Search results for "Control system"
showing 10 items of 971 documents
Intelligent Traction Control for Wheeled Space Vehicles
2006
This paper presents the SC-MER, safety control for Mars exploration rover, an innovative traction control scheme for wheeled mobile vehicles. The system is thought to be used on space mission rovers and is based on fuzzy logic and competitive neural networks to achieve optimal navigation on rough terrain with variable morphology. The main goal of this research is to minimize the power consumption needed during the navigation and improve the overall stability and safety of the rover itself
Global sensitivity analysis of the A-SCOPE model in support of future FLEX fluorescence retrievals
2014
In support of ESA's Earth Explorer 8 candidate mission FLEX (FLuorescence EXplorer), a Photosynthesis Study has been initiated to quantitatively link fluorescence to photosynthesis. This led to the development of A-SCOPE, a graphical user interface software package that integrates multiple biochemical models into the soil-vegetation-atmosphere-transfer model SCOPE. Its latest version (v1.53) has been successfully verified and was subsequently evaluated through a global sensitivity analysis. By using the method of Saltelli [4], the relative importance of each input variable to model outputs was quantified through first order and total effect sensitivity indices. Variations in leaf area index…
Improved Upper Limit on the Neutrino Mass from a Direct Kinematic Method by KATRIN
2019
We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic end point at 18.57 keV gives an effective neutrino mass square value of (−1.0−1.1+0.9) eV2. From this, we derive an upper limit of 1.1 eV (90% confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a …
Bayesian Analysis of a Future Beta Decay Experiment's Sensitivity to Neutrino Mass Scale and Ordering
2021
Bayesian modeling techniques enable sensitivity analyses that incorporate detailed expectations regarding future experiments. A model-based approach also allows one to evaluate inferences and predicted outcomes, by calibrating (or measuring) the consequences incurred when certain results are reported. We present procedures for calibrating predictions of an experiment's sensitivity to both continuous and discrete parameters. Using these procedures and a new Bayesian model of the $\beta$-decay spectrum, we assess a high-precision $\beta$-decay experiment's sensitivity to the neutrino mass scale and ordering, for one assumed design scenario. We find that such an experiment could measure the el…
A Study of the Simulated Evolution of the Spectral Sensitivity of Visual Agent Receptors
2001
In this article we study a model for the evolution of the spectral sensitivity of visual receptors for agents in a continuous virtual environment. The model uses a genetic algorithm (GA) to evolve the agent sensors along with the control of the agents by requiring the agents to solve certain tasks in the simulation environment. The properties of the evolved sensors are analyzed for different scenarios. In particular, it is shown that the GA is able to find a balance between sensor costs and agent performance in such a way that the spectral sensor sensitivity reflects the emission spectrum of the target objects and that the capability of the sensors to evolve can help the agents significantl…
Acquisition of competencies with serious games in the accounting field: an empirical analysis
2018
El actual sistema de educación superior se basa en un aprendizaje activo por parte del estudiante enfocado al desarrollo de competencias genéricas y específicas. En este contexto muchos autores defienden el uso de simulaciones que favorezcan dicho aprendizaje y, los denominados «juegos serios» (serious games [SG]) se adaptan a este reto. Sin embargo, el empuje que cabría esperar por el desarrollo de las nuevas tecnologías y de la llegada de los denominados «nativos digitales» a las aulas no es coherente ni con su grado de implantación ni con la escasa investigación desarrollada sobre la efectividad de su uso. Los objetivos de este estudio son describir una experiencia docente de implantació…
Cost analysis for a future helicopter for passenger transport
2015
Purpose - This paper aims to identify the parameters that influence the cost competitiveness of helicopter services for scheduled passenger transport on a regional area. Design/methodology/approach - The approach used is based on an analysis of demand and on a bi-level model (modal split model - service supply optimization model) optimization. Performance optimization in the supply of helicopter transport services is obtained by a sensitivity analysis on the recognized cost factors. Findings - The identification of the variation margins in the cost factors that might make an helicopter competitive for scheduled passenger services. Research limitations/implications - The inability to conside…
Sensitivity of Regional Water Supply Systems Models to the Level of Skeletonization – A Case Study from Apulia, Italy
2015
AbstractSimulation models supported by state-of-the-art software packages are nowadays available to explore operation rules of regional water supply systems or to select structural alternatives for improving long-term service performances.Given the, sometimes high, complexity of these systems, model calibration can become a lengthy procedure and many runs are necessary before obtaining convincing results. However, even after calibration, depending on system's complexity and the number of time steps investigated, a single run can take up to several minutes, even on state-of-the-art computers, so that simulation time can become a true bottleneck if such models are to be coupled with metaheuri…
Interaction Mechanism of Humans in a Cyber-Physical Environment
2015
The research initiative “Industrie 4.0” (I4.0) of the high-tech strategy announced by the German government targets the deployment of a cyber-physical system (CPS) in production and logistics. Such CPS-based environments are characterized by an increasing number of heterogeneous intelligent autonomous and communicating artifacts tightly integrated with humans. Thus, the human’s role will become a composite factor (“man-in-the-mesh”) for this future CPS environment, playing more than just a simple role inside the control loop. This paper investigates the need of a robust communication between CPS and humans, which includes a clear semantic of the exchanged information. For this purpose, a me…
Expert control of DO in the aerobic reactor of an activated sludge process
2000
Abstract An expert control structure is proposed for the control of dissolved oxygen (DO) in a Nitrification Denitrification Biological Excess Phosphorus Removal (NDBEPR) plant to account for the several processes that are influenced by the DO concentration in the aerator. In the scheme a supervisory fuzzy controller determines the set point of an inner DO control loop where an Adaptive Robust Generic Model Control (ARGMC) controller is used. The fuzzy supervisory control has a hierarchical structure. Off-line measurements of biological parameters of influent and effluent streams can be used to periodically update the set points of the fuzzy controllers. The complete control scheme has been…