Component Web Services Research Articles

A Remote Robot Control System Based on RIA and Flex Platform

A remote robot control system was introduced, which is based on RIA (Rich Internet Application) technology and Flex platform. The system is comprised of two parts, which are the robot control module and the design module for foreground Web page application. This paper introduced the functions of each sub block, as well as the design of the programs. Meanwhile, the construction of the whole Web Service system has been specifically outlined. By using Flex technology, the system realized an asynchronous communication between Web and Web Service components， so that the real-time capacity has been greatly enhanced.

CPN-TWS: a coloured petri-net approach for transactional-QoS driven Web Service composition

In this paper, we address the issue of selecting and composing Web Services (WSs) considering functional and Quality of Service (QoS) requirements combined with transactional properties. We formalise the WS functional, QoS and transactional properties as well as the WS Composition problem. We have extended Coloured Petri Net (CPN) formalism to incorporate transactional WSs properties in the composition process. We present and prove our CPN Transactional WS (CPN-TWS) selection algorithm that satisfies the user query functional conditions expressed as input and output attributes, QoS requirements represented by weights over criteria, and transactional properties expressed as a risk level. The result of our algorithm is a CPN corresponding to a Transactional Composite WS whose WS components locally optimise the QoS. We present experimental results to study the performance and the efficiency of our selection algorithm compared with an exhaustive one.

Partitioning composite web services for decentralized execution using a genetic algorithm

Composite web services comprise several component web services. When a composite web service is executed centrally, a single web service engine is responsible for coordinating the execution of the components, which may create a bottleneck and degrade the overall throughput of the composite service when there are a large number of service requests. Potentially this problem can be handled by decentralizing execution of the composite web service, but this raises the issue of how to partition a composite service into groups of component services such that each group can be orchestrated by its own execution engine while ensuring acceptable overall throughput of the composite service. Here we present a novel penalty-based genetic algorithm to solve the composite web service partitioning problem. Empirical results show that our new algorithm outperforms existing heuristic-based solutions.

Modeling and monitoring of construction supply chains

The planning and management of supply chains require properly specifying the participating members and the relationships among them. Construction supply chains usually consist of numerous participants and are complex in structure. Representing construction supply chains using a network model can help understand the complexity, support re-configuration, identify the bottlenecks, and prioritize company’s resources, as well as add values to the management of construction projects. Using a case example on the mechanical, electrical and plumbing (MEP) processes in a construction project, this paper demonstrates the modeling of construction supply chains using the Supply Chain Operations Reference (SCOR) framework developed by the Supply Chain Council (SCC). The SCOR modeling framework provides a structured and systematic way to model and decompose a supply chain from conceptual representation to process element specification. The SCOR framework is commonly used by corporations for strategic planning of their supply chains. This paper further presents a model-based service oriented framework that leverages the SCOR models for performance monitoring of construction supply chains. In the supply chain management and monitoring framework each supply chain process element is implemented as a discrete web service component. The framework is built on a service oriented collaborative system, namely SC Collaborator, that we have developed using web service technology, open standards, and open source technologies.

Geospatial Web Services Semantic Discovery Approach Using Quality

The use of geographic data through Web services shows the geospatial Web Services (GWS). A growing number of GWS designed to interoperate spatial information over the network have emerged. GWS are changing the way in which spatial information systems and applications are designed, developed, and deployed [1]. When GWS is increasing, the difficulty of the service discovery increases too. The service discovery represents one of the interactions between Web service components (supplier, customer and UDDI). It is unfortunately that it is based only on the syntax. The semantic aspect necessary to satisfy the user is absent. The use of semantic Web technology in the Web service discovery phase gives rise to the Web service semantic discovery. The latter is based on semantic reasoning. It enhances the accuracy of search results compared to traditional techniques of Web service discovery, the additional matching accuracy in terms of computing power. In this paper we are interested to the GWS semantic discovery based on geographical metadata held in geo-catalogs. The metadata used in our case is designed according to the ISO 19119 standard reinforced by the quality criteria.

