65,172 research outputs found
A decision model applied to alcohol effects on driver signal light behavior
A decision model including perceptual noise or inconsistency is developed from expected value theory to explain driver stop and go decisions at signaled intersections. The model is applied to behavior in a car simulation and instrumented vehicle. Objective and subjective changes in driver decision making were measured with changes in blood alcohol concentration (BAC). Treatment levels averaged 0.00, 0.10 and 0.14 BAC for a total of 26 male subjects. Data were taken for drivers approaching signal lights at three timing configurations. The correlation between model predictions and behavior was highly significant. In contrast to previous research, analysis indicates that increased BAC results in increased perceptual inconsistency, which is the primary cause of increased risk taking at low probability of success signal lights
Method and apparatus for aligning a laser beam projector Patent
Laser beam projector for continuous, precise alignment between target, laser generator, and astronomical telescope during trackin
Method of directing a laser beam with very high accuracy
System will collimate and direct an argon laser beam with high angular tracking accuracy at objects on the moons surface. It can be adapted to missile and satellite tracking
Remote Detection of Saline Intrusion in a Coastal Aquifer Using Borehole Measurements of Self-Potential
Funded by NERC CASE studentship . Grant Number: NE/I018417/1Peer reviewedPublisher PD
NVU dynamics. III. Simulating molecules at constant potential energy
This is the final paper in a series that introduces geodesic molecular
dynamics at constant potential energy. This dynamics is entitled NVU dynamics
in analogy to standard energy-conserving Newtonian NVE dynamics. In the first
two papers [Ingebrigtsen et al., J. Chem. Phys. 135, 104101 (2011); ibid,
104102 (2011)], a numerical algorithm for simulating geodesic motion of atomic
systems was developed and tested against standard algorithms. The conclusion
was that the NVU algorithm has the same desirable properties as the Verlet
algorithm for Newtonian NVE dynamics, i.e., it is time-reversible and
symplectic. Additionally, it was concluded that NVU dynamics becomes equivalent
to NVE dynamics in the thermodynamic limit. In this paper, the NVU algorithm
for atomic systems is extended to be able to simulate geodesic motion of
molecules at constant potential energy. We derive an algorithm for simulating
rigid bonds and test this algorithm on three different systems: an asymmetric
dumbbell model, Lewis-Wahnstrom OTP, and rigid SPC/E water. The rigid bonds
introduce additional constraints beyond that of constant potential energy for
atomic systems. The rigid-bond NVU algorithm conserves potential energy, bond
lengths, and step length for indefinitely long runs. The quantities probed in
simulations give results identical to those of Nose-Hoover NVT dynamics. Since
Nose-Hoover NVT dynamics is known to give results equivalent to those of NVE
dynamics, the latter results show that NVU dynamics becomes equivalent to NVE
dynamics in the thermodynamic limit also for molecular systems.Comment: 14 pages, 12 figure
Development of optical data processing techniques applicable to detection and study of meteor trails
Development of coherent optical data processing techniques applicable to detection of meteor trails and examination of propertie
Thermal decomposition of a honeycomb-network sheet - A Molecular Dynamics simulation study
The thermal degradation of a graphene-like two-dimensional triangular
membrane with bonds undergoing temperature-induced scission is studied by means
of Molecular Dynamics simulation using Langevin thermostat. We demonstrate that
the probability distribution of breaking bonds is highly peaked at the rim of
the membrane sheet at lower temperature whereas at higher temperature bonds
break at random anywhere in the hexagonal flake. The mean breakage time
is found to decrease with the total number of network nodes by a power law
and reveals an Arrhenian dependence on temperature .
Scission times are themselves exponentially distributed. The fragmentation
kinetics of the average number of clusters can be described by first-order
chemical reactions between network nodes of different coordination. The
distribution of fragments sizes evolves with time elapsed from a
-function through a bimodal one into a single-peaked again at late
times. Our simulation results are complemented by a set of -order
kinetic differential equations for which can be solved exactly and
compared to data derived from the computer experiment, providing deeper insight
into the thermolysis mechanism.Comment: 21pages, 9 figures, LaTeX, revised versio
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