T. Dale Roberts

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The Capacity Assignment (CA) problem focuses on finding the best possible set of capacities for the links that satisfies the traffic requirements in a prioritized network while minimizing the cost. Most approaches consider a single class of packets flowing through the network, but in reality, different classes of packets with different packet lengths and(More)
We present a discretized learning automaton (LA) solution to the capacity assignment (CA) problem which focuses on finding the best possible set of capacities for the links that satisfy the traffic requirements in a prioritized network while minimizing the cost. Most approaches consider a single class of packets flowing through the network, but in reality,(More)
The Capacity Assignment (CA) problem focuses on finding the best possible set of capacities for the links that satisfies the traffic requirements in a prioritized network while minimizing the cost. Most approaches consider a single class of packets flowing through the network, but in reality, different classes of packets with different packet lengths and(More)
We demonstrate the absence of off-diagonal elements for the density matrix of a supersonic Na atomic beam, thus showing that there are no coherent wave packets emerging from this source. We used a differentially detuned separated oscillatory field longitudinal interferometer to search for off-diagonal density matrix elements in the longitudinal(More)
Localized oscillating fields are beam splitters that can entangle internal and longitudinal momentum states in an atomic beam. Differentially detuned separated oscillatory fields and an am modulator constitute a " white fringe " longitudinal interferometer which rephases velocity averaging by a process analogous to half a spin echo. Differentially detuned(More)
We have measured the index of refraction for sodium de Broglie waves in gases of Ar, Kr, Xe, and N2 over a wide range of sodium velocities. We observe glory oscillations--a velocity-dependent oscillation in the forward scattering amplitude. An atom interferometer was used to observe glory oscillations in the phase shift caused by the collision, which are(More)
A new technique for maintaining high contrast in an atom interferometer is used to measure large de Broglie wave phase shifts. Dependence of an interaction induced phase on the atoms' velocity is compensated by applying an engineered counterphase. The counterphase is equivalent to a rotation, is precisely determined by a frequency, and can be used to(More)
Overview We are pioneering new measurement techniques using coherent atom optics (such as beam-splitters, mirrors and lenses) to manipulate matter waves. We operate an atom interferometer, similar to a Mach-Zehnder optical interferometer, which splits deBroglie waves of matter into two physically separated paths. After an interaction region where each atom(More)
Overview We are pioneering new measurement techniques using coherent atom optics (such as beam-splitters, mirrors and lenses) to manipulate matter waves. We operate an atom interferometer, similar to a Mach-Zhender optical interferometer, which splits deBroglie waves of matter into two physically separated paths. After an interaction region where each atom(More)
During the past year, we finally succeeded in our search to observe Bose-Einstein condensation (BEC) in atomic hydrogen. The techniques for trapping and cooling hydrogen differ in many respects from those used to achieve BEC in alkali metal atoms, and we use a new tool for studying the con-densate: high-resolution two-photon spectroscopy. Bose-Einstein(More)