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Enhancing association rules algorithms for mining distributed databases. Integration of fast BitTable and multi-agent association rules mining in distributed medical databases for decision support.
Over the past few years, mining data located in heterogeneous and geographically distributed sites have been designated as one of the key important issues. Loading distributed data into centralized location for mining interesting rules is not a good approach. This is because it violates common issues such as data privacy and it imposes network overheads. The situation becomes worse when the network has limited bandwidth which is the case in most of the real time systems. This has prompted the need for intelligent data analysis to discover the hidden information in these huge amounts of distributed databases.
In this research, we present an incremental approach for building an efficient Multi-Agent based algorithm for mining real world databases in geographically distributed sites. First, we propose the Distributed Multi-Agent Association Rules algorithm (DMAAR) to minimize the all-to-all broadcasting between distributed sites. Analytical calculations show that DMAAR reduces the algorithm complexity and minimizes the message communication cost. The proposed Multi-Agent based algorithm complies with the Foundation for Intelligent Physical Agents (FIPA), which is considered as the global standards in communication between agents, thus, enabling the proposed algorithm agents to cooperate with other standard agents.
Second, the BitTable Multi-Agent Association Rules algorithm (BMAAR) is proposed. BMAAR includes an efficient BitTable data structure which helps in compressing the database thus can easily fit into the memory of the local sites. It also includes two BitWise AND/OR operations for quick candidate itemsets generation and support counting. Moreover, the algorithm includes three transaction trimming techniques to reduce the size of the mined data.
Third, we propose the Pruning Multi-Agent Association Rules algorithm (PMAAR) which includes three candidate itemsets pruning techniques for reducing the large number of generated candidate itemsets, consequently, reducing the total time for the mining process.
The proposed PMAAR algorithm has been compared with existing Association Rules algorithms against different benchmark datasets and has proved to have better performance and execution time. Moreover, PMAAR has been implemented on real world distributed medical databases obtained from more than one hospital in Egypt to discover the hidden Association Rules in patientsÂż records to demonstrate the merits and capabilities of the proposed model further. Medical data was anonymously obtained without the patientsÂż personal details. The analysis helped to identify the existence or the absence of the disease based on minimum number of effective examinations and tests. Thus, the proposed algorithm can help in providing accurate medical decisions based on cost effective treatments, improving the medical service for the patients, reducing the real time response for the health system and improving the quality of clinical decision making
Melt Electrospinning Designs for Nanofiber Fabrication for Different Applications
Nanofibers have been attracting growing attention owing to their outstanding physicochemical and structural properties as well as diverse and intriguing applications. Electrospinning has been known as a simple, flexible, and multipurpose technique for the fabrication of submicro scale fibers. Throughout the last two decades, numerous investigations have focused on the employment of electrospinning techniques to improve the characteristics of fabricated fibers. This review highlights the state of the art of melt electrospinning and clarifies the major categories based on multitemperature control, gas assist, laser melt, coaxial, and needleless designs. In addition, we represent the effect of melt electrospinning process parameters on the properties of produced fibers. Finally, this review summarizes the challenges and obstacles connected to the melt electrospinning technique.Scopu
Effects of the galactic magnetic field upon large scale anisotropies of extragalactic Cosmic Rays
The large scale pattern in the arrival directions of extragalactic cosmic
rays that reach the Earth is different from that of the flux arriving to the
halo of the Galaxy as a result of the propagation through the galactic magnetic
field. Two different effects are relevant in this process: deflections of
trajectories and (de)acceleration by the electric field component due to the
galactic rotation. The deflection of the cosmic ray trajectories makes the flux
intensity arriving to the halo from some direction to appear reaching the Earth
from another direction. This applies to any intrinsic anisotropy in the
