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排序方式: 共有1416条查询结果,搜索用时 15 毫秒
191.
Minds and Machines - In this commentary, we discuss the nature of reversible and irreversible questions, that is, questions that may enable one to identify the nature of the source of their... 相似文献
192.
Luigi Acampora Gaetano Continillo Francesco Saverio Marra Francesco Miccio Massimo Urciuolo 《国际能源研究杂志》2020,44(15):12559-12571
A system consisting of a last-generation Stirling engine (SE) and a fuel burner for distributed power generation has been developed and experimentally investigated. The heat generated by the combustion of two liquid fuels, a standard Diesel fuel and a rapeseed oil, is used as a heat source for the SE, that converts part of the thermal energy into mechanical and then electric energy. The hot head of the SE is kept in direct contact with the flame generated by the burner. The burner operating parameters, designed for Diesel fuel, were changed to make it possible to burn vegetable oils, not suitable for internal combustion engines. The possibility of adopting different configurations of the combustion chamber was taken into account to increase the system efficiency. The preliminary configurations adopted allowed to operate this integrated system, obtaining an electric power up to 4.4 kWel with a net efficiency of 11.6%. 相似文献
193.
Marco Baldi Franco Chiaraluce Nicola Maturo Giacomo Ricciutelli Alessandro Ardito Francesco Barbaglio Stefano Finocchiaro Lorenzo Simone Ricard Abell Javier De Vicente Mattia Mercolino 《International Journal of Satellite Communications and Networking》2019,37(6):571-587
A thorough analysis of the behavior of error‐correcting codes over space links affected by solar scintillation is presented. The relevant channel parameters are fixed through the development of a model based on real missions' data. Both telecommand and telemetry links are considered in fast and slow fading conditions. Besides classical coherent modulation schemes, the possibility to use noncoherent modulation schemes is considered, to eliminate the problem of phase tracking. For the case of channels with very slow fading, the use of external interleavers or erasure coding is proposed to cope with error bursts. 相似文献
194.
Massimo Cimmino 《Journal of Building Performance Simulation》2018,11(4):414-432
A model for the simulation of geothermal systems with parallel- and series-connected boreholes is presented. Mass and heat balance problems are formulated for each component in the system and are assembled into system-level problems. A third problem is formulated to account for heat transfer in the bore field, using the finite line source solution. This third problem is coupled to the system-level heat balance problem by an analytical solution of the heat transfer inside boreholes with multiple U-tubes. The simulation model allows for any number of independent fluid loops within the bore field or within individual boreholes and allows for combinations of specified inlet fluid temperatures and heat extraction rates in independent fluid loops. The model accounts for the axial variation of the fluid and borehole wall temperatures and heat extraction rates. The capabilities of the model are demonstrated through three example simulations. 相似文献
195.
We present and evaluate a classification method to estimate tourist presence in an area from cellular network data. Our approach is based on setting up a classifier to label users according to five main classes: residents, commuters, people in-transit, tourists and excursionists. We experiment the approach in some important tourist cities in Italy: Venice, Florence, Turin and Lecce. In the lack of sound groundtruth data, we analysed the composition of different classes obtaining results in line with domain knowledge. Moreover, these results are also supported by an analysis of the locations frequented by the tourists that well conforms with expectations. Finally, the number of users classified as tourists is strongly correlated with official statistics on tourist presence in the area. 相似文献
196.
Shehata Mohamed Musumeci Francesco Tornatore Massimo 《Photonic Network Communications》2019,37(3):388-398
Photonic Network Communications - The huge data demand envisioned for the 5G requires radical changes in the mobile network architecture and technology. Centralized radio access network (C-RAN) is... 相似文献
197.
Scientometrics - Citation impact is commonly assessed using direct, first-order citation relations. We consider here instead the indirect influence of publications on new publications via... 相似文献
198.
Shubhra S. Pasayat Cory Lund Yusuke Tsukada Massimo Catalano Luhua Wang Moon J. Kim Shuji Nakamura Stacia Keller Umesh K. Mishra 《Journal of Electronic Materials》2020,49(6):3450-3454
Smooth 200 nm thick N-polar InGaN films were grown by metal–organic chemical vapor deposition (MOCVD) on sapphire using a digital approach consisting of a constant In, Ga, and N precursor flow with pulsed injection of H2 into the N2 carrier gas. Using this growth scheme, the H2 injection time was altered and the effect on the morphology and indium incorporation in the films observed. The effect of periodic insertion of additional GaN inter-layers on the surface morphology of the InGaN layers was also studied. 相似文献
199.
Paolo Massimo Buscema Giulia Massini Marco Fabrizi Marco Breda Francesca Della Torre 《Computational Intelligence》2018,34(1):310-344
This research has 6 fundamental aims: (i) to present a modified version of Taylor's interpolation, one that is more effective and faster than the original; (ii) outline the capability of artificial neural networks (ANNs) to perform an optimal functional approximation of the digital elevation model reconstruction from a satellite map, using a small and independent sample of Global Positioning System observations; (iii) demonstrate experimentally how ANNs outperform the traditional and most used algorithm for the height interpolation (Taylor's interpolation); (iv) introduce a new ANN, the Conic Net, able to outperform the results of the classic and more known multilayer perceptron; (v) determine that Conic Nets, even when using Taylor's modified interpolation as input features, are able to optimally approximate the heights with one order of magnitude more than the original satellite map; and (vi) make evident the possibility to interpolate the DEM heights through an ANN, which learns a data set of known points. 相似文献
200.
Massimo Frittelli Anotida Madzvamuse Ivonne Sgura Chandrasekhar Venkataraman 《Journal of scientific computing》2018,77(2):971-1000
We propose and analyse a finite element method with mass lumping (LESFEM) for the numerical approximation of reaction–diffusion systems (RDSs) on surfaces in \({\mathbb {R}}^3\) that evolve under a given velocity field. A fully-discrete method based on the implicit–explicit (IMEX) Euler time-discretisation is formulated and dilation rates which act as indicators of the surface evolution are introduced. Under the assumption that the mesh preserves the Delaunay regularity under evolution, we prove a sufficient condition, that depends on the dilation rates, for the existence of invariant regions (i) at the spatially discrete level with no restriction on the mesh size and (ii) at the fully-discrete level under a timestep restriction that depends on the kinetics, only. In the specific case of the linear heat equation, we prove a semi- and a fully-discrete maximum principle. For the well-known activator-depleted and Thomas reaction–diffusion models we prove the existence of a family of rectangles in the phase space that are invariant only under specific growth laws. Two numerical examples are provided to computationally demonstrate (i) the discrete maximum principle and optimal convergence for the heat equation on a linearly growing sphere and (ii) the existence of an invariant region for the LESFEM–IMEX Euler discretisation of a RDS on a logistically growing surface. 相似文献