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Indirect Vector Control of Linear Induction Motors Using Space Vector Pulse Width Modulation

Computers, Materials & Continua 2023年第3期74卷 6263-6287页

作者： Arjmand Khaliq Syed Abdul Rahman Kashif Fahad Ahmad Muhammad Anwar Qaisar Shaheen rizwan akhtar Muhammad Arif Shah Abdelzahir Abdelmaboud Electrical Engineering Department University of Engineering and TechnologyLahore54700Pakistan Department of Basic Sciences Deanship of Common First YearJouf UniversitySakakaAljouf72341Saudi Arabia Department of Information Science Division of Science and TechnologyUniversity of EducationLahore54000Pakistan Department of Computer Science and Information Technology The Islamia University of BahawalpurRahim Yar Khan Sub CampusPakistan Department of IT and Computer Science Pak-Austria Fachhochschule Institute of Applied Sciences and TechnologyHaripurPakistan Department of Information Systems King Khalid UniversityMuhayel Aseer61913Saudi Arabia

Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance *** trend promotes the development of precise and efficient control schemes for individual *** research aims to present a novel framework for speed and thrust force control of LIM using space vector pulse width modulation(SVPWM)*** framework under consideration is developed in four *** begin,MATLAB Simulink was used to develop a detailed mathematical and electromechanical *** research presents a modified SVPWM inverter control *** tuning the proportional-integral(PI)controller with a transfer function,optimized values for the PI controller are *** the subsystems mentioned above are integrated to create a robust simulation of the LIM’s precise speed and thrust force control *** reference speed values were chosen to evaluate the performance of the respective system,and the developed system’s response was verified using various data *** the low-speed range,a reference value of 10m/s is used,while a reference value of 100 m/s is used for the high-speed *** speed output response indicates that themotor reached reference speed in amatter of seconds,as the delay time is between 8 and 10 *** maximum amplitude of thrust achieved is less than 400N,demonstrating the controller’s capability to control a high-speed LIM with minimal thrust *** to the controlled speed range,the developed system is highly recommended for low-speed and high-speed and heavy-duty traction applications.

关键词： Space vector pulse width modulation linear induction motor proportional-integral controller indirect vector control electromechanical dynamic modeling

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Diabetic Retinopathy Severity Classification Using Data Fusion and Ensemble Transfer Learning

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Journal of Software Engineering and Applications 2025年第1期18卷 1-23页

作者： Shabib Aftab Samia akhtar Department of Computer Science Virtual University of Pakistan Lahore Pakistan

Diabetic retinopathy is a serious concern for people dealing with diabetes. Detecting diabetic retinopathy poses significant challenges, requiring skilled professionals, extensive manual image processing, and considerable time investment. Fortunately, the integration of deep learning and transfer learning offers invaluable assistance to medical practitioners. This study introduces an ensemble classification framework to detect and grade diabetic retinopathy into 5 classes leveraging the concepts of transfer learning and data fusion. It utilizes three benchmark datasets on diabetic retinopathy: APTOS 2019, IDRiD, and Messidor-2. Initially, these datasets are merged, resulting in a total of 5922 fundus images. Then this fused dataset undergoes pre-processing. Firstly, the images are cropped to remove unwanted regions. Then, Contrast Limited Adaptive Histogram Equalization is applied to improve image quality and fine details. To tackle class imbalance issues, Synthetic Minority Over Sampling technique is employed. Additionally, data augmentation techniques such as flipping, rotation, and zooming are used to increase dataset diversity. The dataset is split into training, validation, and testing sets at a ratio of 70:10:20. For classification, three pre-trained CNN models, EfficientNetB2, DenseNet121, and ResNet50, are fine-tuned. After these models are trained, an ensemble model is constructed by averaging the predictions of each model. Results show that the ensemble model achieved the highest test accuracy of 96.96% in grading diabetic retinopathy into 5 classes outperforming the individual pre-trained models. Furthermore, the ensemble model’s performance is compared with previously published approaches where this model demonstrated superior result.

关键词： Diabetic Retinopathy Fundus Images CLAHE Augmentation Optimizer

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Fine mapping and identification of CaTTG1,a candidate gene that regulates the hypocotyl anthocyanin accumulation in Capsicum annuum

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Horticultural Plant Journal 2025年第1期11卷 264-274页

作者： Jin Wang Yao Dai Luzhao Pan Ying Chen Li Dai Yanqing Ma Xiaoxun Zhou Wu Miao Muhammad rizwan Hamid Xuexiao Zou Feng Liu Cheng Xiong Engineering Research Center for Germplasm Innovation and New Varieties Breeding of Horticultural Crops Key Laboratory for Vegetable Biology of Hunan ProvinceCollege of HorticultureHunan Agricultural UniversityChangshaHunan 410000China Hunan Xiangyan Seed Industry Co. LTDChangshaHunan 410000China

