29,797 research outputs found
Pedestrian Flow Simulation Validation and Verification Techniques
For the verification and validation of microscopic simulation models of
pedestrian flow, we have performed experiments for different kind of facilities
and sites where most conflicts and congestion happens e.g. corridors, narrow
passages, and crosswalks. The validity of the model should compare the
experimental conditions and simulation results with video recording carried out
in the same condition like in real life e.g. pedestrian flux and density
distributions. The strategy in this technique is to achieve a certain amount of
accuracy required in the simulation model. This method is good at detecting the
critical points in the pedestrians walking areas. For the calibration of
suitable models we use the results obtained from analyzing the video recordings
in Hajj 2009 and these results can be used to check the design sections of
pedestrian facilities and exits. As practical examples, we present the
simulation of pilgrim streams on the Jamarat bridge.
The objectives of this study are twofold: first, to show through verification
and validation that simulation tools can be used to reproduce realistic
scenarios, and second, gather data for accurate predictions for designers and
decision makers.Comment: 19 pages, 10 figure
Studying the Dynamical Properties of 20 Nearby Galaxy Clusters
Using SDSS-DR7, we construct a sample of 42382 galaxies with redshifts in the
region of 20 galaxy clusters. Using two successive iterative methods, the
adaptive kernel method and the spherical infall model, we obtained 3396
galaxies as members belonging to the studied sample. The 2D projected map for
the distribution of the clusters members is introduced using the 2D adaptive
kernel method to get the clusters centers. The cumulative surface number
density profile for each cluster is fitted well with the generalized King
model. The core radii of the clusters' sample are found to vary from 0.18 Mpc
\mbox{h}^{-1} (A1459) to 0.47 Mpc \mbox{h}^{-1} (A2670) with mean value of
0.295 Mpc \mbox{h}^{-1}.
The infall velocity profile is determined using two different models, Yahil
approximation and Praton model. Yahil approximation is matched with the
distribution of galaxies only in the outskirts (infall regions) of many
clusters of the sample, while it is not matched with the distribution within
the inner core of the clusters. Both Yahil approximation and Praton model are
matched together in the infall region for about 9 clusters in the sample but
they are completely unmatched for the clusters characterized by high central
density. For these cluster, Yahil approximation is not matched with the
distribution of galaxies, while Praton model can describe well the infall
pattern of such clusters.Comment: 16 pages, 8 figure
Driver Distraction Identification with an Ensemble of Convolutional Neural Networks
The World Health Organization (WHO) reported 1.25 million deaths yearly due
to road traffic accidents worldwide and the number has been continuously
increasing over the last few years. Nearly fifth of these accidents are caused
by distracted drivers. Existing work of distracted driver detection is
concerned with a small set of distractions (mostly, cell phone usage).
Unreliable ad-hoc methods are often used.In this paper, we present the first
publicly available dataset for driver distraction identification with more
distraction postures than existing alternatives. In addition, we propose a
reliable deep learning-based solution that achieves a 90% accuracy. The system
consists of a genetically-weighted ensemble of convolutional neural networks,
we show that a weighted ensemble of classifiers using a genetic algorithm
yields in a better classification confidence. We also study the effect of
different visual elements in distraction detection by means of face and hand
localizations, and skin segmentation. Finally, we present a thinned version of
our ensemble that could achieve 84.64% classification accuracy and operate in a
real-time environment.Comment: arXiv admin note: substantial text overlap with arXiv:1706.0949
An emergent wall following behaviour to escape local minima for swarms of agents
Natural examples of emergent behaviour, in groups due to interactions among the group's individuals, are numerous. Our aim, in this paper, is to use complex emergent behaviour among agents that interact via pair-wise attractive and repulsive potentials, to solve the local minima problem in the artificial potential based navigation method. We present a modified potential field based path planning algorithm, which uses agent internal states and swarm emergent behaviour to enhance group performance. The algorithm is used successfully to solve a reactive path-planning problem that cannot be solved using conventional static potential fields due to local minima formation. Simulation results demonstrate the ability of a swarm of agents to perform problem solving using the dynamic internal states of the agents along with emergent behaviour of the entire group
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