1,721,497 research outputs found
Endemic freshwater planarians of Sardinia: Redescription of Dugesia hepta (Platyhelminthes, Tricladida) with a comparison of the Mediterranean species of the genus
No full textStocchino, G. A., Corso, G., Manconi, R., Casu, S., Pala, M. (2005): Endemic freshwater planarians of Sardinia: Redescription of Dugesia hepta (Platyhelminthes, Tricladida) with a comparison of the Mediterranean species of the genus. Journal of Natural History 39 (22): 1947-1960, DOI: 10.1080/00222930500060025, URL: http://dx.doi.org/10.1080/0022293050006002
Dall'esperienza corsa utili suggerimenti per la diffusione dell'avocado (P. americana Mill.) in Sardegna
No full text
Exploiting Hetero-Junctions to Improve the Performance of III-V Nanowire Tunnel-FETs
No full textThis paper presents full-quantum 3-D simulations predicting the electrical performance of nanowire tunnel-FETs based on III-V hetero-junctions. Our calculations exploit an eight-band k.p Hamiltonian within the nonequilibrium Green's functions formalism and include phonon scattering. It is shown that the on-current of GaSb/InAs hetero-junction tunnel-FETs is limited by quantum confinement effects on the bandstructure induced by the small nanowire diameter necessary to preserve an optimal electrostatic integrity at short gate lengths. To circumvent this problem, additional on-current improvements with no substantial subthreshold swing degradation can be achieved by engineering the source region through the insertion of an InAs/GaSb/InAs quantum well along the transport direction. Such a design option is predicted to provide on/off-current ratios larger than 10(7) even at V-DD = 300 mV
Frontiers, Borders, Limits. Presentation
No full textParlare oggi di letteratura e geografia, cartografia, topografia significa affrontare, chiarire, ricostruire le ideologie e i discorsi iscritti nello spazio; sollecitare la geografia - e i discorsi ad essa correlati - implica perciò l’attivazione di un certo numero di concetti come sapere, potere, scienza, formazioni discorsive, sguardo, episteme. Ognuno di questi termini sarebbe privo di significato – di un significato che in tal modo si qualifica come storico - senza una contestualizzazione geografica
Impact of the gate and insulator geometrical model on the static performance and variability of ultrascaled silicon nanowire FETs
No full textWe investigate the effect of the geometrical model adopted for the gate electrode and for the insulator enveloping the access regions on the full-quantum simulation of ultrascaled nanowire FETs (NW-FETs). We compare the results obtained in the 'minimal' geometry commonly used in simulations with those obtained in a more realistic one, able to fully account for the gate fringing effects. We evaluate the impact of the model geometry on the static performance of NW-FETs and discuss the interplay with the surface roughness and the random distribution of dopants. We find that the I-scriptscriptstyle ON I-scriptscriptstyle OFF ratio evaluated in the minimal geometry can be remarkably underestimated in short devices, notably in the case of small length-To-width ratio. The roughness-induced current degradation and the sensitivity to the surface roughness variability can also suffer from nonnegligible underestimations when evaluated in this geometry. Finally, we point out that an inaccurate description of the device electrostatics is expected to result in an overestimation of the sensitivity to the doping-induced variabilit
A parametric study for distortional buckling stress on cold-formed steel using a neural network
No full textThe process of prediction of distortional buckling stress of cold-formed steel members is often cumbersome and it is also difficult to perform parametric studies in this field to investigate the effect of geometric parameters on Elastic Distortional Buckling Stress (EDBS). To overcome this difficulty a neural network based model and formulation which was presented in a companion paper by the author [Pala M. A new formulation for distortional buckling stress in cold formed steel members. Journal of Constructional Steel Research 2006;62:716-22] is proposed as an alternative approach to investigate the effect of geometric parameters on distortional buckling stress. The model considers the effect of web height, flange width, angle of lip, lip length and flange thickness. The results of the Neural Network model are quite satisfactory and are consistent with the literature. (c) 2006 Elsevier Ltd. All rights reserved
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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