97,246 research outputs found
Composition and Self-Adaptation of Service-Based Systems with Feature Models
The adoption of mechanisms for reusing software in pervasive systems has not yet become standard practice. This is because the use of pre-existing software requires the selection, composition and adaptation of prefabricated software parts, as well as the management of some complex problems such as guaranteeing high levels of efficiency and safety in critical domains. In addition to the wide variety of services, pervasive systems are composed of many networked heterogeneous devices with embedded software. In this work, we promote the safe reuse of services in service-based systems using two complementary technologies, Service-Oriented Architecture and Software Product Lines. In order to do this, we extend both the service discovery and composition processes defined in the DAMASCo framework, which currently does not deal with the service variability that constitutes pervasive systems. We use feature models to represent the variability and to self-adapt the services during the composition in a safe way taking context changes into consideration. We illustrate our proposal with a case study related to the driving domain of an Intelligent Transportation System, handling the context information of the environment.Work partially supported by the projects TIN2008-05932,
TIN2008-01942, TIN2012-35669, TIN2012-34840 and CSD2007-0004 funded by
Spanish Ministry of Economy and Competitiveness and FEDER; P09-TIC-05231 and
P11-TIC-7659 funded by Andalusian Government; and FP7-317731 funded by EU. Universidad de MĆ”laga. Campus de Excelencia Internacional AndalucĆa Tec
Analysis and design of multiagent systems using MAS-CommonKADS
This article proposes an agent-oriented methodology called MAS-CommonKADS and develops a case study. This methodology extends the knowledge engineering methodology CommonKADSwith techniquesfrom objectoriented and protocol engineering methodologies. The methodology consists of the development of seven models: Agent Model, that describes the characteristics of each agent; Task Model, that describes the tasks that the agents carry out; Expertise Model, that describes the knowledge needed by the agents to achieve their goals; Organisation Model, that describes the structural relationships between agents (software agents and/or human agents); Coordination Model, that describes the dynamic relationships between software agents; Communication Model, that describes the dynamic relationships between human agents and their respective personal assistant software agents; and Design Model, that refines the previous models and determines the most suitable agent architecture for each agent, and the requirements of the agent network
Model-driven design of context-aware applications
In many cases, in order to be effective, software applications need to allow sensitivity to context changes. This implies however additional complexity associated with the need for applicationsā adaptability (being capable of capturing context, interpreting it and reacting on it). Hence, we envision 3 āmustsā that, in combination, are especially relevant to the design of context-aware applications. Firstly, at the business modeling level, it is considered crucial that the different possible context states can be properly captured and modeled, states that correspond to certain desirable behaviors. Secondly, it must be known what are the dependencies between the two, namely between states and behaviors. And finally, what is valid for application design in general, business needs are to be aligned to application solutions. In this work, we address the mentioned challenges, by approaching the notion of context and extending from this perspective a previously proposed business-software alignment approach. We illustrate our achieved results by means of a small example. It is expected that this research contribution will be useful as an additional result concerning the alignment between business modeling and software design
Flexible coordination techniques for dynamic cloud service collaboration
The provision of individual, but also composed services is central in cloud service provisioning. We describe a framework for the coordination of cloud services, based on a tupleāspace architecture which uses an ontology to describe the services. Current techniques for service collaboration offer limited scope for flexibility. They are based on statically describing and compositing services. With the open nature of the web and cloud services, the need for a more flexible, dynamic approach to service coordination becomes evident. In order to support open communities of service providers, there should be the option for these providers to offer and withdraw their services to/from the community. For this to be realised, there needs to be a degree of selfāorganisation. Our techniques for coordination and service matching aim to achieve this through matching goalāoriented service requests with providers that advertise their offerings dynamically. Scalability of the solution is a particular concern that will be evaluated in detail
Ontology-based composition and matching for dynamic cloud service coordination
Recent cross-organisational software service offerings, such as cloud computing, create higher integration needs.
