53,029 research outputs found
Distributed Enforcement of Service Choreographies
Modern service-oriented systems are often built by reusing, and composing
together, existing services distributed over the Internet. Service choreography
is a possible form of service composition whose goal is to specify the
interactions among participant services from a global perspective. In this
paper, we formalize a method for the distributed and automated enforcement of
service choreographies, and prove its correctness with respect to the
realization of the specified choreography. The formalized method is implemented
as part of a model-based tool chain released to support the development of
choreography-based systems within the EU CHOReOS project. We illustrate our
method at work on a distributed social proximity network scenario.Comment: In Proceedings FOCLASA 2014, arXiv:1502.0315
Distributed, cooperating knowledge-based systems
Some current research in the development and application of distributed, cooperating knowledge-based systems technology is addressed. The focus of the current research is the spacecraft ground operations environment. The underlying hypothesis is that, because of the increasing size, complexity, and cost of planned systems, conventional procedural approaches to the architecture of automated systems will give way to a more comprehensive knowledge-based approach. A hallmark of these future systems will be the integration of multiple knowledge-based agents which understand the operational goals of the system and cooperate with each other and the humans in the loop to attain the goals. The current work includes the development of a reference model for knowledge-base management, the development of a formal model of cooperating knowledge-based agents, the use of testbed for prototyping and evaluating various knowledge-based concepts, and beginning work on the establishment of an object-oriented model of an intelligent end-to-end (spacecraft to user) system. An introductory discussion of these activities is presented, the major concepts and principles being investigated are highlighted, and their potential use in other application domains is indicated
Design and implementation of the land surface model NaturalEnvironment within the generic framework OpenDanubia for integrative, distributed environmental modelling
The project GLOWA-Danube (http://www.glowa-danube.de) aimed at
investigating the manifold consequences of Global Change on regional water
resources in the Upper Danube Basin. In order to achieve this task, an
interdisciplinary, university-based network of experts developed the integrative
Decision Support System OpenDanubia (OD). The common base for implementing
and coupling the various scientific model components is a generic framework,
which provides the coordination of the coupled models that run in parallel
exchanging iteratively data via their interfaces. The OD framework takes care of
technical aspects, such as ordered data exchange between sub-models, data
aggregation, data output, model parallelization and data distribution over the
network, which means that model developers do not have to be concerned about
complexities evolving from coupling their models.
Within this framework the sub-model NaturalEnvironment, representing a land
surface model, was developed and implemented. The object-oriented design of this
sub-model facilitates a plain, logical representation of the actual physical processes
simulated by the sub-model. Physical processes to be modelled are organized in
naturally ordered, exchangeable lists that are executed on each spatial
computation unit for each modelling time step, depending on their land cover. The
type of land cover to be simulated on each freely defined spatial unit is
distinguished by one of the three types aquatic, terrestrial and glacier. Additionally,
the type terrestrial is influenced by dynamic land use changes which can be
triggered e.g. by the socio-economic OD sub-model Farming.
This paper presents the basic design of the open source (GPL'ed) OD framework
and highlights the implementation of the sub-model NaturalEnvironment within this
framework, as well as its interactions with other components included in OD
Product to process lifecycle management in assembly automation systems
Presently, the automotive industry is facing enormous pressure due to global competition and ever
changing legislative, economic and customer demands. Product and process development in the
automotive manufacturing industry is a challenging task for many reasons. Current product life
cycle management (PLM) systems tend to be product-focussed. Though, information about
processes and resources are there but mostly linked to the product. Process is an important aspect,
especially in assembly automation systems that link products to their manufacturing resources. This
paper presents a process-centric approach to improve PLM systems in large-scale manufacturing
companies, especially in the powertrain sector of the automotive industry. The idea is to integrate
the information related to key engineering chains i.e. products, processes and resources based upon
PLM philosophy and shift the trend of product-focussed lifecycle management to process-focussed
lifecycle management, the outcome of which is the Product, Process and Resource Lifecycle
Management not PLM only
Managing Uncertainty: A Case for Probabilistic Grid Scheduling
The Grid technology is evolving into a global, service-orientated
architecture, a universal platform for delivering future high demand
computational services. Strong adoption of the Grid and the utility computing
concept is leading to an increasing number of Grid installations running a wide
range of applications of different size and complexity. In this paper we
address the problem of elivering deadline/economy based scheduling in a
heterogeneous application environment using statistical properties of job
historical executions and its associated meta-data. This approach is motivated
by a study of six-month computational load generated by Grid applications in a
multi-purpose Grid cluster serving a community of twenty e-Science projects.
The observed job statistics, resource utilisation and user behaviour is
discussed in the context of management approaches and models most suitable for
supporting a probabilistic and autonomous scheduling architecture
Benchmarks for Parity Games (extended version)
We propose a benchmark suite for parity games that includes all benchmarks
that have been used in the literature, and make it available online. We give an
overview of the parity games, including a description of how they have been
generated. We also describe structural properties of parity games, and using
these properties we show that our benchmarks are representative. With this work
we provide a starting point for further experimentation with parity games.Comment: The corresponding tool and benchmarks are available from
https://github.com/jkeiren/paritygame-generator. This is an extended version
of the paper that has been accepted for FSEN 201
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