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Transversal strength of a composite lamina with long unidirectional fibers randomly distributed
No full textThermodynamic performance evaluation of an innovative steam compressor using zeolite-water adsorption reactor
No full textThe industrial sector is a large energy consumer producing huge amounts of low enthalpy waste steam which can be compressed to increase its condensation pressure for its subsequent effective use. In this paper, adsorption technology was used to increase the waste steam enthalpy since this process requires small amounts of electrical energy. An innovative configuration of the adsorption compressors is presented involving direct contact between an adsorbent bed and the waste steam. The direct-contact design avoids the use of a heat exchanger between the steam and the zeolite adsorbent material, thus reducing the geometry complexity and the overall cost. The direct -contact technology is new and generally studied for heat pump purposes. This paper numerically investigates the physical feasibility of the process highlighting its main advantages and limitations. The results show a promising thermodynamic behaviour suggesting the possibility of using this adsorption compressor for several industrial processes involving higher than 7 bar steam pressure and pressure ratios up to 1.26. The steam consumption was lower than one order of magnitude of the usable compressed steam
Energy performance assessment of a novel zeolite-water direct contact adsorptive heat pump for waste heat recovery
No full textThe adsorption heat pumps are a promising technology suitable for the industrial waste heat recovery. In particular, the direct contact configuration can be used to generate high pressure steam for industrial applications limiting the design complexities. In this paper, a numerical simulation of the adsorption phase of an original configuration of a direct contact water/zeolite heat pump is presented and discussed. Two different models have been developed and compared using experimental data. Different sensitivity analyses were carried out with the aim of understanding the process of steam generation. The mass flow inlet results to be one of the most relevant parameters of the process and, consequently, an innovative process configuration is proposed. A descendent inlet water flow is implemented and compared with the classical ascendent process. The simulations on this configuration demonstrated that it is possible to obtain higher steam production and better process performances doubling the generated steam mass flow
Collaborative maintenance of housing quality for social, cultural and economic innovation in marginalised areas
No full textLevelized Cost of Heat for Linear Fresnel Concentrated Solar Systems
Full text linkIn this paper, a deep investigation upon levelized cost of heat (LCOH) produced by small-scale solar linear concentrating Fresnel collectors (CSLFC) is proposed. Solar industrial process heat applications have temperature requirements from about 60 °C to 260 °C. CSLFCs can effectively integrate conventional fossil fuel thermal systems. The study is addressed to assess technology cost projection needed to achieve competitive LCOH. So, on the basis of a framework specifically developed for these economic assessments, the best investment scenarios, in terms of industrial application, geographical location and technical design solutions, where to effectively apply the technology of CSLFC, are highlighted.
The analysis has been focused on specific cost of several existing CSLFCs associated with declared performances at different operating temperatures. Two main classes of CSLFC with different total efficiency (optical and thermal) corresponding to various design solutions and specific cost were selected. The expected performances in the whole application temperature range have been evaluated through Glayx Tech proprietary simulation code, including optical and thermal unsteady analysis.
A huge database coming from full CSLFC simulation varying latitude, yearly DNI, operating fluid, outlet temperature, thermal storage options, has been collected. CLSFC design and performance requirements are the key-choice to achieve competitive LCOH: the use of high efficiency – high cost components is not always rewarding in terms of final LCOH and must be attentively decided basing on site, irradiation, heat quality and LCOH target. In this perspective, CLSFCs are the most promising for industrial small scale heat applications since they show the greatest potential to reduce manufacturing costs
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
Stability of a thermophilic TIM-barrel enzyme: indolglycerol-phosphate synthase from the thermophilic archaeon Sulfolobus solfataricus.
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