591 research outputs found

    Numerical Investigation of Installed Jet Noise Sensitivity to Lift and Wing/Engine Positioning

    Get PDF
    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.As the turbofan engines of modern transport aircraft have increasingly larger bypass ratios, by necessity to avoid longer undercarriage, the engine must be installed closer to the wing. This then has the potential of interaction between the jet flow and a deployed flap. This interaction can be an important noise source when the high-lift systems are deployed, as at approach and take-off. Investigating the parameters that have a strong influence on the installation noise penalty can help in identifying noise reduction measures. In this paper Wall-Modelled Large Eddy Simulations (WMLES), combined with the FfowcsWilliams and Hawkings (FW-H) sound extrapolation method, are performed to reproduce three experimental cases, with the aim of isolating the different contributions of flap angle and trailing-edge/jet-axis distance h. The first case (DOAK), consisting of a single jet installed near a horizontal flat plate, confirms the fundamental mechanisms of jet-surface interaction and jet-surface reflection in the absence of lift. The second case (DLR-F16), with a coaxial jet installed under a high-lift wing, reveals the trailing-edge/jet-axis distance h as the dominant parameter, with a possible influence of the flap angle at low frequencies. The third case (SYMPHONY) is used to study the interaction of a coaxial jet with a full aircraft geometry using Fourier decomposition of the pressure near-field to analyse the effects on sound sources and radiation

    Monitoring and analysis of data in cyberspace

    Get PDF
    Information from monitored systems is displayed in three dimensional cyberspace representations defining a virtual universe having three dimensions. Fixed and dynamic data parameter outputs from the monitored systems are visually represented as graphic objects that are positioned in the virtual universe based on relationships to the system and to the data parameter categories. Attributes and values of the data parameters are indicated by manipulating properties of the graphic object such as position, color, shape, and motion

    Georgia's Aging Population: What to Expect and How to Cope

    Get PDF
    This report analyzes the impacts of Georgia's aging population on state finances. FRC Report 11

    The nutritional quality of organic and conventional food products sold in italy: Results from the food labelling of italian products (flip) study

    Get PDF
    The market for organic products is growing rapidly, probably attributable to the general customer perception that they are healthier foods, with a better nutritional profile than conventional ones. Despite this, the available studies show limited differences in the nutrient profile of organically and conventionally primary food products. Apart from this literature, no studies have focused on the nutrition profile of commercially prepacked foods. Thus, the aim of the present survey was to compare the nutritional quality intended as nutrition facts of organic and conventional prepacked foods sold in Italy. A total of 569 pairs of prepacked products (organic and their conventional counterparts) were selected from nine food categories sold by online retailers. By comparing organic and conventional products in the \u201cpasta, rice and other cereals\u201d category, the former were lower in energy, protein, and higher in saturates compared to the latter. Organic \u201cjams, chocolate spreads and honey\u201d products were lower in energy, carbohydrates, sugars and higher in protein than their regular counterparts. No differences were found for energy, macronutrients and salt for other categories. Therefore, based on the mandatory information printed on their packaging, prepacked organic products are not of a superior nutritional quality than conventional ones, with just a few exceptions. Consequently, the present study suggests that organic certification cannot be considered an indication of better overall nutritional quality. Further studies examining the nutritional quality of organic foods, taking into account the ingredients used, might better explain the results obtained

    Virtual reality and gamification in marketing higher education: A review and research agenda

    Get PDF
    Purpose – The purpose of this paper is to review studies on the use of virtual reality (VR) and gamification to engage students in higher education for marketing issues to identify the research topics, the research gaps and to prepare a future research agenda. Design/methodology/approach – A literature review is performed based on two search terms applied to Web of Science, resulting in a final pool of 115 articles. A text-mining approach is used to conduct a full-text analysis of papers related to VR and gamification in higher education. The authors also compare the salient characteristics presented in the articles. Findings – From this analysis, five major research topics are found and analysed, namely, teaching methodologies and education, experience and motivation, student engagement, applied theories in VR and gamification. Based on this and following the theory concept characteristics methodology framework, the paper provides directions for future research. Originality/value – There is no comprehensive review exploring the topics, theories, constructs and methods used in prior studies concerning VR and gamification applied to higher education services based on all the articles published in well-regarded academic journals. This review seeks to provide deeper insights, to help scholars contribute to the development of this research field.info:eu-repo/semantics/publishedVersio

