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Impacts of Electrical Line Losses Comprising Mul-ti-Distributed Generation in Distribution System 被引量:1
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作者 Surakit Thongsuk Atthapol Ngaopitakkul 《Energy and Power Engineering》 2013年第4期1037-1042,共6页
This paper proposes to study the impacts of electrical line losses due to the connection of distributed generators (DG) to 22kV distribution system of Provincial Electricity Authority (PEA). Data of geographic informa... This paper proposes to study the impacts of electrical line losses due to the connection of distributed generators (DG) to 22kV distribution system of Provincial Electricity Authority (PEA). Data of geographic information systems (GIS) including the distance of distribution line and location of load being key parameter of PEA is simulated using digital simulation and electrical network calculation program (DIgSILENT) to analyze power loss of the distribution system. In addition, the capacity and location of DG installed into the distribution system is considered. The results are shown that, when DG is installed close to the substation, the electrical line losses are reduced. However, if DG capacity becomes larger and the distance between DG and load is longer, the electrical line losses tend to increase. The results of this paper can be used to create the suitability and fairness of the fee for both DG and utility. 展开更多
关键词 ELECTRICAL LOSS Distributed Generation Distribution System RENEWABLE Energy
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Electrical Performance and Effect of Frequency Electromagnetic Waves on Subterranean Termites <i>Coptotermes curvignathus</i>Holmgren
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作者 Seno D. Panjaitan Farah Diba +1 位作者 Ferry Hadary Tsuyoshi Yoshimura 《Journal of Electromagnetic Analysis and Applications》 2014年第1期1-7,共7页
The research aimed to propose a non-destructive technology to control subterranean termites Coptotermes curvignathus Holmgren infestation based on electromagnetic waves. A portable apparatus for this technology has be... The research aimed to propose a non-destructive technology to control subterranean termites Coptotermes curvignathus Holmgren infestation based on electromagnetic waves. A portable apparatus for this technology has been built and its experiment is presented in this paper. Some electrical parameters were measured and analyzed along with their effects to the termites. The experiment using frequency range between 30 Hz - 600 kHz has been done. The average error of the apparatus by comparing the result with the direct measurement using oscilloscope was also measured. The highest error value appeared at 600 kHz with frequency error 6.05 kHz. The highest error of voltage (i.e. 0.186 Volt) appeared at 100 kHz. For safetiness, the highest magnetic field at 300 kHz was 0.1815 μT and at 500 kHz was 0.00725 μT which were safe for human. The average value of termites mortality was higher on irradiation time 120 minutes than 60 minutes respectively in all test frequency: 300 kHz, 400 kHz, 500 kHz and 600 kHz. This paper presents an important information of the electromagnatic-based technology for environmental friendly termites control in spite of using the insecticides. 展开更多
关键词 Electromagnetic Waves FREQUENCY SUBTERRANEAN TERMITES COPTOTERMES curvignathus TERMITES Infestation
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Protective effects of turmeric extract,curcumin,demethoxycurcumin,bis-demethoxycurcumin,and ar-turmerone from Curcuma longa L.rhizomes on acetaminophen-induced hepatotoxicity in HepG2 cells 被引量:1
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作者 Wahyu Widowati Dian Ratih Laksmitawati +9 位作者 Diah Kartika Pratami Deni Rahmat S.Ravi Kiran J.Achyutha Devi Didik Priyandoko Nindia Salsabila Mia Dewi Annisa Firdaus Sutendi Rizal Azis Dhanar Septyawan Hadiprasetyo Mariska Elizabeth 《Asian Pacific Journal of Tropical Biomedicine》 2025年第6期251-262,共12页
Objective:To assess the effects of turmeric extract and its compounds on oxidative stress,inflammation,and apoptosis in acetaminophen-induced liver injury.Methods:HepG2 cells were administered with acetaminophen(40 mM... Objective:To assess the effects of turmeric extract and its compounds on oxidative stress,inflammation,and apoptosis in acetaminophen-induced liver injury.Methods:HepG2 cells were administered with acetaminophen(40 mM)to induce hepatotoxicity,followed by treatment with turmeric extract and its isolated compounds including curcumin,demethoxycurcumin,bis-demethoxycurcumin and ar-turmerone at 5,25,and 125μg/mL.IL-1β,IL-6,and IL-10 levels were quantified with ELISA kits.Further,qRT-PCR was used to analyze the mRNA expression of JNK,Casp-9,and Casp-3.Meanwhile,the levels of nitric oxide and lactate dehydrogenase were analyzed using colorimetric assay.Results:Acetaminophen administration caused an increase in the levels of lactate dehydrogenase,nitric oxide,IL-1β,IL-6,and the mRNA expression of JNK,Casp-9,and Casp-3 in HepG2 cells while reducing IL-10 levels.Treatment with turmeric extract,curcumin,demethoxycurcumin,bis-demethoxycurcumin,and ar-turmerone lowered IL-1β,IL-6,nitric oxide,and lactate dehydrogenase levels,downregulated the mRNA expression of JNK,Casp-9,and Casp-3,and increased IL-10 levels.Conclusions:Turmeric extract and its compounds have significant hepatoprotective activity and could be further explored for the treatment of liver damage. 展开更多
