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71.
Useful model checking tools can be constructed by measuring the distance between a prior distribution that concentrates most of its mass around a model of interest, and the resulting posterior distribution. In this paper we use this approach to construct a diagnostic measure for detecting lack of fit in discrete data, with special focus on binomial data. We begin by constructing a suitable probability model “around” the model of interest, via a Dirichlet Process elaboration. We derive the resulting diagnostic and show that, approximately, it is the sum of two terms: the first is the logarithm of the Bayes factor and the second is proportional to the Pearson chi-square statistics. We give details of a simulation algorithm for computing the diagnostic and illustrate its use in an application to biomedical data.  相似文献   
72.
This paper aims at being a comprehensive reference for stakeholders, policy makers, and scholars interested in analyzing the problem of efficiency, effectiveness, and impacts of rail transport systems in a sound empirical way, paying specific attention to passenger transport services. The paper combines different analytical frameworks (engineering, economics, impacts), systematic review techniques, and advanced mappings. Framing economic efficiency studies into a transport planning perspective permits to move from efficiency to effectiveness issues. In addition, including impacts offers a critical discussion of the existing empirical studies, relating them to the main methodological approaches used. This analysis can be useful for those interested in developing new techniques for the evaluation of this sector. The critical analysis developed in this paper provides a catalog of inputs, outputs, external factors, possible impacts to account for, data, and approaches, which allows us to identify areas in which new methodological developments, new approaches, are needed to address the relevant societal challenges of the rail transport sector.  相似文献   
73.
This paper presents an approach for enhancing the design phase of AUTOSAR models when security annotations are required. The approach is based on information flow analysis and abstract interpretation. The analysis evaluates the correctness of the model by assessing if the flow of data is secure with respect to causal data dependencies within the model. To find these dependencies an exhaustive search through the model would be required. Abstract interpretation is used as a trade-off between the precision and complexity of the analysis. The approach also provides annotated models without oversizing the set of annotations.  相似文献   
74.
As the ASIC design cost becomes affordable only for very large-scale productions, the FPGA technology is currently becoming the leading technology for those applications that require a small-scale prod...  相似文献   
75.
In this investigation, silica aerogel (SA)/Rigid Polyurethane (PUR) foam composites and silica aerogel/Polyurethane (PU) composites were prepared by dry mixing of granular and grinded silica aerogels with polyol part. They were then combined with diisocyanate part. Three different types of PUR foams and an elastomeric coating grade of PU were studied as well. Results show that thermal conductivity of foams did not decrease by adding silica aerogel. It even increased for some grades which is assumed to be due to the change in cell configuration of these foams. It was also found that sound insulation performance of these cellular composites did not improve significantly. Unlike foam composites, addition of silica aerogel into elastomeric PU improved its thermal and acoustic insulation properties. Because of the more promising properties of elastomeric PU composites, further examinations including measurements of compression strength and water contact angle of silica aerogel/PU composites were also taken. Final results showed a significant improvement in general properties of PU coatings by adding little amounts of silica aerogel (1–4 wt %). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44521.  相似文献   
76.
77.
Giovanni Ambrosi  Simona Bartocci  Laurent Basara  Roberto Battiston  William J. Burger  Luca Carfora  Guido Castellini  Piero Cipollone  Livio Conti  Andrea Contin  Cinzia De Donato  Cristian De Santis  Francesco M. Follega  Cristina Guandalini  Maria Ionica  Roberto Iuppa  Giuliano Laurenti  Ignazio Lazzizzera  Mauro Lolli  Christian Manea  Laura Marcelli  Giuseppe Masciantonio  Matteo Mergé  Giuseppe Osteria  Lorenzo Pacini  Francesco Palma  Federico Palmonari  Beatrice Panico  Laura Patrizii  Francesco Perfetto  Piergiorgio Picozza  Michele Pozzato  Matteo Puel  Irina Rashevskaya  Ester Ricci  Marco Ricci  Sergio Bruno Ricciarini  Valentina Scotti  Alessando Sotgiu  Roberta Sparvoli  Bruno Spataro  Vincenzo Vitale 《中国科学:技术科学(英文版)》2018,61(5):643-652
CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle environment, for studying the seismo-associated disturbances in the ionosphere-magnetosphere transition zone. The anthropogenic and electromagnetic noise,as well as the natural non-seismic electromagnetic emissions is mainly due to tropospheric activity. In particular, the mission aims to confirming the existence of possible temporal correlations between the occurrence of earthquakes for medium and strong magnitude and the observation in space of electromagnetic perturbations, plasma variations and precipitation of bursts with highenergy charged particles from the inner Van Allen belt. In this framework, the high energy particle detector(HEPD) of the CSES mission has been developed by the Italian LIMADOU Collaboration. HEPD is an advanced detector based on a tower of scintillators and a silicon tracker that provides good energy and angular resolution and a wide angular acceptance, for electrons of 3–100 Me V, protons of 30–200 Me V and light nuclei up to the oxygen. CSES satellite has been launched on February 2~(nd), 2018 from the Jiuquan Satellite Launch Center(China).  相似文献   
78.
Scientometrics - The quantitative evaluation of Social Science and Humanities (SSH) and the investigation of the existing similarities between SSH and Life and Hard Sciences (LHS) represent the...  相似文献   
79.
Motor neuron diseases (MNDs) are neurodegenerative disorders characterized by upper and/or lower MN loss. MNDs include amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA), and spinal and bulbar muscular atrophy (SBMA). Despite variability in onset, progression, and genetics, they share a common skeletal muscle involvement, suggesting that it could be a primary site for MND pathogenesis. Due to the key role of muscle-specific microRNAs (myomiRs) in skeletal muscle development, by real-time PCR we investigated the expression of miR-206, miR-133a, miR-133b, and miR-1, and their target genes, in G93A-SOD1 ALS, Δ7SMA, and KI-SBMA mouse muscle during disease progression. Further, we analyzed their expression in serum of SOD1-mutated ALS, SMA, and SBMA patients, to demonstrate myomiR role as noninvasive biomarkers. Our data showed a dysregulation of myomiRs and their targets, in ALS, SMA, and SBMA mice, revealing a common pathogenic feature associated with muscle impairment. A similar myomiR signature was observed in patients’ sera. In particular, an up-regulation of miR-206 was identified in both mouse muscle and serum of human patients. Our overall findings highlight the role of myomiRs as promising biomarkers in ALS, SMA, and SBMA. Further investigations are needed to explore the potential of myomiRs as therapeutic targets for MND treatment.  相似文献   
80.
A thermochemical water-splitting cycle representing a modification of the classical sulphur–iodine cycle is proposed. To decrease the energetic demand, increasing the cycle energy efficiency, the distillation of the iodine phase was replaced with the evaporation of the excess of water and iodine. This was obtained by neutralizing the hydrogen iodide in the iodine phase with nickel oxide. In such a way water and iodine can be simply recovered by evaporation leaving nickel iodide as solid phase. The nickel iodide is decomposed to obtain nickel metal and hydrogen is produced by reaction of the metal with sulphuric acid. The nickel sulphate, obtained after hydrogen production, is decomposed to generate sulphur dioxide (used as the reagent in the Bunsen reaction) and nickel oxide (that is recycled). To validate the cycle effectiveness the proposed reactions have been carried out. Crystalline solid materials have been identified by XRD diffraction. Powders morphology was studied by scanning electron microscopy and energy dispersive X-ray. Thermodynamics studies were carried out by thermogravimetric and differential thermal analysis. Finally an energy balance to evaluate the theoretical energy efficiency was computed.  相似文献   
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