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141.
142.
Nikolaos Gavanas Efthimios Moutsiakis Anastasia Tasopoulou Eleni Verani Vasilios Fourkas 《影响评估与项目评价》2018,36(4):294-307
Territorial Impact Assessment (TIA) is proposed as a critical tool in order to investigate the way policies affect spatial development and hence territorial cohesion. The paper introduces a TIA methodological model in relation to transport sector. The design of the methodological model is based on a quantitative evaluation framework that comprises a set of selected indicators applied in a cross-border area of southeast Europe, influenced by the operation of the Greek motorway system of Egnatia and its vertical axes. The indicators are grouped into three main fields of TIA, i.e. transport intermodality, polycentric spatial organization and cross-border territorial cooperation. The TIA’s indicators are approximated by quantitative analysis. The procedure concludes to an overall composite indicator measuring the ‘level of territorial cohesion’ along with some core results and the expected added value. It also highlights some key technical aspects about the routines used and proceeds to suggestions for further refinement. 相似文献
143.
Kai Sun Wei Xiao Sheng Ye Nikolaos Kalfagiannis Kian Shen Kiang C. H. de Groot Otto L. Muskens 《Advanced materials (Deerfield Beach, Fla.)》2020,32(25):2001534
New methods for achieving high-quality conducting oxide metasurfaces are of great importance for a range of emerging applications from infrared thermal control coatings to epsilon-near-zero nonlinear optics. This work demonstrates the viability of plasma patterning as a technique to selectively and locally modulate the carrier density in planar Al-doped ZnO (AZO) metasurfaces without any associated topographical surface profile. This technique stands in strong contrast to conventional physical patterning which results in nonplanar textured surfaces. The approach can open up a new route to form novel photonic devices with planar metasurfaces, for example, antireflective coatings and multi-layer devices. To demonstrate the performance of the carrier-modulated AZO metasurfaces, two types of devices are realized using the demonstrated plasma patterning. A metasurface optical solar reflector is shown to produce infrared emissivity equivalent to a conventional etched design. Second, a multiband metasurface is achieved by integrating a Au visible-range metasurface on top of the planar AZO infrared metasurface. Independent control of spectral bands without significant cross-talk between infrared and visible functionalities is achieved. Local carrier tuning of conducting oxide films offers a conceptually new approach for oxide-based photonics and nanoelectronics and opens up new routes for integrated planar metasurfaces in optical technology. 相似文献
144.
145.
Software and Systems Modeling - Statecharts constitute an executable language for modelling event-based reactive systems. The essential complexity of statechart models solicits the need for... 相似文献
146.
Shengfu Yang Cheng Feng Daniel Spence Aula M. A. A. Al Hindawi Elspeth Latimer Andrew M. Ellis Chris Binns Davide Peddis Sarnjeet S. Dhesi Liying Zhang Yafei Zhang Kalliopi N. Trohidou Marianna Vasilakaki Nikolaos Ntallis Ian MacLaren Frank M. F. de Groot 《Advanced materials (Deerfield Beach, Fla.)》2017,29(1)
147.
Nikolaos Moustakis Shuai Yuan Simone Baldi 《International Journal of Adaptive Control and Signal Processing》2018,32(5):665-680
This paper addresses the problem of asymptotic tracking for switched linear systems with parametric uncertainties and dwell‐time switching, when input measurements are quantized due to the presence of a communication network closing the control loop. The problem is solved via a dynamic quantizer with dynamic offset that, embedded in a model reference adaptive control framework, allows the design of the adaptive adjustments for the control parameters and for the dynamic range and dynamic offset of the quantizer. The overall design is carried out via a Lyapunov‐based zooming procedure, whose main feature is overcoming the need for zooming out at every switching instant, in order to compensate for the possible increment of the Lyapunov function at the switching instants. It is proven analytically that the resulting adjustments guarantee asymptotic state tracking. The proposed quantized adaptive control is applied to the piecewise linear model of the NASA Generic Transport Model aircraft linearized at multiple operating points. 相似文献
148.
Stasinakis AS Thomaidis NS Mamais D Papanikolaou EC Tsakon A Lekkas TD 《Water research》2003,37(9):2140-2148
The effect of hexavalent chromium, Cr(VI), addition on various operating parameters of activated sludge process was evaluated. To accomplish this, two parallel lab-scale continuous-flow activated sludge plants were operated. One was used as a control plant, while the other received Cr(VI) concentrations equal to 0.5, 1, 3 and 5 mgl(-1). Cr(VI) concentrations of 0.5 mgl(-1) caused significant inhibition of the nitrification process (up to 74% decrease in ammonia removal efficiency). On the contrary, the effect of Cr(VI) on organic substrate removal was minor for concentrations up to 5 mgl(-1), indicating that heterotrophic microorganisms are less sensitive to Cr(VI) than nitrifiers. Activated sludge floc size and structure characterization showed that Cr(VI) concentrations higher than 1 mgl(-1) reduced the filaments abundance, causing the appearance of pin-point flocs and free-dispersed bacteria. Additionally, the variability of protozoa and rotifers was reduced. As a result of disperse growth, effluent quality deteriorated, since significant amounts of suspended solids escaped with the effluent. Termination of Cr(VI) addition led to a partial recovery of the nitrification process (up to 57% recovery). Similar recovery signs were not observed for activated sludge floc size and structure. Finally, shock loading to the control plant with 5 mgl(-1) Cr(VI) for 2 days resulted in a significant inhibition of the nitrification process and a reduction in filamentous microorganisms abundance. 相似文献
149.
Molecular simulation studies of adsorption of hydrogen cyanide and methyl ethyl ketone on zeolite NaX and activated carbon 总被引:1,自引:0,他引:1
In the present research study the primary aim is to understand and characterize the physical adsorption of polar molecules namely, hydrogen cyanide and methyl ethyl ketone (MEK) in zeolite NaX, and activated carbon through detailed Monte-Carlo simulations and computational quantum chemistry techniques. The sorption capacity and affinity of the zeolite is compared with activated carbon with different acid site concentrations, type of acid site, and pore sizes by simulating single component isotherms and Henry's constant at 25 degrees C. The role/contribution of certain types of electrostatic interactions namely charge-dipole, charge-induced dipole with zeolite NaX and activated carbon, as well as dipole-dipole interactions among polar molecules is analyzed and discussed. 相似文献
150.
The resonant properties of a closed and symmetric cyclic array of N coupled microring resonators (coupled-microring resonator regular N-gon) are for the first time determined analytically by applying the transfer matrix approach and Floquet theorem for periodic propagation in cylindrically symmetric structures. By solving the corresponding eigenvalue problem with the field amplitudes in the rings as eigenvectors, it is shown that, for even or odd N, this photonic molecule possesses 1 + N/2 or 1+N resonant frequencies, respectively. The condition for resonances is found to be identical to the familiar dispersion equation of the infinite coupled-microring resonator waveguide with a discrete wave vector. This result reveals the so far latent connection between the two optical structures and is based on the fact that, for a regular polygon, the field transfer matrix over two successive rings is independent of the polygon vertex angle. The properties of the resonant modes are discussed in detail using the illustration of Brillouin band diagrams. Finally, the practical application of a channel-dropping filter based on polygons with an even number of rings is also analyzed. 相似文献