关键词 ACETAMINOPHEN Apoptosis Curcuma longa CURCUMIN HEPATOTOXICITY Inflammation Oxidative stress
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Superiority of Strontium-Doped Barium Titanate as an Electron Transport for Perovskite Solar Cells for Enhanced Efficiency and Thermal Stability
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作者 Minhaz Mahmood Mohammad Tariqul Islam +7 位作者 Md Samiul Islam Sakhr M.Sultan Kashfia Noor M.A.Islam K.Sopian Abdullah Alghafis Mohd Adib Ibrahim K.Sobayel 《Transactions of Tianjin University》 2025年第1期42-63,共22页
This study presents a detailed comparative analysis of three electron transport layer(ETL)materials for perovskite solar cells(PSCs),namely titanium dioxide(TiO_(2)),barium titanate(BaTiO_(3)or BTO),and strontium-dope... This study presents a detailed comparative analysis of three electron transport layer(ETL)materials for perovskite solar cells(PSCs),namely titanium dioxide(TiO_(2)),barium titanate(BaTiO_(3)or BTO),and strontium-doped barium titan-ate(Ba_(1−x)Sr_(x)TiO_(3)or BST),and their impact on the quantum efficiency(QE)and power conversion efficiency(PCE)of CH_(3)NH_(3)PbI_(3)(MAPbI_(3))PSCs.The optimized structure demonstrates that devices utilizing BST as an ETL achieved the highest PCE of 29.85%,exhibiting superior thermal stability with the lowest temperature coefficient of−0.43%/K.This temperature-induced degradation is comparable to that of commercially available silicon cells.Furthermore,BST-based ETLs show 29.50%and 26.48%higher PCE than those of TiO_(2)-based and BTO-based ETLs.The enhanced internal QE and favorable current density–voltage(J–V)characteristics of BST compared with those of TiO_(2)and BTO are attributed to its improved charge carrier separation,reduced recombination rates,and robust electrical characteristics under varied environmental conditions.Furthermore,the electric field and generation rate of the BST-based ETLs show a more favorable distribution than those of the TiO_(2)-based and BTO-based ETLs.These findings provide significant insights into the role of different ETLs in enhancing QE,indicating that BST is a superior ETL that enhances both the efficiency and stability of PSCs.This study contributes to the understanding of how perovskite-structured ETLs can be used to design and optimize highly efficient and stable photovoltaic devices. 展开更多
关键词 Perovskite solar cell Electron transport layer Light management Quantum efficiency SCAPS-1D Lumerical FDTD Barium titanate
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An Improved Forest Fire Detection Model Using Audio Classification and Machine Learning
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作者 Kemahyanto Exaudi Deris Stiawan +4 位作者 Bhakti Yudho Suprapto Hanif Fakhrurroja MohdYazid Idris Tami AAlghamdi Rahmat Budiarto 《Computers, Materials & Continua》 2026年第1期2062-2085,共24页
Sudden wildfires cause significant global ecological damage.While satellite imagery has advanced early fire detection and mitigation,image-based systems face limitations including high false alarm rates,visual obstruc... Sudden wildfires cause significant global ecological damage.While satellite imagery has advanced early fire detection and mitigation,image-based systems face limitations including high false alarm rates,visual obstructions,and substantial computational demands,especially in complex forest terrains.To address these challenges,this study proposes a novel forest fire detection model utilizing audio classification and machine learning.We developed an audio-based pipeline using real-world environmental sound recordings.Sounds were converted into Mel-spectrograms and classified via a Convolutional Neural Network(CNN),enabling the capture of distinctive fire acoustic signatures(e.g.,crackling,roaring)that are minimally impacted by visual or weather conditions.Internet of Things(IoT)sound sensors were crucial for generating complex environmental parameters to optimize feature extraction.The CNN model achieved high performance in stratified 5-fold cross-validation(92.4%±1.6 accuracy,91.2%±1.8 F1-score)and on test data(94.93%accuracy,93.04%F1-score),with 98.44%precision and 88.32%recall,demonstrating reliability across environmental conditions.These results indicate that the audio-based approach not only improves detection reliability but also markedly reduces computational overhead compared to traditional image-based methods.The findings suggest that acoustic sensing integrated with machine learning offers a powerful,low-cost,and efficient solution for real-time forest fire monitoring in complex,dynamic environments. 展开更多
