1,721,008 research outputs found
Hybrid energy network management: Simulation and optimisation of large scale PV coupled with hydrogen generation
Full text linkThe power production of electrical Renewable Energy Sources (RES), mainly PV and wind energy, is affected by their primary source of energy: solar radiation value or wind strength. Electrical networks with a large share of these sources must manage temporal imbalances of supply and demand. Hybrid Energy Networks (HEN) can mitigate the effects of this unbalancing by providing a connection between the electricity grid and and other energy vectors such as heat, gas or hydrogen. These couplings can activate synergies among networks that, all together, increase the share of renewable sources helping a decarbonisation of the energy sector. As the energy system becomes more and more complex, the need for simulation and optimisation tools increases. Mathematical optimisation can be used to look for a management strategy maximising a specific target, for instance economical, i.e. the minimum management cost, or environmental as the best exploitation or RES. The present work presents a Mixed Integer Linear Programming (MILP) optimisation procedure that looks for the minimum running cost of a system made up by a large-scale PV plant where hydrogen production, storage and conversion to electricity is present. In addition, a connection to a natural gas grid where hydrogen can be sold is considered. Different running strategies are studied and analysed as functions of electricity prices and other forms of electrical energy exploitation
ASSOCIATION BETWEEN THE POLYMORPHISM AT CASEIN LOCI AND MILK FATTY ACID COMPOSITION IN GIRGENTANA GOATS
No full textcomposition is an important trait for the goat dairy industry because of its influence on cheese yield and
the organoleptic properties of dairy products (Chilliard et al., 2003). Goat milk is particularly rich in
saturated fatty acids (SFA) whereas monounsaturated (MUFA) and polyunsaturated (PUFA) FA are less
abundant (Fontecha et al., 2000).The aim of this work was to provide new data to better understand the
influence of polymorphism at casein loci on fatty acid profile in Girgentana goat milk.
One hundred lactating Girgentana goats, homogeneous for milk production, days of lactation, body weight
and diet were used. The procedure was developed using individual raw milk samples, collected in three
different stages of lactation: (October, February and June) from individuals with known genotypes at casein
loci. Were analyzed animals with A*A*, B*B*, A*B*, FF, A*F, B*F, A*E, EF, FN, NN and A*N genotypes
(where A* indicates A, G, I, and H alleles while B* indicates B1, B2, B3, B4 and C alleles) at αs1‐casein; CC,
AC, A0', AC', C0', CC', and C'C' genotypes at β‐casein; AA, AC, AF, CF, EF and FF genotypes at αs2‐casein; and
AA, AB, AD, AN, BB, BD, BN, DD and D'G genotypes at κ‐casein. Milk samples were prepared following the
Rose‐Gottlieb’s method (1996) for FA extraction. For transesterification of the lipids KOH in methanol 2 N
was used and thereafter the fatty acid methyl esters (FAMEs) were analyzed with a chromatographic
method (Sağdiç et al., 2003).The determination of the fatty acid profile was performed by gas
chromatography SHIMADZU GC‐2010 with flame ionization detector (GC‐FID). The FAMEs were injected
into a capillary column (Zebron ZB‐WAX Plus 30m x 0:32 mm id, 0.2 mM film), identified according to the
retention times and quantified by calibration curves. The results of fatty acid were expressed as g/100g
total fat.Data set was analyzed using GLM procedures for repeated measure of SAS System v9.2.
For almost all the fatty acid the environmental factors flock and month of sampling showed statistically
significant differences. Among all the fatty acids investigated only two showed statistically significant
differences between genotypes for κ‐casein, in particular C18 (stearic acid) and C18:01 (oleic acid). For αs1‐
, αs2‐ and β‐casein were not found statistically significant differences.
The results showed that genetic polymorphisms at casein genes, in particular at κ‐casein, have important
effects on goat milk fat and FA composition, especially for MUFA and PUFA, which are potentially involved
as positive factors in the health of human consumers
Policies promoting decarbonisation of energy supply under uncertainty: Where, how and when to abate
No full textEnergy supply is responsible of more than 80% of anthropogenic carbon emissions whose rapid accumulation in the atmosphere is in turn responsible of unsustainable global warming (overshoot of 1.5°C) to avoid which carbon neutrality should be achieved in a few decades. "Accelerating" the (supposed) decarbonization of energy supply in sectors different of power generation is commonly considered a necessary step to reach such a goal. Nevertheless, this article points out that (at least in principle) this kind of "acceleration" (e.g. through indiscriminate targets and stringent policy provisions, including over-subsidies for RES producers) might not be desirable. In fact, the allocation of renewables (among different uses, different abatement carriers and over time) is by no means a trivial choice. To explain why, we focus on thermal and transport sectors and analyse the main energy carriers of abatement (electrification, biomethane and hydrogen), looking for intertemporal and interspatial optimization of renewables allocation, by estimating the LSCOA (levelized social cost of abatement), and by accounting for uncertainty about energy prices and renewable costs. The principal conclusion is that, before electricity supply is fully decarbonised, only greenfield biomethane should be allocated to thermal and transport uses, in the meantime "accelerating" the allocation of electric renewables to power generation. Only when this latter is almost completely decarbonised, policies should promote deep green (now really) electrification of thermal (not "hard to abate") and transport (light-duty) uses. Otherwise, the risk is to significantly slow down the entire process of energy supply decarbonization, and even to undermine the achievement of the climate targets. Finally, regarding green hydrogen, it should be allocated to the so-called "hard to abate" uses (including heavy transport) and to improve (as storage option) electric renewable competitiveness
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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