9,295 research outputs found
Performance of the image statistics decoder in conjunction with the Goldstone-VLA array
During Voyager's Neptune encounter, the National Radio Astronomy Observatory's Very Large Array (VLA) will be arrayed with Goldstone antennas to receive the transmitted telemetry data from the spacecraft. The telemetry signal from the VLA will drop out periodically, resulting in a periodic drop in the received signal-to-noise ratio (SNR). The Image Statistics Decoder (ISD), which assumes a correlation between pixels, can improve the bit error rate (BER) for images during these dropout periods. Simulation results have shown that the ISD, in conjunction with the Goldstone-VLA array can provide a 3-dB gain for uncompressed images at a BER of 5.0 x 10(exp -3)
Galileo, Copernicus, and the Tides
Galileo’s endorsement of Copernicus’ helio-centric theory of the strucÂture of the universe presents a good test of two popular views about scientific methodology: (1) scientists prefer a theory which can solve problems it was not invented to solve. And (2) scientists prefer a theory which can solve problems not solved by its predecessor. Let us call (1) the Accidental Thesis (AL) and (2) the Predecessor Thesis (PL). Where Galileo is concerned, both AL and PL are supportable in varying degrees depending on some qualifications. The story shows that the problem Galileo sought to solve, the ebbing and flowing of the seas, i.e. the tides, required the motions of the earth dictated by Copernicus’ theory but denied in Ptolemaic theory. Before dealing with the specific theses, two issues need to be addressed. (1) Why this particular case was picked to illuminate the issue of theory appraisal, and (2) the status of CoperÂnicus’ view. Following the discussion of these issues we will examine the development of Galileo’s account of the tides. This will leave us with our final question: why did Galileo choose the particular theory of the tides he defended
The Capital Market as a Growth Engine
Internationaler Finanzmarkt, Wirtschaftswachstum, Markteffizienz, International financial market, Economic growth, Market efficiency
Frame synchronization performance and analysis
The analysis used to generate the theoretical models showing the performance of the frame synchronizer is described for various frame lengths and marker lengths at various signal to noise ratios and bit error tolerances
Economic Evaluation in Global Perspective: A Bibliometric Analysis of the Recent Literature.
We present a bibliometric analysis of recently published full economic evaluations of health interventions and reflect critically on the implications of our findings for this growing field. We created a database drawing on 14 health, economic, and/or general literature databases for articles published between 1 January 2012 and 3 May 2014 and identified 2844 economic evaluations meeting our criteria. We present findings regarding the sensitivity, specificity, and added value of searches in the different databases. We examine the distribution of publications between countries, regions, and health areas studied and compare the relative volume of research with disease burden. We analyse authors' country and institutional affiliations, journals and journal type, language, and type of economic evaluation conducted. More than 1200 economic evaluations were published annually, of which 4% addressed low-income countries, 4% lower-middle-income countries, 14% upper-middle-income countries, and 83% high-income countries. Across country income levels, 53, 54, 86, and 100% of articles, respectively, included an author based in a country within the income level studied. Biomedical journals published 74% of economic evaluations. The volume of research across health areas correlates more closely with disease burden in high-income than in low-income and middle-income countries. Our findings provide an empirical basis for further study on methods, research prioritization, and capacity development in health economic evaluation
Economic Evaluation in Global Perspective: A Bibliometric Analysis of the Recent Literature.
We present a bibliometric analysis of recently published full economic evaluations of health interventions and reflect critically on the implications of our findings for this growing field. We created a database drawing on 14 health, economic, and/or general literature databases for articles published between 1 January 2012 and 3 May 2014 and identified 2844 economic evaluations meeting our criteria. We present findings regarding the sensitivity, specificity, and added value of searches in the different databases. We examine the distribution of publications between countries, regions, and health areas studied and compare the relative volume of research with disease burden. We analyse authors' country and institutional affiliations, journals and journal type, language, and type of economic evaluation conducted. More than 1200 economic evaluations were published annually, of which 4% addressed low-income countries, 4% lower-middle-income countries, 14% upper-middle-income countries, and 83% high-income countries. Across country income levels, 53, 54, 86, and 100% of articles, respectively, included an author based in a country within the income level studied. Biomedical journals published 74% of economic evaluations. The volume of research across health areas correlates more closely with disease burden in high-income than in low-income and middle-income countries. Our findings provide an empirical basis for further study on methods, research prioritization, and capacity development in health economic evaluation
Assimilation Time As A Factor Of Performance: Impact On A New Generation Of Students
This paper explores the issue of whether assimilation time has any bearing on the performance of students. Assimilation time is defined as the number of times during the week that a class meets. This study examined whether students would perform better in a 50-minute class that met three days a week versus a 75-minute class that met just two days a week. Assimilation time did make a difference (t-test, p = .0693). High-attending students, that is students that attend class more that ninety percent of the time, performed better with more assimilation time that high-attending students in sections with less assimilation time However, for “medium-attending” students there was no difference whether students attended class in a 50-minute class that met three days a week or a 75-minute class that met just two days a week
Technical and operational difficulties experienced on the UKOOA Foula project, June to December 1977
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