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971.
Most complex information systems are event driven: each part of the system reacts to the events happening in the other parts, potentially generating new events. Complex event processing (CEP) engines in charge of interpreting, filtering, and combining primitive events to identify higher level composite events according to a set of rules are the new breed of message-oriented middleware, which is being proposed today to better support event-driven interactions. 相似文献
972.
Paolo Colomba Simona Fontana Giuseppe Salemi Marilisa Barranca Claudia Lo Sicco Maria Antonietta Mazzola Paolo Ragonese Giovanni Savettieri Giacomo De Leo Riccardo Alessandro Giovanni Duro 《International journal of molecular sciences》2014,15(12):23269-23282
Multiple sclerosis (MS) is an autoimmune inflammatory demyelinating disease of the central nervous system. At present, the molecular mechanisms causing the initiation, development and progression of MS are poorly understood, and no reliable proteinaceous disease markers are available. In this study, we used an immunoproteomics approach to identify autoreactive antibodies in the cerebrospinal fluid of MS patients to use as candidate markers with potential diagnostic value. We identified an autoreactive anti-transferrin antibody that may have a potential link with the development and progression of MS. We found this antibody at high levels also in the serum of MS patients and created an immunoenzymatic assay to detect it. Because of the complexity and heterogeneity of multiple sclerosis, it is difficult to find a single marker for all of the processes involved in the origin and progression of the disease, so the development of a panel of biomarkers is desirable, and anti-transferrin antibody could be one of these. 相似文献
973.
Michele SalePiervincenzo Rizzo Alessandro Marzani 《Mechanical Systems and Signal Processing》2011,25(6):2241-2256
In this study an inverse procedure based on the propagation of guided ultrasonic waves is proposed for the characterization of the elastic material constants of plates. The procedure consists of an optimization problem in which the discrepancy between the dispersion curves obtained through a semi analytical finite element (SAFE) formulation and numerical or experimental dispersion curves is minimized. The numerical dispersion curves were obtained from the application of the commercial finite element analysis software ANSYS. Finally experimental data were obtained by adopting a hybrid broadband laser/PZT ultrasonic set-up in a pitch-catch configuration. For both numerical and experimental data, the joint time-frequency analysis of the continuous wavelet transform was used.The optimization scheme proposed in this study is based on an improved version of the simplex search method. The scheme inputs an initial guess of the material parameters in the SAFE formulation. The values of these parameters are iteratively updated until the discrepancy between the SAFE-based group velocity dispersion curves and the numerical or experimental curves is minimized. The scheme is designed to minimize the discrepancy associated with the lowest symmetric and anti-symmetric order mode simultaneously.The validity of the SAFE method coupled to the inverse procedure scheme is tested to characterize the elastic material properties of a 2.54 mm thick aluminum plate. As the SAFE formulation is valid for waveguides of arbitrary cross-section the paper represents the first step toward the integration of an inversion scheme applicable into the SAFE algorithm to characterize the material properties of waveguides of complex geometries and various boundary conditions. 相似文献
974.
Renato Queiroz Assis Carlos Henrique Pagno Tania Maria Haas Costa Simone Hickmann Fl?res Alessandro de Oliveira Rios 《软包装商情》2018,(3)
β-胡萝卜素可能是一种优良的天然抗氧化剂,可能有助于纳米封装新技术的发展为主动包装添加抗氧化剂。这项工作的目的是开发加自由β-胡萝卜素或β-胡萝卜素胶囊和与聚合物基体的相互作用的评估活动的可生物降解薄膜。结果表明,生物活性化合物可以作为天然抗氧化剂和疏水活性可降解包装维护食品安全添加。 相似文献
975.
Nowadays, manufacturing firms are dealing with the unpredictability of market requirements and the frequent changes induced by technological innovation. For this reason, firms are more and more addressing the need to be responsive at an affordable cost. To do so, they are required to develop a capability called reconfigurability. This paper is a review of the existing literature because the current need makes interesting to reflect on the state of the art of reconfigurability as a concept. This reflection has led to focus on reconfigurability characteristics for both their relevance and their relationships with managerial decisions in manufacturing. To this end, a framework has been proposed. It is based on system lifecycle and production levels. These two elements have been deduced from literature and identified as relevant dimensions for decision-making. 相似文献
976.
