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101.
Massimo Negrotti 《AI & Society》2013,28(1):65-73
Usually, the shape of the future is seen as the result of a cultural flow that, according to some privileged cultural variable, like technology, goes undisturbed towards its own outcome. This is a quite naive attitude that has been very rarely successful. Both conventional technology and technology of the artificial show that, within culture, ‘demons’ are always active trying to exploit or even bypass standards in order to give birth to unexpected novelties. This is true within the pure technology area and even more in its artistic extensions. Therefore, no deterministic process is going on but, rather, a permanent remixing of chances that makes any prophecy impossible. 相似文献
102.
Massimo Ghioni Andrea Giudice Sergio Cova Franco Zappa 《Journal of Modern Optics》2013,60(14):2251-2269
Abstract Experimental results obtained with silicon single photon avalanche diodes (SPADs) in quantum key distribution (QKD) at short wavelengths reveal remarkable potential for application in local area networks (LAN) and for free-space transmission at high rate. Actual application prospects, however, depend on the performance level and on the suitability of practical systems using the available silicon SPAD devices. They can be essentially divided in two groups: planar p-n junction structures with a thin depletion layer (typically 1 μm); and reach-through structures with a thick depletion layer (from 20 μm to 150μm). The physical mechanisms that control the device behaviour were investigated and the effect on the key parameters of the detector (quantum detection efficiency, dark counting rate, afterpulsing probability and photon-timing jitter) were thoroughly assessed. A quantitative analysis was made of the influence of such parameters on the quantum bit error rate (QBER). Actual parameters were measured and the attainable performance and system suitability of the two device types evaluated. Comparable performance is obtained, but from a system viewpoint thin SPADs appear inherently better suited to high-rate QKD applications, because of their faster response time, ruggedness, low voltage, low power dissipation and fabrication technology, which is simple, efficient, economical and compatible with monolithic integration of detector and associated circuits. 相似文献
103.
Adnan Ghribi Andrea Tartari Eric Bréelle Jean-Christophe Hamilton Silvia Galli Massimo Gervasi Michel Piat Sebastiano Spinelli Mario Zannoni 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(1):88-99
In order to study an original detection architecture for future cosmology experiments based on wide band adding interferometry,
we have tested a single baseline bench instrument based on commercial components. The instrument has been characterized in
the laboratory with a wide band power detection setup. A method which allows us to reconstruct the complete transfer function
of the interferometer has been developed and validated with measurements. This scheme is useful to propagate the spurious
effects of each component till the output of the detector. 相似文献
104.
Cristian Grossmann Christian Langel Marco Mazzotti Massimo Morbidelli Manfred Morari 《Journal of Process Control》2010,20(4):490-505
This paper presents an optimizing control scheme for simulated moving beds (SMB) that enables to incorporate multi-rate (MR) sampled measurements into the control and estimation problem in a clear and transparent manner. This is particularly relevant for chiral separations where online monitoring requires the combination of various analytical techniques that may operate on widely varying time scales. An MR periodic linear time-varying (PLTV) model is derived for the SMB process. The cyclic nature of the process is exploited by formulating the MR-PLTV model within a repetitive model predictive control framework. Simulation results for the chiral separation of the guaifenesin enantiomers are presented. The proposed multi-rate controller is able to deliver increased productivity while respecting the process and product specifications. 相似文献
105.
Sueva Cantalupo Vito Alessandro Lasorsa Roberta Russo Immacolata Andolfo Giuseppe DAlterio Barbara Eleni Rosato Giulia Frisso Pasquale Abete Gian Marco Cassese Giuseppe Servillo Ivan Gentile Carmelo Piscopo Matteo Della Monica Giuseppe Fiorentino Giuseppe Russo Pellegrino Cerino Carlo Buonerba Biancamaria Pierri Massimo Zollo Achille Iolascon Mario Capasso 《International journal of molecular sciences》2021,22(10)
Genome-wide association studies (GWAS) found locus 3p21.31 associated with severe COVID-19. CCR5 resides at the same locus and, given its known biological role in other infection diseases, we investigated if common noncoding and rare coding variants, affecting CCR5, can predispose to severe COVID-19. We combined single nucleotide polymorphisms (SNPs) that met the suggestive significance level (P ≤ 1 × 10−5) at the 3p21.31 locus in public GWAS datasets (6406 COVID-19 hospitalized patients and 902,088 controls) with gene expression data from 208 lung tissues, Hi-C, and Chip-seq data. Through whole exome sequencing (WES), we explored rare coding variants in 147 severe COVID-19 patients. We identified three SNPs (rs9845542, rs12639314, and rs35951367) associated with severe COVID-19 whose risk alleles correlated with low CCR5 expression in lung tissues. The rs35951367 resided in a CTFC binding site that interacts with CCR5 gene in lung tissues and was confirmed to be associated with severe COVID-19 in two independent datasets. We also identified a rare coding variant (rs34418657) associated with the risk of developing severe COVID-19. Our results suggest a biological role of CCR5 in the progression of COVID-19 as common and rare genetic variants can increase the risk of developing severe COVID-19 by affecting the functions of CCR5. 相似文献
106.
