UniMAP RIS :: Browsing Publications 2024 by Department "Universiti Malaysia Perlis"

Publication

A 46% PAE, 2.4-GHz Two-Stage Class E Power Amplifier Utilizing CMOS 0.13-µm Technology

( 2024-01-01)

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A wireless device with a long battery life and great sensitivity becomes difficult to develop since there is a huge demand for low-power, low-cost wireless gadgets. The power amplifier (PA) is the most crucial part of radio frequency (RF) transceivers because of its massive power consumption. Consequently, in order to minimize power loss, a very effective and low-power consumption PA is needed. In this paper, high efficiency two-stage CMOS PA designed in 0.13-μm process for 2.4 GHz IoT transmitter applications is presented. The driver stage and power stage are the two stages that make up the two-stage topology of the proposed CMOS PA. To attain high efficiency and great power gain, a class E PA is used at the power stage. The LC matching network at the output is used for harmonic rejection filter at 2.4 GHz with an additional parallel capacitor helps for better harmonic rejection. In addition, a layout has been successfully designed and optimized. All the components in the proposed PA are designed on-chip. The pre-layout and post-layout simulations have been conducted to verify the proposed PA's performance. The pre-layout simulation of the proposed PA can deliver 19.19 dBm output power and 45.2% PAE at 2.0 V power supply into a 50-Ω load. On the other hand, the proposed PA produced an output power of 17.33 dBm and 46% PAE, according to the results of the post-layout simulation with a similar power supply of 2.0 V. The chip area for the proposed layout design is 1.05 mm2.

3 26

Publication

A compound reconfigurable electronically switched parasitic monopole antenna for sub 6 GHz wireless and vehicular applications

( 2024-05-01)

Ganesh M.

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Raghava N.S.

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Thennarasan Sabapathy

;

Sharma Y.

In this paper, a compound reconfigurable electronically switched parasitic monopole antenna is reported for sub-6 GHz (n77/n78 bands) wireless standards and vehicular communication. The antenna comprises a half-hexagonal-shaped radiating element and two inverted L-shaped parasitic stubs. These stubs are connected through two PIN diodes, allowing for control over frequency. An additional pair of PIN diodes incorporates analogous parasitic stubs into the ground plane to facilitate pattern tilting and polarization. By switching these PIN diodes across seven operating states (OS), the antenna structure could resonate in a single band, spanning 4.5–5.8 GHz (sub-6 GHz higher band), with an omnidirectional pattern specific to OS1. In OS2 and OS3, the antenna resonates in a single band within the range of 4.1–5.7 GHz, featuring beam tilting with linear polarization. In OS4 and OS5, the structure has two bands: one covers 3.3–4.2 GHz (5G-n77 band) with linear polarization, and the other covers 5.1–6.1 GHz (5G WLAN band) with right-hand circular polarization (RHCP) in OS5 and left-hand circular polarization (LHCP) in OS4 with an axial ratio bandwidth of 14.5 %, including pattern tilting within the range of ± 340. Finally, in the OS6 and OS7 structure introduce dual bands of 3.3–3.8 GHz (5G–n78 band) and 4.8–5.8 GHz (sub-6 GHz higher band). Both bands feature LHCP/RHCP with an axial ratio bandwidth of 8.57 % for the lower resonant band and 7.4 % for the higher resonant band. Additionally, it incorporates radiation pattern reconfiguration capabilities. The structure is printed on an FR-4 substrate and measures various associated parameters. The experimental results closely match the simulated results.

15 1

Publication

A Device-to-Device (D2D) Communication between Mobile Robots using Wireless Communication Protocol in Dynamic Environments

( 2024-03-11)

Sarhan M.A.H.

;

Hashim M.S.M.

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Abdul Halim Ismail

;

Mohd Nasir Ayob

;

Hassrizal Hassan Basri

;

Muhamad Safwan Muhamad Azmi

;

Othman S.M.

;

Kanafiah S.N.A.M.

