554,038 research outputs found
Characterizing Behavioural Congruences for Petri Nets
We exploit a notion of interface for Petri nets in order to design a set of net combinators. For such a calculus of nets, we focus on the behavioural congruences arising from four simple notions of behaviour, viz., traces, maximal traces, step, and maximal step traces, and from the corresponding four notions of bisimulation, viz., weak and weak step bisimulation and their maximal versions. We characterize such congruences via universal contexts and via games, providing in such a way an understanding of their discerning powers
Termination Analysis by Learning Terminating Programs
We present a novel approach to termination analysis. In a first step, the
analysis uses a program as a black-box which exhibits only a finite set of
sample traces. Each sample trace is infinite but can be represented by a finite
lasso. The analysis can "learn" a program from a termination proof for the
lasso, a program that is terminating by construction. In a second step, the
analysis checks that the set of sample traces is representative in a sense that
we can make formal. An experimental evaluation indicates that the approach is a
potentially useful addition to the portfolio of existing approaches to
termination analysis
Algebraic Structure of Combined Traces
Traces and their extension called combined traces (comtraces) are two formal
models used in the analysis and verification of concurrent systems. Both models
are based on concepts originating in the theory of formal languages, and they
are able to capture the notions of causality and simultaneity of atomic actions
which take place during the process of a system's operation. The aim of this
paper is a transfer to the domain of comtraces and developing of some
fundamental notions, which proved to be successful in the theory of traces. In
particular, we introduce and then apply the notion of indivisible steps, the
lexicographical canonical form of comtraces, as well as the representation of a
comtrace utilising its linear projections to binary action subalphabets. We
also provide two algorithms related to the new notions. Using them, one can
solve, in an efficient way, the problem of step sequence equivalence in the
context of comtraces. One may view our results as a first step towards the
development of infinite combined traces, as well as recognisable languages of
combined traces.Comment: Short variant of this paper, with no proofs, appeared in Proceedings
of CONCUR 2012 conferenc
Classifying Invariant Structures of Step Traces
In the study of behaviours of concurrent systems, traces are sets of behaviourally equivalent action sequences. Traces can be represented by causal partial orders. Step traces, on the other hand, are sets of behaviourally equivalent step sequences, each step being a set of simultaneous actions. Step traces can be represented by relational structures comprising non-simultaneity and weak causality. In this paper, we propose a classification of step alphabets as well as the corresponding step traces and relational structures representing them. We also explain how the original trace model fits into the overall framework.Algorithms and the Foundations of Software technolog
Separation of traces of metal ions from sodium matrices
Method for isolating metal ion traces from sodium matrices consists of two extractions and an ion exchange step. Extraction is accomplished by using 2-thenoyltrifluoracetone and dithizone followed by cation exchange
A Semantics for Tracing
We define a small step operational semantics for a core of Haskell. We modify this semantics to generate traces, specifically Augmented Redex Trails. This small and direct definition of Augmented Redex Trails shall improve our understanding of them and shall help to extend them systematically
WiPal: Efficient Offline Merging of IEEE 802.11 Traces
Merging wireless traces is a fundamental step in measurement-based studies
involving multiple packet sniffers. Existing merging tools either require a
wired infrastructure or are limited in their usability. We propose WiPal, an
offline merging tool for IEEE 802.11 traces that has been designed to be
efficient and simple to use. WiPal is flexible in the sense that it does not
require any specific services, neither from monitors (like synchronization,
access to a wired network, or embedding specific software) nor from its
software environment (e.g. an SQL server). We present WiPal's operation and
show how its features - notably, its modular design - improve both ease of use
and efficiency. Experiments on real traces show that WiPal is an order of
magnitude faster than other tools providing the same features. To our
knowledge, WiPal is the only offline trace merger that can be used by the
research community in a straightforward fashion.Comment: 6 page
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