Pepper(Capsicum annuum L.)is a typical self-pollinating crop with obvious heterosis in ***,the use of morphological markers during the pepper seedling stage is crucial for pepper *** color of hypocotyl is widely used as a phenotypic marker in crossing studies of *** accessions generally have purple hypocotyls,which are mainly due to the anthocyanin accumulation in seedlings,and green hypocotyls are rarely observed in *** we reported the characterization of a green hypocotyl mutant of pepper,Cha1,which was identified from a pepper ethyl methanesulfonate(EMS)mutant *** mapping revealed that the causal gene,CaTTG1,belonging to the WD40 repeat family,controlled the green hypocotyl phenotype of the ***-induced gene silencing(VIGS)confirmed that CaTTG1 regulated anthocyanin ***-seq data showed that expression of structural genes CaDFR,CaANS,and CaUF3GT in the anthocyanin biosynthetic pathway was significantly decreased in Cha1 compared to the wild *** two-hybrid(Y2H)experiments also confirmed that CaTTG1 activated the synthesis of anthocyanin structural genes by forming a MBW complex with CaAN1 and *** summary,this study provided a green hypocotyl mutant of pepper,and the Kompetitive Allele Specific PCR(KASP)marker developed based on the mutation site of the underlying gene would be helpful for pepper breeding.

关键词： Pepper CaTTG1 Anthocyanin Hypocotyl color Fine-mapping

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Tunable and wideband high-performance rare earth-doped Ni-Mg-Cu-Zn nano ferrite-based meta-absorbers for C-band application

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Journal of Rare Earths 2025年第1期43卷 124-132,I0005页

作者： Majid Niaz akhtar Magbool Alelyani Fatimah Mohammed AAlzahrani Abdullah Almohammedi Sabih Qamar MABaqir MIrfan Muhammad Azhar Khan Kheir SAlbarkaty ZAAlrowaili MSAl-Buriahi Institute of Physics The Islamia University of Bahawalpur63100BahawalpurPakistan Department of Radiological Sciences College of Applied Medical ScienceKing Khalid University61421bhaSaudi Arabia Department of Chemistry College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabi Department of Physics Faculty of ScienceIslamic University of Madinah42352.Saudi Arabia Department of Chemical Engineering Muhammad Nawaz Sharif University of Engineering and Technology(MNSUET)60000MultanPakistan Department of Electrical and Computer Engineering COMSATS University IslamabadSahiwal Campus57000Pakistan Department of Physics Umm Al-Qura UniversityMakkah24382Saudi Arabia Department of Physics College of ScienceJouf UniversityP.O.Box:201474331SakakaSoudi Arabia Department of Physics Sakarya University6900SakaryaTurkey

Due to advanced technology,electromagnet interference and dissipation problems in the electronic and portable devices at GHz range are increasing *** absorbing materials with outstanding electromagnetic properties,wide bandwidth,and strong absorption are highly *** present investigation deals with the preparation of Ni-Mg-Cu-Zn(NMCZ)substituted nano ferrites with composition of Ni_(0.3)Mg_(0.2)Cu_(0.3)Zn_(0.2)X_(0.02)Fe_(1.98)O_(4)(X=Nd,Ho,Pr,Gd,Yb).X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),a vibratory sample magnetometer(VSM),and a Vector network analyzer(VNA)were used to investigate these rare earth-doped nanocrystalline ferrites'*** reveals the single spinel phase structure in all Ni-Mg-Cu-Zn *** spectroscopy shows the presence of tetrahedral and octahedral bands of spinel *** images reveal the lowest agglomeration for the Ho-doped NMCZ nano-spinel ferrites *** images show the hexagon shapes of the Yb-and Nd-doped NMCZ ***-doped NMCZ ferrites show more coercivity than other rare earth metals substituted NMCZ nanocrystalline *** analysis was used to calculate the magnetic features like initial permeability,magnetic anisotropy constant,remanence,coercivity,and magnetic ***-frequency switching field distributions(SFD)analyses were also *** characteristics such as losses,permittivity,modulus,Q,ac conductivity,and impedance of the Nd^(-),Ho^(-),Pr^(-),Gd^(-),Yb-doped Ni-Mg-Cu-Zn ferrites were *** minimum reflection loss(-57.3 dB)is found at 1.4 GHz for Pr-doped Ni-Mg-Cu-Zn ferrite ***,the reflection loss(RL)of-53.9 dB at 2.9 GHz is observed for Ho-doped Ni-Mg-Cu-Zn ferrite *** magnetization,low coercivity,outstanding magnetodielectric,and absorption properties of theNd^(-),Ho^(-),Pr^(-),Gd^(-)and Yb^(-)doped Ni-Mg

