408 research outputs found
PERFORMANCE ANALYSIS USING CODE CONVERTER APPROACH AND THE APPLICATION OF APPROXIMATE ENTROPY AS POST CLASSIFIER FOR THE CLASSIFICATION OF EPILEPSY RISK LEVELS FROM EEG SIGNALS
ABSTRACTObjective: The electroencephalogram (EEG) is actually a measure of the cumulative firing of neurons in various parts of the brain. The EEG containsthe information with regard to the changes in the electrical potential of the brain which is obtained from a set of recording electrodes. The aim of thispaper is to give a performance analysis by considering the advantage of Code Converter technique and Approximated Entropy (ApEn) is used as a postclassifier for the classification of the epilepsy risk levels obtained from EEG signals.Methods: The Data Acquisition of EEG signals are done initially from the hospital. Then the code converter approach is presented, as working ondefinite alphabets is much easier when compared to that of working on numericals. Finally, ApEn is used as a Post Classifier for the classification ofepilepsy risk levels from EEG signals.Results: The Performance Index and Quality Values are the two important parameters that are used to assess the performance of the Code Convertersand the Classifier. The Perfect Classification rate of 83.94% is achieved along with an Accuracy of 91.97% and a Quality Value of 18.5.Conclusion: The computation of this procedure seems to be very simple and versatile. Future works may use different Dimensionality Reductiontechniques to analyze its performance with Approximated Entropy as Post Classifier.Keywords: Electroencephalogram signals, Code converter, Performance index, Quality values
'Schwinger Model' on the Fuzzy Sphere
In this paper, we construct a model of spinor fields interacting with
specific gauge fields on fuzzy sphere and analyze the chiral symmetry of this
'Schwinger model'. In constructing the theory of gauge fields interacting with
spinors on fuzzy sphere, we take the approach that the Dirac operator on
q-deformed fuzzy sphere is the gauged Dirac operator on fuzzy
sphere. This introduces interaction between spinors and specific one parameter
family of gauge fields. We also show how to express the field strength for this
gauge field in terms of the Dirac operators and alone. Using the path
integral method, we have calculated the point functions of this model and
show that, in general, they do not vanish, reflecting the chiral non-invariance
of the partition function.Comment: Minor changes, typos corrected, 18 pages, to appear in Mod. Phys.
Lett.
Massive Gauge Axion Fields
A gauge invariant formulation for the massive axion is considered. The axion
acquires mass through a topological term which couples a (pseudo)scalar and a
third rank antisymmetric tensor. Duality, local and canonical equivalences with
the non-gauge invariant proposal are established. The supersymmetric version of
the gauge invariant model is constructed.Comment: Final version. New references adde
Role of disulfides and sulfhydryl groups in agonist and antagonist binding in serotonin<SUB>1A</SUB> receptors from bovine hippocampus
1. The serotonin1A (5-HT1A) receptors are members of a superfamily of seven-transmembrane- domain receptors that couple to G-proteins. They appear to be involved in various behavioral and cognitive functions. Mutagenesis and modeling studies point out that the ligand-binding sites in serotonin receptors are located in the transmembrane domain. However, these binding sites are not very well characterized. Since disulfide bonds and sulfhydryl groups have been shown to play vital roles in the assembly, organization, and function of various G-protein-coupled receptors, we report here the effect of disulfide and sulfhydryl group modifications on the agonist and antagonist binding activity of 5- HT1A receptors from bovine hippocampus. 2. DTT or NEM treatment caused a concentration-dependent reduction in specific binding of the agonist and antagonist in 5-HT1A receptors from bovine hippocampal native and solubilized membranes. This is supported by a concomitant reduction in binding affinity. 3. Pretreatment of the receptor with unlabeled ligands prior to chemical modifications indicate that the majority of disulfides or sulfhydryl groups that undergo modification giving rise to inhibition in binding activity could be at the vicinity of the ligand-binding sites. 4. In addition, ligand-binding studies in presence of GTP-γ-S, a nonhydrolyzable analogue of GTP, indicate that sulfhydryl groups (and disulfide bonds to a lesser extent) are vital for efficient coupling between the 5-HT1A receptor and the G-protein. 5. Our results point out that disulfide bonds and sulfhydryl groups could play an important role in ligand binding in 5-HT1A receptors
Electrodynamics on -Minkowski space-time
In this paper, we derive Lorentz force and Maxwell's equations on
kappa-Minkowski space-time up to the first order in the deformation parameter.
This is done by elevating the principle of minimal coupling to non-commutative
space-time. We also show the equivalence of minimal coupling prescription and
Feynman's approach. It is shown that the motion in kappa space-time can be
interpreted as motion in a background gravitational field, which is induced by
this non-commutativity. In the static limit, the effect of kappa deformation is
to scale the electric charge. We also show that the laws of electrodynamics
depend on the mass of the charged particle, in kappa space-time.Comment: 16 pages,minor changes, paragraph added on page 13, two new
references added, to appear in Phys.Rev.
Gauge field theories with covariant star-product
A noncommutative gauge theory is developed using a covariant star-product
between differential forms defined on a symplectic manifold, considered as the
space-time. It is proven that the field strength two-form is gauge covariant
and satisfies a deformed Bianchi identity. The noncommutative Yang-Mills action
is defined using a gauge covariant metric on the space-time and its gauge
invariance is proven up to the second order in the noncommutativity parameter.Comment: Dedicated to Ioan Gottlieb on the occasion of his 80th birthday
anniversary. 12 page
Intelligent Buffer Management Algorithm to Prevent Packet loss in Mobile Adhoc Network
In a mobile ad hoc network, which is self-organized and operates without any fundamental infrastructure, packet transmission from the source node to the destination node is completed after sending the route request and route reply. A reliable path is then selected depending on the protocol choice. Data that the sender intends to deliver is broken up into packets and given sequence numbers before being transmitted over the channel. With the aid of an internal buffer that helps to receive packets and forward them to the next destination, each and every packet travels along the allotted path until it reaches its destination. If there is more traffic on the MANET, the buffer may overflow, which will result in packet loss during transmission.. The source node must retransmit to the destination if any packets were lost during the initial transfer. This article proposes the Intelligent Buffer Management (IBM) active buffer management algorithm to prevent such a scenario by enhancing the MANET nodes' buffers to prevent packet loss. The Network Simulator is used to help build this suggested approach, and the results are compared to those of the current buffer management method to show that IBM is superior
Abelian 2-form gauge theory: special features
It is shown that the four -dimensional (4D) free Abelian 2-form
gauge theory provides an example of (i) a class of field theoretical models for
the Hodge theory, and (ii) a possible candidate for the quasi-topological field
theory (q-TFT). Despite many striking similarities with some of the key
topological features of the two -dimensional (2D) free Abelian (and
self-interacting non-Abelian) gauge theories, it turns out that the 4D free
Abelian 2-form gauge theory is {\it not} an exact TFT. To corroborate this
conclusion, some of the key issues are discussed. In particular, it is shown
that the (anti-)BRST and (anti-)co-BRST invariant quantities of the 4D 2-form
Abelian gauge theory obey the recursion relations that are reminiscent of the
exact TFTs but the Lagrangian density of this theory is not found to be able to
be expressed as the sum of (anti-)BRST and (anti-)co-BRST exact quantities as
is the case with the {\it topological} 2D free Abelian (and self-interacting
non-Abelian) gauge theories.Comment: LaTeX, 23 pages, journal ref. give
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