Roger Welser

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Effects of smoking multiple cigarettes on EEG, vigilance, and subjective state were assessed in a repeated measures design where noise level (high versus minimal) was crossed with nicotine dose (quasi-ad lib own versus 1.0 mg FTC nicotine machine-delivered dose versus 0.05 mg FTC nicotine machine-delivered dose). Vigilance was increased by nicotine, but not(More)
We report on investigations of the initial drift in DC current gain, or beta (b), during the early stages of reliability testing of MOCVD-grown carbon doped InGaP/GaAs HBTs. The b drift is compared for different HBT structures with varying burn-in percentages. Competing mechanisms are observed in which b can either increase or decrease during the initial(More)
We have demonstrated the DC characteristics and CDMA performance of an NpN InGaP/InGaAsN/GaAs double heterojunction bipolar transistor (DHBT) and compared the results to conventional InGaP/GaAs HBTs. A 100 mV reduction in base-emitter turn-on voltage and 35 mV reduction in offset voltage is established relative to InGaP/GaAs HBTs using a low energy-gap(More)
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