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Energy management and exchange have increasingly shifted from concentrated to hierarchical modes. Numerous issues have arisen in the decentralized energy sector, including the storage of customer data and the need to ensure data integrity, fairness, and accountability in the transaction phase. The problem is that in the field of the innovative technology of blockchain and its applications, with the energy sector still in the developmental stages, there is still a need for more research to understand the full capacity of the technology in the field. The main aim of this work was to investigate the state of the current research of blockchain technologies as well as their application within the field of energy. This work also set out to identify certain research gaps and provide a set of recommendations for future directions. Among these research gaps is the application of blockchain in decentralized storage, the integration of blockchain with artificial intelligence, and security and privacy concerns, which have not received much attention despite their importance. An analysis of fifty-seven carefully reviewed studies revealed that the emerging blockchain which provides privacy-protection technologies in cryptography and other areas that can be integrated to address users’ privacy concerns is another aspect that needs further investigation. Grid operations, economies, and customers will all learn from blockchain technology as it provides disintermediation, confidentiality, and tamper-proof transfers. Moreover, it provides innovative ways for customers and small solar generators to participate more actively in the electricity sector and to benefit from their properties. Blockchains are a rapidly evolving field of research and growth. A study of this emerging technology is necessary to increase comprehension, to educate the body of expertise on blockchains, and to realize its potential. This study recommends that future work investigates the potential application of blockchain in the energy sector as well as the challenges that face its implementation from the perspective of policy makers. This future approach will enable researchers to direct their focus to the case studies approach, which will facilitate and ease the application of blockchain technology.
Yahia Baashar; Gamal Alkawsi; Ammar Ahmed Alkahtani; Wahidah Hashim; Rina Azlin Razali; Sieh Kiong Tiong. Toward Blockchain Technology in the Energy Environment. Sustainability 2021, 13, 9008 .
AMA StyleYahia Baashar, Gamal Alkawsi, Ammar Ahmed Alkahtani, Wahidah Hashim, Rina Azlin Razali, Sieh Kiong Tiong. Toward Blockchain Technology in the Energy Environment. Sustainability. 2021; 13 (16):9008.
Chicago/Turabian StyleYahia Baashar; Gamal Alkawsi; Ammar Ahmed Alkahtani; Wahidah Hashim; Rina Azlin Razali; Sieh Kiong Tiong. 2021. "Toward Blockchain Technology in the Energy Environment." Sustainability 13, no. 16: 9008.
In the electric power distribution system, power electronics technologies associated with renewable energy systems (RES) and smart grids have gained growing interest. The power electronics devices are used to convert, control, or transfer electric power from RES to the power grids. However, the continuous increase in switching frequencies resulting from these power electronics technologies has led to the emergence of new emissions in the range of 2-150 kHz, outside the classical frequency range for power quality. These emissions are known worldwide as supraharmonics (SH).These emissions negatively affect the power quality of electrical distribution systems and reduce their efficiency and lifetime. Thus, the supraharmonics emissions have been investigated in the literature, and several methods were developed focusing on identifying, measuring, and setting new standards to mitigate the impact of these emissions on the power quality. Although these individual studies have been well documented, a comparative overview of its identifications, current standards, and measurement techniques had not been described so far. Therefore, this study extensively reviews the related techniques and standards for identifying, measuring, and mitigating SH emissions. Moreover, the current research gap in this important field is highlighted, and an illustration on how this problem was tackled in the past few years is presented. Additionally, the SH characteristics alongside with insights into the mitigations and measurements are highlighted and analyzed accordingly. Finally, some important recommendations to mitigate SH emissions are suggested. This review will hopefully strengthen the efforts toward the development of SH domain by providing the necessary groundwork for further mitigations, standards, and measuring techniques improvement.
Saad T. Y. Alfalahi; Ammar Ahmed Alkahtani; Ali Q. Al-Shetwi; Ali Saadon Al-Ogaili; Afaneen A. Abbood; Muhamad Bin Mansor; Yousef Fazea. Supraharmonics in Power Grid: Identification, Standards, and Measurement Techniques. IEEE Access 2021, 9, 103677 -103690.
AMA StyleSaad T. Y. Alfalahi, Ammar Ahmed Alkahtani, Ali Q. Al-Shetwi, Ali Saadon Al-Ogaili, Afaneen A. Abbood, Muhamad Bin Mansor, Yousef Fazea. Supraharmonics in Power Grid: Identification, Standards, and Measurement Techniques. IEEE Access. 2021; 9 (99):103677-103690.
Chicago/Turabian StyleSaad T. Y. Alfalahi; Ammar Ahmed Alkahtani; Ali Q. Al-Shetwi; Ali Saadon Al-Ogaili; Afaneen A. Abbood; Muhamad Bin Mansor; Yousef Fazea. 2021. "Supraharmonics in Power Grid: Identification, Standards, and Measurement Techniques." IEEE Access 9, no. 99: 103677-103690.
The reliability of photovoltaic (PV) modules operating under various weather conditions attracts the manufacturer’s concern since several studies reveal a degradation rate higher than 0.8% per year for the silicon-based technology and reached up to 2.76% per year in a harsh climate. The lifetime of the PV modules is decreased because of numerous degradation modes. Electromigration and delamination are two failure modes that play a significant role in PV modules’ output power losses. The correlations of these two phenomena are not sufficiently explained and understood like other failures such as corrosion and potential-induced degradation. Therefore, in this review, we attempt to elaborate on the correlation and the influence of delamination and electromigration on PV module components such as metallization and organic materials to ensure the reliability of the PV modules. Moreover, the effects, causes, and the sites that tend to face these failures, particularly the silicon solar cells, are explained in detail. Elsewhere, the factors of aging vary as the temperature and humidity change from one country to another. Hence, accelerated tests and the standards used to perform the aging test for PV modules have been covered in this review.
