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51.
Marina Contini Simone Baccelloni Maria Teresa Frangipane Nicolò Merendino Riccardo Massantini 《Journal of Functional Foods》2012,4(1):137-146
The simultaneous consumption of different classes of phytochemical antioxidants in the diet can result in more beneficial effects than when consumed alone. In the present study, the in vitro and in vivo antioxidative effects of espresso coffee brew (EC) (rich in chlorogenic acids) with added crude hazelnut skin phenolic extract (HSPE) from hazelnut skin waste (rich in flavonoids) were studied. Both post-brewing and pre-brewing phenolic-enriched espresso coffees (PE-ECs) were analysed for total phenols and screened for their in vitro antiradical ability. Moreover, the in vivo biological effect on the antioxidant potential of plasma in rats was evaluated. The PE-ECs showed increased both in vitro and in vivo antiradical activity proportional to the added HSPE. The in vivo experiments suggested that HSPE was much more antioxidant active than the phenolic fraction naturally contained in EC. Moreover, evidence of possible synergic effects of EC and HSPE phenolics was observed in vivo. 相似文献
52.
Matteo Rubagotti Marco Carminati Giampiero Clemente Riccardo Grassetti Antonella Ferrara 《Asian journal of control》2012,14(5):1159-1170
In this paper, an accurate model of an airbrake electro‐hydraulic smart actuator is obtained by physical considerations, and then different control strategies (variable‐gain proportional control, PT1 control with switching integrator, and second order sub‐optimal sliding mode control) are proposed and analyzed. This application is innovative in the avionic field, and is one of the first attempts to realize a fly‐by‐wire system for airbrakes, oriented to its immediate employment and installation on current aircraft. The project was carried on with the participation of the Italian Ministry of Defense, and was commissioned to MAG, a leading provider of integrated systems and aviation services for aerospace. Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
53.
54.
Aldo Todaro Francesco Cimino Paolo Rapisarda Anna E. Catalano Riccardo N. Barbagallo Giovanni Spagna 《Food chemistry》2009
Tartaric and malic acid solutions were tested to extract anthocyanins from eggplant peel by a discontinuous process to obtain a natural red colorant. Extraction optimization was carried out, using different solvents, acid concentration, temperature, time of extraction and solvent-to-solid ratio as independent variables. Tartaric acid was more efficient than malic acid in both extraction yield and rate. Comparative tests were carried out using acidified ethanol as solvent. Delphinidin-3-rutinoside was extracted and identified as the major anthocyanin in eggplant peel. Concentration of different extracts from eggplant peel was carried out using EXA-31, a methacrylic food grade resin, the best performing resin to obtain highly concentrated extracts. 相似文献
55.
Alessandro Abbotto Erika Herrera Calderon Norberto Manfredi Claudio Maria Mari Chiara Marinzi Riccardo Ruffo 《Synthetic Metals》2011,161(9-10):763-769
Vinylene-linked donor–acceptor–donor semiconducting polymers have been prepared by electropolymerization of the new monomers 2,6-bis[(E)-2-(1-methylpyrrol-2-yl)vinyl]pyridine and 2,5-bis[(E)-2-(1-methylpyrrol-2-yl)vinyl]pyridine. The monomers, consisting of two pyrrole donor units and a central pyridine acceptor ring spaced by vinylene links, differ by the substitution pattern around the central pyridine core (2,6 vs. 2,5-substitution). The electropolymerization process is more efficient on the 2,5-derivative. The new polymers show reversible electrochemistry dominated by a strong charge trapping effect. Poly(2,5-bis[(E)-2-(1-methylpyrrol-2-yl)vinyl]pyridine) energy levels closely match those of design rules for optimized polymers in combination with fullerene derivatives in bulk heterojunction solar cells. 相似文献
56.