A Grid job monitoring system

This paper presents a web-based Job Monitoring framework for individual Grid sites that allows users to follow in detail their jobs in quasi-real time. The framework consists of several independent components : (a) a set of sensors that run on the site CE and worker nodes and update a database, (b) a simple yet extensible web services framework and (c) an Ajax powered web interface having a look-and-feel and control similar to a desktop application. The monitoring framework supports LSF, Condor and PBS-like batch systems. This is one of the first monitoring systems where an X.509 authenticated web interface can be seamlessly accessed by both end-users and site administrators. While a site administrator has access to all the possible information, a user can only view the jobs for the Virtual Organizations (VO) he/she is a part of. The monitoring framework design supports several possible deployment scenarios. For a site running a supported batch system, the system may be deployed as a whole, or existing site sensors can be adapted and reused with the web services components. A site may even prefer to build the web server independently and choose to use only the Ajax powered web interface. Finally, the system is being used to monitor a glideinWMS instance. This broadens the scope significantly, allowing it to monitor jobs over multiple sites.

A framework to coordinate web services in composition scenarios

This paper looks into the coordination of web services following their acceptance to participate in a composition scenario. We identify two types of behaviours associated with component web services: operational and control behaviours. These behaviours are used to specify composite web services that are built upon component web services. In term of orchestration a composite web service could be either centralised or peer-to-peer. To support component/composite web services coordination per type of orchestration schema, various types of messages are exchanged between these web services. Experiments showing the use of these messages are reported in this paper as well.

The Research on Power SCADA Based on J2EE Framework and IEC 61970

In this paper, the problems exposed by the third generation of SCADA ( S upervisory C ontrol A nd D ata A cquisition) based on the POSIX ( P ortable O perating S ystem I nterface of Unix) standards for UNIX systems are analyzed. Then it makes a brief description of the advantages of the new generation power SCADA system based on the J2EE (Java 2 Platform, Enterprise Edition) framework by using open architecture and object-oriented technologies. The integration bus characterized by standardization and component-based is one the key technologies in implementing this new SCADA system which is based on IEC (International Electrical Commission) 61970. By replacing tightly-coupled CORBA (Common Object Request Broker Architecture) to realize CIS (Component Interface Specification) interfaces, Web services components provide more standard and open interfaces for the information sharing and interoperability among application systems of power enterprises. CIM (Common Information Model) is used to describe power system resources and establish models for the database and SVG (Scalable Vector Graphics) elements. As the graphic expression method of the system, SVG with a combination of CIM achieves integrative graphic model library. The use of advanced design patterns also contributes the scalability to some extent and makes the system much more powerful in dealing with constant changes.

Automatic Generation of Adaptation Contracts

Software development based on the composition of black-box software like Web Services and Software Components is impeded by incompatibilities in their interfaces. Software adaptation has emerged as a solution to these incompatibilities by using processes in-the-middle (called adapters) that allow the correct interaction between the services. There are several approaches that focused on the automated generation of adapters guided by adaptation contracts which specify how the incompatibilities can be resolved. However, the generation of these contracts is not automated and most existing approaches require these contracts to be specified by hand, which obliges the designer to know all the service details. In this paper, we propose an approach to automatically generate adaptation contracts from the behavioral description of the services. These contracts overcome incompatibilities at signature and behavioral levels. Finally we present our prototype tool that accepts as input the service behaviors written in abstract BPEL and generates adaptation contracts using a combination of an A* algorithm and an expert system.

