Broadband wireless video streaming: achieving unicast and multicast IPTV in a practical manner

This paper proposes a versatile IPTV video-streaming scheme that provides high-quality unicast with the aid of repair packets but still supports multicast without repair packets. Prior research on wireless multicast video streaming has addressed the risk of feedback implosion when providing adaptive Forward Error Correction (FEC). This approach has not been adopted by providers, who may either prefer unicast streaming or employ a sufficient level of application-layer FEC to avoid the need for adaptation. Instead in this paper, an adaptive, unicast rateless channel-coding scheme is also run in multicast mode. The paper demonstrates the method and the operating conditions for such a joint unicast/multicast service in terms of data rates and suitable video-content type. Data-partitioned source coding with gradual decoding refresh is adopted in the given scenarios, making for a practical broadband wireless streaming scheme

Near-death experiences: actual considerations.

peer reviewedThe notion that death represents a passing to an afterlife, where we are reunited with loved ones and live eternally in a utopian paradise, is common in the anecdotal reports of people who have encountered a “near-death experience” (NDE). These experiences are usually portrayed as being extremely pleasant including features such as a feeling of peacefulness, the vision of a dark tunnel leading to a brilliant light, the sensation of leaving the body, or the experience of a life review. NDEs are increasingly being reported as a clearly identifiable physiological and psychological reality of clinical and scientific significance. The definition and causes of the phenomenon as well as the identification of NDE experiencers are still matters of debate. The phenomenon has been thoroughly portrayed by the media, but the science of NDEs is rather recent and still lacking of rigorous experimental data and reproducible controlled experiments. It seems that the most appropriate theories to explain the phenomenon tend to integrate both psychological and neurobiological mechanisms. The paradoxical dissociation between the richness and intensity of the memory, probably occurring during a moment of brain dysfunction, offers a unique opportunity to better understand the neural correlates of consciousness. In this chapter, we will attempt to describe NDEs and the methods to identify them. We will also briefly discuss the NDE experiencers’ characteristics. We will then address the main current explicative models and the science of NDEs