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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

Finding Out How to Teach the Operant Quadrant: Content and Error Analysis

Auzenne, Jessica L 08 1900 (has links)
The goal of this study was to use a nonlinear approach to create a program to teach positive and negative reinforcement and punishment. A specific interest was to determine whether the program and its testing allowed for specific recommendations for future iterations of the program. The tests and program developed for this study were completed by 18 participants. Pre-test and post-test data showed that participants learned the most about positive contingencies, nonexample items, and ambiguous contingencies. Participants learned the least about negative contingencies. The data also revealed where additions to the instructional program were needed to produce better outcomes in future versions of the program.
452

A genetic risk score and number of myopic parents independently predict myopia

Ghorbani Mojarrad, Neema, Williams, C., Guggenheim, J.A. 08 November 2019 (has links)
Yes / Purpose: To investigate whether a genetic risk score (GRS) improved performance of predicting refractive error compared to knowing a child’s number of myopic parents (NMP) alone. Methods: This was a retrospective analysis of data from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort study. Refractive error was assessed longitudinally between age 7–15 using non-cycloplegic autorefraction. Genetic variants (n=149) associated with refractive error from a Consortium for Refractive Error And Myopia (CREAM) genome-wide association study were used to calculate a GRS for each child. Using refractive error at ages 7 and 15 years as the outcome variable, coefficient of determination (R2) values were calculated via linear regression models for the predictors: NMP, GRS and a combined model. Results: Number of myopic parents was weakly predictive of refractive error in children aged 7 years, R2=3.0% (95% CI 1.8–4.1%,p<0.0001) and aged 15 years, R2=4.8% (3.1–6.5%,p<0.0001). The GRS was also weakly predictive;age 7 years, R2=1.1% (0.4–1.9%,p<0.0001) and 15 years R2=2.6% (1.3–3.9%,p<0.0001). Combining the 2 variables gave larger R2 values at age 7, R2=3.7%(2.5–5.0%,p<0.0001) and 15, R2=7.0% (5.0–9.0%,p<0.0001). The combined model improved performance at both ages (both p<0.0001). Conclusion: A GRS improved the ability to detect children at risk of myopia independently of knowing the NMP. We speculate this may be because NMP captures information concerning environmental risk factors for myopia. Nevertheless, further gains are required to make such predictive tests worthwhile in the clinical environment. / The UK Medical Research Council and Wellcome. Grant Number: 102215/2/13/2 The University of Bristol provide core support for ALSPAC PDF. Grant Number: 459KB The College of Optometrists NIHR Senior Research Fellowship. Grant Number: SRF‐2015‐08‐005 23andMe
453

Adverse events in drug administration: a literature review

Armitage, Gerry R., Knapman, H. January 2003 (has links)
No / Discussions between the children's services manager at an National Health Service trust, and a children's nursing lecturer from the trust's partnering university clarified that there was a need to establish a greater understanding of the local circumstances surrounding adverse events in drug administration - particularly when those events involved nurses. Indeed it is claimed that nurses spend up to 40% of their time administering drugs. It was agreed that a collaborative research study, specifically designed to explore the nature of drug administration errors, could inform future trust policies and procedures around both drug administration and error, as well as the various university curricula concerning drug administration. This study, supported by senior management in the trust, and the chair of the local research ethics committee, has commenced. The first part of this study -- an introductory literature review, is presented here. The work of O'Shea [J Clin Nurs (1999)8:496-504] is significant in structuring the review that bears a number of recurring themes. It is not the intention of this literature review to reappraise O'Shea's original critique but to expand on her work, offer a contemporaneous perspective in the light of studies and reports published since 1999, and reset the topic in the context of clinical governance. This literature review has already provided an underpinning framework for a pilot questionnaire to staff who have been involved in drug administration errors and is also the basis for curricular input to preregistration students on the subject of risk management and drug administration. In conclusion, several recommendations about the shape of future research are offered.
454

Using ethnography (or qualitative methods) to investigate medication errors: a critique of a published study

