96,028 research outputs found
Charm semileptonic decays at LHCb
In these proceedings, we explore the possible reach of the LHCb dataset in
the area of charm semileptonic decays. Specifically, we give prospects for the
measurement of using with Run I data.
Preliminary projections show that the LHCb Run I dataset would give a relative
statistical uncertainty of on this ratio. We also motivate the
search for lepton non-universality in the charm sector.Comment: Proceedings of the 9th International Workshop on the CKM Unitarity
Triangle, 28 November - 3 December 2016, Tata Institute for Fundamental
Research (TIFR), Mumbai, India. 6 pages, 3 figure
Cosmic Strings, Zero Modes and SUSY breaking in Nonabelian N=1 Gauge Theories
We investigate the microphysics of cosmic strings in Nonabelian gauge
theories with N=1 supersymmetry. We give the vortex solutions in a specific
example and demonstrate that fermionic superconductivity arises because of the
couplings and interactions dictated by supersymmetry. We then use supersymmetry
transformations to obtain the relevant fermionic zero modes and investigate the
role of soft supersymmetry breaking on the existence and properties of the
superconducting strings.Comment: 12 pages, RevTex, submitted to Phys. Rev.
Configurations of Handles and the Classification of Divergences in the String Partition Function
The divergences that arise in the regularized partition function for closed
bosonic string theory in flat space lead to three types of perturbation series
expansions, distinguished by their genus dependence. This classification of
infinities can be traced to geometrical characteristics of the string
worldsheet. Some categories of divergences may be eliminated in string theories
formulated on compact manifolds.Comment: 24 pages, DAMTP-R/94/1
Exploring The Value Of Folksonomies For Creating Semantic Metadata
Finding good keywords to describe resources is an on-going problem: typically we select such words manually from a thesaurus of terms, or they are created using automatic keyword extraction techniques. Folksonomies are an increasingly well populated source of unstructured tags describing web resources. This paper explores the value of the folksonomy tags as potential source of keyword metadata by examining the relationship between folksonomies, community produced annotations, and keywords extracted by machines. The experiment has been carried-out in two ways: subjectively, by asking two human indexers to evaluate the quality of the generated keywords from both systems; and automatically, by measuring the percentage of overlap between the folksonomy set and machine generated keywords set. The results of this experiment show that the folksonomy tags agree more closely with the human generated keywords than those automatically generated. The results also showed that the trained indexers preferred the semantics of folksonomy tags compared to keywords extracted automatically. These results can be considered as evidence for the strong relationship of folksonomies to the human indexer’s mindset, demonstrating that folksonomies used in the del.icio.us bookmarking service are a potential source for generating semantic metadata to annotate web resources
An evaluation of auroral all-sky camera observations
From photometric, all-sky camera, and visual observations
of a moderate auroral display, it is found that the
all-sky camera compares favorably with the visual observer
in detecting and recording auroral forms. The visual
observer can make instantaneous observations and so can
detect rapid changes and auroral forms lasting only a few
seconds, whereas the poorer time resolution of the all-sky
camera prevents it from recording very short-lived phenonema.
However, the ability of the all-sky camera to accurately
record the shape and intensity of the majority of auroral
forms allows it to yield more precise and complete information
about these aspects of auroral morphology than is
normally obtained through visual observation.Ye
User's manual for MacPASCO
A user's manual is presented for MacPASCO, which is an interactive, graphic, preprocessor for panel design. MacPASCO creates input for PASCO, an existing computer code for structural analysis and sizing of longitudinally stiffened composite panels. MacPASCO provides a graphical user interface which simplifies the specification of panel geometry and reduces user input errors. The user draws the initial structural geometry and reduces user input errors. The user draws the initial structural geometry on the computer screen, then uses a combination of graphic and text inputs to: refine the structural geometry; specify information required for analysis such as panel load and boundary conditions; and define design variables and constraints for minimum mass optimization. Only the use of MacPASCO is described, since the use of PASCO has been documented elsewhere
Incorporating general race and housing flexibility and deadband in rolling element bearing analysis
Methods for including the effects of general race and housing compliance and outer race-to-housing deadband (clearance) in rolling element bearing mechanics analysis is presented. It is shown that these effects can cause significant changes in bearing stiffness characteristics, which are of major importance in rotordynamic response of turbomachinery and other rotating systems. Preloading analysis is demonstrated with the finite element/contact mechanics hybrid method applied to a 45 mm angular contact ball bearing
Preservation of flavor in freeze dried green beans
Before freeze drying, green beans are heated to point at which their cell structure is altered. Beans freeze dried with altered cell structure have improved rehydration properties and retain color, flavor, and texture
CMB Anisotropies in the Presence of Extra Dimensions
We discuss the effect of the time evolution of extra dimensions on CMB
anisotropies and large-scale structure formation. We study the impact of scalar
fields in a low-energy effective description of a general class of brane world
models on the temperature anisotropy power spectrum. We show that when the
coupling between these scalar fields and matter evolves over cosmological
timescales, current observations of the CMB anisotropies can constrain
primordial values of the fields in a manner complementary to local, late-time
tests of gravity. We also present the effect of these fields on the
polarization anisotropy spectra and the growth of large-scale structure,
showing that future CMB observations will constrain theories of the Universe
involving extra dimensions even further.Comment: 17 pages, 15 figure
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