71,975 research outputs found
What is the method in applying formal methods to PLC applications?
The question we investigate is how to obtain PLC applications with confidence in their proper functioning. Especially, we are interested in the contribution that formal methods can provide for their development. Our maxim is that the place of a particular formal method in the total picture of system development should be made very clear. Developers and customers ought to understand very well what they can rely on or not, and we see our task in trying to make this explicit. Therefore, for us the answer to the question above leads to the following questions: Which parts of the system can be treated formally? What formal methods and tools can be applied? What does their successful application tell (or does not) about the proper functioning of the whole system
Abstract State Machines 1988-1998: Commented ASM Bibliography
An annotated bibliography of papers which deal with or use Abstract State
Machines (ASMs), as of January 1998.Comment: Also maintained as a BibTeX file at http://www.eecs.umich.edu/gasm
Why Just Boogie? Translating Between Intermediate Verification Languages
The verification systems Boogie and Why3 use their respective intermediate
languages to generate verification conditions from high-level programs. Since
the two systems support different back-end provers (such as Z3 and Alt-Ergo)
and are used to encode different high-level languages (such as C# and Java),
being able to translate between their intermediate languages would provide a
way to reuse one system's features to verify programs meant for the other. This
paper describes a translation of Boogie into WhyML (Why3's intermediate
language) that preserves semantics, verifiability, and program structure to a
large degree. We implemented the translation as a tool and applied it to 194
Boogie-verified programs of various sources and sizes; Why3 verified 83% of the
translated programs with the same outcome as Boogie. These results indicate
that the translation is often effective and practically applicable
Transforming ASN.1 Specifications into CafeOBJ to assist with Property Checking
The adoption of algebraic specification/formal method techniques by the
networks' research community is happening slowly but steadily. We work towards
a software environment that can translate a protocol's specification, from
Abstract Syntax Notation One (ASN.1 - a very popular specification language
with many applications), into the powerful algebraic specification language
CafeOBJ. The resulting code can be used to check, validate and falsify critical
properties of systems, at the pre-coding stage of development. In this paper,
we introduce some key elements of ASN.1 and CafeOBJ and sketch some first steps
towards the implementation of such a tool including a case study.Comment: 8 pages, 12 figure
A Denotational Semantics for Communicating Unstructured Code
An important property of programming language semantics is that they should
be compositional. However, unstructured low-level code contains goto-like
commands making it hard to define a semantics that is compositional. In this
paper, we follow the ideas of Saabas and Uustalu to structure low-level code.
This gives us the possibility to define a compositional denotational semantics
based on least fixed points to allow for the use of inductive verification
methods. We capture the semantics of communication using finite traces similar
to the denotations of CSP. In addition, we examine properties of this semantics
and give an example that demonstrates reasoning about communication and jumps.
With this semantics, we lay the foundations for a proof calculus that captures
both, the semantics of unstructured low-level code and communication.Comment: In Proceedings FESCA 2015, arXiv:1503.0437
Ten virtues of structured graphs
This paper extends the invited talk by the first author about the virtues
of structured graphs. The motivation behind the talk and this paper relies on our
experience on the development of ADR, a formal approach for the design of styleconformant,
reconfigurable software systems. ADR is based on hierarchical graphs
with interfaces and it has been conceived in the attempt of reconciling software architectures
and process calculi by means of graphical methods. We have tried to
write an ADR agnostic paper where we raise some drawbacks of flat, unstructured
graphs for the design and analysis of software systems and we argue that hierarchical,
structured graphs can alleviate such drawbacks
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