Articles
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09/20/2016--
09/20/2016
The JCMT Gould Belt Survey: Dense Core Clusters in Orion A
The Orion A molecular cloud is one of the most well-studied nearby
star-forming regions, and includes regions of both highly clustered and more
dispersed star formation across its full extent. Here, we analyze dense,
star-forming cores identified in the 850 {\mu}m and 450 {\mu}m SCUBA-2 maps
from the JCMT Gould Belt Legacy Survey. We identify dense cores in a uniform
manner across the Orion A cloud and analyze their clustering properties. Using
two independent lines of analysis, we find evidence that clusters of dense
cores tend to be mass segregated, suggesting that stellar clusters may have
some amount of primordial mass segregation already imprinted in them at an
early stage. We also demonstrate that the dense core clusters have a tendency
to be elongated, perhaps indicating a formation mechanism linked to the
filamentary structure within molecular clouds.
J. Lane
H. Kirk
D. Johnstone
S. Mairs
J. Di Francesco
S. Sadavoy
J. Hatchell
D. S. Berry
T. Jenness
M. R. Hogerheijde
D. Ward-Thompson
10/15/2020--
10/15/2020
To Lane or Not to Lane? Comparing On-Road Experiences in Developing and Developed Countries using a New Simulator "RoadBird"
Even though the traffic systems in developed countries have been analyzed
with rigor and operated efficiently, the same does not generally hold for
developing countries due to inadequate planning, design, and operations of
their transportation systems. Because of inherent differences between internal
infrastructures, the systems deployed in developed countries may not be
amenable to developing ones. Besides, the traffic systems of developing
countries are not well-studied in the literature to the best of our knowledge.
For example, it is yet to explore how a developed country's lane-based traffic
flow would perform in the context of a developing country, which generally
experiences non-lane-based traffic. As such, by using our newly developed
traffic simulator 'RoadBird', we investigate outcomes of both lane-based and
non-lane-based traffic from the contexts of both developing and developed
countries. To do so, we run simulations over real road topologies (extracted
from the GIS maps of major cities such as Dhaka, Miami, and Riyadh) considering
different scenarios such as lane-based or non-lane-based flows, homogeneous or
heterogeneous traffic, with or without pedestrians, etc. We also incorporate
different car-following and lane-changing models to mimic traffic behaviors and
investigate their performances. While the lane changing dilemma remains an open
research question, our experimental evidences indicate: (i) lane-based
approaches will not necessarily perform better in the case of currently-adopted
non-lane-based scenarios; and (ii) non-lane-based strategies may benefit system
performance in lane-based scenarios while having heavy mixed traffic.
Nonetheless, we reveal several new insights for on-road experiences both in
developing and developed countries.
Md. Masum Mushfiq
Tarik Reza Toha
Saiful Islam Salim
Aaiyeesha Mostak
Masfiqur Rahaman
Najla Abdulrahman Al-Nabhan
Arif Mohamin Sadri
A. B. M. Alim Al Islam
11/17/2006--
11/17/2006
The Complex Mid-Infrared Structure at the Heart of IRAS 20126+4104
The mid-infrared emission at the center of IRAS 21026+4104 is not that of a
simple compact source, as one would expect from an isolated high mass
protostellar object. Furthermore the central thermal infrared emission does not
appear to be coming directly from a circumstellar disk as has been recently
hypothesized from near-infrared observations. The mid-infrared structure is
complex, but with the help of multiple wavelength information two plausible
scenarios to explain the emission in the region are advanced. The first is that
there is a tight cluster of young stellar objects here. The second is that the
mid-infrared emission and masers are delineating the walls of the outflow
cavities of a massive stellar source located in the center of the near- and
mid-infrared dark lane.
James M. De Buizer
12/16/2008--
12/16/2008
Dynamics of lane formation in driven binary complex plasmas
The dynamical onset of lane formation is studied in experiments with binary
complex plasmas under microgravity conditions. Small microparticles are driven
and penetrate into a cloud of big particles, revealing a strong tendency
towards lane formation. The observed time-resolved lane formation process is in
good agreement with computer simulations of a binary Yukawa model with Langevin
dynamics. The laning is quantified in terms of the anisotropic scaling index,
leading to a universal order parameter for driven systems.
K. R. Sütterlin
A. Wysocki
A. V. Ivlev
C. Räth
H. M. Thomas
M. Rubin-Zuzic
W. J. Goedheer
V. E. Fortov
A. M. Lipaev
V. I. Molotkov
O. F. Petrov
G. E. Morfill
H. Löwen
03/24/2011--
03/24/2011
Phase diagram of two-lane driven diffusive systems
We consider a large class of two-lane driven diffusive systems in contact
with reservoirs at their boundaries and develop a stability analysis as a
method to derive the phase diagrams of such systems. We illustrate the method
by deriving phase diagrams for the asymmetric exclusion process coupled to
various second lanes: a diffusive lane; an asymmetric exclusion process with
advection in the same direction as the first lane, and an asymmetric exclusion
process with advection in the opposite direction. The competing currents on the
two lanes naturally lead to a very rich phenomenology and we find a variety of
phase diagrams. It is shown that the stability analysis is equivalent to an
`extremal current principle' for the total current in the two lanes. We also
point to classes of models where both the stability analysis and the extremal
current principle fail.
