Random numbers are the nuts and bolts of simulation. Typically, all the randomness required by the model is simulated by a random number generator whose output is assumed to be a sequence of independent and identically distributed (IID) U(0; 1) random variables (i.e., continuous random variables distributed uniformly over the interval (0; 1)). These random numbers are then transformed as needed...

The scattering problem refers to the gossiping and the broadcasting problems 1,2]. It consists in distributing a set of data from a single source such that each component is destinated to a distinct address. The gathering operation is the reverse of the scattering operation. This paper studies the problem of pipelining a scattering-gathering sequence in order to overlap these operations. We rst...

We studied the angular resolution of the Pierre Auger Detector using data collected from January 2004 to May 2005. The detector consists of two independent components, the fluorescence detector and the surface detector. Hybrid events, observed simultaneously by both components, have smaller reconstruction uncertainties than the events observed with only one component. The hybrid resolution is e...

Two new xanthones, characterized as 4-(1,1-dimethylprop-2-enyl)-1,3,5,8-tetrahydroxyxanthone (1) and penangianaxanthone (2), with three known xanthones, cudratricusxanthone H (3), macluraxanthone C (4) and gerontoxanthone C (5), as well as friedelin and stigmasterol were isolated from the leaves of Garcinia penangiana. Their structures were elucidated by analysis of spectroscopic data and compa...

The Pierre Auger Observatory aims to discover the nature and origins of the 24 highest energy cosmic rays. The large number of physicists involved in the project and 25 the diversity of simulation and reconstruction tasks pose a challenge for the offline analysis 26 software, not unlike the challenges confronting software for very large high energy physics 27 experiments. Previously we have rep...

We present a new approach to path planning, called the \Ariadne's clew algorithm". It is designed to nd paths in high-dimensional continuous spaces and applies to robots with many degrees of freedom in static, as well as dynamic environments | ones where obstacles may move. The Ariadne's clew algorithm comprises two sub-algorithms, called search and explore, applied in an interleaved manner. ex...

Historical account of the early development of Fourier Transform Spectrometry at Laboratoire Aim£ Cotton under Pierre Jacquinot's leadership, over the

Compte rendu des Fick pics sous les étoiles (Pierre-André Doucet)