44,356 research outputs found
Direct numerical simulation of heat transfer from the stagnation region of a heated cylinder affected by an impinging wake
No full textCopyright © 2011 Cambridge University Press.The effect of an incoming wake on the flow around and heat transfer from the stagnation region of a circular cylinder was studied using direct numerical simulations (DNSs). Four simulations were carried out at a Reynolds number (based on free-stream velocity and cylinder diameter D) of Re = 13200: one two-dimensional (baseline) simulation and three three-dimensional simulations. The three-dimensional simulations comprised a baseline simulation with a uniform incoming velocity field, a simulation in which realistic wake data - generated in a separate precursor DNS - were introduced at the inflow plane and, finally, a simulation in which the turbulent fluctuations were removed from the incoming wake in order to study the effect of the mean velocity deficit on the heat transfer in the stagnation region. In the simulation with realistic wake data, the incoming wake still exhibited the characteristic meandering behaviour of a near-wake. When approaching the regions immediately above and below the stagnation line of the cylinder, the vortical structures from the wake were found to be significantly stretched by the strongly accelerating wall-parallel (circumferential) flow into elongated vortex tubes that became increasingly aligned with the direction of flow. As the elongated streamwise vortical structures impinge on the stagnation region, on one side they transport cool fluid towards the heated cylinder, while on the other side hot fluid is transported away from the cylinder towards the free stream, thereby increasing the heat transfer. The DNS results are compared with various semi-empirical correlations for predicting the augmentation of heat transfer due to free-stream turbulence.German Research Foundatio
Towards a New Catholic Church in Advanced Modernity: Transformations, Visions, Tensions, red. S. Hellemans, J. Wissink, Zürich−Berlin 2012, ss. 280, Tilburg Theological Studies, t. 5.
No full textRecenzja książki: Towards a New Catholic Church in Advanced Modernity: Transformations, Visions, Tensions, red. S. Hellemans, J. Wissink, Zürich−Berlin 2012, ss. 280, Tilburg Theological Studies, t. 5
O pułapce „skojarzeniowej” w humanistyce. (Na marginesie uroszczenia S. Gałkowskiego w jego próbie „logicznej” wykładni Znanieckiego)
No full textAutor polemiki we wstępie wskazuje na zjawisko "reductio ad absurdum" koncepcji Znanieckiego w wykładni adresata jego krytyki. Dalej jest zarysowana ogólna perspektywa sprzeciwu wobec podejścia Stanisława Gałkowskiego. Przedstawiono także krytycyzm i pochwały wobec Znanieckiego ze strony autora polemiki. W tekście wskazuje się na pułapkę czytania epistemicznego jako etyczne nadużycie logiki. Wreszcie, zamiast zakończenia, mówi się o traktowaniu tradycji myśli humanistycznej i uczula na błędy interpretacyjne popełnione przez krytykowanego autora. Główny błąd polega na skojarzeniach czytelnika blokujących mu głębszy dostęp do znaczenia czytanej koncepcji.In his introduction the author of this polemic indicates the phenomenon of "reductio ad absurdum" of Znaniecki's conception in the exegesis of the addressee of this criticism. Next there is an outline sketched concerning the general perspective of disagreement against the approach by S. Gałkowski. There is also outlined criticism and appraisal towards Znaniecki by the author of this polemics. The text illustrates the trap of an epistemic reading as an ethical abuse of logics. Finally instead of a conclusion one is discussing the ways of treatement of the tradition of humanistic reflection and it warns against interpretative errors committed by the criticised author. The basic error is perceived as the result of domination of application of harmful associations of the leader blocking the way to deeper sense of the conception
Direct numerical simulations of transition in a compressor cascade: The influence of free-stream turbulence
No full textCopyright © Cambridge University Press 2010.The flow through a compressor passage without and with incoming free-stream grid turbulence is simulated. At moderate Reynolds number, laminar-to-turbulence transition can take place on both sides of the aerofoil, but proceeds in distinctly different manners. The direct numerical simulations (DNS) of this flow reveal the mechanics of breakdown to turbulence on both surfaces of the blade. The pressure surface boundary layer undergoes laminar separation in the absence of free-stream disturbances. When exposed to free-stream forcing, the boundary layer remains attached due to transition to turbulence upstream of the laminar separation point. Three types of breakdowns are observed; they combine characteristics of natural and bypass transition. In particular, instability waves, which trace back to discrete modes of the base flow, can be observed, but their development is not independent of the Klebanoff distortions that are caused by free-stream turbulent forcing. At a higher