关键词 Audio classification convolutional neural network(CNN) environmental science forest fire detection machine learning spectrogram analysis IOT
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Fuzzy Behavior-based Control of Three Wheeled Omnidirectional Mobile Robot 被引量:8
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作者 Nacer Hacene Boubekeur Mendil 《International Journal of Automation and computing》 EI CSCD 2019年第2期163-185,共23页
In this paper, a fuzzy behavior-based approach for a three wheeled omnidirectional mobile robot(TWOMR) navigation has been proposed. The robot has to track either static or dynamic target while avoiding either static ... In this paper, a fuzzy behavior-based approach for a three wheeled omnidirectional mobile robot(TWOMR) navigation has been proposed. The robot has to track either static or dynamic target while avoiding either static or dynamic obstacles along its path. A simple controller design is adopted, and to do so, two fuzzy behaviors "Track the Target" and "Avoid Obstacles and Wall Following" are considered based on reduced rule bases(six and five rules respectively). This strategy employs a system of five ultrasonic sensors which provide the necessary information about obstacles in the environment. Simulation platform was designed to demonstrate the effectiveness of the proposed approach. 展开更多
关键词 THREE WHEELED OMNIDIRECTIONAL mobile robot (TWOMR) autonomous navigation OBSTACLE avoidance FUZZY behaviorbased control DYNAMIC target DYNAMIC environment
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Low-cost sensorless control of four-switch,brushless DC motor drive with direct back-EMF detection 被引量:4
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作者 Abolfazl HALVAEI NIASAR Abolfazl VAHEDI Hassan MOGHBELLI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第2期201-208,共8页
We propose a position sensorless control scheme for a four-switch,three-phase brushless DC motor drive,based on the zero crossing point detection of phase back-EMF voltages using newly defined error functions(EFs). Th... We propose a position sensorless control scheme for a four-switch,three-phase brushless DC motor drive,based on the zero crossing point detection of phase back-EMF voltages using newly defined error functions(EFs). The commutation in-stants are 30° after detected zero crossing points of the EFs. Developed EFs have greater magnitude rather than phase or line voltages so that the sensorless control can work at a lower speed range. Moreover,EFs have smooth transitions around zero voltage level that reduces the commutation errors. EFs are derived from the filtered terminal voltages vao and vbo of two low-pass filters,which are used to eliminate high frequency noises for calculation of the average terminal voltages. The feasibility of the proposed sensorless control is demonstrated by simulation and experimental results. 展开更多
关键词 Brushless DC motor Four-switch inverter Sensorless control Back-EMF voltage sensing DSP
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Spectral-spatial Classification of Hyperspectral Images Using Signal Subspace Identification and Edge-preserving Filter 被引量:4
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作者 Negin Alborzi Fereshteh Poorahangaryan Homayoun Beheshti 《International Journal of Automation and computing》 EI CSCD 2020年第2期222-232,共11页
Hyperspectral images in remote sensing include hundreds of spectral bands that provide valuable information for accurately identify objects.In this paper,a new method of classifying hyperspectral images using spectral... Hyperspectral images in remote sensing include hundreds of spectral bands that provide valuable information for accurately identify objects.In this paper,a new method of classifying hyperspectral images using spectral spatial information has been presented.Here,using the hyperspectral signal subspace identification(HYSIME)method which estimates the signal and noise correlation matrix and selects a subset of eigenvalues for the best representation of the signal subspace in order to minimize the mean square error,subsets from the main sample space have been extracted.After subspace extraction with the help of the HYSIME method,the edge-preserving filtering(EPF),and classification of the hyperspectral subspace using a support vector machine(SVM),results were then merged into the decision-making level using majority rule to create the spectral-spatial classifier.The simulation results showed that the spectral-spatial classifier presented leads to significant improvement in the accuracy and validity of the classification of Indiana,Pavia and Salinas hyperspectral images,such that it can classify these images with 98.79%,98.88% and 97.31% accuracy,respectively. 展开更多