Polymorphic Torus is a novel interconnection network for SIMD massively parallel computers, able to support effectively both local and global communication. Thanks to this characteristic, Polymorphic Torus is highly suitable for computer vision applications, since vision involves local communication at the low-level stage and global communication at the intermediate- and high-level stages. In this paper we evaluate the performance of Polymorphic Torus in the computer vision domain. We consider a set of basic vision tasks, namely,convolution, histogramming, connected component labeling, Hough transform, extreme point identification, diameter computation, andvisibility, and show how they can take advantage of the Polymorphic Torus communication capabilities. For each basic vision task we propose a Polymorphic Torus parallel algorithm, give its computational complexity, and compare such a complexity with the complexity of the same task inmesh, tree, pyramid, and hypercube interconnection networks. In spite of the fact that Polymorphic Torus has the same wiring complexity as mesh, the comparison shows that in all of the vision tasks under examination it achieves complexity lower than or at most equal to hypercube, which is the most powerful among the interconnection networks considered. 相似文献
107.
In certain regions of operating conditions, chemical reactors may exhibit parametric sensitivity; i.e., small changes in one
or more of the reactor input parameters lead to much larger changes in the output variables. Since such behaviour leads to
deleterious performance, it is of practical interest to identify regions of parametric sensitivity in the reactor parameter
space. Until recently, this could be done only to describe thermal runaway, and only for those systems where a temperature
profile could be defined. Both of these limitations can be removed by consideringthe generalized criterion for parametric sensitivity, whereby sensitivity ofany output of the model toany input can be treated. Applications of the generalized criterion are discussed, with specific examples including pseudohomogeneous
and heterogeneous model tubular reactors, a nonisothermal CSTR, and a polymerization reactor.
Dedicated to Dr L K Doraiswamy — Gentleman, Scholar, Friend — on his sixtieth birthday. 相似文献
108.
Maria Silvia Tonti Marco Masseti Giovanna Poli Massimo Paci Pierluigi Magagnini Claudia Forte Carlo Alberto Veracini 《Polymer Engineering and Science》1998,38(9):1491-1505
The transesterification of poly(ethylene terephthalate) (PET) with a mixture of sebacic acid (S), 4,4′-diacetoxybiphenyl (B) and 4-acetoxybenzoic acid (H), carried out under conditions expectedly favoring the formation of a p(ET-SBH) random copolyester, produces biphasic materials with an isotropic matrix and a highly fibrous, liquid-crystalline dispersed phase. Spectroscopic, calorimetric, microscopic and diffractometric characterization of the fractions separated by solvent extraction has shown that the two phases consist of practically random copolyesters having different average composition. Interestingly, the degree of aromaticity of the matrix is even lower than that of PET, whereas that of the minor phase is appreciably higher than that calculated for the SBH copolyester that would be produced from the monomer mixture in the absence of PET. This unexpected result is interpreted on the basis of an enthalpy-driven progressive diffusion of aromatic-rich material toward the mesophase which segregates at an early stage of the polycondensation within the isotropic mixture of low molar mass oligomers initially produced by the PET acidolysis. Thus, an increasing differentiation, rather than an equilibration, of the composition of the two phases takes place. It is noteworthy that, despite the strong compositional difference, the two phases of these products show fairly good compatibility and interfacial adhesion. 相似文献
109.
A comparison of bibliometric indicators for computer science scholars and journals on Web of Science and Google Scholar 总被引:1,自引:0,他引:1
Massimo Franceschet 《Scientometrics》2010,83(1):243-258
Given the current availability of different bibliometric indicators and of production and citation data sources, the following two questions immediately arise: do the indicators’ scores differ when computed on different data sources? More importantly, do the indicator-based rankings significantly change when computed on different data sources? We provide a case study for computer science scholars and journals evaluated on Web of Science and Google Scholar databases. The study concludes that Google scholar computes significantly higher indicators’ scores than Web of Science. Nevertheless, citation-based rankings of both scholars and journals do not significantly change when compiled on the two data sources, while rankings based on the h index show a moderate degree of variation. 相似文献
110.
Marco Brucale Dr. Massimo Sandal Dr. Selena Di Maio Aldo Rampioni Dr. Isabella Tessari Dr. Laura Tosatto Marco Bisaglia Dr. Luigi Bubacco Prof. Bruno Samorì Prof. 《Chembiochem : a European journal of chemical biology》2009,10(1):176-183
α‐synuclein (α‐Syn) is an abundant brain protein whose mutations have been linked to early‐onset Parkinson's disease (PD). We recently demonstrated, by means of a single‐molecule force spectroscopy (SMFS) methodology, that the conformational equilibrium of monomeric wild‐type (WT) α‐Syn shifts toward β‐containing structures in several unrelated conditions linked to PD pathogenicity. Herein, we follow the same methodology previously employed for WT α‐Syn to characterize the conformational heterogeneity of pathological α‐Syn mutants A30P, A53T, and E46K. Contrary to the bulk ensemble‐averaged spectroscopies so far employed to this end by different authors, our single‐molecule methodology monitored marked differences in the conformational behaviors of the mutants with respect to the WT sequence. We found that all the mutants have a much higher propensity than the WT to adopt a monomeric compact conformation that is compatible with the acquiring of β structure. Mutants A30P and A53T show a similar conformational equilibrium that is significantly different from that of E46K. Another class of conformations, stabilized by mechanically weak interactions (MWI), shows a higher variety in the mutants than in the WT protein. In the A30P mutant these interactions are relatively stronger, and therefore the corresponding conformations are possibly more structured. The more structured and globular conformations of the mutants can explain their higher propensity to aggregate with respect to the WT. 相似文献