Shared teaching with multimedia‐enhanced video‐conferencing

Video‐conferencing was used to share a short series of lectures between several universities. A high bandwidth network (155Mbit/s) permitted near broadcast TV quality video to be combined with fully mixed, high‐quality audio. The lectures were supported by visual aids made available using Microsoft NetMeeting to provide multipoint, shared applications. NetMeeting is shown to be a stable and effective platform for distributing multimedia material at a much higher resolution than is possible using the video signals common in most video‐conference lectures, although care must be taken when constructing animated material

Successive Refinement with Decoder Cooperation and its Channel Coding Duals

We study cooperation in multi terminal source coding models involving successive refinement. Specifically, we study the case of a single encoder and two decoders, where the encoder provides a common description to both the decoders and a private description to only one of the decoders. The decoders cooperate via cribbing, i.e., the decoder with access only to the common description is allowed to observe, in addition, a deterministic function of the reconstruction symbols produced by the other. We characterize the fundamental performance limits in the respective settings of non-causal, strictly-causal and causal cribbing. We use a new coding scheme, referred to as Forward Encoding and Block Markov Decoding, which is a variant of one recently used by Cuff and Zhao for coordination via implicit communication. Finally, we use the insight gained to introduce and solve some dual channel coding scenarios involving Multiple Access Channels with cribbing.Comment: 55 pages, 15 figures, 8 tables, submitted to IEEE Transactions on Information Theory. A shorter version submitted to ISIT 201

Evaluation of the South Yorkshire Restorative Justice programme (SYRJP)

The SYRJP was developed in partnership between South Yorkshire Police and the Local Criminal Justice Board (LCJB) with the aim of implementing a county wide model of Restorative Justice (RJ) for use in neighbourhood policing and other community applications. It is aimed at tackling low level crime and anti-social behaviour in neighbourhoods and gives police officers the discretion to use Youth and Adult Restorative disposals as an alternative to prosecution for low level offending behaviour where offenders have no previous convictions, make an admission of guilt and where both offender and victim consent to the RJ process

The VITI program: Final Report

In this report we present our findings and results from the VITI program in 2000. The focus of the research work undertaken by VITI has been to provide electronic meeting environments that are easy to use and afford as natural a collaboration experience as possible. This final report is structured into three parts. Part one concerns the VITI infrastructure and consists of two sections. The first section describes the process of establishing the infrastructure, concentrating on how the work was done. The second section presents the actual infrastructure that is in place today, concentrating on what has been put in place. Part two examines the use the VITI infrastructure has been put to, giving examples of activities it has supported and discussing strengths and weaknesses that have emerged through this use. Finally part three considers the future of distributed electronic meeting environments. It is recommended that the report be read in the order in which it is presented. However, each section has been written as a standalone document and can be read independently of the others

Collaboration technology and space science

A summary of available collaboration technologies and their applications to space science is presented as well as investigations into remote coaching paradigms and the role of a specific collaboration tool for distributed task coordination in supporting such teleoperations. The applicability and effectiveness of different communication media and tools in supporting remote coaching are investigated. One investigation concerns a distributed check-list, a computer-based tool that allows a group of people, e.g., onboard crew, ground based investigator, and mission control, to synchronize their actions while providing full flexibility for the flight crew to set the pace and remain on their operational schedule. This autonomy is shown to contribute to morale and productivity

The 30/20 GHz fixed communications systems service demand assessment. Volume 3: Annex

A review of studies forecasting the communication market in the United States is given. The applicability of these forecasts to assessment of demand for the 30/20 GHz fixed communications system is analyzed. Costs for the 30/20 satellite trunking systems are presented and compared with the cost of terrestrial communications

"Real Places in Virtual Spaces"

Despite what might seem to be the case, "Virtual" reality can be used to create fully "real" places with their own grammar and norms, where real events take place

Loss-resilient Coding of Texture and Depth for Free-viewpoint Video Conferencing

Free-viewpoint video conferencing allows a participant to observe the remote 3D scene from any freely chosen viewpoint. An intermediate virtual viewpoint image is commonly synthesized using two pairs of transmitted texture and depth maps from two neighboring captured viewpoints via depth-image-based rendering (DIBR). To maintain high quality of synthesized images, it is imperative to contain the adverse effects of network packet losses that may arise during texture and depth video transmission. Towards this end, we develop an integrated approach that exploits the representation redundancy inherent in the multiple streamed videos a voxel in the 3D scene visible to two captured views is sampled and coded twice in the two views. In particular, at the receiver we first develop an error concealment strategy that adaptively blends corresponding pixels in the two captured views during DIBR, so that pixels from the more reliable transmitted view are weighted more heavily. We then couple it with a sender-side optimization of reference picture selection (RPS) during real-time video coding, so that blocks containing samples of voxels that are visible in both views are more error-resiliently coded in one view only, given adaptive blending will erase errors in the other view. Further, synthesized view distortion sensitivities to texture versus depth errors are analyzed, so that relative importance of texture and depth code blocks can be computed for system-wide RPS optimization. Experimental results show that the proposed scheme can outperform the use of a traditional feedback channel by up to 0.82 dB on average at 8% packet loss rate, and by as much as 3 dB for particular frames