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With the advent of 5G+ services, it has become increasingly convenient for mobile users to enjoy high-quality multimedia content from CDN driven streaming and catch-up TV services (Netflix, iPlayer) in the (post-) COVID over-the-top (OTT) content rush. To relieve ISP owned fixed-line networks from CDN streamed multimedia traffic, system ideas (e.g., Wi-Stitch in [45]) have been proposed to (a) leverage 5G services and enable consumers to share cached multimedia content at the edge, and (b) consequently, and more importantly, reduce IP traffic at the core network. Unfortunately, given that contemporary multimedia content might be a monetized asset, these ideas do not take this important fact into account for shared content. We present EdgeMart--a content provider (CP) federated, and computationally sustainable networked (graphical) market economy for paid-sharing of cached licensed (OTT) content with autonomous users of a wireless edge network (WEN). EdgeMart is a unique oligopoly multimedia market (economy) that comprises competing networked sub-markets of non-cooperative content sellers/buyers--each sub-market consisting of a single buyer connected (networked) to only a subset of sellers. We prove that for any WEN-supported supply-demand topology, a pure strategy EdgeMart equilibrium exists that is (a) nearly efficient (in a microeconomic sense) indicating economy sustainability, (b) robust to edge user entry/exit, and (c) can be reached in poly-time (indicating computational sustainability). In addition, we experimentally show that for physical WENs of varying densities, a rationally selfish EdgeMart economy induces similar orders of multimedia IP traffic savings when compared to the ideal (relatively less practical), altruistic, and non-monetized "economy" implemented atop the recently introduced Wi-Stitch WEN-based content trading architecture. Moreover, the EdgeMart concept helps envision a regulated edge economy of opportunistic (pay per licensed file) client services for commercial OTT platforms. [ABSTRACT FROM AUTHOR]

The demand and usage of 360° video services are expected to increase. However, despite these services being highly bandwidth intensive, not much is known about the potential value that basic bandwidth saving techniques such as server or edge-network on-demand caching (e.g., in a CDN) could have when used for delivery of such services. This problem is both important and complicated as client-side solutions have been developed that split the full 360° view into multiple tiles, and adapt the quality of the downloaded tiles based on the user's expected viewing direction and bandwidth conditions. This article presents new trace-based analysis methods that incorporate users' viewports (the area of the full 360° view the user actually sees), a first characterization of the cross-user similarities of the users' viewports, and a trace-based analysis of the potential bandwidth savings that caching-based techniques may offer under different conditions. Our analysis takes into account differences in the time granularity over which viewport overlaps can be beneficial for resource saving techniques, compares and contrasts differences between video categories, and accounts for uncertainties in the network conditions and the prediction of the future viewing direction when prefetching. The results provide substantial insight into the conditions under which overlap can be considerable and caching effective, and inform the design of new caching system policies tailored for 360° video. [ABSTRACT FROM AUTHOR]

We developed and tested geographically weighted Poisson regression and geographically weighted negative binomial regression models using five year's collisions, traffic, socio-demographic, road inventory, and land use data for Regina, Saskatchewan, Canada. The need for geographically weighted models became clear when Moran's I local indicator showed that our study data contained statistically significant levels of spatial autocorrelation. Bandwidth is a required input for geographically weighted regression models. We tested fixed and adaptive bandwidths. We found that fixed bandwidth was more suitable than adaptive bandwidth in our study. Models that used fixed and adaptive bandwidth produced a wide range of parameters across zones. We think the wide range of parameters helped explain unobserved heterogeneity issues within the zones. To compare the geographically weighted Poisson and geographically weighted negative binomial models, we applied seven well-known goodness-of-fit tests. The results were inconsistent, but the cumulative residual plot developed for each model showed that the fixed bandwidth geographically weighted Poisson model and the geographically weighted negative binomial model were better at predicting collisions than were the adaptive bandwidth models. Based on the CURE plots obtained, we concluded that the geographically weighted negative binomial model with fixed bandwidth was the best model for our study data. [ABSTRACT FROM AUTHOR]

