Video streaming is one of the challenging issues in vehicular ad-hoc networks (VANETs) due to their highly dynamic topology and frequent connectivity disruptions. Recent developments in the routing protocol methods used in VANETs have contributed to improvements in the quality of experience (QoE) of the received video. One of these methods is the selection of the next-hop relay vehicle. In this paper, a QoE-aware geographic protocol for video streaming over VANETs is proposed. The selection process of the next relay vehicle is based on a correlated formula of QoE and quality of service (QoS) factors to enhance the users’ QoE. The simulation results show that the proposed GeoQoE-Vanet outperforms both GPSR and GPSR-2P protocols in providing the best end-user QoE of video streaming service.

A four quasiparticle high-K isomer with a meanlife of 45͑2͒ s has been identified at 1451 keV in 180 Ta, populated in the 176 Yb( 11 B,␣3n͒ 180 Ta reaction. The isomer decays into a rotational band which is associated with the two-quasiparticle 9 Ϫ isomer at 75.3 keV. Analysis of the branching ratios within that band and the magnetic moment for the 9 Ϫ isomer, supports the configuration assignment to the 9 Ϫ isomer. The K hindrance for the E2 decay of the 15 Ϫ isomer to the 9 Ϫ band is substantially lower than that for an apparently similar 15 Ϫ isomer in 178 Ta, a difference which can be attributed partly to a change from the 9/2 Ϫ ͓514͔ 3 9/2 ϩ ͓624͔7/2 Ϫ ͓514͔5/2 Ϫ ͓512͔ configuration in 178 Ta to the 3 9/2 Ϫ ͓514͔7/2 ϩ ͓404͔5/2 ϩ ͓402͔9/2 ϩ ͓624͔ configuration in 180 Ta. The reduced hindrance factors for E2 decays from related four-quasiparticle isomers in the isotopes 176,178,180 Ta match the hindrances of the corresponding E2 decays from component 6 ϩ core states in the hafnium isotopes, 174,176,178 Hf .

Broadband wireless technology, though aimed at video services, also poses a potential threat to video services, as wireless channels are prone to error bursts. In this paper, an adaptive, application-layer Forward Error Correction (FEC) scheme protects H.264/AVC data-partitioned video. Data partitioning is the division of a compressed video stream into partitions of differing decoding importance. The paper determines whether equal error protection (EEP) through FEC of all partition types or unequal error protection (UEP) of the more important partition type is preferable. The paper finds that, though UEP offers a small reduction in bitrate, if EEP is employed, there are significant gains (several dBs) in video quality. Overhead from using EEP rather than UEP was found to be around 1% of the overall bitrate. Given that data partitioning already reduces errors through packet size reduction and differentiation of coding data, EEP with data partitioning is a practical means of protecting user-based video streaming. The gain from employing EEP is shown to be higher quality video to the user, which will result in a greater take-up of video services. The results have implications for other forms of prioritized video streaming.

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The trend towards video streaming with increased spatial resolutions and\ud dimensions, SD, HD, 3D, and 4kUHD, even for portable devices has important\ud implications for displayed video quality. There is an interplay between\ud packetization, packet loss visibility, choice of codec, and viewing conditions,\ud which implies that prior studies at lower resolutions may not be as relevant.\ud This paper presents two sets of experiments, the one at a Variable BitRate\ud (VBR) and the other at a Constant BitRate(CBR), which highlight different\ud aspects of the interpretation. The latter experiments also compare and\ud contrast encoding with either an H.264 or an High Efficiency Video Coding\ud (HEVC) codec, with all results recorded as objective Mean Opinion Score\ud (MOS). The video quality assessments will be of interest to those considering:\ud the bitrates and expected quality in error-prone environments; or, in\ud fact, whether to use a reliable transport protocol to prevent all errors, at a\ud cost in jitter and latency, rather than tolerate low levels of packet errors