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151.
Acoustic Green's function allows the analysis of localisation of acoustic modes and of their possible confinement. Electromagnetic Green's function allows a consistent analysis of both scattering mechanisms (elasto-optic and ripple) and their interference. The computed cross-section is directly comparable with experimental spectra. 相似文献
152.
Subset ARMA Model Identification Using Genetic Algorithms 总被引:1,自引:0,他引:1
Carlo Gaetan 《时间序列分析杂志》2000,21(5):559-570
Subset models are often useful in the analysis of stationary time series. Although subset autoregressive models have received a lot of attention, the same attention has not been given to subset autoregressive moving-average (ARMA) models, as their identification can be computationally cumbersome. In this paper we propose to overcome this disadvantage by employing a genetic algorithm. After encoding each ARMA model as a binary string, the iterative algorithm attempts to mimic the natural evolution of the population of such strings by allowing strings to reproduce, creating new models that compete for survival in the next population. The success of the proposed procedure is illustrated by showing its efficiency in identifying the true model for simulated data. An application to real data is also considered. 相似文献
153.
Small size photovoltaic modules can harvest enough energy to power many personal devices and wireless sensor nodes. The prediction of solar energy intake is possible thanks to the periodical availability of the sunlight and its cyclic behavior. Thus, smart and innovative power management strategies can take advantage from intake prediction algorithms to optimize the energy usage by keeping the system in low power state as long as possible. On the other hand, very accurate predictions need time and energy because of complex calculations, thus an algorithm that can provide the optimal trade-off between computational effort and accuracy is a breakthrough for systems with tight power constraints. In this paper we introduce an innovative, efficient and reliable solar prediction algorithm, the weather conditioned moving average (WCMA). The algorithm has been further enhanced to increase performance using a phase displacement regulator (PDR) which reduces the average error to less than 9.2% at a minimum energy cost. The proposed new algorithm compares favorably with several competing approaches. 相似文献
154.
Reviews the book, Psychoanalysis at the margins by Paul E. Stepansky (see record 2009-22624-000). For more than two decades, there have been conferences and publications about psychoanalysis’ being in a crisis. None of these calls has led to a radical reorganization or reorientation of psychoanalysis. The result has been that psychoanalysis has become marginal: if in the 1960s a large percentage of professorships in psychiatry were held by psychoanalysts, now there are practically none. There are hardly any graduate programs in clinical psychology that are psychoanalytically oriented, and there are very few professorships in psychology that are in the hands of psychoanalysts. And while there are still many psychoanalytic institutes that succeed in attracting candidates, there are almost no patients left that come for classical psychoanalysis. Stepansky’s book is a major achievement and should be read by anybody concerned with the future of psychoanalysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
155.
Francesco Ciardelli Osvaldo Pieroni Adriano Fissi Carlo Carlini Angelina Altomare 《Polymer International》1989,21(2):97-106
Photoresponsive macromolecules are of interest both as novel organic materials for applications in photodevices and as models for photomodulated biological processes. The presence in polymer chains of photosensitive groups and of chiral groups capable of inducing optical activity into the polymer is very useful for the analysis of photomodulated structural variations and allows storage of the light effect in the form of chiral information. Polypeptides bearing photochromic groups in the side chains are very convenient as the chiroptical properties of the peptide chromophore can be correlated to the backbone conformation. Thus polymers of L-aspartic acid, L-glutamic acid and L-lysine with azobenzene or stilbene groups attached covalently to the side chains are discussed in terms of photoinduced conformational changes and chiroptical information storage in the spectral region of the peptide and of the photoresponsive chromophore. Optically active photochromic macromolecules with hydrocarbon backbone, such as copolymers of (—)-menthyl acrylate with vinyl or acryloyl derivatives of azobenzene, stilbene and indolinospirobenzopyran, also show in some cases photodependence of chiroptical properties with evidence of at least local conformational changes as a consequence of light irradiation which can be used for chiral information. 相似文献
156.
Carlo Formenti und Aristide Scipiotti 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1906,12(5):283-295
Ohne ZusammenfassungMitteilung aus dem Laboratorio Chimico Municipale in Mailand. 相似文献
157.
