1,721,276 research outputs found
Effect of finite-rate catalysis on wall heat flux prediction in hypersonic flow
No full textThis work deals with the simulation of hypersonic flows past a copper sphere by using a finite-rate catalysis model coupled with either a state-to-state (StS) or a multitemperature thermochemical nonequilibrium approach. Without detailed state-specific data for copper catalytic recombination, molecules formed on the surface are described with three different statistics: one reproducing the incoming distribution, one considering a uniform distribution, and the third populating only the highest vibrational level. Following recent experimental and theoretical results, very high enthalpy and very low pressure conditions have been considered. The finite-rate partial catalysis model provides results that are closer to the experimental ones than those obtained by a fully catalytic approach. The multitemperature model shows better agreement with experiments, whereas among the StS catalytic approaches the outcomes have shown that the surface recombination on only the highest energy level gives more accurate results
Impact of fundamental molecular kinetics on macroscopic properties of high-enthalpy flows: The case of hypersonic atmospheric entry
Full text linkThermochemical nonequilibrium is one of the most challenging issues when dealing with hypersonic flows experienced by objects (space vehicles, meteoroids, space debris) at atmospheric entry. The case of a hypersonic flow past a sphere is considered as a test model for systems in strong chemical and thermal nonequilibrium conditions, mimicking the extreme environment experienced by objects entering a planetary atmosphere. The problem has been studied using the state-to-state approach, calculating directly the distribution of vibrational levels of O2 and N2, together with the flow field, including also viscous effects. Nonequilibrium distributions are observed and the results have been compared with macroscopic experimental data, showing that the state-to-state model is able to provide better capabilities for predicting experimental results than the traditional multitemperature approach. The use of graphics processing units allowed us to obtain these results in a two-dimensional configuration, opening additional perspectives in the investigation of reacting flows
In need of a sustainable and just fashion industry: identifying challenges and opportunities through a systematic literature review in a Global North/Global South perspective
No full textSince the late twentieth century, the global fashion industry has been increasingly embracing the business model known as fast fashion. Characterised by rapid production cycles, fleeting trends, low-cost garments and large-scale production, fast fashion seems to meet consumer demand for affordable and trendy clothing. However, its environmental impact as a major polluter poses significant challenges to sustainability and circularity initiatives. This article presents the results of a systematic literature review, exploring the unsustainable consequences of fast fashion, focusing on both demand and supply side, from a geographical perspective. Using a Global North–Global South framework, it explores differences in socio-economic structures, consumption and production patterns, access to resources and environmental impacts. The analysis suggests that a fair and equitable transition towards a sustainable and circular fashion industry will require the links between business, society and nature to be reconsidered, to avoid perpetuating the inequalities associated with the global linear capitalist economy. The findings highlight the importance of both markets and institutions in sustainable growth. In the Global North, the most frequently discussed topics relate to investment and research and development with respect to new technologies or system innovations often with the support of well-structured political guidance. Conversely, in the Global sustainable initiatives tend to be scattered, country-specific and intricately tied to particular socio-economic and cultural contexts
Il Telecommunications Act statunitense due anni dopo
No full textThe paper analyzes the effects of the 1999 U.S. reform on telecommunications
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
LA PSICHIATRIA DI LIAISON: IL MODELLO DELLA CLINICA PSICHIATRICA DI NOVARA
No full textRELAZIONE PRESENTATA AL SIMPOSIO “I CAMBIAMENTI DELLA CURA IN PSICHIATRIA” XLVIII CONGRESSO DELLA SOCIETA’ ITALIANA DI PSICHIATRIA METAMORFOSI NELLA PSICHIATRIA CONTEMPORANEA:COMPETENZE, ESPERIENZE, TENDENZE. MONTESILVANO, 15 – 20 OTTOBRE 200
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