extragalactic distribution or, even in the absence of intrinsic anisotropies,
to the dipolar Compton-Getting anisotropy induced when the observer is moving
with respect to the cosmic rays rest frame. For an observer moving with the
solar system, cosmic rays traveling through far away regions of the Galaxy also
experience an electric force coming from the relative motion (due to the
rotation of the Galaxy) of the local system in which the field can be
considered as being purely magnetic. This produces small changes in the
particles momentum that can originate large scale anisotropies even for an
isotropic extragalactic flux.Comment: 11 pages, 4 figure
Relative locality: A deepening of the relativity principle
We describe a recently introduced principle of relative locality which we
propose governs a regime of quantum gravitational phenomena accessible to
experimental investigation. This regime comprises phenomena in which
and may be neglected, while their ratio, the Planck mass , is important. We propose that governs the scale at
which momentum space may have a curved geometry. We find that there are
striking consequences for the concept of locality. The description of events in
spacetime now depends on the energy used to probe it. But there remains an
invariant description of physics in phase space. There is furthermore a
reasonable expectation that the geometry of momentum space can be measured
experimentally using astrophysical observations.Comment: 8 pages, Latex; this essay was awarded Second Prize in the 2011 Essay
Competition of the Gravity Research Foundatio
On the true nature of renormalizability in Horava-Lifshitz gravity
We argue that the true nature of the renormalizability of Horava-Lifshitz
gravity lies in the presence of higher order spatial derivatives and not in the
anisotropic Lifshitz scaling of space and time. We discuss the possibility of
constructing a higher order spatial derivatives model that has the same
renormalization properties of Horava-Lifshitz gravity but that does not make
use of the Lifshitz scaling. In addition, the state-of-the-art of the Lorentz
symmetry restoration in Horava-Lifshitz-type theories of gravitation is
reviewed.Comment: Latex file in Revtex style, 5 pages, no figures. v2: references
added, version accepted for publication in Foundations of Physic
The Contribution of Fermi Gamma-Ray Pulsars to the local Flux of Cosmic-Ray Electrons and Positrons
We analyze the contribution of gamma-ray pulsars from the first Fermi-Large
Area Telescope (LAT) catalogue to the local flux of cosmic-ray electrons and
positrons (e+e-). We present new distance estimates for all Fermi gamma-ray
pulsars, based on the measured gamma-ray flux and pulse shape. We then estimate
the contribution of gamma-ray pulsars to the local e+e- flux, in the context of
a simple model for the pulsar e+e- emission. We find that 10 of the Fermi
pulsars potentially contribute significantly to the measured e+e- flux in the
energy range between 100 GeV and 1 TeV. Of the 10 pulsars, 2 are old EGRET
gamma-ray pulsars, 2 pulsars were discovered with radio ephemerides, and 6 were
discovered with the Fermi pulsar blind-search campaign. We argue that known
radio pulsars fall in regions of parameter space where the e+e- contribution is
predicted to be typically much smaller than from those regions where Fermi-LAT
pulsars exist. However, comparing the Fermi gamma-ray flux sensitivity to the
regions of pulsar parameter space where a significant e+e- contribution is
predicted, we find that a few known radio pulsars that have not yet been
detected by Fermi can also significantly contribute to the local e+e- flux if
(i) they are closer than 2 kpc, and if (ii) they have a characteristic age on
the order of one mega-year.Comment: 21 pages, 6 figures, accepted for publication in JCA
Understanding hadronic gamma-ray emission from supernova remnants
We aim to test the plausibility of a theoretical framework in which the
gamma-ray emission detected from supernova remnants may be of hadronic origin,
i.e., due to the decay of neutral pions produced in nuclear collisions
involving relativistic nuclei. In particular, we investigate the effects
induced by magnetic field amplification on the expected particle spectra,
outlining a phenomenological scenario consistent with both the underlying
Physics and the larger and larger amount of observational data provided by the
present generation of gamma experiments, which seem to indicate rather steep
spectra for the accelerated particles. In addition, in order to study to study
how pre-supernova winds might affect the expected emission in this class of
sources, the time-dependent gamma-ray luminosity of a remnant with a massive
progenitor is worked out. Solid points and limitations of the proposed scenario
are finally discussed in a critical way.Comment: 30 pages, 5 figures; Several comments, references and a figure added.