Abdulwahab Hasan; Ammar Ahmed Alkahtani; Seyed Shahahmadi; Mohammad Nur E. Alam; Mohammad Islam; Nowshad Amin. Delamination-and Electromigration-Related Failures in Solar Panels—A Review. Sustainability 2021, 13, 6882 .
AMA StyleAbdulwahab Hasan, Ammar Ahmed Alkahtani, Seyed Shahahmadi, Mohammad Nur E. Alam, Mohammad Islam, Nowshad Amin. Delamination-and Electromigration-Related Failures in Solar Panels—A Review. Sustainability. 2021; 13 (12):6882.
Chicago/Turabian StyleAbdulwahab Hasan; Ammar Ahmed Alkahtani; Seyed Shahahmadi; Mohammad Nur E. Alam; Mohammad Islam; Nowshad Amin. 2021. "Delamination-and Electromigration-Related Failures in Solar Panels—A Review." Sustainability 13, no. 12: 6882.
This study provides a techno-financial evaluation of two sites in Malaysia: Kudat, located on the coast of the northernmost part of Sabah, the state of East Malaysia with promising wind potential, and Putrajaya in the Klang Valley region with moderate wind potential at high elevations similar to the dominant cities in Malaysia. Three small-scale wind turbines were evaluated, taking into account a nominal electrical power generation below 100 kW. The research is focused on 220 residential households. The software used to perform the evaluation was Hybrid Optimization of Multiple Energy Resources (HOMER). The research novelty is the examination of the non-hybrid small-scale turbines at high elevations for regions with low wind speed, such as Malaysia. Regardless of the wind farms’ financial profit, this study used the net present cost (NPC) analysis in all cases. This research demonstrates the feasibility of small-scale wind turbines mounted at high elevations for generating sufficient energy. The results indicate that in both areas, the RX-20KH3 model is the best option, and the costs of the FH-5000 and RX-20KH3 farms are proportionate for a renewable project. Furthermore, with government support, the WES80 farm could be suitable.
Gamal Alkawsi; Yahia Baashar; Ammar Alkahtani; Chin Lim; Sieh Tiong; Mohammad Khudari. Viability Assessment of Small-Scale On-Grid Wind Energy Generator for Households in Malaysia. Energies 2021, 14, 3391 .
AMA StyleGamal Alkawsi, Yahia Baashar, Ammar Alkahtani, Chin Lim, Sieh Tiong, Mohammad Khudari. Viability Assessment of Small-Scale On-Grid Wind Energy Generator for Households in Malaysia. Energies. 2021; 14 (12):3391.
Chicago/Turabian StyleGamal Alkawsi; Yahia Baashar; Ammar Alkahtani; Chin Lim; Sieh Tiong; Mohammad Khudari. 2021. "Viability Assessment of Small-Scale On-Grid Wind Energy Generator for Households in Malaysia." Energies 14, no. 12: 3391.
Anomaly detection has gained considerable attention in the past couple of years. Emerging technologies, such as the Internet of Things (IoT), are known to be among the most critical sources of data streams that produce massive amounts of data continuously from numerous applications. Examining these collected data to detect suspicious events can reduce functional threats and avoid unseen issues that cause downtime in the applications. Due to the dynamic nature of the data stream characteristics, many unresolved problems persist. In the existing literature, methods have been designed and developed to evaluate certain anomalous behaviors in IoT data stream sources. However, there is a lack of comprehensive studies that discuss all the aspects of IoT data processing. Thus, this paper attempts to fill this gap by providing a complete image of various state-of-the-art techniques on the major problems and core challenges in IoT data. The nature of data, anomaly types, learning mode, window model, datasets, and evaluation criteria are also presented. Research challenges related to data evolving, feature-evolving, windowing, ensemble approaches, nature of input data, data complexity and noise, parameters selection, data visualizations, heterogeneity of data, accuracy, and large-scale and high-dimensional data are investigated. Finally, the challenges that require substantial research efforts and future directions are summarized.
Redhwan Al-Amri; Raja Murugesan; Mustafa Man; Alaa Abdulateef; Mohammed Al-Sharafi; Ammar Alkahtani. A Review of Machine Learning and Deep Learning Techniques for Anomaly Detection in IoT Data. Applied Sciences 2021, 11, 5320 .
AMA StyleRedhwan Al-Amri, Raja Murugesan, Mustafa Man, Alaa Abdulateef, Mohammed Al-Sharafi, Ammar Alkahtani. A Review of Machine Learning and Deep Learning Techniques for Anomaly Detection in IoT Data. Applied Sciences. 2021; 11 (12):5320.
Chicago/Turabian StyleRedhwan Al-Amri; Raja Murugesan; Mustafa Man; Alaa Abdulateef; Mohammed Al-Sharafi; Ammar Alkahtani. 2021. "A Review of Machine Learning and Deep Learning Techniques for Anomaly Detection in IoT Data." Applied Sciences 11, no. 12: 5320.
