1,721,028 research outputs found
Hybrid systems for distributed power generation based on pressurisation and heat recovering of an existing 100 kW molten carbonate fuel cell
No full text
Computerized image analysis applied to inspection of vetch seeds for varietal identification
No full textVicia sativa L. is an annual cleaning crop mainly used in rotation with durum wheat, both for seed production and for forage, either as a pure crop or as an undercrop, and is well adapted to the hot-dry climate and poor soils of Southern of Italy. Generally, cultivar identification is done on the basis of distinctive traits, such as shape, size, colour of the testa and ornamentations, identified during the variety registration, following official protocols. For some vetch varieties seed identification by specialized technicians is possible without difficulty, while for other varieties it is very difficult and sometimes impossible to achieve undoubted identification. Therefore, it is important, from both technical and economical points of view, to have a quick, reliable, repeatable, and non destructive method to be able to identify and classify seeds objectively. In order to promote computerised image analysis as a tool to aid visual inspection and replace human judgement in the discrimination of different seeds, this technique was applied to analyse and identify seeds of common vetch varieties. Seed size, shape and colour of nine Italian cultivars of common vetch (Vicia sativa L.) and one of hairy vetch (Vicia villosa Roth.) were measured using digital images acquired by a flatbed scanner and, on the basis of a Linear Discriminant Analysis algorithm, a statistical classifier able to identify the ten cultivars was implemented
Morpho-colorimetric analysis and seed germination of Brassica insularis Moris (Brassicaceae) populations
No full textBrassica insularis is a perennial plant growing on both coastal and inland cliffs. Three seed lots from Sardinia were analysed using an image analysis system to detect differences in seed morphology, both within and among populations. Germination requirements at constant (5-25 °C) and alternating temperatures (25/10 °C), both in light and in darkness, were evaluated for all populations. In addition, the effect of a dry after-ripening period (90 days at 25 °C) was also investigated. Morpho-colorimetric analysis clearly identified seeds from different populations and discriminated three chromatic categories for seeds belonging to the Isola dei Cavoli coastal population, but not for the inland Masùa and the coastal Planu Sartu. Inter-population variability was also observed in germination behaviour. B. insularis seeds germinated, with percentages up to 60%, in a wide range of temperatures (5-25 °C), and neither light nor dry after-ripening affected final germination percentages. Moisture content measurements were made for seeds of each colour, but there were no particular differences among colours. Inter-populational variability in germination behaviour may be a survival strategy for species growing under unpredictable environmental conditions, such as under Mediterranean climate, while heteromorphy may be due to independent evolutionary divergence processes of the Isola dei Cavoli population
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
Seed morpho-colorimetric analysis by computer vision: a helpful tool to identify grapevine (Vitis vinifera L.) cultivars
No full textBackground and Aims: The Sardinian wine heritage consists of 151 cultivars; however, because of the different dialects within the same region, many of these cultivars can be considered as false attributions (synonyms/homonyms). The aim of this study was to use seed morpho-colorimetric features to discriminate among the grapevine cultivars and identify synonymy groups. Methods and Results: Over two seasons, 230 grapevine accessions belonging to 115 Sardinian native cultivars (54 black berries and 61 white berries) were collected. Seed images were acquired and analysed. Thirty-three morpho-colorimetric attributes and 80 elliptic Fourier descriptors were assessed. The data were analysed by applying linear discriminant analysis to implement statistical classifiers able to identify the landraces. Fourteen black berry synonymy groups and eight independent cultivars, and 15 white berry synonymy groups and nine independent cultivars, were identified. Conclusions: These results confirmed the synonymy groups previously proposed and improved some of them with other local cultivars. Significance of the Study: Despite different historical and cultural consumption purposes, some cultivars belong to the same synonymy groups, causing apparent incongruence. Nevertheless, the results are consistent with the geographical distribution of the cultivars and with the historical and cultural knowledge in Sardinia
Germplasm image analysis of Astragalus maritimus and A. verrucosus of Sardinia (subgen. Trimeniaeus, Fabaceae)
No full textThe relationships between A. verrucosus Moris and A. maritimus
Moris, exclusively endemics of Sardinia, are studied with a
germplasm image analysis system. Morphometric and colorimetric
features of the seeds and fruits of the two taxa have been
studied and statistically elaborated to verify and confirm the validity
of these species and to improve the performance of the
correct classification of the image analysis system, previously
elaborated to be a tool for taxonomic studies
Influence of storage time and conditions on durum wheat semolina breadmaking performances
No full textDurum wheat semolina is mostly used for the preparation of pasta and couscous and, in the Mediterranean area, it is also used to make bread. Several studies have assessed the ability of image analysis techniques to study bread quality. This is affected by several factors, such as the flour nature, the milling techniques and bread-making process, yeast type, water content of dough and the use of enzymes and other additives. However, the physico-chemical changes occurring during storage of flour and semolina might affect their technological properties; in particular, it is established that starch damage (or depolymerization) at a certain extent has a negative effect on bread structure.
Many studies have addressed the shelf life of bread as a function of the bread-making process, raw materials and additives, however no study has investigated the role of semolina ageing on the bread-making performances. The aim of the present research was to assess the influence of durum wheat semolina ageing on the physical characteristics of bread by image analysis. Bread loaves were produced from semolina samples stored in 4 different packaging materials up to 150 days. Sampling and bread-making trials were performed every 15 days. Results show that ageing does affects durum wheat semolina bread-making performances, highlighting that storage time, rather than the type of packaging material, is the main factor determining quality changes in the final bread samples. In particular, a reduction of the bread slice area and height was observed with increasing semolina storage time, while a slight increase of crust and pore % areas was observed
Identification of Italian landraces of bean (Phaseolus vulgaris L.) using an image analysis system
No full text- …