;

Muhamad Khairul Ali Hassan

Mobile robots must have the ability to guarantee safety for operation in a dynamic environment and close to other moving objects. There are many research had been conducted to make the robot safer by utilizing sensors and big data technology to make the mobile robot able to navigate autonomously and intelligently. One of the key elements in autonomous robots is communication between robots. In this paper, device-to-device (D2D) technology has been used to develop communication between robots. To establish the algorithm for D2D communications, radio frequency (RF) used as communication protocols that can perform D2D communication in real-time applications. The performance of D2D communication was then be assessed in terms of distance and latency. RF transceiver module has been mounted on the robot with Arduino to allow communication between mobile robot to other mobile robots in order to transfer data from robot's sensors to the other mobile robots. By utilizing the gathered information and data, the robot can assess its surroundings and predict the movement of other robots to avoid collisions between robots. The results show that the RF transceiver module is capable to send and receive data between two robots with latency up to 4.865s. It is envisaged that the proposed module can be very useful for developing D2D communication between robots to operate in dynamic environments.

58 8

Publication

A DFT study of the optoelectronic properties of B and Be-doped Graphene

( 2024-02-01)

Agbolade L.O.

;

Dafhalla A.K.Y.

;

Zayan D.M.I.

;

Tijjani Adam

;

Abdullah Chik

;

Adewale A.A.

;

Subash Chandra Bose Gopinath

;

Uda Hashim

The electronic and optical properties of Boron (B) and Beryllium (Be)-doped graphene were determined using the ab initio approach based on the generalized gradient approximations within the Full potential linearized Augmented Plane wave formalism (FP-LAPW). Our findings demonstrated that doping at the edges of graphene is notably stable. In both systems, Be- doped graphene proves more efficient in manipulating the band gap of graphene. Both B and Be, induce P-type doping in graphene. B-doped graphene exhibits a negligible magnetic moment of 0.000742, suggesting its suitability for catalytic semiconductor devices. Conversely, Be-doped graphene displays a large magnetic moment of 1.045 μB, indicating its potential in spintronics. Additionally, this study elucidates the influence of the dopant atoms on the optical properties of graphene. These findings underscore a stable and controllable method for modelling graphene at its edges with B and Be atoms, opening new avenues in the design of these devices.

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Publication

A Fully-Bioresorbable Nanostructured Molybdenum Oxide-Based Electrode for Continuous Multi-Analyte Electrochemical Sensing

( 2024-01-01)

Fernandes C.

;

Franceschini F.

;

Smets J.

;

Deschaume O.

;

Nurul Izni Rusli

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Bartic C.

;

Ameloot R.

;

Baert K.

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Ustarroz J.

;

Taurino I.

Bioresorbable electrochemical sensors remain mostly unexplored despite their ability to provide continuous in situ measurements of critical biomarkers. The primary challenge arises from the direct exposure of the electrodes’ thin metal films to biofluids, which poses difficulties in ensuring both proper operational lifetimes and sensing performance. Molybdenum (Mo) presents itself as a promising biometal due to its uniquely gradual dissolution in biofluids, facilitated by the formation of a slower-dissolving MoOx surface layer. Consequently, carefully engineered MoOx films can endow transient electrochemical sensors with unparalleled stability during extended operational lifetimes. Herein an unprecedented sensor architecture achieved via the unique pairing of sputtered Mo and MoOx thin films, probed as a pH and dissolved oxygen sensor is reported. Compared to a bare Mo electrode, a bilayer Mo+MoOx electrode subjected to post-deposition annealing (400 °C, 60 min, N2 environment) displayed a largely improved stability (>24 h) in solution and demonstrated predictable functionality during ongoing film dissolution at 37 °C. Collectively, this work establishes a pioneering strategy for the fabrication of reliable and clinically relevant implantable electrochemical sensors.

1 21

Publication

A low profile circularly polarized metasurface-based ultra-wideband 4x4 MIMO antenna for 5G NR band FR2 frequencies

( 2024-05-01)

Angadi S.

;

Sharma Y.

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Raghava N.S.

;