关键词 HYPERSPECTRAL image remote sensing the HYPERSPECTRAL signal SUBSPACE identification(HYSIME) edge-preserving FILTER CLASSIFICATION support VECTOR machine
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Bayesian Multidimensional Scaling for Location Awareness in Hybrid-Internet of Underwater Things 被引量:4
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作者 Ruhul Amin Khalil Nasir Saeed +2 位作者 Mohammad Inayatullah Babar Tariqullah Jan Sadia Din 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第3期496-509,共14页
Localization of sensor nodes in the internet of underwater things(IoUT)is of considerable significance due to its various applications,such as navigation,data tagging,and detection of underwater objects.Therefore,in t... Localization of sensor nodes in the internet of underwater things(IoUT)is of considerable significance due to its various applications,such as navigation,data tagging,and detection of underwater objects.Therefore,in this paper,we propose a hybrid Bayesian multidimensional scaling(BMDS)based localization technique that can work on a fully hybrid IoUT network where the nodes can communicate using either optical,magnetic induction,and acoustic technologies.These communication technologies are already used for communication in the underwater environment;however,lacking localization solutions.Optical and magnetic induction communication achieves higher data rates for short communication.On the contrary,acoustic waves provide a low data rate for long-range underwater communication.The proposed method collectively uses optical,magnetic induction,and acoustic communication-based ranging to estimate the underwater sensor nodes’final locations.Moreover,we also analyze the proposed scheme by deriving the hybrid Cramer-Rao lower bound(H-CRLB).Simulation results provide a complete comparative analysis of the proposed method with the literature. 展开更多
关键词 Bayesian multidimensional scaling(BMDS) hybrid Cramer-Rao lower bound(H-CRLB) internet of underwater things(IoUT) signals of opportunity(SOA)approach
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Fuzzy-second order sliding mode control optimized by genetic algorithm applied in direct torque control of dual star induction motor 被引量:3
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作者 Ghoulemallah BOUKHALFA Sebti BELKACEM +1 位作者 Abdesselem CHIKHI Moufid BOUHENTALA 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第12期3974-3985,共12页
The direct torque control of the dual star induction motor(DTC-DSIM) using conventional PI controllers is characterized by unsatisfactory performance, such as high ripples of torque and flux, and sensitivity to parame... The direct torque control of the dual star induction motor(DTC-DSIM) using conventional PI controllers is characterized by unsatisfactory performance, such as high ripples of torque and flux, and sensitivity to parametric variations. Among the most evoked control strategies adopted in this field to overcome these drawbacks presented in classical drive, it is worth mentioning the use of the second order sliding mode control(SOSMC) based on the super twisting algorithm(STA) combined with the fuzzy logic control(FSOSMC). In order to realize the optimal control performance, the FSOSMC parameters are adjusted using an optimization algorithm based on the genetic algorithm(GA). The performances of the envisaged control scheme, called G-FSOSMC, are investigated against G-SOSMC, G-PI and BBO-FSOSMC algorithms. The proposed controller scheme is efficient in reducing the torque and flux ripples, and successfully suppresses chattering. The effects of parametric uncertainties do not affect system performance. 展开更多
关键词 double star induction machine direct torque control fuzzy second order sliding mode control genetic algorithm biogeography based optimization algorithm
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Five-phase Synchronous Reluctance Machines Equipped with a Novel Type of Fractional Slot Winding 被引量:2
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作者 S.M.Taghavi Araghi A.Kiyoumarsi B.Mirzaeian Dehkordi 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第3期264-273,共10页
Multi-phase machines are so attractive for electrical machine designers because of their valuable advantages such as high reliability and fault tolerant ability.Meanwhile,fractional slot concentrated windings(FSCW)are... Multi-phase machines are so attractive for electrical machine designers because of their valuable advantages such as high reliability and fault tolerant ability.Meanwhile,fractional slot concentrated windings(FSCW)are well known because of short end winding length,simple structure,field weakening sufficiency,fault tolerant capability and higher slot fill factor.The five-phase machines equipped with FSCW,are very good candidates for the purpose of designing motors for high reliable applications,like electric cars,major transporting buses,high speed trains and massive trucks.But,in comparison to the general distributed windings,the FSCWs contain high magnetomotive force(MMF)space harmonic contents,which cause unwanted effects on the machine ability,such as localized iron saturation and core losses.This manuscript introduces several new five-phase fractional slot winding layouts,by the means of slot shifting concept in order to design the new types of synchronous reluctance motors(SynRels).In order to examine the proposed winding’s performances,three sample machines are designed as case studies,and analytical study and finite element analysis(FEA)is used for validation. 展开更多
