4,908 research outputs found
Could be a molecular state?
We investigate whether the newly observed narrow resonance can
be described as a molecular state with quantum numbers
. Using QCD sum rules, we consider contributions up to dimension
six in the operator product expansion and work at leading order of
. The mass obtained for this state is (4.05\pm 0.28) \mbox{GeV}.
It is concluded that molecular state is a possible candidate
for .Comment: 7 pages, 4 figures.Published in Eur.Phys.J. C73 (2013) 2661. arXiv
admin note: text overlap with arXiv:1304.185
Higher order light-cone distribution amplitudes of the Lambda baryon
The improved light-cone distribution amplitudes (LCDAs) of the
baryon are examined on the basis of the QCD conformal partial wave expansion
approach. The calculations are carried out to the next-to-leading order of
conformal spin accuracy with consideration of twist 6. The next leading order
conformal expansion coefficients are related to the nonperturbative parameters
defined by the local three quark operator matrix elements with different
Lorentz structures with a covariant derivative. The nonperturbative parameters
are determined with the QCD sum rule method. The explicit expressions of the
LCDAs are provided as the main results.Comment: 17pages,10figures. arXiv admin note: text overlap with
arXiv:1311.596
A new and efficient intelligent collaboration scheme for fashion design
Technology-mediated collaboration process has been extensively studied for over a decade. Most applications with collaboration concepts reported in the literature focus on enhancing efficiency and effectiveness of the decision-making processes in objective and well-structured workflows. However, relatively few previous studies have investigated the applications of collaboration schemes to problems with subjective and unstructured nature. In this paper, we explore a new intelligent collaboration scheme for fashion design which, by nature, relies heavily on human judgment and creativity. Techniques such as multicriteria decision making, fuzzy logic, and artificial neural network (ANN) models are employed. Industrial data sets are used for the analysis. Our experimental results suggest that the proposed scheme exhibits significant improvement over the traditional method in terms of the time–cost effectiveness, and a company interview with design professionals has confirmed its effectiveness and significance
IC-integrated flexible shear-stress sensor skin
This paper reports the successful development of the first IC-integrated flexible MEMS shear-stress sensor skin. The sensor skin is 1 cm wide, 2 cm long, and 70 /spl mu/m thick. It contains 16 shear-stress sensors, which are arranged in a 1-D array, with on-skin sensor bias, signal-conditioning, and multiplexing circuitry. We further demonstrated the application of the sensor skin by packaging it on a semicylindrical aluminum block and testing it in a subsonic wind tunnel. In our experiment, the sensor skin has successfully identified both the leading-edge flow separation and stagnation points with the on-skin circuitry. The integration of IC with MEMS sensor skin has significantly simplified implementation procedures and improved system reliability
A parametrized three-dimensional model for MEMS thermal shear-stress sensors
This paper presents an accurate and efficient model of MEMS thermal shear-stress sensors featuring a thin-film hotwire on a vacuum-isolated dielectric diaphragm. We consider three-dimensional (3-D) heat transfer in sensors operating in constant-temperature mode, and describe sensor response with a functional relationship between dimensionless forms of hotwire power and shear stress. This relationship is parametrized by the diaphragm aspect ratio and two additional dimensionless parameters that represent heat conduction in the hotwire and diaphragm. Closed-form correlations are obtained to represent this relationship, yielding a MEMS sensor model that is highly efficient while retaining the accuracy of three-dimensional heat transfer analysis. The model is compared with experimental data, and the agreement in the total and net hotwire power, the latter being a small second-order quantity induced by the applied shear stress, is respectively within 0.5% and 11% when uncertainties in sensor geometry and material properties are taken into account. The model is then used to elucidate thermal boundary layer characteristics for MEMS sensors, and in particular, quantitatively show that the relatively thick thermal boundary layer renders classical shear-stress sensor theory invalid for MEMS sensors operating in air. The model is also used to systematically study the effects of geometry and material properties on MEMS sensor behavior, yielding insights useful as practical design guidelines
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