Some typos correcte
Pharmacological, nutritional and antimicrobial uses of Moringa oleifera Lam. leaves in poultry nutrition: An updated knowledge
Recently, developing countries have focused on using innovative feed in poultry nutrition. The plant Moringa oleifera is native to India but grows worldwide in tropical and subtropical climates. Moringa is planted on a large scale as it can tolerate severe dry and cold conditions. All parts of this plant can be used for commercial or nutritional purposes, and it has a favorable nutritional profile. Beneficial phytochemicals, minerals, and vitamins are abundant in the leaves. The leaf extracts can be used to treat malnutrition; they also possess anticancer, antioxidant, antidiabetic, antibacterial, and anti-inflammatory properties. Further, moringa contains antinutritional substances, such as trypsin inhibitors, phytates, tannins, oxalates, cyanide, and saponins, which have a harmful effect on mineral and protein metabolism. Previous research suggested that including moringa in chicken diets boosts their growth and productivity. Therefore, this review focuses on the characterization and application of M. oleifera in poultry nutrition and its potential toxicity. Furthermore, we discuss the nutritional content, phytochemicals, and antioxidants of M. oleifera leaf meal and its applicability in poultry rations
Background Dependent Lorentz Violation: Natural Solutions to the Theoretical Challenges of the OPERA Experiment
To explain both the OPERA experiment and all the known phenomenological
constraints/observations on Lorentz violation, the Background Dependent Lorentz
Violation (BDLV) has been proposed. We study the BDLV in a model independent
way, and conjecture that there may exist a "Dream Special Relativity Theory",
where all the Standard Model (SM) particles can be subluminal due to the
background effects. Assuming that the Lorentz violation on the Earth is much
larger than those on the interstellar scale, we automatically escape all the
astrophysical constraints on Lorentz violation. For the BDLV from the effective
field theory, we present a simple model and discuss the possible solutions to
the theoretical challenges of the OPERA experiment such as the Bremsstrahlung
effects for muon neutrinos and the pion decays. Also, we address the Lorentz
violation constraints from the LEP and KamLAMD experiments. For the BDLV from
the Type IIB string theory with D3-branes and D7-branes, we point out that the
D3-branes are flavour blind, and all the SM particles are the conventional
particles as in the traditional SM when they do not interact with the
D3-branes. Thus, we not only can naturally avoid all the known phenomenological
constraints on Lorentz violation, but also can naturally explain all the
theoretical challenges. Interestingly, the energy dependent photon velocities
may be tested at the experiments.Comment: RevTex4, 14 pages, minor corrections, references adde
Constraining Sources of Ultra High Energy Cosmic Rays Using High Energy Observations with the Fermi Satellite
We analyze the conditions that enable acceleration of particles to ultra-high
energies, ~10^{20} eV (UHECRs). We show that broad band photon data recently
provided by WMAP, ISOCAM, Swift and Fermi satellites, yield constraints on the
ability of active galactic nuclei (AGN) to produce UHECRs. The high energy (MeV
- GeV) photons are produced by Compton scattering of the emitted low energy
photons and the cosmic microwave background or extra-galactic background light.
The ratio of the luminosities at high and low photon energies can therefore be
used as a probe of the physical conditions in the acceleration site. We find
that existing data excludes core regions of nearby radio-loud AGN as possible
acceleration sites of UHECR protons. However, we show that giant radio lobes
are not excluded. We apply our method to Cen A, and show that acceleration of
protons to ~10^{20} eV can only occur at distances >~ 100 kpc from the core.Comment: Extended discussion on former results; Accepted for publication in
JCA
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