Distributed simulation of DEVS and Cell-DEVS models in CD++ using Web-Services

Discrete event system specification (DEVS) is a modeling and simulation formalism that has been widely used to study the dynamics of discrete event systems. Cell-DEVS is a DEVS-based formalism that defines spatial models as a cell space assembled of a group of DEVS models connected together. CD++ is a modeling and simulation toolkit capable of executing DEVS and Cell-DEVS models that has proven to be useful for executing complex models. We present the design and implementation of a distributed simulation engine, known as D-CD++, which exposes CD++ simulation utilities as machine-consumable services. In addition, we present the design and implementation of the Web-Service components which enable D-CD++ to expose the simulation functionalities to remote users. Enabling CD++ with Web-Services technology provides a solid framework for interoperating different DEVS implementations in order to achieve a standard DEVS Modeling Language and simulation protocols. This paves the road towards DEVS standardization, while providing a mashup approach, which can lead to higher degree of reuse and reduced time to set up and run experiments, and making sharing among remote users more effective. To prove this fact, we integrate it within larger services (such as a 3D visualization engine), showing the mechanism to incorporate to other environments (including geographical information systems, web-based applications and other modeling and simulation tools) through using standard Web-Service tools. Performance of D-CD++, major bottlenecks and communication overheads are analyzed.

INTEROPERABILITY VERIFICATION FOR WEB SERVICE BASED ROBOT COMMUNICATION PLATFORMS AND CONTRIBUTION TO THE INTERNATIONAL STANDARDS

The common robot communication platform using Web Service is well accepted and becoming popular gradually. One of the key components for robot communication platform is the reliable messaging which provides reliable high performance message transfer. Both conforming to standard specifications and interoperability among multiple implementations are critical requirements for the platform, because different robots and different services should be able to connect and communicate each other on the platform. However, there is no conformance/interoperability testing tool for the reliable message component of Web Services. This paper describes requirements for the conformance and interoperability testing for Web Service technologies, and how we developed the verification suit that satisfies the requirements by automated error case verification model. This paper also reports the interoperability verification results for emerging reliable message components of Web Services and our contribution to the international standardization group based on this verification results.

A Web-based ERP system for business services and supply chain management: Application to real-world process scheduling

A Web-based ERP system developed for attacking business problems and managing real-world business processes ranging from simple office automation procedures to complicated supply chain planning is presented. The system’s Web-aspect provides significant advantages, as the system is distributed through interoperable, cross-platform and highly pluggable Web-service components. The system involves a powerful workflow engine that manages the entire process event flow within the enterprise increasing efficiency and control at the same time. Business processes, when needed, are controlled by the enterprise quality management system and consequently the ISO directives are accurately followed. A real-world process scheduling system developed for the specific needs of Greek Construction Manufacturing Enterprises is illustrated as a detailed paradigm of the system’s capabilities. The problem was formulated to assign project tasks in form of lots to enterprise resources in order that resources idle time and delays in project preparation time were minimized. The problem was solved by a simple and effective heuristic algorithm.

Basis path test suite and testing process for WS-BPEL

Web services technology offers a WS-BPEL language for business process execution. The building block of WS-BPEL is those Web services components that collaborate to realize a certain function of th...

A framework for service-oriented computing with C and C++ Web service components

Service-oriented architectures use loosely coupled software services to support the requirements of business processes and software users. Several software engineering challenges have to be overcome to expose legacy C and C++ applications and specialized system resources as XML-based software services. It is critical to devise effective bindings between XML and C/C++ data to efficiently interoperate with other XML-based services. Binding application data to XML has many software solutions, ranging from generic document object models to idiosyncratic type mappings. A safe binding must conform to XML validation constraints, guarantee type safety, and should preserve the structural integrity of communicated application data. However, tight XML bindings impose mapping constraints that can hamper interoperability between services. This paper presents a framework for constructing loosely coupled C/C++ services based on a programming model that integrates XML bindings into the C and C++ syntax. The concepts behind the bindings are generic, which makes the approach applicable to other programming languages.

Automated responsive web service evolution through generative aspect-oriented component adaptation

When building service oriented systems, it is often the case that existing web services do not perfectly match user requirements in target systems. To achieve smooth integration and high reusability of web services, mechanisms to support automated evolution of web services are highly in demand. This paper advocates achieving the above evolution by applying a highly automated aspect-oriented adaptation approach to the underlying components of web services by generating and then applying the adaptation aspects under designed weaving process according to specific adaptation requirements. An expandable library of reusable adaptation aspects at multiple abstraction levels has been developed. A prototype tool is developed to scale up the approach.

