Equivalence checking for weak bi-Kleene algebra

Pomset automata are an operational model of weak bi-Kleene algebra, which describes programs that can fork an execution into parallel threads, upon completion of which execution can join to resume as a single thread. We characterize a fragment of pomset automata that admits a decision procedure for language equivalence. Furthermore, we prove that this fragment corresponds precisely to series-rational expressions, i.e., rational expressions with an additional operator for bounded parallelism. As a consequence, we obtain a new proof that equivalence of series-rational expressions is decidable

HSPB1, HSPB6, HSPB7 and HSPB8 Protect against RhoA GTPase-Induced Remodeling in Tachypaced Atrial Myocytes

BACKGROUND: We previously demonstrated the small heat shock protein, HSPB1, to prevent tachycardia remodeling in in vitro and in vivo models for Atrial Fibrillation (AF). To gain insight into its mechanism of action, we examined the protective effect of all 10 members of the HSPB family on tachycardia remodeling. Furthermore, modulating effects of HSPB on RhoA GTPase activity and F-actin stress fiber formation were examined, as this pathway was found of prime importance in tachycardia remodeling events and the initiation of AF. METHODS AND RESULTS: Tachypacing (4 Hz) of HL-1 atrial myocytes significantly and progressively reduced the amplitude of Ca²⁺ transients (CaT). In addition to HSPB1, also overexpression of HSPB6, HSPB7 and HSPB8 protected against tachypacing-induced CaT reduction. The protective effect was independent of HSPB1. Moreover, tachypacing induced RhoA GTPase activity and caused F-actin stress fiber formation. The ROCK inhibitor Y27632 significantly prevented tachypacing-induced F-actin formation and CaT reductions, showing that RhoA activation is required for remodeling. Although all protective HSPB members prevented the formation of F-actin stress fibers, their mode of action differs. Whilst HSPB1, HSPB6 and HSPB7 acted via direct prevention of F-actin formation, HSPB8-protection was mediated via inhibition of RhoA GTPase activity. CONCLUSION: Overexpression of HSPB1, as well as HSPB6, HSPB7 and HSPB8 independently protect against tachycardia remodeling by attenuation of the RhoA GTPase pathway at different levels. The cardioprotective role for multiple HSPB members indicate a possible therapeutic benefit of compounds able to boost the expression of single or multiple members of the HSPB family

Networked simulators: effects on the perceptual validity of traffic in driving simulators [Genetwerkte simulatoren: effecten op de perceptuele kwaliteit van verkeer in rijsimulatoren]

Simulators have been used as a tool for training for many decades, and they are still gaining importance. Originally built for stand-alone use, the emergence of (global) network communication allowed these simulators to be connected with other simulators. This introduced the possibility of practicing large, complex exercises with multiple participants. Networked simulation started with SIMNET (Miller & Thorpe, 1995), the first interconnection test bed, and the Distributed Interactive Simulation protocol (DIS), the first generally accepted protocol for data communication between simulators. To minimize the effects of network communication (limited bandwidth, delay), the DIS protocol allows the use of dead reckoning. Using dead reckoning, network load and the effects of delay can be reduced

Ecodriver. D42.1 Performance Indicators and acceptance analysis plan

This deliverable provides a report of the work conducted in Work Package 42.1: Adapting tool for assessing acceptance. The tasks required the identifications of the state-of-the art in the field of acceptance and the development of tools for assessing the performance indicators related to acceptance with respect to the ecoDriver applications. The output of this stage of the ecoDriver project has been a set of standardised questionnaires to be used across all Partners. These questionnaires will be adapted for the different systems, as appropriate

Visual support in operating unmanned aerial vehicles

Op basis van inherente systeemkennis van een MUAV kan direct waarneembare visuele informatie in de vorm van een grid gegenereerd worden. Dit kan compenseren voor beelden met een lage opfrisfrequentie

Human Performance Assessment in Driving Simulators Phase 1 : Theoretical Backgrounds

In theorie zijn rijsimulatoren ideaal om te bepalen hoe goed een bestuurder de rijtaken uitvoert. Rijsimulatoren zijn betrouwbaar en beoordelen prestaties objectief. Bovendien wordt het gedrag beoordeeld in een omgeving die sterk lijkt op de echte rijtaak, wat de validiteit van de beoordeling ten goede komt. Een ander belangrijk voordeel van simulatoren is dat we precies weten welke verkeerssituaties aan een kandidaat voorgelegd worden. Bij toetsing in de praktijk is men altijd afhankelijk van wat zich tijdens een rit voordoet, in de simulator wéét men dat er op de volgende kruising een auto van rechts komt. Dit rapport geeft een verslag van de werkzaamheden in fase 1 van het EZ cofinancieringsproject ‘Toetsing in simulatoren’. In dit driejarig project ontwikkelen we een geautomatiseerde performance assessment module voor rijsimulatoren. Partners in deze fase waren Cito, ANWB rijopleiding, Rozendom Technology en CBR. De ambitie van het cofinancieringsproject gaat verder dan rijsimulatoren alleen. Het project is de eerste stap in de ontwikkeling van een generieke assessment module voor verschillende typen simulatoren