A stroll down Kármán street

The Kármán vortex street is an exquisite flow pattern that can be seen in a variety of flow situations. In this article, we present some of the main features of the phenomenon starting from its interesting history, and also show why it is important in a number of engineering situations. Raghuraman N Govardhan is in the Mechanical Engineering Department at the Indian Institute of Science. He works in the areas of separated flow, fluid-structure interaction and micro-flows. O N Ramesh is at the Department of Aerospace Engineering, Indian Institute of Science, Bangalore. His research interests include transitional and turbulent flows, vortex dynamics and separated flows.     

Systematic academic instruction for students with EBD: the construction and use of a tool for teachers

Educating students with behavioural, emotional and social difficulties requires a thorough systematic approach with the focus on academic instruction. This study addresses the development of a tool, consisting of two questionnaires, for measuring systematic academic instruction. The questionnaires cover the Plan‐Do‐Check‐Act cycle and academic versus behavioural instruction. The questionnaires are both practically oriented as well as theoretically well founded. The reliability turned out to be acceptable (0.76) to high (0.89). Observation scales were developed to determine the validity of both questionnaires. Moderate correlations between questionnaires and observation scales were found (0.31, 0.32). Bland–Altman plots offered us valuable information about the differences between questionnaires and observation scales, supplying us with important issues for further research. It is concluded that the questionnaires might be a valuable tool for assessing teachers' systematic academic instruction.     

The effects of virtual human gesture frequency and reduced video speed on satisfaction and learning outcomes

Educational technology research and development - Educators use various strategies to increase listening comprehension for nonnative English speakers in the classroom and multimedia environments....     

Legitimacy,stratification, and internationalization in global higher education: the case of the International Association of Universities

Tertiary Education and Management - The International Association of Universities (IAU) is the only inclusive global university association, its membership barriers are low, yet few universities...     

Convergence crosscurrents: Analog in the digital and digital in the analog

Abstract

In this Perspective paper we propose a rethink on how we should approach digital and analog news. Although there are literatures that continue to focus on the many and varied characteristics of digital and analog news, we should not consider these as separate, opposing entities. In fact, the intertwining between the digital and the analog of news makes it difficult, if not impossible, to define separately what they are, even if this often is the practice in scholarly debate on news and journalism in new media. What we argue in this paper is that today, in opposition to binary definitions, it would be much more revealing, and also connected to actual media practices, to try to understand how much digital there is in the analog news and, vice versa, how much analog there is in digital news. This approach recognizes three dimensions in media platforms: digital, analog, and, between them, a cross-evolved, digitalized analog present in television, radio, and online newspapers. Recognizing these three dimensions enables us to explore more clearly the implications that the hybridization of digital and analog news has on the overall media system and on the state of news itself.     

Stationary principles and potential functions for nonlinear networks

This paper presents a novel graph theoretic approach for deriving various stationary principles for single-element type nonlinear networks. The concepts of total content, co-content and hybrid content are generalized to that of total parametric content for resistive nonlinear networks containing multivalued elements. The results by Brayton and Moser on potential functions for complete m-ports are generalized to non-complete m-ports in terms of three pseudopotential functions; namely, the pseudo-content, pseudo- co-content and the pseudo-hybrid content. The precise criterion for which each of these pseudo-potential functions reduces to a legitimate potential function is shown to be the unique solvability of an implicit set of equations given explicitly in terms of standard topological matrices. Simple circuit theoretic sufficient conditions are given which require merely the positive-definiteness of the incremental resistance matrix of an auxiliary complete current-controlled p-port and the incremental conductance matrix of an auxiliary complete voltage-controlled q-port. These conditions also guarantee that a non-complete dynamic nonlinear network can be represented by a system of normal form differential equations in terms of a single mixed potential function.     

Role of pump prime in the etiology of cardio-pulmonary bypass associated acidosis

The development of metabolic acidosis during cardio-pulmonary bypass (CPB) is a well recognized but poorly explained phenomenon. It has been hypothesized that it is purely a development after the delivery of pump prime. A retrospective study was conducted at our hospital on 68 patients who underwent elective coronary artery bypass grafting (CABG). Sampling of arterial blood was performed at three time intervals: (T₁) Baseline, prior to induction; (T₂) 5 minutes after initiation of CPB and prior to administration of cardioplegia solution; (T3) during rewarming prior to weaning the patient off CPB. Measurements of Na⁺, K⁺, Cl⁻, pH, pCO₂, HCO₃ ⁻, Base excess, Anion gap, Strong ion difference at each collection point were performed. Results were analyzed in a quantitative manner. On delivery of pump prime, all patients' developed metabolic acidosis. However, it is very important to distinguish the metabolic acidosis as their management varies. Anion gap has been found to be useful in managing peri-operative metabolic acidosis.