technical and managerial issues. Finally, we introduce the papers that are published in this special issue.

Quality-driven optimization of system architecture: Industrial case study on an automotive sub-system

Due to the complexity of today's embedded systems and time-to-market competition between companies developing embedded systems, system architects have to perform a complex task. To design a system which meets all its quality requirements becomes increasingly difficult because of customer demand for new innovative user functions. Methods and tools are needed to assist the architect during system design.     

Reverse engineering relational databases to identify and specify basic Web services with respect to service oriented computing

Service-oriented computing (SOC) is the computing paradigm that utilizes services as a fundamental building block. Services are self-describing, open components intended to support composition of distributed applications. Currently, Web services provide a standard-based realization of SOC due to: (1) the machine-readable format (XML) of their functional and nonfunctional specifications, and (2) their messaging protocols built on top of the Internet. However, how to methodologically identify, specify, design, deploy and manage a sound and complete set of Web services to move to a service-oriented architecture (SOA) is still an issue. This paper describes a process for reverse engineering relational database applications architecture into SOA architecture, where SQL statements are insulated from the applications, factored, implemented, and registered as Web services to be discovered, selected, and reused in composing e-business solutions. The process is based on two types of design patterns: schema transformation pattern and CRUD operations pattern. First, the schema transformation pattern allows an identification of the services. Then the CRUD operations pattern allows a specification of the abstract part of the identified services, namely their port types. This process is implemented as a CASE tool, which assists analysts specifying services that implement common, reusable, basic business logic and data manipulation.

An architectural approach with separation of concerns to address extra-functional requirements in the development of embedded real-time software systems

A large proportion of the requirements on embedded real-time systems stems from the extra-functional dimensions of time and space determinism, dependability, safety and security, and it is addressed at the software level. The adoption of a sound software architecture provides crucial aid in conveniently apportioning the relevant development concerns. This paper takes a software-centered interpretation of the ISO 42010 notion of architecture, enhancing it with a component model that attributes separate concerns to distinct design views. The component boundary becomes the border between functional and extra-functional concerns. The latter are treated as decorations placed on the outside of components, satisfied by implementation artifacts separate from and composable with the implementation of the component internals. The approach was evaluated by industrial users from several domains, with remarkably positive results.     

Challenges and opportunities in collaborative business process management: Overview of recent advances and introduction to the special issue

Modern business process management expands to cover the partner organisations’ business processes across organisational boundaries, and thereby supports organisations to coordinate the flow of information among organisations and link their business processes. With collaborative business processes, organisations can create dynamic and flexible collaborations to synergically adapt to the changing conditions, and stay competitive in the global market. Due to its significant potential and value, collaborative business processes are now turning to be an important issue of contemporary business process management, and attracts lots of attention and efforts from both academic and industry sides. In this paper, we review the development of B2B collaboration and collaborative business processes, provide an overview of related issues in managing collaborative business processes, and discuss some emerging technologies and their relationships to collaborative business processes. Finally, we introduce the papers that are published in this special issue.

CLPL: Providing software infrastructure for the systematic and effective construction of complex collaborative learning systems

Over the last decade, e-Learning and in particular Computer-Supported Collaborative Learning (CSCL) needs have been evolving accordingly with more and more demanding pedagogical and technological requirements. As a result, high customization and flexibility are a must in this context, meaning that collaborative learning practices need to be continuously adapted, adjusted, and personalized to each specific target learning group. These very demanding needs of the CSCL domain represent a great challenge for the research community on software development to satisfy.This contribution presents and evaluates a previous research effort in the form of a generic software infrastructure called Collaborative Learning Purpose Library (CLPL) with the aim of meeting the current and demanding needs found in the CSCL domain. To this end, we experiment with the CLPL in order to offer an advanced reuse-based service-oriented software engineering methodology for developing CSCL applications in an effective and timely fashion. A validation process is provided by reporting on the use of the CLPL platform as the primary resource for the Master's thesis courses at the Open University of Catalonia when developing complex software applications in the CSCL domain.The ultimate aim of the whole research is to yield effective CSCL software systems capable of supporting and enhancing the current on-line collaborative learning practices.     

An architectural approach to the correct and automatic assembly of evolving component-based systems

Software components are specified, designed and implemented with the intention to be reused, and they are assembled in various contexts in order to produce a multitude of software systems. However, in the practice of software development, this ideal scenario is often unrealistic. This is mainly due to the lack of an automatic and efficient support to predict properties of the assembly code by only assuming a limited knowledge of the properties of single components. Moreover, to make effective the component-based vision, the assembly code should evolve when things change, i.e., the properties guaranteed by the assembly, before a change occurs, must hold also after the change. Glue code synthesis approaches technically permit one to construct an assembly of components that guarantees specific properties but, practically, they may suffer from the state-space explosion phenomenon.In this paper, we propose a Software Architecture (SA) based approach in which the usage of the system SA and of SA verification techniques allows the system assembler to design architectural components whose interaction is verified with respect to the specified properties. By exploiting this validation, the system assembler can perform code synthesis by only focusing on each single architectural component, hence refining it as an assembly of actual components which respect the architectural component observable behaviour. In this way code synthesis is performed locally on each architectural component, instead of globally on the whole system interactions, hence reducing the state-space explosion phenomenon.The approach can be equally well applied to efficiently manage the whole reconfiguration of the system when one or more components need to be updated, still maintaining the required properties. The specified and verified system SA is used as starting point for the derivation of glue adaptors that are required to apply changes in the composed system. The approach is firstly illustrated over an explanatory example and is then applied and validated over a real-world industrial case study.     

EXSHOF-II: Active filter design, from approximation function to graphic display of the circuit

This paper presents an expert-system-based package for active filter synthesis, called EXSHOF-II. It starts with approximation function and ends with graphic display of the complete filter circuit. The package is an improved and enhanced version of its mother EXSHOF ( pert system based ynthesis of igh rder ilter). EXSHOF-II gives quantitative and qualitative help at various stages of filter design. Besides the Butterworth, Chebyshev and Elliptic functions which were considered in EXSHOF, the inverse Chebyshev function is also included in EXSHOF-II. For choosing particular approximation EXSHOF-II gives the order of the transfer function. The group delay characteristics of all four approximation functions are plotted on the screen by EXSHOF-II. This aids the user to make a proper choice of an approximation function. Like its mother, EXSHOF-II also considers four high-order structures. The filtering requirement in EXSHOF-II can be directly input on the attenuation characteristics, making the system more user-friendly. The circuit implementation has been done using nine different biquadratic active RC building blocks. The delay requirement can be easily satisfied by cascaded all-pass second-order networks.