1,913 research outputs found
Petri net approaches for modeling, controlling, and validating flexible manufacturing systems
In this dissertation, we introduce the fundamental ideas and constructs of Petri net models such as ordinary, timed, colored, stochastic, control, and neural, and present some studies that emphasize Petri nets theories and applications as extended research fields that provide suitable platforms in modeling, controlling, validating, and evaluating concurrent systems, information systems, and a versatile dynamic system and manufacturing systems;We then suggest some of extensions that help make Petri nets useful for modeling and analyzing discrete event systems and manufacturing systems models based on the context of a versatile manufacturing system, and applies extended Petri nets models to several manufacturing systems such as an assembly cell, an Automated Palletized Conveyor System, and a tooling machine to show increased modeling power and efficient analysis methods;Finally, Validation methods are presented for these models and results of a performance analysis from a deterministic and stochastic model are used to reorganize and re-evaluate a manufacturing system in order to increase its flexibility
Independent verification of specification models for large software systems at the early phases of development lifecycle
One of the major challenges facing the software industry, in general and IV&V (Independent Verification and Validation) analysts in particular, is to find ways for analyzing dynamic behavior of requirement specifications of large software systems early in the development lifecycle. Such analysis can significantly improve the performance and reliability of the developed systems. This dissertation addresses the problem of developing an IV&V framework for extracting semantics of dynamic behavior from requirement specifications based on: (1) SART (Structured Analysis with Realtime) models, and (2) UML (Unified Modeling Language) models.;For SART, the framework presented here shows a direct mapping from SART specification models to CPN (Colored Petrinets) models. The semantics of the SART hierarchy at the individual levels are preserved in the mapping. This makes it easy for the analyst to perform the analysis and trace back to the corresponding SART model. CPN was selected because it supports rigorous dynamic analysis. A large scale case study based on a component of NASA EOS system was performed for a proof of the concept.;For UML specifications, an approach based on metamodels is presented. A special type of metamodel, called dynamic metamodel (DMM), is introduced. This approach holds several advantages over the direct mapping of UML to CPN. The mapping rules for generating DMM are not CPN specific, hence they would not change if a language other than CPN is used. Also it makes it more flexible to develop DMM because other types of models can be added to the existing UML models. A simple example of a pacemaker is used to illustrate the concepts of DMM
Colored model based testing for software product lines (CMBT-SWPL)
Over the last decade, the software product line domain has emerged as
one of the mostpromising software development paradigms. The main benefits
of a software product lineapproach are improvements in productivity, time
to market, product quality, and customersatisfaction.Therefore, one topic
that needs greater emphasis is testing of software product lines toachieve
the required software quality assurance. Our concern is how to test a
softwareproduct line as early as possible in order to detect errors,
because the cost of error detectedIn early phases is much less compared to
the cost of errors when detected later.The method suggested in this thesis
is a model-based, reuse-oriented test technique calledColored Model Based
Testing for Software Product Lines (CMBT-SWPL). CMBT-SWPLis a
requirements-based approach for efficiently generating tests for products
in a soft-ware product line. This testing approach is used for validation
and verification of productlines. It is a novel approach to test product
lines using a Colored State Chart (CSC), whichconsiders variability early
in the product line development process. More precisely, the vari-ability
will be introduced in the main components of the CSC. Accordingly, the
variabilityis preserved in test cases, as they are generated from colored
test models automatically.During domain engineering, the CSC is derived
from the feature model. By coloring theState Chart, the behavior of
several product line variants can be modeled simultaneouslyin a single
diagram and thus address product line variability early. The CSC
representsthe test model, from which test cases using statistical testing
are derived.During application engineering, these colored test models are
customized for a specificapplication of the product line. At the end of
this test process, the test cases are generatedagain using statistical
testing, executed and the test results are ready for evaluation.
Inxaddition, the CSC will be transformed to a Colored Petri Net (CPN) for
verification andsimulation purposes.The main gains of applying the
CMBT-SWPL method are early detection of defects inrequirements, such as
ambiguities incompleteness and redundancy which is then reflectedin saving
the test effort, time, development and maintenance costs
Second Workshop on Practical Use of Coloured Petri Nets and Design/CPN.
This report contains the proceedings of the Second Workshop on Practical Use of Coloured Petri Nets and Design/CPN, October 13-15, 1999. The workshop was organised by the CPN group at the Department of Computer Science at the University of Aarhus, Denmark. The individual papers are available in electronic form via the web pages: http://www.daimi.au.dk/CPnets/workshop99
Ninth Workshop and Tutorial on Practical Use of Coloured Petri Nets and the CPN Tools, Aarhus, Denmark, October 20-22, 2008
This booklet contains the proceedings of the Ninth Workshop on Practical Use of Coloured Petri Nets and the CPN Tools, October 20-22, 2008. The workshop is organised by the CPN group at the Department of Computer Science, University of Aarhus, Denmark. The papers are also available in electronic form via the web pages: http://www.daimi.au.dk/CPnets/workshop0
Presentation of the 9th Edition of the Model Checking Contest.
International audience; The Model Checking Contest (MCC) is an annual competition of software tools for model checking. Tools must process an increasing benchmark gathered from the whole community and may participate in various examinations: state space generation, computation of global properties, computation of some upper bounds in the model, evaluation of reachability formulas, evaluation of CTL formulas, and evaluation of LTL formulas.For each examination and each model instance, participating tools are provided with up to 3600 s and 16 gigabyte of memory. Then, tool answers are analyzed and confronted to the results produced by other competing tools to detect diverging answers (which are quite rare at this stage of the competition, and lead to penalties).For each examination, golden, silver, and bronze medals are attributed to the three best tools. CPU usage and memory consumption are reported, which is also valuable information for tool developers
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