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Experimental and numerical study of effecting core configurations on the static and dynamic behavior of honeycomb plate with aluminum material

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Defence Technology（防务技术） 2024年第9期39卷 177-192页

作者： Nehad Abid allah Hamza Fatima Mohammed K.al-Fatlwe Muna ali Talib Engineering College Al-Qasim Green University51013BabylonIraq Engineering Technical College of al-Najaf Al-Furat Al-Awsat Technical University(ATU)Najaf54003Iraq

The sandwich panel incorporated a honeycomb core,a widely utilized composite structure recognized as a fundamental classification of composite *** a core resembling a honeycomb,possessing thickness and softness,and is flank by rigid face sheets that sandwich various shapes and *** paper presents an examination of the static and dynamic analysis of lightweight plates made of aluminum honeycomb sandwich *** sandwich plate samples are 300 mm long,and 300 mm wide,the heights of the core have been varied at four values ranging from 10 to 25 *** honeycomb core is manufactured from aluminum material by using a novel technique namely resistance spot welding(RSW)instead of using adhesive material,which is often used when an industrial flaw is *** optimization based on response surface methodology(RSM)and design of experiment software(DOE)was used to verify the current work.A theoretical examination of the crashworthiness behavior(maximum bending load,maximum deflection)and vibration attributes(natural frequency,damping ratio,transient temporal response)of honeycomb sandwich panels with different design parameters was also carried *** addition,the finite element method-based ANSYS software was used to confirm the theoretical *** findings of the present work showed that the relationship between the natural frequency,core height,and cell size is *** contrast,the relationship between the natural frequency and the thickness of the cell wall is ***,the damping ratio is inversely proportional to the core height and cell size but directly proportional to the thickness of the cell *** study indicates that altering the core height within 10-25 mm leads to a significant increase of 82%in the natural frequency and a notable decrease of 49%in the damping *** findings are based on a specific cell size value of 0.01 m and a cell wall thickness of 0.001 ***,the results indicate

关键词： Honeycomb Load Transient response Free vibration Natural frequency

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Parametric investigation of railway fastenings into the formation and mitigation of short pitch corrugation

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Railway Engineering Science 2024年第3期32卷 286-306页

作者： Pan Zhang Shaoguang Li Rolf Dollevoet Zili Li Section of Railway Engineering Delft University of TechnologyStevinweg 12628 CN Delftthe Netherlands

Short pitch corrugation has been a problem for railways worldwide over one *** this paper,a parametric investigation of fastenings is conducted to understand the corrugation formation mechanism and gain insights into corrugation mitigation.A three-dimensional finite element vehicle-track dynamic interaction model is employed,which considers the coupling between the structural dynamics and the contact mechanics,while the damage mechanism is assumed to be differential *** fastening models with different configurations,boundary conditions,and parameters of stiffness and damping are built up and *** models may represent different service stages of fastenings in the ***,the effect of train speeds on corrugation features is *** results indicate:(1)Fastening parameters and modelling play an important role in corrugation formation.(2)The fastening longitudinal constraint to the rail is the major factor that determines the corrugation *** fastening vertical and lateral constraints influence corrugation features in terms of spatial distribution and wavelength components.(3)The strengthening of fastening constraints in the longitudinal dimension helps to mitigate ***,the inner fastening constraint in the lateral direction is necessary for corrugation alleviation.(4)The increase in fastening longitudinal stiffness and damping can reduce the vibration amplitudes of longitudinal compression modes and thus reduce the track corrugation *** simulation in this work can well explain the field corrugation in terms of the occurrence possibility and major wavelength *** can also explain the field data with respect to the small variation between the corrugation wavelength and train speed,which is caused by frequency selection and jump between rail longitudinal compression modes.

