4,310 research outputs found
On using Directional Information for Parameter Space Decomposition in Ellipse Detection
No full textIn this paper we use the parametric polar representation to extend the application of edge directional information from circle to ellipse extraction. As a result we obtain a mapping which decomposes the parameter space required for ellipse extraction into two independent sub-spaces and one final histogram accumulator. The mapping includes the tangent of the angle of the first and second directional derivatives. These tangents are computed by considering edge direction at two border points. We show that the use of gradient information for parameter space decomposition avoids the intensive point labelling imposed by geometric constraints used by other approaches
Adaptive Neural Network Imaging in Medical Systems
No full textRecent technological advances in medicine has facilitated the development of sophisticated equipment enabling the better delivery of health care services. In parallel, artificial neural networks have emerged as promising tools for the application and implementation of intelligent systems. The aim of this paper is to provide a snapshot of the application of neural network systems in medical imaging. The paper highlights neural network applications in the analysis of cervicovaginal smears, mammography, microscopy, ultrasound imaging, and lesion placement in pallidotomy. It is anticipated that the application of neural network systems in medicine will provide the framework for the development of emerging medical systems, enabling the better delivery of health care
Large-scale patterns in turbulent Rayleigh-Bénard convection in very large aspect ratio cells
No full textLarge-scale patterns, which are well-known from the spiral defect chaos regime of thermal convection at Rayleigh numbers Ra 105. They are uncovered when the turbulent fields are averaged in time and turbulent fluctuations are thus removed. We apply the Boussinesq closure to calculate turbulent viscosities and diffusivities, respectively. The resulting turbulent Rayleigh number Ra_, that describes the convection of the mean patterns, is indeed in the spiral defect chaos range. Interestingly, the turbulent Prandtl numbers are smaller than one with 0:2 _ Pr_ _ 0:4 for Prandtl numbers 0:7 _ Pr _ 10. Finally, we demonstrate that these mean flow patterns are robust to an additional finite-amplitude side wall-forcing when the level of turbulent fluctuations in the flow is sufficiently high
Reynolds number effect on 3D turbulent offset jet reattaching to a free surface
No full textExperimental study was carried out to investigate the effect of Reynolds number on 3D offset jet reattaching to above free surface. Sharp edged square nozzle was used to produce the jets, and the measurements were performed at the following six different Reynolds numbers: 2300, 3700, 5100, 7900, 10300 and 11900. Detailed velocity measurements were made in the symmetry plane. From the PIV data, the mean velocity and turbulence statistics were obtained to study the effects of Reynolds number on the salient features of the jet flow. Preliminary results on streamwise mean velocity decay along the nozzle centerline, contours of streamwise mean velocity and Reynolds shear stress are presented herein
Novel algorithms for the accurate, efficient, and parallel computation of multidimensional, regional discrete Fourier transforms
No full textThe Benefits of Being Economics Professor A (and not Z)
No full textAlphabetic name ordering on multi-authored academic papers, which is the convention in the economics discipline and various other disciplines, is to the advantage of people whose last name initials are placed early in the alphabet. As it turns out, Professor A, who has been a first author more often than Professor Z, will have published more articles and experienced afaster growth rate over the course of her career as a result of reputation and visibility. Moreover, authors know that name ordering matters and indeed take ordering seriously: Several characteristics of an author group composition determine the decision to deviate from the default alphabetic name order to a significant extent.performance measurement, incentives, economists, name ordering
<i>Entrenchment, wealth, power, and the constitution of democratic societies</i> by Paul Starr
No full textEntrenchment, Wealth, Power, and the Constitution of Democratic Societies, by Paul Starr, New Haven, CT: Yale University Press. 2019. 280 pages, hardcover.Why should we, as Management scholars and educators, care about a book on political diagnosis? The answer is twofold. First, the calibre of the author (Paul Starr), an awardee of both Bancroft and Pulitzer Prizes, a former policy advisor to the Clinton administration, and the author of The Transformation of American Medicine (1982), a book with a profound impact on American policy circles. Second, the core concept (entrenchment) of the book, and its potential to advance the process of institutional development, and the ways in which we can reform and change our institutions to better meet the current and pressing needs of the many, rather than preserve the unequal privileges of a few. In light of the geopolitical, social, and environmental pressures we see currently rising across the world (George, Howard-Grenville, Joshi & Tihanyi, 2016; Howard-Grenville, Buckle, Hoskins & George, 2014) there is no better time to examine whether and how we can address some of these grand challenges by reforming and improving our institutions
M.S. Kutorga and V.M. Vedrov: Conflict of Teacher and Student
No full textВ статье рассматривается конфликт между М.С. Куторгой и его учеником В.М. Ведровым. Исследуются причины конфликта, а также то влияние, которое он оказал на дальнейшую научную карьеру ученика. This article discusses the conflict between M.S. Kutorga and his student V.M. Vedrov. The author investigates the causes of the conflict and its impact on academic career V.M. Vedrov
Wireless Medical Ultrasound Video Transmission Through Noisy Channels
No full textRecent advances in video compression such as the current state-of-the-art H.264/AVC standard in conjunction with increasingly available bitrate through new technologies like 3G, and WiMax have brought mobile health (m-Health) healthcare systems and services closer to reality. Despite this momentum towards m-Health systems and especially e-Emergency systems, wireless channels remain error prone, while the absence of objective quality metrics limits the ability of providing medical video of adequate diagnostic quality at a required bitrate. In this paper we investigate different encoding schemes and loss rates in medical ultrasound video transmission and come to conclusions involving efficiency, the trade-off between bitrate and quality, while we highlight the relationship linking video quality and the error ratio of corrupted P and B frames. More specifically, we investigate IPPP, IBPBP and IBBPBBP coding structures under packet loss rates of 2%, 5%, 8% and 10% and derive that the latter attains higher SNR ratings in all tested cases. A preliminary clinical evaluation shows that for SNR ratings higher than 30 db, video diagnostic quality may be adequate, while above 30.5 db the diagnostic information available in the reconstructed ultrasound video is close to that of the original
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