关键词： Rare earths Reflection loss Cubic phase Magnetodielectric Ni-Mg-Cu-Zn(NMCZ)meta-absorber

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Evaluating Wharton’s jelly-derived stem cell therapy in autism:Insights from a case study

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World Journal of Methodology 2025年第2期15卷 174-176页

作者： Muzamil akhtar Abdulqadir J Nashwan College of Medicine Gujranwala Medical CollegeGujranwala 52250PunjabPakistan Department of Nursing and Midwifery Research Hamad Medical CorporationDoha 3050Qatar

Autism spectrum disorder(ASD)is a complex neurodevelopmental disorder affecting over 2%of the global population,marked by social communication deficits and repetitive *** et al explored the efficacy and safety of Wharton’s jelly-derived mesenchymal stem cell(WJ-MSC)therapy in a 4-year-old child with *** the childhood autism rating scale and Denver II develop-mental screening test,significant improvements were seen after six WJ-MSC sessions,with no adverse events over 2 *** promising results,the study’s single-case design limits ***,multi-center trials are needed to validate the findings and assess long-term effects of WJ-MSC therapy in ASD.

关键词： Autism spectrum disorder Stem cell therapy Neuroinflammation Neuro-developmental disorders Wharton jelly derived mesenchymal stem cell

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Occurrence Models of Movable Fluid in Lacustrine Sandstone Reservoir of Chang 7 Member in the Heshui Block,Ordos Basin,China

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Journal of Earth Science 2025年第1期36卷 57-74页

作者： Qibiao Zang Chenglin Liu rizwan Sarwar Awan Xiya Yang Zhendong Lu Guoxiong Li Yuping Wu Dehao Feng State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing102249China College of Geosciences China University of PetroleumBeijing102249China

The Chang 7 sandstone is characterized by complex micro-pore structures,strong heterogeneity,and differential fluid *** characteristics result in low oil *** this paper,various techniques,including high-pressure mercury intrusion,nuclear magnetic resonance,scanning electron microscope,thin section,and X-ray diffraction,are employed to quantitatively evaluate the occurrence characteristics and influencing factors of movable fluids in Chang 7 sandstone reservoirs from the Heshui Block with different fractal *** show that the dominant sandstone type is feldspar lithic fragment *** 7 reservoir has been divided into three types(typesⅠ,Ⅱ,andⅢ)based on capillary pressure curves and pore structure *** reservoirs are characterized by various fractal structures and different movable fluids *** possible factors affecting the movable fluid distribution are analyzed,including physical properties,pore structure,pore size distribution,mineral content,and *** fluid saturation is positively correlated with physical properties,weighted average pore-throat radius,median pore-throat radius,final residual mercury saturation,and maximum mercury withdrawal *** contrast,it is negatively correlated with displacement pressure and has no obvious correlation with the sorting ***-and submicron-scale pores are beneficial to the movable fluid occurrence,while nano-scale pores are vice *** influence of mineral content on movable fluid occurrence varies with mineral *** is conducive to the movable fluid occurrence in submicron-scale pores,while carbonate cementation inhibits the movable fluid occurrence in submicron-scale *** inhibition of clay on the movable fluid occurrence is mainly reflected in submicron-and nano-scale pores and varies with clay mineral *** influence of heterogeneity on the movable fluid occurrence is mainly reflected in submicro

关键词： movable fluid sandstone reservoir fractal dimension nuclear magnetic resonance Ordos Basin

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Analysis of transverse momentum spectra of protons,deuterons,and tritons in symmetric heavy-ion collisions at√S_(NN)=200 GeV at the RHIC

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Chinese Physics C 2025年第1期49卷 223-237页

作者： Waqas Ahmad Ihsan Ullah Ali Zaman Imran Khan akhtar Iqbal Abdul Qudus Sana Ullah Naseeb Ullah Muhammad Ramzan Department of Physics University of Science and TechnologyBannuKP28100 Pakistan Department of Physics COMSATS University IslamabadIslamabadPakistan Department of Physics The University of Lakki MarwatLakki MarwatKhyber PukhtunkhwaPakistan Department of Physics Govt.Degree CollegeSarai NaorangKhyber PukhtunkhwaPakistan

The blast wave model with Tsallis statistics is used to analyze the transverse momentum spectra of protons(p),deuterons(d),and tritons(t)in√S_(NN)=200 GeV gold-gold(Au-Au)collisions at the RHIC in various centrality *** particular transverse momentum ranges,the model results closely match experimental data from the PHENIX(p)and STAR(d and t)*** data are compared with those of protons obtained in Cu+Cu collisions and deuterons and tritons in Ru+Ru collisions at a center of mass energy of 200 GeV from the STAR *** spectra are used to derive the kinetic freeze-out temperatures,transverse flow velocities,and freeze-out *** to the findings,the kinetic freeze-out temperature increases from the central to peripheral *** this transition,the transverse flow velocity and freeze-out volume both *** the collisions of both collaborations,this study reveals mass-dependent kinetic freeze-out temperature and differential volume ***,the non-extensivity parameter q decreases with increasing centrality of the studied heavy-ion collisions,and heavier mass particles have smaller values of q,which implies higher degrees of thermalization and equilibrium in more central collisions and for heavier particles.

