Paradoxe des jumeaux

VDMNav: Software Architecture for Aerodynamically Constrained Navigation on Small Fixed-Wing Drones

Jan Skaloud, Aman Sharma, Gabriel François Laupré

Navigation of drones is predominantly based on sensor fusion algorithms. Most of these algorithms make use of some form of Bayesian filtering with a majority employing an Extended Kalman Filter (EKF), wherein inertial measurements are fused with a Global N ...

2024

Evolution of deformation twinning mechanisms in magnesium from low to high strain rates

Roland Logé, Cyril Cayron, Johann Michler, Xavier Maeder, Nicolò Maria Della Ventura

We present a systematic investigation of {10 (1) over bar2} extension twinning mechanism in single crystal magnesium micropillars deformed over seven orders of magnitude of strain rate, from 10(-4) to 500 s(-1), revealing how the accommodation of newly for ...

ELSEVIER SCI LTD2022

R&D offshoring and home industry productivity

Gaétan Jean A de Rassenfosse

Offshoring research and development (R&D) commonly invokes concerns regarding the loss of high value jobs and a hollowing out of technological capabilities, but it can also benefit domestic firms by enabling them to tap into the global technological fronti ...

OXFORD UNIV PRESS2019

Optimal Stochastic Sensor Error Modeling based on Actual Impact on Quality of GNSS-INS Integrated Navigation

Jan Skaloud, Stéphane Guerrier, Mehran Khaghani

Proper modeling of stochastic errors in inertial sensors plays a crucial role in the achievable quality of GNSS-INS integration especially with low-cost inertial sensors. Generalized Method of Wavelet Moments (GMWM) can model the underlying process for suc ...

2019

Hard-sphere displacive model of deformation twinning in hexagonal close-packed metals. Revisiting the case of the (56, a) contraction twins in magnesium

Cyril Cayron

Contraction twinning in magnesium alloys leads to new grains that are misoriented from the parent grain by a rotation (56°, a). The classical shear theory of deformation twinning does not specify the atomic displacements and does not explain why contractio ...

Int Union Crystallography2017

The rod and hole paradox re-examined

Harald Van Lintel, Christian Gruber

In the rod and hole paradox as described by Rindler (1961 Am. J. Phys. 29 365–6) ('length contraction paradox'), a rigid rod moves at high speed over a table towards a hole of the same size. A bystander expects the rod to fall into the hole, but a co-movin ...

2005