@article {Kareliotis2009284,
	title = {IQoS-aware exception resolution for BPEL processes: A middleware-based framework and performance evaluation},
	journal = {International Journal of Web and Grid Services},
	volume = {5},
	number = {3},
	year = {2009},
	note = {cited By (since 1996) 0},
	pages = {284-320},
	abstract = {Web Services Business Process Execution Language (WS-BPEL) is widely used nowadays for specifying and executing composite business processes. During the execution, however, of such business processes, a number of faults stemming from the nature of SOA may occur. The WS-BPEL scenario designer must therefore use the provisions offered by WS-BPEL to catch these exceptions and resolve them. The system fault handler specification, however, is an additional task for the WS scenario designer, while the presence of such handlers within the scenario necessitates extra maintenance activities. In this paper, we propose a middleware-based framework for system exception resolution, which undertakes the tasks of failure interception, discovery of alternative services and their invocation. The process of selecting the alternative services can be driven by process consumer-specified Quality of Service (QoS) policy. Moreover, the middleware arranges for bridging syntactic differences between the originally invoked services and functionally equivalent replacements to it, by employing XSLT-based transformations. The middleware is deployed and maintained independently of the WS-BPEL scenarios, thus removing the need for specifying and maintaining system fault handlers within the scenarios. We also present performance measures, establishing that the overhead imposed by the addition of the proposed middleware layer is minimal. Copyright Β{\textcopyright} 2009, Inderscience Publishers.},
	keywords = {Ad hoc networks, BPEL process, Exception handling, Exception resolution, Middleware, Performance metrics, QoS, Quality control, Quality of service, Scalability, Telecommunication services, Web services},
	doi = {10.1504/IJWGS.2009.028346},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-70349462474\&partnerID=40\&md5=4511b42fde076617cd6ac0139e3f588d},
	author = {Christos Kareliotis and Costas Vassilakis and S. Rouvas and P. Georgiadis}
}
@conference {Christos2009271,
	title = {QoS-driven adaptation of BPEL scenario execution},
	booktitle = {2009 IEEE International Conference on Web Services, ICWS 2009},
	year = {2009},
	note = {cited By (since 1996) 0},
	month = {7},
	pages = {271-278},
	abstract = {BPEL/WSBPEL is the predominant approach for combining individual web services into integrated business processes, allowing for the specification of their sequence, control flow and data exchanges. BPEL however does not include mechanisms for considering the invoked services{\textquoteright} Quality of Service (QoS) parameters and thus BPEL scenarios can neither tailor their execution to the individual user{\textquoteright}s needs or adapt to the highly dynamic environment of the WEB, where new services may be deployed, old ones withdrawn or existing ones changing their QoS parameters. Moreover, infrastructure failures in the distributed environment of the web introduce an additional source of failures that must be considered in the context of QoS-aware service execution. In this work we propose a framework for addressing the issues identified above; the framework allows the users to specify the QoS parameters that they require and it undertakes the task of locating and invoking suitable services. Finally, the proposed framework intercepts and resolves faults occurring during service invocation, respecting the QoS restrictions specified by the consumer. Β{\textcopyright} 2009 IEEE.},
	keywords = {Adaptive execution, BPEL, Control flows, Data exchange, Distributed environments, Dynamic environments, Infrastructure failures, Integrated business, New services, Performance evaliation, QoS parameters, Quality of service, Quality of Service parameters, Service execution, Service invocation, Web services},
	doi = {10.1109/ICWS.2009.80},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-70449472686\&partnerID=40\&md5=5303ebeff04a4e7a062f77209521d561},
	author = {Christos Kareliotis and Costas Vassilakis and S. Rouvas and P. Georgiadis}
}
@conference {Christos2008248,
	title = {Exception resolution for BPEL processes: A middleware-based framework and performance evaluation},
	booktitle = {Proceedings of the 10th International Conference on Information Integration and Web-based Applications and Services, iiWAS 2008},
	year = {2008},
	note = {cited By (since 1996) 0},
	month = {12},
	pages = {248-256},
	abstract = {WS-BPEL is widely used nowadays for specifying and executing composite business processes within the Service Oriented Architecture (SOA). During the execution however, of such business processes, a number of faults stemming from the nature of SOA (e.g. network or server failures) may occur. The WS-BPEL scenario designer must therefore use the provisions offered by WS-BPEL to catch these exceptions and resolve them, usually by invoking some equivalent web service that is expected to be reachable and available. System fault handler specification is though an additional task for the WS scenario designer, while the presence of such handlers within the scenario necessitates extra maintenance activities, as new alternate services emerge or some of the specified ones are withdrawn. In this paper, we propose a middleware-based framework for system exception resolution, which undertakes the tasks of failure interception, discovery of alternate services and their invocation. The middleware is deployed and maintained independently of the WS-BPEL scenarios, removing thus the need for specifying and maintaining system fault handlers within the scenarios. We also present performance measures, establishing that the overhead imposed by the addition of the proposed middleware layer is minimal. Β{\textcopyright} 2008 ACM.},
