2,410 research outputs found
Hybrid biomedical intelligent systems
"Copyright © 2012 Maysam Abbod et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited."The purpose of this special issue is to promote research and developments of the best work in the field of hybrid intelligent systems for biomedical applications
Large strain actuation in barium titanate single crystals under stress and electric field
Large strain actuation in barium titanate (BaTiO3) single crystals subjected to combined uniaxial stress and electric field is examined. A maximum strain of about 0.45% is measured under a combined loading of 2.7 MPa compressive stress and ±1.25 MVm-1 cyclic electric field. Above 2.7 MPa, the crystal does not cycle fully between the in-plane and out-of-plane polarized states due to large compressive stress, and consequently, a considerable reduction in actuation strain is apparent. The hysteresis evolution of the crystal under combined electromechanical loading reveals incomplete switching characteristics and a considerable disproportion of slope gradients at zero electric field for the measured polarization and strain hysteresis curves. A likely cause for the disproportion of slope gradients is the cooperative operation of multiple 90° switching systems by which “polarization-free” strain changes are induced
Generic Subsequence Matching Framework: Modularity, Flexibility, Efficiency
Subsequence matching has appeared to be an ideal approach for solving many
problems related to the fields of data mining and similarity retrieval. It has
been shown that almost any data class (audio, image, biometrics, signals) is or
can be represented by some kind of time series or string of symbols, which can
be seen as an input for various subsequence matching approaches. The variety of
data types, specific tasks and their partial or full solutions is so wide that
the choice, implementation and parametrization of a suitable solution for a
given task might be complicated and time-consuming; a possibly fruitful
combination of fragments from different research areas may not be obvious nor
easy to realize. The leading authors of this field also mention the
implementation bias that makes difficult a proper comparison of competing
approaches. Therefore we present a new generic Subsequence Matching Framework
(SMF) that tries to overcome the aforementioned problems by a uniform frame
that simplifies and speeds up the design, development and evaluation of
subsequence matching related systems. We identify several relatively separate
subtasks solved differently over the literature and SMF enables to combine them
in straightforward manner achieving new quality and efficiency. This framework
can be used in many application domains and its components can be reused
effectively. Its strictly modular architecture and openness enables also
involvement of efficient solutions from different fields, for instance
efficient metric-based indexes. This is an extended version of a paper
published on DEXA 2012.Comment: This is an extended version of a paper published on DEXA 201
Type-2 fuzzy sets applied to multivariable self-organizing fuzzy logic controllers for regulating anesthesia
In this paper, novel interval and general type-2 self-organizing fuzzy logic controllers (SOFLCs) are proposed for the automatic control of anesthesia during surgical procedures. The type-2 SOFLC is a hierarchical adaptive fuzzy controller able to generate and modify its rule-base in response to the controller's performance. The type-2 SOFLC uses type-2 fuzzy sets derived from real surgical data capturing patient variability in monitored physiological parameters during anesthetic sedation, which are used to define the footprint of uncertainty (FOU) of the type-2 fuzzy sets. Experimental simulations were carried out to evaluate the performance of the type-2 SOFLCs in their ability to control anesthetic delivery rates for maintaining desired physiological set points for anesthesia (muscle relaxation and blood pressure) under signal and patient noise. Results show that the type-2 SOFLCs can perform well and outperform previous type-1 SOFLC and comparative approaches for anesthesia control producing lower performance errors while using better defined rules in regulating anesthesia set points while handling the control uncertainties. The results are further supported by statistical analysis which also show that zSlices general type-2 SOFLCs are able to outperform interval type-2 SOFLC in terms of their steady state performance
Superconductivity from D3/D7: Holographic Pion Superfluid
We show that a D3/D7 system (at zero quark mass limit) at finite isospin
chemical potential goes through a superconductor (superfluid) like phase
transition. This is similar to a flavored superfluid phase studied in QCD
literature, where mesonic operators condensate. We have studied the frequency
dependent conductivity of the condensate and found a delta function pole in the
zero frequency limit. This is an example of superconductivity in a string
theory context. Consequently we have found a superfluid/supercurrent type
solution and studied the associated phase diagram. The superconducting
transition changes from second order to first order at a critical superfluid
velocity. We have studied various properties of the superconducting system like
superfluid density, energy gap, second sound etc. We investigate the
possibility of the isospin chemical potential modifying the embedding of the
flavor branes by checking whether the transverse scalars also condense at low
temperature. This however does not seem to be the case.Comment: 18 pages, 8 figures, revtex
Landau Levels, Magnetic Fields and Holographic Fermi Liquids
We further consider a probe fermion in a dyonic black hole background in
anti-de Sitter spacetime, at zero temperature, comparing and contrasting two
distinct classes of solution that have previously appeared in the literature.