    Notes on Recent Cases

    Get PDF
    Notes on recent cases by D. M. Donahue, A. J. DeDario, J. S. Angelino, J. J. Canty, F. Earl Lamboley, Marc Wonderlin, and Albion M. Griffin

    Combining real-time monitoring and knowledge-based analysis in MARVEL

    Get PDF
    Real-time artificial intelligence is gaining increasing attention for applications in which conventional software methods are unable to meet technology needs. One such application area is the monitoring and analysis of complex systems. MARVEL, a distributed monitoring and analysis tool with multiple expert systems, was developed and successfully applied to the automation of interplanetary spacecraft operations at NASA's Jet Propulsion Laboratory. MARVEL implementation and verification approaches, the MARVEL architecture, and the specific benefits that were realized by using MARVEL in operations are described

    Proteomics Analysis of Ovarian Cancer Cell Lines and Tissues Reveals Drug Resistance-associated Proteins

    Get PDF
    Background: Carboplatin and paclitaxel form the cornerstone of chemotherapy for epithelial ovarian cancer, however, drug resistance to these agents continues to present challenges. Despite extensive research, the mechanisms underlying this resistance remain unclear. Materials and Methods: A 2D-gel proteomics method was used to analyze protein expression levels of three human ovarian cancer cell lines and five biopsy samples. Representative proteins identified were validated via western immunoblotting. Ingenuity pathway analysis revealed metabolomic pathway changes. Results: A total of 189 proteins were identified with restricted criteria. Combined treatment targeting the proteasome-ubiquitin pathway resulted in re-sensitisation of drug-resistant cells. In addition, examination of five surgical biopsies of ovarian tissues revealed α-enolase (ENOA), elongation factor Tu, mitochondrial (EFTU), glyceraldehyde-3-phosphate dehydrogenase (G3P), stress-70 protein, mitochondrial (GRP75), apolipoprotein A-1 (APOA1), peroxiredoxin (PRDX2) and annexin A (ANXA) as candidate biomarkers of drug-resistant disease. Conclusion: Proteomics combined with pathway analysis provided information for an effective combined treatment approach overcoming drug resistance. Analysis of cell lines and tissues revealed potential prognostic biomarkers for ovarian cancer

    Nutritional quality of pasta sold on the italian market: The food labelling of italian products (FLIP) study

    Get PDF
    Pasta represents a staple food in many populations and, in recent years, an increasing number of pasta items has been placed on the market to satisfy needs and trends. The aims of this work were: (i) to investigate the nutritional composition of the different types of pasta currently sold in Italy by collecting the nutrition facts on their packaging; (ii) to compare energy, nutrient and salt content per 100 g and serving in fresh and dried pasta; (iii) to compare the nutrition declaration in pairs of products with and without different declarations (i.e., gluten free (GF), organic, and nutrition claims (NC)). A total of 756 items, made available by 13 retailers present on the Italian market, were included in the analysis. Data showed a wide difference between dried and fresh pasta, with high inter-type variability. A negligible amount of salt was observed in all types of pasta, except for stuffed products, which had a median high quantity of salt (>1 g/100 g and ~1.5 g/serving). Organic pasta had higher fibre and lower protein contents compared to conventional pasta. GF products were higher in carbohydrate and fat but lower in fibre and protein than not-GF products, while only a higher fibre content was found in pasta with NC compared to products not boasting claims. Overall, the results show high variability in terms of nutrition composition among the pasta items currently on the market, supporting the importance of reading and understanding food labels for making informed food choices

    A sensor aided H.264 encoder tested on aerial imagery for SFM

    Get PDF
    Email Print Request Permissions Standard video coding systems currently employed in UAV (Unmanned Aerial Vehicle) and aerial drone applications do not rely on some peculiarities in terms of scene 3D model and correlation among successive frames. In particular, the observed scene is static, i.e. the camera movement is dominant, and it can often be well approximated with a plane. Moreover, camera position and orientation can be obtained from the navigation system. Therefore, correspondent points on two video frames are linked by a simple homography. This paper presents novel results obtained by a low-complexity sensor aided H.264 encoder, recently developed at CIRA and yet tested on simulated data. The proposed encoder employs a new motion estimation scheme which make use of the global motion information provided by the onboard navigation system. The homography is used in order to initialize the block matching algorithm allowing a more robust motion estimation and a smaller search window, and hence reducing the complexity. The tests are made coding real aerial imagery, captured to be used for 3D scene reconstruction. The images are acquired by an high resolution camera mounted on a small drone, flying at low altitude
    • …
    corecore