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An Active Learning Computer-Based Teaching Tool for Enhancing Students’ Learning and Visualization Skills in Electromagnetics

Mohammed M. Bait-Suwailam Joseph Jervase Hassan Al-Lawati Zia Nadir
International Journal of Electronics and Telecommunications | 2023 | vol. 69 | No 1 | 53-60 | DOI: 10.24425/ijet.2023.144331
Keywords Computer aided tool e-learning electromagnetics engineering education interactive learning PDE tool
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Abstract

Electromagnetic theoretical concepts, which are represented mathematically, are usually challenging to grasp by students. In this study, we explore an interactive technology-based teaching tool to develop further students’ mastery of electromagnetic concepts through learning development and visualization of electromagnetic problems. This visualization of the problems will help students analyse, evaluate, and draw conclusions of the impact of electromagnetic-related problems in real-life. The simulation tool in this study is based on a MATLAB® toolbox package, in which partial-differential equations (PDE) solver is the core engine. In this paper, we will also provide a step-by-step guide on the use of such an interactive computer-aided tool so that it can be a great self-guide tool for beginners in the field of physics and a first-level introductory course in electromagnetism. This study will focus mainly on one classical electrostatic problem that is a challenge to students to visualize, analyze and evaluate. Based on students feedback by the end of the course, 80% of students’ population are more comfortable with the introduced interactive learning tool.
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Authors and Affiliations

Mohammed M. Bait-Suwailam
1 2
Joseph Jervase
1
Hassan Al-Lawati
1
Zia Nadir
1
  1. Department of Electrical and Computer Engineering, Sultan Qaboos University, Muscat, Oman
  2. Remote Sensing and GIS Research Center, Sultan Qaboos University

PAPR reduction using a combination between precoding and non-linear companding techniques for ACO-OFDM-based VLC systems

Nazmi A. Mohammed Mohamed M. Elnabawy Ashraf A. M. Khalaf
Opto-Electronics Review | 2021 | 29 | 2 | 59-70 | DOI: 10.24425/opelre.2021.135829
Keywords visible light communication light emitting diode peak-to-average power ratio bit error rate
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Abstract

Peak-to-average power ratio reduction techniques for visible light communication broadcasting systems are designed, simulated, and evaluated in this work. The proposed techniques are based on merging non-linear companding techniques with precoding techniques. This work aims to nominate an optimum novel scheme combining the low peak-to-average power ratio with the acceptable bit error rate performance. Asymmetrically clipped optical orthogonal frequency division multiplexing with the low peak-to-average power ratio performance becomes more attractive to real-life visible light communication applications due to non-linearity elimination. The proposed schemes are compared and an optimum choice is nominated. Comparing the presented work and related literature reviews for peak-to-average power ratio reduction techniques are held to ensure the proposed schemes validity and effectiveness.
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Bibliography

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Authors and Affiliations

Nazmi A. Mohammed
1
Mohamed M. Elnabawy
2 3
Ashraf A. M. Khalaf
2
ORCID: ORCID
  1. Photonic Research Lab, Electrical Engineering Department, College of Engineering, Shaqra University, Dawadmi 11961, Kingdom of Saudi Arabia
  2. Electrical Engineering Department, Faculty of Engineering, Minia University, Minia, Egypt, P.O. Box 61111, Minia, Egypt
  3. Electronics and Communication Department, Modern Academy for Engineering and Technology, Maadi 11585, Cairo, Egypt

Throughput, Spectral, and Energy Efficiency of 5G Massive MIMO Applications Using Different Linear Precoding Schemes

Ibrahim Salah Kamel Hussein Rahouma Aziza I. Hussein Mohamed M. Mabrook
International Journal of Electronics and Telecommunications | 2023 | vol. 69 | No 1 | 185-191 | DOI: 10.24425/ijet.2023.144349
Keywords throughput massive MIMO spectral efficiency energy efficiency trade off
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Abstract