A severe energy crisis has plagued Yemen for decades, and most of the population lack access to electricity. This has harmed the country’s economic, social, and industrial growth. Yemen generates electricity mainly from fossil fuels, despite having a high potential for renewable energy. Unfortunately, the situation has recently been compounded by the country’s continuing war, which has been ongoing since early 2015. It has impacted the country’s energy infrastructure negatively, resulting in power outages. Therefore, this paper aims to provide an updated perspective on Yemen’s current energy crisis and explain its key issues and potential solutions. Besides, it examines the potential, development, and current state of renewable energy sources, such as solar, wind, geothermal, and biomass. Based on the findings, Yemen is one of the world’s wealthiest countries in terms of sunlight and wind speed, and these two resources are abundant in all regions of the country. In addition, this paper sheds light on the solar energy revolution that has arisen since the war started due to the complete outage of the national electricity. Within a few years, solar energy in Yemen has increased its capacity by 50 times and has recently become the primary source of electricity for most Yemenis. Furthermore, the paper discusses the difficulties and challenges that face the implementation of renewable energy investment projects. Numerous recommendations for potential improvements in Yemen’s widespread use of renewable energy are also provided in this paper. All of the ideas presented in this paper are hoped to increase the efforts to grow renewable energy production in Yemen, thereby solving the issues of energy poverty and reducing environmental effects. The presented analysis can be used as a scientific reference for researchers and industrial companies looking for suitable solutions to advance Yemen’s renewable energy.
Ali Q. Al-Shetwi; M. A. Hannan; Majid A. Abdullah; M. S. A. Rahman; Pin Jern Ker; Ammar A. Alkahtani; T. M. Indra Mahlia; K. M. Muttaqi. Utilization of Renewable Energy for Power Sector in Yemen: Current Status and Potential Capabilities. IEEE Access 2021, 9, 79278 -79292.
AMA StyleAli Q. Al-Shetwi, M. A. Hannan, Majid A. Abdullah, M. S. A. Rahman, Pin Jern Ker, Ammar A. Alkahtani, T. M. Indra Mahlia, K. M. Muttaqi. Utilization of Renewable Energy for Power Sector in Yemen: Current Status and Potential Capabilities. IEEE Access. 2021; 9 ():79278-79292.
Chicago/Turabian StyleAli Q. Al-Shetwi; M. A. Hannan; Majid A. Abdullah; M. S. A. Rahman; Pin Jern Ker; Ammar A. Alkahtani; T. M. Indra Mahlia; K. M. Muttaqi. 2021. "Utilization of Renewable Energy for Power Sector in Yemen: Current Status and Potential Capabilities." IEEE Access 9, no. : 79278-79292.
Recent achievements, based on lead (Pb) halide perovskites, have prompted comprehensive research on low-cost photovoltaics, in order to avoid the major challenges that arise in this respect: Stability and toxicity. In this study, device modelling of lead (Pb)-free perovskite solar cells has been carried out considering methyl ammonium tin bromide (CH3NH3SnBr3) as perovskite absorber layer. The perovskite structure has been justified theoretically by Goldschmidt tolerance factor and the octahedral factor. Numerical modelling tools were used to investigate the effects of amphoteric defect and interface defect states on the photovoltaic parameters of CH3NH3SnBr3-based perovskite solar cell. The study identifies the density of defect tolerance in the absorber layer, and that both the interfaces are 1015 cm−3, and 1014 cm−3, respectively. Furthermore, the simulation evaluates the influences of metal work function, uniform donor density in the electron transport layer and the impact of series resistance on the photovoltaic parameters of proposed n-TiO2/i-CH3NH3SnBr3/p-NiO solar cell. Considering all the optimization parameters, CH3NH3SnBr3-based perovskite solar cell exhibits the highest efficiency of 21.66% with the Voc of 0.80 V, Jsc of 31.88 mA/cm2 and Fill Factor of 84.89%. These results divulge the development of environmentally friendly methyl ammonium tin bromide perovskite solar cell.
Samiul Islam; K. Sobayel; Ammar Al-Kahtani; M. Islam; Ghulam Muhammad; N. Amin; Shahiduzzaman; Akhtaruzzaman. Defect Study and Modelling of SnX3-Based Perovskite Solar Cells with SCAPS-1D. Nanomaterials 2021, 11, 1218 .
AMA StyleSamiul Islam, K. Sobayel, Ammar Al-Kahtani, M. Islam, Ghulam Muhammad, N. Amin, Shahiduzzaman, Akhtaruzzaman. Defect Study and Modelling of SnX3-Based Perovskite Solar Cells with SCAPS-1D. Nanomaterials. 2021; 11 (5):1218.
Chicago/Turabian StyleSamiul Islam; K. Sobayel; Ammar Al-Kahtani; M. Islam; Ghulam Muhammad; N. Amin; Shahiduzzaman; Akhtaruzzaman. 2021. "Defect Study and Modelling of SnX3-Based Perovskite Solar Cells with SCAPS-1D." Nanomaterials 11, no. 5: 1218.
With the rise in the demand for electric vehicles, the need for a reliable charging infrastructure increases to accommodate the rapid public adoption of this type of transportation. Simultaneously, local electricity grids are being under pressure and require support from naturally abundant and inexpensive alternative energy sources such as wind and solar. This is why the world has recently witnessed the emergence of renewable energy-based charging stations that have received great acclaim. In this paper, we review studies related to this type of alternative energy charging infrastructure. We provide comprehensive research covering essential aspects in this field, including resources, potentiality, planning, control, and pricing. The study also includes studying and clarifying challenges facing this type of electric charging station and proposing suitable solutions for those challenges. The paper aims to provide the reader with an overview of charging electric vehicles through renewable energy and establishing the ground for further research in this vital field.
