957 research outputs found
A grammatical specification of human-computer dialogue
The Seeheim Model of human-computer interaction partitions an interactive application into a user-interface, a dialogue controller and the application itself. One of the formal techniques of implementing the dialogue controller is based on context-free grammars and automata. In this work, we modify an off-the-shelf compiler generator (YACC) to generate the dialogue controller. The dialogue controller is then integrated into the popular X-window system, to create an interactive-application generator. The actions of the user drive the automaton, which in turn controls the application
FairFuzz: Targeting Rare Branches to Rapidly Increase Greybox Fuzz Testing Coverage
In recent years, fuzz testing has proven itself to be one of the most
effective techniques for finding correctness bugs and security vulnerabilities
in practice. One particular fuzz testing tool, American Fuzzy Lop or AFL, has
become popular thanks to its ease-of-use and bug-finding power. However, AFL
remains limited in the depth of program coverage it achieves, in particular
because it does not consider which parts of program inputs should not be
mutated in order to maintain deep program coverage. We propose an approach,
FairFuzz, that helps alleviate this limitation in two key steps. First,
FairFuzz automatically prioritizes inputs exercising rare parts of the program
under test. Second, it automatically adjusts the mutation of inputs so that the
mutated inputs are more likely to exercise these same rare parts of the
program. We conduct evaluation on real-world programs against state-of-the-art
versions of AFL, thoroughly repeating experiments to get good measures of
variability. We find that on certain benchmarks FairFuzz shows significant
coverage increases after 24 hours compared to state-of-the-art versions of AFL,
while on others it achieves high program coverage at a significantly faster
rate
Constructional Tools as the Origin of Cognitive Capacities
It is argued that cognitive capacities can be understood as the outcome of the collective action of a set of agents created by tools that explore possible behaviours and train the agents to behave in such appropriate ways as may be discovered. The coherence of the whole system is assured by a combination of vetting the performance of new agents and dealing appropriately with any faults that the whole system may develop. This picture is shown to account for a range of cognitive capacities, including language
Triple patterns: Compact specifications for the generation of operational triple graph grammar rules
Proceedings of the
Sixth International Workshop on
Graph Transformation and Visual Modeling Techniques
(GT-VMT 2007)Triple Graph Grammars (TGGs) allow the specification of high-level rules modelling the synchronized creation of elements in two graphs related through a correspondence graph. Low-level operational rules are then derived to manipulate concrete graphs. However, TGG rules may become unnecessarily verbose when elements have to be replicated from one graph to the other, and their actual derivation cannot exploit the presence of reoccurring patterns. Moreover they do not take advantage from situations in which a normal creation grammar for one of the graphs exists, from which TGG operational rules can be derived to build the other graph.
We present an approach to generating TGG operational rules from normal ones, reducing the information needed to derive them, through the definition of Triple Patterns, a high-level,
compact, declarative, and visual notation for the description of
admissible structures in a triple graph. Patterns can be expressed with respect to classes defined in a meta-model, and instantiated with derived classes at the model level, thus exploiting the inheritance hierarchies. The application of the generated rules results into the (synchronized or batch) creation of the structures specified in the patterns. We illustrate these concepts by showing their application to the synchronized incremental construction of visual models and of their semantics.This work has been partially sponsored by the Spanish Ministry of Education
and Science with projects MOSAIC (TSI2005-08225-C07-06) and MODUWEB (TIN
2006-09678), and the EC’s Human Potential Programme under contract HPRN-CT-2002-00275,
SegraVis. The authors gratefully thank the referees for their useful suggestion
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