On fifth-generation wireless networks, a potential massive MIMO system is used to meet the ever-increasing request for high-traffic data rates, high-resolution streaming media, and cognitive communication. In order to boost the trade-off between energy efficiency (EE), spectral efficiency (SE), and throughput in wireless 5G networks, massive MIMO systems are essential. This paper proposes a strategy for EE 5G optimization utilizing massive MIMO technology. The massive MIMO system architecture would enhance the trade-off between throughput and EE at the optimum number of working antennas. Moreover, the EE-SE tradeoff is adjusted for downlink and uplink massive MIMO systems employing linear precoding techniques such as Multiple -Minimum Mean Square Error (M-MMSE), Regularized Zero Forcing (RZF), Zero Forcing (ZF), and Maximum Ratio (MR). Throughput is increased by adding more antennas at the optimum EE, according to the analysis of simulation findings. Next, utilizing M MMSE instead of RZF and ZF, the suggested trading strategy is enhanced and optimized. The results indicate that M-MMSE provides the best tradeoff between EE and throughput at the determined optimal ratio between active antennas and active users equipment’s (UE).
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Authors and Affiliations

Ibrahim Salah
1
Kamel Hussein Rahouma
2 3
Aziza I. Hussein
4
ORCID: ORCID
Mohamed M. Mabrook
5 1
ORCID: ORCID
  1. CCE Department, Faculty of Engineering, Nahda University, Beni-Suef, Egypt
  2. Department of Electrical Engineering, Faculty of Engineering, Minia University, Minia, Egypt
  3. Faculty of Computer Science, Nahda University, Beni-Suef, Egypt
  4. Electrical & Computer Eng. Dept., Effat University, Jeddah, KSA
  5. Faculty of Navigation Science & Space Technology, Beni-Suef University, Beni-Suef, Egypt

Flow characteristics after installation of floating bridge in open channel

Mohamed M. Ibrahim Mahmoud A.R. Eltoukhy Adnan D. Ghanim
Journal of Water and Land Development | 2021 | No 49 | 244-251 | DOI: 10.24425/jwld.2021.137118
Keywords floating bridges flow characteristics flume head loss velocity
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Abstract

A pontoon bridge, also known as a floating bridge, can be used as for pedestrian and vehicle traffic. The buoyancy of the floating bridge limits the maximum load it can carry. This research included experimental runs to study variations of open channel flow characteristics upstream and downstream a floating bridge. Eighty one runs have been carried out using a flume in a hydraulic laboratory. The experimental run program is classified into two main categories; the first investigates the velocity ratios (vds/vus) downstream and upstream the floating bridge. The second category is concerned with the energy head losses (hL) due to the presence of a floating bridge. The experimental runs are carried out using three pontoon lengths, three flow depths, six submerged depths, and three discharges. The results are analysed and graphically presented to help predict hydraulic parameters. The outcomes have shown that the floating bridge upstream, Froude number and submergence of the pontoon are the dominant parameters that affect the studied flow characteristics.
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Authors and Affiliations

Mohamed M. Ibrahim
1
ORCID: ORCID
Mahmoud A.R. Eltoukhy
1
ORCID: ORCID
Adnan D. Ghanim
2
ORCID: ORCID
  1. Benha University, Shoubra Faculty of Engineering, PO Box 11629, Shoubra, Egypt
  2. Advisor to the President of the Iraqi Council of Representatives, Iraq

Assessment of submerged floor water jets to minimize the scour downstream from a stepped spillway

Mohamed M. Ibrahim Al Sayed Ibrahim Diwedar Ahmed Mahmoud Ibraheem
Journal of Water and Land Development | 2021 | No 50 | 122-129 | DOI: 10.24425/jwld.2021.138167
Keywords floor jets flume jet rows stepped spillway scour depth scour length
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Abstract

Because of hydraulic jump, the scour downstream a stepped spillway is the most confusing issue that endangers the overall stability of the spillway. In this paper, thirty-six exploratory runs are described to explore the impact of utilizing submerged water jets fixed in the stilling basin of a stepped spillway on the downstream scour measurements under various flow conditions. A smooth apron where the water jets are disabled is incorporated to characterize the impact of adjustments studied. Trials are performed utilizing different upstream discharges, jets arrangements, and tailwater depths. The results are analyzed and graphically presented. The experimental data are contrasted to a scour formulae developed by other specialists. Outcomes indicated that by utilizing submerged floor water jets, the maximum scour depth is decreased between 14.3 and 36.0%. Additionally, the maximum scour length is reduced by 9.7 to 42.3%. Finally, involving regression analysis, simple formulas are developed to estimate different scour parameters.
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Authors and Affiliations