Thennarasan Sabapathy

This article presents a polarization conversion metasurface-based low-profile ultra-wideband circularly polarized (CP) multiple-input multiple-output (MIMO) antenna with high performance that is specifically designed for operating in 5G New Radio (NR) bands in frequency range 2 (FR2). For these frequency bands, the 4-port MIMO antenna is being proposed for the first time and is capable of being operated in all of the newly created radio frequency bands in the 5G FR2 region. The main advantage of the proposed configuration is that it requires no isolation/decoupling circuit and the antenna elements are placed orthogonal to their adjacent elements. The 4x4 MIMO antenna offers a good impedance bandwidth of 111.09 % ranging from (12.87–45.02) GHz below − 10 dB reflection coefficient with a minimum isolation of –23.77 dB and maximum isolation of −52.53 dB. The maximum peak realized gain of the 4x4 MIMO antenna without metasurface is 8.14 dBi in the operating band. An improvement of 47 % in the peak realized gain was observed after stacking the metasurface on top of the radiating patch. The proposed antenna produces a circular polarization (CP) in the desired operating band. The 3-dB axial ratio impedance bandwidth for the lower band in millimeter wave (mm-Wave) is 14.13 % ranging from (23.22 – 26.75 GHz) and for the upper band is 7.92 % ranging from (40.82 – 44.19 GHz). Initially, the proposed antenna is designed for a single element and it is extended for a 4-element MIMO with added 4x4 metasurface unit cells for improvement of gain and polarization conversion. The simulated and measured results are in good agreement. In addition to that, the envelope correlation coefficient (ECC), channel capacity loss (CCL), total active reflection coefficient (TARC), mean effective gain (MEG), and diversity gain (DG) are calculated and simulated for the proposed four-element MIMO antenna. The designed metsurface-based circularly polarized MIMO antenna covers all 5G new radio frequency bands in FR2 and hence the designed antenna is applicable for 5G NR band FR2 in mm-Wave communications.

28 1

Publication

A metasurface based close-proximity two-port circularly polarized MIMO antenna for mid-band sub-6 GHz 5G applications

( 2024-08-01)

Angadi S.

;

Sharma Y.

;

Raghava N.S.

;

Thennarasan Sabapathy

This work presents a compact dual-band two-port multiple input multiple output (MIMO) antenna with high performance that is specifically used for 5G applications. The proposed design comprises closely spaced, mirror-symmetrical X-shaped structures positioned at an edge spacing of 0.02 λ0 between antenna elements. Subsequently, a metasurface is located at a distance of 0.27 λ0 above the radiator to improve the performance of the MIMO antenna. The proposed antenna resonates at 3.27 GHz within a frequency range of (3.03–3.44) GHz in the primary band, achieving a peak realized gain of 7.57 dBi. In the secondary band, the resonance occurs at 4.78 GHz with a range of (4.01–5.87) GHz below −10 dB reflection coefficient and produces a peak realized gain of 5.60 dBi. After positioning the metasurface on top of the reference antenna, the peak realized gain improves by 116.28 % in the primary band and 69.69 % in the secondary band respectively. Whereas the isolation is increased to −30.01 dB from –22.26 dB in the primary band, similarly for the secondary band the isolation is amended to −21.00 dB from −18.20 dB. Moreover, circular polarization is realized at working frequencies after placing the metasurface on the reference antenna. Simulation and measurement results prove that the S-parameters exceed more than −20 dB in both frequency bands. Additionally, MIMO performance metrics, including envelope correlation coefficient (ECC), channel capacity loss (CCL), total active reflection coefficient (TARC), mean effective gain (MEG), and diversity gain (DG) are simulated and measured. The designed antenna proves suitable for the new radio (NR) 5G of n48 (3.55–3.70 GHz) in the primary band and the n79 (4.4–5.0 GHz) in the secondary band respectively.

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Publication

A new class of two-dimensional (2-D) modified-FCC (M-FCC) OCDMA for cardinality enrichment towards 6G network accessibility

( 2024-01-31)

Dayang H.

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Mohd Rashidi Che Beson

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Syed Alwee Aljunid Syed Junid

In this paper, we introduce a new two-dimensional (2-D) wavelength/time optical code division multiple access (OCDMA) known as 2D Modified-Flexible Cross Correlation (M-FCC) code. The 2-D M-FCC code is developed from the one-dimensional flexible cross correlation code families with flexibility in-phase cross-correlation at any given number of users and weights. The main goal is to reduce noise as well as multiple-access interference (MAI) at the same time to accommodate higher cardinality with minimum noise. The increment of cardinality is to be engaged towards 6G network accessibility. From the numerical results, it indicated good performance whereas the 2-D M-FCC code at bit rate 622 Mbps with at BER of 3.49 ×10-28, can accommodate 200 number of cardinalities enrichment. Moreover, the 2-D M-FCC code shows good SNR curves as gradually decreases as the number of users increases at different bit rate 155 Mbps, 622 Mbps, 1.1 Gbps and 2.5 Gbps, respectively.

