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Optical Power Distributions for 4×4 MIMO Visible Light Communications in Indoor Environment
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Visible Light Communication (VLC) has emerged as a powerful technique for wireless communication systems. Providing high data rate and increasing capacity are the major problems in VLC. Recent evidence suggests that Multiple Input Multiple Output (MIMO) technique can offers improved data rates and increased link range. This paper describes the design and implementation of visible light communication system in indoor environment exploring the benefits of MIMO. The specific objective of this research was to implement a 4× 4 Multiple Input (LEDs) Multiple Output (photodetectors)-VLC communication system, where a 16 white power LEDs in four arrays are setting up at transmitter and four RX modules are setting up at receiver side without the need for additional power or bandwidth as well as analyze a mathematical model for a VLC-× 4 MIMO with different modes such as the suitable angles to cover the entire room. The research designs practically an electronic circuit for the transmitter and receiver with inexpensive components. The power distribution of different propagation modes is calculated for Single Input Single Output (SISO) and MIMO channels in typical room dimensions. The results in this paper indicate that the power is distributed uniformly for entire room when implemented VLC-MIMO as compared to VLC-SISO. Furthermore, a 4× 4 MIMO implementing VLC is compared in term of BER vs. SINR with SISO communication system for both Line of Sight (LOS) and Non Line of Sight (NLOS) propagation modes. Comparing the two results of LOS and NLOS, it can be seen that a 4× 4 MIMO implementing VLC for LOS perform better …

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Publication Date
Wed Mar 16 2022
Journal Name
Journal Of Educational And Psychological Researches
The Degree to Which Princess Rahma University College Students Possess E-Learning Skills Related to Moodle from their Point of View, in Light of the Corona Crisis
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This study aims to identify the degree of students of Princess Rahma University College owning e-learning skills related to MOODLE as they perceived in the of light Corona crisis. The researchers' questionnaire consisted of (37) items, distributed in three areas of e-learning skills related to the MOODLE on (147) students were chosen randomly. The results of the study showed that the degree of students 'possession of e-learning skills related to the MOODLE was significant. The results also revealed that there were statistically significant differences in the degree of students' possession of electronic learning skills related to the MOODLE due to sex in favor of females. Finally, there were no statistically significant differences in the

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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Educational And Psychological Researches
The social responsibility to the visual media and its role in spreading the culture of the environment protection / field research to a sample of students of the University of Baghdad
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        This paper deals with social responsibility visible to the media and the role they play in spreading the culture of environmental protection, and make research on a sample of the University of Baghdad consisting students from 150 students, male and female were distributed questionnaire form on the sample to obtain the required information has been questionnaire included axes distributed questions achieve the objectives of the search, and after the form data were analyzed using statistical program spss results show that the visual media and its role in spreading the culture of environmental protection form averages arithmetic high, indicating a rise in the influence of th

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Publication Date
Mon Jun 01 2020
Journal Name
Iraqi Journal Of Physics
Optical and structural properties of synthesized ZnO nanorods through chemical bath deposition on various substrates
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Chemical bath deposition was used to synthesize ZnO nanorods (NRs) on glass and fluorine_doped tin oxide (FTO) substrates. X-ray diffraction was performed to examine the crystallinity of ZnO nanorod. Results showed that ZnO NRs had a wurtzite crystal structure. Field emission scanning electron microscopy images showed that glass sample had rod-like structure distribution with (50 nm) diameter and average length of approximately (700 nm), whereas the FTO-coated glass sample had 25 nm diameter and average length of approximately 950 nm. The direct optical transition band gaps of the glass and FTO_coated glass samples were( 4 and 4.43 eV), respectively. The structural and optical properties of the synthesized ZnO p

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Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
The structure and optical properties of organic semiconductor bulk hetrojunction blend (NiPcTs/Alq3) thin films
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The effect of heat treatment on the optical properties of the bulk heterojunction blend nickel (II) phthalocyanine tetrasulfonic acid tetrasodium salt and Tris (8-hydroxyquinolinato) Aluminum (NiPcTs/Alq3) thin films which prepared by spin coating was described in this study. The films coated on a glass substrate with speed of 1500 rpm for 1.5 min and treated with different annealing temperature (373, 423 and 473) K. The samples characterized using UV-Vis, X ray diffraction and Fourier transform Infrared (FTIR) spectra, XRD patterns indicated the presence of amorphous and polycrystalline blend (NiPcTs/Alq3). The results of UV visible shows that the band gap increase with increasing the annealing temperature up to 373 K and decreases with

