406 research outputs found
Correlations of flow harmonics in 2.76A TeV Pb--Pb collisions
Using the event-by-event viscous hydrodynamics VISH2+1 with MC-Glauber,
MC-KLN, and AMPT initial conditions, we investigate the correlations of flow
harmonics, including the symmetric cumulants , the normalized
symmetric cumulants , and the Pearson correlation coefficients
in 2.76A TeV Pb--Pb collisions. We find is sensitive to both initial conditions and the specific shear viscosity
. A comparison with the recent ALICE data show that our hydrodynamic
calculations can qualitatively describe the data of and
for various initial conditions, which demonstrate that ,
are correlated and , are anti-correlated. Meanwhile, the
predicted symmetric cumulants , , and reveal that and , and are correlated, and
are anti-correlated in most centrality classes. We also find and , which are insensitive to , are
mainly determined by corresponding and
correlators from the initial
state. In contrast, other and
correlators are influenced by both initial conditions and , which
illustrates the non-linear mode couplings in higher flow harmonics with .Comment: 10 pages, 7 figure
Is hadronic flow produced in p--Pb collisions at the Large Hadron Collider?
Using the Ultra-relativistic Quantum Molecular Dynamics ({\tt UrQMD}) model,
we investigate the azimuthal correlations in p--Pb collisions at
TeV. It is shown that the simulated hadronic p--Pb
system can not generate the collective flow signatures, but mainly behaves as a
non-flow dominant system. However, the characteristic
mass-ordering of pions, kaons and protons is observed in {\tt UrQMD}
simulations, which is the consequence of hadronic interactions and not
necessarily associated with strong fluid-like expansions.Comment: 4 pages, 4 figures, proceedings for the 12th International Conference
on Nucleus-Nucleus Collisions (21-26 June 2015, Catania
Investigating the correlations of flow harmonics in 2.76A TeV Pb--Pb collisions
This proceeding briefly summarizes our recent investigations on the
correlations of flow harmonics in 2.76A TeV Pb--Pb collisions with viscous
hydrodynamics {\tt VISH2+1}. We calculated both the symmetric cumulants
and the normalized symmetric cumulants , and
found and , and , and are
correlated, and , and are anti-correlated. We
also found are insensitive to the QGP viscosity, which are
mainly determined by the initial conditions.Comment: SQM2016 proceeding, 4pages, 2 figure
CROSS-LAYER CUSTOMIZATION PLATFORM FOR LOW-POWER AND REAL-TIME EMBEDDED APPLICATIONS
Modern embedded applications have become increasingly complex and diverse in their functionalities and requirements. Data processing, communication and multimedia signal processing, real-time control and various other functionalities can often need to be implemented on the same System-on-Chip(SOC) platform. The significant power constraints and real-time guarantee requirements of these applications have become significant obstacles for the traditional embedded system design methodologies. The general-purpose computing microarchitectures of these platforms are designed to achieve good performance on average, which is far from optimal for any particular application. The system must always assume worst-case scenarios, which results in significant power inefficiencies and resource under-utilization.
This dissertation introduces a cross-layer application-customizable embedded platform, which dynamically exploits application information and fine-tunes system components at system software and hardware layers. This is achieved with the close cooperation and seamless integration of the compiler, the operating system, and the hardware architecture. The compiler is responsible for extracting application regularities through static and profile-based analysis. The relevant application knowledge is propagated and utilized at run-time across the system layers through the judiciously introduced reconfigurability at both OS and hardware layers. The introduced framework comprehensively covers the fundamental subsystems of memory management and multi-tasking execution control
Recursive autoencoders based unsupervised feature learning for hyperspectral image classification
Joint Route Optimization and Multidimensional Resource Management Scheme for Airborne Radar Network in Target Tracking Application
In this article, we investigate the problem of joint route optimization and multidimensional resource management (JRO-MDRM) for an airborne radar network in target tracking application. The mechanism of the proposed JRO-MDRM scheme is to adopt the optimization technique to collaboratively design the flight route, transmit power, dwell time, waveform bandwidth, and pulselength of each airborne radar node subject to the system kinematic limitations and several resource budgets, with the aim of simultaneously enhancing the target tracking accuracy and low probability of intercept (LPI) performance of the overall system. The predicted Bayesian Cramér–Rao lower bound and the probability of intercept are calculated and employed as the metrics to gauge the target tracking performance and LPI performance, respectively. It is shown that the resulting optimization problem is nonlinear and nonconvex, and the corresponding working parameters are coupled in both objective functions, which is generally intractable. By incorporating the particle swarm optimization and cyclic minimization approaches, an efficient four-step solution algorithm is proposed to deal with the above problem. Extensive numerical results are provided to demonstrate the correctness and advantages of our developed scheme compared with other existing benchmarks
Overexpression of an isoform of AML1 in acute leukemia and its potential role in leukemogenesis
AML1/RUNX1 is a critical transcription factor in hematopoietic cell differentiation and proliferation. From the _AML1_ gene, at least three isoforms, _AML1a_, _AML1b_ and _AML1c_, are produced through alternative splicing. AML1a interferes with the function of AML1b/1c, which are often called AML1. In the current study, we found a higher expression level of _AML1a_ in ALL patients in comparison to the controls. Additionally, AML1a represses transcription from promotor of macrophage-colony simulating factor receptor (M-CSFR) mediated by AML1b, indicating that AML1a antagonized the effect of AML1b. In order to investigate the role of _AML1a_ in hematopoiesis and leukemogenesis _in vivo_, bone marrow mononuclear cells (BMMNCs) from mice were transduced with AML1a and transplanted into lethally irradiated mice, which develop lymphoblastic leukemia after transplantation. Taken together, these results indicate that overexpression of AML1a may be an important contributing factor to leukemogenesis
Absolute Wrong Makes Better: Boosting Weakly Supervised Object Detection via Negative Deterministic Information
Weakly supervised object detection (WSOD) is a challenging task, in which
image-level labels (e.g., categories of the instances in the whole image) are
used to train an object detector. Many existing methods follow the standard
multiple instance learning (MIL) paradigm and have achieved promising
performance. However, the lack of deterministic information leads to part
domination and missing instances. To address these issues, this paper focuses
on identifying and fully exploiting the deterministic information in WSOD. We
discover that negative instances (i.e. absolutely wrong instances), ignored in
most of the previous studies, normally contain valuable deterministic
information. Based on this observation, we here propose a negative
deterministic information (NDI) based method for improving WSOD, namely
NDI-WSOD. Specifically, our method consists of two stages: NDI collecting and
exploiting. In the collecting stage, we design several processes to identify
and distill the NDI from negative instances online. In the exploiting stage, we
utilize the extracted NDI to construct a novel negative contrastive learning
mechanism and a negative guided instance selection strategy for dealing with
the issues of part domination and missing instances, respectively. Experimental
results on several public benchmarks including VOC 2007, VOC 2012 and MS COCO
show that our method achieves satisfactory performance.Comment: 7 pages, 5 figure
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