Search results for "aeronautics"
showing 10 items of 148 documents
Determination of the Soret coefficient of magnetic particles in a ferrofluid from the steady and unsteady part of the separation curve
2004
Experiments on the particle separation in a vertical thermodiffusion column are used to investigate the separation (Soret effect) in ferrofluids. The use of a two-sectional column with internal walls of low thermal capacity allows analyzing the initial part of the unsteady separation curves as well as the steady state regime. The Soret coefficient calculated from the measurements of the separation dynamics agrees well with the one found from the steady separation limit reached in long-time experiments especially if the solutal buoyancy is low.
Rainfall timing and runoff: The influence of the criterion for rain event separation
2016
Abstract Rain is not uniform in time and space in semiarid areas and its distribution is very important for the runoff process. Hydrological studies usually divide rainfall into events. However, defining rain events is complicated, and rain characteristics vary depending on how the events are delimited. Choosing a minimum inter-event time (MIT) is a commonly used criterion. Our hypothesis is that there will be an optimal MIT that explains the maximum part of the variance of the runoff, with time to runoff used as a surrogate. The objective is to establish a procedure in order to decide upon this optimal MIT. We developed regressions between time to runoff (T0) and three descriptive variable…
Factors affecting flavor perception in space: Does the spacecraft environment influence food intake by astronauts?
2020
International audience; The intention to send a crewed mission to Mars involves a huge amount of planning to ensure a safe and successful mission. Providing adequate amounts of food for the crew is a major task, but 20 years of feeding astronauts on the International Space Station (ISS) have resulted in a good knowledge base. A crucial observation from the ISS is that astronauts typically consume only 80% of their daily calorie requirements when in space. This is despite daily exercise regimes that keep energy usage at very similar levels to those found on Earth. This calorie deficit seems to have little effect on astronauts who spend up to 12 months on the ISS, but given that a mission to …
Experience from Indoor Fire Search and Rescue Game Design for Technology Testing
2018
No matter how good the fire evacuation plan for a building is, there is a risk of immovable victims being left behind due to smoke obscuration, inhalation of poisonous gasses, or other reasons. Firefighters usually perform the search and rescue for casualties in responding to fire hazards, besides the firefighting. Among of the challenges in the search and rescue operation is how to locate victims, and to keep monitoring the fire development so that it will not accidentally harm the fire personnel. This paper presents a game designed to test a smartphone app’s feature that supports concurrent tracking of indoor victims and fire spread. 22 volunteers were assigned roles either as rescuers or…
Science in space vs space science: The European utilisation of spacelab∗
1999
Abstract Spacelab is the conventional name given to a manned laboratory to be carried onboard NASA's Space Shuttle, which was built in Europe under the aegis of the European Space Agency (ESA). This paper deals with the initiatives undertaken in Europe to establish a utilisation programme for Spacelab, in particular for its first flight, planned as a joint ESA/NASA demonstration mission. Two main factors will be discussed, which prevented ESA from establishing a sizeable Spacelab utilisation effort. Firstly, owing to the cost escalation of the Spacelab development programme and to NASA's charging policy for access to the Shuttle system, which did not foressee any preferential treatment to E…
Dynamic Modeling and Driving Cycle Prediction for a Racing Series Hybrid Car
2014
International audience; This paper presents Noao, a plug-in series hybrid racing car equipped with an engine/generator set as range extender. To determine the velocity profile, i.e., performance of the car and its power profile, a dynamic model for this car is developed using pedal position as input. This value is easy to measure, representative for race cycles, and presents a novelty. The model is validated with the results from experiments. An analysis based on the map of Magny-Cours racing circuit and drivers pedal action on certain zones of the circuit is formulated and is used as a prediction tool to determine drivers inputs on other racing circuits and generate driving schedules. The …
Development of a modular room-temperature hydride storage system for vehicular applications
2016
The subject of this paper concerns the development of a vehicular hydrogen tank system, using a commercial interstitial metal hydride as storage material. The design of the tank was intended to feed a fuel cell in a light prototype vehicle, and the chosen hydride material, Hydralloy C5 by GfE, was expected to be able to absorb and desorb hydrogen in a range of pressure suitable for this purpose. A systematic analysis of the material in laboratory scale allows an extrapolation of the thermodynamic and reaction kinetics data. The following development of the modular tank was done according to the requirements of the prototype vehicle propulsion system and led to promising intermediate results…