turbulence intensity, the transition mechanism shifts to a purely bypass scenario. Unlike the pressure side, the suction surface boundary layer separates independent of the free-stream condition, be it laminar or a moderate free-stream turbulence of intensity Tu ~ 3%. Upstream of the separation, the amplification of the Klebanoff distortions is suppressed in the favourable pressure gradient (FPG) region. This suppression is in agreement with simulations of constant pressure gradient boundary layers. FPG is normally stabilizing with respect to bypass transition to turbulence, but is, thereby, unfavourable with respect to separation. Downstream of the FPG section, a strong adverse pressure gradient (APG) on the suction surface of the blade causes the laminar boundary layer to separate. The separation surface is modulated in the instantaneous fields of the Klebanoff distortion inside the shear layer, which consists of forward and backward jet-like perturbations. Separation is followed by breakdown to turbulence and reattachment. As the free-stream turbulence intensity is increased, Tu ~ 6.5%, transitional turbulent patches are initiated, and interact with the downstream separated flow, causing local attachment. The calming effect, or delayed re-establishment of the boundary layer separation, is observed in the wake of the turbulent events.Air Force Office of Scientific Researc
Heat transfer from the stagnation area of a heated cylinder at Re(D) = 140,000 affected by free-stream turbulence
No full textThis is the post-print version of the final paper published in International Journal of Heat and Mass Transfer. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2011 Elsevier B.V.The effect of free-stream grid-turbulence on the flow around and heat transfer from the stagnation region of a circular cylinder was studied using direct numerical simulations (DNS). Simulations with and without free-stream fluctuations were carried out at a Reynolds number of Re(D) = 140,000 (based on the inflow velocity and the cylinder diameter D), which is in the higher subcritical range. A splitter plate was introduced behind the cylinder to counteract the formation of a vortex street. To resolve the flow up to 746.5 million grid points were employed. Compared to the fully laminar simulation, the addition of Tu = 30% grid turbulence at the inflow plane was found to lead to an increase in heat transfer at the stagnation line of the cylinder of 66%. A very good agreement was obtained with the correlations of Dullenkopf and Mayle [K. Dullenkopf, R. Mayle, The effects of incident turbulence and moving wakes on laminar heat transfer in gas turbines, ASME J. Turbomach. 116 (1994) 23–28; K. Dullenkopf, R. Mayle, An account of free-stream-turbulence length scale on laminar heat transfer, ASME J. Turbomach. 117 (1995) 401–406].The German Research Foundatio
Seeing the world anew : the radical vision of Martin Waldseemüller's 1507 & 1516 world maps /
No full text9781929154470 (ISBN). 192915447X (ISBN). First edition 2012. Accompanied by 2 foldeds map in front and back pockets: 1507 map -- 1516 map.; Includes bibliographical references: pages 98-107.; Maps from pockets also available online http://nla.gov.au/nla.map-vn6254227; Original version of the 1507 map: Universalis cosmographiae secundum Ptholomaei traditionem et Americi Vespucii alioru que lustrationes. [St. Dié, France? : s.n., 1507]; Original version of the 1516 map: Carta marina, navigatoria Portugallen, navigationes atque tocius cogniti orbis terre marisque formam naturamq[u]e situs et terminos nostris temporibus recognitos et ab antiquorum traditione differentes eciam quor[um] vetusti non meminerunt auctores hec generaliter indicat / consumatum est in oppido S. Deodati compositione et digestione Martini Waldseemuller Ilacomili. [St. Dié, France? : s.n., 1516]. Prologue: In a Renaissance Vision, a Glimpse of the Modern / John W. Hessler -- "An island surrounded on all sides by sea" : The World Map, 1507 / John W. Hessler -- "Land of Cuba, part of Asia" : The Carta marina, 1516 / Chet Van Duzer -- Epilogue: A Renaissance That Resonates Still / John W. Hessler -- Notes -- Afterword / Ralph E. Ehrenberg -- About the authors -- Acknowledgments -- The Maps: The 1507 World Map, 12 sheets, with commentary -- Composite: front pocket -- The 1516 Carta marina, 13 sheets, with commentary -- Composite: back pocket
Rola Uniwersytetu Otwartego w nowoczesnej edukacji na odległość w promocji zrównoważonego rozwoju w Indiach i Polsce
