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31.
Artistic edge and corner enhancing smoothing. 总被引:1,自引:0,他引:1
Giuseppe Papari Nicolai Petkov Patrizio Campisi 《IEEE transactions on image processing》2007,16(10):2449-2462
Two important visual properties of paintings and painting-like images are the absence of texture details and the increased sharpness of edges as compared to photographic images. Painting-like artistic effects can be achieved from photographic images by filters that smooth out texture details, while preserving or enhancing edges and corners. However, not all edge preserving smoothers are suitable for this purpose. We present a simple nonlinear local operator that generalizes both the well known Kuwahara filter and the more general class of filters known in the literature as "criterion and value filter structure." This class of operators suffers from intrinsic theoretical limitations which give rise to a dramatic instability in presence of noise, especially on shadowed areas. Such limitations are discussed in the paper and overcome by the proposed operator. A large variety of experimental results shows that the output of the proposed operator is visually similar to a painting. Comparisons with existing techniques on a large set of natural images highlight conditions on which traditional edge preserving smoothers fail, whereas our approach produces good results. In particular, unlike many other well established approaches, the proposed operator is robust to degradations of the input image such as blurring and noise contamination. 相似文献
32.
James S. Bendall Marzia Paderi Francesca Ghigliotti Nello Li Pira Vitoguido Lambertini Vladimir Lesnyak Nikolai Gaponik Giuseppe Visimberga Alexander Eychmüller Clivia M. Sotomayor Torres Mark E. Welland Christina Gieck Leonardo Marchese 《Advanced functional materials》2010,20(19):3298-3302
A novel all‐inorganic electroluminescent device is demonstrated based on highly luminescent CdTe nanocrystals intercalated within a laminar hydrotalcite‐like structure. The laminar scaffold acts to both support and distribute the CdTe nanocrystals. The device is synthesized using simple wet chemical processes at room temperature in ambient conditions. It has high thermal stability, operating continuously up to 90 °C, and a maximum efficiency at J = 0.12 A cm?2. The device is targeted at the automotive industry. 相似文献
33.
Junction leakage current degradation under high temperature reverse-bias stress induced by band-defect-band tunnelling in power VDMOS 总被引:2,自引:0,他引:2
A deep analysis of the intrinsic junction and surface currents in power vertically diffused MOS devices with sub-micrometer channel length and thin gate oxide has been carried on after a typical reliability high temperature reverse bias (HTRB) stress. A reference set of gated diodes has also been examined in order to better understand the onset and evolution of post-stress leakage degradation. A comparison among complete MOSs, single body diodes and enriched diodes allows to highlight the role played by the point defectivity both at gate interface and in the bulk silicon close to the junction surface. We found that the typical interface defects involved in the leakage degradation are shallow traps and can be de-populated simply by a thermally activated mechanism. More specifically, the main degradation mechanism relies to band-defect-band tunneling localized at the surface drain/body junction where an intrinsic n-i-p region evolves due to a bird’s beak lateral profile of the body diffusion. We have demonstrated that the most important contribution to the activation of the precursor defect sites is given by the transverse electrical field that develops just below the SiO2/Si interface within the n-i-p region during the stress. 相似文献
34.
35.
Francesco Malara Alessandro Cannavale Giuseppe Gigli 《Progress in Photovoltaics: Research and Applications》2015,23(3):290-301
In the last few years, a new class of smart multifunctional photoelectrochemical devices has been attracting the interest of several academic institutions and industrial companies: photovoltachromic cells, combining the features of photoelectrochromic cells with those of dye‐sensitized solar cells. Here, we report the results of a detailed electrochemical analysis aiming at investigating the electrochemical behavior of these complex photoelectrochemical devices. In particular, we have been focused on the effect of Li+ ions displacement during the coloration of the electrochromic tungsten oxide on the performances of the photovoltaic unit. As we had previously observed striking differences between the performances of the barely photovoltaic mode (with the tungsten oxide in the bleached state) and the photovoltachromic mode (with the tungsten oxide in the colored state), we thus attempted to provide a reasonable physical interpretation to the observed phenomena. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
36.
Nicholas D. Lane Mu Lin Mashfiqui Mohammod Xiaochao Yang Hong Lu Giuseppe Cardone Shahid Ali Afsaneh Doryab Ethan Berke Andrew T. Campbell Tanzeem Choudhury 《Mobile Networks and Applications》2014,19(3):345-359
Smartphone sensing and persuasive feedback design is enabling a new generation of wellbeing apps capable of automatically monitoring multiple aspects of physical and mental health. In this article, we present BeWell+ the next generation of the BeWell smartphone wellbeing app, which monitors user behavior along three health dimensions, namely sleep, physical activity, and social interaction. BeWell promotes improved behavioral patterns via feedback rendered as an ambient display on the smartphone’s wallpaper. With BeWell+, we introduce new mechanisms to address key limitations of the original BeWell app; specifically, (1) community adaptive wellbeing feedback, which generalizes to diverse user communities (e.g., elderly, children) by promoting better behavior yet remains realistic to the user’s lifestyle; and, (2) wellbeing adaptive energy allocation, which prioritizes monitoring fidelity and feedback responsiveness on specific health dimensions (e.g., sleep) where the user needs additional help. We evaluate BeWell+ with a 27 person, 19 day field trial. Our findings show that not only can BeWell+ operate successfully on consumer smartphones; but also users understand feedback and respond by taking steps towards leading healthier lifestyles. 相似文献
37.
