Filters








65,436 Hits in 6.6 sec

Finding Collisions for a 45-Step Simplified HAS-V [chapter]

Nicky Mouha, Christophe De Cannière, Sebastiaan Indesteege, Bart Preneel
2009 Lecture Notes in Computer Science  
Techniques for improving NL-characteristics are laid out in Sect. 4, where good NL-characteristics for a 45-step simplified HAS-V are obtained as well.  ...  Using this method, we found a characteristic for a 45-step collision with an expected work factor of 2 75.84 step function evaluations, which is given in Table 12 .  ...  For 45 steps of this simplified HAS-V, an NL-characteristic is constructed, requiring about 2 51.53 step function evaluations, or about 2 46 compression function evaluations, to find a collision.  ... 
doi:10.1007/978-3-642-10838-9_16 fatcat:usetvheq2nbixhueg3ghdfvxna

Collision Detection and Trajectory Planning for Palletizing Robots Based OBB

Ali Joodi Jasim Aalhasan, Tang XiaoQi, Song Bao
2016 Indonesian Journal of Electrical Engineering and Computer Science  
This paper proposes an algorithm for Collision detection between two convex polyhedra (Boxes).  ...  The key factor for detecting collision between two OBB convex polyhedra is the Separating Axes Theorem (SAT).  ...  For that, divide the rotation and the total translation into steps, and detecting collision in each step, if there is no collision; continue adding distance and checking again the new step... and so on  ... 
doi:10.11591/ijeecs.v1.i1.pp109-118 fatcat:fgqe7z25lrhabkmeesafsh24ya

Radiation dynamics in fast soliton collisions in the presence of cubic loss [article]

Avner Peleg, Debananda Chakraborty
2019 arXiv   pre-print
be employed for soliton collisions in the presence of dissipative perturbations.  ...  Additional numerical simulations with four simplified NLS models show that the differences between perturbation theory and simulations for intermediate β values are due to the effects of Kerr nonlinearity  ...  In the first step of the perturbation procedure, we find a soliton solution to the single-pulse propagation problem, either in an exact form [23] , or in an approximate form, by a perturbation expansion  ... 
arXiv:1907.08664v1 fatcat:4yixneb7engq7p5i2tnekkcpha

Finding Good Differential Patterns for Attacks on SHA-1 [chapter]

Krystian Matusiewicz, Josef Pieprzyk
2006 Lecture Notes in Computer Science  
Finally, we present a number of patterns of different lengths suitable for finding collisions and near-collisions and discuss some bounds on minimal weights of them.  ...  We show that the problem of finding optimal differential patterns for SHA-1 is equivalent to the problem of finding minimal weight codeword in a linear code.  ...  Biham and Chen were able to find patterns that allowed for finding collisions for variants reduced to first 34 and 36 steps [2] .  ... 
doi:10.1007/11779360_14 fatcat:uphd5w4cond6li7hahikoz5gvy

The Grover energy transfer algorithm for relativistic speeds

Juan Carlos García-Escartín, Pedro Chamorro-Posada
2010 Journal of Physics A: Mathematical and Theoretical  
We show that in a relativistic setting the efficiency of this procedure can be improved. We will consider the transfer of relativistic kinetic energy in a series of elastic collisions.  ...  Grover's algorithm for quantum search can also be applied to classical energy transfer.  ...  If we take v 0 = 1 − x and v ′ 2 = 1 − y, for x, y << 1 and assume N >> 1, we can subtract the equations and find a single step velocity v ss 0 = 1 − 2 N 2 .  ... 
doi:10.1088/1751-8113/43/45/455301 fatcat:6b5ydco6offzdk7mgri663ohky

An entropy based thermalization scheme for hybrid simulations of Coulomb collisions

L.F. Ricketson, M.S. Rosin, R.E. Caflisch, A.M. Dimits
2014 Journal of Computational Physics  
We formulate and test a hybrid fluid-Monte Carlo scheme for the treatment of elastic collisions in gases and plasmas.  ...  It gives a significant performance improvement (e.g., error for a given computational effort) over the velocity-based scheme.  ...  David Levermore for their valuable input regarding this work.  ... 
doi:10.1016/j.jcp.2014.04.059 fatcat:qfi6qh6zl5cwzimb2dc7ahopni

Efficient motion planning for humanoid robots using lazy collision checking and enlarged robot models

Nikolaus Vahrenkamp, Tamim Asfour, Rudiger Dillmann
2007 2007 IEEE/RSJ International Conference on Intelligent Robots and Systems  
To give the robot the ability of acting and navigating in complex environments, the motion planner has to find collision-free paths in a robust manner.  ...  The runtime of a planning algorithm is critical, since complex tasks require several planning steps where the collision detection and avoidance should be accomplished in reasonable time.  ...  For a given start and goal configuration, the planner has to find a path through the C-space while avoiding sample points which belong to C obst .  ... 
doi:10.1109/iros.2007.4399240 dblp:conf/iros/VahrenkampAD07 fatcat:kvdpzbomfzcplb6aqpda6rd5yq