No full textThe paper attempts to analyse, as to how distance education mechanisms can be effectually used for sustainability in areas of the human environment, health and management of the natural resources. Short review of methodological experiences in education of knowledge-based society for common action with experts for promotion sustainable development is based on over 20 years activity in this field of the AGH Open University and the Open Seminars on Sustainable Development and ca. 40 years of informal, problem-solving education in linkage with interdisciplinary case studies. Further this model will be sustainable in terms of clean technology used, for the benefit of the human environment and better quality of life. The concept is related to long-term international cooperation of the Polish author (e.g. from 1983 with Indian scientists) on human ecology, medical elementology, ecotoxicology and biotechnology as well as future requirements of the National Open University in India.Artykuł stanowi próbę oceny możliwości zastosowania mechanizmów edukacji na odległość w celu skutecznej promocji zrównoważonych działań w dziedzinach środowiska człowieka, zdrowia i oszczędnej gospodarki zasobami przyrody. Zwięzły przegląd doświadczeń metodycznych w zakresie edukacji społeczeństwa opartego na wiedzy nawiązuje do ponad 20-letniej działalności w tym zakresie Uniwersytetu Otwartego AGH oraz Otwartego Seminarium nt. Zrównoważonego Rozwoju, a także do 40-letniej nieformalnej edukacji ukierunkowanej na rozwiązywanie problemów w powiązaniu z badaniami interdyscyplinarnymi. Model ten służy zrównoważonemu rozwojowi, ponieważ promuje technologie proekologiczne pożyteczne dla środowiska człowieka i wpływające na poprawę jakości życia. Nawiązuje on też do wieloletniej międzynarodowej współpracy polskiego współautora (m.in. od 1983 r. z indyjskimi naukowcami) w zakresie ekologii człowieka, elementologii medycznej, ekotoksykologii i biotechnologii oraz potrzeb rozwojowych Narodowego Uniwersytetu Otwartego w Indiach
Author Correction: Establishment and equilibrium levels of deleterious mutations in large populations (Scientific Reports, (2019), 9, 1, (10384), 10.1038/s41598-019-46803-7)
No full textThe original version of this Article contained errors. Affiliations 1 and 2 were reversed. Secondly, Affiliation 7 was incorrectly given as ‘Institute for Cellular and Molecular Medicine, Department of Immunology, and SAMRC Extramural Unit for Stem Cell Research and Therapy, Faculty of Health Sciences, University of Pretoria, Pretoria, 0084, South Africa’. Thirdly, an affiliation was omitted for the author Michael S. Pepper, which is now listed as Affiliation 8. Fourthly, Affiliation 1 was omitted for the author Johan W. Viljoen. Finally, Augustinus J. van Zyl was incorrectly affiliated with ‘Institute for Maternal and Child Health, IRCCS ‘Burlo Garofolo’, Trieste, Italy.’ The correct author affiliations are listed below: Affiliation 1: Department of Electrical, Electronic and Computer Engineering, EBIT, University of Pretoria, Pretoria 0028, South Africa Johan W. Viljoen and J. Pieter de Villiers Affiliation 2: Development, Research and Technology Department, Hensoldt Optronics, Centu..
Author neologisms in the novel "Rzeczy uprzyjemniające. Utopia" by T. Boldak-Janovska
No full textThe purpose of this article is an analysis of author neologisms extracted from the novel "Rzeczy uprzyjemniające. Utopia" by T. Boldak-Janovska – writer, although living in Olsztyn, belonging to the Polish-Belarusian border. The object of research was elected not by accident: for a few years the novel attracts the attention of readers and critics. For the purposes of this analysis were selected 186 neologisms, mostly nouns and verbs, most of whom are motivated formations. The most numerous are the names of animals, birds, reptile and fish, names of plants, trees, shrubs, names of everyday objects. Author neologisms constitute an indispensable component of the Polish vocabulary. They are understandable for the users through the context and through the semantic link to the radial network to which they [email protected]. Bołdak-Janowska, 2009, Rzeczy uprzyjemniające. Utopia, Olsztyn.Buttler D., 1962, Neologizm i terminy pokrewne, „Poradnik Językowy” nr 5, s. 239–244.Bołdak-Janowska T., 2012, Szkic na Trialog 2012, „Jak daleko stąd, jak blisko”, czyli gdzie?, http://issuu.com/tamarabejot/docs/jak daleko/1, online, [8.10.
2014].Chłosta-Zielonka J., 2013, Najnowsza proza olsztyńskich twórców. Rekonesans, „Prace Literaturoznawcze UniwersytetuWarmińsko-Mazurskiego” t. 1, Olsztyn, s. 229–239.Jadacka H., 2001, System słowotwórczy polszczyzny (1945–2000), Warszawa.Kwietniowa W., 1973, O neologizmach stylu artystycznego, „Polonistyka” nr 5, s. 9–17. Polska Biografia Literacka PAN, 2012, www.pbl.ibl.poznan.pl, online, [8.10.2014]Sękowska E., 2012, Neologizmy słowotwórcze we współczesnej polszczyźnie (wybrane tendencje), [w:] Eslavistica Complutense, Warszawa, s. 97–103.Skubalanka T., 1990, Problematyka gramatyczno-stylistyczna neologizmu, „Studia Linguistica Polono-Slovaca” nr 3, s. 31–37.Smółkowa T., 1997,Metodologiczne aspekty opisu współczesnych neologizmów i neosemantyzmów polskich, [w:] Leksyka słowiańska na warsztacie językoznawcy, red. H. Popowska-Taborska, Warszawa.Smółkowa T., 2001, Neologizmy we współczesnej leksyce polskiej, Kraków.Waszakowa K., 1998, Neologizmy tekstowe w świetle ram interpretacyjnych, [w:] Tekst. Analizy i interpretacje, Lublin, s. 21–33.Waszakowa K., 2007, Wariantywne postaci neologizmów w świetle adaptacyjnej funkcji słowotwórstwa, „Prace Filologiczne Uniwersytetu Warszawskiego” t. LIII, Warszawa, s. 691–700.299-31
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