关键词： Short pitch corrugation Fastening modelling and parameters Corrugation formation and mitigation Rail longitudinal compression modes Finite element vehicle-track interaction model

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Improved Dwarf Mongoose Optimization algorithm for Feature Selection:Application in Software Fault Prediction Datasets

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Journal of Bionic Engineering 2024年第4期21卷 2000-2033页

作者： Abdelaziz I.Hammouri Mohammed A.Awadallah Malik Sh.Braik Mohammed Azmi al-Betar Majdi Beseiso Department of Computer Science Al-Balqa Applied UniversityAl-Salt19117Jordan Department of Scientific Research and Graduate Studies University of Prince Mugrin42241MedinaSaudi Arabia Department of Computer Science Al-Aqsa UniversityGaza4051Palestine Artificial Intelligence Research Center(AIRC) Ajman UniversityAjmanUnited Arab Emirates Department of Information Technology Al-Huson University CollegeAl-Balqa Applied UniversityAl-HusonIrbid21110Jordan

Feature selection(FS)plays a crucial role in pre-processing machine learning datasets,as it eliminates redundant features to improve classification accuracy and reduce computational *** paper presents an enhanced approach to FS for software fault prediction,specifically by enhancing the binary dwarf mongoose optimization(BDMO)algorithm with a crossover mechanism and a modified positioning updating *** proposed approach,termed iBDMOcr,aims to fortify exploration capability,promote population diversity,and lastly improve the wrapper-based FS process for software fault prediction *** gained superb performance compared to other well-esteemed optimization methods across 17 benchmark *** ranked first in 11 out of 17 datasets in terms of average classification ***,iBDMOcr outperformed other methods in terms of average fitness values and number of selected features across all *** findings demonstrate the effectiveness of iBDMOcr in addressing FS problems in software fault prediction,leading to more accurate and efficient models.

关键词： Dwarf mongoose optimization algorithm Optimization Feature selection Classification

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Intelligent algorithm-based maximum power point tracker for an off-grid photovoltaic-powered direct-current irrigation system

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Clean Energy 2024年第3期8卷 48-61页

作者： Hussain Attia Maen Takruri ali al-Ataby Department of Electrical Electronics and Communications EngineeringAmerican University of Ras Al KhaimahRas Al KhaimahUnited Arab Emirates

This research aims to enhance the performance of photovoltaic(PV)systems on a 2-fold ***,it introduces an advanced deep artificial neural network algorithm for accurate and fast maximum power point tracking,ensuring optimal extraction of electrical power from PV ***,it proposes the use of 96-V,2.98-kW direct-current(DC)water pumps for farm irrigation,aiming to improve efficiency,reduce cost and complexity,and overcome challenges associated with connecting faraway farm irrigation systems to the utility *** this study,it has been demonstrated that the use of DC pumps greatly improves system performance and efficiency by eliminating the need for isolation transformers,power passive filters and inverters,therefore simplifying the architecture of the *** efficacy of the proposed methodology is confirmed by MATLAB®/Simulink®simulation results,whereby the proposed algorithm attains a mean squared error of 6.5705×10^(-5)and a system efficiency approaching 99.8%,ensuring a steady voltage under varying load conditions.

关键词： artificial neural network photovoltaic arrays maximum power point tracking buck converter direct-current irrigation systems MATLAB/Simulink

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Virtual Transmission Solution Based on Battery Energy Storage Systems to Boost Transmission Capacity

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 466-474页

作者： Matías Agüero Jaime Peralta Eugenio Quintana Victor Velar Anton Stepanov Hossein Ashourian Jean Mahseredjian Roberto Cárdenas Coordinador Eléctrico Nacional SantiagoChile PGSTech Montreal Canada Ecole Polytechnique de Montréal Montréal Canada University of Chile Santiago Chile IEEE

The increasing penetration of variable renewable energy(VRE)generation along with the decommissioning of conventional power plants in Chile,has raised several operational challenges in the Chilean National Power Grid(NPG),including transmission congestion and VRE *** mitigate these limitations,an innovative virtual transmission solution based on battery energy storage systems(BESSs),known as grid booster(GB),has been proposed to increase the capacity of the main 500 kV corridor of the *** paper analyzes the dynamic performance of the GB using a wide-area electromagnetic transient(EMT)model of the *** GB project,composed of two 500 MVA BESS units at each extreme of the 500 kV corridor,allows increasing the transmission capacity for 15 min during N-1 contingencies,overcoming transmission limitations under normal operation conditions while maintaining system stability during *** dynamic behavior of the GB is also analyzed to control power flow as well as voltage *** results show that the GB is an effective solution to allow greater penetration of VRE generation while maintaining system stability in the NPG.

