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51.
Massimiliano Scopelliti Maria Vittoria Giuliani Ferdinando Fornara 《Universal Access in the Information Society》2005,4(2):146-155
The study presented in this paper aims at improving the current understanding of human-robot interaction by adopting a psychological approach. The acceptability of robotic devices in home settings, especially by elderly people, does not depend only on the practical benefits they can provide, but on complex relationships between the cognitive, affective and emotional components of peoples images of robots. This study has investigated the main dimensions of these representations, by comparing the attitudes towards technology in general, and domestic robots in particular, held by people at different stages of the lifespan. The results confirm that age is a critical variable. 相似文献
52.
Ceramic nano-pigments have been recently developed for ink-jet decoration of ceramic tiles using quadrichromic technology (cyan, magenta, yellow, and black colours). The colouring mechanisms and performance of CoAl2O4, Au, (Ti,Cr,Sb)O2 and CoFe2O4 nano-pigments were investigated by DRS, XRD and colorimetry. The nano-pigments were dispersed in several ceramic glazes and glassy coatings and their colour performance was compared with that of conventional micro-pigments. Each nano-pigment was characterized in terms of its colour mechanism and chemico-physical stability. Although the micro-pigments provided more saturated hues, intense colours were achievable in nano-pigments despite their very small particle size (<50 nm). Limitations to the use of nano-pigments arose for very high firing temperatures (>1200 °C) due to particle growth (e.g. Au) or dissolution in the glassy phase (e.g. titania). 相似文献
53.
Fuel resistance is an important characteristic of asphalt binders, especially when used in airport fields and filling stations. However, the relevant standards are presently lacking and the scientific literature on the development of suited formulations is sparse. In this paper, a simple procedure to assess the fuel resistance of asphalts (considered in a dynamic sense) is proposed. A number of polymer modified asphalts (PMAs), prepared from two bases and 4 or 6 wt% of several polymers, have been analyzed with this procedure and the relationships between fuel resistance and morphology of the PMAs, the chemical structure of the polymers and the composition of the asphalt bases have been investigated. 相似文献
54.
Claudio Ferraro Esther Garcia‐Tuñon Victoria G. Rocha Suelen Barg Maria Dolores Fariñas Tomas E. Gomez Alvarez‐Arenas Giorgio Sernicola Finn Giuliani Eduardo Saiz 《Advanced functional materials》2016,26(10):1636-1645
The directional freezing of microfiber suspensions is used to assemble highly porous (porosities ranging between 92% and 98%) SiC networks. These networks exhibit a unique hierarchical architecture in which thin layers with honeycomb‐like structure and internal strut length in the order of 1–10 μm in size are aligned with an interlayer spacing ranging between 15 and 50 μm. The resulting structures exhibit strengths (up to 3 MPa) and stiffness (up to 0.3 GPa) that are higher than aerogels of similar density and comparable to other ceramic microlattices fabricated by vapor deposition. Furthermore, this wet processing technique allows the fabrication of large‐size samples that are stable at high temperature, with acoustic impedance that can be manipulated over one order of magnitude (0.03–0.3 MRayl), electrically conductive and with very low thermal conductivity. The approach can be extended to other ceramic materials and opens new opportunities for the fabrication of ultralight structures with unique mechanical and functional properties in practical dimensions. 相似文献
55.
Claudio Zanotti Alessandra Tacca Marzio Monagheddu Noemi Bertolino Piero Giuliani 《Propellants, Explosives, Pyrotechnics》2004,29(2):112-117
A numerical approach to investigate the heating and the ignition of powder mixtures by radiant energy is presented. The ignition study is based on the possibility of separating the initiation transient from the propagation process, by operating in thermal explosion mode. 相似文献
56.
With a semiclassical model of the optical amplifier, we calculate the evolution of noise along optically amplified lines in presence of nonlinear interaction between signal and amplified spontaneous emission, amplifier saturation, fiber dispersion and vacuum field fluctuations associated with attenuation of the fiber. The noise figure (NF) is calculated for two representative cases of long and short-distance links with different numbers of optical amplifiers and for several fiber dispersions. Results indicate that the optimum number of optical amplifiers is limited by the increase of nonlinear effects with signal power 相似文献
57.
Marzia Pucci Stefania Raimondo Ornella Urzì Marta Moschetti Maria Antonietta Di Bella Alice Conigliaro Nadia Caccamo Marco Pio La Manna Simona Fontana Riccardo Alessandro 《International journal of molecular sciences》2021,22(22)
Tumor-associated macrophages play a key role in promoting tumor progression by exerting an immunosuppressive phenotype associated with the expression of programmed cell death ligand 1 (PD-L1). It is well known that tumor-derived small extracellular vesicles (SEVs) affect the tumor microenvironment, influencing TAM behavior. The present study aimed to examine the effect of SEVs derived from colon cancer and multiple myeloma cells on macrophage functions. Non-polarized macrophages (M0) differentiated from THP-1 cells were co-cultured with SEVs derived from a colorectal cancer (CRC) cell line, SW480, and a multiple myeloma (MM) cell line, MM1.S. The expression of PD-L1, interleukin-6 (IL-6), and other inflammatory cytokines as well as of the underlying molecular mechanisms were evaluated. Our results indicate that SEVs can significantly upregulate the expressions of PD-L1 and IL-6 at both the mRNA and protein levels and can activate the STAT3 signaling pathway. Furthermore, we identified the TLR4/NF-kB pathway as a convergent mechanism for SEV-mediated PD-L1 expression. Overall, these preliminary data suggest that SEVs contribute to the formation of an immunosuppressive microenvironment. 相似文献
58.
The network structure of natural rubber (NR) achieved during vulcanization was analyzed using the model of rubber elasticity based on the tube concept, applied to the treatment of the stress-strain measurements. This theory allows the separation of constraint and crosslink contributions. Also, network parameters can be calculated. The crosslink level of the material was changed using different times and temperatures of cure. The change in the molecular parameters of the model with the degree of cure was estimated. The present research is useful for the precise determination of the chemical crosslink density of the NR network. The values were compared with those obtained by means of equilibrium volume swelling measurement. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1085–1092, 1997 相似文献
59.
Giuseppe Espa Danila Filipponi Diego Giuliani Davide Piacentino 《Papers in Regional Science》2014,93(Z1):S113-S135
In this paper, spatial shift‐share decomposition is analysed when applied to Italian data on regional business change at plant level, over the period 2004–2009. A new type of spatial decomposition, which looks more effectively at neighbourhood influence, is introduced here. Notable results emerge from the empirical investigation. First, it can be seen that the spatial level of aggregation greatly affects results. Second, evidence of neighbourhood advantage in the Southern NUTS 3 regions is found, together with opposite results for the Central‐Northern NUTS 3 regions. Finally, evidence of positive industrial mix effects is only found in Central‐Northern Italy. 相似文献
60.