6 27

Publication

A Preliminary Investigation on The Correlation Between the Arrival Time of Ultrasonic Signals and The Concrete Condition

( 2024-01-01)

Mohamad F.A.J.

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AA. Ahmad

;

Rahim R.A.

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Ibrahim S.

;

Jamaludin J.

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Ahmad N.

;

Yunus F.R.M.

;

Mohd Hafiz Fazalul Rahiman

;

Zaini N.A.H.S.

Concrete is a composite material that is widely used in a construction project. The evaluation of concrete structure is very important in order to determine its strength and quality. Concrete is commonly evaluated by using the ultrasonic pulse velocity (UPV) method, which adopted the concept of measuring time of a first arrival of the received signal. Hence, this paper aims to evaluate the first arrival time of the detected ultrasonic signals based on different conditions of concrete structure. A simulation study was conducted by using COMSOL Multiphysics software version 5.6. Data collected were categorized into three sections, including in concrete model with inclusion of air hole, crack, and rust. From the simulation results, concrete models with inclusion of air hole showed an increment in the arrival time as the size of air hole increase. For the concrete models with rust, the arrival time were significantly increased in 20-mm and 40-mm rust, however it turns down as the size of rust reached 60-mm. The results also indicated that transverse crack took a longer arrival time compared to other orientation of crack.

Publication

A review of industry 4.0 development progress in Indonesia

( 2024-03-07)

Mursadi R.A.

;

Tan Chan Sin

;

Ramli M.F.

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Ahmad Humaizi Hilmi

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Rosmaini Ahmad

;

Azmi H.

Rapid advancements in digital technology have resulted in a new industrial revolution phenomenon known as Industry 4.0. This revolution introduces modern technologies that enable the connectivity of all components within industries. This paper reviews the current status and progress in Indonesia heading to Industry 4.0. The Indonesia' government has been launched 'Making Indonesia 4.0's' roadmap in 2018 including the five priority industrial sectors namely food and beverages, chemicals, textile, automotive, and electronics and ten national priorities. Indonesia which is currently only in the stage of entering the industrial era 4.0 with few of challenges and opportunities by following the roadmap of "Making Indonesia 4.0".

28 6

Publication

A Review of Learner’s Model for Programming in Teaching and Learning

( 2024-02-01)

Hanafi H.F.

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Selamat A.Z.

;

Ghani M.M.

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Wan Azani Wan Mustafa

;

Harun M.F.

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Naning F.H.

;

Huda M.

;

Alkhayyat A.

Over recent years, computer science (CS) teachers and instructors have faced several challenges in helping students strengthen their understanding of programming. The existing assessment methods could be more effective in assessing students' programming skills and knowledge, thus requiring a review of issues surrounding the instruction of programming courses. Against this backdrop, the authors systematically reviewed the current literature to identify several socio-cognitive factors that can help develop a learner model for learning programming. Specifically, the Systematic Reviews and Meta-Analyses (PRISMA) technique was utilized to identify and select relevant articles from three primary online databases: Scopus, Web of Science, and Eric. Initially, 401 relevant papers were identified and retrieved, further reduced to only 24 articles based on specific selection criteria. As revealed, several demographic factors (such as gender, age, ethnicity, and socioeconomic status) and socio-cognitive factors (motivation, attitude, and interest) have been shown to impact student learning of programming significantly. The authors' findings from the systematic literature review helped synthesize the essential elements of the learner model that must be carefully considered and utilized. Arguably, the use of such a new learner model can compel instructors to teach programming more effectively by clarifying several students' socio-cognitive backgrounds, which collectively have a significant impact on student learning of programming courses or subjects at the primary, secondary, and tertiary levels of education, especially in the Malaysian educational context.

1 24

Publication

A Review on Graphene Analytical Sensors for Biomarker-based Detection of Cancer

( 2024-01-01)

Subash Chandra Bose Gopinath

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Ramanathan S.

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More M.

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Patil K.

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Patil S.J.

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Patil N.

;

Mahajan M.

;

Madhavi V.

