890 resultados para Couette gap
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Петър Господинов, Добри Данков, Владимир Русинов, Стефан Стефанов - Изследвано е стационарно течение на Кует на разреден газ в случая на въртене на вътрешния цилиндър и неподвижен външен цилиндър чрез използване на DSMC метод и числено решение на уравненията на Навие–Стокс за относително малка (дозвукова) скорост на въртене. Изследвани са различни случаи при промяна на температурата на въртящият се цилиндър и числото на Кнудсен. Целта на изследването е да се установи влиянието на малки скорости на въртене върху макрохарактеристиките – плътността, скоростта и температурата на газа. Установено е добро съвпадение на резултатите получени по двата метода за Kn = 0.02. Получените резултати са важни при решаването на неравнинни, задачи от микрофлуидиката с отчитане на ефектите на кривината. Ключови думи: механика на флуидите, кинетична теория, разреден газ, DSMC.
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Given an n-ary k-valued function f, gap(f) denotes the essential arity gap of f which is the minimal number of essential variables in f which become fictive when identifying any two distinct essential variables in f. In the present paper we study the properties of the symmetric function with non-trivial arity gap (2 ≤ gap(f)). We prove several results concerning decomposition of the symmetric functions with non-trivial arity gap with its minors or subfunctions. We show that all non-empty sets of essential variables in symmetric functions with non-trivial arity gap are separable. ACM Computing Classification System (1998): G.2.0.
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We investigate the operator associating with a function fєLp2π, 1
gap system, as well as an operator from a modular space X ρs(ϕ) to the generalized Orlicz sequence space lϕ.
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Book review: L Block. (2011). From Politics to Policing: The Rationality Gap in EU Council Policy-Making The Hague: Eleven International Publishing. ISBN: 978-94-9094-737-8, 361 pages.
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We report that the internal quantum efficiency for hydrogen generation in spherical, Pt-decorated CdS nanocrystals can be tuned by quantum confinement, resulting in higher efficiencies for smaller than for larger nanocrystals (17.3% for 2.8 nm and 11.4% for 4.6 nm diameter nanocrystals). We attribute this to a larger driving force for electron and hole transfer in the smaller nanocrystals. The larger internal quantum efficiency in smaller nanocrystals enables a novel colloidal dual-band gap cell utilising differently sized nanocrystals and showing larger external quantum efficiencies than cells with only one size of nanocrystals (9.4% for 2.8 nm particles only and 14.7% for 2.8 nm and 4.6 nm nanocrystals). This represents a proof-of-principle for future colloidal tandem cell.
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In the proof of Lemma 3.1 in [1] we need to show that we may take the two points p and q with p ≠ q such that p+q+(b-2)g21(C′)∼2(q1+… +qb-1) where q1,…,qb-1 are points of C′, but in the paper [1] we did not show that p ≠ q. Moreover, we hadn't been able to prove this using the method of our paper [1]. So we must add some more assumption to Lemma 3.1 and rewrite the statements of our paper after Lemma 3.1. The following is the correct version of Lemma 3.1 in [1] with its proof.
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The MODE-GAP project was established to identify the optimum fiber type for use beyond the capacity crunch. This paper will review some of the key drivers behind the project and analyze the key limits and potential improvements © 2013 IEEE.
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2000 Mathematics Subject Classification: Primary 14H55; Secondary 14H30, 14J26.
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Based upon unique survey data collected using respondent driven sampling methods, we investigate whether there is a gender pay gap among social entrepreneurs in the UK. We find that women as social entrepreneurs earn 29% less than their male colleagues, above the average UK gender pay gap of 19%. We estimate the adjusted pay gap to be about 23% after controlling for a range of demographic, human capital and job characteristics, as well as personal preferences and values. These differences are hard to explain by discrimination since these CEOs set their own pay. Income may not be the only aim in an entrepreneurial career, so we also look at job satisfaction to proxy for non-monetary returns. We find female social entrepreneurs to be more satisfied with their job as a CEO of a social enterprise than their male counterparts. This result holds even when we control for the salary generated through the social enterprise. Our results extend research in labour economics on the gender pay gap as well as entrepreneurship research on women’s entrepreneurship to the novel context of social enterprise. It provides the first evidence for a “contented female social entrepreneur” paradox.
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This study explores differences between men and women entrepreneurs and social entrepreneurs. It explores the barriers and discriminatory effects that hinder women’s entrepreneurship, including access to finance in the European Union. The study includes four case studies covering the situation in the Czech Republic, Italy, Sweden, and the United Kingdom.
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Preceding research has made hardly any attempt to measure the ecological impacts of pro-environmental behaviour in an objective way. Those impacts were rather supposed or calculated. The research described herein scrutinized the ecological impact reductions achieved through pro-environmental behaviour and raised the question how much of a reduction in carbon footprint can be achieved through voluntary action without actually affecting the socio-economic determinants of life. A survey was carried out in order to measure the difference between the ecological footprint of “green” and “brown” consumers. No significant difference was found between the ecological footprints of the two groups—suggesting that individual pro-environmental attitudes and behaviour do not always reduce the environmental impacts of consumption. This finding resulted in the formulation of a new proposition called the BIG (behaviour–impact gap) problem, which is an interesting addition to research in the field of environmental awareness gaps.
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A szerző arra a kérdésre keresi a választ, hogyan alakulhat ki látványos szakadék az egyéni cselekvések iránya és azok együttes hatása között. A szándékok és tettek hatását felülírhatja a társadalmi gazdasági tényezőkből adódó tehetetlenség: a kritikus tömeg hiánya, szervezeti-infrastrukturális tényezők, kompenzációs hatások, egymás hatását kioltó cselekvések. A szerző a környezettudatosság és az ökológiai lábnyom példáján - ezerfős reprezentatív felmérésre alapozva - mutatja be, hogy az önkéntességre alapozó megközelítés sokszor túlbecsüli a fogyasztó - társadalmi-gazdasági tényezők által korlátozott - lehetőségeit és szuverenitását. _____ Behaviour impact gaps are demonstrably present in everyday life. It is increasingly found that environmental awareness in individuals fails to lead to reductions in the ecological footprint. Intensive agricultural practice reduces biodiversity in the EU even in areas where massive agri-environmental grant schemes are available and applied. Labour market training programmes do not necessarily facilitate job-finding for underprivileged segments of the society. So individual efforts may not add up or induce the expected effect. This outcome appears even for programmes that are successful in attaining the required behavioural change in a target group. The impact of attitudes and individual acts may be wiped out by structural and economic lock-ins such as trade-offs made for the gains, lack of a critical mass of actions, infrastructural deficiencies, or interfering acts of economic actors. The discrepancy between environmental awareness and ecological footprint is used to point out how awareness-raising programmes may miss their targets by overestimating the sovereignty and capabilities of consumers. Consumers are unwillingly locked into unsustainable practices and cannot be moved from that position unless economic and structural premises are also changed.