459 research outputs found
RESEARCH ON VIDEO-BASED HUMAN BODY MOTION TRACKING
The video-based motion capture system uses cheap equipments, like digital cameras and personal computers, to track a human motion without any sensors or markers attached to the body. This topic has a wide application in areas such as smart surveillance, human computer interaction and athletic performance analysis etc., and it becomes a hot topic of computer vision in recent years. Because of the complexity of the problem and lack of comprehension of human vision system essence, visual tracking is still hard in computer vision
Quark Propagation in the Quark-Gluon Plasma
It has recently been suggested that the quark-gluon plasma formed in
heavy-ion collisions behaves as a nearly ideal fluid. That behavior may be
understood if the quark and antiquark mean-free- paths are very small in the
system, leading to a "sticky molasses" description of the plasma, as advocated
by the Stony Brook group. This behavior may be traced to the fact that there
are relatively low-energy resonance states in the plasma leading to
very large scattering lengths for the quarks. These resonances have been found
in lattice simulation of QCD using the maximum entropy method (MEM). We have
used a chiral quark model, which provides a simple representation of effects
due to instanton dynamics, to study the resonances obtained using the MEM
scheme. In the present work we use our model to study the optical potential of
a quark in the quark-gluon plasma and calculate the quark mean-free-path. Our
results represent a specific example of the dynamics of the plasma as described
by the Stony Brook group.Comment: 17 pages, 4 figures, revtex
Do Demographic Characteristics Make Differences? Demographic Characteristics as Moderators in the Associations between Only Child Status and Cognitive/Non-cognitive Outcomes in China
Analysis of the dynamics of a delayed HIV pathogenesis model
AbstractIn this paper, considering full Logistic proliferation of CD4+ T cells, we study an HIV pathogenesis model with antiretroviral therapy and HIV replication time. We first analyze the existence and stability of the equilibrium, and then investigate the effect of the time delay on the stability of the infected steady state. Sufficient conditions are given to ensure that the infected steady state is asymptotically stable for all delay. Furthermore, we apply the Nyquist criterion to estimate the length of delay for which stability continues to hold, and investigate the existence of Hopf bifurcation by using a delay Ď„ as a bifurcation parameter. Finally, numerical simulations are presented to illustrate the main results
Calculation of Screening Masses in a Chiral Quark Model
We consider a simple model for the coordinate-space vacuum polarization
function which is often parametrized in terms of a screening mass. We discuss
the circumstances in which the standard result for the screening mass,
, is obtained. In the model considered here, that result is
obtained when the momenta in the relevant vacuum polarization integral are
small with respect to the first Matsubara frequency.Comment: 6 pages, 2 figure
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