1,557 research outputs found
Trapping effects on the vibration-inversion-rotation motions of an ammonia molecule encapsulated in C fullerene molecule
The infrared bar-spectrum of a single ammonia molecule encapsulated in
nano-cage C fullerene molecule is modelled using the site inclusion
model successfully applied to analyze spectra of CO isotopologues isolated
in rare gas matrix. Calculations show that NH can rotate freely on a sphere
of radius 0.184 around the site centre of the nano-cage and spin
freely about its C symmetry axis. In the static field inside the cage
degenerate and vibrational modes are blue shifted and split.
When dynamic coupling with translational motion is considered, the spectral
signature of the mode is modified with a higher hindering barrier (2451
cm), an effective reduced mass (6.569 g.mol) and a longer
tunneling time (55594 ps) for the fundamental level compared to gas-phase
values (2047 cm), (2.563 g.mol) and (20.85 ps). As a result this
mode is red shifted. Moreover, simulation shows that the changes in the
bar-spectrum of the latter mode can be used to probe the temperature of the
surrounding media in which fullerene is observed
Van't Hoff law for temperature dependent Langmuir constants in clathrate hydrate nanocavities
This work gives a van't Hoff law expression of Langmuir constants of
different species for determining their occupancy in the nanocavities of
clathrate hydrates. The van't Hoff law's parameters are derived from a fit with
Langmuir constants calculated using a pairwise site-site interaction potential
to model the anisotropic potential environment in the cavities, as a function
of temperature. The parameters can be used for calculating clathrates
compositions. Results are given for nineteen gas species trapped in the small
and large cavities of structure types I and II [1]. The accuracy of this
approach is based on a comparison with available experimental data for ethane
and cyclo- propane clathrate hydrates. The numerical method applied in this
work, was recently validated from a comparison with the spherical cell method
based on analytical considerations [1]Comment: 2 figure
Structure-Based Subspace Method for Multi-Channel Blind System Identification
In this work, a novel subspace-based method for blind identification of
multichannel finite impulse response (FIR) systems is presented. Here, we
exploit directly the impeded Toeplitz channel structure in the signal linear
model to build a quadratic form whose minimization leads to the desired channel
estimation up to a scalar factor. This method can be extended to estimate any
predefined linear structure, e.g. Hankel, that is usually encountered in linear
systems. Simulation findings are provided to highlight the appealing advantages
of the new structure-based subspace (SSS) method over the standard subspace
(SS) method in certain adverse identification scenarii.Comment: 5 pages, Submitted to IEEE Signal Processing Letters, January 201
XML Rewriting Attacks: Existing Solutions and their Limitations
Web Services are web-based applications made available for web users or
remote Web-based programs. In order to promote interoperability, they publish
their interfaces in the so-called WSDL file and allow remote call over the
network. Although Web Services can be used in different ways, the industry
standard is the Service Oriented Architecture Web Services that doesn't rely on
the implementation details. In this architecture, communication is performed
through XML-based messages called SOAP messages. However, those messages are
prone to attacks that can lead to code injection, unauthorized accesses,
identity theft, etc. This type of attacks, called XML Rewriting Attacks, are
all based on unauthorized, yet possible, modifications of SOAP messages. We
present in this paper an explanation of this kind of attack, review the
existing solutions, and show their limitations. We also propose some ideas to
secure SOAP messages, as well as implementation ideas
Left and right compatibility of strict orders with fuzzy tolerance and fuzzy equivalence relations
The notion of extensionality of a fuzzy relation w.r.t. a fuzzy equivalence was first introduced by Hohle and Blanchard. Belohlavek introduced a similar definition of compatibility of a fuzzy relation w.r.t. a fuzzy equality. In [14] we generalized this notion to left compatibility, right compatibility and compatibility of arbitrary fuzzy relations and we characterized them in terms of left and right traces introduced by Fodor. In this note, we will again investigate these notions, but this time we focus on the compatibility of strict orders with fuzzy tolerance and fuzzy equivalence relations
RELATIONSHIPS BETWEEN RECTILINEAR DIAMETER AMPLITUDES AND MOLECULAR POLARIZABILITIES OF FLUIDS NEAR THEIR CRITICAL POINTS
This work reports on the relationships that exist between the amplitudes of liquid-vapor average densities of several fluids and their molecular polarizabilities. The slope of the coexistence-curve diameter has been determined from an equation of state based on the crossover model. We found that the slope for each fluid near the critical point is directly correlated with its molecular polarizability. This correlation is the consequence of the three-body Axilrod-Teller interaction
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