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Multimedia broadcast and internet satellite system design and user trial results
The EU funded project, System for Advanced Multimedia Broadcast
and IT Services (SAMBITS), has created an enhanced and synchronised,
multimedia terminal for merging satellite broadcast and internet
telecommunication services in a way that efficiently combines the large
bandwidth of the broadcast channel and the interactivity of the internet.
This paper proposes a novel broadcast and internet service concept, illustrates
this concept with two service scenarios and develops a system architecture to
demonstrate the range of key benefits provided by these new technologies.
It then describes the interactive multimedia terminal that was used for
consuming this new service concept. Finally, the results of the user trials on the
terminal are presented and discussed
Studies on the bit rate requirements for a HDTV format with 1920 1080 pixel resolution, progressive scanning at 50 Hz frame rate targeting large flat panel displays
This paper considers the potential for an HDTV delivery format with 1920 times 1080 pixels progressive scanning and 50 frames per second in broadcast applications. The paper discusses the difficulties in characterizing the display to be assumed for reception. It elaborates on the required bit rate of the 1080p/50 format when critical content is coded in MPEG-4 H.264 AVC Part 10 and subjectively viewed on a large, flat panel display with 1920 times 1080 pixel resolution. The paper describes the initial subjective quality evaluations that have been made in these conditions. The results of these initial tests suggest that the required bit-rate for a 1080p/50 HDTV signal in emission could be kept equal or lower than that of 2nd generation HDTV formats, to achieve equal or better image qualit
Suppression of Charge Equilibration leading to the Synthesis of Exotic Nuclei
Charge equilibration between two colliding nuclei can take place in the early
stage of heavy-ion collisions. A basic mechanism of charge equilibration is
presented in terms of the extension of single-particle motion from one nucleus
to the other, from which the upper energy-limit of the bombarding energy is
introduced for significant charge equilibration at the early stage of the
collision. The formula for this limit is presented, and is compared to various
experimental data. It is examined also by comparison to three-dimensional
time-dependent density functional calculations. The suppression of charge
equilibration, which appears in collisions at the energies beyond the upper
energy-limit, gives rise to remarkable effects on the synthesis of exotic
nuclei with extreme proton-neutron asymmetry.Comment: 4 pages, 4 figure
Triaxial deformation in 10Be
The triaxial deformation in Be is investigated using a microscopic
model. The states of two valence neutrons are classified
based on the molecular-orbit (MO) model, and the -orbit is introduced
about the axis connecting the two -clusters for the description of the
rotational bands. There appear two rotational bands comprised mainly of and , respectively, at low excitation energy, where the two
valence neutrons occupy or orbits. The
triaxiality and the -mixing are discussed in connection to the molecular
structure, particularly, to the spin-orbit splitting. The extent of the
triaxial deformation is evaluated in terms of the electro-magnetic transition
matrix elements (Davydov-Filippov model, Q-invariant model), and density
distribution in the intrinsic frame. The obtained values turned out to be
.Comment: 15 pages, latex, 3 figure
Stochastic user behaviour modelling and network simulation for resource management in cooperation with mobile telecommunications and broadcast networks
The latest generations of telecommunications networks have been designed to deliver higher data rates than widely used second generation telecommunications networks, providing flexible communication capabilities that can deliver high quality video images. However, these new generations of telecommunications networks are interference limited, impairing their performance in cases of heavy traffic and high usage. This limits the services offered by a telecommunications network operator to those that the operator is confident their network can meet the demand for. One way to lift this constraint would be for the mobile telecommunications network operator to obtain the cooperation of a broadcast network operator so that during periods when the demand for the service is too high for the telecommunications network to meet, the service can be transferred to the broadcast network. In the United Kingdom the most recent telecommunications networks on the market are third generation UMTS networks while the terrestrial digital broadcast networks are DVB-T networks. This paper proposes a way for UMTS network operators to forecast the traffic associated with high demand services intended to be deployed on the UMTS network and when demand requires to transfer it to a cooperating DVB-T network. The paper aims to justify to UMTS network operators the use of a DVB-T network as a support for a UMTS network by clearly showing how using a DVB-T network to support it can increase the revenue generated by their network
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