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Cambron G.K. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1992,80(4):628-636
The author examines the deployment of Signaling System No.7 (SS7) from the viewpoint of the local exchange carrier. The three phases of local exchange deployment-service planning and design, local exchange network design, and interconnection design-are discussed in sequence. SS7 is a fundamental change to the infrastructure of the local exchange telecommunications network. The author describes how the backbone network, centered on the signaling transfer points (STPs), is installed first, followed by the local exchange network, and then interconnection to interchange and other networks 相似文献
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Scott M. Berry Thomas J. Roussel Scott D. Cambron Robert W. Cohn Robert S. Keynton 《Microfluidics and nanofluidics》2012,13(3):451-459
Freely suspended microchannels with diameters ranging from 4 to 100?μm were fabricated by utilizing directly written PMMA fibers as sacrificial structures. These precisely oriented fibers served as scaffolds around which thin cylinders of glass were deposited (via sputtering), followed by a conformal coating of Parylene to augment the mechanical integrity of the structures. After coating, the PMMA fibers were dissolved to yield suspended, hollow conduits that were hydrophilic and robust. The freely suspended channels were loaded with a buffer solution containing charged particles, which were subsequently electrokinetically manipulated and velocities quantified using microparticle image velocimetry (μPIV). Mobilities within 1.3?% of those observed in conventional, planar microchannels were recorded. 相似文献
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Martin N. Andersson Jenny Haftmann Jeffrey J. Stuart Sue E. Cambron Marion O. Harris Stephen P. Foster Stephan Franke Wittko Francke Ylva Hillbur 《Journal of chemical ecology》2009,35(1):81-95
Coupled gas chromatographic (GC)–electroantennographic detection (EAD) analyses of ovipositor extract of calling Hessian fly,
Mayetiola destructor, females revealed that seven compounds elicited responses from male antennae. Four of the compounds—(2S)-tridec-2-yl acetate, (2S,10Z)-10-tridecen-2-yl acetate, (2S,10E)-10-tridecen-2-yl acetate, and (2S,10E)-10-tridecen-2-ol—were identified previously in female extracts. Two new EAD-active compounds, (2S,8Z,10E)-8,10-tridecadien-2-yl acetate and (2S,8E,10E)-8,10-tridecadien-2-yl acetate, were identified by GC–mass spectroscopy (MS) and the use of synthetic reference samples.
In a Y-tube bioassay, a five-component blend (1 ng (2S)-tridec-2-yl acetate, 10 ng (2S,10E)-10-tridecen-2-yl acetate, 1 ng (2S,10E)-10-tridecen-2-ol, 1 ng (2S,8Z,10E)-8,10-tridecadien-2-yl acetate, and 1 ng (2S,8E,10E)-8,10-tridecadien-2-yl acetate) was as attractive to male Hessian flies as a similar amount of female extract (with respect
to the main compound, (2S,10E)-10-tridecen-2-yl acetate). The five-component blend was more attractive to male flies than a three-component blend lacking
the two dienes. Furthermore, the five-component blend was more attractive than a blend with the same compounds but that contained
one tenth the concentration of (2S,8E,10E)-8,10-tridecadien-2-yl acetate (more accurately mimicking the ratios found in female extract). This suggests that the ratios
emitted by females might deviate from those in gland extracts. In a field-trapping experiment, the five-component blend applied
to polyethylene cap dispensers in a 100:10 μg ratio between the main component and each of the other blend components attracted
a significant number of male Hessian flies. Also, a small-plot field test demonstrated the attractiveness of the five-component
blend to male Hessian flies and suggests that this pheromone blend may be useful for monitoring and predicting Hessian fly
outbreaks in agricultural systems. 相似文献
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Three methods for compensating multiple frequency acoustic admittance measurements for ear canal volume were studied in 26 men with normal middle ear transmission systems. Peak compensated static acoustic admittance (magnitude of y) and phase angle (phi) were calculated from sweep frequency tympanograms (226-1243 Hz in 113 Hz increments). Of the procedures used to compensate for volume in rectangular form, the ear canal pressure used to estimate volume had the largest effect on the estimate of middle ear resonance. Median resonance was 800 Hz for admittance measurements compensated at 200 daPa versus 1100 Hz for measurements compensated at -350 daPa. The remaining two methods, compensation of susceptance only versus both susceptance and conductance and compensation using the minimum volume versus separate volumes at each frequency, did not affect estimates of middle ear resonance. Estimates of middle ear resonance from compensated phase angle measurements also were compared with estimates of resonance from admittance and phase difference curves. Although resonance could not be estimated from the phase difference curve, resonance estimated from the admittance difference curve agreed with the estimate from compensated phase angle. 相似文献
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