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Advances in air to air refuelling

Peter R. Thomas, Ujjar Bhandari, Steve Bullock, Thomas S. Richardson, Jonathan L. du Bois
2014 Progress in Aerospace Sciences  
Follow up development in [85] allows both tanker and receiver to perform precision navigation independently using precision ephemeris correction updates for the GPS signals.  ...  A geometric waypoint estimator along with a collaborative autonomous rendezvous controller was used to generate the heading rate and acceleration commands by using a heading and a time-of-arrival control  ... 
doi:10.1016/j.paerosci.2014.07.001 fatcat:roclwvz5rjgifjcxup2jewoayi

Improved Indirect Method for Air-Vehicle Trajectory Optimization

Roger L. Barron, Cleon M. Chick
2006 Journal of Guidance Control and Dynamics  
Although the search performance response surfaces remain multi- modal, it is feasible to use arbitrary first iterates in a probabilistically controlled, multiple-thread, costate search algorithm for initializing  ...  Integration time steps of 0.1 s were used for trajectory shooting and 0.01 s for refined calculations.  ... 
doi:10.2514/1.16228 fatcat:7hxs2rv33bbudc22ovbmb7ml3q

Computational Air Traffic Management

Marc Anthony Azzopardi, James F. Whidborne
2011 2011 IEEE/AIAA 30th Digital Avionics Systems Conference  
The traffic density using such a system can be realistically increased many times higher than current levels while significantly improving on the current levels of safety, operating cost, environmental  ...  This work advances the field of ATM as well as the fields of Computational Intelligence and Dynamic Optimisation of High Dimensionality Non-Convex Search Spaces. iii DEDICATIONS To my brother Carl, my  ...  arbitrary cost functional .  ... 
doi:10.1109/dasc.2011.6095967 fatcat:5kfu6ba5h5g7pdffh7z3ftdjai

Mid-Air Pointing on Ultra-Walls

Mathieu Nancel, Emmanuel Pietriga, Olivier Chapuis, Michel Beaudouin-Lafon
2015 ACM Transactions on Computer-Human Interaction  
We then explore solutions to improve mid-air pointing efficiency: a tunable acceleration function and a framework for dual-precision techniques, both with precise tuning guidelines.  ...  Despite the widespread use of Pointer Acceleration, there is very little literature on how to design effective transfer functions for specific input and output systems such as ultra-walls.  ...  Pointer Acceleration consists in applying a transfer function to the Control-Display gain based on the dynamics of the users' movements.  ... 
doi:10.1145/2766448 fatcat:a7p3p2qv2zbeno6r66ucrq26va

Air-Combat Strategy Using Approximate Dynamic Programming

James S. McGrew, Jonathon P. How, Brian Williams, Nicholas Roy
2010 Journal of Guidance Control and Dynamics  
This paper presents a formulation of a level flight, fixed velocity, one-on-one air combat maneuvering problem and an approximate dynamic programming (ADP) approach for computing an efficient approximation  ...  An accompanying fast and effective rollout based policy extraction method is used to accomplish on-line implementation.  ...  For example, Virtanen et al. 7 modeled air combat using an influence diagram, which could be solved using dynamic programming.  ... 
doi:10.2514/1.46815 fatcat:bc4tuiqsunb53irm5ooxknpigq

Trajectory Optimization for Air-to-Surface Missiles with Imaging Radars

Asif Farooq, David J. N. Limebeer
2002 Journal of Guidance Control and Dynamics  
In this study, the computations were performed using double-precision arithmetic on a Sun SPARC workstation.  ...  The threshold height is assumed to be the height at which the missile becomes exposed to air defense systems and is otherwise arbitrary. This is shown in two dimensions in Fig. 1.  ... 
doi:10.2514/2.4981 fatcat:ma6k46pktfh4ngowinf6uqf6oe

Air Combat Maneuvering Performance Measurement

Michael J. Kelly, A. Lee Wooldridge, Robert T. Hennessy, John C. Reed
1979 Proceedings of the Human Factors Society Annual Meeting  
The measure set should be refined through iterative computer analyses of the existing data base.  ...  Future iterations of the analysis process and the addition of diagnostic measures could be expected to further refine the measurement structure and improve this accuracy.  ...  Accelerate in the 45 degree dive to 400 Knots, then pull up to enter a 3 g/500 Knots level turn right. Do this on instruments. Any questions? 2. Second Run.  ... 
doi:10.1177/107118137902300183 fatcat:uh7k6hbwvjbsfow6yvvqgvlf6u

Relative navigation of autonomous GPS-degraded micro air vehicles

David O. Wheeler, Daniel P. Koch, James S. Jackson, Gary J. Ellingson, Paul W. Nyholm, Timothy W. McLain, Randal W. Beard
2020 Autonomous Robots  
Many current approaches for navigation of micro air vehicles (MAVs) in GPS-degraded environments use a globally-referenced state for estimation and control, even though this state is not observable when  ...  This map is used to demonstrate autonomous completion of mission objectives.  ...  Introduction Economists anticipate that autonomous micro air vehicles (MAVs) will give rise to a handful of billion-dollar markets, including infrastructure inspection, security, precision agriculture,  ... 
doi:10.1007/s10514-019-09899-4 fatcat:x6otjuozbnbpljanjrah4bc2c4

