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potential biological control agent for spider mites (Acari:

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Performance evaluation of computer networks is primarily done using packet-level simulation because analytical methods typically cannot adequately capture the combination of state-dependent control mechanisms (such as TCP congestion control) and stochastic behavior exhibited by networks. However, packet-level simulation becomes prohibitively expensive as link speeds, workloads, and net-work size increase. Timestepped Stochastic Simulation (TSS) is a novel technique that overcomes the scalability problems of packet-level simulation by generating a sample path of the system state S(t) at time t = ; 2; , rather than at each packet transmission. In each timestep [t; t+], the distribution Pr ( S(t+) jS(t)) is obtained analytically, and S(t + ) is sampled from it. This dissertation presents TSS for shared links, specically, 802.11 WLAN links. Our method computes sample paths of instantaneous goodput (successful transmissions per timestep) Ni(t) for all stations i in a WLAN over timesteps of length . For accurate modeling of higher layer protocols, should be lesser than their control timescales (e.g., TCP's round-trip time). At typical values of (e.g, 50ms), Ni(t)'s are correlated across timesteps (e.g., a station with high contention window has low goodput for several timesteps) as well as across stations (since they share the same media). To model these correlations, we obtain, jointly with the Ni(t)'s, sample paths of the WLAN's state, which consists of a contention window and a backo counter at each station. Comparisons with packet level simulations show that TSS is accurate and provides up to two orders of magnitude improvement in simulation runtime.

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Management support and early warning system for national biodiversity databases in a network of national, regional (EAAP) and international

This study explores the extent to which early childhood understanding of conception and birth is increased by early sexuality education. The present study compares conception and birth understanding of primary-aged children in America with children in other countries. Specifically, this study compared prompted drawings done

High strain electrostrictive polymers: elaboration methods and modelization

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