Collaborative Collective Algorithms to Coordinate UGVs

Sentel/Brilliant Innovations has developed autonomous UGVs (unmanned ground vehicles) capable of generating a map of an unknown location through exploration using local software and the power of Google Tango technology. This project was tasked with developing an efficient and capable map-stitching solution allowing multiple UGVs to coordinate their movements and share information in order to greatly improve the speed at which these drones can be used to generate maps. The solution utilizes the processing power of a Raspberry Pi to pull maps from a Redis server and stitch them together. Once stitched, the maps are redistributed via the Redis server back through the network, providing every UGV the opportunity to obtain the global map. All of this stitching is performed on a single UGV, freeing the other drones to focus on generating and uploading their own unique maps to the server. The drones can use this new information to better inform their next move to prevent multiple drones from generating a map of the same location. In the future, Sentel/Brilliant Innovations hopes to take this technology and attach more advanced sensors to the drones, allowing them to add greater detail of the environment to the map rather than simply drawing boundaries. These drones have many potential applications, such as search and rescue, seeking out potential hazards, and intelligence for military and civil use.https://scholarscompass.vcu.edu/capstone/1187/thumbnail.jp

The PHENIX Experiment at RHIC

The physics emphases of the PHENIX collaboration and the design and current status of the PHENIX detector are discussed. The plan of the collaboration for making the most effective use of the available luminosity in the first years of RHIC operation is also presented.Comment: 5 pages, 1 figure. Further details of the PHENIX physics program available at http://www.rhic.bnl.gov/phenix

Heavy flavor production in PHENIX

O. Drapier on behalf of the PHENIX Collaboration, EIThe PHENIX experiment at RHIC measured single electron spectra in p + p, d + Au and Au + Au collisions at $\sqrt{s_{NN}} = 200$ GeV, and in Au + Au collisions at $\sqrt{s_{NN}} = 62.4$ GeV. In these spectra, electrons from semi-leptonic decays of charmed particles are the dominant contribution after subtraction of all 'photonic' sources (photon conversions, Dalitz decays, decays of light vector mesons). The p + p open charm production cross-section is found to be in good agreement with pQCD NLO calculations. The shape of the distributions obtained for p + p interactions is compared with those observed for nucleus-nucleus collisions. From p + p to d + Au and Au + Au interactions, open charm production is found to scale with the number of binary collisions $N_{\rm coll}$ . Au + Au data at $\sqrt{s_{NN}} = 62.4$ GeV is compatible with the ISR p + p results scaled by $N_{\rm coll}$ . The elliptic flow parameter v2 of heavy flavor electrons has also been measured, and is found to be non-zero in the intermediate pT range

Medium effects on high ¶T\P_{T} particle production measured with the PHENIX experiment

EITransverse momentum $\P_{T}$ spectra measured by the PHENIX experiment at RHIC in Au + Au, d + Au and pp collisions at $\sqrt {^S{NN}} = 200 GeV$ and in Au + Au collisions at $\sqrt {^S{NN}} = 62.4 GeV$ are presented. A suppression of the yield of high $\P_{T}$ hadrons in central Au + Au collisions by a factor 4-5 at $\P_{T}>5$ is found relative to the pp reference scaled by the nuclear overlap function (\T_{AB}) . In contrast, direct photons are not suppressed in central Au + Au collisions and no suppression of high $\P_{T}$ particles can be seen in d + Au collisions. This leads to the conclusion that the dense medium formed in central Au + Au collisions is responsible for the suppression

Can ϕ\phi mesons give an answer to the baryon puzzle at RHIC?

EIInternational audienceThe PHENIX experiment at RHIC has observed a large enhancement of baryon and anti-baryon production at ~ 2-5 GeV/c, compared to expectations from jet fragmentation. While a number of theoretical interpretations of the data are available, there is not yet a definitive answer to the “baryon puzzle”. We investigate the centrality dependence of -meson production at mid-rapidity in Au + Au collisions with $sqrt {^{s}NN}=200 GeV$. Comparison with the proton and anti-proton spectra reveal similar shapes, as expected for soft production described by hydrodynamics. However, the absolute yields show a different centrality dependence. The nuclear modification factors for $\phi$ are similar to those of pions, rather than (anti)protons that have similar mass. At intermediate , baryon/meson effects seem to be more important than the mass effects, in support of recombination models