11,680 research outputs found
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Perception enhancement system for automotive steering
Laboratory-based experiments were conducted to
evaluate the effect of the frequency and scale of
transient vibration events on the human detection of
road surface type by means of steering wheel vibration.
The study used steering wheel tangential direction
acceleration time histories which had been measured in
a mid-sized European automobile that was driven over
three different types of road surface. The steering
acceleration stimuli were manipulated by means of the
mildly non-stationary mission synthesis (MNMS)
algorithm in order to produce test stimuli which were
selectively modified in terms of the number, and size, of
transient vibration events they contained. Fifteen test
participants were exposed to both unmanipulated and
manipulated steering wheel rotational vibration stimuli,
and were asked to indicate, by either “yes or no”,
whether the test stimuli was from a target road surface
which was displayed on a board. The findings suggested
that transient vibration events play a key role in the
human detection of road surface type in driving
situations. Improvements of up to 20 percentage points
in the rate of correct detection were achieved by means
of selective manipulation of the steering vibration
stimuli. The results also suggested, however, that no single setting of the MNMS algorithm proved optimal
for all three road surface types that were investigated
Recommended from our members
Effect of transient event frequency content and scale on the human detection of road surface type
This paper describes two laboratory-based experiments which evaluate the effect of transient event frequency
content and scale on the human detection of road surface type by means of steering wheel vibration. This study
used steering wheel tangential direction acceleration time histories which had been measured in a mid-sized
European automobile that was driven over two different types of road surface. The steering acceleration stimuli
were manipulated by means of the mildly non-stationary mission synthesis (MNMS) algorithm in order to
produce test stimuli which were selectively modified in terms of the number, and size, of transient vibration
events they contained. Fifteen test participants were exposed to both unmanipulated and manipulated steering
wheel rotational stimuli by means of a steering wheel vibration simulator. For each road surface type a total of
45 vibration test stimuli were presented to each participant. Each participant was asked to state, by means of a
simple "yes" or "no" answer, whether each individual stimuli was from a road surface which was being
presented in front of the simulator as a picture on a large board. Using Signal Detection Theory as the
analytical framework the results were summarized by means of the detectability index d' and by means of
receiver operating curve (ROC) points. Improvements of up to 20 percentage points in the rate of correct
detection were achieved by means of selective manipulation of the steering vibration stimuli. The results
suggested that no single setting of the MNMS algorithm proved optimal for both two road surface types that
were investigated
Optimal design of pipes in series: An explicit approximation
This paper introduces a new methodology for the optimum design of pipes in series, named Optimum Hydraulic Grade Line (OHGL). This methodology is explicit and is based on the knowledge of the series topology and the geometrical distribution of water demands on nodes, i.e. the way in which the pipe in series delivers water mass as function of the distance from the entrance. OHGL consists in the pre-determination of that hydraulic grade line which gives the minimum construction cost, in an explicit way. Once this line has been established, calculation of the pipe’s continuous diameters is direct; after a round up to commercial diameters is developed. To validate the proposed methodology, several pipes in series were designed both using GA and OHGL. Four hundred series were used in total, each with different topological characteristics and demands. Keywords: Pipe in series, optimum design, genetic algorithms, optimum hydraulic grade line
Efficient quantum simulation of fermionic and bosonic models in trapped ions
We analyze the efficiency of quantum simulations of fermionic and bosonic
models in trapped ions. In particular, we study the optimal time of entangling
gates and the required number of total elementary gates. Furthermore, we
exemplify these estimations in the light of quantum simulations of quantum
field theories, condensed-matter physics, and quantum chemistry. Finally, we
show that trapped-ion technologies are a suitable platform for implementing
quantum simulations involving interacting fermionic and bosonic modes, paving
the way for overcoming classical computers in the near future.Comment: 13 pages, 3 figures. Published in EPJ Quantum Technolog
Asymmetry studies in Lambda 0/Lambda 0-bar, Xi-/Xi+ and Omega-/Omega+ production
We present a study on hyperon/anti-hyperon production asymmetries in the
framework of the recombination model. The production asymmetries for Lambda
0/Lambda 0-bar, Xi-/Xi+ and Omega-/Omega+ are studied as a function of x_F.
Predictions of the model are compared to preliminary data on
hyperon/anti-hyperon production asymmetries in 500 GeV/c pi- p interactions
from the Fermilab E791 experiment. The model predicts a growing asymmetry with
the number of valence quarks shared by the target and the produced hyperons in
the x_F < 0 region. In the positive x_F region, the model predicts constant
asymmetries for Lambda 0/Lambda 0-bar and Omega-/Omega+ production and a
growing asymmetry with x_F for Xi-/Xi+. We found a qualitatively good agreement
between the model predictions and data, showing that recombination is a
competitive mechanism in the hadronization process.Comment: One reference correcte
Hyperon production asymmetries in 500 GeV/c pion nucleus interactions
We present a preliminary study from Fermilab experiment E791 of Lambda^0 /
Lambda^0 bar, Xi^- / Xi^+ and Omega^- /Omega^+ production asymmetries from pi^-
nucleus interactions at 500 Gev/c. The production asymmetries for these
particles are studied as a function of x_F and pt^2. We observed an asymmetry
in the target fragmentation region for Lambda^0's larger than that for Xi's,
suggesting diquark effects. The asymmetry for Omega's is significatively
smaller than for the other two hyperons consistent with the fact that Omega's
do not share valence quarks with either the pion or the target particle. In the
beam fragmentation region, the asymmetry tends to 0.1 for both Lambda^0's and
Xi's. The asymmetries vs pt^2 are approximately constant for the three strange
baryons under study.Comment: Typos correcte
Deep Strong Coupling Regime of the Jaynes-Cummings model
We study the quantum dynamics of a two-level system interacting with a
quantized harmonic oscillator in the deep strong coupling regime (DSC) of the
Jaynes-Cummings model, that is, when the coupling strength g is comparable or
larger than the oscillator frequency w (g/w > 1). In this case, the
rotating-wave approximation cannot be applied or treated perturbatively in
general. We propose an intuitive and predictive physical frame to describe the
DSC regime where photon number wavepackets bounce back and forth along parity
chains of the Hilbert space, while producing collapse and revivals of the
initial population. We exemplify our physical frame with numerical and
analytical considerations in the qubit population, photon statistics, and
Wigner phase space.Comment: Published version, note change of title: DSC regime of the JC mode
Switchable ultrastrong coupling in circuit QED
Superconducting quantum circuits possess the ingredients for quantum
information processing and for developing on-chip microwave quantum optics.
From the initial manipulation of few-level superconducting systems (qubits)
to their strong coupling to microwave resonators, the time has come to consider
the generation and characterization of propagating quantum microwaves. In this
paper, we design a key ingredient that will prove essential in the general
frame: a swtichable coupling between qubit(s) and transmission line(s) that can
work in the ultrastrong coupling regime, where the coupling strength approaches
the qubit transition frequency. We propose several setups where two or more
loops of Josephson junctions are directly connected to a closed (cavity) or
open transmission line. We demonstrate that the circuit induces a coupling that
can be modulated in strength and type. Given recent studies showing the
accessibility to the ultrastrong regime, we expect our ideas to have an
immediate impact in ongoing experiments
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