Armitage, Gerry R., Hodgson, Ian J. 18 November 2009 (has links)
No / The effects of drug errors and any consequent adverse events frequently impact on patients, their relatives and professional carers. Furthermore, the financial cost to the National Health Service is considerable (DoH, 2000; DoH, 2001; DoH, 2004). In a study of two London teaching hospitals, Vincent et al. (2001) found that 10% of patients are exposed to an adverse event, which adds a mean 8.5 days to their hospital stay. Drug errors are recurrently reported to account for between 10 and 20% of all adverse events (DoH, 2004). In response to Department of Health policy, NHS trusts are changing their approach to the management of error to encourage more reporting. The emphasis is on openness and support, and individual and organisational learning rather than blame. Research designed to increase a knowledge of the aetiology and context of drug errors should be carefully constructed and include qualitative methods which, if implemented according to established convention, can reflect the approaches described above. This paper will critique a recently published study that focused on nursing practice and was, in our view, inappropriately described as ethnographic. The study undoubtedly adds to the body of existing knowledge about drug errors and, crucially, if the study contributes to improved patient safety, it must, fundamentally, be valued. Nevertheless, some qualitative research conventions were broken and, as such, it is suggested, some opportunities for a broader understanding and for learning may have been lost. The critique will lead to a range of recommendations about future qualitative studies in this research domain which, it is argued, could produce a fuller picture of the context, culture and, perhaps, even the cause of error.
455

BEST SOURCE SELECTORS AND MEASURING THE IMPROVEMENTS

Gatton, Tim 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / After years of tracing the evolution and solutions to finding the best data, I learned that it isn’t best source selection that we all want. What we need is best data selection.
456

LOW DENSITY PARITY CHECK CODES FOR TELEMETRY APPLICATIONS

Hayes, Bob 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Next generation satellite communication systems require efficient coding schemes that enable high data rates, require low overhead, and have excellent bit error rate performance. A newly rediscovered class of block codes called Low Density Parity Check (LDPC) codes has the potential to revolutionize forward error correction (FEC) because of the very high coding rates. This paper presents a brief overview of LDPC coding and decoding. An LDPC algorithm developed by Goddard Space Flight Center is discussed, and an overview of an accompanying VHDL development by L-3 Communications Cincinnati Electronics is presented.
457

Use of microcomputers in mathematics in Hong Kong higher education

Pong, Tak-Yun G. January 1988 (has links)
Since the innovation of computers some 40 years ago and the introduction of microcomputers in 1975, computers are playing an active role in education processes and altering the pattern of interaction between teacher and student in the classroom. Computer assisted learning has been seen as a revolution in education. In this research, the author has studied the impact of using microcomputers on mathematical education, particularly at the Hong Kong tertiary level, in different perspectives. Two computer software packages have been developed on the microcomputer. The consideration of the topic to be used in the computer assisted learning was arrived at in earlier surveys with students who thought that computers could give very accurate solutions to calculations. The two software packages, demonstrating on the spot the error that would be incurred by the computer, have been used by the students. They are both interactive and make use of the advantages of the microcomputer's functions over other teaching media, such as graphics facility and random number generator, to draw to the students' attention awareness of errors that may be obtained using computers in numerical solutions. Much emphasis is put on the significance and effectiveness of using computer packages in learning and teaching. Measurements are based on questionnaires, conversations with students, and tests on content material after the packages have been used. Feedback and subjective opinion of using computers in mathematical education have also been obtained from both students and other teachers. The research then attempts to examine the suitability of applying computer assisted learning in Hong Kong education sectors. Some studies on the comments made by students who participated in the learning process are undertaken. The successes and failures in terms of student accomplishment and interest in the subject area as a result of using a software package is described. Suggestions and recommendations are given in the concluding chapter.
458

