105,970 research outputs found
Performance of a Vertical Axis Wind Turbine under Accelerating and Decelerating Flows
Get PDFRapid increase in global energy requirements has resulted in considerable attention towards energy generation from the renewable energy sources. In order to meet renewable energy targets, harnessing energy from all available resources including
those from urban environment is required. Vertical Axis Wind Turbines (VAWTs) are seen as a potential way of utilising urban energy sources. Most of the research on the wind turbines constitutes condition monitoring and performance optimisation of VAWTs under a constant velocity of air where the transient effects have not been accounted. The inconsistent behaviour of the wind may change the nature of the flow field around the VAWT which could decrease its life cycle. This study is an attempt to use Computational Fluid Dynamic’s techniques to study and analyse the performance of a wind turbine under accelerating and
decelerating air inlet velocity. The performance of a VAWT is monitored under an accelerated and decelerated gust of the value 1.09m/s² characterised by change in velocity from 4m/sec to 10m/sec. The instantaneous torque output varies significantly when a gust of air is applied to the turbine. Furthermore the torque outputs during accelerating and decelerating flows vary, highlighting the effect of transient phenomena. This abrupt change in the instantaneous torque output of the turbine may give rise to highly transient loads on the turbine’s structure which may induce heavy stresses on the turbine leading to structural failure. It has been shown that CFD can be used as an effective tool to predict the performance outputs of a VAWT under varying flow
conditions
Comparing Cigarette-Cue Attentional Bias Between People With HIV/AIDS and People With Opioid Use Disorder Who Smoke
No full textThis dataset comprises fixation time (FT) on cigarette cues (S) and neutral cues (N), measured with an eye tracker. Pairs of cues were presented for 1000 milliseconds and 2000 milliseconds. Cigarette cues encompassed either people smoking cigarettes or cigarette paraphernalia. Participants encompassed two populations - people living with HIV who smoke and people with opioid use disorder who smoke
Approximating Sparsest Cut in Low Rank Graphs via Embeddings from Approximately Low Dimensional Spaces
No full textWe consider the problem of embedding a finite set of points x_1, ... , x_n in R^d that satisfy l_2^2 triangle inequalities into l_1, when the points are approximately low-dimensional. Goemans (unpublished, appears in a work of Magen and Moharammi (2008) ) showed that such points residing in exactly d dimensions can be embedded into l_1 with distortion at most sqrt{d}. We prove the following robust analogue of this statement: if there exists a r-dimensional subspace Pi such that the projections onto this subspace satisfy sum_{i,j in [n]} norm{Pi x_i - Pi x_j}_2^2 >= Omega(1) * sum_{i,j \in [n]} norm{x_i - x_j}_2^2, then there is an embedding of the points into l_1 with O(sqrt{r}) average distortion. A consequence of this result is that the integrality gap of the well-known Goemans-Linial SDP relaxation for the Uniform Sparsest Cut problem is O(sqrt{r}) on graphs G whose r-th smallest normalized eigenvalue of the Laplacian satisfies lambda_r(G)/n >= Omega(1)*Phi_{SDP}(G). Our result improves upon the previously known bound of O(r) on the average distortion, and the integrality gap of the Goemans-Linial SDP under the same preconditions, proven in [Deshpande and Venkat, 2014], and [Deshpande, Harsha and Venkat 2016]
Bibliographie Hilarion G. Petzold 1958 – 2009 mit Anhang als Einführung
No full textDieses Archiv enthält die Gesamtbibliographie der Werke des Autors nebst einiger Texte „Über H. G. Petzold“ im Schlussteil der Bibliographie sowie einen Anhang mit einer Einführung in die Architektur des Werkes in seinem wissenslogischen Aufbau als Ausarbeitung seines „Tree of Science Modells“ (2007).This archive contains the complete bibliography of the author and some texts about H. G. Petzold, moreover an epilogue with an introduction to the architecture of the works in its epistemological structure and composition and as an elaborations of Petzold’s „Tree of Science Modell (2007).https://www.fpi-publikation.de/polyloge/01-2009-petzold-h-g-gesamtbibliographie-h-g-petzold-1958-2009-updating-november2009/peerReviewedpublishedVersio
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Teachers’ and Students' Attitudes Towards Traditional and Computer Assisted Blended Teaching and Learning Processes in Mechanical Engineering Subjects Area
No full textThe effectiveness of traditional teaching-learning process in Computer Aided Design (CAD), Computer Aided Manufacturing CAM and Computer Numerical control CNC (CAD-CAM-CNC) module has been evaluated against recently developed two blended teaching learning models. The blended learning systems have been developed by integrating computer assisted instructions with the traditional teaching learning system. This study in particular reports teachers’ and students’ views about various facets of teaching and learning process under different modes. It has been see that blended learning modes find better acceptance amongst teachers and students as co mpared to traditional teaching mode
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3346: Samuel G. Freedman, author, 2013
No full textPhotograph of author Samuel G. Freedman, at NT Daily Slash meeting in the Mayborn School of Journalism at UNT
The Right to Strike under the United States Constitution: Theory, Practice, and Possible Implications for Canada
No full textAnswering critics of the Canadian Supreme Court's judgment in B.C. Health, the author argues that the Court laid the foundation for a principled and durable doctrine protecting constitutional labour rights, one that goes directly to the heart of the matter — the inequality of workers’ power in the employment relation. In the author’s view, two paths could lead from B.C. Health to the recognition of Charter protec- tion for a right to strike: one that treats the right as an accessory to col- lective bargaining, and one that upholds the right directly on the basis of the Charter values of equality and participation. The author supports the latter approach, contending that constitutional rights should be defined in relation to fundamental values, in a way that is not contingent on time-bound or fact-sensitive assessments about the role of strikes within a particular collective bargaining regime. Although a Charter right to strike may involve the courts in difficult choices about when to defer to legislative policy decisions, and courts may lack the institutional capac- ity to deal effectively with labour law issues, the author points out that judges can look to ILO standards for expert guidance. Noting that the U.S. experience in this area might be of considerable use to Canadians, the author concludes by providing an overview of American case law concerning a constitutional right to strike.Peer reviewe
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