Air to ground quantum key distribution

Sebastian Nauerth, Florian Moll, Markus Rau, Joachim Horwath, Stefan Frick, Christian Fuchs, Harald Weinfurter, Ronald E. Meyers, Yanhua Shih, Keith S. Deacon
2012 Quantum Communications and Quantum Imaging X  
This proves for a precise compensation of the polarization rotations in the quantum channel.  ...  Moreover, a key, once generated using QKD, can be analyzed for its integrity and discarded -in parts or completely -in case the transmission was intercepted.  ...  On d b , the pointing and tracking could also be tried dynamically with the test vehicle accelerating on about 100 m. The inset shows the FELT2 mounted on the lab trolley in the car.  ... 
doi:10.1117/12.929790 fatcat:u4qxuy7lvffxrdnmtxqe7yj27q

A neural-network based control solution to air-fuel ratio control for automotive fuel-injection systems

C. Alippi, C. de Russis, V. Piuri
2003 IEEE Transactions on Systems Man and Cybernetics Part C (Applications and Reviews)  
An indirect control approach has been considered which requires a preliminary modeling of the engine dynamics.  ...  Requirements for feasible control actions and the static precision of control have been integrated in the controller design to guide learning toward an effective control solution.  ...  Online training must not necessarily be continuous but must be enabled to refine the controller only when required.  ... 
doi:10.1109/tsmcc.2003.814035 fatcat:ygwajz3clzdy5py5uqazhepxfy

Calibrating airborne measurements of airspeed, pressure and temperature using a Doppler laser air-motion sensor

W. A. Cooper, S. M. Spuler, M. Spowart, D. H. Lenschow, R. B. Friesen
2014 Atmospheric Measurement Techniques Discussions  
those measurements to less than 0.3 hPa and the precision applicable to steady flight conditions to about 0.1 hPa.  ...  For airspeed, pressure and temperature, these are significant reductions in uncertainty vs. those obtained from calibrations using standard techniques.  ...  Data used in this study were collected during field campaigns led by S. Wofsy (HIPPO), C. Davis (PREDICT) and J.  ... 
doi:10.5194/amtd-7-2585-2014 fatcat:xpi6eaq3lngylndjniqrdmpfwa

Calibrating airborne measurements of airspeed, pressure and temperature using a Doppler laser air-motion sensor

W. A. Cooper, S. M. Spuler, M. Spowart, D. H. Lenschow, R. B. Friesen
2014 Atmospheric Measurement Techniques  
those measurements to less than 0.3 hPa and the precision applicable to steady flight conditions to about 0.1 hPa.  ...  For airspeed, pressure and temperature, these are significant reductions in uncertainty vs. those obtained from calibrations using standard techniques.  ...  Data used in this study were collected during field campaigns led by S. Wofsy (HIPPO), C. Davis (PREDICT) and J.  ... 
doi:10.5194/amt-7-3215-2014 fatcat:ryk4wrcubzghlazrtuhjkzoouy

Trends in Air Pollution and Mortality

Holly Janes, Francesca Dominici, Scott L. Zeger
2007 Epidemiology  
Warm thanks to Margareta Larsson for providing us with copies of mortality statistics in old publications from Statistics Sweden.  ...  to 50 -69 and without using refined mortality ( Table 1 ).  ...  Weight was measured using calibrated scales at 0.2 kg precision (Seca, Hamburg, Germany). Height was measured with fixed stadiometers at 0.5 cm precision (Seca).  ... 
doi:10.1097/ede.0b013e31806462e9 pmid:17568215 fatcat:j4sjpmdhbbc7lknn33vbcibimm

Adjoint-based control of a new eulerian network model of air traffic flow

A.M. Bayen, R.L. Raffard, C.J. Tomlin
2006 IEEE Transactions on Control Systems Technology  
An Eulerian network model for air traffic flow in the National Airspace System is developed and used to design flow control schemes which could be used by Air Traffic Controllers to optimize traffic flow  ...  Constraints are enforced using a logarithmic barrier. Simulations of actual air traffic data and control scenarios involving several airports between Chicago and the U.S.  ...  Liu helped define the PDE used for this model.  ... 
doi:10.1109/tcst.2006.876904 fatcat:6dmkacva7farnnqiw5grqluj4i

Scale-adaptive morphometric analysis for urban air quality and ventilation applications

Laura S. Leo, Riccardo Buccolieri, Silvana Di Sabatino
2018 Building Research & Information  
Starting from an estimation of aerodynamic parameters, and their validation by computational fluid dynamics using an existing simulation of downtown Oklahoma City in the US, the method is used to evaluate  ...  It is suggested that the grid used for calculation of morphometric parameters provides the best agreement with data from laboratory experiments when the selection of grid size is made upon the spatial  ...  Computational fluid dynamics (CFD) is used as a provider of benchmark data for the establishment of the fluid dynamics relevance of the morphometric parameters.  ... 
doi:10.1080/09613218.2018.1501797 fatcat:vztixy5bwbdzvjyb44s6haycci
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