	keywords = {Ad hoc networks, Business Process, Exception handling, Information retrieval, Information services, Maintenance activity, Middleware, Middleware layer, Performance evaluation, Performance measure, Performance metrics, Quality control, Quality of service, Quality of service (QoS), Scalability, Service oriented architecture (SOA), System faults, Telecommunication services, Web services, WS-BPEL},
	doi = {10.1145/1497308.1497355},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-70349146138\&partnerID=40\&md5=9a5231fe52fffef11707efd4f3489a37},
	author = {Christos Kareliotis and Costas Vassilakis and S. Rouvas and P. Georgiadis}
}
@article {Vassilakis200581,
	title = {Exploiting form semantics and validation checks to improve e-form layout},
	journal = {International Journal of Web Engineering and Technology},
	volume = {2},
	number = {1},
	year = {2005},
	note = {cited By (since 1996) 0},
	pages = {81-96},
	abstract = {On their route to the electronic era, organisations release on the web more and more complex form-based services, which require users to enter numerous data items interrelated by business rules. In such a context, it is crucial to provide optimal form layouts, in order to present the service users with interfaces that facilitate their work. This paper presents an integrated environment, which exploits data item interrelations manifested by the business rules (or validation checks), to optimise the layout of the web forms comprising a complex service. The approach is validated through its application on a tax return form e-service. Copyright Β{\textcopyright} 2005 Inderscience Enterprises Ltd.},
	keywords = {electronic services, Form layout, Form semantics, Integrated environment, Interfaces (computer), Optimization, semantics, Taxation, Usuability, Validation checks, World Wide Web},
	doi = {10.1504/IJWET.2005.007465},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-24344507764\&partnerID=40\&md5=e94b487785303410cb7bf88df9d12c86},
	author = {Costas Vassilakis and Giorgos Lepouras and S. Rouvas and P. Georgiadis}
}
@article {DBLP:journals/eg/VassilakisLRG04,
	title = {Integrating e-government public transactional services into public authority workflows},
	journal = {Electronic Government},
	volume = {1},
	number = {1},
	year = {2004},
	pages = {49-60},
	abstract = {Documents submitted by citizens through electronic services deployed in the context of e-Government must usually undergo processing by some organisational information system, in order to complete the citizens? requests and for the reply to be returned to the citizen. The integration, however, of the e-service delivery platform and the organisational information system is often hindered for a number of reasons, including security considerations, platform diversity or idiosyncrasies of legacy information systems. In this paper we present a generic method for providing seamless communication between the two platforms, enabling the full integration of documents submitted through electronic services into the organisational workflow, leveraging thus the quality of services offered to the citizens and facilitating e-service development and operation.},
	doi = {10.1504/EG.2004.004136},
	author = {Costas Vassilakis and Giorgos Lepouras and S. Rouvas and P. Georgiadis}
}
@article {Vassilakis2003315,
	title = {A framework for managing the lifecycle of transactional e-government services},
	journal = {Telematics and Informatics},
	volume = {20},
	number = {4},
	year = {2003},
	note = {cited By (since 1996) 13},
	pages = {315-329},
	abstract = {Filling and submission of electronic forms is a key issue for e-government, since most electronic services offered in this context include some variant of electronic forms. Insofar, IT experts are placed in the centre of electronic forms services lifecycles, undertaking the analysis, design, implementation and maintenance phases. This practice, however, implies various impediments, such as the need for multitudinous teams with diverse skills. In this paper, we present experiences from developing and maintaining a set of electronic services for the Greek Ministry of Finance, and propose an approach to handling electronic services{\textquoteright} lifecycle that balances responsibilities between domain experts and IT professionals. This approach enables a more holistic management of the electronic service lifecycle, by employing modelling and representation in high levels of abstraction and incorporating tools for automatically generating operative service instances from these high-level descriptions. Β{\textcopyright} 2003 Elsevier Science Ltd. All rights reserved.},
	keywords = {Communication, Electronic forms, Information science, Information technology},
	doi = {10.1016/S0736-5853(03)00011-X},
	url = {https://www.sciencedirect.com/science/article/abs/pii/S073658530300011X},
	author = {Costas Vassilakis and Laskaridis, G. and Giorgos Lepouras and S. Rouvas and P. Georgiadis}
}
@conference {DBLP:conf/caise/VassilakisLRG03,
