1,720,960 research outputs found
Efficienza energetica e fonti rinnovabili per l’agricoltura protetta
No full textIntroduzione
Il comparto dell’agricoltura protetta (serre in vetro, serre in plastica, tunnel e tunnellini) si
trova oggi a operare in un un mercato internazionale caratterizzato da una costante evoluzione
rispetto sia alla richiesta dei consumatori per le garanzie di “food safety” e sia alla necessità
di ridurre i costi energetici per la climatizzazione delle serre. Pertanto, l’impiego da parte
delle aziende agricole di modelli produttivi caratterizzati da un lato dalla più ampia diversificazione di prodotti vegetali e dall’altro lato da una maggiore efficienza energetica insieme all’applicazione
di tecnologie di climatizzazione che utilizzano energie rinnovabili risultano
ormai fondamentali per rispondere efficacemente alla competizione globale. Le conseguenze di questa situazione si manifestano a diversi livelli della filiera agro-alimentare con prospettive e obiettivi molteplici, tra i quali i principali sono: la valorizzazione di processi produttivi
eco-compatibili, la scelta della sostenibilità energetica ed ambientale come elemento chiave di
competitività, la coerenza con le policy Europee inerenti l’energia, l’efficienza energetica, l’ambiente e lo sviluppo economico sostenibile
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
Photovoltaic as sustainable energy for greenhouse and closed plant production system
No full textIn this paper, a description is given about a project concerning the development of a prototype of a closed greenhouse module, designed as a container unit with dimensions of 6055 (l)*2435(w)*2585(h) mm, and equipped with a stand-alone PV system. The project represents the follow up of an on going cooperation research project startef on 1997 by the ENEA institute in Antarctica, and addressed to realise a closed hydroponic module for supplying of plant fresh food to personnel of the Italian base “Mario Zucchelli”. The prototype has been installed in the Iblean territory of the Sicilian region in South Italy, (37° of latitude, and an average yearly value of incoming solar radiation ranging from 1750 to 2180 kWh/m2). The main objective is to test the real capacity of the photovoltaic technology to produce electricity for closed greenhouses. The prototype under investigation is powered by a photovoltaic system made of 6 PV modules able of delivering 1.1 kW of instant DC power, and mounted on the roof of the prototype. The DC power can be converted into AC power via a DC/AC inverter or stored in a battery bank, 24V and 900 Ah. Experiments are in progress to evaluate the PV electricity generation and its efficiency, the PV equipment, the plant crop performance and the economic aspects
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
The PULSA (Plant-based Unit for Life Support in Antarctica): a sustainable plant food technology for remotes and isolated environments
No full textIn the last decade ENEA (Italian National Agency for New Technology, Energy and the Environment) has promoted some research projects with the aim to develop a system and a protocol for producing fresh vegetable food in the Italian bases of TNB (Terra Nova Bay) and Dome C (Concordia base) situated in Antarctica, with the main result of the construction of the Plant-based Unit for Life Support in Antarctica (PULSA). The paper reports a brief overview of the main prototypes and software developed with the cooperation of the Universities of Pisa and Palermo. This cooperation had produced the main following products: 1) a complete automatic hydroponic system for plant cultivation in artificial environment (C.H.G.S., Closed Hydroponic Greenhouse System); 2) a recycling wastes unit for the purification of water and the recycling of the residual biomasses produced by hydroponic growing cycles; 3) a complete automated and remote-controlling system for the germination and the production of the plantlets (Box-Nursery); 4) a lettuce growth and yield simulator (SLS). In addition, the paper describes also the last prototypes under development, such as a multilevel hydroponic growing unit and a solar photovoltaic system, developed with the aim to maximize the yield, using also the Light Emitting Diodes (LEDs) as light source for plant crop growth. Considerations and comments on the possibility to use PULSA as scientific platform for research and demonstration activities on plant growth technologies useful for the Space are also reported. All the researches herein presented were financed by the PNRA (Italian National Plan for Antarctic Research)
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