28,987 research outputs found

    Performance of the ICAO standard core service modulation and coding techniques

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    Aviation binary phase shift keying (A-BPSK) is described and simulated performance results are given that demonstrate robust performance in the presence of hardlimiting amplifiers. The performance of coherently-detected A-BPSK with rate 1/2 convolutional coding are given. The performance loss due to the Rician fading was shown to be less than 1 dB over the simulated range. A partially coherent detection scheme that does not require carrier phase recovery was described. This scheme exhibits similiar performance to coherent detection, at high bit error rates, while it is superior at lower bit error rates

    OSI-compatible protocols for mobile-satellite communications: The AMSS experience

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    The protocol structure of the international aeronautical mobile satellite service (AMSS) is reviewed with emphasis on those aspects of protocol performance, validation, and conformance which are peculiar to mobile services. This is in part an analysis of what can be learned from the AMSS experience with protocols which is relevant to the design of other mobile satellite data networks, e.g., land mobile

    Systems validation: application to statistical programs

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    BACKGROUND: In 2003, the United States Food and Drug Administration (FDA) released a guidance document on the scope of "Part 11" enforcement. In this guidance document, the FDA indicates an expectation of a risk-based approach to determining which systems should undergo validation. Since statistical programs manage and manipulate raw data, their implementation should be critically reviewed to determine whether or not they should undergo validation. However, the concepts of validation are not often discussed in biostatistics curriculum. DISCUSSION: This paper summarizes a "Plan, Do, Say" approach to validation that can be incorporated into statistical training so that biostatisticians can understand and implement validation principles in their research. SUMMARY: Validation is a process that requires dedicated attention. The process of validation can be easily understood in the context of the scientific method

    Performance of concatenated Reed-Solomon trellis-coded modulation over Rician fading channels

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    A concatenated coding scheme for providing very reliable data over mobile-satellite channels at power levels similar to those used for vocoded speech is described. The outer code is a shorter Reed-Solomon code which provides error detection as well as error correction capabilities. The inner code is a 1-D 8-state trellis code applied independently to both the inphase and quadrature channels. To achieve the full error correction potential of this inner code, the code symbols are multiplexed with a pilot sequence which is used to provide dynamic channel estimation and coherent detection. The implementation structure of this scheme is discussed and its performance is estimated

    Scoping review on interventions to improve adherence to reporting guidelines in health research

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    Objectives The goal of this study is to identify, analyse and classify interventions to improve adherence to reporting guidelines in order to obtain a wide picture of how the problem of enhancing the completeness of reporting of biomedical literature has been tackled so far. Design Scoping review. Search strategy We searched the MEDLINE, EMBASE and Cochrane Library databases and conducted a grey literature search for (1) studies evaluating interventions to improve adherence to reporting guidelines in health research and (2) other types of references describing interventions that have been performed or suggested but never evaluated. The characteristics and effect of the evaluated interventions were analysed. Moreover, we explored the rationale of the interventions identified and determined the existing gaps in research on the evaluation of interventions to improve adherence to reporting guidelines. Results 109 references containing 31 interventions (11 evaluated) were included. These were grouped into five categories: (1) training on the use of reporting guidelines, (2) improving understanding, (3) encouraging adherence, (4) checking adherence and providing feedback, and (5) involvement of experts. Additionally, we identified lack of evaluated interventions (1) on training on the use of reporting guidelines and improving their understanding, (2) at early stages of research and (3) after the final acceptance of the manuscript. Conclusions This scoping review identified a wide range of strategies to improve adherence to reporting guidelines that can be taken by different stakeholders. Additional research is needed to assess the effectiveness of many of these interventionsPeer ReviewedPostprint (author's final draft

    A Delphi survey to determine how educational interventions for evidence-based practice should be reported:Stage 2 of the development of a reporting guideline