In recent years, the performance of deep neural networks (DNNs) is significantly improved, making them suitable for many application fields, such as autonomous driving, advanced robotics, and industrial control. Despite a lot of research being devoted to improving the accuracy of DNNs, only limited efforts have been spent to enhance their timing predictability, required in several real-time applications. This paper proposes a software infrastructure based on the Linux operating system to integrate DNNs within a real-time multicore system. It has been realized by modifying both the internal scheduler of the popular TensorFlow framework and the SCHED_DEADLINE scheduling class of Linux. The proposed infrastructure allows providing timing isolation of DNN inference tasks, hence improving the determinism of the temporal interference generated by TensorFlow. The proposal is finally evaluated with a case study derived from a state-of-the-art benchmark inspired by an autonomous industrial system. Extensive experiments demonstrate the effectiveness of the proposed solution and show a significant reduction of both average and longest-observed response times of TensorFlow tasks. 相似文献
977.
Grappa quality from the Chianti and Montepulciano areas (Tuscany,Italy): monitoring the leaching of copper from distillation columns
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Gabriella Tamasi Alessandro Donati Gemma Leone Agnese Magnani Renzo Cini Eugenio Macchia Claudio Rossi Claudia Bonechi 《International Journal of Food Science & Technology》2018,53(6):1558-1565
The main aim of this work was to evaluate the leaching of copper in grappa from distillation plant that treats Cabernet and Sangiovese marcs (Montepulciano and Chianti, Tuscany). Copper content (determined by atomic absorption spectrometry, AAS) was 1.05 ± 0.03 mg L?1 in industrial distillates (Cabernet marc, 82.3% alcohol, v/v), and 3.7 ± 0.2 μg L?1 in artificial grappa (62.0%, Cabernet) obtained by distilling marc in a laboratory‐scale glassware plant. The artificial grappa distillate was refluxed over copper shavings, and copper content, CCu, was analysed in relation to reflux time and wear of the copper bell. The results showed that CCu trend was almost linear with increasing alcohol concentration and constant reflux time, and vice versa. The ratios of selected volatile components were not influenced by reflux on the shavings. 相似文献
978.
ABSTRACT The financial crisis has caused many business closures, especially in the periphery of the European Monetary Union. In this paper, we use original firm-level Italian data to explore the role of intangibles in limiting firm exit during the crisis. While intangibles strengthen firms’ resilience, i.e. the ability to cope with unexpected shocks, they also entail sunk costs, which expose firms to greater financial risk. In the longer term, when access to external finance is critical for survival, we expect intangibles to play a positive role only if combined with a solid financial structure. Our results support these hypotheses: intangibles directly reduce the probability of firm exit during the initial phase of the crisis (before 2010). At later stages, the beneficial effect of intangible assets is conditional on the firm exhibiting a solid pre-crisis financial status. Managerial and policy implications are discussed. 相似文献
979.
Marco Girolami Alessandro Bellucci Matteo Mastellone Stefano Orlando Andrea Orsini Stefano Salvatori Daniele M. Trucchi 《Ceramics International》2019,45(7):9544-9547
Surface nanostructured diamond films by ultrashort pulse laser treatment, named black diamond, demonstrated a huge increase in the photogeneration capability for photons with sub-bandgap energy (<5.47?eV). Here we analyze in detail the transport properties of photogenerated charge carriers in several black diamond samples, in order to better understand the electronic behavior of defect levels introduced by the laser treatment. If compared with the pristine diamond films, the mean charge carriers’ mobility-lifetime product, evaluated from the over bandgap photocurrent characteristics, remarkably increases in every black diamond set up to a defined absorbed accumulated laser fluence before decreasing at the highest fluence values. We attribute this effect to the laser-induced introduction of fast traps for one charge carrier type, that increases with fluence. At the same time, an increasing density of recombination centers, capturing permanently the charge carriers, is formed. A trade-off treatment condition can be found in order to maximize the sensitivity to sub-bandgap photons and the mean mobility-lifetime product as well as to limit the effect of recombination centers. 相似文献
980.
Aurelio Mauri Salvatore M. Amoroso Christian Monzio Compagnoni Alessandro Maconi Alessandro S. Spinelli 《Solid-state electronics》2011,56(1):23-30
A new non-local algorithm for accurately calculating the band-to-band tunneling current suitable for TCAD semiconductor simulators is proposed in this paper. The proposed algorithm captures the essential physics of multi-dimensional tunneling in a 2D structure, and is designed to be robust and to achieve independence on the mesh grid. The new algorithm enables accurate modeling of T-FET and investigation of its device physics. 相似文献