1,720,966 research outputs found
Harvesting techniques for Sorghum bicolor in northern Italy
No full textOver the last years several field trials have been carried out in Italy in order to find suitable energy crop species and select specific varieties for large scale biomass production. Currently, Sorghum bicolor is considered to be an interesting and promising biomass crop for Northern Italy due to its abundant biomass production as well as its yearly vegetation cycle, which is easier to approach by most of the farmers compared to the perennial crops, allowing more flexibility in farm management.
A 20 hectares field trial was cultivated with Sorghum bicolor during the summer 2007 in the framework of a project founded by the Emilia-Romagna Region. The aim of the trials was to assess and compare two harvesting chains, one related to biogas production and the other one addressed toward obtaining dried and bailed biomass for a combustion plant. The results demonstrated that the first harvesting method (chopping and loading on dumper) is suitable for collecting wet biomass as biogas production feedstock and it does not display any particular problems even when high efficient harvesting machineries available on the market are used.
The second harvesting method (mowing-conditioning-drying-baling) showed some problems related to the short period of time available for the crop in order to achieve the right moisture. It also brought to excessive biomass losses
Transnational Biodiesel Chains Approach: Feasibility Issues in the Italian Perspective
No full textIn March 2007, the European Council agreed on a 10 % binding minimum target to be achieved by all Member States for the share of biofuels in overall EU transport petrol and diesel consumption by 2020. This target complements the overall goal of the 2003/30/EC Directive to achieve a 5.75% biofuels share by 2010.
Considering the specific case regarding biodiesel, this paper aims to verify if the EU recommendations represent an achievable target and if conditions exist for developing transnational biodiesel production chains in Europe. This work summarize part of the activities of the BETTER project “Biofuels chain Enhancement for Territorial developmenT of European Regions” within the framework of the INTERREG IIIB CADSES Neighborhood
DEVELOPMENT OF A PROTOTYPE IMPLEMENT FOR ARUNDO DONAX HARVESTING FOR COMBUSTION PURPOSE
No full textIn the last years a particular interest has been addressed to perennial herbaceous crops as energy feedstock, in particular, Arundo donax.
The aim of research was to set up appropriate winter harvesting chains in order to obtain bales suitable for medium/long term storing. A stem-shredder prototype was developed. The tool is set in front of a tractor in order to cut the stems before the tractor passage and allowing to discharge the shredded product in row. Tests on Arundo donax were carried out in the Po Valley, the crop was harvested in winter 2006, 2007 and 2008, in its second, third and fourth life cycle year. The biomass in row was baled with two different round baler system: a fix chamber and a variable chamber. Field efficiency (ha/h), moisture of the harvested biomass and energy balance were assessed. The machineries equipment developed has shown positive working performances, although it appears necessary to increase the cutting width of the prototype, in order to improve its field efficiency, and to optimize its features in order to gain a more uniform chopping and therefore lower field loss.
The positive energy balances, confirm Arundo donax as one of the most promising crop for obtaining high yields biomass production
The use of an electronic beet to evaluate sugar beet damage at various forward speeds of a mechanical harvester
No full textMechanical harvesting strongly affects the quality of sugar beets, mainly in terms of root injuries, tare, and extracted sugar. In Mediterranean countries, the effects of sugar beet damage are more critical because of the warm and humid climate at harvesting time. In order to investigate the dynamic interaction between mechanical tools and roots, electronic devices have been developed in some European countries for measuring impacts experienced by roots when passing through the harvesters. At the University of Bologna, an electronic beet with a 4905 m/s2 tri-axial accelerometer was developed in 1998. This device was used in a field trial for measuring and recording impacts in terms of peak acceleration, duration, and velocity change during impact. The device was placed into the soil in place of a real beet and then harvested by a six-row self-propelled harvester, which was tested at four different forward speeds. Assessments of the level of damage on the harvested sugar beets were also carried out according to the IIRB international method. The aim of the study was to evaluate how different forward speeds tested on a single harvester can affect damage to the roots, to assess the damage caused at each step of the harvesting process, and to find a correlation between damage and impacts. Mechanical parameters recorded by the electronic beet were referenced to three specific positions, defined as A, B, and C zones, within the harvester. The ANOVA results in A zone, composed of lifting shares and roller bed, and in B zone, composed of transfer web and turbines, showed a statistical significance. In C zone, composed of tank elevator and tank, the variables had no statistical significance. The results of the trial showed that A zone had the highest values of the variables. A harvester forward speed of 6 km/h caused the fewest taproot breaks and bruises. A linear model describing the relationship between taproot breaks and impact velocity change showed a statistical significance for A zone, while no significance was determined for B zone
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
Organic micropollutants (PAHs, PCBs, Pesticides) in seaweeds of the lagoon of Venice
No full textSamples of seven genera of seaweeds (Ulva, Gracilaria, Porphyra, Grateloupia, Undaria, Fucus and Cystoseira), which can be used as environmental biomonitors and in several applications like human alimentation, animal feeding and cosmetics, were collected in four sampling sites in the Lagoon of Venice in spring and autumn 1999 with the aim of determining the contamination due to organic micropollutants (polychlorinated biphenyls. PCBs; chlorinated pesticides; polycyclic aromatic hydrocarbons, PAHs). On an average, most of the considered species were contaminated especially by PAHs (up to 56 ng g(-1) dry wt. (dw)) whereas concentrations of PCBs and pesticides in macroalgal tissues were significantly correlated and did not exceed 5 ng g-1 dw. Among the studied genera the most contaminated by PAHs were Ulva, Undaria and Cystoseira. The highest concentrations of PCBs and pesticides were found in Cystoseira, Fucus and Gracilaria. The least contaminated genus was Porphyra. Although macroalgal specimens were sampled in differently contaminated areas placed from the mainland to the Lido Lagoon mouth, no quantitatively meaningful differences of concentrations were found among the sampling stations. (C) 2003 Editions scientifiques et medicales Elsevier SAS and Ifremer/CNRS/IRD. All rights reserved
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
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