关键词： transverse momentum temperature Au+Au Cu+Cu freeze-out STAR collisions LHC Pb+Pb

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Optimization and Sizing for Propulsion System of Liquid Rocket Using Genetic Algorithm

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Chinese Journal of Aeronautics 2007年第1期20卷 40-46页

作者： Saqlain akhtar School of Astronautics Beijing University of Aeronautics and Astronautics

Flight vehicle conceptual design appears to be a promising area for application of the Genetic Algorithm （GA） as an approach to help to automate part of the design process. This computational research effort strives to develop a propulsion system design strategy for liquid rocket to optimize take-off mass, satisfying the mission range under the constraint of axial overload. The method by which this process is accomplished by using GA as optimizer is outlined in this paper. Convergence of GA is improved by introducing initial population based on Design of Experiments Technique.

关键词： liquid rocket propulsion system genetic algorithm design of experiments

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Pressureless infiltration of Si_3N_4 preforms with an Al-2wt%Mg alloy

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Journal of University of Science and Technology Beijing 2005年第4期12卷 351-356页

作者： akhtar Farid Materials Science and Engineering School

The pressureless infiltration process to synthesize a silicon nitride composite was investigated. An Al-2wt%Mg alloy was infiltrated into silicon nitride preforms in the atmosphere of nitrogen. It is possible to infiltrate the Al-2wt%Mg alloy in silicon nitride preforms, The growth of the composite with useful thickness was facilitated by the presence of magnesium powder at the interface and by flowing nitrogen. The microstructure of the Si3N4-Al composite has been characterized using scanning electron microscope. During the infiltration of Si3N4 preforms, Si3N4 reacted with aluminium to form silicon and AIN. The silicon produced during the growth consumed in the formation of MgSiAIO, MgSiAlN and Al3.27Si0.47 type phases. The growth of the composite was found to proceed in two ways, depending on the oxide content in the initial preforms, First, less oxide content preforms gave rise to MgAlSiO and MgAlSiN type phases after infiltration. Second, more oxide content preforms gave rise to AlN-Al2O3 solid solution phase （AlON）, The AlON phase was only present in the composite, containing 10% aluminium in the silicon nitride preforms before infiltration.

关键词： Si3N4 composite infiltration AlON AlN-Al2O3 solid solution

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Effect of fineness of ash on pozzolanic properties and acid resistance of sugarcane bagasse ash replaced cement mortars

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Frontiers of Structural and Civil Engineering 2022年第10期16卷 1287-1300页

作者： Shan E ALI rizwan AZAM Muhammad rizwan RIAZ Mohamed ZAWAM Department of Civil Engineering University of Engineering&Technology LahoreLahore 54890Pakistan Faculty of Engineering Cairo UniversityCairo 12613Egypt

This paper addresses the potential use of Sugar Cane Bagasse Ash(SCBA)as a pozzolanic material for partial cement replacement in concrete *** mortars containing SCBA having five different particle size distributions at a replacement rate of 20%by weight were used to study the chemical and physical pozzolanic properties of *** durability of SCBA replaced mortars was also *** with 0%retained on sieve No.325 was used to replace 20%by weight of cement and create mortar specimens that were subjected to sulfuric acid attack of varying concentrations(1%–3%by weight of water).The tested samples were observed to check visual distortion,mass loss,and compressive strength loss at 1,7,14,28,and 56 d of acidic exposure,and the results were compared to those for the control sample,that was lime water cured,at the same *** SCBA sets were found to meet the requirements for pozzolan class N specified by ASTM C *** containing SCBA with 0%or 15%retention produced better compressive strength than the control mortars after 28 ***,X-ray fluorescence and X-ray diffraction analysis showed that the SCBA had favorable chemical properties for a pozzolanic ***,SCBA replaced samples at all ages showed improved resistance against acidic attack relative to that of the control *** deterioration was seen for 3%concentrated *** study’s findings demonstrated that SCBA with an appropriate fineness could be used as a pozzolanic material,consistently with ASTM C 618.

关键词： durability cement replacement sugarcane bagasse ash fineness of ash pozzolanic properties mortar acid resistance

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