On-board processing satellite network architecture and control study

For satellites to remain a vital part of future national and international communications, system concepts that use their inherent advantages to the fullest must be created. Network architectures that take maximum advantage of satellites equipped with onboard processing are explored. Satellite generations must accommodate various services for which satellites constitute the preferred vehicle of delivery. Such services tend to be those that are widely dispersed and present thin to medium loads to the system. Typical systems considered are thin and medium route telephony, maritime, land and aeronautical radio, VSAT data, low bit rate video teleconferencing, and high bit rate broadcast of high definition video. Delivery of services by TDMA and FDMA multiplexing techniques and combinations of the two for individual and mixed service types are studied. The possibilities offered by onboard circuit switched and packet switched architectures are examined and the results strongly support a preference for the latter. A detailed design architecture encompassing the onboard packet switch and its control, the related demand assigned TDMA burst structures, and destination packet protocols for routing traffic are presented. Fundamental onboard hardware requirements comprising speed, memory size, chip count, and power are estimated. The study concludes with identification of key enabling technologies and identifies a plan to develop a POC model

Castleman disease and lymphocytic interstitial pneumonia: a complex diagnostic and management challenge

No abstract available

Three applications for mobile epidemic algorithms

This paper presents a framework for the pervasive sharing of data using wireless networks. 'FarCry' uses the mobility of users to carry files between separated networks. Through a mix of ad-hoc and infrastructure-based wireless networking, files are transferred between users without their direct involvement. As users move to different locations, files are then transmitted on to other users, spreading and sharing information. We examine three applications of this framework. Each of these exploits the physically proximate nature of social gatherings. As people group together in, for example, business meetings and cafés, this can be taken as an indication of similar interests, e.g. in the same presentation or in a type of music. MediaNet affords sharing of media files between strangers or friends, MeetingNet shares business documents in meetings, and NewsNet shares RSS feeds between mobile users. NewsNet also develops the use of pre-emptive caching: collecting information from others not for oneself, but for the predicted later sharing with others. We offer observations on developing this system for a mobile, multi-user, multi-device environment

On the Perils of Security Pricing by Financial Intermediaries: The Case of Open-End Mutual Funds

There are many instances where financial claims trade at prices set by intermediaries. Pricing by an intermediary introduces the potential for economic distortions from innumerable sources. As one example, we show that nonsynchronous-trading generates predictable, readily exploitable, changes in mutual fund-share prices (NAV). The exploitation of predictable changes in mutual fund NAVs involved a wealth transfer from buy-and-hold fund investors to active fund traders and is costly to all fund investors. A simple modification to the mutual fund pricing algorithm eliminates much of this predictability, but nonsynchronous trading is just one of the issues intermediaries face when setting prices.

Supporting ethnographic studies of ubiquitous computing in the wild

Ethnography has become a staple feature of IT research over the last twenty years, shaping our understanding of the social character of computing systems and informing their design in a wide variety of settings. The emergence of ubiquitous computing raises new challenges for ethnography however, distributing interaction across a burgeoning array of small, mobile devices and online environments which exploit invisible sensing systems. Understanding interaction requires ethnographers to reconcile interactions that are, for example, distributed across devices on the street with online interactions in order to assemble coherent understandings of the social character and purchase of ubiquitous computing systems. We draw upon four recent studies to show how ethnographers are replaying system recordings of interaction alongside existing resources such as video recordings to do this and identify key challenges that need to be met to support ethnographic study of ubiquitous computing in the wild

Educational interventions to improve people's understanding of key concepts in assessing the effects of health interventions: a systematic review

Abstract Background Health information is readily accessible but is of variable quality. General knowledge about how to assess whether claims about health interventions are trustworthy is not common, so people’s health decisions can be ill-informed, unnecessarily costly and even unsafe. This review aims to identify and evaluate studies of educational interventions designed to improve people’s understanding of key concepts for evaluating claims about the effects of health interventions. Methods/Design We searched multiple electronic databases and sources of grey literature. Inclusion criteria included all study types that included a comparison, any participants (except health professionals or health professional students) and educational interventions aimed at improving people’s understanding of one or more of the key concepts considered necessary for assessing health intervention claims. Knowledge and/or understanding of concepts or skills relevant to evaluating health information were our primary outcome measures. Secondary outcomes included behaviour, confidence, attitude and satisfaction with the educational interventions. Two authors independently screened search results, assessed study eligibility and risk of bias and extracted data. Results were summarised using descriptive synthesis. Results Among 24 eligible studies, 14 were randomised trials and 10 used other study designs. There was heterogeneity across study participants, settings and educational intervention type, content and delivery. The risk of bias was high in at least one domain for all randomised studies. Most studies measured outcomes immediately after the educational intervention, with few measuring later. In most of the comparisons, measures of knowledge and skills were better among those who had received educational interventions than among controls, and some of these differences were statistically significant. The effects on secondary outcomes were inconsistent. Conclusions Educational interventions to improve people’s understanding of key concepts for evaluating health intervention claims can improve people’s knowledge and skills, at least in the short term. Effects on confidence, attitude and behaviour are uncertain. Many of the studies were at moderate or greater risk of bias. Improvements in study quality, consistency of outcome measures and measures of longer-term effects are needed to improve confidence in estimates of the effects of educational interventions to improve people’s understanding of key concepts for evaluating health intervention claims. Systematic review registration PROSPERO CRD4201603310