关键词 Finite element analysis Five-phase machine Fractional slot concentrated winding(FSCW) Machine slot/pole combination MMF harmonics Synchronous reluctance machine Winding factor
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Utilization of HEVC ChaCha20-Based Selective Encryption for Secure Telehealth Video Conferencing 被引量:2
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作者 Osama S.Faragallah Ahmed I.Sallam Hala S.El-sayed 《Computers, Materials & Continua》 SCIE EI 2022年第1期831-845,共15页
Coronavirus(COVID-19)is a contagious disease that causes exceptional effect on healthcare organizationsworldwide with dangerous impact on medical services within the hospitals.Because of the fast spread of COVID-19,th... Coronavirus(COVID-19)is a contagious disease that causes exceptional effect on healthcare organizationsworldwide with dangerous impact on medical services within the hospitals.Because of the fast spread of COVID-19,the healthcare facilities could be a big source of disease infection.So,healthcare video consultations should be used to decrease face-to-face communication between clinician and patients.Healthcare video consultations may be beneficial for some COVID-19 conditions and reduce the need for faceto-face contact with a potentially positive patient without symptoms.These conditions are like top clinicians who provide remote consultations to develop treatment methodology and follow-up remotely,patients who consult about COVID-19,and those who have mild symptoms suggestive of the COVID-19 virus.Video consultations are a supplement to,and not a substitute for,telephone consultations.It may also form part of a broader COVID-19 distance care strategy that contains computerized screening,separation of possibly infectious patients within medical services,and computerized video-intensive observing of their intensive care that helps reduce mixing.Nowadays,the spread of the COVID-19 virus helps to expand the use of video healthcare consultations because it helps to exchange experiences and remote medical consultations,save costs and health procedures used to cope with the pandemic of the COVID-19 virus,and monitor the progress of treatment plans,moment by moment from a distance with precision,clarity and ease.From this perspective,this paper introduces a high-efficiency video coding(HEVC)ChaCha20-based selective encryption(SE)scheme for secure healthcare video Consultations.The proposed HEVC ChaCha20-based SE scheme uses the ChaCha20 for encrypting the sign bits of the Discrete Cosine Transform(DCT)and Motion Vector Difference(MVD)in the HEVC entropy phase.The main achievement of HEVC ChaCha20-based SE scheme is encrypting the most sensitive video bits with keeping low delay time,fixed bit rate of the HEVC,and format compliance.Experimental tests guarantee that the proposed HEVC ChaCha20-based SE scheme can ensure the confidentiality of the healthcare video consultations which has become easy to transmit through the internet. 展开更多
关键词 TELEHEALTH HEVC cahcha20 video conferencing
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Geyser Inspired Algorithm:A New Geological-inspired Meta-heuristic for Real-parameter and Constrained Engineering Optimization 被引量:5
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作者 Mojtaba Ghasemi Mohsen Zare +3 位作者 Amir Zahedi Mohammad-Amin Akbari Seyedali Mirjalili Laith Abualigah 《Journal of Bionic Engineering》 SCIE EI CSCD 2024年第1期374-408,共35页
Over the past years,many efforts have been accomplished to achieve fast and accurate meta-heuristic algorithms to optimize a variety of real-world problems.This study presents a new optimization method based on an unu... Over the past years,many efforts have been accomplished to achieve fast and accurate meta-heuristic algorithms to optimize a variety of real-world problems.This study presents a new optimization method based on an unusual geological phenomenon in nature,named Geyser inspired Algorithm(GEA).The mathematical modeling of this geological phenomenon is carried out to have a better understanding of the optimization process.The efficiency and accuracy of GEA are verified using statistical examination and convergence rate comparison on numerous CEC 2005,CEC 2014,CEC 2017,and real-parameter benchmark functions.Moreover,GEA has been applied to several real-parameter engineering optimization problems to evaluate its effectiveness.In addition,to demonstrate the applicability and robustness of GEA,a comprehensive investigation is performed for a fair comparison with other standard optimization methods.The results demonstrate that GEA is noticeably prosperous in reaching the optimal solutions with a high convergence rate in comparison with other well-known nature-inspired algorithms,including ABC,BBO,PSO,and RCGA.Note that the source code of the GEA is publicly available at https://www.optim-app.com/projects/gea. 展开更多