The engineering of nanoscale materials has broadened the scope of nanotech-nology in a restricted functional system. Today, significant priority is given to immediate health diagnosis and monitoring tools for point-of-care testing and patient care. Graphene, as a one-atom carbon compound, has the potential to detect cancer biomarkers and its derivatives. The atom-wide graphene layer specialises in physicochemical characteristics, such as improved electrical and thermal conductivity, optical transparency, and increased chemical and mechanical strength, thus making it the best material for cancer biomarker detection. The outstanding mechanical, electrical, electrochemical, and optical properties of two-dimensional graphene can fulfil the scientific goal of any biosensor development, which is to develop a more compact and portable point-of-care device for quick and early cancer diagnosis. The bio-functionalisation of recognised biomarkers can be improved by oxygenated graphene layers and their composites. The significance of graphene that gleans its missing data for its high expertise to be evaluated, including the variety in surface modification and analytical reports. This review provides critical insights into graphene to inspire research that would address the current and remaining hurdles in cancer diagnosis.

19 7

Publication

A Review on Picture Fuzzy Aggregation Operators

( 2024-12-01)

Siti Rohana Goh Abdullah

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Muhammad Zaini Ahmad

Multiple Attribute Decision Making (MADM) is a fundamental concept in the scope of the decision sciences, serving as a structured method for evaluating and selecting the most appropriate alternative option from a pool of available alternatives. MADM methods have gained prominence over the years and are frequently applied in realworld scenarios. Nevertheless, decision-making in practical situations often involves information that is imprecise and uncertain, especially conflicting criteria or attributes. Therefore, Picture Fuzzy Sets (PFSs) and Aggregation Operators (AOs) have proven invaluable in effectively addressing decision challenges characterized by impression and uncertainty. During the past few years, various Picture Fuzzy Aggregation Operators (PFAOs) have been suggested and established but have not been thoroughly reviewed. The primary highlight of this research is to analyse as well as review the development and proposals surrounding PFAOs and their diverse applications within the decision-making paradigm. Regarding this, a review of 140 published articles from 2017 to 2022 appeared in 48 high-ranking journals cited from the "Scopus" and "Web of Science" databases. Other than that, all these articles have been classified by the nationalities of authors, publication year, published journal, research area, operators and methods. The findings of this study discovered that PFAOs have been increasingly applied for supporting decisions due to their frequent implications and applications in different managerial domains, either profit or non-profit organizations. This literature survey's significant contribution provides a platform for researchers to identify future dimensions of works as improvements for decision-making in picture fuzzy environments while also promoting future application of the approaches.

5

Publication

A Review on the Concrete Durability Exposed to Different Wet-Dry Cycles Conditions

( 2024-04-19)

Zarina Yahya

;

Rafiza Abd Razak

;

Khairunnisa Muhamad

Concrete structure is prone to corrosion and weathering when built near marine environment. The greater damage on the concrete can be observed when it involves wet-dry action such as tidal waves combine with the existence of aggressive ions such as sulphate and chloride in seawater. The objective of this study is to review on the mechanism of sulphate, chloride attack toward concrete, parameters that influence the wet-dry action and identify the overview of research trends. The mechanism of sulphate and chloride attack during wet-dry action had reciprocal inhibiting effect on concrete and the penetration level for each ion also vary. The physical and mechanical damage of concrete exposed to wet-dry action also influence by wet-dry ratio, number of cycles and temperature during drying process. The main compound detected during exposure period are Friedel salt, ettringite, mirabilite and thenardite which can cause concrete delamination and spalling.

Publication

A review: Outdoor visible light communication on modulation and receiver denoising scheme

( 2024-02-08)

Othman N.

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Mohd Rashidi Che Beson

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Syed Alwee Aljunid Syed Junid

;

Rosdisham Endut

A rapid growth of wireless communication system has boosted the exponential development on smart technology while driving a substantial increase in traffic volume. With a highly congested and demand on RF bandwidth spectrum, Visible Light Communication (VLC) seem as a complementary technology towards RF based system which provide wider bandwidth, free and unregulated channel, poses no health hazard, high security and low power consumption leads VLC to be one of the promising technology in data transmission. By maintaining the main purpose of illumination, the exploitation on the existing LED-based lighting system is used as a transmission mechanism to photodetector or image sensor which is used to detect the variations of the light intensity via free space optical channels. Different VLC modulation schemes is review in this paper to see the pros and cons of each scheme implemented in outdoor application specifically for vehicle-to-vehicle (V2V) VLC system. Various type of noises is presented in this paper with the denoising scheme to eliminate or reduce the shot and thermal noise caused by natural sunlight and artificial roadside infrastructure light which degrades the performance of VLC system.