Human listening tests were conducted to investigate if participants could distinguish between samples of target echoes and clutter obtained from a broadband active sonar experiment. For each echo, the listeners assigned a rating based on how confident they were that it was a target echo or clutter. The measure of performance was the area under the binormal receiver-operating-characteristic (ROC) curve, Az. The mean performance was Az = 0.95 ± 0.04 when signals were presented with their full available acoustic bandwidth of approximately 0-2 kHz. It was Az = 0.77 ± 0.08 when the bandwidth was reduced to 0.5-2 kHz. The error bounds are stated as 95% confidence intervals. These results show that the listeners could definitely hear differences, but their performance was significantly degraded when the low-frequency signal information was removed. The performance of an automatic aural classifier was compared against this human-performance baseline. Results of statistical tests showed that it outperformed 2 of 13 listeners and 5 of 9 human listeners in the full-bandwidth and reduced-bandwidth tests, respectively, and performed similarly to the other listeners. Given its performance, the automatic aural classifier may prove beneficial to Navy sonar systems. [ABSTRACT FROM AUTHOR]

The paper presents the design guidelines for Active SAR Antennas followed for the development of COSMO SkyMed SAR Antenna Subsystem. They have brought to define the antenna architecture, the RF, and electrical requirements for all the antenna RF, digital and power units, taking into account the available technologies and achievable performance. The antenna design is described for what the main subsystems is concerned, such as RF, power, digital, including mechanical and thermal aspects. Finally the paper reports also a brief description of the most recent development carried out in Canada and in Europe in the last ten years, including the on-going programs. [ABSTRACT FROM AUTHOR]

A low-bandwidth telemedicine system was evaluated in eight community hospitals connected to a central hospital via the Internet. PCs were used with videoconferencing software and modem connections to the telephone network. The average data connection rates, still-image transfer times and live-video transmission rates were determined. The time to send 640 x 480, 320 x 240 and 160 x 120 pixel, 24-bit still images ranged from 29 s to 411 s. The average file transfer times for a 10 s MPEG video-clip was 8.6 min. The average live video frame rate was 1 frame/s (at the best image quality), with an average latency of 3 s. The results suggest that Internet-based videoconferencing is acceptable for certain telemedicine applications. [ABSTRACT FROM AUTHOR]

The Metal Earth project acquired 927 km of deep seismic reflection profiles from August to November of 2017. Seismic data acquired in this early stage of the Metal Earth project benefited greatly from recent advances in the petroleum sector as well as those in mineral exploration. Vibroseis acquisition with receivers having a 5 Hz response (10 dB down) generated records from a sweep signal starting at 2 Hz, sweeping up to 150 Hz or 200 Hz. Not only does this broadband signal enhance reflections from the deepest to the shallowest crust, but it also helps the use of full waveform inversion (e.g., to mitigate cycle-skipping) and related techniques. Metal Earth regional-scale transects using over 5000 active sensors target mineralizing fluid pathways throughout the crust, whereas higher spatial-resolution reflection and full-waveform surveys target structures at mine camp scales. Because Metal Earth was proposed to map and compare entire Archean ore and geologically similar non-ore systems, regional sections cover the entire crust to the Moho in the Abitibi and Wabigoon greenstone belts of the Superior craton in central Canada. Where the new sections overlap with previous Lithoprobe surveys, a clear improvement in reflector detection and definition is observed. Improvements are here attributed to the increased bandwidth of the signal, better estimates of refraction and reflection velocities used in processing, and especially the pre-stack time migration of the data. [ABSTRACT FROM AUTHOR]

This article presents information on conferences and conventions in 2005 related to digital communication in different parts of the world. Some of the conference listed were MAPE 2005, IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications on 8-12 August at Beijing, China,QSH1NE 2005, 2nd International Conference on Quality of Service in Heterogeneous Wired/Wireless Networks on 22-24 August at Orlando,Florida,LANOMS 2005, 4th Latin American Network Operations and Management Symposium on 29-31 August at Porto Alegre, Brazil,MC-SS 2005, 5th international Workshop on Multi-Carrier Spread Spectrum on 14-17 September at Germany,BMW 2005, IEEE Bandwidth Management Workshop on 3-6 October at Canada, DRCN 2005, 5th International Workshop on Design of Reliable Communication Networks on 16-19 October at island of Ischia, Italy and HONET 2005, on High Capacity Optical Networks and Enabling Technologies on 19-21 December at Islamabad, Pakistan.