Automating the Composition of Transactional Web Services

Composite applications leveraging the functionalities offered by Web services today are the underpinnings of enterprise computing. However, current Web services composition systems make only use of functional requirements in the selection process of component Web services while transactional consistency is a crucial parameter of most business applications. The transactional challenges raised by the composition of Web services are twofold: integrating relaxed atomicity constraints at both design and composition time and coping with the dynamicity introduced by the service oriented computing paradigm. In this paper, we propose a new process to automate the design of transactional composite Web services. Our solution for Web services composition does not take into account functional requirements only but also transactional ones based on the acceptable termination states model. The resulting composite Web service is compliant with the consistency requirements expressed by business application designers and its execution can easily be coordinated using the coordination rules provided as an outcome of our approach. An implementation of our theoretical results augmenting an OWL-S matchmaker is further detailed as a proof of concept.

Development Framework for HL7 Conforming Web Services

Objective: Our purpose is to propose the guideline for developing web services components from HL7 (Health Level 7) standard. Methods: All business processes describing in HL7 are modeled using UML (Unified Modeling Language). Both UML diagrams and web services profiles can be presented with XML (Extensible Markup Language). Therefore we suggest a framework to derive web services from HL7 standards semi-automatically. Results: We show that skeletal XML documents for web services can be generated from HL7 standards. Additionally we propose a way to program with Java for web services using given web service profiles. Conclusion: This paper presents the methodology of developing HL7-compatible electronic health record systems using web services. (Journal of Korean Society of Medical Informatics 13-4, 361-374, 2007)

Toward a Service-Oriented Development Through a Case Study

The rapidly emerging technology of Web services paves a new cost-effective way of engineering software to quickly develop and deploy Web applications by dynamically integrating other independently developed Web-service components to conduct new business transactions. This paper reports our efforts on designing and developing a Web service of pass-through authentication (PTA) for 12 online electronic-payment Web applications. In accordance with how a PTA service is developed and integrated with a corresponding back-end e-payment system, our strategies can be categorized in three stages: end-to-end integration stage, Web-services-enabled stage, and Web-services-oriented stage. Derived from real-world industrial experience, this three-stage pathway can be applied to a broad range of Web-application development projects to guide smooth transformation from a specific application-oriented design and development model toward a reusable Web-services-oriented model. Furthermore, this paper contributes to an engineering process that leads to practical Web-services-oriented software development. New research issues revealed by this project are also reported.

Towards a context-based multi-type policy approach for Web services composition

The objective of this research work is to look into the role of policies and context in framing the composition of Web services. Context supports the development of adaptable Web services and policies specify the behavior of Web services engaged in composition. In this paper, we present this research work’s outcome, namely a context-based multi-type policy for Web services composition in which the binding between Web services occurs at four levels: component level to deal with Web services’ definitions and capabilities, composite level to address how Web services are discovered and combined, semantic level to handle the semantic heterogeneity that can arise between Web services, and resource level to focus on the performance of Web services. Because of the composition complex-nature, the proposed approach uses three types of policies: engagement policies assess a Web service participation in a given composition, mediation policies deal with the semantic heterogeneity by tacking into account the mappings and conversions between component Web services, and deployment policies manage the interactions between component Web services and computing resources. Policies manage the transitions between the four levels and context caters the necessary information that tracks the composition progress.

Standards for image annotation using Semantic Web

The impetus behind Semantic Web research remains the vision of supplementing availability with utility; that is, the World Wide Web provides availability of digital media, but the Semantic Web will allow presently available digital media to be used in unseen ways. An example of such an application is multimedia retrieval. At present, there are vast amounts of digital media available on the web. Once this media gets associated with machine-understandable metadata, the web can serve as a potentially unlimited supplier for multimedia web services, which could populate themselves by searching for keywords and subsequently retrieving images or articles, which is precisely the type of system that is proposed in this paper. Such a system requires solid interoperability, a central ontology, semantic agent search capabilities, and standards. Specifically, this paper explores this cross-section of image annotation and Semantic Web services, models the web service components that constitute such a system, discusses the sequential, cooperative execution of these Semantic Web services, and introduces intelligent storage of image semantics as part of a semantic link space.