1,290 research outputs found
A fully CNN based fingerprint recognition system
In this paper, a fully cellular neural networks (CNN) based fingerprint recognition system is introduced. The system includes a preprocessing phase where the input fingerprint image is enhanced and a recognition phase where the enhanced fingerprint image is matched with the fingerprints in the database. Both preprocessing and recognition phases are realized by means of CNN approaches. A novel application of skeletonization method is used to perform ridgeline thinning which improves the quality of the extracted lines for further processing, and hence increases the overall system performance
Conserved mass models with stickiness and chipping
We study a chipping model in one dimensional periodic lattice with continuous
mass, where a fixed fraction of the mass is chipped off from a site and
distributed randomly among the departure site and its neighbours; the remaining
mass sticks to the site. In the asymmetric version, the chipped off mass is
distributed among the site and the right neighbour, whereas in the symmetric
version the redistribution occurs among the two neighbours. The steady state
mass distribution of the model is obtained using a perturbation method for both
parallel and random sequential updates. In most cases, this perturbation theory
provides a steady state distribution with reasonable accuracy.Comment: 17 pages, 4 eps figure
The spectral shift function and Levinson's theorem for quantum star graphs
We consider the Schr\"odinger operator on a star shaped graph with edges
joined at a single vertex. We derive an expression for the trace of the
difference of the perturbed and unperturbed resolvent in terms of a Wronskian.
This leads to representations for the perturbation determinant and the spectral
shift function, and to an analog of Levinson's formula
Revealing instabilities in a generalized triadic supply network: a bifurcation analysis
Supply networks are exposed to instabilities and thus a high level of risk. To mitigate this risk, it is necessary to understand how instabilities are formed in supply networks. In this paper, we focus on instabilities in
inventory dynamics that develop due to the topology of the supply network. To be able to capture these topology-induced instabilities, we use a method called generalized modeling, a minimally specified modeling approach adopted from ecology. This method maps the functional dependencies of production rates on the inventory levels of different parts and products, which are imposed by the network topology, to a set of elasticity parameters. We perform a bifurcation analysis to investigate how these elasticities affect the stability. First, we show that dyads and serial supply chains are immune to topology-induced instabilities. In contrast, in a simple triadic network, where a supplier acts as both a first and a second tier supplier, we can identify instabilities that emerge from saddle-node, Hopf, and global homoclinic bifurcations. These bifurcations lead to different types of dynamical behavior, including exponential convergence to and divergence from a steady state, temporary oscillations around a steady state, and co-existence of different types of dynamics, depending on initial conditions. Finally, we discuss managerial implications of the results
Finite-size scaling for non-linear rheology of fluids confined in a small space
We perform molecular dynamics simulations in order to examine the rheological
transition of fluids confined in a small space. By performing finite-size
scaling analysis, we demonstrate that this rheological transition results from
the competition between the system size and the length scale of cooperative
particle motion.Comment: 4pages, 8 figure
Pluronic polymer capped biocompatible mesoporous silica nanocarriers
A facile self-assembly method is described to prepare PEGylated silica nanocarriers using hydrophobic mesoporous silica nanoparticles and a pluronic F127 polymer. Pluronic capped nanocarriers revealed excellent dispersibility in biological media with cyto- and blood compatibilities. © 2013 The Royal Society of Chemistry
Monte-Carlo simulation of neutron transmission through nanocomposite materials for neutron-optics applications
Nanocomposites enable us to tune parameters that are crucial for use of such
materials for neutron-optics applications such as diffraction gratings by
careful choice of properties such as species (isotope) and concentration of
contained nanoparticles. Nanocomposites for neutron optics have so far
successfully been deployed in protonated form, containing high amounts of H
atoms, which exhibit rather strong neutron absorption and incoherent
scattering. At a future stage of development, chemicals containing H could
be replaced by components with more favourable isotopes, such as H or
F. In this note, we present results of Monte-Carlo simulations of the
transmissivity of various nanocomposite materials for thermal and very-cold
neutron spectra. The results are compared to experimental transmission data.
Our simulation results for deuterated and fluorinated nanocomposite materials
predict a decrease of absorption- and scattering-losses down to about 2 % for
very-cold neutrons.Comment: submitted to NIM
Indium rich InGaN solar cells grown by MOCVD
Cataloged from PDF version of article.This study focuses on both epitaxial growths of InxGa1-xN epilayers with graded In content, and the performance of solar cells structures grown on sapphire substrate by using metal organic chemical vapor deposition. The high resolution X-ray and Hall Effect characterization were carried out after epitaxial InGaN solar cell structures growth. The In content of the graded InGaN layer was calculated from the X-ray reciprocal space mapping measurements. Indium contents of the graded InGaN epilayers change from 8.8 to 7.1 % in Sample A, 15.7-7.1 % in Sample B, and 26.6-15.1 % in Sample C. The current voltage measurements of the solar cell devices were carried out after a standard micro fabrication procedure. Sample B exhibits better performance with a short-circuit current density of 6 mA/cm(2), open-circuit voltage of 0.25 V, fill factor of 39.13 %, and the best efficiency measured under a standard solar simulator with one-sun air mass 1.5 global light sources (100 mW/cm(2)) at room temperature for finished devices was 0.66 %
Surface Roughness and Effective Stick-Slip Motion
The effect of random surface roughness on hydrodynamics of viscous
incompressible liquid is discussed. Roughness-driven contributions to
hydrodynamic flows, energy dissipation, and friction force are calculated in a
wide range of parameters. When the hydrodynamic decay length (the viscous wave
penetration depth) is larger than the size of random surface inhomogeneities,
it is possible to replace a random rough surface by effective stick-slip
boundary conditions on a flat surface with two constants: the stick-slip length
and the renormalization of viscosity near the boundary. The stick-slip length
and the renormalization coefficient are expressed explicitly via the
correlation function of random surface inhomogeneities. The effective
stick-slip length is always negative signifying the effective slow-down of the
hydrodynamic flows by the rough surface (stick rather than slip motion). A
simple hydrodynamic model is presented as an illustration of these general
hydrodynamic results. The effective boundary parameters are analyzed
numerically for Gaussian, power-law and exponentially decaying correlators with
various indices. The maximum on the frequency dependence of the dissipation
allows one to extract the correlation radius (characteristic size) of the
surface inhomogeneities directly from, for example, experiments with torsional
quartz oscillators.Comment: RevTeX4, 14 pages, 3 figure
AWARENESS LEVEL OF LEADER WOMEN FARMERS ABOUT ORGANIC LIVESTOCK
Intensive livestock animal production has been preferred in order to meet food requirements of increasing population since 1950’s. However, especially in baby foods, organic farming products are getting preferred because of any harmfull supplements in natural conditions. Organic farming is getting popular because of increasing demand for natural foods especially in baby foods and higher incomed peoples. At the same time, organic animal products are being preferred as a new trend. Lack of environmental pollutants, large scale of agricultural lands and the presence of native breed livestock animals provide the significant opportunities for the promotion of organic livestock in Turkey. However, Turkey has not met the demand for animal products produced as organic. Small scale livestock enterprise, low education level and inefficient producer organizations are lead to this results. In this study, awareness level of the leader women farmers who have higher education and leadership skills than the other women farmers on organic livestock animal production was determined
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