Gamal Alkawsi; Yahia Baashar; Dallatu Abbas U; Ammar Alkahtani; Sieh Tiong. Review of Renewable Energy-Based Charging Infrastructure for Electric Vehicles. Applied Sciences 2021, 11, 3847 .
AMA StyleGamal Alkawsi, Yahia Baashar, Dallatu Abbas U, Ammar Alkahtani, Sieh Tiong. Review of Renewable Energy-Based Charging Infrastructure for Electric Vehicles. Applied Sciences. 2021; 11 (9):3847.
Chicago/Turabian StyleGamal Alkawsi; Yahia Baashar; Dallatu Abbas U; Ammar Alkahtani; Sieh Tiong. 2021. "Review of Renewable Energy-Based Charging Infrastructure for Electric Vehicles." Applied Sciences 11, no. 9: 3847.
Fabrication of quasi-solid state polymer electrolytes are recently being endorsed by electrochemists due to its superior electrical and physical properties. With the aspiration to develop a sustainable electrolyte component, this study is a novel attempt to fabricate quasi-solid electrolyte based on esterified starch. Potato starch was chemically modified via simple phthaloylation method. The resulting amorphous, hydrophobic starch derivative was used as a polymer base to prepare cost effective thermoplastic gel electrolytes via incorporation of propylene carbonate, dimethylformamide and lithium iodide. Fourier transform infrared spectroscopy and X-ray diffraction characterizations verified the impact of phthaloylation and plasticization in suppressing the crystallinity and hydrophilicity of starch. The biopolymer gel with 40 wt.% LiI recorded the highest room temperature ionic conductivity of 4.82 mS cm−1. The sample with highest ionic conductivity recorded the best efficiency of 3.56%, which is one of the highest values for starch electrolyte-based dye-sensitized solar cells (DSSC). The optimized efficiency indicate that starch-based electrolyte has good prospects for fabrication of quasi-solid DSSC.
Vidhya Selvanathan; Mohd Hafidz Ruslan; Ammar Ahmed Nasser Alkahtani; Nowshad Amin; Kamaruzzaman Sopian; Ghulam Muhammad; Akhtaruzzaman. Organosoluble, esterified starch as quasi-solid biopolymer electrolyte in dye-sensitized solar cell. Journal of Materials Research and Technology 2021, 12, 1638 -1648.
AMA StyleVidhya Selvanathan, Mohd Hafidz Ruslan, Ammar Ahmed Nasser Alkahtani, Nowshad Amin, Kamaruzzaman Sopian, Ghulam Muhammad, Akhtaruzzaman. Organosoluble, esterified starch as quasi-solid biopolymer electrolyte in dye-sensitized solar cell. Journal of Materials Research and Technology. 2021; 12 ():1638-1648.
Chicago/Turabian StyleVidhya Selvanathan; Mohd Hafidz Ruslan; Ammar Ahmed Nasser Alkahtani; Nowshad Amin; Kamaruzzaman Sopian; Ghulam Muhammad; Akhtaruzzaman. 2021. "Organosoluble, esterified starch as quasi-solid biopolymer electrolyte in dye-sensitized solar cell." Journal of Materials Research and Technology 12, no. : 1638-1648.
The positive effects of interest on different aspects, e.g., learning and education, economy, psychological well-being, and social relations, have been widely addressed by many psychological and physiological studies in the last two decades. While the psychological work has investigated this impact of interest theoretically, the physiological studies have focused more on the modulatory effects. However, some studies have addressed both sides of the effects. In this work, we conduct a comprehensive review of physiological studies on interest detection, from different perspectives carried out between 2003 and 2019. A lack of connection between the psychological and physiological studies was identified. Therefore, this paper aims to integrate the unique psychological and physiological aspects and characteristics of interest to form a base for future research by considering the pros and cons of the included studies. For example, considering the two types of interest (situational and individual) the detected interest in learning, gaming, and advertisement’s physiological experiments could be referring specifically to situational interest. Hence, bridging the gap between both physiological and psychological studies is essential for improving the research on interest. Furthermore, we propose several suggestions for future work direction.
Areej Babiker; Yahia Baashar; Ammar Ahmed Alkahtani; Ibrahima Faye; Gamal Alkawsi. Towards Detection of Interest Using Physiological Sensors. Applied Sciences 2021, 11, 1318 .
AMA StyleAreej Babiker, Yahia Baashar, Ammar Ahmed Alkahtani, Ibrahima Faye, Gamal Alkawsi. Towards Detection of Interest Using Physiological Sensors. Applied Sciences. 2021; 11 (3):1318.
Chicago/Turabian StyleAreej Babiker; Yahia Baashar; Ammar Ahmed Alkahtani; Ibrahima Faye; Gamal Alkawsi. 2021. "Towards Detection of Interest Using Physiological Sensors." Applied Sciences 11, no. 3: 1318.
