633 research outputs found

    Programmable rate modem utilizing digital signal processing techniques

    Get PDF
    The engineering development study to follow was written to address the need for a Programmable Rate Digital Satellite Modem capable of supporting both burst and continuous transmission modes with either binary phase shift keying (BPSK) or quadrature phase shift keying (QPSK) modulation. The preferred implementation technique is an all digital one which utilizes as much digital signal processing (DSP) as possible. Here design tradeoffs in each portion of the modulator and demodulator subsystem are outlined, and viable circuit approaches which are easily repeatable, have low implementation losses and have low production costs are identified. The research involved for this study was divided into nine technical papers, each addressing a significant region of concern in a variable rate modem design. Trivial portions and basic support logic designs surrounding the nine major modem blocks were omitted. In brief, the nine topic areas were: (1) Transmit Data Filtering; (2) Transmit Clock Generation; (3) Carrier Synthesizer; (4) Receive AGC; (5) Receive Data Filtering; (6) RF Oscillator Phase Noise; (7) Receive Carrier Selectivity; (8) Carrier Recovery; and (9) Timing Recovery

    A Modified Underwater Weighing Method Without Complete Immersion

    Get PDF
    This study was designed to examine the validity of a modified underwater weighing method for measuring human body volume (BV) that does not require head submersion (MUW). Results were compared with those obtained by the underwater weighing method (UW). The true head volume was calculated from the difference in BV, with and without head submersion. Stepwise regression analysis provided an equation to predict the head volume (HV) from the head girth (HG), the head length (HL), the head breadth (HB), the neck girth (NG), the face length I (FLI), the face length II (FLII), and the cheek girth. The equation for males was HV=0.185^*(HG) +0.122^*(FLII) -8.925, r^2=0.678, SEE=0.216. The equation for females was HV=0.131^*(HG) -0.026^*(NG) +0.112^*(FLI) -6.760, r^2=0.747, SEE=0.154. Cross-validation of predicted HV showed that the correlation coefficients were r=0.759, SEE=0.193 and r=0.749, SEE=0.193, for males and females respectively. Correlation coefficients and SEE between MUW and MW for body volume and % body fat were r=1.000, SEE=0.207 and r=0.983, SEE=1.339 for males and r=1.000, SEE=0.196 and r=0.946, SEE=1.915 for females. It can be concluded that this new method offers promising possibilities for future research with people who are unable to submerge their heads

    Chronic hepatitis infection is associated with extrahepatic cancer development: a nationwide population-based study in Taiwan

    Get PDF
    This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the major causes of chronic hepatitis infection (CHI). This longitudinal cohort study investigated the association of CHI with hepatic and extrahepatic cancer development in Taiwan. Methods: Patients with HBV infection and HCV infection were identified from the Taiwan National Health Insurance Research Database. A Cox proportional hazard model was used to calculate hazard ratios (HRs) and 95 % confidence intervals (CIs) for determining the association between CHI and cancer development. Results: The patients with HBV infection exhibited an increased risk of colorectal cancer (HR: 1.36, 95 % CI: 1.09–1.70), liver cancer (HR: 21.47, 95 % CI: 18.0–25.6), gallbladder and extrahepatic bile duct cancer (HR: 2.05, 95 % CI: 1.07–3.91), pancreatic cancer (HR: 2.61, 95 % CI: 1.47–4.61), kidney cancer (HR: 1.72, 95 % CI: 1.10–2.68), ovarian cancer (HR: 2.31, 95 % CI: 1.21–4.39), and non-Hodgkin’s lymphoma (HR: 2.10, 95 % CI: 1.25–3.52). The patients with HCV infection exhibited an increased risk of liver cancer (HR: 25.10, 95 % CI: 20.9–30.2), gallbladder and extrahepatic bile duct cancer (HR: 2.60, 95 % CI: 1.42–4.73), ovarian cancer (HR: 5.15, 95 % CI: 1.98–13.4), and non-Hodgkin’s lymphoma (HR: 2.30, 95 % CI: 1.34–3.96). Conclusion: The present population-based study revealed that in addition to its association with primary liver cancer, CHI is associated with an increased risk of extrahepatic cancer

    Prevalence of Novel Candidate Sjogren Syndrome Autoantibodies in the Dry Eye Assessment and Management (DREAM) Study.

    Get PDF
    PurposeTo evaluate the prevalence of novel candidate Sjogren syndrome (SS) autoantibodies [salivary protein-1 (SP-1), parotid secretory protein, carbonic anhydrase 6] in the DRy Eye Assessment and Management (DREAM) cohort, a study evaluating the effectiveness of omega-3 fatty acid supplements for the treatment of dry eye.MethodsParticipants underwent ocular surface examinations and serological testing for traditional and novel SS autoantibodies. Dry eye assessment and management participants were categorized into the following 3 groups: 1) no history of SS or other autoimmune diseases and negative traditional SS autoantibodies (n = 352); 2) no history of SS but a history of other autoimmune diseases (n = 66); and 3) those who met the 2012 American College of Rheumatology SS classification criteria (n = 52).ResultsEleven percent had a history of SS, and 6% of those without a history of SS most likely had undiagnosed SS. The SS group had a higher prevalence of SP-1 autoantibodies than the group without SS or other autoimmune diseases (33% vs. 19%; P = 0.02) but had no difference in carbonic anhydrase 6 (P = 0.31) or parotid secretory protein autoantibodies (P = 0.33). Participants who were positive for the traditional autoantibodies alone or positive for both traditional and novel autoantibodies had the highest scores for corneal (P = 0.002) and conjunctival staining (P < 0.001).ConclusionsData from this multicenter, prospective study demonstrated that one of the novel candidate autoantibodies, SP-1, is associated with underlying SS and that novel autoantibodies may be associated with worse ocular surface disease. Future longitudinal studies are needed to evaluate their utility in screening patients with dry eye for SS

    Dynamic p-enrichment schemes for multicomponent reactive flows

    Full text link
    We present a family of p-enrichment schemes. These schemes may be separated into two basic classes: the first, called \emph{fixed tolerance schemes}, rely on setting global scalar tolerances on the local regularity of the solution, and the second, called \emph{dioristic schemes}, rely on time-evolving bounds on the local variation in the solution. Each class of pp-enrichment scheme is further divided into two basic types. The first type (the Type I schemes) enrich along lines of maximal variation, striving to enhance stable solutions in "areas of highest interest." The second type (the Type II schemes) enrich along lines of maximal regularity in order to maximize the stability of the enrichment process. Each of these schemes are tested over a pair of model problems arising in coastal hydrology. The first is a contaminant transport model, which addresses a declinature problem for a contaminant plume with respect to a bay inlet setting. The second is a multicomponent chemically reactive flow model of estuary eutrophication arising in the Gulf of Mexico.Comment: 29 pages, 7 figures, 3 table

    University Students’ Experiences with Hybrid Physical Education Classes During COVID-19: A Qualitative Analysis of 2021 Survey Data

    Get PDF
    P(論文)Educational and Practical Researchdepartmental bulletin pape
    corecore