30,128 research outputs found
Estimated Surface Motions of the Earth's Core
Estimated surface fluid motions of earth core, and rotational and irrotational flow dat
Comparison of estimates of surface fluid motions of the earth's core various epochs
Method of determining velocity of surface fluid motions of earth core for various epoch
Acoustic based safety emergency vehicle detection for intelligent transport systems
A system has been investigated for the detection of incoming direction of an emergency vehicle. Acoustic detection methods based on a cross microphone array have been implemented. It is shown that source detection based on time delay estimation outperforms sound intensity techniques, although both techniques perform well for the application. The relaying of information to the driver as a warning signal has been investigated through the use of ambisonic technology and a 4 speaker array which is ubiquitous in most modern vehicles. Simulations show that accurate warning information may be relayed to the driver and afford correct action
Nature of surface flow in the earth's central core
Nonuniform fluid velocity effect at surface of earth core on nature of surface flo
Variable frequency microwave (VFM) processing facilities and application in processing thermoplastic matrix composites
Microwave processing of materials is a relatively new technology advancement alternative that provides new approaches for enhancing material properties as well as economic advantages through energy savings and accelerated product development. Factors that hinder the use of microwaves in materials processing are declining, so that prospect for the development of this technology seem to be very promising. The two mechanisms of orientation polarisation and interfacial space charge polarisation, together with dc conductivity, form the basis of high frequency heating. Clearly, advantages in utilising microwave technologies for processing materials include penetration radiation, controlled electric field distribution and selective and volumetric heating. However, the most commonly used facilities for microwave processing materials are of fixed frequency, e.g. 2.45 GHz. This paper presents a state-of-the-art review of microwave technologies, processing methods and industrial applications, using variable frequency microwave (VFM) facilities. This is a new alternative for microwave processing
Analysis of B-> \phi K Decays in QCD Factorization
We analyze the decay within the framework of QCD-improved
factorization. We found that although the twist-3 kaon distribution amplitude
dominates the spectator interactions, it will suppress the decay rates
slightly. The weak annihilation diagrams induced by penguin
operators, which are formally power-suppressed by order , are
chirally and logarithmically enhanced. Therefore, these annihilation
contributions are not subject to helicity suppression and can be sizable. The
predicted branching ratio of is in
the absence of annihilation contributions and it becomes
when annihilation effects are taken into
account. The prediction is consistent with CLEO and BaBar data but smaller than
the BELLE result.Comment: 13 pages, 3 figures. A major change for the presentation of
branching-ratio predictions. Experimental data are update
A simple solution of sound transmission through an elastic wall to a rectangular enclosure, including wall damping and air viscosity effects
A simple solution to the problem of the acoustical coupling between a rectangular structure, its air content, and an external noise source is presented. This solution is a mathematical expression for the normalized acoustic pressure inside the structure. Numerical results for the sound-pressure response for a specified set of parameters are also presented
Hadronic Form Factors: Combining QCD Calculations with Analyticity
I discuss recent applications of QCD light-cone sum rules to various form
factors of pseudoscalar mesons. In this approach both soft and hard
contributions to the form factors are taken into account. Combining QCD
calculation with the analyticity of the form factors, one enlarges the region
of accessible momentum transfers.Comment: 12 pages, 3 figures, Talk at the Workshop "Shifmania, Crossing the
boundaries: Gauge dynamics at strong coupling", May 14-17,2009, Minneapolis,
USA; table entry and reference update
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