Precise wind speed prediction is a key factor in many energy applications, especially when wind energy is integrated with power grids. However, because of the intermittent and nonstationary nature of wind speed, modeling and predicting it is a challenge. In addition, using uncorrelated multivariate variables as exogenous input variables often adversely impacts the performance of prediction models. In this paper, we present a multistep short-term wind speed prediction using multivariate exogenous input variables. We implement different variable selection methods to select the best set of variables that significantly improve the performance of prediction models. We evaluate the performance of eight transfer learning methods, four shallow neural networks (NNs), and the persistence method on predicting the future values of wind speed using ultrashort-term, short-term, and multistep time horizons. We performed the evaluation over two-year high-sampled wind speed data averaged at 10-minute intervals. Results show that Nonlinear Auto-Regressive Exogenous (NARX) model outperformed all other methods, achieving an average mean absolute error (MAE) and root mean square error (RMSE) of 0.2205 and 0.3405 for multistep predictions, respectively. Despite the lower performance of the transfer learning methods (i.e., 0.43 and 0.58 for MAE and RMSE, respectively), it is believed that results could be further improved with a better enhancement of the feature selection and model parameters.
Fuad Noman; Gamal Alkawsi; Ammar Ahmed Alkahtani; Ali Q. Al-Shetwi; Sieh Kiong Tiong; Nasser Alalwan; Janaka Ekanayake; Ahmed Ibrahim Alzahrani. Multistep short-term wind speed prediction using nonlinear auto-regressive neural network with exogenous variable selection. Alexandria Engineering Journal 2020, 60, 1221 -1229.
AMA StyleFuad Noman, Gamal Alkawsi, Ammar Ahmed Alkahtani, Ali Q. Al-Shetwi, Sieh Kiong Tiong, Nasser Alalwan, Janaka Ekanayake, Ahmed Ibrahim Alzahrani. Multistep short-term wind speed prediction using nonlinear auto-regressive neural network with exogenous variable selection. Alexandria Engineering Journal. 2020; 60 (1):1221-1229.
Chicago/Turabian StyleFuad Noman; Gamal Alkawsi; Ammar Ahmed Alkahtani; Ali Q. Al-Shetwi; Sieh Kiong Tiong; Nasser Alalwan; Janaka Ekanayake; Ahmed Ibrahim Alzahrani. 2020. "Multistep short-term wind speed prediction using nonlinear auto-regressive neural network with exogenous variable selection." Alexandria Engineering Journal 60, no. 1: 1221-1229.
Despite the significant progress in the understanding of the phenomenon of lightning and the physics behind it, locating and mapping its occurrence remain a challenge. Such localization and mapping of very high frequency (VHF) lightning radiation sources provide a foundation for the subsequent research on predicting lightning, saving lives, and protecting valuable assets. A major technical challenge in attempting to map the sources of lightning is mapping accuracy. The three common electromagnetic radio frequency-based lightning locating techniques are magnetic direction finder, time of arrival, and interferometer (ITF). Understanding these approaches requires critically reviewing previous attempts. The performance and reliability of each method are evaluated on the basis of the mapping accuracy obtained from lightning data from different sources. In this work, we review various methods for lightning mapping. We study the approaches, describe their techniques, analyze their merits and demerits, classify them, and derive few opportunities for further research. We find that the ITF system is the most effective method and that its performance may be improved further. One approach is to improve how lightning signals are preprocessed and how noise is filtered. Signal processing can also be utilized to improve mapping accuracy by introducing methods such as wavelet transform in place of conventional cross-correlation approaches.
Ammar Alammari; Ammar Ahmed Alkahtani; Mohd Riduan Ahmad; Fuad M. Noman; Mona Riza Mohd Esa; Zen Kawasaki; Sieh Kiong Tiong. Lightning Mapping: Techniques, Challenges, and Opportunities. IEEE Access 2020, 8, 190064 -190082.
AMA StyleAmmar Alammari, Ammar Ahmed Alkahtani, Mohd Riduan Ahmad, Fuad M. Noman, Mona Riza Mohd Esa, Zen Kawasaki, Sieh Kiong Tiong. Lightning Mapping: Techniques, Challenges, and Opportunities. IEEE Access. 2020; 8 ():190064-190082.
Chicago/Turabian StyleAmmar Alammari; Ammar Ahmed Alkahtani; Mohd Riduan Ahmad; Fuad M. Noman; Mona Riza Mohd Esa; Zen Kawasaki; Sieh Kiong Tiong. 2020. "Lightning Mapping: Techniques, Challenges, and Opportunities." IEEE Access 8, no. : 190064-190082.
This paper presents a new capsule-shaped sensor to detect the glucose concentration in the human body. The model under study was formulated by relying on the index change in the refractive index (RI) because of the change in the sample that infiltrated the cavity. The index of refraction change is accompanied by modifying the resonant wavelength. The recommended model has considered the simple shape and ease of manufacture, along with other characteristics such as sensitivity and a low detection limit. The results report a high sensitivity of S = 546.72 nm/RI unit (RIU), a high quality factor of Q = 2066.24, a low detection limit of DL = 1.44 × 10−4 RIU, and a high value of transmission of 97%, which are considered to be sufficient and efficient in detecting measured material. This proposed model provides many opportunities and is promising for the manufacture of different types of sensing detection devices.
Mouhssin Maache; Yousef Fazea; Ismail Bile Hassan; Ammar Ahmed Alkahtani; Ikram Ud Din. High-Sensitivity Capsule-Shaped Sensor Based on 2D Photonic Crystals. Symmetry 2020, 12, 1480 .
