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排序方式: 共有350条查询结果,搜索用时 31 毫秒
341.
Ioannis K. Brilakis Lucio Soibelman Yoshihisa Shinagawa 《Advanced Engineering Informatics》2006,20(4):443-452
The capability to automatically identify shapes, objects and materials from the image content through direct and indirect methodologies has enabled the development of several civil engineering related applications that assist in the design, construction and maintenance of construction projects. This capability is a product of the technological breakthroughs in the area of image processing that has allowed for the development of a large number of digital imaging applications in all industries. In this paper, an automated and content based construction site image retrieval method is presented. This method is based on image retrieval techniques, and specifically those related with material and object identification and matches known material samples with material clusters within the image content. The results demonstrate the suitability of this method for construction site image retrieval purposes and reveal the capability of existing image processing technologies to accurately identify a wealth of materials from construction site images. 相似文献
342.
In this contribution we show how it is possible to construct a new multilayer dielectric ground plane using bianisotropic
media that is highly reflective over a broad range of wavelengths at all angles. This omnidirectional dielectric reflector-unlike
metal-is nearly totally lossless and can be engineered to have extremely high reflectivity. The plane wave solution is then
used to study in a rigorous way the wave equations satisfied by the electromagnetic field in a layered structure filled with
such a material. Numerical results are also presented as a function of the material parameters in order to demonstrate the
features of this approach. 相似文献
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Angelo Bozzola Marco Liscidini Lucio Claudio Andreani 《Progress in Photovoltaics: Research and Applications》2014,22(12):1237-1245
We theoretically investigate light trapping with disordered 1D photonic structures in thin‐film crystalline silicon solar cells. The disorder is modelled in a finite‐size supercell, which allows the use of rigorous coupled‐wave analysis to calculate the optical properties of the devices and the short‐circuit current density Jsc. The role of the Fourier transform of the photonic pattern in the light trapping is investigated, and the optimal correlation between size and position disorder is found. This result is used to optimize the disorder in a more effective way, using a single parameter. We find that a Gaussian disorder always enhances the device performance with respect to the best ordered configuration. To properly quantify this improvement, we calculate the Lambertian limit to the absorption enhancement for 1D photonic structures in crystalline silicon, following the previous work for the 2D case [M.A. Green, Progr. Photovolt: Res. Appl. 2002; 10 (4), pp. 235–241]. We find that disorder optimization can give a relevant contribution to approach this limit. Finally, we propose an optimal disordered 2D configuration and estimate the maximum short‐circuit current that can be achieved, potentially leading to efficiencies that are comparable with the values of other thin‐film solar cell technologies. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
346.
Probing small network differences in sulfur‐cured rubber compounds by combining nuclear magnetic resonance and swelling methods 下载免费PDF全文
Murali Krishna Dibbanti Michele Mauri Lucio Mauri Gabriele Medaglia Roberto Simonutti 《应用聚合物科学杂志》2015,132(43)
We studied the network structure of elastomers based on polyisoprene, polybutadiene, and their blends in the narrow range of formulations compatible with actual use in the automotive tyre industry. Cross‐link density (CLD) was quantified comparatively by low‐field 1H multiple quantum time domain nuclear magnetic resonance (MQ TD‐NMR) and by equilibrium swelling technique. The robustness and agreement of the two methods was demonstrated in measuring minute alterations of unfilled vulcanizates beyond the optimum cure time. Comparison with samples where polysulfidic bonds were selectively cleaved also demonstrates that the length of the sulfur chain constituting the cross‐link does not significantly affect residual dipolar coupling. Kraus, Lorenz, and Parks correction for filler restriction on swelling is validated by MQ TD‐NMR, which also allows extracting information on cross‐link distribution not provided by swelling measurement. Cross‐link distributions in the blends were demonstrated to be significantly different from the weighted average of the pure samples, while average proton–proton residual dipolar coupling values correspond. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42700. 相似文献
347.
Potential effectiveness of visible and near infrared spectroscopy coupled with wavelength selection for real time grapevine leaf water status measurement 下载免费PDF全文
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Behaviormetrika - The present study explored the potential of a new neurocognitive approach to test equity which integrates evidence from eye-tracking and functional near-infrared spectroscopy with... 相似文献
350.
Franca Rossi Ilaria Del Matto Paola Manocchio Maria Antonietta Saletti Luciano Ricchiuti Lucio Marino 《International Journal of Dairy Technology》2023,76(3):572-582
The aim of this study was to investigate the survival of Campylobacter jejuni in dairy matrices by viability qPCR. Survival in UHT milk was examined first and the cheese outbreak strain, C. jejuni 11 218 showed enhanced tendency to become viable but nonculturable (VBNC). It survived for long at different pH values, in raw and fermented milk and cheese. Viability qPCR was also used to examine the occurrence of viable Campylobacter spp. in raw milk, detecting the bacteria in 40.9% of 25 mL samples negative on culture. Results showed that viability qPCR is valuable in estimating Campylobacter risk in dairy products. 相似文献