关键词 Nature-inspired algorithms Real-world and engineering optimization Mathematical modeling Geyser algorithm(GEA)
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Fractional-Order Control of a Wind Turbine Using Manta Ray Foraging Optimization 被引量:2
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作者 Hegazy Rezk Mohammed Mazen Alhato +1 位作者 Mohemmed Alhaider Soufiene Bouallègue 《Computers, Materials & Continua》 SCIE EI 2021年第7期185-199,共15页
In this research paper,an improved strategy to enhance the performance of the DC-link voltage loop regulation in a Doubly Fed Induction Generator(DFIG)based wind energy system has been proposed.The proposed strategy u... In this research paper,an improved strategy to enhance the performance of the DC-link voltage loop regulation in a Doubly Fed Induction Generator(DFIG)based wind energy system has been proposed.The proposed strategy used the robust Fractional-Order(FO)Proportional-Integral(PI)control technique.The FOPI control contains a non-integer order which is preferred over the integer-order control owing to its benefits.It offers extra flexibility in design and demonstrates superior outcomes such as high robustness and effectiveness.The optimal gains of the FOPI controller have been determined using a recent Manta Ray Foraging Optimization(MRFO)algorithm.During the optimization process,the FOPI controller’s parameters are assigned to be the decision variables whereas the objective function is the error racking that to be minimized.To prove the superiority of the MRFO algorithm,an empirical comparison study with the homologous particle swarm optimization and genetic algorithm is achieved.The obtained results proved the superiority of the introduced strategy in tracking and control performances against various conditions such as voltage dips and wind speed variation. 展开更多
关键词 Renewable energy MODELING wind turbine doubly fed induction generator fractional order control manta ray foraging optimization
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Damping controller design based on FO-PID-EMA in VSC HVDC system to improve stability of hybrid power system 被引量:2
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作者 Nima SHAFAGHATIAN Arvin KIANI +2 位作者 Naser TAHERI Zahra RAHIMKHANI Seyyed Saeed MASOUMI 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期403-417,共15页
Wind energy sources have different structures and functions from conventional power plants in the power system.These resources can affect the exchange of active and reactive power of the network.Therefore,power system... Wind energy sources have different structures and functions from conventional power plants in the power system.These resources can affect the exchange of active and reactive power of the network.Therefore,power system stability will be affected by the performance of wind power plants,especially in the event of a fault.In this paper,the improvement of the dynamic stability in power system equipped by wind farm is examined through the supplementary controller design in the high voltage direct current(HVDC)based on voltage source converter(VSC)transmission system.In this regard,impacts of the VSC HVDC system and wind farm on the improvement of system stability are considered.Also,an algorithm based on controllability(observability)concept is proposed to select most appropriate and effective coupling between inputs-outputs(IO)signals of system in different work conditions.The selected coupling is used to apply damping controller signal.Finally,a fractional order PID controller(FO-PID)based on exchange market algorithm(EMA)is designed as damping controller.The analysis of the results shows that the wind farm does not directly contribute to the improvement of the dynamic stability of power system.However,it can increase the controllability of the oscillatory mode and improve the performance of the supplementary controller. 展开更多
关键词 hybrid power system high voltage direct current based on voltage source converter(VSC HVDC) fractional order PID(FO-PID)damping controller exchange market algorithm
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Grey Wolf Optimization Based Tuning of Terminal Sliding Mode Controllers for a Quadrotor 被引量:2
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作者 Rabii Fessi Hegazy Rezk Soufiene Bouallègue 《Computers, Materials & Continua》 SCIE EI 2021年第8期2265-2282,共18页
