793 research outputs found
A new fuzzy set merging technique using inclusion-based fuzzy clustering
This paper proposes a new method of merging parameterized fuzzy sets based on clustering in the parameters space, taking into account the degree of inclusion of each fuzzy set in the cluster prototypes. The merger method is applied to fuzzy rule base simplification by automatically replacing the fuzzy sets corresponding to a given cluster with that pertaining to cluster prototype. The feasibility and the performance of the proposed method are studied using an application in mobile robot navigation. The results indicate that the proposed merging and rule base simplification approach leads to good navigation performance in the application considered and to fuzzy models that are interpretable by experts. In this paper, we concentrate mainly on fuzzy systems with Gaussian membership functions, but the general approach can also be applied to other parameterized fuzzy sets
State estimation in quantum homodyne tomography with noisy data
In the framework of noisy quantum homodyne tomography with efficiency
parameter , we propose two estimators of a quantum state whose
density matrix elements decrease like , for
fixed known and . The first procedure estimates the matrix
coefficients by a projection method on the pattern functions (that we introduce
here for ), the second procedure is a kernel estimator of the
associated Wigner function. We compute the convergence rates of these
estimators, in risk
Approximate treatment of electron Coulomb distortion in quasielastic (e,e') reactions
In this paper we address the adequacy of various approximate methods of
including Coulomb distortion effects in (e,e') reactions by comparing to an
exact treatment using Dirac-Coulomb distorted waves. In particular, we examine
approximate methods and analyses of (e,e') reactions developed by Traini et al.
using a high energy approximation of the distorted waves and phase shifts due
to Lenz and Rosenfelder. This approximation has been used in the separation of
longitudinal and transverse structure functions in a number of (e,e')
experiments including the newly published 208Pb(e,e') data from Saclay. We find
that the assumptions used by Traini and others are not valid for typical (e,e')
experiments on medium and heavy nuclei, and hence the extracted structure
functions based on this formalism are not reliable. We describe an improved
approximation which is also based on the high energy approximation of Lenz and
Rosenfelder and the analyses of Knoll and compare our results to the Saclay
data. At each step of our analyses we compare our approximate results to the
exact distorted wave results and can therefore quantify the errors made by our
approximations. We find that for light nuclei, we can get an excellent
treatment of Coulomb distortion effects on (e,e') reactions just by using a
good approximation to the distorted waves, but for medium and heavy nuclei
simple additional ad hoc factors need to be included. We describe an explicit
procedure for using our approximate analyses to extract so-called longitudinal
and transverse structure functions from (e,e') reactions in the quasielastic
region.Comment: 30 pages, 8 figures, 16 reference
Transformations isotropes des germes de feuilletages holomorphes
AbstractGiven FÏ a germ of holomorphic singular foliation at the origin of Cn defined by an equation Ï=0 (with Ïâ§dÏ=0), we are interested in describing the group of isotropic transformations of FÏ, i.e., the group of those germs Ί of diffeomorphisms at the origin of Cn that satisfy ΊâÏâ§Ï=0
Gait speeds classifications by supervised modulation based machine-learning using Kinect camera
Early indication of some diseases such as Parkinson and Multiple Sclerosis often manifests with walking difficulties. Gait analysis provides vital information for assessing the walking patterns during the locomotion, especially when the outcomes are quantitative measures. This paper explores methods that can respond to the changes in the gait features during the swing stage using Kinect Camera, a low cost, marker-free, and portable device offered by Microsoft. Kinect has been exploited for tracking the skeletal positional data of body joints to assess and evaluate the gait performance. Linear kinematic gait features are extracted to discriminate between walking speeds by using five supervised modulation based machine-learning classifiers as follow: Decision Trees (DT), linear/nonlinear Support Vector Machines (SVMs), subspace discriminant and k-Nearest Neighbour (k-NN). The role of modulation techniques such as Frequency Modulation (FM) for increasing the efficiency of classifiers have been explored. The experimental results show that all five classifiers can successfully distinguish gait futures signal associated with walking patterns with high accuracy (average expected value of 86.19% with maximum of 92.9%). This validates the capability of the presented methodology in detecting key âindicatorsâ of health events.
Keywords: Gait Analysis, Kinematic Gait Features, Amplitude and Frequency Modulations, Baseband Signal, Passband Mapping, Machine-Learning, Classification Techniqu
Charge radii of the nucleon from its flavor dependent Dirac form factors
We have determined the proton and the neutron charge radii from a global
analysis of the proton and the neutron elastic form factors, after first
performing a flavor decomposition of these form factors under charge symmetry
in the light cone frame formulation. We then extracted the transverse
mean-square radii of the flavor dependent quark distributions. In turn, these
are related in a model-independent way to the proton and neutron charge radii
but allow us to take into account motion effects of the recoiling nucleon for
data at finite but high momentum transfer. In the proton case we find ,
consistent with the proton charge radius obtained from muonic hydrogen
spectroscopy \cite{pohl:2010,antog2013}. The current method improves on the
precision of the extraction based on the form factor
measurements. Furthermore, we find no discrepancy in the
determination among the different electron scattering measurements, all of
which, utilizing the current method of extraction, result in a value that is
consistent with the smallest extraction from the electron
scattering measurements \cite{Xiong:2019umf}. Concerning the neutron case, past
results relied solely on the neutron-electron scattering length measurements,
which suffer from an underestimation of underlying systematic uncertainties
inherent to the extraction technique. Utilizing the present method we have
performed the first extraction of the neutron charge radius based on nucleon
form factor data, and we find
EP-2044: Radiation-induced lung fibrosis is associated with M2 interstitial and hybrid alveolar macrophages
Assessment of the main stone fruit viruses and viroids in Algeria
In order to improve the sanitary status of the propagating material of stone fruits, a field survey was conducted to assess the main viruses and viroids affecting stone fruits in selected growing areas and their distribution on the collected material by using serological and molecular detection methods.Serological assays were carried out to detect Plum pox virus (PPV), Prunus necrotic ring spot virus (PNRSV), Prune dwarf virus (PDV), Apple mosaic virus (ApMV) and Apple chlorotic leaf spot virus (ACLSV). Moreover, tissue-print hybridization was performed to detect Peach latent mosaic viroid (PLMVd) and Hop stunt viroid (HSVd).Among nearly 2000 trees tested, no PPV infection was detected, while 14% of them positively reacted to at least one virus. The highest infection rate (18%) was reported in both nurseries and commercial orchards. PNRSV was the most detected virus (9%), followed by ApMV (3%) and PDV (1.5%). Cherry was the most infected species (20%). As for viroids, a high infection rate was recorded for PLMVd (9%) and HSVd (5%); the highest infection rate was reported in mother blocks and varietal collections.Keywords: Algeria, Prunus, virus, viroids, ELISA, tissue-print hybridization, sanitary statu
Eikonal analysis of Coulomb distortion in quasi-elastic electron scattering
An eikonal expansion is used to provide systematic corrections to the eikonal
approximation through order , where is the wave number. Electron
wave functions are obtained for the Dirac equation with a Coulomb potential.
They are used to investigate distorted-wave matrix elements for quasi-elastic
electron scattering from a nucleus. A form of effective-momentum approximation
is obtained using trajectory-dependent eikonal phases and focusing factors.
Fixing the Coulomb distortion effects at the center of the nucleus, the
often-used ema approximation is recovered. Comparisons of these approximations
are made with full calculations using the electron eikonal wave functions. The
ema results are found to agree well with the full calculations.Comment: 12 pages, 6 Postscript figure
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