AMA StyleMouhssin Maache, Yousef Fazea, Ismail Bile Hassan, Ammar Ahmed Alkahtani, Ikram Ud Din. High-Sensitivity Capsule-Shaped Sensor Based on 2D Photonic Crystals. Symmetry. 2020; 12 (9):1480.
Chicago/Turabian StyleMouhssin Maache; Yousef Fazea; Ismail Bile Hassan; Ammar Ahmed Alkahtani; Ikram Ud Din. 2020. "High-Sensitivity Capsule-Shaped Sensor Based on 2D Photonic Crystals." Symmetry 12, no. 9: 1480.
The integration of large-scale wind farms and large-scale charging stations for electric vehicles (EVs) into electricity grids necessitates energy storage support for both technologies. Matching the variability of the energy generation of wind farms with the demand variability of the EVs could potentially minimize the size and need for expensive energy storage technologies required to stabilize the grid. This paper investigates the feasibility of using the wind as a direct energy source to power EV charging stations. An interval-based approach corresponding to the time slot taken for EV charging is introduced for wind energy conversion and analyzed using different constraints and criteria, including the wind speed averaging time interval, various turbines manufacturers, and standard high-resolution wind speed datasets. A quasi-continuous wind turbine’s output energy is performed using a piecewise recursive approach to measure the EV charging effectiveness. Wind turbine analysis using two years of wind speed data shows that the application of direct wind-to-EV is able to provide sufficient constant power to supply the large-scale charging stations. The results presented in this paper confirm that the potential of direct powering of EV charging stations by wind has merits and that research in this direction is worth pursuing.
Fuad Noman; Ammar Ahmed Alkahtani; Vassilios Agelidis; Kiong Sieh Tiong; Gamal Alkawsi; Janaka Ekanayake. Wind-Energy-Powered Electric Vehicle Charging Stations: Resource Availability Data Analysis. Applied Sciences 2020, 10, 5654 .
AMA StyleFuad Noman, Ammar Ahmed Alkahtani, Vassilios Agelidis, Kiong Sieh Tiong, Gamal Alkawsi, Janaka Ekanayake. Wind-Energy-Powered Electric Vehicle Charging Stations: Resource Availability Data Analysis. Applied Sciences. 2020; 10 (16):5654.
Chicago/Turabian StyleFuad Noman; Ammar Ahmed Alkahtani; Vassilios Agelidis; Kiong Sieh Tiong; Gamal Alkawsi; Janaka Ekanayake. 2020. "Wind-Energy-Powered Electric Vehicle Charging Stations: Resource Availability Data Analysis." Applied Sciences 10, no. 16: 5654.
A microgrid (MG) is a small-scale power system with a cluster of loads and distributed generators operating together through energy management software and devices that act as a single controllable entity with respect to the grid. MG has become a key research element in smart grid and distribution power systems. MG mainly contains different renewable energy sources (RESs) that use various technological advancements, such as power electronics-based technologies. However, it has an unstable output, thereby causing different types of power quality (PQ) events. As a result, standards and mitigation methods have been developed in recent years. To mitigate PQ issues due to MG integration, various methods and standards have been proposed over the last years. Although these individual methods are well documented, a comparative overview had not been introduced so far. Thus, this study aims to fill the gap by reviewing and comparing the prior-art PQ issues, solutions, and standards in MGs. We compare the main issues related to voltage sag, voltage swell, voltage and current harmonics, system unbalances, and fluctuations to ensure high-quality MG output power. The new technologies associated with MGs generate harmonics emission in the range of 2–150 kHz, thereby causing a new phenomenon, namely, supraharmonics (SH) emission, which is not sufficiently covered in the literature. Therefore, the characteristics, causes, consequences, and measurements of SH are highlighted and analyzed. The mitigation strategies, control, and devices of PQ issues are also discussed. Moreover, a comparison is conducted between the most popular devices used to mitigate the PQ issues in MG in terms of cost, rating, and different aspects of performance. This review study can strengthen the efforts toward the mitigation and standards development of PQ issues in MG applications, especially SH. Finally, some recommendations and suggestions to improve PQ of MG, including SH, are highlighted.
Ammar Ahmed Alkahtani; Saad T. Y. Alfalahi; Abedalgany Abedallah Athamneh; Ali Q. Al-Shetwi; Muhamad Bin Mansor; M. A. Hannan; Vassilios G. Agelidis. Power Quality in Microgrids Including Supraharmonics: Issues, Standards, and Mitigations. IEEE Access 2020, 8, 127104 -127122.
AMA StyleAmmar Ahmed Alkahtani, Saad T. Y. Alfalahi, Abedalgany Abedallah Athamneh, Ali Q. Al-Shetwi, Muhamad Bin Mansor, M. A. Hannan, Vassilios G. Agelidis. Power Quality in Microgrids Including Supraharmonics: Issues, Standards, and Mitigations. IEEE Access. 2020; 8 (99):127104-127122.
Chicago/Turabian StyleAmmar Ahmed Alkahtani; Saad T. Y. Alfalahi; Abedalgany Abedallah Athamneh; Ali Q. Al-Shetwi; Muhamad Bin Mansor; M. A. Hannan; Vassilios G. Agelidis. 2020. "Power Quality in Microgrids Including Supraharmonics: Issues, Standards, and Mitigations." IEEE Access 8, no. 99: 127104-127122.
