325,533 research outputs found
Automated proof search system for logic of correlated knowledge
The automated proof search system and decidability for logic of correlated
knowledge is presented in this paper. The core of the proof system is the
sequent calculus with the properties of soundness, completeness, admissibility
of cut and structural rules, and invertibility of all rules. The proof search
procedure based on the sequent calculus performs automated terminating proof
search and allows us to achieve decision result for logic of correlated
knowledge
A New Linear Logic for Deadlock-Free Session-Typed Processes
The π -calculus, viewed as a core concurrent programming language, has been used as the target of much research on type systems for concurrency. In this paper we propose a new type system for deadlock-free session-typed π -calculus processes, by integrating two separate lines of work. The first is the propositions-as-types approach by Caires and Pfenning, which provides a linear logic foundation for session types and guarantees deadlock-freedom by forbidding cyclic process connections. The second is Kobayashi’s approach in which types are annotated with priorities so that the type system can check whether or not processes contain genuine cyclic dependencies between communication operations. We combine these two techniques for the first time, and define a new and more expressive variant of classical linear logic with a proof assignment that gives a session type system with Kobayashi-style priorities. This can be seen in three ways: (i) as a new linear logic in which cyclic structures can be derived and a CYCLE -elimination theorem generalises CUT -elimination; (ii) as a logically-based session type system, which is more expressive than Caires and Pfenning’s; (iii) as a logical foundation for Kobayashi’s system, bringing it into the sphere of the propositions-as-types paradigm
The ATLAS barrel level-1 Muon Trigger Sector-Logic/RX off-detector trigger and acquisition board
The ATLAS experiment uses a system of three concentric layers of Resistive Plate Chambers (RPC) detector for the Level-1 Muon Trigger in the air-core barrel toroid region. The trigger algorithm looks for hit coincidences within different detector layers inside the programmable geometrical road which defines the transverse momentum cut. The on-detector electronics that provides the trigger and detector readout functionalities collects input signals coming from the RPC front-end. Trigger and readout data are then sent via optical fibres to the off-detector electronics. Six or seven optical fibres from one of the 64 trigger sectors go to one Sector-Logic/RX module, that later elaborates the collected trigger and readout data, and sends data respectively to the Read-Out Driver modules and to the Central Level-1 Trigger. We present the functionality and the implementation of the VME Sector-Logic/RX module, and the configuration of the system for the first cosmic ray data collected using this module
On the Fair Termination of Client-Server Sessions
Client-server sessions are based on a variation of the traditional
interpretation of linear logic propositions as session types in which
non-linear channels (those regulating the interaction between a pool of clients
and a single server) are typed by coexponentials instead of the usual
exponentials. Coexponentials enable the modeling of racing interactions,
whereby clients compete to interact with a single server whose internal state
(and thus the offered service) may change as the server processes requests
sequentially. In this work we present a fair termination result for
CSLL, a core calculus of client-server sessions. We design a type
system such that every well-typed term corresponds to a valid derivation in
MALL, the infinitary proof theory of linear logic with least and
greatest fixed points. We then establish a correspondence between reductions in
the calculus and principal reductions in MALL. Fair termination
in CSLL follows from cut elimination in MALL
A recovery operator for non-transitive approaches
In some recent articles, Cobreros, Egré, Ripley, & van Rooij have defended the idea that abandoning transitivity may lead to a solution to the trouble caused by semantic paradoxes. For that purpose, they develop the Strict-Tolerant approach, which leads them to entertain a nontransitive theory of truth, where the structural rule of Cut is not generally valid. However, that Cut fails in general in the target theory of truth does not mean that there are not certain safe instances of Cut involving semantic notions. In this article we intend to meet the challenge of answering how to regain all the safe instances of Cut, in the language of the theory, making essential use of a unary recovery operator. To fulfill this goal, we will work within the so-called Goodship Project, which suggests that in order to have nontrivial naïve theories it is sufficient to formulate the corresponding self-referential sentences with suitable biconditionals. Nevertheless, a secondary aim of this article is to propose a novel way to carry this project out, showing that the biconditionals in question can be totally classical. In the context of this article, these biconditionals will be essentially used in expressing the self-referential sentences and, thus, as a collateral result of our work we will prove that none of the recoveries expected of the target theory can be nontrivially achieved if self-reference is expressed through identities.Fil: Barrio, Eduardo Alejandro. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. Instituto de Investigaciones Filosóficas - Sadaf; ArgentinaFil: Pailos, Federico Matias. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. Instituto de Investigaciones Filosóficas - Sadaf; ArgentinaFil: Szmuc, Damián Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. Instituto de Investigaciones Filosóficas - Sadaf; Argentin
Compound Logics for Modification Problems
We introduce a novel model-theoretic framework inspired from graph
modification and based on the interplay between model theory and algorithmic
graph minors. The core of our framework is a new compound logic operating with
two types of sentences, expressing graph modification: the modulator sentence,
defining some property of the modified part of the graph, and the target
sentence, defining some property of the resulting graph. In our framework,
modulator sentences are in counting monadic second-order logic (CMSOL) and have
models of bounded treewidth, while target sentences express first-order logic
(FOL) properties along with minor-exclusion. Our logic captures problems that
are not definable in first-order logic and, moreover, may have instances of
unbounded treewidth. Also, it permits the modeling of wide families of problems
involving vertex/edge removals, alternative modulator measures (such as
elimination distance or -treewidth), multistage modifications, and
various cut problems. Our main result is that, for this compound logic,
model-checking can be done in quadratic time. All derived algorithms are
constructive and this, as a byproduct, extends the constructibility horizon of
the algorithmic applications of the Graph Minors theorem of Robertson and
Seymour. The proposed logic can be seen as a general framework to capitalize on
the potential of the irrelevant vertex technique. It gives a way to deal with
problem instances of unbounded treewidth, for which Courcelle's theorem does
not apply. The proof of our meta-theorem combines novel combinatorial results
related to the Flat Wall theorem along with elements of the proof of
Courcelle's theorem and Gaifman's theorem. We finally prove extensions where
the target property is expressible in FOL+DP, i.e., the enhancement of FOL with
disjoint-paths predicates
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