1,450 research outputs found

    High resolution satellite imagery orientation accuracy assessment by leave-one-out method: accuracy index selection and accuracy uncertainty

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    The Leave-one-out cross-validation (LOOCV) was recently applied to the evaluation of High Resolution Satellite Imagery orientation accuracy and it has proven to be an effective method alternative with respect to the most common Hold-out-validation (HOV), in which ground points are split into two sets, Ground Control Points used for the orientation model estimation and Check Points used for the model accuracy assessment. On the contrary, the LOOCV applied to HRSI implies the iterative application of the orientationmodel using all the known ground points as GCPs except one, different in each iteration, used as a CP. In every iteration the residual between imagery derived coordinates with respect to CP coordinates (prediction error of the model on CP coordinates) is calculated; the overall spatial accuracy achievable from the oriented image may be estimated by computing the usual RMSE or, better, a robust accuracy index like the mAD (median Absolute Deviation) of prediction errors on all the iterations. In this way it is possible to overcome some drawbacks of the HOV: LOOCVis a reliable and robustmethod, not dependent on a particular set of CPs and on possible outliers, and it allows us to use each known ground point both as a GCP and as a CP, capitalising all the available ground information. This is a crucial problem in current situations, when the number of GCPs to be collected must be reduced as much as possible for obvious budget problems. The fundamentalmatter to deal with was to assess howwell LOOCVindexes (mADand RMSE) are able to represent the overall accuracy, that is howmuch they are stable and close to the corresponding HOV RMSE assumed as reference. Anyway, in the first tests the indexes comparison was performed in a qualitative way, neglecting their uncertainty. In this work the analysis has been refined on the basis of Monte Carlo simulations, starting from the actual accuracy of ground points and images coordinates, estimating the desired accuracy indexes (e.g. mAD and RMSE) in several trials, computing their uncertainty (standard deviation) and accounting for them in the comparison. Tests were performed on a QuickBird Basic image implementing an ad hoc procedure within the SISAR software developed by the Geodesy and Geomatics Team at the Sapienza University of Rome. The LOOCV method with accuracy evaluated by mAD seemed promising and useful for practical case

    Application of the analytical hierarchy process to evaluate consumer acceptance and preferences for omega-3 enriched eggs

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    Purpose: The purpose of this paper is to analyse the appropriateness of the analytical hierarchy process (AHP) to measure consumers’ acceptance and preference for eggs enriched with omega-3 (n-3) fatty acids as a health claim and to compare its results with the traditional nine-point hedonic scale. Design/methodology/approach: The AHP was used as a multi-criteria decision analysis. Data were obtained from a face-to-face questionnaire completed by 122 consumers in a controlled environment in Cataluña (Spain). Findings: Results showed the capacity of the AHP to analyse consumers’ acceptance and preferences. An agreement between the AHP and the nine-point scale was found showing that n-3 enriched eggs had lower flavour acceptance, conventional eggs had higher yolk colour acceptance, and conventional and the free-range eggs had similar and higher odour acceptance than the other egg types. The most important attributes that determine preferences for egg purchase were the type and the egg price followed by the origin and the egg size. Research limitations/implications: The AHP approach seems to be a reliable tool to evaluate consumers’ hedonic preferences. However, further testing on other food products with larger sample size is needed. Originality/value: The AHP methodology has been widely used in many fields in the last decades, but to the knowledge, not in the sensory field. In the Spanish market, studies that analyse consumers’ preferences and acceptance of eggs are scarce, and new insights are needed particularly regarding n-3 enriched eggs.Postprint (author's final draft

    Role of endocannabinoids in regulating drug dependence

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    This review will discuss the latest knowledge of how the endocannabinoid system might be involved in treating addiction to the most common illicit drugs. Experimental models are providing increasing evidence for the pharmacological management of endocannabinoid signaling not only to block the direct reinforcing effects of cannabis, opioids, nicotine and ethanol, but also for preventing relapse to the various drugs of abuse, including opioids, cocaine, nicotine, alcohol and metamphetamine. Preclinical and clinical studies suggest that the endocannabinoid system can be manipulated by the CBI receptor antagonist SR141716A, that might constitute a new generation of compounds for treating addiction across different classes of abused drugs

    Key performance indicators of ‘good practices’ of energy efficiency in industry: application to real cases in Italy and in the European Union

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    With the publication of the Energy Efficiency Directive (EED) in 2012, energy savings in the Industry processes have gained more and more importance in the European Union (EU). Industry (with building and transport) is one of the three main sectors where Energy consumption and efficiency play a fundamental role, to accomplish the EU energy objectives. Many countries in EU have already adopted schemes and mechanisms to implement the Directive: however deep differences of approaches still remain among the Member States (MSs), especially with respect to the identification of the real benefits of measures and to the assessment of their efficiency and sustainability. As a consequence, a huge amount of the efficiency potential still remains untapped. This paper proposes some criteria for the evaluation of the applied Energy Efficiency measures, leading to the identification of Good Practices of Energy Efficiency. These criteria are taken from the ‘real world’ of industry, and are susceptible to be replicated in other contexts (e.g. different sectors or other countries). The proposed criteria have been developed in the EU H2020 project EU MERCI (nr 693845) and through a national research (part of the ‘Ricerca di Sistema’ national funding system) both coordinated by RSE. The starting point is the harmonization of data sets related to projects developed in different EU countries within local efficiency implementation schemes. The second step is the definition of Key Performance Indicators (KPIs) reflecting the impact of measures against Energy, Environment and Economic aspects. The last step is the extraction of efficiency ‘Good Practices’ ranked according to the identified KPIs and other factors, including social elements. The real added value of this approach is that it is full based on tangibly implemented projects, in opposition to similar attempts, essentially theoretical. Ultimately, it offers a key of assessment of the effectiveness of efficiency measures implementing local and EU policies

    High-precision GPS survey of Via Appia: Archaeoastronomy-related aspects

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    Via Appia was built by the Romans around 312 BCE to connect Rome with Capua during the Samnite wars. The road is an astonishing engineering masterpiece. In particular, the segment which runs from Collepardo to Terracina – 61 km long – is renowned for being virtually straight; however this “straightness” was never investigated quantitatively. As a consequence, the techniques used by the ancient surveyors and their scope – whether it was only practical, or also symbolic – remain obscure. We report here a high-precision GPS survey of the road, performed with a u-blox receiver and further checked with a dual frequency receiver. We give a detailed analysis of the methods used and of the errors, which are shown to be less than 6’. To our knowledge it is the first time that such a long ancient manufactured structure has been surveyed with such a high accuracy. The results lead us to conclude that astronomy was certainly used in the construction of the road and in that of the associated grid, oriented to the setting of the star Castor and to the cardinal points respectively
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