关键词： Battery energy storage system(BESS) grid booster transient stability voltage stability electromagnetic transient(EMT)

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Heat Transfer Enhancement of the Absorber Tube in a Parabolic Trough Solar Collector through the Insertion of Novel Cylindrical Turbulators

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1279-1297页

作者： Yasser Jebbar Fadhil Fluiful Wisam Khudhayer Department of Electrical Techniques Al-Mussaib Technical InstituteAl-Furat Al-Awsat Technical UniversityBabilIraq Department of Physics Collage of ScienceUniversity of KerbalaKarbalaIraq Department of Energy Engineering Collage of Engineering/Al-MusayabUniversity of BabylonBabilIraq

This study includes an experimental and numerical analysis of the performances of a parabolic trough collector(PTC)with and without cylindrical *** PTC is designed with dimensions of 2.00 m in length and 1.00 m in *** related reflector is made of lined sheets of aluminum,and the tubes are made of stainless steel used for the absorption of *** have an outer diameter of 0.051 m and a wall thickness of 0.002 ***,used as a heat transfer fluid(HTF),flows through the absorber tube at a mass flow rate of 0.7 kg/*** dimensions of cylindrical turbulators are 0.04 m in length and 0.047 m in *** are performed using the ANSYS Fluent 2020 R2 *** PTC performance is evaluated by comparing the experimental and numerical outcomes,namely,the outlet temperature,useful heat,and thermal efficiency for a modified tube(MT)(tube with novel cylindrical turbulators)and a plain tube(PT)(tube without novel cylindrical turbulators).According to the results,the experimental outlet temperatures recorded 63.2°C and 50.5°C for the MT and PT,*** heat gain reaches 1137.5 Win the MT and 685.8 Win the *** to the PT collector,the PTC exhibited a(1.64 times)higher efficiency.

关键词： Parabolic trough collector turbulators absorber tube ANSYS thermal efficiency

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Skeletal muscle as a molecular and cellular biomarker of disease progression in amyotrophic lateral sclerosis:a narrative review

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Neural Regeneration Research 2024年第4期19卷 747-753页

作者： Peter H.King Department of Neurology and Center for Neurodegeneration and Experimental Therapeutics The University of Alabama at BirminghamBirminghamALUSA Birmingham Veterans Affairs Medical Center BirminghamALUSA

Amyotrophic lateral sclerosis is a fatal multisystemic neurodegenerative disease with motor neurons being a primary *** progressive weakness is a hallmark feature of amyotrophic lateral sclerosis,there is considerable heterogeneity,including clinical presentation,progression,and the underlying triggers for disease *** on longitudinal studies with families harboring amyotrophic lateral sclerosis-associated gene mutations,it has become apparent that overt disease is preceded by a prodromal phase,possibly in years,where compensatory mechanisms delay symptom *** 85-90%of amyotrophic lateral sclerosis is sporadic,there is a strong need for identifying biomarkers that can detect this prodromal phase as motor neurons have limited capacity for *** Food and Drug Administration-approved therapies work by slowing the degenerative process and are most effective early in the *** muscle,including the neuromuscular junction,manifests abnormalities at the earliest stages of the disease,before motor neuron loss,making it a promising source for identifying biomarkers of the prodromal *** accessibility of muscle through biopsy provides a lens into the distal motor system at earlier stages and in real *** advent of“omics”technology has led to the identification of numerous dysregulated molecules in amyotrophic lateral sclerosis muscle,ranging from coding and non-coding RNAs to proteins and *** technology has opened the door for identifying biomarkers of disease activity and providing insight into disease mechanisms.A major challenge is correlating the myriad of dysregulated molecules with clinical or histological progression and understanding their relevance to presymptomatic phases of *** are two major goals of this *** first is to summarize some of the biomarkers identified in human amyotrophic lateral sclerosis muscle that have a clinicopathological correlation with disease activi

