33,638 research outputs found
Observation and abstract behaviour in specification and implementation of state-based systems
Classical algebraic specification is an accepted framework for specification. A criticism which applies is the
fact that it is functional, not based on a notion of state as most software development and implementation languages
are. We formalise the idea of a state-based object or abstract machine using algebraic means. In contrast to similar approaches we consider dynamic logic instead of equational logic as the framework for specification and implementation. The advantage is a more expressive language allowing us to specify safety and liveness conditions. It also allows a clearer distinction of functional and state-based parts which require different treatment in order to achieve behavioural abstraction when necessary. We shall in particular focus on abstract behaviour and observation. A behavioural notion of satisfaction for state-elements is needed in order to abstract from irrelevant details of the state realisation
The foundational legacy of ASL
Abstract. We recall the kernel algebraic specification language ASL and outline its main features in the context of the state of research on algebraic specification at the time it was conceived in the early 1980s. We discuss the most significant new ideas in ASL and the influence they had on subsequent developments in the field and on our own work in particular.
Introduction to the ISO specification language LOTOS
LOTOS is a specification language that has been specifically developed for the formal description of the OSI (Open Systems Interconnection) architecture, although it is applicable to distributed, concurrent systems in general. In LOTOS a system is seen as a set of processes which interact and exchange data with each other and with their environment. LOTOS is expected to become an ISO international standard by 1988
OpenJML: Software verification for Java 7 using JML, OpenJDK, and Eclipse
OpenJML is a tool for checking code and specifications of Java programs. We
describe our experience building the tool on the foundation of JML, OpenJDK and
Eclipse, as well as on many advances in specification-based software
verification. The implementation demonstrates the value of integrating
specification tools directly in the software development IDE and in automating
as many tasks as possible. The tool, though still in progress, has now been
used for several college-level courses on software specification and
verification and for small-scale studies on existing Java programs.Comment: In Proceedings F-IDE 2014, arXiv:1404.578
Developing an integrated concept for the E-ELT Multi-Object Spectrograph (MOSAIC): design issues and trade-offs
We present a discussion of the design issues and trade-offs that have been
considered in putting together a new concept for MOSAIC, the multi-object
spectrograph for the E-ELT. MOSAIC aims to address the combined science cases
for E-ELT MOS that arose from the earlier studies of the multi-object and
multi-adaptive optics instruments. MOSAIC combines the advantages of a
highly-multiplexed instrument targeting single-point objects with one which has
a more modest multiplex but can spatially resolve a source with high resolution
(IFU). These will span across two wavebands: visible and near-infrared
From RT-LOTOS to Time Petri Nets new foundations for a verification platform
The formal description technique RT-LOTOS has been selected as intermediate language to add formality to a real-time UML profile named TURTLE. For this sake, an RT-LOTOS verification platform has been developed for early detection of design errors in real-time system models. The paper discusses an extension of the platform by inclusion of verification tools developed for Time Petri Nets. The starting point is the definition of RT-LOTOS to TPN translation patterns. In particular, we introduce the concept of components embedding Time Petri Nets. The translation patterns are implemented in a prototype tool which takes as input an RT-LOTOS specification and outputs a TPN in the format admitted by the TINA tool. The efficiency of the proposed solution has been demonstrated on various case studies
Implementation of classical communication in a quantum world
Observations of quantum systems carried out by finite observers who
subsequently communicate their results using classical data structures can be
described as "local operations, classical communication" (LOCC) observations.
The implementation of LOCC observations by the Hamiltonian dynamics prescribed
by minimal quantum mechanics is investigated. It is shown that LOCC
observations cannot be described using decoherence considerations alone, but
rather require the \textit{a priori} stipulation of a positive operator-valued
measure (POVM) about which communicating observers agree. It is also shown that
the transfer of classical information from system to observer can be described
in terms of system-observer entanglement, raising the possibility that an
apparatus implementing an appropriate POVM can reveal the entangled
system-observer states that implement LOCC observations.Comment: 17 pages, 2 figures; final versio
DEMON: a Proposal for a Satellite-Borne Experiment to study Dark Matter and Dark Energy
We outline a novel satellite mission concept, DEMON, aimed at advancing our
comprehension of both dark matter and dark energy, taking full advantage of two
complementary methods: weak lensing and the statistics of galaxy clusters. We
intend to carry out a 5000 sqdeg combined IR, optical and X-ray survey with
galaxies up to a redshift of z~2 in order to determine the shear correlation
function. We will also find ~100000 galaxy clusters, making it the largest
survey of this type to date. The DEMON spacecraft will comprise one IR/optical
and eight X-ray telescopes, coupled to multiple cameras operating at different
frequency bands. To a great extent, the technology employed has already been
partially tested on ongoing missions, therefore ensuring improved reliability.Comment: 12 pages, 3 figures, accepted for publication in the SPIE conference
proceeding
Modal Interface Automata
De Alfaro and Henzinger's Interface Automata (IA) and Nyman et al.'s recent
combination IOMTS of IA and Larsen's Modal Transition Systems (MTS) are
established frameworks for specifying interfaces of system components. However,
neither IA nor IOMTS consider conjunction that is needed in practice when a
component shall satisfy multiple interfaces, while Larsen's MTS-conjunction is
not closed and Bene\v{s} et al.'s conjunction on disjunctive MTS does not treat
internal transitions. In addition, IOMTS-parallel composition exhibits a
compositionality defect. This article defines conjunction (and also
disjunction) on IA and disjunctive MTS and proves the operators to be
'correct', i.e., the greatest lower bounds (least upper bounds) wrt. IA- and
resp. MTS-refinement. As its main contribution, a novel interface theory called
Modal Interface Automata (MIA) is introduced: MIA is a rich subset of IOMTS
featuring explicit output-must-transitions while input-transitions are always
allowed implicitly, is equipped with compositional parallel, conjunction and
disjunction operators, and allows a simpler embedding of IA than Nyman's. Thus,
it fixes the shortcomings of related work, without restricting designers to
deterministic interfaces as Raclet et al.'s modal interface theory does.Comment: 28 page
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