	title = {Improving e-Form Layout Through Analysis of Form Semantics and Validation Checks},
	booktitle = {CAiSE Short Paper Proceedings},
	year = {2003},
	month = {6},
	abstract = {Transaction services offered by public authorities vary from simple forms with few fields to multi-form compound documents with hundreds of input areas. In the latter case, field placement within forms is of particular importance for facilitating the filling and error correction processes. In this paper we present an approach to improving the form layout by exploiting validation checks that are usually associated with electronic forms, as well as semantic information that may be attached to form fields by designers.},
	url = {http://ceur-ws.org/Vol-74/files/FORUM_38.pdf},
	author = {Costas Vassilakis and Giorgos Lepouras and S. Rouvas and P. Georgiadis}
}
@conference {667640,
	title = {An Object-Oriented Approach for Designing Administrative E-forms and Transactional E-services},
	booktitle = {OOIS {\textquoteright}02: Proceedings of the 8th International Conference on Object-Oriented. Information Systems},
	year = {2002},
	month = {9},
	pages = {19{\textendash}30},
	publisher = {Springer-Verlag},
	organization = {Springer-Verlag},
	address = {London, UK},
	abstract = {Although electronic transaction services are considered to be a necessity for e-government, it has not been possible insofar to unleash their full potential. E-forms are central to the development of e-government, being a basic means for implementing the majority of the public services considered as required for local and central public administration authorities. In this paper, we present an object-oriented model for e-form-based administrative services, which spans the e-service lifecycle, including development, deployment and use by enterprises and citizens, data collection and communication with legacy information systems. The proposed approach encompasses semantic, structural and active aspects of e-forms, providing thus an inclusive framework for modelling electronic services.},
	isbn = {3-540-44087-9},
	doi = {10.1007/3-540-46102-7_6},
	author = {D. Gouscos and S. Rouvas and Costas Vassilakis and P. Georgiadis}
}
@conference {lep2002a1,
	title = {SMARTGOV: A Governmental Knowledge-based Platform for Public Sector Online Services},
	booktitle = {Proceedings KMGov2002},
	year = {2002},
	month = {5},
	pages = {173{\textendash}185},
	address = {Copenhagen, Denmark},
	abstract = {Public transaction services (such as e-forms), although perceived the future of e-government have not yet realised their full potential. E-forms have a significant role in e-government, as they are the basis for realising most of the twenty public services that all European Union member states have to provide to their citizens and businesses. The aim of this paper is to present a knowledge-based platform to assist public sector employees to generate online transaction services by simplifying their development, maintenance and integration with already installed IT systems.},
	author = {E. Tambouris and G. Boukis and Costas Vassilakis and Giorgos Lepouras and S. Rouvas and Canadas, R. and Heredia, S. and Lopez Usero, J. C.}
}
@conference {650426,
	title = {Transactional e-Government Services: An Integrated Approach},
	booktitle = {EGOV {\textquoteright}02: Proceedings of the First International Conference on Electronic Government},
	year = {2002},
	month = {9},
	pages = {276{\textendash}279},
	publisher = {Springer-Verlag},
	organization = {Springer-Verlag},
	address = {London, UK},
	abstract = {Although form-based transactional services are fundamental to electronic government activities, their widespread does neither meet the citizen{\textquoteright}s expectations, nor the potential offered by state-of-the-art technologies. Besides any bureaucratic impediments, the primary reason for this is that traditional software engineering approaches cannot satisfactorily handle all the aspects of electronic services lifecycle. In this paper we present experiences from developing and maintaining a set of electronic services for the Greek Ministry of Finance, and propose a new approach for handling electronic service projects. The proposed approach has been successfully employed for developing extensions to the existing services, as well as some new ones.},
	isbn = {3-540-44121-2},
	doi = {10.1007/978-3-540-46138-8_44},
	url = {http://link.springer.com/chapter/10.1007\%2F978-3-540-46138-8_44},
	author = {Costas Vassilakis and Laskaridis, G. and Giorgos Lepouras and S. Rouvas and P. Georgiadis}
}
@conference {Lask2001a,
	title = {e-Citizens and e-Consumers: Is There a Difference?},
	booktitle = {Proceedings of the PCHCI 2001 Workshop: "Transforming Web Surfers to E-Shoppers"},
	year = {2001},
	month = {12},
	pages = {47-50},
	abstract = {Both the business sector and the government are nowadays embracing Internet technologies in order to provide high quality on-line services to their "target groups". In both cases, service providers are trying to transform web surfers, casually visiting their web sites to seek information, to users of their electronic services, i.e. e-consumers and. e-citizens. In this paper, we address the similarities and the differences between the business and the government, when they act as service providers, with respect to the factors for successful service and the issues that must be addressed.},
	author = {Laskaridis, G. and Costas Vassilakis and Giorgos Lepouras and S. Rouvas}
}
