369 research outputs found

    Aerodynamic design optimization of wind turbine airfoils under aleatory and epistemic uncertainty

    Get PDF
    This paper presents different approaches to optimize wind turbine airfoils in an uncertain scenario. The approaches are specifically applied to the aerodynamic design optimization of a wind turbine airfoil accounting for the uncertainty in setting up the XFOIL's NCRIT constant: a parameter that is considered affected by a chain of aleatory and epistemic uncertainty. Subject to a set of aerodynamic and structural constraints, the uncertain response of the airfoil is optimized by means of both probability- and imprecise probability-based approaches. These solutions are compared with a reference airfoil optimized with a conventional design approach, in which the treatment of uncertainty is carried out in a simplistic fashion. Once evaluated in the probabilistic scenario, the airfoil designed with the conventional approach still achieves the largest aerodynamic efficiency mean. This airfoil is however affected by the largest performance sensitivity to NCRIT variations. The airfoils optimized by means of uncertainty-based approaches instead achieve larger performance robustness and reliability than the airfoil optimized with the conventional approach

    Education and Sustainability: The Case of Emotions Park

    Get PDF
    Firms working in the third millennium have to face the challenge of being more sustainable. The complexity and the multidisciplinary nature of sustainability also requires new and specific knowledge. This means the necessity of a critical rethinking of the education system in the way to provide the cognitive tools and applications needed for new generations to address environmental, economic, and social challenges. In this perspective, the role of the school it is crucial, above all, to encourage attention to include sustainability as a theme on educational programs, focusing on the promotion of its multiple dimensions. Interdisciplinary sustainability programs are emerging globally, but little is known about the learning in these educational contexts. Therefore, the current research explores training modules used in the activities of a park to verify how students can receive a sustainable education from primary school; whether and in which way education can be a driver for the promotion of sustainable development; and whether it is effective to insert eco-activities such as eco-games, eco-campus, and eco-sports in the training modules from primary school onwards. For this purpose, the paper employed a single case study approach using the Emotions Park as a teaching plan. In particular, game and sports constantly accompany the training process by creating interdisciplinary links with different study subjects (e.g., civic education, environmental education, communication). Through the eco-activities, an innovative way to promote environmental and sustainability education was explored as a training model. Outdoor play, observation, and stimulation of the senses have proved powerful learning tools, and key to the acquisition of skills. Research data were collected observing the behavior of a sample of 22 participants and through face-to-face semi-structured interviews with educators, employee and students. The empirical observation suggests that inserting the sustainability principles as a topic in didactic programs provides the cognitive tools and applications needed for the new generations to address environmental, economic, and social challenges

    Growth of monolayer graphene on 8deg off-axis 4H-SiC (000-1) substrates with application to quantum transport devices

    Full text link
    Using high temperature annealing conditions with a graphite cap covering the C-face of an 8deg off-axis 4H-SiC sample, large and homogeneous single epitaxial graphene layers have been grown. Raman spectroscopy shows evidence of the almost free-standing character of these monolayer graphene sheets, which was confirmed by magneto-transport measurements. We find a moderate p-type doping, high carrier mobility and half integer Quantum Hall effect typical of high quality graphene samples. This opens the way to a fully compatible integration of graphene with SiC devices on the wafers that constitute the standard in today's SiC industry.Comment: 11 pages, 4 figures , Submitted in AP

    Lipid Process Markers of Durum Wheat Debranning Fractions

    Get PDF
    At present, whole grains are usually obtained by adding bran and middlings to refined flours, and this recombination leads to certain variations in the ratio of endosperm, bran and germ, resulting in flours with very different compositional characteristics and rheological properties. Therefore, this study focuses on the identification of specific lipid markers in different debranning fractions of Italian and Canadian durum wheat blends. The by-products obtained from five different debranning levels (3, 6, 9, 12 and 15%) had a high content of monounsaturated fatty acids and a higher concentration of tocopherols and sterols than the corresponding debranned grains. The Italian and Canadian durum wheat samples did not show significant differences in the content of these bioactive lipid compounds. In particular, palmitic acid, oleic acid, tocopherol isomers and total sterols could be useful biomarkers for evaluating the grain-to-tissue ratio in recombined flours

    Cryopreservation of hazelnut (Corylus avellana l.) axillary buds from in vitro shoots using the droplet vitrification method

    Get PDF
    Cryopreservation by droplet vitrification was applied to hazelnut (Corylus avellana L.). axillary buds of the Italian cultivated variety Tonda Gentile Romana, which were collected from in vitro growing shoots, immersed in ice cooled PVS2 or PVS3 for 60 or 90 min, then transferred to a droplet of vitrification solution, placed on a strip of aluminium foil, and plunged into liquid nitrogen (LN). Additionally, the effect on the recovery of the mother plant after cryopreservation was evaluated, following a cold pre-treatment at 4â—¦C for 3 months. The highest regrowth percentage (56.7%) was obtained after applying PVS3 for 60 min, while the application of PVS2 for the same amount of time reduced regrowth to 41.5%. Increasing the exposure to vitrification solutions to 90 min reduced regrowth to 43.3% when PVS3 was applied, and 35.6% if PVS2 was used. The cold pre-treatment on the mother plant did not significantly improve overall regrowth. The cryopreservation process did not decline the rooting ability of the recovered shoot

    Presence and distribution of the brown bear (Ursus arctos) in Friuli Venezia Giulia, from 2004 to 2011, through the non-invasive genetic monitoring ad conservation implications