Mohamed M. Ibrahim
1
ORCID: ORCID
Al Sayed Ibrahim Diwedar
2
ORCID: ORCID
Ahmed Mahmoud Ibraheem
2
ORCID: ORCID
  1. Benha University, Shoubra Faculty of Engineering, PO box 11629 Shoubra, Egypt
  2. National Water Research Center, Hydraulics Research Institute, P.O.Box 74, Shoubra El-Kheima 13411, Egypt

Removal of Cadmium using Alkaline-Treated Activated Carbon from Leucaena Leucocephala Biomass

W.M.H.W. Ibrahim N.S. Sulaiman M.H.M. Amini W.R.A. Kadir M. Mohamed S.F.M. Ramle U. Bilgin W. Rahman
Archives of Metallurgy and Materials | 2022 | vol. 67 | No 3 | 1033-1036 | DOI: 10.24425/amm.2022.139698
Keywords activated carbon cadmium Leucaena leucocephala adsorption
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Abstract

Water contamination that caused by heavy metals is a very common phenomenon in the industrial age. One of the popular way to treat metal contaminated water is by adsorption process using activated carbon as the adsorbent. This paper works on producing activated carbon by chemical means with impregnation ratios of NaOH:char (w/w) was predetermined at 1:1 (ACT1-1), 2:1 (ACT2-1) and 3:1 (ACT3-1) under activation temperature of 700°C. Considering the Leucaena leucocephala is a wildly, easy and fast grown species, with the availability throught the year, it was chosen to be used as the precursor. The properties of these activated carbons and its potential for cadmium removal from aqueus solution was analyzed. It was found that the highest surface area was recorded at 662.76 m²/g. Four parameters were studied which are contact time, the effect of pH, initial concentration of adsorbate and temperature. The equilibrium time was achieved in 40 min treatment at initial concentrations of 30 mg/l. The adsorbent exhibited good sorption potential for cadmium at pH 8.0 and equilibrium temperature of 30℃. Based on the results, this study had proved that activated carbon from Leucaena leucocephala biomass have the good potential to be used for removal of cadmium from wastewater.
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Authors and Affiliations

W.M.H.W. Ibrahim
1
N.S. Sulaiman
2
M.H.M. Amini
1
W.R.A. Kadir
3
M. Mohamed
1
S.F.M. Ramle
1
U. Bilgin
4
W. Rahman
5 6
  1. Universiti Malaysia Kelantan, Faculty of Bioengineering and Technology, Jeli Campus, 17600 Jeli, Kelantan, Malaysia
  2. Universiti Sains Malaysia, School of Industrial Technology, 11800 Minden, Penang, Malaysia
  3. Forest Research Institute Malaysia, 52109 Kuala Lumpur, Selangor, Malaysia
  4. Karadeniz Technical University, Faculty of Forestry, 61080 Trabzon, Turkey
  5. Universiti Malaysia Perlis, Faculty of Mechanical Engineering Technology, Perlis, Malaysia
  6. Universiti Malaysia Perlis, Center of Excellence Geopolymer and Green Technology (CEGeoGTech), Perlis, Malaysia

A complexity efficient PAPR reduction scheme for FBMC-based VLC systems

Radwa A. Roshdy Aziza I. Hussein Mohamed M. Mabrook Mohammed A. Salem
Opto-Electronics Review | 2023 | 31 | 1 | e144919 | DOI: 10.24425/opelre.2023.144919
Keywords visible light communication filter bank multicarrier peak-to-average power ratio reduction computational complexity cube satellite communication link inter-satellite communications
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Abstract