关键词： amyotrophic lateral sclerosis biomarkers clinicopathological correlation disease progression muscle biomarkers neurogenic atrophy neuromuscular junction non-coding RNAs presymptomatic stages skeletal muscle SOD1G93A mouse model

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Improving Video Watermarking through Galois Field GF(2^(4)) Multiplication Tables with Diverse Irreducible Polynomials and Adaptive Techniques

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Computers, Materials & Continua 2024年第1期78卷 1423-1442页

作者： Yasmin alaa Hassan Abdul Monem S.Rahma Department of Computer Science College of ScienceUniversity of BaghdadBaghdadIraq Department of Computer Science College of ScienceAl-Maarif University CollegeAl-AnbarIraq

Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content *** study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible *** primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution *** research employs scene selection and adaptive thresholding techniques to streamline the watermarking *** selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual ***,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and *** Peak Signal-to-Noise Ratio(PSNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video *** study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark *** parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and *** comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution *** evaluation of the proposed algorithm's robustness was conducted using PSNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack *** findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness.

关键词： Video watermarking galois field irreducible polynomial multiplication table scene selection adaptive thresholding

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Efficient ECG classification based on Chi-square distance for arrhythmia detection

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Journal of Electronic Science and Technology 2024年第2期22卷 1-15页

作者： Dhiah al-Shammary Mustafa Noaman Kadhim Ahmed M.Mahdi Ayman Ibaida Khandakar Ahmedb College of Computer Science and Information Technology University of Al-QadisiyahAl Diwaniyah58001Iraq Intelligent Technology Innovation Lab Victoria UniversityMelbourne3011Australia

This study introduces a new classifier tailored to address the limitations inherent in conventional classifiers such as K-nearest neighbor(KNN),random forest(RF),decision tree(DT),and support vector machine(SVM)for arrhythmia *** proposed classifier leverages the Chi-square distance as a primary metric,providing a specialized and original approach for precise arrhythmia *** optimize feature selection and refine the classifier’s performance,particle swarm optimization(PSO)is integrated with the Chi-square distance as a fitness *** synergistic integration enhances the classifier’s capabilities,resulting in a substantial improvement in accuracy for arrhythmia *** results demonstrate the efficacy of the proposed method,achieving a noteworthy accuracy rate of 98% with PSO,higher than 89% achieved without any previous *** classifier outperforms machine learning(ML)and deep learning(DL)techniques,underscoring its reliability and superiority in the realm of arrhythmia *** promising results render it an effective method to support both academic and medical communities,offering an advanced and precise solution for arrhythmia detection in electrocardiogram(ECG)data.

关键词： Arrhythmia classification Chi-square distance Electrocardiogram(ECG)signal Particle swarm optimization(PSO)

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Conservation laws,Lie symmetries,self adjointness,and soliton solutions for the Selkov–Schnakenberg system

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Communications in Theoretical Physics 2024年第2期76卷 29-44页

作者： Kashif ali aly R Seadawy Syed T R Rizvi Noor Aziz Department of Mathematics COMSATS University IslamabadLahore CampusPakistan Mathematics Department Faculty of ScienceTaibah UniversityAl-Madinah Al-Munawarah41411Saudi Arabia

In this article,we explore the famous Selkov–Schnakenberg(SS)system of coupled nonlinear partial differential equations(PDEs)for Lie symmetry analysis,self-adjointness,and conservation ***,miscellaneous soliton solutions like dark,bright,periodic,rational,Jacobian elliptic function,Weierstrass elliptic function,and hyperbolic solutions of the SS system will be achieved by a well-known technique called sub-ordinary differential *** these results are displayed graphically by 3D,2D,and contour plots.

关键词： Selkov-Schnakenberg system Lie symmetry analysis conservation laws adjointness integrability

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