503 research outputs found

    KK-anonymous Signaling Scheme

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    We incorporate signaling scheme into Ad Auction setting, to achieve better welfare and revenue while protect users' privacy. We propose a new \emph{KK-anonymous signaling scheme setting}, prove the hardness of the corresponding welfare/revenue maximization problem, and finally propose the algorithms to approximate the optimal revenue or welfare

    A study of dynamical processes in the Orion KL region using ALMA-- Probing molecular outflow and inflow

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    This work reports a high spatial resolution observations toward Orion KL region with high critical density lines of CH3_{3}CN (124_{4}-114_{4}) and CH3_{3}OH (8βˆ’1,8_{-1, 8}-70,7_{0, 7}) as well as continuum at ∼\sim1.3 mm band. The observations were made using the Atacama Large Millimeter/Submillimeter Array with a spatial resolution of ∼\sim1.5β€²β€²^{\prime\prime} and sensitives about 0.07 K and ∼\sim0.18 K for continuum and line, respectively. The observational results showed that the gas in the Orion KL region consists of jet-propelled cores at the ridge and dense cores at east and south of the region, shaped like a wedge ring. The outflow has multiple lobes, which may originate from an explosive ejection and is not driven by young stellar objects. Four infrared bubbles were found in the Spitzer/IRAC emissions. These bubbles, the distributions of the previously found H2_2 jets, the young stellar objects and molecular gas suggested that BN is the explosive center. The burst time was estimated to be ≀\leq 1300 years. In the mean time, signatures of gravitational collapse toward Source I and hot core were detected with material infall velocities of 1.5 km~sβˆ’1^{-1} and ∼\sim 0.6 km~sβˆ’1^{-1}, corresponding to mass accretion rates of 1.2Γ—\times10βˆ’3^{-3}M_{\sun}/Yr and 8.0Γ—\times10βˆ’5^{-5}M_{\sun}/Yr, respectively. These observations may support that high-mass stars form via accretion model, like their low-mass counterparts.Comment: Accepted to Ap
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