1,847 research outputs found
Quasideterminant solutions of a non-Abelian Hirota-Miwa equation
A non-Abelian version of the Hirota-Miwa equation is considered. In an
earlier paper [Nimmo (2006) J. Phys. A: Math. Gen. \textbf{39}, 5053-5065] it
was shown how solutions expressed as quasideterminants could be constructed for
this system by means of Darboux transformations. In this paper we discuss these
solutions from a different perspective and show that the solutions are
quasi-Pl\"{u}cker coordinates and that the non-Abelian Hirota-Miwa equation may
be written as a quasi-Pl\"{u}cker relation. The special case of the matrix
Hirota-Miwa equation is also considered using a more traditional, bilinear
approach and the techniques are compared
Matrix solutions of a noncommutative KP equation and a noncommutative mKP equation
Matrix solutions of a noncommutative KP and a noncommutative mKP equation
which can be expressed as quasideterminants are discussed. In particular, we
investigate interaction properties of two-soliton solutions.Comment: 2 figure
Building the field of health policy and systems research: framing the questions.
In the first of a series of articles addressing the current challenges and opportunities for the development of Health Policy & Systems Research (HPSR), Kabir Sheikh and colleagues lay out the main questions vexing the field
Logarithmic behavior of degradation dynamics in metal--oxide semiconductor devices
In this paper the authors describe a theoretical simple statistical modelling
of relaxation process in metal-oxide semiconductor devices that governs its
degradation. Basically, starting from an initial state where a given number of
traps are occupied, the dynamics of the relaxation process is measured
calculating the density of occupied traps and its fluctuations (second moment)
as function of time. Our theoretical results show a universal logarithmic law
for the density of occupied traps , i.e., the degradation is logarithmic and its amplitude depends on the
temperature and Fermi Level of device. Our approach reduces the work to the
averages determined by simple binomial sums that are corroborated by our Monte
Carlo simulations and by experimental results from literature, which bear in
mind enlightening elucidations about the physics of degradation of
semiconductor devices of our modern life
On a direct approach to quasideterminant solutions of a noncommutative KP equation
A noncommutative version of the KP equation and two families of its solutions
expressed as quasideterminants are discussed. The origin of these solutions is
explained by means of Darboux and binary Darboux transformations. Additionally,
it is shown that these solutions may also be verified directly. This approach
is reminiscent of the wronskian technique used for the Hirota bilinear form of
the regular, commutative KP equation but, in the noncommutative case, no
bilinearising transformation is available.Comment: 11 page
Short-Pulse, Compressed Ion Beams at the Neutralized Drift Compression Experiment
We have commenced experiments with intense short pulses of ion beams on the
Neutralized Drift Compression Experiment (NDCX-II) at Lawrence Berkeley
National Laboratory, with 1-mm beam spot size within 2.5 ns full-width at half
maximum. The ion kinetic energy is 1.2 MeV. To enable the short pulse duration
and mm-scale focal spot radius, the beam is neutralized in a 1.5-meter-long
drift compression section following the last accelerator cell. A
short-focal-length solenoid focuses the beam in the presence of the volumetric
plasma that is near the target. In the accelerator, the line-charge density
increases due to the velocity ramp imparted on the beam bunch. The scientific
topics to be explored are warm dense matter, the dynamics of radiation damage
in materials, and intense beam and beam-plasma physics including select topics
of relevance to the development of heavy-ion drivers for inertial fusion
energy. Below the transition to melting, the short beam pulses offer an
opportunity to study the multi-scale dynamics of radiation-induced damage in
materials with pump-probe experiments, and to stabilize novel metastable phases
of materials when short-pulse heating is followed by rapid quenching. First
experiments used a lithium ion source; a new plasma-based helium ion source
shows much greater charge delivered to the target.Comment: 4 pages, 2 figures, 1 table. Submitted to the proceedings for the
Ninth International Conference on Inertial Fusion Sciences and Applications,
IFSA 201
The EU and Asia within an evolving global order: what is Europe? Where is Asia?
The papers in this special edition are a very small selection from those presented at the EU-NESCA (Network of European Studies Centres in Asia) conference on "the EU and East Asia within an Evolving Global Order: Ideas, Actors and Processes" in November 2008 in Brussels. The conference was the culmination of three years of research activity involving workshops and conferences bringing together scholars from both regions primarily to discuss relations between Europe and Asia, perceptions of Europe in Asia, and the relationship between the European regional project and emerging regional forms in Asia. But although this was the last of the three major conferences organised by the consortium, it in many ways represented a starting point rather than the end; an opportunity to reflect on the conclusions of the first phase of collaboration and point towards new and continuing research agendas for the future
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