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What situations trigger intense emotions in automobiles?
Conference ProceedingsDriving involves a variety of events and activities that stimulate emotional experiences. The aim of this investigation was to examine automobile experiences and to identify affective themes. 245 UK-based participants were recruited using a
purposive sampling strategy. One study consisted of an online questionnaire which inquired about the automotive experiences which proved most emotionally intense. The second consisted of a simulator based immersive driving experience, followed
afterwards by a questionnaire which inquired about the automotive experiences which proved most emotionally intense. Questionnaire responses were clustered into themes using a content analysis method. The study identified 13 major themes and 44 sub-themes. The findings provide guidance regarding the triggers of emotional responses which designers can use to better understand and to improve automotive experiences.Jaguar Land Rover as part of project Automotive Habitat Laboratory (AutoHablab)
Phase Transitions in the Two-Dimensional XY Model with Random Phases: a Monte Carlo Study
We study the two-dimensional XY model with quenched random phases by Monte
Carlo simulation and finite-size scaling analysis. We determine the phase
diagram of the model and study its critical behavior as a function of disorder
and temperature. If the strength of the randomness is less than a critical
value, , the system has a Kosterlitz-Thouless (KT) phase transition
from the paramagnetic phase to a state with quasi-long-range order. Our data
suggest that the latter exists down to T=0 in contradiction with theories that
predict the appearance of a low-temperature reentrant phase. At the critical
disorder and for there is no
quasi-ordered phase. At zero temperature there is a phase transition between
two different glassy states at . The functional dependence of the
correlation length on suggests that this transition corresponds to the
disorder-driven unbinding of vortex pairs.Comment: LaTex file and 18 figure
Phase diagram of a Disordered Boson Hubbard Model in Two Dimensions
We study the zero-temperature phase transition of a two-dimensional
disordered boson Hubbard model. The phase diagram of this model is constructed
in terms of the disorder strength and the chemical potential. Via quantum Monte
Carlo simulations, we find a multicritical line separating the weak-disorder
regime, where a random potential is irrelevant, from the strong-disorder
regime. In the weak-disorder regime, the Mott-insulator-to-superfluid
transition occurs, while, in the strong-disorder regime, the
Bose-glass-to-superfluid transition occurs. On the multicritical line, the
insulator-to-superfluid transition has the dynamical critical exponent and the correlation length critical exponent ,
that are different from the values for the transitions off the line. We suggest
that the proliferation of the particle-hole pairs screens out the weak disorder
effects.Comment: 4 pages, 4 figures, to be published in PR
Rapid Surface Oxidation as a Source of Surface Degradation Factor for Bi2Se3
Bi2Se3 is a topological insulator with metallic surface states residing in a
large bulk bandgap. It is believed that Bi2Se3 gets additional n-type doping
after exposure to atmosphere, thereby reducing the relative contribution of
surface states in total conductivity. In this letter, transport measurements on
Bi2Se3 nanoribbons provide additional evidence of such environmental doping
process. Systematic surface composition analyses by X-ray photoelectron
spectroscopy reveal fast formation and continuous growth of native oxide on
Bi2Se3 under ambient conditions. In addition to n-type doping at the surface,
such surface oxidation is likely the material origin of the degradation of
topological surface states. Appropriate surface passivation or encapsulation
may be required to probe topological surface states of Bi2Se3 by transport
measurements
Thickness-Magnetic Field Phase Diagram at the Superconductor-Insulator Transition in 2D
The superconductor-insulator transition in ultrathin films of amorphous Bi
was tuned by changing the film thickness, with and without an applied magnetic
field. The first experimentally obtained phase diagram is mapped as a function
of thickness and magnetic field in the T=0 limit. A finite size scaling
analysis has been carried out to determine the critical exponent product vz,
which was found to be 1.2 for the zero field transition, and 1.4 for the finite
field transition. Both results are different from the exponents found for the
magnetic field tuned transition in the same system, 0.7.Comment: 4 pages, 4 figure
The Field-Tuned Superconductor-Insulator Transition with and without Current Bias
The magnetic-field-tuned superconductor-insulator transition has been studied
in ultrathin Beryllium films quench-condensed near 20 K. In the zero-current
limit, a finite-size scaling analysis yields the scaling exponent product vz =
1.35 +/- 0.10 and a critical sheet resistance R_{c} of about 1.2R_{Q}, with
R_{Q} = h/4e^{2}. However, in the presence of dc bias currents that are smaller
than the zero-field critical currents, vz becomes 0.75 +/- 0.10. This new set
of exponents suggests that the field-tuned transitions with and without dc bias
currents belong to different universality classes.Comment: RevTex 4 pages, 4 figures, and 1 table minor change
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