22,648 research outputs found
Experimental investigation of open-ended microwave oven assisted encapsulation process
An open ended microwave oven is presented with improved uniform heating, heating rates and power conversion efficiency. This next generation oven produces more uniform EM fields in the evanescent region forming part of the heating area of the oven. These fields are vital for the rapid and uniform heating of various electromagnetically lossy materials. A fibre optic temperature sensor and an IR pyrometer are used to measure in situ and in real-time the temperature of the curing materials. An automatic computer controlled closed feedback loop measures the temperature in the curing material and drives the microwave components to
obtain predetermined curing temperature cycles for efficient curing. Uniform curing of the lossy encapsulants
is achieved with this oven with typical cure cycle of 270
seconds with a ramp rate of 1oC/s and a hold period of 2
minutes. Differential scanning calorimeter based measurement for the pulsed microwave based curing of
the polymer dielectric indicates a ~ 100% degree of cure
Non-Gaussian statistics and extreme waves in a nonlinear optical cavity
A unidirectional optical oscillator is built by using a liquid crystal
light-valve that couples a pump beam with the modes of a nearly spherical
cavity. For sufficiently high pump intensity, the cavity field presents a
complex spatio-temporal dynamics, accompanied by the emission of extreme waves
and large deviations from the Gaussian statistics. We identify a mechanism of
spatial symmetry breaking, due to a hypercycle-type amplification through the
nonlocal coupling of the cavity field
Transport-Health Equity Outcomes from mobile phone location data - a case study
The digital media convergence has innovated all the information and communication channels. ICTs have adapted to the reticular structure, which can be interpreted as a paradigm of today's Network Society, invoking a reorganization of man-machine relationship, interpersonal interactions and the ways of collecting, processing and storing data. Political communication and its processes of participation are not exempt from this evident change. The aim of this paper is to investigate the transformation dynamics that have taken place through the Internet and social networks, as effectively more democratic tools that are able to stimulate a bottom-up and grassroots participation, in some respects a disintermediate participation compared to the typical unidirectionality of analogue media. In identifying the specific characteristics of the interaction spaces offered by the web, we have examined the digital campaign strategy devised by the political parties during the Italian general election (4th March 2018). The results have returned an unprecedented scenario, in which the social media strategy plays a leading role in the different dimensions of political marketing. The web is proposed to become the ideal social arena for the meeting between political offer and demand
Scaling of Wave-Packet Dynamics in an Intense Midinfrared Field
A theoretical investigation is presented that examines the wavelength scaling from near-visible (0.8 µm) to midinfrared (2 µm) of the photoelectron distribution and high harmonics generated by a "single" atom in an intense electromagnetic field. The calculations use a numerical solution of the time-dependent Schrödinger equation (TDSE) in argon and the strong-field approximation in helium. The scaling of electron energies (λ^2), harmonic cutoff (λ^2), and attochirp (λ^-1) agree with classical mechanics, but it is found that, surprisingly, the harmonic yield follows a λ^-(5-6) scaling at constant intensity. In addition, the TDSE results reveal an unexpected contribution from higher-order returns of the rescattering electron wave packet
New Formulation of Causal Dissipative Hydrodynamics: Shock wave propagation
The first 3D calculation of shock wave propagation in a homogeneous QGP has
been performed within the new formulation of relativistic dissipative
hydrodynamics which preserves the causality. We found that the relaxation time
plays an important role and also affects the angle of Mach cone.Comment: 4 pages, 1 figure, Proceedings of Quark Matter 200
Practical free-space quantum key distribution over 1 km
A working free-space quantum key distribution (QKD) system has been developed
and tested over an outdoor optical path of ~1 km at Los Alamos National
Laboratory under nighttime conditions. Results show that QKD can provide secure
real-time key distribution between parties who have a need to communicate
secretly. Finally, we examine the feasibility of surface to satellite QKD.Comment: 5 pages, 2 figures, 2 tables. Submitted to Physics Review Letters,
May 199
Cyclotron resonance of the quasi-two-dimensional electron gas at Hg1-xCdxTe grain boundaries
The magnetotransmission of a p-type Hg0.766Cd0.234Te bicrystal containing a single grain boundary with an inversion layer has been investigated in the submillimetre wavelength range. For the first time the cyclotron resonance lines belonging to the various electric subbands of a quasi-two-dimensional carrier system at a grain boundary could be detected. The measured cyclotron masses and the subband densities determined from Shubnikov-de Haas experiments are compared with theoretical predictions and it is found that the data can be explained very well within the framework of a triangular well approximation model which allows for non-parabolic effects
Broad band X-ray spectral properties of Gamma-ray bursts with BeppoSAX
In about one year, five gamma-ray bursts were simultaneously observed with
the Wide Field Cameras and Gamma Ray Burst Monitor aboard the BeppoSAX
satellite. From some of them X-ray afterglow emission has been clearly detected
with the same satellite. In order to understand how GRB emission is related to
the X-ray afterglow, we are performing a systematic study of the spectral
properties of these events. We report here preliminary results of this study.Comment: 5 pages, 3 figures. To appear in the Proceedings of the 4th
Huntsville Gamma-ray Burst Symposiu
Exploring the properties of the phases of QCD matter - research opportunities and priorities for the next decade
This document provides a summary of the discussions during the recent joint
QCD Town Meeting at Temple University of the status of and future plans for the
research program of the relativistic heavy-ion community. A list of compelling
questions is formulated, and a number of recommendations outlining the greatest
research opportunities and detailing the research priorities of the heavy-ion
community, voted on and unanimously approved at the Town Meeting, are
presented. They are supported by a broad discussion of the underlying physics
and its relation to other subfields. Areas of overlapping interests with the
"QCD and Hadron Structure" ("cold QCD") subcommunity, in particular the
recommendation for the future construction of an Electron-Ion Collider, are
emphasized. The agenda of activities of the "hot QCD" subcommunity at the Town
Meeting is attached.Comment: 34 pages of text, 254 references,16 figure
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