The research on Unmanned Aerial Vehicles(UAV)has intensified considerably thanks to the recent growth in the fields of advanced automatic control,artificial intelligence,and miniaturization.In this paper,a Grey Wolf O... The research on Unmanned Aerial Vehicles(UAV)has intensified considerably thanks to the recent growth in the fields of advanced automatic control,artificial intelligence,and miniaturization.In this paper,a Grey Wolf Optimization(GWO)algorithm is proposed and successfully applied to tune all effective parameters of Fast Terminal Sliding Mode(FTSM)controllers for a quadrotor UAV.A full control scheme is first established to deal with the coupled and underactuated dynamics of the drone.Controllers for altitude,attitude,and position dynamics become separately designed and tuned.To work around the repetitive and time-consuming trial-error-based procedures,all FTSM controllers’parameters for only altitude and attitude dynamics are systematically tuned thanks to the proposed GWO metaheuristic.Such a hard and complex tuning task is formulated as a nonlinear optimization problem under operational constraints.The performance and robustness of the GWO-based control strategy are compared to those based on homologous metaheuristics and standard terminal sliding mode approaches.Numerical simulations are carried out to show the effectiveness and superiority of the proposed GWO-tuned FTSM controllers for the altitude and attitude dynamics’stabilization and tracking.Nonparametric statistical analyses revealed that the GWO algorithm is more competitive with high performance in terms of fastness,non-premature convergence,and research exploration/exploitation capabilities. 展开更多
关键词 QUADROTOR cascade control fast terminal sliding mode control grey wolf optimizer nonparametric Friedman analysis
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Photovoltaic Models Parameters Estimation Based on Weighted Mean of Vectors 被引量:1
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作者 Mohamed Elnagi Salah Kamel +1 位作者 Abdelhady Ramadan Mohamed F.Elnaggar 《Computers, Materials & Continua》 SCIE EI 2023年第3期5229-5250,共22页
Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy source.This is evident in the advancement of scientific research aimed at improving solar cell performance.Due to the ... Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy source.This is evident in the advancement of scientific research aimed at improving solar cell performance.Due to the non-linear nature of the photovoltaic cell,modeling solar cells and extracting their parameters is one of the most important challenges in this discipline.As a result,the use of optimization algorithms to solve this problem is expanding and evolving at a rapid rate.In this paper,a weIghted meaN oF vectOrs algorithm(INFO)that calculates the weighted mean for a set of vectors in the search space has been applied to estimate the parameters of solar cells in an efficient and precise way.In each generation,the INFO utilizes three operations to update the vectors’locations:updating rules,vector merging,and local search.The INFO is applied to estimate the parameters of static models such as single and double diodes,as well as dynamic models such as integral and fractional models.The outcomes of all applications are examined and compared to several recent algorithms.As well as the results are evaluated through statistical analysis.The results analyzed supported the proposed algorithm’s efficiency,accuracy,and durability when compared to recent optimization algorithms. 展开更多
关键词 Photovoltaic(PV)modules weIghted meaN oF vectOrs algorithm(INFO) renewable energy static PV models dynamic PV models solar energy
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Design of a Novel THz Modulator for B5G Communication 被引量:1
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作者 Omar A.Saraereh 《Computers, Materials & Continua》 SCIE EI 2022年第10期1055-1066,共12页
Wireless data traffic has expanded at a rate that reminds us of Moore’s prediction for integrated circuits in recent years,necessitating ongoing attempts to supply wireless systems with ever-larger data rates in the ... Wireless data traffic has expanded at a rate that reminds us of Moore’s prediction for integrated circuits in recent years,necessitating ongoing attempts to supply wireless systems with ever-larger data rates in the near future,despite the under-deployment of 5G networks.Terahertz(THz)communication has been considered a viable response to communication blackout due to the rapid development of THz technology and sensors.THz communication has a high frequency,which allows for better penetration.It is a fast expanding and evolving industry,driven by an increase in wireless traffic volume and data transfer speeds.A THz modulator based on a hybrid metasurface was devised and built in this work.The device’s modulation capabilities were modelled and proved experimentally.The electrolyte is an ion-gel medium implanted between graphene and metasurface,and the active material is graphene.On the metasurface,the interaction between the THz wave and graphene is improved.Additionally,an external bias voltage was employed to actively regulate the THz waves by tuning the electrical conductivity of graphene.The results show that with a minimal bias voltage,the device can achieve a modulation depth of up to 73%at the resonant frequency.Furthermore,during the modulation process,the resonance frequency remains almost constant.As a result,the proposed gadget offers a unique tool for substantial THz amplitude modulation at low voltages. 展开更多
