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Modelling Framework and Results for a Plug-In-Hybrid 250-Seat Short-Range Aircraft (EXACT Project)
Get PDFAn overview of the 250-seater plug-in-hybrid-electric powered aircraft concept D250-PHEP from the EXACT project
UPPAAL Meets Cognitive Science and Learning: Synthesizing Shared Control for Human-Cyber-Physical Systems
No full textHuman–Cyber–Physical Systems (HCPS) require automation that can share control with human operators while preserving safety.
A key challenge is enabling automation to recognise when and how to intervene or defer control to the human operator, which requires predictive models of human cognitive dynamics.
Although cognitive architectures such as ACT-R provide detailed, executable models of human behaviour, their complexity makes them difficult to integrate with formal reactive synthesis techniques. The presented approach bridges this gap by combining automata learning of cognitive models with game-theoretic controller synthesis in UPPAAL-Tiga.
ACT-R simulations of human perceptual, cognitive, and motor processes are abstracted into finite-state Mealy automata via active automata learning, yielding a learned Human Model that captures admissible human behaviour. This model is embedded into a timed game automaton in which different automation levels correspond to distinct sets of controllable actions. Reactive synthesis is then used to determine, for each design variant, whether safety and performance objectives can be guaranteed while accommodating human behaviour. The resulting controllers are correct-by-construction, ensuring safety, progress, and minimal unnecessary overrides. By integrating model learning, formal synthesis, and verification, the framework provides a systematic, tool-supported methodology for designing adaptive shared-control automation and supports reasoning about partial observability by tailoring the learned model’s observable alphabet
Case Studies in Modeling Cruise-Generated Trailing Vortices
No full textTrailing vortices from jet transport aircraft in high altitude cruising flight, have been measured in high spatiotemporal detail, by a research jet operated by the National Research Council Canada. The vortex locations and circulations, descent rate and vortex core thermodynamic, dynamic, transport and spatial scale characteristics were derived. Also, from these measurements, the background atmospheric state properties of pressure, wind structure, temperature, thermal stratification and turbulence have been established. Selected cases from the measured data have been used to evaluate two versions of the Probabilistic 2-Phase (P2P) wake vortex prediction model. While the default P2P version uses ground-based measurement data to calibrate its probabilistic envelopes, the runtime optimized airborne version P2Pa uses uncertainties of all relevant impact parameters to construct the probabilistic envelopes. Flight and model data have been compared and the suitability of the P2P model versions for onboard wake vortex prediction and warning during cruise have been discussed
CoDiST Support Tools Dokumentation
No full textIn diesem Bericht werden all jene Programme und Tools vorgestellt, die entweder zur Erzeugung von Eingabedaten genutzt werden können oder später mit CoDiST mitlaufen. Des Weiteren gibt es Informationen zu Services, die im Umfeld von CoDiST relevant sein und von anderen Tools genutzt werden können
Techno-economic analysis of decarbonization pathways for a deep-sea container vessel
No full textThis study identifies a cost-effective decarbonization strategy for a deep-sea container vessel to meet the greenhouse gas emission (GHG) reduction targets set by the International Maritime Organization (IMO) and European Union (EU). For assumed scenarios for technology availability and costs until 2040, we assess the techno-economic viability of selected energy-saving technologies and alternative fuels under regulatory constraints. Our findings indicate that, for the considered vessel type, speed reduction, air lubrication, and hull maintenance are the most cost-efficient measures to reduce GHG emissions through 2030, after which stricter regulatory thresholds make it necessary to shift to clean alternative fuels. Among the alternative fuels evaluated, we identify ammonia as the most cost-effective
Developing a Modern Build System for the Earth System Modelling Framework MESSy
No full textThe earth system modelling framework MESSy is a large
Fortran-based software used on high-performance computing (HPC) clusters. On
these systems, software is usually built from source with dedicated configuration for
each cluster. This paper describes the process of replacing the old build system based
on Autoconf by a modern build system based on CMake. CMake offers a higher
abstraction level and better portability across HPC systems and architectures.
We focus on recreating the existing configuration options and build targets (binaries,
libraries) with identical compiler flags and dependencies while improving
the maintainability, the usability, and the compilation time