In particular, services are combined through brokers and mediators, solutions to allow individual services to collaborate and their interaction to be coordinated are required. The need to address dynamic management - caused by cloud and on-demand environments - can be addressed through service coordination based on ontology-based composition and matching techniques. Our solution to composition and matching utilises a service coordination space that acts as a passive infrastructure for collaboration where users submit requests that are then selected and taken on by providers. We discuss the information models and the coordination principles of such a collaboration environment in terms of an ontology and its underlying description logics. We provide ontology-based solutions for structural composition of descriptions and matching between requested and provided services
Italian center for Astronomical Archives publishing solution: modular and distributed
The Italian center for Astronomical Archives tries to provide astronomical
data resources as interoperable services based on IVOA standards. Its VO
expertise and knowledge comes from active participation within IVOA and VO at
European and international level, with a double-fold goal: learn from the
collaboration and provide inputs to the community. The first solution to build
an easy to configure and maintain resource publisher conformant to VO standards
proved to be too optimistic. For this reason it has been necessary to re-think
the architecture with a modular system built around the messaging concept,
where each modular component speaks to the other interested parties through a
system of broker-managed queues. The first implemented protocol, the Simple
Cone Search, shows the messaging task architecture connecting the parametric
HTTP interface to the database backend access module, the logging module, and
allows multiple cone search resources to be managed together through a
configuration manager module. Even if relatively young, it already proved the
flexibility required by the overall system when the database backend changed
from MySQL to PostgreSQL+PgSphere. Another implementation test has been made to
leverage task distribution over multiple servers to serve simultaneously: FITS
cubes direct linking, cubes cutout and cubes positional merging. Currently the
implementation of the SIA-2.0 standard protocol is ongoing while for TAP we
will be adapting the TAPlib library. Alongside these tools a first
administration tool (TASMAN) has been developed to ease the build up and
maintenance of TAP_SCHEMA-ta including also ObsCore maintenance capability.
Future work will be devoted at widening the range of VO protocols covered by
the set of available modules, improve the configuration management and develop
specific purpose modules common to all the service components.Comment: SPIE Astronomical Telescopes + Instrumentation 2018, Software and
Cyberinfrastructure for Astronomy V, pre-publishing draft proceeding (reduced
abstract
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Using ERP as a basis for Enterprise application integration
Architecting and implementing e-Business supply chain solutions across and within the modern day enterprise, is now becoming a necessity in order to maintain competitive and be adaptable to market needs. As such, the integration of information and processes is a vital step, using technologies such as using Enterprise Resource Planning (ERP), Supply Chain Management (SCM) and enterprise portal platforms. The effective sharing of resource planning and other enterprise related data across and within the enterprise is typically seen as a facet of a business to business (B2B) platform. However, such infrastructures typically involve a tight integration across intra and inter-organisational systems. This paper examines an Enterprise Application Integration (EAI) initiative taken by a global manufacturer of industrial automation products, which attempted to utilise ERP as an integration tool across its internal B2B infrastructure, to achieve such an aim. This paper discusses those integration considerations and complexities, experienced by the case company upon embarking on an EAI integration programme through the adoption of a core ERP as a catalyst for organizational change. In doing so the authors present an analysis of the inherent risks and limitations of this approach in terms of previously published literature in the field, relating to technology-driven organizational change and EAI impact and adoption frameworks
CloudHealth: A Model-Driven Approach to Watch the Health of Cloud Services
Cloud systems are complex and large systems where services provided by
different operators must coexist and eventually cooperate. In such a complex
environment, controlling the health of both the whole environment and the
individual services is extremely important to timely and effectively react to
misbehaviours, unexpected events, and failures. Although there are solutions to
monitor cloud systems at different granularity levels, how to relate the many
KPIs that can be collected about the health of the system and how health
information can be properly reported to operators are open questions. This
paper reports the early results we achieved in the challenge of monitoring the
health of cloud systems. In particular we present CloudHealth, a model-based
health monitoring approach that can be used by operators to watch specific
quality attributes. The CloudHealth Monitoring Model describes how to
operationalize high level monitoring goals by dividing them into subgoals,
deriving metrics for the subgoals, and using probes to collect the metrics. We
use the CloudHealth Monitoring Model to control the probes that must be
deployed on the target system, the KPIs that are dynamically collected, and the
visualization of the data in dashboards.Comment: 8 pages, 2 figures, 1 tabl
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