关键词 Terahertz communication MODULATOR metasurface GRAPHENE
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Optimal Selection of Hybrid Renewable Energy System Using Multi-Criteria Decision-Making Algorithms 被引量:1
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作者 Hegazy Rezk Irik Z.Mukhametzyanov +1 位作者 Mujahed Al-Dhaifallah Hamdy A.Ziedan 《Computers, Materials & Continua》 SCIE EI 2021年第8期2001-2027,共27页
Several models of multi-criteria decision-making(MCDM)have identified the optimal alternative electrical energy sources to supply certain load in an isolated region in Al-Minya City,Egypt.The load demand consists of w... Several models of multi-criteria decision-making(MCDM)have identified the optimal alternative electrical energy sources to supply certain load in an isolated region in Al-Minya City,Egypt.The load demand consists of water pumping system with a water desalination unit.Various options containing three different power sources:only DG,PV-B system,and hybrid PV-DG-B,two different sizes of reverse osmosis(RO)units;RO-250 and RO-500,two strategies of energy management;load following(LF)and cycle charging(CC),and two sizes of DG;5 and 10 kW were taken into account.Eight attributes,including operating cost,renewable fraction,initial cost,the cost of energy,excess energy,unmet load,breakeven grid extension distance,and the amount of CO_(2),were used during the evaluation process.To estimate these parameters,HOMER®software was employed to perform both the simulation and optimization process.Four different weight estimation methods were considered;no priority of criteria,based on a pairwise comparisons matrix of the criteria,CRITIC-method,and entropy-based method.The main findings(output results)confirmed that the optimal option for the case study was hybrid PV-DG-B with the following specification:5 kW DG,RO-500,and load following control strategy.Under this condition,the annual operating cost and initial costs were$5546 and$161022,respectively,whereas the cost of energy was 0.077$/kWh.The excess energy and unmet loads were 40998 and 2371 kWh,respectively.The breakeven grid extension distance and the amount of CO_(2) were 3.31 km and 5171 kg per year,respectively.Compared with DG only,the amount of CO_(2) has been sharply reduced by 113939 kg per year. 展开更多
关键词 Al-Minya city(Egypt) energy efficiency multi-criteria decision-making OPTIMIZATION renewable energy reverse osmosis units
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Synthesis of Green Adhesive with Tannin Extracted from Eucalyptus Bark for Potential Use in Wood Composites 被引量:1
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作者 Medjda Amari Kamel Khimeche +2 位作者 Abdelkader Hima Redouane Chebout Abderahmane Mezroua 《Journal of Renewable Materials》 SCIE EI 2021年第3期463-475,共13页
Recently,the exploitation of renewable plant resources in the formulation of adhesives is very promising for their availability at low coast,as well as their richness in biomolecules such as polyphenols.In this way,ma... Recently,the exploitation of renewable plant resources in the formulation of adhesives is very promising for their availability at low coast,as well as their richness in biomolecules such as polyphenols.In this way,many research studies tannins extracted from different sources such as mimosa,quebracho,and pine have been the subject of very satisfactory recent studies.In this paper,a new complete characterization of the tannins extracted from the bark of eucalyptus globulus harvested from two regions in Algeria was achieved.The structural characterization enabled us to confirm the richness in condensed tannins,particularly in procyanidin and prodelphinidin units.The most reactive tannins obtained during extraction at 70℃(yield:27.1%)have a Stiasny number of 75.92%.This extract was used for the formulation of adhesives(tannin/hexamine).The thermal characterizaction of the adhesives showed higher stability for the tannin formulation of eucalyptus/hexamine as well as an excellent mechanical performance with a MOE of 2807 MPa at 180℃and shear strength of 689.4 N/mm^(2). 展开更多
关键词 E.globulus TANNINS RESIN adhesives FTIR NMR
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