Search results for " and Control"
showing 10 items of 385 documents
Harmonic Balance Method and Stability of Discontinuous Systems
2019
The development of the theory of discontinuous dynamical systems and differential inclusions was not only due to research in the field of abstract mathematics but also a result of studies of particular problems in mechanics. One of first methods, used for the analysis of dynamics in discontinuous mechanical systems, was the harmonic balance method developed in the thirties of the 20th century. In our work the results of analysis obtained by the method of harmonic balance, which is an approximate method, are compared with the results obtained by rigorous mathematical methods and numerical simulation. peerReviewed
The Computer Control Software for MAMI
1980
The computer control system of the Mainz Microtron is designed to keep track with the modular and step-by-step construction of the three accelerator stages. The system is up to now based on two loosely coupled HP1000 minicomputers, interfaced via CAMAC to the accelerator components and to the operator desk. The control software is divided into several layers of portable processes distributed to both computers. Communication between the processes, access to the data bank and the routing of CAMAC interrupts are handled via a message system which operates with symbolic addresses.
Energy Efficient Optimization for Solar-Powered UAV Communications System
2021
In this work, we explore the energy efficiency optimization for a solar-powered unmanned aerial vehicle (UAV) communications system. We consider a scenario where a number of ground users (GUs) connect with a solar-powered multi-antenna UAV over a wireless link. First, we are able to derive the relations between the uplink data rate and heading angle of UAV and transmission power of GUs. In addition, the harvested energy from solar light is also affected by UAV’s angle. Accordingly, with the objective to maximize the energy efficiency that is related to uplink data rate and energy consumption, we propose to dynamically adjust the UAV trajectory and gesture, by optimizing its velocity, accele…
Design of the Biotechnological System for the Cultivation of a Polysaccharide-Producing Microorganism and Metabolites Separation
1970
This paper presents a design of the biotechnological system established for the cultivation of a polysaccharide-producing microorganism and the separation of the polysaccharide together with other metabolites. The strain used is a halophilic archaeon called Haloferax mediterranei (Mironescu et al., 2003). On designing the biotechnological system, some requirements are important: The recipients and the pipes must be resistant to the corrosion action of the cultivation substrate very rich in NaCl (125 to 150 g/l); A command and control system for pH, temperature and substrate and inoculum feeding is necessary; A system for monitoring dissolved oxygen and gases evacuated from the bioreactor (O…
Second order optimality conditions with applications
2007
International audience; The aim of this article is to present the algorithm to compute the first conjugate point along a smooth extremal curve. Under generic assump- tions, the tra jectory ceases to be optimal at such a point. An implementation of this algorithm, called cotcot, is available online and based on recent devel- opments in geometric optimal control. It is applied to analyze the averaged optimal transfer of a satellite between elliptic orbits.
Second order optimality conditions in optimal control with applications
2006
The aim of this article is to present the algorithm to compute the first conjugate point along a smooth extremal curve. Under generic assumptions, the trajectory ceases to be optimal at such a point. An implementation of this algorithm, called \texttt{cotcot}, is available online and based on recent developments in geometric optimal control. It is applied to analyze the averaged optimal transfer of a satellite between elliptic orbits.
Gestión del cuerpo y planificación urbana: Desplazamiento de significado en la reivención de cuepos y ciudades
2020
Contemporary cities have administrations increasingly marked by urban planning guidelines that are guided by business and marketing and, to attract investments and tourists, implement strategies that aim to homogenize, spectacularize and control urban space. However, other experiences in the city potentially build new meaning to it, which would escape those strategically planned, creating alternative possibilities of uses, diverging from the way thar are predicted and proposed by the governmental power in their urban marketing strategies. The article discusses how the occupation of urban spaces by transvestites for prostitution may imply reflections on the role of norms of gender in the (re…
Face mask use in the Community for Reducing the Spread of COVID-19: a systematic review
2021
ABSTRACTBackgroundEvidence is needed on the effectiveness of wearing face masks in the community to prevent SARS-CoV-2 transmission.MethodsSystematic review and meta-analysis to investigate the efficacy and effectiveness of face mask use in a community setting and to predict the effectiveness of wearing a mask. We searched MEDLINE, EMBASE, SCISEARCH, The Cochrane Library and pre-prints from inception to 22 April 2020 without restriction by language. We rated the certainty of evidence according to Cochrane and GRADE approach.FindingsOur search identified 35 studies, including 3 randomised controlled trials (RCTs) (4017 patients), 10 comparative studies (18984 patients), 13 predictive models,…
Opinion dynamics and stubbornness through mean-field games
2013
This paper provides a mean field game theoretic interpretation of opinion dynamics and stubbornness. The model describes a crowd-seeking homogeneous population of agents, under the influence of one stubborn agent. The game takes on the form of two partial differential equations, the Hamilton-Jacobi-Bellman equation and the Kolmogorov-Fokker-Planck equation for the individual optimal response and the population evolution, respectively. For the game of interest, we establish a mean field equilibrium where all agents reach epsilon-consensus in a neighborhood of the stubborn agent's opinion.
Remdesivir for the Treatment of Hospitalised Patients with COVID-19 (DisCoVeRy): A Randomised, Controlled, Open-Label Trial
2021
Background: The antiviral efficacy of remdesivir is still controversial. We aimed at evaluating its clinical effectiveness in patients with COVID-19 requiring oxygen and/or ventilator support. Methods: In this European multicentre, open-label, parallel-group, randomised, controlled trial in adults hospitalised with COVID-19 (DisCoVeRy, NCT04315948; EudraCT2020-000936-23), participants were randomly allocated to receive usual standard of care alone or in combination with intravenous remdesivir (200 mg on day 1, then 100 mg once-daily for 9 days or until discharge). Treatment assignation was performed via web-based randomisation stratified on illness severity and administrative European regio…