Visible light communication based on a filter bank multicarrier holds enormous promise for optical wireless communication systems, due to its high-speed and unlicensed spectrum. Moreover, visible light communication techniques greatly impact communication links for small satellites like cube satellites, and pico/nano satellites, in addition to inter-satellite communications between different satellite types in different orbits. However, the transmitted visible signal via the filter bank multicarrier has a high amount of peak-to-average power ratio, which results in severe distortion for a light emitting diode output. In this work, a scheme for enhancing the peak-to-average power ratio reduction amount is proposed. First, an algorithm based on generating two candidates signals with different peak-to-average power ratio is suggested. The signal with the lowest ratio is selected and transmitted. Second, an alternate direct current-biased approach, which is referred to as the addition reversed method, is put forth to transform transmitted signal bipolar values into actual unipolar ones. The performance is assessed through a cumulative distribution function of peak-to-average power ratio, bit error rate, power spectral density, and computational complexity. The simulation results show that, compared to other schemes in literature, the proposed scheme attains a great peak-to-average power ratio reduction and improves the bit the error rate performance with minimum complexity overhead. The proposed approach achieved about 5 dB reduction amount compared to companding technique, 5.5 dB compared to discrete cosine transform precoding, and 8 dB compared to conventional direct current bias of an optical filter bank multicarrier. Thus, the proposed scheme reduces the complexity overhead by 15.7% and 55.55% over discrete cosine transform and companding techniques, respectively.
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Authors and Affiliations

Radwa A. Roshdy
1
ORCID: ORCID
Aziza I. Hussein
2
ORCID: ORCID
Mohamed M. Mabrook
3 4
ORCID: ORCID
Mohammed A. Salem
ORCID: ORCID
  1. Department of Electrical Engineering, Higher Technological Institute, 10th of Ramadan City, Egypt
  2. Electrical & Computer Eng. Dept., Effat University, Jeddah, Saudi Arabia
  3. Space Communication Dept., Faculty of Navigation Science & Space Technology, Beni-Suef University, Beni-Suef, Egypt
  4. Department of Communication and Computer Engineering, Faculty of Engineering, Nahda University in Beni-Suef, Egypt

Optimization on friction and wear behaviour of Al-Si alloy reinforced with B4C particles by Powder Metallurgy using Taguchi design

R. Jeya Raj W.A Lenin Anselm M. Jinnah Sheik Mohamed S. Christopher Ezhil Singh T.D John D. Rajeev G. Glan Devadhas K.G. Jaya Christyan R. Malkiya Rasalin Prince R.B. Jeen Robert
Bulletin of the Polish Academy of Sciences Technical Sciences | 2020 | 68 | No. 6 | 1393-1402 | DOI: 10.24425/bpasts.2020.135379
Keywords Al-Si B₄C ANOVA Taguchi design CoF and wear loss
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Abstract

This research paper discusses the friction and wear behaviour of Al-12Si alloy reinforced with B4C prepared through Powder Metallurgy (P/M) method by varying the weight percentage of reinforcement (x = 2, 4, 6, 8, and 10) content. The samples were prepared by using die and punch assembly and the lubricant used to eject the sample from the die was molybdenum disulfide. The compaction was done by using a compression testing machine by applying a pressure of 800 MPa. The dry sliding friction and wear behaviour of the sample was conducted on a Pin-on-Disc machine and the experimental values of friction and wear were calibrated. The Taguchi design experiment was done by applying an L25 orthogonal array for 3 factors at 5 levels for the response parameter Coefficient of Friction (CoF) and wear loss. The SEM images show the shape, size and EDX confirm the existence of Al, Si, B4C particles in the composites. Analysis of Variance (ANOVA) for CoF of S/N ratio, shows that the reinforcement having 34.92% influence towards the S/N ratio of CoF, ANOVA for wear loss of S/N ratio shows that the sliding distance having 46.76% influence towards the S/N ratio of wear loss, when compared to that of the other two input parameters. The interaction line plot and the 2Dsurface plot for CoF and wear loss show that the increase in B4C content decreases the wear loss and CoF. The worn surface shows that the B4C addition will increase the wear resistance.

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Authors and Affiliations

R. Jeya Raj
W.A Lenin Anselm
M. Jinnah Sheik Mohamed
S. Christopher Ezhil Singh
T.D John
D. Rajeev
G. Glan Devadhas
K.G. Jaya Christyan
R. Malkiya Rasalin Prince
R.B. Jeen Robert

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