167 research outputs found
Automating property-based testing of evolving web services
Web services are the most widely used service technology that drives the Service-Oriented Computing~(SOC) paradigm. As a result, effective testing of web services is getting increasingly important. In this paper, we present a framework and toolset for testing web services and for evolving test code in sync with the evolution of web services. Our approach to testing web services is based on the Erlang programming language and QuviQ QuickCheck, a property-based testing tool written in Erlang, and our support for test code evolution is added to Wrangler, the Erlang refactoring tool.
The key components of our system include the automatic generation of initial test code, the inference of web service interface changes between versions, the provision of a number of domain specific refactorings and the automatic generation of refactoring scripts for evolving the test code. Our framework provides users with a powerful and expressive web service testing framework, while minimising users' effort in creating, maintaining and evolving the test model. The framework presented in this paper can be used by both web service providers and consumers, and can be used to test web services written in whatever language; the approach advocated here could also be adopted in other property-based testing frameworks and refactoring tools
IT Services Market Analysis
The IT services market represents an attractive set of markets with potential for profit. As technology matures, firms now see and accept the benefits that these technologies bring to their existing business environments. With the wide possibilities within the IT services field, service providers must now evaluate the market they desire to participate in. I have analyzed aspects such as potential market demand and entry barriers to gain a basic understanding of the competitive outlook for knowledge management, systems integration and web services. I also used concentration ratio data to calibrate and understand the level of competition experienced within these fields. Key findings include an overall low impact from regulatory and capital requirements to enter these markets. Paired with a high level of fragmentation, these IT markets have great potential to benefit from the forecasted growth and establish profitable businesses
A distributed architecture for efficient Web service discovery
open3noAlthough the definition of service-oriented architecture (SOA) included the presence of a service registry from the beginning, the first implementations (e.g., UDDI) did not really succeed mainly because of security and governance issues. This article tackles the problem by introducing DREAM (Distributed Registry by ExAMple): a publish/subscribe-based solution to integrate existing, different registries, along with a match-making approach to ease the publication and retrieval of services. DREAM fosters the interoperability among registry technologies and supports UDDI, ebXML Registry, and other registries. The publish/subscribe paradigm allows service providers to decide the services they want to publish, and requestors to be informed of the services that satisfy their interests. As for the match-making, DREAM supports different ways to evaluate the matching between published and required services. Besides presenting the architecture of DREAM and the different match-making opportunities, the article also describes the experiments conducted to evaluate proposed solutions.Baresi, Luciano; Miraz, Matteo; Plebani, PierluigiBaresi, Luciano; Miraz, Matteo; Plebani, Pierluig
QoS Composition and Analysis in Reconfigurable Web Services Choreographies
International audienceQuality of Service (QoS) in orchestrated web services compositions have been well studied with probabilistic and multi-dimensional models. Choreographies that involve message passing among services, on the other hand, require further analysis. In this paper, we begin with the set of QoS domains that may be studied in case of choreographies and the algebraic rules for their composition. As choreographies manage QoS composition in a distributed fashion, techniques to enrich functional specifications with QoS are examined using the model proposed in the CHOReOS project. These are further analyzed with choreographies that may reconfigure due to functional or QoS requirements. Studies on the effects of such reconfiguration on multiple QoS domains can lead to better understanding of optimal runtime configurations along with associated tradeoffs. A goal programming approach is also proposed to choose Pareto optimal solutions with respect to diverse QoS domains
AI and Jobs: Has the Inflection Point Arrived? Evidence from an Online Labor Platform
Artificial intelligence (AI) refers to the ability of machines or software to
mimic or even surpass human intelligence in a given cognitive task. While
humans learn by both induction and deduction, the success of current AI is
rooted in induction, relying on its ability to detect statistical regularities
in task input -- an ability learnt from a vast amount of training data using
enormous computation resources. We examine the performance of such a
statistical AI in a human task through the lens of four factors, including task
learnability, statistical resource, computation resource, and learning
techniques, and then propose a three-phase visual framework to understand the
evolving relation between AI and jobs. Based on this conceptual framework, we
develop a simple economic model of competition to show the existence of an
inflection point for each occupation. Before AI performance crosses the
inflection point, human workers always benefit from an improvement in AI
performance, but after the inflection point, human workers become worse off
whenever such an improvement occurs. To offer empirical evidence, we first
argue that AI performance has passed the inflection point for the occupation of
translation but not for the occupation of web development. We then study how
the launch of ChatGPT, which led to significant improvement of AI performance
on many tasks, has affected workers in these two occupations on a large online
labor platform. Consistent with the inflection point conjecture, we find that
translators are negatively affected by the shock both in terms of the number of
accepted jobs and the earnings from those jobs, while web developers are
positively affected by the very same shock. Given the potentially large
disruption of AI on employment, more studies on more occupations using data
from different platforms are urgently needed.Comment: 42 pages, 6 figures, 9 table
Non-Local Configuration of Component Interfaces by Constraint Satisfaction
© 2020 Springer-Verlag. The final publication is available at Springer via https://doi.org/10.1007/s10601-020-09309-y.Service-oriented computing is the paradigm that utilises services as fundamental elements for developing applications. Service composition, where data consistency becomes especially important, is still a key challenge for service-oriented computing. We maintain that there is one aspect of Web service communication on the data conformance side that has so far escaped the researchers attention. Aggregation of networked services gives rise to long pipelines, or quasi-pipeline structures, where there is a profitable form of inheritance called flow inheritance. In its presence, interface reconciliation ceases to be a local procedure, and hence it requires distributed constraint satisfaction of a special kind. We propose a constraint language for this, and present a solver which implements it. In addition, our approach provides a binding between the language and C++, whereby the assignment to the variables found by the solver is automatically translated into a transformation of C++ code. This makes the C++ Web service context compliant without any further communication. Besides, it uniquely permits a very high degree of flexibility of a C++ coded Web service without making public any part of its source code.Peer reviewe
Reviewing the interface of bioeconomy and ecosystem service research
The bioeconomy is currently being globally promoted as a sustainability avenue involving several societal actors. While the bioeconomy is broadly about the substitution of fossil resources with bio-based ones, three main (competing or complementary) bioeconomy visions are emerging in scientific literature: resource, biotechnology, and agroecology. The implementation of one or more of these visions into strategies implies changes to land use and thus ecosystem services delivery, with notable trade-offs. This review aims to explore the interdisciplinary space at the interface of these two concepts. We reviewed scientific publications explicitly referring to bioeconomy and ecosystem services in their title, abstract, or keywords, with 45 documents identified as relevant. The literature appeared to be emerging and fragmented but eight themes were discernible (in order of decreasing occurrence frequency in the literature): a. technical and economic feasibility of biomass extraction and use; b. potential and challenges of the bioeconomy; c. frameworks and tools; d. sustainability of bio-based processes, products, and services; e. environmental sustainability of the bioeconomy; f. governance of the bioeconomy; g. biosecurity; h. bioremediation. Approximately half of the documents aligned to a resource vision of the bioeconomy, with emphasis on biomass production. Agroecology and biotechnology visions were less frequently found, but multiple visions generally tended to occur in each document. The discussion highlights gaps in the current research on the topic and argues for communication between the ecosystem services and bioeconomy communities to forward both research areas in the context of sustainability science.Peer reviewe
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