In recent years, wind energy has gained extensive attention in the recent years in various countries due to the high energy demand of energy and shortage of traditional electric energy sources. Because wind energy constitutes a cost effective and environmentally friendly source, it can significantly contribute toward the reduction of the ever-increasing carbon emissions. It is one of the fastest growing green technologies worldwide, with a total generation share of 564 GW as of the end of 2018. In Malaysia, wind energy has been a hot topic in both academia and green energy industry. In this paper, the current status of wind energy research in Malaysia is reviewed. Different contributing factors such as potentiality and assessments, wind speed and direction modeling, wind prediction and spatial mapping, and optimal sizing of wind farms are extensively discussed. This paper discusses the progress of all studies related to wind energy and presents conclusions and recommendations for improving wind energy research in Malaysia.
Fuad Noman; Gamal Abdulnaser Alkawsi; Dallatu Abbas; Ammar Ahmed Alkahtani; Seih Kiong Tiong; Janaka Ekanayake. Comprehensive Review of Wind Energy in Malaysia: Past, Present, and Future Research Trends. IEEE Access 2020, 8, 124526 -124543.
AMA StyleFuad Noman, Gamal Abdulnaser Alkawsi, Dallatu Abbas, Ammar Ahmed Alkahtani, Seih Kiong Tiong, Janaka Ekanayake. Comprehensive Review of Wind Energy in Malaysia: Past, Present, and Future Research Trends. IEEE Access. 2020; 8 (99):124526-124543.
Chicago/Turabian StyleFuad Noman; Gamal Abdulnaser Alkawsi; Dallatu Abbas; Ammar Ahmed Alkahtani; Seih Kiong Tiong; Janaka Ekanayake. 2020. "Comprehensive Review of Wind Energy in Malaysia: Past, Present, and Future Research Trends." IEEE Access 8, no. 99: 124526-124543.
Lightning mapping systems based on perpendicular crossed baseline interferometer (ITF) technology have been developed rapidly in recent years. Several processing methods have been proposed to estimate the temporal location and spatial map of lightning strikes. In this paper, a single very high frequency (VHF) ITF is used to simulate and augment the lightning maps. We perform a comparative study of using different processing techniques and procedures to enhance the localization and mapping of lightning VHF radiation. The benchmark environment involves the use of different noise reduction and cross-correlation methods. Moreover, interpolation techniques are introduced to smoothen the correlation peaks for more accurate lightning localization. A positive narrow bipolar event (NBE) lightning discharge is analyzed and the mapping procedure is confirmed using both simulated and measured lightning signals. The results indicate that a good estimation of lightning radiation sources is achieved when using wavelet denoising and cross-correlations in wavelet-domain (CCWD) with a minimal error of 3.46°. The investigations carried out in this study confirm that the ITF mapping system could effectively map the lightning VHF radiation source.
Ammar Alammari; Ammar A. Alkahtani; Mohd Riduan Ahmad; Fuad Noman; Mona Riza Mohd Esa; Muhammad Haziq Mohammad Sabri; Sulaiman Ali Mohammad; Ahmed Salih Al-Khaleefa; Zen Kawasaki; Vassilios Agelidis. Kalman Filter and Wavelet Cross-Correlation for VHF Broadband Interferometer Lightning Mapping. Applied Sciences 2020, 10, 4238 .
AMA StyleAmmar Alammari, Ammar A. Alkahtani, Mohd Riduan Ahmad, Fuad Noman, Mona Riza Mohd Esa, Muhammad Haziq Mohammad Sabri, Sulaiman Ali Mohammad, Ahmed Salih Al-Khaleefa, Zen Kawasaki, Vassilios Agelidis. Kalman Filter and Wavelet Cross-Correlation for VHF Broadband Interferometer Lightning Mapping. Applied Sciences. 2020; 10 (12):4238.
Chicago/Turabian StyleAmmar Alammari; Ammar A. Alkahtani; Mohd Riduan Ahmad; Fuad Noman; Mona Riza Mohd Esa; Muhammad Haziq Mohammad Sabri; Sulaiman Ali Mohammad; Ahmed Salih Al-Khaleefa; Zen Kawasaki; Vassilios Agelidis. 2020. "Kalman Filter and Wavelet Cross-Correlation for VHF Broadband Interferometer Lightning Mapping." Applied Sciences 10, no. 12: 4238.
We report the effect of substrate temperature (25–300 °C) on the structural, optical and electrical properties of Cadmium Sulphide (CdS) thin films deposited onto glass substrate by Radio Frequency (RF) magnetron sputtering. The structural, morphological, optical and electrical properties of the films were characterized by X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), UV–VIS-NIR spectroscopy and Hall Effect measurement respectively. The XRD studies showed that the films were polycrystalline with hexagonal wurtzite structure preferentially oriented along the (0 0 2) plane parallel to the substrate surface. The XRD data analysis further revealed the crystallite size of the nanocrystalline films i.e. 22–24 nm exhibiting the fact that crystallite size increased with increasing the substrate temperature. The FE-SEM images along with energy dispersive spectroscopy (EDS) studies confirmed the homogeneous, compact and pin-hole free surface morphology. The UV–VIS-NIR studies unveiled the optical transmittance in the range of 75–90% after 540 nm of the wavelength of light. The optical band gaps were found to be decreasing from 2.34 eV to 2.26 eV with increasing the substrate temperature. The films were characterized as n-type as evidenced by the Hall Effect measurement. The carrier mobility was found to be increasing gradually from 5.53 to 12.57 cm2/V·s by increasing the substrate temperature from room temperature to 300 °C due to the improvement of crystalline quality and grain size of the films. The results showed good optical and electrical properties of the films deposited at 300 °C which are suitable to use as window layer in thin film based solar cells.