Giancarlo Cravotto Stefano Di Carlo Massimo Curini Vander Tumiatti Carlo Roggero 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2007,82(2):205-208
Microwave (MW) and high‐intensity ultrasound (US) provide innovative techniques for the degradation of persistent organic pollutants (POPs). When Fenton's reagent is used to treat industrial wastes, organic pollutants are degraded by highly reactive hydroxyl radicals (HO·) that can oxidize almost any organic compound to carbon dioxide and water. These reactions, when carried out under US or MW, are faster and much more efficient. The present work assesses the combined effect of US and MW using a new flow reactor developed in our laboratory. In this 5 L pilot reactor the liquid was pumped in parallel through a modified domestic MW oven and through a cell where it was irradiated with two US generators working at 20 and 300 kHz, while MW irradiation took place in a modified domestic oven. We studied the degradation of 2,4‐dibromophenol (0.1 g L?1 in water) by Fenton's reagent, assessing the contribution of each energy source to the overall effect, and found that MW and US‐300 kHz played the main role. A modest amount of oxidant (6 mL 30% H2O2 per 1 L of polluted water) sufficed to achieve complete degradation within 6 h, at which time organic compounds were no longer detectable. Even if no Fenton's reagent was added, about one half of the pollutant was degraded after 3 h irradiation. Copyright © 2007 Society of Chemical Industry 相似文献
158.
Francesco Aversano Alberto Ferrario Stefano Boldrini Carlo Fanciulli Marcello Baricco Alberto Castellero 《Journal of Materials Engineering and Performance》2018,27(12):6306-6313
Thermoelectric TiNiSn-based half Heusler compound reveals high Seebeck coefficient and electrical conductivity, leading to high power factor. As a consequence of the solidification path, TiNiSn single phase cannot be obtained directly from the liquid phase. Thus, a long annealing step is needed to homogenize the alloy. In this work, we present a new processing route for half Heusler compound formation, combining arc melting of pure elements, rapid solidification of the molten alloy and sintering. Rapid solidification of the molten alloy allows to obtain almost single TiNiSn phase, limiting the formation of the primary TiNi2Sn phase as a consequence of the deep undercooling of the liquid. The rapidly solidified alloy was ground to powder and sintered by open die pressing. As-sintered samples show a density around 95% of the theoretical value. Thermal cycling of the sintered samples shows evolution of the phases, suggesting that after sintering the sample is not in equilibrium yet. After the second thermal cycle thermoelectric properties become reproducible, indicating the attainment of the equilibrium. In conclusion, the proposed processing route allows to obtain dense TiNiSn in bulk form avoiding the time-consuming annealing step, typically used to homogenize this alloy after solidification. 相似文献
159.
Carlo Marini Anna M. Diaz-Rovira B. J. Kennedy Boby Joseph 《Journal of Materials Engineering and Performance》2018,27(12):6322-6327
The effort to find thermoelectric materials suitable for different applications is an intense research topic of a large material science community. In this context, A-site-deficient La1/3NbO3, which shows an irreversible pressure-induced amorphization at above 15 GPa, has attracted recent attention. Here, we present a temperature-dependent Nb K-edge extended x-ray absorption fine structure (EXAFS) study of La1/3NbO3 in the range 77-500 K probing the Nb-O bond correlations. These results are compared with the Nb-O bond correlations in two related oxides NbO2 and Nb2O5. In comparison with NbO2 and Nb2O5, the Nb-O bond mean square relative displacements in La1/3NbO3 show much weaker temperature dependence revealing its enhanced spring constant. The “A” site deficiency in La1/3NbO3 may allow the oxygen atoms to preserve their local geometry and thus are less responsive to the external stimuli like temperature, which may be important in determining the thermal and electrical conductivity properties of this system. 相似文献
160.
Irene Vanni Simona Coco Anna Truini Marta Rusmini Maria Giovanna Dal Bello Angela Alama Barbara Banelli Marco Mora Erika Rijavec Giulia Barletta Carlo Genova Federica Biello Claudia Maggioni Francesco Grossi 《International journal of molecular sciences》2015,16(12):28765-28782
Next-generation sequencing (NGS) is a cost-effective technology capable of screening several genes simultaneously; however, its application in a clinical context requires an established workflow to acquire reliable sequencing results. Here, we report an optimized NGS workflow analyzing 22 lung cancer-related genes to sequence critical samples such as DNA from formalin-fixed paraffin-embedded (FFPE) blocks and circulating free DNA (cfDNA). Snap frozen and matched FFPE gDNA from 12 non-small cell lung cancer (NSCLC) patients, whose gDNA fragmentation status was previously evaluated using a multiplex PCR-based quality control, were successfully sequenced with Ion Torrent PGM™. The robust bioinformatic pipeline allowed us to correctly call both Single Nucleotide Variants (SNVs) and indels with a detection limit of 5%, achieving 100% specificity and 96% sensitivity. This workflow was also validated in 13 FFPE NSCLC biopsies. Furthermore, a specific protocol for low input gDNA capable of producing good sequencing data with high coverage, high uniformity, and a low error rate was also optimized. In conclusion, we demonstrate the feasibility of obtaining gDNA from FFPE samples suitable for NGS by performing appropriate quality controls. The optimized workflow, capable of screening low input gDNA, highlights NGS as a potential tool in the detection, disease monitoring, and treatment of NSCLC. 相似文献