M. R. Evans
Y. Kafri
K. E. P. Sugden
J. Tailleur
01/13/2015--
01/13/2015
Robust and Real Time Detection of Curvy Lanes (Curves) with Desired Slopes for Driving Assistance and Autonomous Vehicles
One of the biggest reasons for road accidents is curvy lanes and blind turns.
Even one of the biggest hurdles for new autonomous vehicles is to detect curvy
lanes, multiple lanes and lanes with a lot of discontinuity and noise. This
paper presents very efficient and advanced algorithm for detecting curves
having desired slopes (especially for detecting curvy lanes in real time) and
detection of curves (lanes) with a lot of noise, discontinuity and
disturbances. Overall aim is to develop robust method for this task which is
applicable even in adverse conditions. Even in some of most famous and useful
libraries like OpenCV and Matlab, there is no function available for detecting
curves having desired slopes , shapes, discontinuities. Only few predefined
shapes like circle, ellipse, etc, can be detected using presently available
functions. Proposed algorithm can not only detect curves with discontinuity,
noise, desired slope but also it can perform shadow and illumination correction
and detect/ differentiate between different curves.
Amartansh Dubey
K. M. Bhurchandi
06/14/2017--
06/14/2017
Multi-Lane Perception Using Feature Fusion Based on GraphSLAM
An extensive, precise and robust recognition and modeling of the environment
is a key factor for next generations of Advanced Driver Assistance Systems and
development of autonomous vehicles. In this paper, a real-time approach for the
perception of multiple lanes on highways is proposed. Lane markings detected by
camera systems and observations of other traffic participants provide the input
data for the algorithm. The information is accumulated and fused using
GraphSLAM and the result constitutes the basis for a multilane clothoid model.
To allow incorporation of additional information sources, input data is
processed in a generic format. Evaluation of the method is performed by
comparing real data, collected with an experimental vehicle on highways, to a
ground truth map. The results show that ego and adjacent lanes are robustly
detected with high quality up to a distance of 120 m. In comparison to serial
lane detection, an increase in the detection range of the ego lane and a
continuous perception of neighboring lanes is achieved. The method can
potentially be utilized for the longitudinal and lateral control of
self-driving vehicles.
Alexey Abramov
Christopher Bayer
Claudio Heller
Claudia Loy
08/28/2018--
08/28/2018
Multiple Lane Detection Algorithm Based on Optimised Dense Disparity Map Estimation
Lane detection is very important for self-driving vehicles. In recent years,
computer stereo vision has been prevalently used to enhance the accuracy of the
lane detection systems. This paper mainly presents a multiple lane detection
algorithm developed based on optimised dense disparity map estimation, where
the disparity information obtained at time t_{n} is utilised to optimise the
process of disparity estimation at time t_{n+1}. This is achieved by estimating
the road model at time t_{n} and then controlling the search range for the
disparity estimation at time t_{n+1}. The lanes are then detected using our
previously published algorithm, where the vanishing point information is used
to model the lanes. The experimental results illustrate that the runtime of the
disparity estimation is reduced by around 37% and the accuracy of the lane
detection is about 99%.
Han Ma
Yixin Ma
Jianhao Jiao
M Usman Maqbool Bhutta
Mohammud Junaid Bocus
Lujia Wang
Ming Liu
Rui Fan
08/11/2019--
08/11/2019
Efficiency and Scalability of Multi-Lane Capsule Networks (MLCN)
Some Deep Neural Networks (DNN) have what we call lanes, or they can be
reorganized as such. Lanes are paths in the network which are data-independent
and typically learn different features or add resilience to the network. Given
their data-independence, lanes are amenable for parallel processing. The
Multi-lane CapsNet (MLCN) is a proposed reorganization of the Capsule Network
which is shown to achieve better accuracy while bringing highly-parallel lanes.
However, the efficiency and scalability of MLCN had not been systematically
examined. In this work, we study the MLCN network with multiple GPUs finding
that it is 2x more efficient than the original CapsNet when using
model-parallelism. Further, we present the load balancing problem of
distributing heterogeneous lanes in homogeneous or heterogeneous accelerators
and show that a simple greedy heuristic can be almost 50% faster than a naive
random approach.
Vanderson M. do Rosario
Mauricio Breternitz Jr.
Edson Borin
11/29/2017--
11/02/2017
Dynamical density functional theory analysis of the laning instability in sheared soft matter
Using dynamical density functional theory (DDFT) methods we investigate the
laning instability of a sheared colloidal suspension. The nonequilibrium
ordering at the laning transition is driven by non-affine particle motion
arising from interparticle interactions. Starting from a DDFT which
incorporates the non-affine motion, we perform a linear stability analysis that
enables identification of the regions of parameter space where lanes form. We
illustrate our general approach by applying it to a simple one-component fluid
of soft penetrable particles.
Alberto Scacchi
Andrew J. Archer
Joseph M. Brader
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