N.K. Das; J. Chakrabartty; Syed Farid Uddin Farhad; A.K. Sen Gupta; E.M.K. Ikball Ahamed; K.S. Rahman; A. Wafi; Ammar Ahmed Nasser Alkahtani; M.A. Matin; Nowshad Amin. Effect of substrate temperature on the properties of RF sputtered CdS thin films for solar cell applications. Results in Physics 2020, 17, 103132 .
AMA StyleN.K. Das, J. Chakrabartty, Syed Farid Uddin Farhad, A.K. Sen Gupta, E.M.K. Ikball Ahamed, K.S. Rahman, A. Wafi, Ammar Ahmed Nasser Alkahtani, M.A. Matin, Nowshad Amin. Effect of substrate temperature on the properties of RF sputtered CdS thin films for solar cell applications. Results in Physics. 2020; 17 ():103132.
Chicago/Turabian StyleN.K. Das; J. Chakrabartty; Syed Farid Uddin Farhad; A.K. Sen Gupta; E.M.K. Ikball Ahamed; K.S. Rahman; A. Wafi; Ammar Ahmed Nasser Alkahtani; M.A. Matin; Nowshad Amin. 2020. "Effect of substrate temperature on the properties of RF sputtered CdS thin films for solar cell applications." Results in Physics 17, no. : 103132.
This paper presents a compact microstrip ultra-high frequency (UHF) reader patch antenna with complementary split ring resonator (CSRR) for radio frequency identification (RFID). The total size of the antenna is 208 × 208 × 1.6 mm3. The proposed antenna is designed, fabricated and measured in order to verify the proposed concept. The characterization for radiation parameters, like return loss, radiation pattern and antenna gain have been done experimentally. The proposed antenna is operated at 921 MHz for and achieved a gain of 8.285 dBi. All simulations in this work have been carried out by means of the commercial computer simulation technology (CST) software. In compare to the simulated results, the measured outcomes are promised.
Syamimi Mohd Norzeli; Ismarani Ismail; Norashidah Md Din; Mohd Tarmizi Ali; Ali AlMisreb; Ammar Ahmed Nasser Alkahtani. A rectangular CSRR based microstrip UHF reader patch antenna for RFID applications. Indonesian Journal of Electrical Engineering and Computer Science 2020, 17, 1434 -1441.
AMA StyleSyamimi Mohd Norzeli, Ismarani Ismail, Norashidah Md Din, Mohd Tarmizi Ali, Ali AlMisreb, Ammar Ahmed Nasser Alkahtani. A rectangular CSRR based microstrip UHF reader patch antenna for RFID applications. Indonesian Journal of Electrical Engineering and Computer Science. 2020; 17 (3):1434-1441.
Chicago/Turabian StyleSyamimi Mohd Norzeli; Ismarani Ismail; Norashidah Md Din; Mohd Tarmizi Ali; Ali AlMisreb; Ammar Ahmed Nasser Alkahtani. 2020. "A rectangular CSRR based microstrip UHF reader patch antenna for RFID applications." Indonesian Journal of Electrical Engineering and Computer Science 17, no. 3: 1434-1441.
The generation and integration of photovoltaic power plants (PVPPs) into the utility grid have increased dramatically over the past two decades. In this sense, and to ensure a high quality of the PVPPs generated power as well as a contribution on the power system security and stability, some of the new power quality requirements imposed by different grid codes and standards in order to regulate the installation of PVPPs and ensure the grid stability. This study aims to investigate the recent integration requirements including voltage sag, voltage flicker, harmonics, voltage unbalance, and frequency variation. Additionally, compliance controls and methods to fulfill these requirements are developed. In line with this, a large-scale three-phase grid-connected PVPP is designed. A modified inverter controller without the use of any extra device is designed to mitigate the sage incidence and achieve the low-voltage ride-through requirement. It can efficiently operate at normal conditions and once sag or faults are detected, it can change the mode of operation and inject a reactive current based on the sag depth. A dynamic voltage regulator and its controller are also designed to control the voltage flicker, fluctuation, and unbalance at the point of common coupling between the PVPP and the grid. The voltage and current harmonics are reduced below the specified limits using proper design and a RLC filter. The obtained results show that the proposed controller fulfilled the recent standard requirements in mitigating power quality (PQ) events. Thus, this study can increase the effort towards the development of smooth PVPP integration by optimizing the design, operation and control strategies towards high PQ and green electricity.
Ali Q. Al-Shetwi; M A Hannan; Ker Pin Jern; Ammar A. Alkahtani; A. E. Pg Abas. Power Quality Assessment of Grid-Connected PV System in Compliance with the Recent Integration Requirements. Electronics 2020, 9, 366 .
AMA StyleAli Q. Al-Shetwi, M A Hannan, Ker Pin Jern, Ammar A. Alkahtani, A. E. Pg Abas. Power Quality Assessment of Grid-Connected PV System in Compliance with the Recent Integration Requirements. Electronics. 2020; 9 (2):366.
Chicago/Turabian StyleAli Q. Al-Shetwi; M A Hannan; Ker Pin Jern; Ammar A. Alkahtani; A. E. Pg Abas. 2020. "Power Quality Assessment of Grid-Connected PV System in Compliance with the Recent Integration Requirements." Electronics 9, no. 2: 366.