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Publication Date
Thu Mar 09 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Structural and Optical Properties of Zinc Telluride Thin Films by Vacuum Thermal Evaporation Technique
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Different thicknesseses of polycrystalline ZnTe films have been deposited on to glass substrates by vacuum evaporation technique under vacuum 2.1x10-5 mbar. The structural characteristics studied by X-ray diffraction (XRD) showed that the films are polycrystalline and have a cubic (zinc blende ) structure. The calculated microstructure parameters revealed that the crystallite size increases with increasing film thicknesses. The optical measurements on the deposited films were performed in different thicknesseses [ 400 , 450 and 500]nm, to determine the transmission spectrum and the absorption spectra as a function of incident wavelength. The optical absorption coefficient (α) of the films was determined from transmittance spectra in t

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Publication Date
Sun Jan 05 2014
Journal Name
Paripex - Indian Journal Of Research
Effect of heat treatment on the structural and optical properties of CuIn1-xGaxSe thin films
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The structural, optical properties of cupper indium gallium selenite (CuIn1-xGaxSe) have been studied. CuIn1-xGaxSe thin films for x=0.6 have been prepared by thermal evaporation technique, of 2000±20 nm thickness, with rate of deposition 2±0.1 nm/sec, on glass substrate at room temperature. Heat treatment has been carried out in the range (373-773) K for 1 hour. It demonstrated from the XRD method that all the as-deposited and annealed films have polycrystalline structure of multiphase. The optical measurement of the CIGS thin films conformed that they have, direct allowed energy gap equal to 1.7 eV. The values of some important optical parameters of the studied films such as (absorption coefficient, refractive index, extinction coeffici

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Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Study the Effect of thickness on the Optical Properties Performance of active polymeric laser media
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The paper include study the effect thickness of the polymeric sample which is manufactured by thermo press way. The sample was used as an active tunable R6G laser media. The remarks show that, when the thickness of the samples is increased, with the same concentration, the spectrum will shift towards the short wavelength, & the quantum fluorescence yield will increased. The best result we obtained for the quantum fluorescence yield is (0.68) at the sample, with thickness (0.304mm) in Ethanol solvent, while when we used the Pure Water as a solvent, we found that the best quantum fluorescence yield is (0.63) at (0.18mm) thickness of the sample.

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Crossref
Publication Date
Tue Jun 01 2021
Journal Name
Iraqi Journal Of Physics
Structural and optical properties of TiO2:NiO nanoparticles thin films prepare by chemical spray pyrolysis
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The properties of structural and optical of pure and doped nano titanium dioxide (TiO2) films, prepared using chemical spray pyrolysis (CPS) technique, with different nanosize nickel oxide (NiO) concentrations in the range (3-9)wt% have been studied. X-Ray diffraction (XRD) technique where using to analysis the structure properties of the prepared thin films. The results revealed that the structure properties of TiO2 have polycrystalline structure with anatase phase. The parameters, energy gap, extinction coefficient, refractive index, real and imaginary parts were studied using absorbance and transmittance measurements from a computerized ultraviolet visible spectrophotometer (Shimadzu UV-1601 PC) in the wavelength

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Study of the Effect of Berry Paper Mulberry on Optical Properties of Poly Methyl Methacrylate
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In this work, study the optical properties of composites consisting of poly Methyl Methacrylate and Berry Paper Mulberry. The samples of composites were prepared using casting method .The Berry Paper Mulberry (BPM) was added by different concentrations are (0, 2, 4 and 6)wt.%. The optical properties of composites have been studied in the wavelength range (200-800)nm. The absorption coefficient ,energy gap, refractive index, extinction coefficient and dielectric constants have been determined. The results show that the optical constants change with increase of BPM concentrations .

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Publication Date
Tue Dec 11 2018
Journal Name
Iraqi Journal Of Physics
Effect of annealing temperature on structural and optical properties of Cr2O3 thin films by PLD
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In the present work, pulsed laser deposition (PLD) technique was applied to a pellet of Chromium Oxide (99.999% pure) with 2.5 cm diameter and 3 mm thickness at a pressure of 5 Tons using a Hydraulic piston. The films were deposited using Nd: YAG laser λ= (4664) nm at 600 mJ and 400 number of shot on a glass substrate, The thickness of the film was (107 nm). Structural and morphological analysis showed that the films started to crystallize at annealing temperature greater than 400 oC. Absorbance and transmittance spectra were recorded in the wavelength range (300-
4400) nm before and after annealing. The effects of annealing temperature on absorption coefficient, refractive index, extinction coefficient, real and imaginary parts of d

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