1,720,962 research outputs found
INTEGRATED THERMAL ENERGY STORAGE SYSTEM - ROLE OF MANAGEMENT STRATEGY IN DESIGN OF A STORAGE TANK
No full textIn recent years, our society has experienced an important energy transition that is becoming a central aspect in geopolitical choices in several countries around the world. However, several issues arise from these scenarios, in which an increasing number of RES power plants are installed and connected to electrical grids. In fact, most renewable sources, such as wind and solar, are characterised by a fluctuating and unpredictable behaviour that causes a decrease in the quality of the energy transmitted through the grid and leads to a more difficult management of the grid itself. To mitigate and reduce these negative aspects, it is important to install devices, such as storage systems, capable of facilitating the correct management of electrical grids, meeting, at the same time, the electrical demand of the users and the energy produced in RES-based power plants. Although several technologies have been proposed over the years, Carnot batteries seem to guarantee adequate performances without stringent geographical constraints and represent a promising solution. Among them, integrated thermal energy storage systems (IT-ESS) can be easily installed and coupled with existing power plants. The central element of such technology is represented by a sensible heat-thermal energy storage device, consisting of a packed bed. The literature is still lacking accurate design methods for the storage tank, and this is the leading aspect that led the authors to develop an innovative procedure to determine the size of the storage device, based on the necessity of producing energy during the night, while the accumulation phase occurs during the day. In this phase, the power of a photovoltaic plant is exploited: the plant is described through curves that reproduce the power generated in a typical day for each month of the year. An algorithm built in the MATLAB environment had been used to determine the volume of the storage device, with the goal of being able to cover the hours in which the PV is not producing energy. The results of the analysis have underlined the need to consider in a proper way both the user needs and the characteristics of the renewable power plants, to correctly evaluate the volume of the storage tank to be installed in the system
Creatine Supplementation to Improve Sarcopenia in Chronic Liver Disease: Facts and Perspectives
Full text linkCreatine supplementation has been one of the most studied and useful ergogenic nutritional support for athletes to improve performance, strength, and muscular mass. Over time creatine has shown beneficial effects in several human disease conditions. This review aims to summarise the current evidence for creatine supplementation in advanced chronic liver disease and its complications, primarily in sarcopenic cirrhotic patients, because this condition is known to be associated with poor prognosis and outcomes. Although creatine supplementation in chronic liver disease seems to be barely investigated and not studied in human patients, its potential efficacy on chronic liver disease is indirectly highlighted in animal models of non-alcoholic fatty liver disease, bringing beneficial effects in the fatty liver. Similarly, encephalopathy and fatigue seem to have beneficial effects. Creatine supplementation has demonstrated effects in sarcopenia in the elderly with and without resistance training suggesting a potential role in improving this condition in patients with advanced chronic liver disease. Creatine supplementation could address several critical points of chronic liver disease and its complications. Further studies are needed to support the clinical burden of this hypothesis
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
Optimization and assessment method to approach industrial site decarbonization: A case study of a light industry
No full textThe industrial sector includes a wide range of industries and processes for which a single approach or universal strategies for decarbonization can hardly be identified. In general, the most efficient way to decarbonize building sites consists of two phases: (i) reduce the energy demand and (ii) replace the fossil-based power generation units with renewable energy sources, possibly working on the management of HVAC systems to reduce the required peak power. Literature provides general rules and schemes, but no specific works on the energy retrofit of industrial buildings have been found in literature so far. The present study investigates an existing industrial district, using dynamic energy models of buildings tuned with the current conditions and compared with seven decarbonization scenarios. A neutral water loop exchanging heat with the ground has been studied, representing a widely replicable solution due to the higher heat exchange efficiency and the modular installation, which can be expanded within the site. The significant energy savings (28%) and CO2 emission reduction (up to 70%) obtained are representative of the potential achievable for many industrial sites in mild European climates, where decarbonization should achieve optimal cost-benefit results while minimizing the impact on the production through modular approaches
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