14,360 research outputs found
Modeling of Packet Streaming Services in Information Communication Networks
Application of the term video streaming in contemporary usage denotes compression techniques and
data buffering, which can transmit video in real time over the network. There is currently a rapid growth
and development of technologies using wireless broadband technology as a transport, which is a seri-
ous alternative to cellular communication systems. Adverse effect of the aggressive environment used
in wireless networks transmission results in data packets undergoing serious distortions and often get-
ting lost in transit. All existing research in this area investigate the known types of errors separately. At
present there are no standard approaches to determining the effect of errors on transmission quality of
services. Besides, the spate in popularity of multimedia applications has led to the need for optimization
of bandwidth allocation and usage in telecommunication networks. Modern telecommunication networks
should by their definition be able to maintain the quality of different applications with different Quality
of Service (QoS) levels. QoS requirements are generally dependent on the parameters of network and
application layers of the OSI model. At the application layer QoS depends on factors such as resolution,
bit rate, frame rate, video type, audio codecs, and so on. At the network layer, distortions (such as delay,
jitter, packet loss, etc.) are introduced
Modeling, Simulation and Analysis of Video Streaming Errors in Wireless Wideband Access Networks
Analysis of simulated models has become a veritable tool for
investigating network behavioral patterns vis-à-vis transmitted content. The
streaming video research domain employs modeling extensively due to availability
of relevant tools. A vast majority of which are presented on the FOSS platform.
The transmission of audio and video streaming services over different media is
becoming ever more popular. This widespread increase is accompanied by the
difficult task of maintaining the QoS of streaming video. The use of very accurate
coding techniques for transmissions over wireless networks alone cannot guarantee
a complete eradication of distortions characteristic of the video signal. A software-
hardware composite system has been developed for investigating the effect of
single bit error and bit packet errors in wideband wireless access systems on the
quality of H.264/AVC standard video streams. Numerical results of the modeling
and analysis of the effect of interference robustness on quality of video streaming
are presented and discussed. Analytic results also suggest that the Markov model
of packetization of error obtained from a real network for streaming video can be
used in the simulations of transmission of video across networks in the hardware-
software complex developed by the authors in a previous work
Power Line Communication Technologies: Modeling and Simulation of PRIME Physical Layer
Power Line Communications is a relatively new
area of telecommunication. PLC employs full duplex methods
for transmitting data over power lines as medium of
transmission of electrical signals over a grid. PLC technologies
are used in advanced meter reading, home automation and
Public street lighting. Several PLC technologies classified
based on the operational frequency range, are explored in this
paper. PRIME is a new NBPLC system, which uses OFDM in
its physical layer, for power line communication in the last
mile. This work also focused on PRIME’s physical
specifications, which was modeled in MATLAB/SIMULINK.
In this paper, the performance of PRIME when its data is
modulated using DQPSK and 4-QAM in four (4) channel
models is shown.
Quark model description of the tetraquark state X(3872) in a relativistic constituent quark model with infrared confinement
We explore the consequences of treating the X(3872) meson as a tetraquark
bound state. As dynamical framework we employ a relativistic constituent quark
model which includes infrared confinement in an effective way. We calculate the
decay widths of the observed channels X-> Jpsi+2\pi (3\pi) and X-> \bar
D0+D0+\pi0 via the intermediate off--shell states X-> Jpsi+\rho(\omega) and X->
\bar D + D*. For reasonable values of the size parameter of the X(3872) we find
consistency with the available experimental data. We also discuss the possible
impact of the X(3872) in a s-channel dominance description of the
Jpsi-dissociation cross section.Comment: 9 pages, 5 figures; discussion and references added, accepted in
Phys. Rev.
Effect of Video Streaming Space–Time Characteristics on Quality of Transmission over Wireless Telecommunication Networks
The spate in popularity of multimedia applications
has led to the need for optimization of bandwidth allocation
and usage in telecommunication networks. Modern
telecommunication networks should by their definition be able to maintain the quality of different applications with different Quality of Service (QoS) levels. QoS requirements are generally dependent on the parameters of network and
application layers of the OSI model. At the application layer QoS depends on factors such as resolution, bit rate, frame rate, video type, audio codecs, etc. At the network layer, distortions such as delay, jitter, packet loss, etc. are introduced. This paper presents simulation results of modeling video streaming over wireless communications networks. The differences in spatial and time characteristics of the different subject groups
were taken into account. Analysis of the influence of bit error rate (BER) and bit rate for video quality is also presented.
Simulation showed that different video subject groups affect
the perceived quality differently when transmitted over
networks. We show conclusively that in a transmission network
with a small error probabilities (BER = 10-6, BER = 10-5), the
minimum bit rate (128 kbps) guarantees an acceptable video
quality, corresponding to MOS > 3 for all types of frames
Effect of Wideband Wireless Access Systems Interference Robustness on the Quality of Video Streaming
The transmission of audio and video streaming
services over different conduits (wireless access systems,
Internet, etc.) is becoming ever more popular. This widespread
increase is accompanied by the attendant new and difficult task
of maintaining the quality of service of streaming video. The use of very accurate coding techniques for transmissions over wireless networks alone cannot guarantee a complete eradication of distortions characteristic of the video signal. A software-hardware composite system has been developed for investigating the effect of single bit error and bit packet errors in wideband wireless access systems on the quality of H.264/AVC standard bursty video streams. Numerical results of the modeling and analysis of the effect of interference robustness on quality of video streaming are presented and discussed
Analytical representation of elastic scattering cross sections of low energy electrons by atmospheric gases
Analytical representations of the elastic scattering cross sections of electrons with energies of 0.01-1 keV in atmospheric gases of N2, O2, O are given. These representations are suitable for the Monte Carlo method
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