Andr Neto Filippo Sartori Fabio Piccolo Antonio Barbalace Riccardo Vitelli Horcio Fernandes JET-EFDA 《Fusion Engineering and Design》2009,84(7-11):1408-1411
A new framework for the development and execution of real-time codes is currently being developed and commissioned at JET. The foundations of the system are Linux, the Real Time Application Interface (RTAI) and a wise exploitation of the new i386 multi-core processors technology.The driving motivation was the need to find a real-time operating system for the i386 platform able to satisfy JET Vertical Stabilisation Enhancement project requirements: 50 μs cycle time. Even if the initial choice was the VxWorks operating system, it was decided to explore an open source alternative, mostly because of the costs involved in the commercial product.The work started with the definition of a precise set of requirements and milestones to achieve: Linux distribution and kernel versions to be used for the real-time operating system; complete characterization of the Linux/RTAI real-time capabilities; exploitation of the multi-core technology; implementation of all the required and missing features; commissioning of the system.Latency and jitter measurements were compared for Linux and RTAI in both user and kernel-space. The best results were attained using the RTAI kernel solution where the time to reschedule a real-time task after an external interrupt is of 2.35 ± 0.35 μs. In order to run the real-time codes in the kernel-space, a solution to provide user-space functionalities to the kernel modules had to be designed. This novel work provided the most common functions from the standard C library and transparent interaction with files and sockets to the kernel real-time modules. Kernel C++ support was also tested, further developed and integrated in the framework.The work has produced very convincing results so far: complete isolation of the processors assigned to real-time from the Linux non real-time activities, high level of stability over several days of benchmarking operations and values well below 3 μs for task rescheduling after external interrupt. From being the alternative option, RTAI has been finally chosen as the platform for the project. A first stable version of the framework has been integrated on the JET system and is already being commissioned. It will be soon be used on the Vertical Stabilisation Enhancement for the Plasma Control Upgrade (PCU) project at JET. 相似文献
57.
Paola Bonizzoni Gianluca Della Vedova Riccardo Dondi Giancarlo Mauri 《Algorithmica》2010,58(2):282-303
The problem of clustering fingerprint vectors with missing values is an interesting problem in Computational Biology that
has been proposed in Figueroa et al. (J. Comput. Biol. 11(5):887–901, 2004). In this paper we show some improvements in closing the gaps between the known lower bounds and upper bounds on the approximability
of variants of the biological problem. Moreover, we have studied two additional variants of the original problem proposed
in Figueroa et al. (Proc. 11th Computing: The Australasian Theory Symposium (CATS), CRPIT, vol. 41, pp. 57–60, 2005). We prove that all such problems are APX-hard even when each fingerprint contains only two unknown positions and we present
a greedy algorithm that has constant approximation factors for these variants. Despite the hardness of these restricted versions
of the problem, we show that the general clustering problem on an unbounded number of missing values such that they occur
for every fixed position of an input vector in at most one fingerprint is polynomial time solvable. 相似文献
58.
Carotenuto R Sabbi G Pappalardo M 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2002,49(8):1039-1049
Spatial resolution in modern ultrasound imaging systems is limited by the high cost of large aperture transducer arrays, which require a large number of transducer elements and electronic channels. A new technique to enhance the spatial resolution of pulse-echo imaging systems is presented. The method attempts to build an image that could be obtained with a transducer array aperture larger than that physically available. We consider two images of the same object obtained with two different apertures, the full aperture and a subaperture, of the same transducer. A suitable artificial neural network (ANN) is trained to reproduce the relationship between the image obtained with the transducer full aperture and the image obtained with a subaperture. The inputs of the neural network are portions of the image obtained with the subaperture (low resolution image), and the target outputs are the corresponding portions of the image produced by the full aperture (high resolution image). After the network is trained, it can produce images with almost the same resolution of the full aperture transducer, but using a reduced number of real transducer elements. All computations are carried out on envelope-detected decimated images; for this reason, the computational cost is low and the method is suitable for real-time applications. The proposed method was applied to experimental data obtained with the ultrasound synthetic aperture focusing technique (SAFT), giving quite promising results. Realtime implementation on a modern, full-digital echographic system is currently being developed. 相似文献
59.
Francesco Bellotti Riccardo Berta Alessandro De Gloria Massimiliano Margarone 《Personal and Ubiquitous Computing》2002,6(3):155-163
Future generation cars will be characterized by a wide range of Information Technology (IT) services providing safety and
infotainment. This makes the car an information intensive environment where the visual channel is overloaded, putting the
safety of drivers and passengers in jeopardy. We propose the use of a 3D auditory display to provide information from the
Advanced Driver Assistance Systems. This reduces the eye-off-road time, exploiting the human capability to associate sounds
with positions in space. Preliminary lab tests reveal the suitability of this approach. The system still has to be carefully
tuned and personalized to achieve usability and reliability, but we think that it provides a complementary channel that is
specially useful in low visibility conditions. 相似文献
60.
Materials and Structures - The determination of mortar load capacity in masonryin situ is not an established technique. An indirect method is described in this paper and, like the earlier one by... 相似文献