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    BACKGROUND: Undertaking a Delphi exercise is recommended during the second stage in the development process for a reporting guideline. To continue the development for the Guideline for Reporting Evidence-based practice Educational interventions and Teaching (GREET) a Delphi survey was undertaken to determine the consensus opinion of researchers, journal editors and educators in evidence-based practice (EBP) regarding the information items that should be reported when describing an educational intervention for EBP. METHODS: A four round online Delphi survey was conducted from October 2012 to March 2013. The Delphi panel comprised international researchers, educators and journal editors in EBP. Commencing with an open-ended question, participants were invited to volunteer information considered important when reporting educational interventions for EBP. Over three subsequent rounds participants were invited to rate the importance of each of the Delphi items using an 11 point Likert rating scale (low 0 to 4, moderate 5 to 6, high 7 to 8 and very high >8). Consensus agreement was set a priori as at least 80 per cent participant agreement. Consensus agreement was initially calculated within the four categories of importance (low to very high), prior to these four categories being merged into two (<7 and ≥7). Descriptive statistics for each item were computed including the mean Likert scores, standard deviation (SD), range and median participant scores. Mean absolute deviation from the median (MAD-M) was also calculated as a measure of participant disagreement. RESULTS: Thirty-six experts agreed to participate and 27 (79%) participants completed all four rounds. A total of 76 information items were generated across the four survey rounds. Thirty-nine items (51%) were specific to describing the intervention (as opposed to other elements of study design) and consensus agreement was achieved for two of these items (5%). When the four rating categories were merged into two (<7 and ≥7), 18 intervention items achieved consensus agreement. CONCLUSION: This Delphi survey has identified 39 items for describing an educational intervention for EBP. These Delphi intervention items will provide the groundwork for the subsequent consensus discussion to determine the final inclusion of items in the GREET, the first reporting guideline for educational interventions in EBP

    A systematic review of how studies describe educational interventions for evidence-based practice:Stage 1 of the development of a reporting guideline

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    Abstract Background The aim of this systematic review was to identify which information is included when reporting educational interventions used to facilitate foundational skills and knowledge of evidence-based practice (EBP) training for health professionals. This systematic review comprised the first stage in the three stage development process for a reporting guideline for educational interventions for EBP. Methods The review question was ‘What information has been reported when describing educational interventions targeting foundational evidence-based practice knowledge and skills?’ MEDLINE, Academic Search Premier, ERIC, CINAHL, Scopus, Embase, Informit health, Cochrane Library and Web of Science databases were searched from inception until October - December 2011. Randomised and non-randomised controlled trials reporting original data on educational interventions specific to developing foundational knowledge and skills of evidence-based practice were included. Studies were not appraised for methodological bias, however, reporting frequency and item commonality were compared between a random selection of studies included in the systematic review and a random selection of studies excluded as they were not controlled trials. Twenty-five data items were extracted by two independent reviewers (consistency > 90%). Results Sixty-one studies met the inclusion criteria (n = 29 randomised, n = 32 non-randomised). The most consistently reported items were the learner’s stage of training, professional discipline and the evaluation methods used (100%). The least consistently reported items were the instructor(s) previous teaching experience (n = 8, 13%), and student effort outside face to face contact (n = 1, 2%). Conclusion This systematic review demonstrates inconsistencies in describing educational interventions for EBP in randomised and non-randomised trials. To enable educational interventions to be replicable and comparable, improvements in the reporting for educational interventions for EBP are required. In the absence of a specific reporting guideline, there are a range of items which are reported with variable frequency. Identifying the important items for describing educational interventions for facilitating foundational knowledge and skills in EBP remains to be determined. The findings of this systematic review will be used to inform the next stage in the development of a reporting guideline for educational interventions for EBP

    A Scoping Review of Transitions, Stress, and Adaptation Among Emerging Adults

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    This scoping review examined research on transitions among emerging adults, 18- to 30-year-olds, to identify designs, populations, frameworks, transition types, and transition outcomes. A librarian conducted the search, yielding 2067 articles. Using predefined criteria, teams screened abstracts and reviewed articles, with 82% to 100% interrater agreement. Data from the final 160 articles were placed in evidence tables and summarized. Most frequently, the studies had exploratory-descriptive designs (69%), nondiagnosed samples (58%), no theoretical frameworks (58%), developmental transitions (34%), and health-related behavior outcomes (34%). This transition research is in an early stage of knowledge development and would benefit from further theory development
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