47,427 research outputs found
Ideologies and informality in urban infrastructure: the case of housing in Soviet and post-Soviet Baku
W Mass at LEP and Standard Model Fits
The W-mass measurements from LEP and the results of a global fit of the
Standard Model parameters to the electroweak data are presented. Comprehensive
studies of experimental systematic effects allowed a measurement of the W mass
with an accuracy of better than half a permill. Especially the recent
improvements in the LEP energy calibration, the modelling of the hadronisation
process and the understanding of Bose-Einstein correlations and colour
reconnection effects are discussed. The fit of the Standard Model parameters to
all electroweak measurements verifies the self-consistency of the theory. The
combination of all electroweak data yield information on the mass of the still
undiscovered Higgs boson, .Comment: Proceedings of the XLIst Recontres de Moriond, La Thuile, March 200
The scatter of mechanical values of carbon fiber composites and its causes
The scatter of experimental data obtained in an investigation of the parameters of structural components was investigated. Strength parameters which are determined by the resin or the adhesion between fiber and resin were included. The statistical characteristics of the mechanical parameters of carbon fiber composites, and the possibilities which exist to reduce this scatter were emphasized. It is found that quality control tests of fiber and resin are important for such a reduction
Binary hard-sphere fluids near a hard wall
By using the Rosenfeld density functional we determine the number density
profiles of both components of binary hard-sphere fluids close to a planar hard
wall as well as the corresponding excess coverage and surface tension. The
comparison with published simulation data demonstrates that the Rosenfeld
functional, both its original version and sophistications thereof, is superior
to previous approaches and exhibits the same excellent accuracy as known from
studies of the corresponding one-component system
Electroweak Radiative Corrections to Off-Shell W-Pair Production
We briefly describe the RacoonWW approach to calculate radiative corrections
to e+ e- -> W W -> 4 fermions and present numerical results for the total
W-pair production cross section at LEP2.Comment: 3 pages, 2 figures, talk given at the DPF2000 meeting, Columbus, OH,
August 9-12, 200
A Piecewise Linear State Variable Technique for Real Time Propulsion System Simulation
The emphasis on increased aircraft and propulsion control system integration and piloted simulation has created a need for higher fidelity real time dynamic propulsion models. A real time propulsion system modeling technique which satisfies this need and which provides the capabilities needed to evaluate propulsion system performance and aircraft system interaction on manned flight simulators was developed and demonstrated using flight simulator facilities at NASA Ames. A piecewise linear state variable technique is used. This technique provides the system accuracy, stability and transient response required for integrated aircraft and propulsion control system studies. The real time dynamic model includes the detail and flexibility required for the evaluation of critical control parameters and propulsion component limits over a limited flight envelope. The model contains approximately 7.0 K bytes of in-line computational code and 14.7 K of block data. It has an 8.9 ms cycle time on a Xerox Sigma 9 computer. A Pegasus-Harrier propulsion system was used as a baseline for developing the mathematical modeling and simulation technique. A hydromechanical and water injection control system was also simulated. The model was programmed for interfacing with a Harrier aircraft simulation at NASA Ames. Descriptions of the real time methodology and model capabilities are presented
Sympathetic cooling of He ions in a radiofrequency trap
We have generated Coulomb crystals of ultracold He ions in a linear
radiofrequency trap, by sympathetic cooling via laser--cooled Be.
Stable crystals containing up to 150 localized He ions at 20 mK were
obtained. Ensembles or single ultracold He ions open up interesting
perspectives for performing precision tests of QED and measurements of nuclear
radii. The present work also indicates the feasibility of cooling and
crystallizing highly charged atomic ions using Be as coolant.Comment: 4 pages, 2 figure
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