25,600 research outputs found
Neutrino masses in lepton number violating mSUGRA
In SUSY models which violate R-parity, there exist trilinear lepton number
violating (LNV) operators which can lead to neutrino masses. If these operators
are defined at the unification scale, the renormalization group flow becomes
important and generally leads to one neutrino mass much heavier than the
others. We study, in a minimal supergravity (mSUGRA) set-up with two trilinear
LNV operators and three charged lepton mixing angles, numerically how these
parameters may be arranged to be compatible with neutrino oscillation data, and
discuss some phenomenological observations.Comment: 3 pages, 2 figures. Talk given at SUSY08. To be published in the
Conference Proceeding
Enhancement of low-mass dileptons in SPS heavy-ion collisions: possible evidence for dropping rho meson mass in medium
Dilepton production in proton- and nucleus-induced reactions at SPS energies
is studied in the relativistic transport model using initial conditions
determined by the string dynamics from RQMD. It is found that both the CERES
and HELIOS-3 data for dilepton spectra in proton-nucleus reactions can be well
described by the conventional mechanism of Dalitz decay and direct vector meson
decay. However, to provide a quantitative explanation of the observed dilepton
spectra in central S+Au and S+W collisions requires contributions other than
these direct decays. Introducing a decrease of vector meson masses in hot dense
medium, we find that these heavy-ion data can also be satisfactorily explained.
We also give predictions for Pb+Au collisions at 160 GeV/nucleon using current
CERES mass resolution and acceptance.Comment: 8 pages, LaTeX, figures available from [email protected],
contribution to QM'96, to appear in the proceeding
Practical theories for service life prediction of critical aerospace structural components
A new second-order theory was developed for predicting the service lives of aerospace structural components. The predictions based on this new theory were compared with those based on the Ko first-order theory and the classical theory of service life predictions. The new theory gives very accurate service life predictions. An equivalent constant-amplitude stress cycle method was proposed for representing the random load spectrum for crack growth calculations. This method predicts the most conservative service life. The proposed use of minimum detectable crack size, instead of proof load established crack size as an initial crack size for crack growth calculations, could give a more realistic service life
Measurement Invariance of the Internet Addiction Test Among Hong Kong, Japanese, and Malaysian Adolescents
There has been increased research examining the psychometric properties on the Internet Addiction Test across different ages and populations. This population-based study examined the psychometric properties using Confirmatory Factory Analysis and measurement invariance using Item Response Theory (IRT) of the IAT in adolescents from three Asian countries. In the Asian Adolescent Risk Behavior Survey (AARBS), 2,535 secondary school students (55.91% girls) in Grade 7 to Grade 13 (Mean age = 15.61 years; SD=1.56) from Hong Kong (n=844), Japan (n=744), and Malaysia (n=947) completed a survey on their Internet use that incorporated the IAT scale. A nested hierarchy of hypotheses concerning IAT cross-country invariance was tested using multi-group confirmatory factor analysis. Replicating past finding in Hong Kong adolescents, the construct of IAT is best represented by a second-order three-factor structure in Malaysian and Japanese adolescents. Configural, metric, scalar, and partial strict factorial invariance was established across the three samples. No cross-country differences on Internet addiction were detected at latent mean level. This study provided empirical support to the IAT as a reliable and factorially stable instrument, and valid to be used across Asian adolescent populations
Studying Diquark Structure of Heavy Baryons in Relativistic Heavy Ion Collisions
We propose the enhancement of yield in heavy ion collisions at
RHIC and LHC as a novel signal for the existence of diquarks in the strongly
coupled quark-gluon plasma produced in these collisions as well as in the
. Assuming that stable bound diquarks can exist in the quark-gluon
plasma, we argue that the yield of would be increased by two-body
collisions between diquarks and quarks, in addition to normal
three-body collisions among , and quarks. A quantitative study of
this effect based on the coalescence model shows that including the
contribution of diquarks to production indeed leads to a
substantial enhancement of the ratio in heavy ion collisions.Comment: Prepared for Chiral Symmetry in Hadron and Nuclear Physics
(Chiral07), Nov. 13-16, 2007, Osaka, Japa
Development of High-Yielding and Early-Maturing Korean Hairy Vetch
There are a number of forage cultivars recommended by the government, but only a few winter-spring legumes are available for the farmers in Korea. Hairy vetch has superior winter hardiness and produces high dry matter (DM) yield compared with crimson clover, Persian clover, rose clover, common vetch and Chinese milk vetch in Korea. However, under a double cropping forage production system an early maturing vetch cultivar was more productive than a late maturing one (Shin et al., 2000). The objective of this research was to develop a high yielding and early flowering new hairy vetch cultivar derived from an accession in Korea
A Study of the Application of Design By Metaphors to the User Interface of Smartphones
The purpose of this study is to integrate user experiences, semiology, and the design by metaphors into user interfaces by experiments. Designs by metaphors are effectively integrated into the user interface of photo retouching apps on smartphones. Problems with the usage of the original interface can be resolved and the quality of product design can be improved. Current photo retouching apps usually come with a complicated user interface that makes users difficult to figure out a straightforward way of using the apps. Users might have less confidence in using the apps and their willingness of using is greatly reduced. The emerging trend of design by metaphors in recent years has resolved the issues that complicate user perception. It also helps designers simplify complicated user interfaces due to the requirement of multiple functions. An effective approach is proposed in this study to help designers create new user interfaces for photo retouching apps by using signs to simplify operation instructions. The resulting visual designs allow users to associate operations with something they are familiar with so that they can comprehend product functions in an effective way. The resulting design is clear at a glance so that users no longer make unintended uses. Moreover, the experiments in study opened a new horizon for the application of design by metaphors to user interfaces. This approach makes designers value product semantics more. As a result, people can enjoy their life in a more convenient and comfortable way.
Keywords: photo retouching app for smartphones, design by metaphors, operational semantics, semiology, user experienc
Cross sections for pentaquark baryon production from protons in reactions induced by hadrons and photons
Using hadronic Lagrangians that include the interaction of pentaquark
baryon with and , we evaluate the cross sections for its
production from meson-proton, proton-proton, and photon-proton reactions near
threshold. With empirical coupling constants and form factors, the predicted
cross sections are about 1.5 mb in kaon-proton reactions, 0.1 mb in rho-nucleon
reactions, 0.05 mb in pion-nucleon reactions, 20 b in proton-proton
reactions, and 40 nb in photon-proton reactions.Comment: 14 pages, 7 figure
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