3,762 research outputs found
Olfoto: designing a smell-based interaction
We present a study into the use of smell for searching digi-tal photo collections. Many people now have large photo libraries on their computers and effective search tools are needed. Smell has a strong link to memory and emotion so may be a good way to cue recall when searching. Our study compared text and smell based tagging. For the first stage we generated a set of smell and tag names from user de-scriptions of photos, participants then used these to tag pho-tos, returning two weeks later to answer questions on their photos. Results showed that participants could tag effec-tively with text labels, as this is a common and familiar task. Performance with smells was lower but participants performed significantly above chance, with some partici-pants using smells well. This suggests that smell has poten-tial. Results also showed that some smells were consistently identified and useful, but some were not and highlighted issues with smell delivery devices. We also discuss some practical issues of using smell for interaction
KINEMATIC COMPARATIVE ANALYSIS OF THE COORDINATION PATTERN OF THE BASKETBALL FREE THROW
Coordination patterns are an important part of everyday movement. The pattern of intersegmental movement is specific to each task we perform. Hudson (1986) broke down tasks into two basic categories: simultaneous which is used when accuracy is important to the task, and sequential which is used when velocity is the key to the task. The sequential pattern of movement is best defined by the summation of speed principle put forth by Bunn (1972) when he stated that in activities where the highest speed at the moment of release was necessary, the speed was developed when the movement of each segment started at the moment of greatest velocity of the preceding segment. The purpose of this study was to conduct a comparative biomechanical analysis of the system of coordination used in the basketball free throw. Four individuals of different abilities ranging from elite (a professional basketball player) to novice (an eleven year old boy with little basketball experience) participated in this study. The subjects were video taped (60 fps) shooting a free throw on a regulation basketball court in the sagittal plane on the right side (all subjects were right handed). Each performance was digitized and analyzed using the PEAK Performance 2-dimensional movement analysis system interfaced with a Panasonic AG-7350 recorder, Sony PVM-1341 monitor, and Zenith 486 microcomputer. The angular velocity of the shoulder, elbow, and wrist of the shooting arm and the hip, knee, and ankle of the same side were examined. It was found that all subjects exhibited simultaneous movement of all three joints of the leg. The elite performer exhibited sequential movement of the segments of the shooting arm where the novice exhibited complete simultaneous movement. From the results of the study, the free throw was defined as an intermediate task requiring both velocity and accuracy. This research may be used as a coaching tool in improving the performance of the free throw for any basketball player by studying the detailed analysis of the pattern of coordination of a professional player then comparing the player to any subject on the continuum outlined in this study
Weak antilocalization in a strained InGaAs/InP quantum well structure
Weak antilocalization (WAL) effect due to the interference corrections to the
conductivity has been studied experimentally in a strained InGaAs/InP quantum
well structure. From measurements in tilted magnetic filed, it was shown that
both weak localization and WAL features depend only on the normal component of
the magnetic field for tilt angles less than 84 degrees. Weak antilocalization
effect showed non-monotonous dependence on the gate voltage which could not be
explained by either Rashba or Dresselhouse mechanisms of the spin-orbit
coupling. To describe magnetic field dependence of the conductivity, it was
necessary to assume that spin-orbit scattering time depends on the external
magnetic field which quenches the spin precession around effective, spin-orbit
related, magnetic fields.Comment: Presented at EP2DS 2003 (Nara), to be published in Physica
EVAPORATION OF QUARK DROPS DURING THE COSMOLOGICAL Q-H TRANSITION
We have carried out a study of the hydrodynamics of disconnected quark
regions during the final stages of the cosmological quark-hadron transition. A
set of relativistic Lagrangian equations is presented for following the
evaporation of a single quark drop and results from the numerical solution of
this are discussed. A self-similar solution is shown to exist and the formation
of baryon number density inhomogeneities at the end of the drop contraction is
discussed.Comment: 12 pages Phys. Rev. format, uuencoded postscript file including 12
figure
System modelling for Rankine Cycle waste heat recovery from a spark ignition engine
Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.The Rankine Cycle can be used to convert low grade heat, including the dual heat sources of a spark ignition engine, into useful energy. To maximise the shaft power output, by optimising the capture of waste heat, requires detailed consideration of the cycle thermodynamics. A spreadsheet model for each proposed Rankine Cycle configuration has been developed and the results verified by comparison with a standard industry process engineering software package. The spreadsheet model results may be more reliable because the thermodynamic data are based on real data rather than equations of state. Comparisons of the proposed cycles are given for hexane as the working fluid.cs201
Charge-Symmetry Breaking and the Two-Pion-Exchange Two-Nucleon Interaction
Charge-symmetry breaking in the nucleon-nucleon force is investigated within
an effective field theory, using a classification of isospin-violating
interactions based on power-counting arguments. The relevant
charge-symmetry-breaking interactions corresponding to the first two orders in
the power counting are discussed, including their effects on the 3He-3H
binding-energy difference. The static charge-symmetry-breaking potential linear
in the nucleon-mass difference is constructed using chiral perturbation theory.
Explicit formulae in momentum and configuration spaces are presented. The
present work completes previously obtained results.Comment: 15 pages, 2 figure
Firearm access and adolescent suicide risk: Toward a clearer understanding of effect size
Background: Strong and consistent associations between access to firearms and suicide have been found in ecologic and individual-level observational studies. For adolescents, a seminal case-control study estimated that living in a home with (vs without) a firearm was associated with a fourfold increase in the risk of death by suicide. Methods: We use data from a nationally representative study of 10 123 US adolescents aged 13-18 years to (1) measure how much adolescents who live in a home with a firearm differ from those who do not in ways related to their risk of suicide, and (2) incorporate these differences into an updated effect estimate of the risk of adolescent suicide attributable to living in a home with firearms. Results: Almost one-third (30.7%) of adolescents reported living in a home with firearms. Relative to those who did not, adolescents reporting living in a home with a firearm were slightly more likely to be male, older and reside in the South and rural areas, but few differences were identified for mental health characteristics. The effect size found by Brent and colleagues appeared robust to sources of possible residual confounding: updated relative risks remained above 4.0 across most sensitivity analyses and at least 3.1 in even the most conservative estimates. Conclusions: Although unmeasured confounding and other biases may nonetheless remain, our updated estimates reinforce the suggestion that adolescents' risk of suicide was increased threefold to fourfold if they had lived in homes with a firearm compared with if they had not
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