2,364 research outputs found

    Interference Aspects of Adaptive Modems over Slow Rayleigh Fading Channels

    No full text
    Adaptive modulation can achieve channel capacity gains by adapting the number of bits per transmission symbol on a burst-by-burst basis, in harmony with channel quality fluctuations. This is demonstrated in the paper for target bit error rates of 1 and 0.01%, respectively, in comparison to conventional fixed modems. However, the achievable gains depend strongly on the prevalent interference levels and hence interference cancellation is invoked on the basis of adjusting the demodulation decision boundaries after estimating the interfering channel’s magnitude and phase. Using the modem-mode switching levels of Table X and with the aid of interference cancellation, target BERs of 1 and 0.01% can be maintained over slow-fading channels for a wide range of channel Signal-to-noise ratios (SNR) and Signal-to-interference ratios (SIR), as seen in Figs. 20 and 21, respectively. Index Terms—Burst-by-burst adaptive modulation (modems), cochannel interference, interference cancellation

    The design, development and survey reaction to a normative form of clinically oriented optometric software

    Get PDF
    Software was written to aid the Doctor of Optometry in providing a more detailed, precise and time efficient form of case analysis (normative). A survey of practitioner opinion was also conducted (in DHSS Region X) to assess their value of this type of software and to solicit ideas on their needs. The survey results indicated a limited interest and application for case analysis programming and a much greater interest in business oriented software

    Optimisation of switching levels for adaptive modulation in slow Rayleigh fading

    Full text link

    DEVELOPMENT OF EXPERIMENTS FOR THE HARVESTING AND STORING OF VIDALIA SWEET ONIONS

    Get PDF
    Sweet onions brought in nearly $70 million in 1998. Sweet onions have a soft bulb which makes them susceptible to injury if handled too roughly. Once injured, invasion by pathogens tends to render the bulbs unusable except for quick sale. They were harvested by hand until about ten years ago when efforts were begun to develop a mechanical harvester. Also, at that time, work was underway to develop a way of storing part of the crop so as to extend the market window beyond the traditional 6-8 weeks. Low temperature and low oxygen atmosphere conditions proved to be the most suitable. In 1998 and 1999, sweet onions were hand and machine harvested. They were stored for 30 weeks to determine the practicality of extending the market window. Storability of onions in bulk from the two harvest methods were compared using a mixed model analysis. A mixed model analysis was done on all the research data collected between 1992 and 1998 on curing and storing onions

    What Can Open Access Do for Me? Personal Perspectives of KU Faculty

    Get PDF
    Four University of Kansas faculty presented as panelists during this event. Slides from their presentations are shared here

    Bluebelle pilot randomised controlled trial of three wound dressing strategies to reduce surgical site infection in primary surgical wounds

    Get PDF
    Objective Surgical site infection (SSI) affects up to 25% of primary surgical wounds. Dressing strategies may influence SSI risk. The Bluebelle study assessed the feasibility of a multicentre randomised controlled trial (RCT) to evaluate the effectiveness and cost-effectiveness of different dressing strategies to reduce SSI in primary surgical wounds. Design A pilot, factorial RCT. Setting Five UK hospitals. Participants Adults undergoing abdominal surgery with a primary surgical wound. Interventions Participants were randomised to ‘simple dressing’, ‘glue-as-a-dressing’ or ‘no dressing’, and to the time at which the treatment allocation was disclosed to the surgeon (disclosure time, before or after wound closure). Primary and secondary outcome measures Feasibility outcomes focused on recruitment, adherence to randomised allocations, reference assessment of SSI and response rates to participant-completed and observer-completed questionnaires to assess SSI (proposed primary outcome for main trial), wound experience and symptoms, and quality of life (EQ-5D-5L). Results Between March and November 2016, 1115 patients were screened; 699 (73.4%) were eligible and approached, 415 (59.4%) consented and 394 (35.3%) were randomised (simple dressing=133, glue=129 and ‘no dressing’=132). Non-adherence to dressing allocation was 2% (3/133), 6% (8/129) and 15% (20/132), respectively. Adherence to disclosure time was 99% and 86% before and after wound closure, respectively. The overall rate of SSI (reference assessment) was 18.1% (51/281). Response rates to the Wound Healing Questionnaire and other questionnaires ranged from >90% at 4 days to 68% at 4–8 weeks. Conclusions A definitive RCT of dressing strategies including ‘no dressing’ is feasible. Further work is needed to optimise questionnaire response rates

    Formality and informality in the summative assessment of motor vehicle apprentices: a case study

    Get PDF
    This article explores the interaction of formal and informal attributes of competence‐based assessment. Specifically, it presents evidence from a small qualitative case study of summative assessment practices for competence‐based qualifications within apprenticeships in the motor industry in England. The data are analysed through applying an adaptation of a framework for exploring the interplay of formality and informality in learning. This analysis reveals informal mentoring as a significant element which influences not only the process of assessment, but also its outcomes. We offer different possible interpretations of the data and their analysis, and conclude that, whichever interpretation is adopted, there appears to be a need for greater capacity‐building for assessors at a local level. This could acknowledge a more holistic role for assessors; recognise the importance of assessors’ informal practices in the formal retention and achievement of apprentices; and enhance awareness of inequalities that may be reinforced by both informal and formal attributes of assessment practices

    Teachers' classroom feedback: still trying to get it right

    Get PDF
    This article examines feedback traditionally given by teachers in schools. Such feedback tends to focus on children's acquisition and retrieval of externally prescribed knowledge which is then assessed against mandated tests. It suggests that, from a sociocultural learning perspective, feedback directed towards such objectives may limit children's social development. In this article, I draw on observation and interview data gathered from a group of 27 9- to 10-year olds in a UK primary school. These data illustrate the children's perceived need to conform to, rather than negotiate, the teacher's feedback comments. They highlight the children's sense that the teacher's feedback relates to school learning but not to their own interests. The article also includes alternative examples of feedback which draw on children's own inquiries and which relate to the social contexts within which, and for whom, they act. It concludes by suggesting that instead of looking for the right answer to the question of what makes teachers' feedback effective in our current classrooms, a more productive question might be how a negotiation can be opened up among teachers and learners themselves, about how teachers' feedback could support children's learning most appropriately
    corecore