38.
Opening Doors to Future Electrochemical Energy Devices: The Anion‐Conducting Polyketone Polyelectrolytes 下载免费PDF全文
Graeme Nawn Keti Vezzù Gianni Cavinato Giuseppe Pace Federico Bertasi Gioele Pagot Enrico Negro Vito Di Noto 《Advanced functional materials》2018,28(29)
The numerous potential benefits of incorporating anion‐exchange membranes (AEMs), in place of proton‐exchange membranes (PEMs), in energy storage and conversion technologies renders their development of fundamental importance for the continued evolution of alternative energy systems. However, the widespread implementation of AEMs is currently plagued by a range of problems including lower conductivity (with respect to PEMs), poor stability, and high cost. This study reports the conversion of polyketone, one of the world's most mass produced and cheap polymers, to a new highly tuneable polymer architecture, functionalized polyketone (FPK), that demonstrates a range of excellent properties rendering it a significant prospect for AEM materials. The thermal, processing, and ion‐conducting properties of FPK are governed by the amount and nature of the newly formed N‐substituted pyrrole pendant side groups. At 80 °C, the quarternized pyridyl FPK derivative (4MPyrFPK) yields ion‐conductivities of 8.6 and 10.5 mS cm?1 in the iodide and hydroxide forms. In addition, the hydroxide form of 4MPyr‐FPK demonstrates remarkable stability toward the typically problematic alkaline conditions. No chemical decomposition is observed to the membrane after imbibing it in KOH solution for 72 h, and furthermore, the ion‐conductivity is demonstrated to remain constant for at least 30 d at 80 °C. 相似文献
39.
Different designs of solar air heaters with variable width of the flow channels are investigated.
Four possible geometries for the flow passage are considered with the aim to improve the efficienc of the system by maintaining a constant temperature of the absorber plate.
Efficiencies and plate temperatures are calculated for various designs, among them the most efficient is the one with decreasing duct width. 相似文献
40.
Ambrogio Monetti Fabiano Reniero Giuseppe Versini 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1994,199(4):311-316
The site-specific natural isotope fractionationnuclear magnetic resonance (SNIF-NMR)2H analysis is at present the reference method for determining the origin of ethanol and has been successfully applied for analysing all grape products. The method has also been used to identify the origin of wines and the aim of this study was to verify this application. In all, 3309 samples belonging to the Italian wines data bank were analysed from all 20 Italian regions to study the possibilities of determining and controlling the exact origin and year of the product. The dependency of the deuterium/hydrogen ratio of the methyl site (D/HI) with latitude was confirmed but this was not the case for the D/H ratio of the methylene site (D/HII) and the parameter R [2(D/HII)/(D/HI)] did not add any additional information. The frequency distribution of the NMR parameters follows a regular North-South gradient but they are not sufficiently different in each region to allow unique characterisation. The lack of effectiveness of the method, when applied to identification, depends on interannual and interregional variability. As a consequence, all but some very different regions overlap. The SNIF-NMR method is particularly suitable for detecting simple adulterations but, in the Italian situation, seems not to be so useful for solving problems of geographical origin. For this, it could be helpful to use other isotopic parameters and to ameliorate the sampling technique, to improve the effectiveness of the method.
Regionale und jährliche Variabilität des Ethanolgebundenen Deuteriumgehaltes italienischer Weine
Zusammenfassung Die SNIF-NMR2H-Analytik wird derzeit als Referenzmethode zur Bestimmung der Herkunft des Ethanols bei Produkten aus Weintrauben erfolgreich angewandt. Die Methode wird auch zur Ermittlung der geographischen Herkunft von Wein eingesetzt. Ziel der vorliegenden Arbeit war es, die Brauchbarkeit dieser Analysenmethode zur Bestimmung des geographischen Ursprungs italienischer Weine zu überprüfen. Dazu wurden Analysenergebnisse von 3309 Weinen aus allen 20 Weinbaugebieten Italiens im Rahmen einer Datenbank des D/H-Verhältnisses gesammelt. Während für die D/HI-Werte eine deutliche Abhängigkeit von der geographischen Breite bestätigt werden konnte, zeigten die D/HII-Werte keinen derartigen Zusammenhang. Auch der Parameter R erbrachte keine weiteren Informationen. Die Häufigkeits-Verteilung der NMR-Werte folgt deutlich einem Nord-Süd-Gradienten, aber sie sind nicht in jeder Region so unterschiedlich, daß eine signifikante Differenzierung möglich ist. Dies resultiert aus den jahrgangs- und gebietsabhängigen Schwankungen. Die SNIF-NMR Methode ist zur Aufklärung bestimmter Verfälschungen (Zuckerzusatz) gut geeignet, bei italienischen Weinen ist jedoch mit dieser Methode das Problem der Bestimmung der geographischen Herkunft nicht lösbar. Durch Messung weiterer stabiler Isotopen sowie durch eine Verbesserung der Probennahme kann eine Erhöhung der Effizienz zum Nachweis der geographischen Herkunft erzielt werden.相似文献