Publication

A study of liquid-liquid extraction system performance to remove lead from aqueous solution

( 2024-03-07)

Ibrahim N.H.

;

Siti Nazrah Zailani

;

Noor Ainee Zainol

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Subash Chandra Bose Gopinath

;

Muhammad Nur Aiman Uda

Lead (Pb) is one of the top-heavy metal pollutants often encountered in industrial wastewater. The presence of high levels of Pb in the environment may cause long-term health risks to humans. This study was focused on the removal and stripping of lead solution using liquid-liquid extraction (LLE) process. LLE was conducted using three types of extractants with sulphuric acid, H2SO4 as a stripping agent. Experimental parameters studied were types of extractant bis(2-ethylhexyl) phosphate (D2EHPA), trioctylamine (TOA) and tributylphosphate (TBP) and concentration of extractant (0.005, 0.05 and 0.5 M) and types of diluents (kerosene and toluene) respectively. The result indicates that, D2EHPA shows a good performance for removal of Pb compared to TOA and TBP where the highest extraction rate of lead was 93.92 %. Meanwhile, TBP shows the highest stripping rate of lead which is 93.57 %. Kerosene was found to be the best diluent compared to toluene. Overall, the optimum Pb extraction and stripping was obtained at 0.5 M D2EHPA and 0.005 M TBP with 250 rpm stirring speed, 5 min stirring time, 0.5 M H2SO4 and treat ratio 1:1. This LLE process has a good potential to aid in low-cost and environmentally friendly.

Publication

A Three-Level Factorial Model for Maximising Protein Extraction from Rice Bran with Choline Chloride: Glycerol

( 2024-05-01)

Ramlee K.A.F.K.

;

Daud N.M.A.N.

;

Mohd Sharizan Md Sarip

;

Amirul Ridzuan Abu Bakar

;

Zainudin M.A.M.

Rice bran, a by-product of rice milling, contains four protein types – albumin, globulin, prolamin, and glutelin – known for their hypoallergenic nature and nutritional advantages. To enhance rice bran's worth, its protein was isolated using deep eutectic solvent (DES). The influence of three operational factors (temperature, extraction time, and rice bran to DES ratio) on protein yield was evaluated post-conversion using three level factorial design. Optimal conditions at 80°C, 3 hours, and 1:5 rice bran to DES ratio yielded the highest extracted rice bran protein (RBP) at 17.49%. Temperature and solvent-to-sample ratio show the lowest p-value, indicating a significant effect on the RBP yield. The validation test shows an error of less than 5% between the experimental and the predicted value, showing the model can be used to predict the RBP yield. The RBP was then characterised using Fourier Transform Infrared Spectroscopy (FTIR), Bradford Assays and SDS-PAGE electrophoresis to confirm the protein presence in rice bran powder. FTIR analysis showed the existence of amide I, amide II, aliphatic groups and amine or hydroxyl groups in the RBP. Furthermore, Bradford assays analysis indicated 23.89 ± 0.75% protein content in rice bran powder. SDS-PAGE electrophoresis shows the existence of Albumin and globulin in the RBP. In conclusion, a full three level factorial can be used to model and predict the optimal condition for protein extraction from rice bran using ChCl-Gly DES.

35 4

Publication

AC and DC anodization on the electrochemical properties of SS304L: A comparison

( 2024-01-01)

Azmi N.S.

;

Mohd Nazree Derman

;

Zuraidawani Che Daud

This study investigates the application of alternating current (AC) and direct current (DC) anodization techniques on stainless steel 304L (SS304L) in an ethylene glycol and ammonium fluoride (NH4F) electrolyte solution to produce a nano-porous oxide layer. With limited research on AC anodizing of stainless steel, this study focuses on comparing AC and DC anodization in terms of current density versus time response, phase analysis using X-ray diffraction (XRD), and corrosion rate determined by linear polarization. Both AC and DC anodization were performed for 60 minutes at 50 V in an electrolyte solution containing 0.5% NH4F and 3% H2O in ethylene glycol. The results show that AC anodization exhibited higher current density compared to DC anodization. XRD analysis revealed the presence of ferrite (α-Fe) and austenite (γ-Fe) phases in the as-received specimen, while both AC and DC anodized specimens exhibited only the γ-Fe phase. The corrosion rate of the AC-anodized specimen was measured at 0.00083 mm/year, lower than the corrosion rate of the DC-anodized specimen at 0.00197 mm/year. These findings indicate that AC anodization on stainless steel offers advantages in terms of higher current density, phase transformation, and lower corrosion rate compared to DC anodization. These results highlight the need for further investigation and exploration of AC anodization as a promising technique for enhancing the electrochemical properties of stainless steel.

