1,844 research outputs found
Technical change, non-tariff barriers, and the development of the Italian locomotive industry, 1850â1913
The locomotive industry was one of the relatively sophisticated âhigh techâ
sectors in which Italy, a late industrializer, was successful before 1913. Using
technical data on the performance of different vintages of locomotives, we
construct a new industry-level index of technical change. We also study the
impact of different policy instruments (import duties, non-tariff trade barriers,
and other discretionary interventions) in shaping the development of the industry.
Our reassessment reveals not only the sound technological performance of Italian
locomotives and successful industry growth, but also the critical role played by
non-tariff barriers for the development of the industry
Evolving gaps: Occupational structure in southern and northern Italy, 1400â1861
During the Risorgimento (1800â61), southern Italy was less
industrial than central-northern Italy and initially agricultural
provinces in the north saw rapid structural transformation.
During the Renaissance (1400â1600), structural
transformation in the south led to a near halving of the initial
difference in agricultural employment share between
the centre-north and the south, but convergence came to
a halt with the âseventeenth-century crisisâ. These trends
suggest that regional inequality was evolving rather than
persistent
Coordination between leaf and root traits in Mediterranean coastal dune plants
Plant trait-based functional spectra are crucial to assess ecosystem functions and services. Whilst most research has focused on aboveground vegetative traits (leaf economic spectrum, LES), contrasting evidence on any coordination between the LES and root economic spectrum (RES) has been reported. Studying spectra variation along environmental gradients and accounting for species' phylogenetic relatedness may help to elucidate the strength of coordination between above- and belowground trait variation.center dot We focused on leaf and root traits of 39 species sampled in three distinct habitats (front, back and slack) along a shoreline-inland gradient on coastal dunes. We tested, within a phylogenetic comparative framework, for the presence of the LES and RES, for any coordination between these spectra, and explored their relation to variation in ecological strategies along this gradient.center dot In each habitat, three-quarters of trait variation is captured in two-dimensional spectra, with species' phylogenetic relatedness moderately influencing coordination and trade-off between traits. Along the shoreline-inland gradient, aboveground traits support the LES in all habitats. Belowground traits are consistent with the RES in the back-habitat only, where the environmental constraints are weaker, and a coordination between leaf and root traits was also found, supporting the whole-plant spectrum (PES).center dot This study confirms the complexity when seeking any correlation between the LES and RES in ecosystems characterized by multiple environmental pressures, such as those investigated here. Changes in traits adopted to resist environmental constraints are similar among species, independent of their evolutionary relatedness, thus explaining the low phylogenetic contribution in support of our results
Checklist della flora vascolare psammofila della Toscana
Checklist of the psammophilous vascular flora of Tuscany. An updated list of the psammophilous vascular flora occurring in coastal areas of Tuscany is presented. The list is based on bibliographic analysis and field studies effected ad hoc in the year 2012-2013. 704 specific and infraspecific taxa are reported (641 native). They belong to 383 genera and 90 families. Most represented families are Poaceae (13%), Asteraceae (12%), Fabaceae (10%), Caryophyllaceae (5%), Apiaceae (4%). 63 units are naturalized exotic species (about 9% of the flora). Aloe arborescens is a casual exotic newly recorded for Tuscany. The Italian endemics are 6, of which three are exclusive of sandy Tuscan coasts (Centaurea aplolepa Moretti subsp. subciliata (DC.) Arcang., Limonium etruscum Arrigoni & Rizzotto, Solidago litoralis Savi). Only 11 taxa were recorded in all or almost all the study areas: Ammophila arenaria (L.) Link subsp. arundinacea H.Lindb, Cakile maritima Scop. subsp. maritima, Calystegia soldanella (L.) Roem. & Schult., Echinophora spinosa L., Eryngium maritimum L., Kali tragus (L.) Scop. s.l., Lagurus ovatus L. subsp. ovatus, Medicago marina L., Pancratium maritimum L., Sporobolus virginicus Kunth
Spin gating electrical current
We use an aluminium single electron transistor with a magnetic gate to
directly quantify the chemical potential anisotropy of GaMnAs materials.
Uniaxial and cubic contributions to the chemical potential anisotropy are
determined from field rotation experiments. In performing magnetic field sweeps
we observe additional isotropic magnetic field dependence of the chemical
potential which shows a non-monotonic behavior. The observed effects are
explained by calculations based on the kinetic
exchange model of ferromagnetism in GaMnAs. Our device inverts the conventional
approach for constructing spin transistors: instead of spin-transport
controlled by ordinary gates we spin-gate ordinary charge transport.Comment: 5 pages, 4 figure
Reconfigurable Boolean Logic using Magnetic Single-Electron Transistors
We propose a novel hybrid single-electron device for reprogrammable low-power
logic operations, the magnetic single-electron transistor (MSET). The device
consists of an aluminium single-electron transistors with a GaMnAs magnetic
back-gate. Changing between different logic gate functions is realized by
reorienting the magnetic moments of the magnetic layer which induce a voltage
shift on the Coulomb blockade oscillations of the MSET. We show that we can
arbitrarily reprogram the function of the device from an n-type SET for
in-plane magnetization of the GaMnAs layer to p-type SET for out-of-plane
magnetization orientation. Moreover, we demonstrate a set of reprogrammable
Boolean gates and its logical complement at the single device level. Finally,
we propose two sets of reconfigurable binary gates using combinations of two
MSETs in a pull-down network
Presentation Based User Interfaces
This research will develop a methodology for designing user interfaces for general-purpose interactive systems. The central concept is the presentation, a structured pictorial or text object conveying information about some abstract object to the user. The methodology models a user interface as a shared communication medium, user and system communicating to each other by manipulating presentations.
The methodology stresses relations between presentations, especially presentations of the system itself; presentation manipulation by the user; presentation recognition by the system; and how properties of these establish a spectrum of interface styles.
The methodology suggests a general system base providing mechanisms to support construction of user interfaces. As part of an argument that such a base is feasible and valuable, and to demonstrate the domain independence of the methodology, three test systems will be implemented.MIT Artificial Intelligence Laborator
A human-oriented design process for collaborative robotics
The potential of collaborative robotics often does not materialize in an efficient design of the human-robot collaboration. Technology-oriented approaches are no longer enough in the Industry 4.0 era. This work proposes a set of methods to support manufacturing engineers in the human-oriented design process of integrated production systems to obtain satisfactory performance in the mass customization paradigm, without impacting the safety and health of workers. It founds the design criteria definition on five main pillars (safety, ergonomics, effectiveness, flexibility, and costs), favors the consideration of different design alternatives, and leads their selection. The dynamic impact of the design choices on the various elements of the system prevails over the static design constraints. The method has been experimented in collaboration with the major kitchen manufacturer in Italy, which introduced a collaborative robotics cell in the drawers' assembly line. It resulted in a more balanced production line (10% more), a verified risk minimization (RULA score reduced from 5 to 3 and OCRA score from 13.30 to 5.70), and a greater allocation of operators to high added value activities
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