USING SHORT-BLOCK TURBO CODES FOR TELEMETRY AND COMMAND

Wang, Charles C., Nguyen, Tien M. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The turbo code is a block code even though a convolutional encoder is used to construct codewords. Its performance depends on the code word length. Since the invention of the turbo code in 1993, most of the bit error rate (BER) evaluations have been performed using large block sizes, i.e., sizes greater than 1000, or even 10,000. However, for telemetry and command, a relatively short message (<500 bits) may be used. This paper investigates the turbo-coded BER performance for short packets. Fading channel is also considered. In addition, biased channel side information is adopted to improve the performance.
459

Error resilience and concealment in MVC video over wireless networks

Ibrahim, Abdulkareem B. January 2015 (has links)
Multi-view video is capable of presenting a full and accurate depth perception of a scene. The concept of multi-view video is becoming more useful especially in 3D display systems by enhancing the viewing of high resolution stereoscopic images from arbitrary viewpoints without the use of any special glasses. Like monoscopic video, the multi-view video is faced with different challenges such as: reliable compression, storage and bandwidth due to the increased number of views as well as the high sensitivity to transmission errors. All these may lead to a detrimental effect on the reconstructed views. The work in this thesis investigates the problems and challenges of transmission losses in a multi-view video bitstream over error prone wireless networks. Based on the network simulation results, the proposed technique is capable of addressing the problem of transmission losses. In practical wireless networks, transmission errors are inevitable and pose a serious challenge to the coded video data. The aim of this research effort is to examine the effect of these errors in a multi-view video bitstream when transmitted over a lossy channel. Moreover, this research work aims to develop a novel scheme that can make the multi-view coded videos more robust to transmission errors by minimizing the error effects and improving the perceptual quality. Multi-layer data partitioning as an error resilient technique is developed in JMVC 8.5 reference software in order to make the multi-view video bitstream more robust during transmission. In addition to that, we propose a simple decoding scheme that can support the decoding of the multi-layer data partitioning bitstream over channels with high error rate. The proposed technique is benchmarked with the already existing H.264/AVC data partitioning technique. The work in this thesis also employs the use of group of pictures as a coding parameter to investigate and reduce the effects of transmission errors in multi-view video transmitted over a very high error rate channel. The experiments are carried out with different error loss rates in order to evaluate the performance of these techniques in terms of perceptual quality when transmitted over a simulated erroneous channel. Errors are introduced using the Sirannon network simulator. The error performance of each technique is evaluated and analysed both objectively and subjectively after reconstruction. The results of the research investigation and simulation are presented and analysed in chapter six of the thesis.
460

Feedback Related Negativity: Reward Prediction Error or Salience Prediction Error?

Heydari, Sepideh 07 April 2015 (has links)
The reward positivity is a component of the human event-related brain potential (ERP) elicited by feedback stimuli in trial-and-error learning and guessing tasks. A prominent theory holds that the reward positivity reflects a reward prediction error that is differentially sensitive to the valence of the outcomes, namely, larger for unexpected positive events relative to unexpected negative events (Holroyd & Coles, 2002). Although the theory has found substantial empirical support, most of these studies have utilized either monetary or performance feedback to test the hypothesis. However, in apparent contradiction to the theory, a recent study found that unexpected physical punishments (a shock to the finger) also elicit the reward positivity (Talmi, Atkinson, & El-Deredy, 2013). Accordingly, these investigators argued that this ERP component reflects a salience prediction error rather than a reward prediction error. To investigate this finding further, I adapted the task paradigm by Talmi and colleagues to a more standard guessing task often used to investigate the reward positivity. Participants navigated a virtual T-maze and received feedback on each trial under two conditions. In a reward condition the feedback indicated that they would either receive a monetary reward or not for their performance on that trial. In a punishment condition the feedback indicated that they would receive a small shock or not at the end of the trial. I found that the feedback stimuli elicited a typical reward positivity in the reward condition and an apparently delayed reward positivity in the punishment condition. Importantly, this signal was more positive to the stimuli that predicted the omission of a possible punishment relative to stimuli that predicted a forthcoming punishment, which is inconsistent with the salience hypothesis. / Graduate / 0633 / 0317 / heydari@uvic.ca

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