Collision detection with relative screw motion

Samuel R. Buss
2005 The Visual Computer  
We introduce a framework for collision detection between a pair of rigid polyhedra.  ...  This is useful for handling multiple (nearly) concurrent collisions and contact points. The relative motions of the rigid bodies are limited to screw motions.  ...  (In any event, a rotation of 45 • is quite large for a single step of a simulation, and frequently rotations need to clamped to be less than 45 • per simulation step to have stable physical simulations  ... 
doi:10.1007/s00371-004-0269-8 fatcat:zawdkbb35fhe7bjvvtrwkdgmoe

Kinetics of Filament Bundling with Attractive Interactions

Xueping Yu, A.E. Carlsson
2004 Biophysical Journal  
We study the kinetics of filament bundling by variable time-step Brownian-dynamics simulations employing a simplified attractive potential based on earlier atomic-level calculations for actin filaments  ...  R ij is the distance between the centers of i and j; R d is a decay length (R d ¼ 7 Å ); R max is the distance cutoff for this short-ranged interaction; and H(x) is  ...  Then we extract the encounters of u , 45°, and find an average size of 10.5, very close to the global average 10.7.  ... 
doi:10.1529/biophysj.104.047373 pmid:15377526 pmcid:PMC1304882 fatcat:nmvjpztusfe73ffckiwhcc4nuu

Virtual Adversarial Humans finding Hazards in Robot Workplaces [article]

Tom P. Huck, Christoph Ledermann, Torsten Kröger
2021 arXiv   pre-print
We propose a new approach that frames hazard analysis as a search problem in a dynamic simulation environment.  ...  Our goal is to identify workplace hazards by searching for simulation sequences that result in hazardous situations.  ...  ACKNOWLEDGMENT The authors thank Tamim Asfour for fruitful discussions and valuable thought impulses.  ... 
arXiv:2103.00973v1 fatcat:oiuxhcyk2bhdji6n6tjignrbgi

A self-consistent kinetic plasma model with rapid convergence

W.N.G. Hitchon, T.J. Sommerer, J.E. Lawler
1991 IEEE Transactions on Plasma Science  
D Almost any ad hoc assumption made to simplify a discharge model tends to omit vital physical effects.  ...  A numerical calculation has been developed [1]-[4], which is much faster than finite differences and exhibits less numerical diffusion when applied to solve a kinetic equation (or other transport problems  ...  Lawson for helpful discussions, and the Wisconsin Engineering Research Center for Plasma-Aided Manufacturing for support of some of this work.  ... 
doi:10.1109/27.106804 fatcat:kl3hs5c6yvhrpmxelphhyzwfze

A consistent approach for the treatment of Fermi acceleration in time-dependent billiards

A. K. Karlis, F. K. Diakonos, V. Constantoudis
2012 Chaos  
Although this treatment leads to the correct solution after a sufficiently large number of collisions has been reached, the transient part of the evolution of the PDF is not described.  ...  As a first step, we apply this methodology to the FUM, being the archetype of time-dependent billiards to exhibit Fermi acceleration.  ...  ACKNOWLEDGMENTS This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National  ... 
doi:10.1063/1.3697399 pmid:22757579 fatcat:oyxuxx3qcrddtn56ksu4qqihx4

Practical and Realistic Animation of Cloth

Serkan Bayraktar, Ugur Gudukbay, Bulent Ozguc
2007 2007 3DTV Conference  
In this paper, we propose a system for the practical animation of cloth materials. A mass spring based cloth model is used.  ...  In our case each function evaluation involves finding net forces acting on each mass point, updating bounding volumes, finding surface normal vectors, checking for collisions and self-collisions, and resolving  ...  Collision detection should be accurate, fast, stable, and robust for a simulation to be realistic.  ... 
doi:10.1109/3dtv.2007.4379452 fatcat:7ibuxmsxk5g57jrk4b4m7eioyi

Velocity distribution of a driven inelastic one-component Maxwell gas

V. V. Prasad, Dibyendu Das, Sanjib Sabhapandit, R. Rajesh
2017 Physical review. E  
We determine the tails of the steady state velocity distribution of a driven inelastic Maxwell gas, which is a simple model of a granular gas where the rate of collision between particles is independent  ...  For diffusive driving, where collisions with the wall are modelled by an additive noise, the tails of the velocity distribution is universal only if the noise distribution decays faster than exponential  ...  Some of these experiments find P (v) to be universal with β = 3/2 for a wide range of parameters [21, 24] .  ... 
doi:10.1103/physreve.95.032909 pmid:28415251 fatcat:5y63apv3vjgupg2l4a6iu3mjlu

Optimization-Based Safety Analysis of Obstacle Avoidance Systems for Unmanned Aerial Vehicles

Sivaranjini Srikanthakumar, Cunjia Liu, Wen Hua Chen
2011 Journal of Intelligent and Robotic Systems  
Based on a simplified 4 Degree of Freedom (4DoF) kinematic and dynamic model of a UAV, the path planning and collision avoidance algorithms are developed in 3D.  ...  The artificial potential field method is chosen as a path planning and obstacle avoidance candidate technique for verification study as it is a simple and widely used method.  ...  The UAV has to find a collision-free path between the departure and the destination configurations in a static and a dynamic environment containing various obstacles.  ... 
doi:10.1007/s10846-011-9586-0 fatcat:qxdwfaxmjfcq3ilafsjkspphmy
« Previous Showing results 1 — 15 out of 65,436 results