1 31

Publication

Advancements in UAV image semantic segmentation: A comprehensive literature review

( 2024-06-01)

Ahmed S.A.

;

Hazry Desa

;

Easa H.K.

;

Hussain A.S.T.

;

Taha T.A.

;

Salih S.Q.

;

Hasan R.A.

;

Ahmed O.K.

;

Ng P.S.J.

Unmanned Aerial Vehicles (UAVs) have revolutionized data acquisition across various domains, presenting immense potential for image processing and semantic segmentation. This literature review encompasses a thorough exploration of advancements, techniques, challenges, and datasets pertaining to UAV image semantic segmentation. It begins by introducing the fundamental concepts of UAVs, highlighting their pivotal role in capturing high-resolution imagery that serves diverse applications. The integration of deep learning algorithms with UAVs is emphasized, unlocking new horizons in autonomous flight, security, and environmental monitoring. Delving into the core principles of semantic segmentation, the review elucidates the critical task of classifying every pixel in an image. Convolutional Neural Networks (CNNs) are presented as the cornerstone technology, tracing their evolution from traditional CNNs to the highly adaptable Fully Convolutional Networks (FCNs). A substantial portion of the review is dedicated to FCNs, underscoring their ability to process images of varying dimensions while maintaining spatial coherence in the output. Their pivotal role in semantic segmentation, encompassing both classification and localization, is articulated. The subsequent sections delve into a comprehensive survey of state-of-the-art models, including SegNet, PSPNet, DeepLabNet, EfficientNet, DenseNet-C, and LinkNet. Each model's unique strengths and applications contribute to the evolving landscape of semantic segmentation tasks. The versatility of the U-Net architecture takes center stage in the latter parts of the review. Its fundamental structure is elucidated, followed by a comprehensive examination of its manifold adaptations—3D-U-Net, ResU-Net, U-Net++, Adversarial U-Net, Cascaded U-Net, and Improved U-Net 3+. These modifications address intrinsic challenges such as limited receptive fields and class imbalances, propelling U-Net to the forefront of image segmentation techniques. The subsequent sections pivot toward the application of U-Net in UAV image segmentation, illustrating its efficacy in diverse tasks, including land cover and crop classification. Nevertheless, persisting challenges, such as the scarcity of annotated datasets and the need for model generalization across varied environmental conditions, remain key areas of concern. The review culminates by underlining the significance of large, authentic datasets and data augmentation techniques. Furthermore, a brief exploration of publicly available UAV image datasets is presented, enhancing our understanding of the resources accessible for training and evaluating models. This comprehensive literature review encapsulates the dynamism of UAV image processing and semantic segmentation, illuminating recent developments and avenues for future research in this burgeoning field.

2 15

Publication

Advances in nano sensors for monitoring and optimal performance enhancement in photovoltaic cells

( 2024-04-19)

Dhahi T.S.

;

Yousif Dafhalla A.K.

;

Tayfour O.E.

;

Mubarakali A.

;

Alqahtani A.S.

;

Tayfour Ahmed A.E.

;

Elobaid M.E.

;

Tijjani Adam

;

Subash Chandra Bose Gopinath

Nanosensors have gained significant attention in recent years for improving energy conversion and storage performance in solar cells. These nanosensors, typically made from nanoparticles or nanowires, can be embedded within the solar cell to monitor parameters like temperature and light intensity. By monitoring these parameters, nanosensors provide real-time feedback and control to optimize the efficiency and performance of the solar cell. They also play a role in detecting potential issues, such as defects, for proactive maintenance and troubleshooting. The integration of nanosensors in solar cells enables the development of smart energy systems, leading to increased power output, improved stability, and a longer lifespan of solar cells. The deployment of nanosensors in solar cells offer promising trajectory for advancing energy conversion, utilization, and storage capabilities. This review summarizes recent advances in nanosensors in solar cells, with a focus on the role they play in enhancing energy conversion, utilization, and storage performance.

2

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