Each class has members labeled by an integer n, corresponding to the n-th
Landau level for the fermion. Our interest is the study of the spectral
function of the fermion, interpreting poles in it as indicative of
quasiparticles associated with the edge of a Fermi surface in the
holographically dual strongly coupled theory in a background magnetic field H
at finite chemical potential. Using both analytical and numerical methods, we
explicitly show how one class of solutions naturally leads to an infinite
family of quasiparticle peaks, signaling the presence of a Fermi surface for
each level n. We present some of the properties of these peaks, which fall into
a well behaved pattern at large n, extracting the scaling of Fermi energy with
n and H, as well as the dispersion of the quasiparticles.Comment: 23 pages, 4 figures. Changed some of the terminology: non-separable
-> infinite-sum. Clarified the relationship between our ansatz and the
separable ansat
Thermoelastic Damping in Micro- and Nano-Mechanical Systems
The importance of thermoelastic damping as a fundamental dissipation
mechanism for small-scale mechanical resonators is evaluated in light of recent
efforts to design high-Q micrometer- and nanometer-scale electro-mechanical
systems (MEMS and NEMS). The equations of linear thermoelasticity are used to
give a simple derivation for thermoelastic damping of small flexural vibrations
in thin beams. It is shown that Zener's well-known approximation by a
Lorentzian with a single thermal relaxation time slightly deviates from the
exact expression.Comment: 10 pages. Submitted to Phys. Rev.
Coarse-Graining the Lin-Maldacena Geometries
The Lin-Maldacena geometries are nonsingular gravity duals to degenerate
vacuum states of a family of field theories with SU(2|4) supersymmetry. In this
note, we show that at large N, where the number of vacuum states is large,
there is a natural `macroscopic' description of typical states, giving rise to
a set of coarse-grained geometries. For a given coarse-grained state, we can
associate an entropy related to the number of underlying microstates. We find a
simple formula for this entropy in terms of the data that specify the geometry.
We see that this entropy function is zero for the original microstate
geometries and maximized for a certain ``typical state'' geometry, which we
argue is the gravity dual to the zero-temperature limit of the thermal state of
the corresponding field theory. Finally, we note that the coarse-grained
geometries are singular if and only if the entropy function is non-zero.Comment: 29 pages, LaTeX, 3 figures; v2 references adde
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Using Artificial Neural Network to Predict a Variety of Pathogenic Microorganisms
In this study, an electronic nose is used to record breathing data from healthy patients and pneumonia patients. The electronic nose records resistance data using a micro-array of 11 sensors. The recorded data is fed to Artificial Neural Network (ANN) which is used to train a model for detection of infections. The ANN has performed accurate classification which can be further developed to an online efficient pneumonia detection system. Initially, five patients’ data are used to build up the ANN model. Then, another two patients’ data are used to test the accuracy of the model. The results show that the model predicts the same outcome that is diagnosed by Taipei Medical University Hospital where samples have to be cultured to identify whether patients have pneumonia or not. In this preliminary study, ANN has achieved good results which can be further developed to an online efficient pneumonia detection system in the near future.Taiwan Carbon Nanotube Technology Corporatio
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