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 …
The effects of BaCl2 dopant on the optical properties of poly (vinyl alcohol) have been investigated. Pure and BaCl2 doped PVA films were prepared using solvent casting method. These films were characterized using UV/VIS technique in order to estimate the kind of transition which was found to be indirect transition. The value of the optical energy gap was decrease with increasing dopant concentration.
Refractive index, extinction coefficient and Urbach tail have been also investigated; it was found that all the above parameters affects by doping.
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.
Optical Mark Recognition (OMR) is an important technology for applications that require speedy, high-accuracy processing of a huge volume of hand-filled forms. The aim of this technology is to reduce manual work, human effort, high accuracy in assessment, and minimize time for evaluation answer sheets. This paper proposed OMR by using Modify Bidirectional Associative Memory (MBAM), MBAM has two phases (learning and analysis phases), it will learn on the answer sheets that contain the correct answers by giving its own code that represents the number of correct answers, then detection marks from answer sheets by using analysis phase. This proposal will be able to detect no selection or select more than one choice, in addition, using M
... Show MoreOptical Mark Recognition (OMR) is an important technology for applications that require speedy, high-accuracy processing of a huge volume of hand-filled forms. The aim of this technology is to reduce manual work, human effort, high accuracy in assessment, and minimize time for evaluation answer sheets. This paper proposed OMR by using Modify Bidirectional Associative Memory (MBAM), MBAM has two phases (learning and analysis phases), it will learn on the answer sheets that contain the correct answers by giving its own code that represents the number of correct answers, then detection marks from answer sheets by using analysis phase. This proposal will be able to detect no selection or select more than one choice, in addition, using M
... Show MoreThis research explores the use of solid polymer electrolytes (SPEs) as a conductive medium for sodium ions in sodium‐ion batteries, presenting a possible alternative to traditional lithium‐ion battery technology. The researchers prepare SPEs with varying molecular weight ratios of polyacrylonitrile (PAN) and sodium tetrafluoroborate (NaBF4) using a solution casting method with dimethyl formamide as the solvent. Through optical absorbance measurements, we identified the PAN:NaBF4 (80:20) SPE composition as having the lowest energy band gap value (4.48 eV). This composition also exhibits high thermal stability based on thermogravimetric analysis results. Electrochemical impedance spectroscopy re
... Show MoreBlends of polyvinyl pyrrolidone (PVP) and polyvinyl alcohol (PVA) in equal weight ratios (50 wt.% PVP + 50 wt.% PVA) were doped with 15% of various lithium salts (Li2CO3, LiNO3, Li2SO4H2O, and LiCl) and prepared using the solution-casting method, with dimethylformamide (DMF) as the solvent. The impact of these salts on the blends was analyzed and the results showed that the energy gap was decreased by adding lithium salts Li2CO3, LiNO3 and Li2SO4.H₂O. The minimum energy gap value was 3.5 eV obtained from PVP/PVA:15% Li2CO3. The optical constants were determined in the range of 300-1100 nm. The results showed that all the optical constants for doped blends were grown with the addition of lithium salts. The FTIR study confirms the c
... Show MoreIn the current endeavor, a new Schiff base of 14,15,34,35-tetrahydro-11H,31H-4,8-diaza-1,3(3,4)-ditriazola-2,6(1,4)-dibenzenacyclooctaphane-4,7-dien-15,35-dithione was synthesized. The new symmetrical Schiff base (Q) was employed as a ligand to produce new complexes comprising Co(II), Ni(II), Cu(II), Pd(II), and Pt(II) metal-ions at a ratio of 2:1 (Metal:ligand). There have been new ligands and their complexes validated by (FTIR), (UV-visible), 1H-NMR, 13C-NMR, CHNS, and FAA spectroscopy, Thermogravimetric analysis (TG), Molar conductivity, and Magnetic susceptibility. The photostabilization technique to enhance the polymer was also used. The ligand Q and its complexes were mixed in 0.5% w/w of polyvinyl chloride in tetrahydrofuran
... Show Moreيتعرض قانون الموازنة العامة الاتحادية للطعن بعدم الدستورية كغيره من القوانين، بل أن الطعن فيه يكاد يكون سنوياً حال نشره في الجريدة الرسمية ، وتوجه إليه المطاعن بعدم الدستورية إما عن إجراءات تشريعه أو لمضامينه المتعارضة مع الدستور نصاً أو روحاً ، ولكنّه إذا كانت مدة الطعن بعدم دستورية القوانين كافة متاحة دون قيد زمني محدد ولا تتطلب سوى إجراءات إقامة الدعوى العامة وأخصها قيام شرط المصلحة في حالة الدعوى ال
... Show MoreAcademic boredom is one of the most emotional problems that arouse an individual's fatigueness and lowers his interest. This is because of the environment's low efficiency and of spending long monotonous time. This state is characterized by having lack of interest, difficulties in concentration, and the desire to leave the class. It is considered one of the most prominent forms of boredom widespread among students and the most severe and dangerous one that has negative effects and severe psychological and social problems. The current research aims to investigate a randomly selected sample of 335 students from the first and third grades at the directorates of education (Karkh and Rusafa) who suffers from academic boredom. Similarily
... Show MoreThe purpose of this research shed light on the analysis of the relationship between training needs and organizational commitment and the role of a variable contract psychological, and start search of a dilemma thought provoking fundamental questions revolve around the search was the answer to all those questions of tricks theoretical framework to the variables of research first and test models of the relationship and impact secondly During six hypotheses major, The objective of the research the impact of the factors that affect training needs in organizational commitment center the psychological contract, and applied research on a sample of 100 individuals working in the engineering department and maintenance at the D
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