Preferred Language
Articles
/
ZxcZqJEBVTCNdQwC0ZeT
Studying the Optical Properties of CdSe Quantum Dots Prepared by Colloidal Method with Different pH Values
...Show More Authors

Preview PDF
Quick Preview PDF
Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of Slice inverse regression with the principal components in reducing high-dimensions data by using simulation
...Show More Authors

This research aims to study the methods of reduction of dimensions that overcome the problem curse of dimensionality when traditional methods fail to provide a good estimation of the parameters So this problem must be dealt with directly . Two methods were used to solve the problem of high dimensional data, The first method is the non-classical method Slice inverse regression ( SIR ) method and the proposed weight standard Sir (WSIR) method and principal components (PCA) which is the general method used in reducing dimensions,    (SIR ) and (PCA) is based on the work of linear combinations of a subset of the original explanatory variables, which may suffer from the problem of heterogeneity and the problem of linear

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Oct 15 2014
Journal Name
International Journal Of Advanced Research
A survey/ Development of Passive Optical Access Networks Technologies
...Show More Authors

The bandwidth requirements of telecommunication network users increased rapidly during the last decades. Optical access technologies must provide the bandwidth demand for each user. The passive optical access networks (PONs) support a maximum data rate of 100 Gbps by using the Orthogonal Frequency Division Multiplexing (OFDM) technique in the optical access network. In this paper, the optical broadband access networks with many techniques from Time Division Multiplexing Passive Optical Networks (TDM PON) to Orthogonal Frequency Division Multiplex Passive Optical Networks (OFDM PON) are presented. The architectures, advantages, disadvantages, and main parameters of these optical access networks are discussed and reported which have many ad

... Show More
View Publication Preview PDF
Publication Date
Fri Jan 01 2016
Journal Name
Al-mustansiriyah Journal Of Science
Calculate optical parameters of ions beam from plasma source
...Show More Authors

Preview PDF
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Implementation of Optical Coherent Communication System between Two Computers
...Show More Authors

This work represents implementation and investigation of optical coherent communication system between two computers. A single mode optical fiber is selected as transmission medium. The data are sent via the RS-232 standard interface with a bit rate of 9.6 kbps from personal computer (PC1) by line receive to convert the data from electrical levels (-12/+12 V) into TTL level (0/5 V). The modulation of this data was accomplished by internal modulation using laser diode type (HFCT-5208M) 1310 nm wavelength. The optical D-coupler was used to combine the optical signal that come from laser source with optical signal of laser local oscillator (OTS-304XI) at 1310/1550 nm wavelength to obtain coherent (homodyne and heterodyne) detection respective

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu May 30 2024
Journal Name
Iraqi Journal Of Science
Plasma Optical Emission Spectroscopy Study of Some Iron Meteorites
...Show More Authors

This study aims to analyze spectra in real-time for λ Draconids, σ Hydrids, μ Virginid, and one sporadic meteor using spectroscopic chemical analysis and diagnose plasma parameters. Good-resolution spectroscopy and a CCD camera for meteor observation were used concurrently to examine the ablation spectra of these meteorites in situ. The Boltzmann and Lorentz methods were then used to determine the temperature and density of electrons, the length of Debye, and the frequency of plasma. Furthermore, spectra data can be analyzed and compared to data from other sources. Spectrum tests can be utilized to identify the chemical structure of meteorites' plasma.

Preview PDF
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Sun Dec 04 2011
Journal Name
Baghdad Science Journal
Dopping Effect on Optical Constant of Poly (Vinyl Chloride)
...Show More Authors

Thick films of poly(vinyl chloride)(PVC)& PVC doped with Zn(etx)2 salt complex have been prepared by cast method with fixed thickness almost (120±5) Microns. Optical studies were carried out in the wavelengths region(200-900)nm based on absorption & transmition measurement. Optical parameters such as absorption coefficient(?) ,refraction index(n) and extinction coefficient(K) were observed to be effected by adding the dopant.Electrical parameters such as real(?)& imaginary(?) part of dielectric constant were also calculated part of dielectric constant were also calculated from the optical parameters using Maxwell equation.

View Publication Preview PDF
Crossref
Publication Date
Tue Dec 01 2009
Journal Name
Iraqi Journal Of Physics
Simulation of an ion Optical Transport and Focusing System
...Show More Authors

A simulated ion/electron optical transport and focusing system has been put forward to
be mounted on high voltage transmission electron microscope for in situ investigations.
The suggested system consists of three axially symmetric electrostatic lenses namely an
einzel lens, an accelerating immersion lens, and a decelerating immersion lens, in addition
to an electrostatic quadrupole doublet lens placed on the image side. The electrodes
profile of these lenses is determined from the proposed axial field distributions. The
optical properties of the whole system have been computed together with the trajectory of
the accelerated charged-particles beam along the optical axis of the system. The computed
dimensions of th

... Show More
View Publication Preview PDF
Publication Date
Sun Mar 10 2024
Journal Name
Journal Of Optics
Optical signal transmission for the visible light communication system through the water–air interface link
...Show More Authors

View Publication
Scopus (2)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Tue Sep 08 2020
Journal Name
Baghdad Science Journal
A comparison among Different Methods for Estimating Regression Parameters with Autocorrelation Problem under Exponentially Distributed Error
...Show More Authors

Multiple linear regressions are concerned with studying and analyzing the relationship between the dependent variable and a set of explanatory variables. From this relationship the values of variables are predicted. In this paper the multiple linear regression model and three covariates were studied in the presence of the problem of auto-correlation of errors when the random error distributed the distribution of exponential. Three methods were compared (general least squares, M robust, and Laplace robust method). We have employed the simulation studies and calculated the statistical standard mean squares error with sample sizes (15, 30, 60, 100). Further we applied the best method on the real experiment data representing the varieties of

... Show More
View Publication Preview PDF
Scopus Clarivate Crossref
Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
Software Protection by Combining Hash Function with Hardware Identifications
...Show More Authors

This paper presents a hybrid software copy protection scheme, the scheme is applied to
prevent illegal copying of software by produce a license key which is unique and easy to
generate. This work employs the uniqueness of identification of hard disk in personal
computer which can get by software to create a license key after treated with SHA-1 one way
hash function. Two mean measures are used to evaluate the proposed method, complexity
and processing time, SHA-1 can insure the high complexity to deny the hackers for produce
unauthorized copies, many experiments have been executed using different sizes of software
to calculate the consuming time. The measures show high complexity and short execution
time for propos

... Show More
View Publication Preview PDF