Search results for "Flight"
showing 10 items of 372 documents
A pedagogical flight simulator for longitudinal airplane flight
2009
This article presents a bi-dimensional model of flight and describes the implementation of a flight simulator able to describe the different phases of longitudinal flight of a real airplane. After identifying the relevant physical variables, the equations of motion are written and solved using a numerical integration method. Using computer simulations, flight paths and time evolution of the kinematics variables are analyzed for a complete flight of a light commercial airplane. The simulations take into account and reproduce the basic actions of a pilot to control the flight. The main maneuvers involved in pilotage are also predicted and explained in terms of model parameter variations induc…
Space Thermoacoustic Radioisotopic Power System, SpaceTRIPS: The Magnetohydrodynamic Generator
2021
Electricity production is a major problem for deep space exploration. The possibility of using radioisotope elements with a very long life as an energy source was investigated in the framework of an EU project “SpaceTRIPS”. For this, a two-stage system was tested, the first in which thermal energy is converted into mechanical energy by means of a thermoacoustic process, and the second where mechanical energy is converted into electrical energy by means of a magnetohydrodynamic generator (MHD). The aim of the present study is to develop an analytical model of the MHD generator. A one-dimensional model is developed and presented that allows us to evaluate the behavior of the device as regards…
AUTOMATIC TAKE-OFF OR LANDING PATH FOLLOWING IN TURBULENT AIR FOR UAS - AN EKF BASED PROCEDURE
2015
By using the Extended Kalman Filter (EKF) an accurate take-off or landing flight path following in turbulent air is performed. The tuned up procedure employs simultaneously two different EKF: the first one estimates gust disturbances, the second one affords to determine the necessary controls displacements for rejecting those ones. In particular, the first filter, by using instrumental measurements gathered in turbulent air, estimates wind components. The second one obtains command laws able to follow the desired flight path. To perform this task aerodynamic coefficients have been modified by adding entirely new derivatives or synthetic increments to basic ones whose might the kind of chang…
Multi-scale analysis of the European airspace using network community detection
2014
We show that the European airspace can be represented as a multi-scale traffic network whose nodes are airports, sectors, or navigation points and links are defined and weighted according to the traffic of flights between the nodes. By using a unique database of the air traffic in the European airspace, we investigate the architecture of these networks with a special emphasis on their community structure. We propose that unsupervised network community detection algorithms can be used to monitor the current use of the airspaces and improve it by guiding the design of new ones. Specifically, we compare the performance of three community detection algorithms, also by using a null model which t…
Gene Regulation and Species-Specific Evolution of Free Flight Odor Tracking in Drosophila
2018
Running title: flight evolution in Drosophila This is an invited contribution to the special issue on Genetics of Adaptation based on a symposium of the same name at the National Centre for Biological Sciences (TIFR, Bangalore, India) in November 2016; International audience; The flying ability of insects has coevolved with the development of organs necessary to take-off from the ground, generate, and modulate lift during flight in complex environments. Flight orientation to the appropriate food source and mating partner depends on the perception and integration of multiple chemical signals. We used a wind tunnel-based assay to investigate the natural and molecular evolution of free flight …
The impact of neuroendocrine stress response on cognitive emotion regulation
2016
Commercial and financial policies in family firms: The small business growth management flight simulator
2000
An interactive learning environment (ILE) was built to reproduce the budgeting process of a small family-owned entrepreneurial firm and to capture how current decisions affect business growth in a longer time horizon. The ILE matches the accounting-related perspective through which spreadsheet-based budgets are drawn up, with the system dynamics (SD) view. Such a goal has been pursued through a connection of traditional Excel spreadsheets with POWERSIM SD models. Playing the SMALL BUSINESS GROWTH MANAGEMENT FLIGHT SIMULATOR allows one to learn how (a) to draw up a budget based on an SD perspective, (b) long-term goals may be affected by current decisions, (c) business/family survival and gr…
Dendrites are dispensable for basic motoneuron function but essential for fine tuning of behavior.
2014
Dendrites are highly complex 3D structures that define neuronal morphology and connectivity and are the predominant sites for synaptic input. Defects in dendritic structure are highly consistent correlates of brain diseases. However, the precise consequences of dendritic structure defects for neuronal function and behavioral performance remain unknown. Here we probe dendritic function by using genetic tools to selectively abolish dendrites in identified Drosophila wing motoneurons without affecting other neuronal properties. We find that these motoneuron dendrites are unexpectedly dispensable for synaptic targeting, qualitatively normal neuronal activity patterns during behavior, and basic …
Rural futures in developed economies: The case of Finland
2015
Abstract This study presents four possible images of rural futures in Finland: decentralized bio-economy, colonial countryside, museum countryside and rural business islets. They are distilled through literature reviews, futures workshops and futures tables. Alternative specifications of structures, contents and agencies result in highly divergent states of key dimensions and, consequently, divergent rural futures. This diversity challenges the conventional public wisdom or intellectual monoculture that considers decay as the only future for rural areas. Key challenges in crafting plausible but divergent futures images are finding an appropriate level of abstraction or “flight altitude”, es…
Trajectory tracking for an Ultralight WIG
2007
In this paper we present our research about a particular ultralight WIG. We have carried out the design of a Flight Control System that has to fix the control variables trend through a non-linear mathematical model, because of the particular geometric and aerodynamic configuration of this WIG. So, the non-linear mathematical model design has to reproduce exactly the aircraft behaviour either OGE or IGE. In particular, through classical semi-empirical relations, analytical equations have been obtained in order to evaluate incidence variations, downwash and upwash angles due to the ground. In the present paper only longitudinal dynamic is considered, because of its peculiarity in WIG's aircra…