    Get PDF
    After having disappeared at the beginning of 1900, the brown bear has started in a late 1960s a slow process of recolonization of the north-eastern Alps, through an expansion of Dinaric population. At the end of the 1990s the University of Udine began the occasional monitoring of the species and from 2004 non-invasive genetic monitoring became systematic. In the last 8 years 217 hair traps have been activated in the region to monitore: Natisone Valleys, the Julian and Carnic Alps and Prealps. Twenty-six hair traps were monitored in all years, whereas 40 were observed only in 2004, 2007 and 2011. The 26 hair traps constantly monitored from 2004 to 2011 showed 17% of average success of hair’s collecting (brown bear samples collected/day control: BBSD). The 40 hair traps, monitored in the window period, showed 12% of BBSD. The BBSD value varied in relation to both season (highest in spring) and year, with a dramatic decline from 2008, and interaction between year and area. From 2004, 13 genotypes, through systematic hair traps monitoring, were identified, while only 2 genotypes were sampled opportunistically. It was observed a high turnover of the genotypes: only 7 genotypes were sampled for more than 2 years (47% of total), 4 genotypes (27% of the total) were sampled for 3 years or more. The annual attendance of bear have been constant from 2004 to 2007, with 5-6 genotypes present every year. In the period between 2008 and 2010 there was a drastic decrease in the successful collection at the hair traps, with and average of 1-2 animals genotyped per year. However, opportunistic samples have increased in the recent times, probably due to the arrivals of 3 genotypes from Trentino (KJ2G2 in 2009 and DG2 and MJ4 in 2011). The year 2011 showed a further increase in the presence of bears with 5 animals genotyped in Friuli Venezia Giulia. Three of these animals belonged to the Slovenian population, while the other 2 genotypes were from the Trentino population. The results seem to confirm the exchange of some individuals between the Dinaric and central alpine population. As an example, the dinaric bear M5 was genotyped in Friuli Venezia Giulia in 2008 and then sampled in 2009 and captured in 2010 in Trentino and finally slot in Slovenia in 2011. The distribution in the alpine and prealpine areas has changed year by year: from the 2004 to 2007 the Natisone Valley and the Julian prealpine areas along the border with Slovenia were the areas more used, whilst from 2009 there was an apparent higher presence of bears in the Carnian Prealps and Alps, and in the Julian Alps. This shift could be due to human disturbance (i.e hunting management), control of the species carried out in neighbouring Slovenia, with a decreasing of immigrant from dinaric populations, and new immigration of bears from the central Alps. The present work has highlighted the necessity for a trans-regional and cross-border management of the species, especially in consideration to the population control applied in Slovenia, which seem to limit the Dinaric population expansion in the Alps, and furthermore the philopatry behaviour of bear females, which implies the absence of females in Friuli Venezia Giulia and induces a movement bach to Slovenia (at least 3 bears genotyped in Italy were shot in Slovenia). All these elements seem to exert important limitations to the consolidation and stabilization of the population of brown bears in north-eastern Alps. From the methodological point of view the protocol of systematic non-invasive genetic monitoring, shared at the trans-regional and trans-boundary level, is fundamental to monitore the dynamics and distribution of bear; the protocol should follow a systematic experimental design and should be integrated with a efficient opportunistic data collection

    Use of sieving as a valuable technology to produce enriched buckwheat flours: A preliminary study

    Get PDF
    Fractionation processes based on physical separation are a good strategy to produce enriched cereal flours. Therefore, the aim of this work is to evaluate the suitability of sieving of buckwheat flours to produce protein and phenolic (especially rutin) enriched fractions. Because of that, dehulled whole buckwheat flour (GSTQ) was sieved obtaining fractions with a particle size of 215 \uf06dm, 160 \uf06dm, 85 \uf06dm, and 45 \uf06dm (GS215, GS160, GS85, and GS45). For that purpose, the determination of protein, ash, and total starch content and free and bound phenolic compounds was carried out. The highest content of total phenolic compounds was obtained in GS215 (3118.84 mg kg-1 d.w.), followed by GS160 (2499.11 mg kg-1 d.w.), GS85 (989.46 mg kg-1 d.w.), GSTQ (983.15 mg kg-1 d.w.), and GS45 (481.31 mg kg-1 d.w.). Therefore, the phenolic content decreased with the particle size decrease from 215 \uf06dm to 45 \uf06dm. Besides, there were no significant differences between the total phenolic content in GS85 and GSTQ. The fraction with 215 \uf06dm reported the highest protein and mineral salt content and presented rutin amounts four times higher than GSTQ

    EpiHRMAssay, in tube and in silico combined approach for the scanning and epityping of heterogeneous DNA methylation

    Get PDF
    Reliable and cost-effective assays with adequate sensitivity are required to detect the DNA methylation profile in plants for scientific and industrial purposes. The proposed novel assay, named EpiHRMAssay, allows to quantify the overall methylation status at target loci and to enable high-throughput analyses. It combines in tube High Resolution Melting Analysis on bisulphite-treated templates with the in silico prediction of the melting profile of virtual epialleles using uMELTSM software. The predicted melting temperatures (Tm-s) of a set of epialleles characterized by different numbers of methylated cytosines (#mC) or different mC configurations were obtained and used to build calibration models, enabling the quantification of methylation in unknown samples using only the in tube observed melting temperature (Tm-o). EpiHRMAssay was validated by analysing the promoter region of CMT3, DDM1, and ROS1 genes involved in the regulation of methylation/demethylation processes and chromatin remodelling within a population of peach plants. Results demonstrate that EpiHRMAssay is a sensitive and reliable tool for locus-specific large-scale research and diagnostic contexts of the regulative regions of genes, in a broad range of organisms, including mammals. EpiHRMAssay also provides complementary information for the assessment of heterogeneous methylation and can address an array of biological questions on epigenetic regulation for diversity studies and for large-scale functional genomics
    • …
    corecore