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Robust design of sliding mode control for airship trajectory tracking with uncertainty and disturbance estimation

Journal of Systems Engineering and Electronics 2024年第1期35卷 242-258页

作者： WASIM Muhammad ALI Ahsan CHOUDHRY Mohammad Ahmad shaikh inam ul Hasan SALEEM Faisal Department of Aeronautics and Astronautics Engineering Institute of Space TechnologyIslamabad 44000Pakistan Department of Electrical Engineering University of Engineering and TechnologyTaxila 47080Pakistan Department of Measurements and Control Systems Silesian University of TechnologyGliwice 44-101Poland The Joint Doctoral School Silesian University of TechnologyGliwice 44-100Poland

The robotic airship can provide a promising aerostatic platform for many potential applications.These applications require a precise autonomous trajectory tracking control for airship.Airship has a nonlinear and uncertain dynamics.It is prone to wind disturbances that offer a challenge for a trajectory tracking control design.This paper addresses the airship trajectory tracking problem having time varying reference path.A lumped parameter estimation approach under model uncertainties and wind disturbances is opted against distributed parameters.It uses extended Kalman filter(EKF)for uncertainty and disturbance estimation.The estimated parameters are used by sliding mode controller(SMC)for ultimate control of airship trajectory tracking.This comprehensive algorithm,EKF based SMC(ESMC),is used as a robust solution to track airship trajectory.The proposed estimator provides the estimates of wind disturbances as well as model uncertainty due to the mass matrix variations and aerodynamic model inaccuracies.The stability and convergence of the proposed method are investigated using the Lyapunov stability analysis.The simulation results show that the proposed method efficiently tracks the desired trajectory.The method solves the stability,convergence,and chattering problem of SMC under model uncertainties and wind disturbances.

关键词： airship chattering extended Kalman filter(EKF) model uncertainties estimation sliding mode controller(SMC)

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Application and comparison of kernel functions for linear parameter varying model approximation of nonlinear systems

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Applied Mathematics(A Journal of Chinese Universities) 2023年第1期38卷 58-77页

作者： Faisal Saleem Ahsan Ali inam-ul-hassan shaikh Muhammad Wasim Department of Measurements and Control Systems Silesian University of TechnologyGliwicePoland Department of Electrical Engineering University of Engineering and TechnologyTaxilaPakistan Department of Aeronautics and Astronautics Engineering Institute of Space TechnologyIslamabadPakistan

In this paper,a comparative study for kernel-PCA based linear parameter varying(LPV)model approximation of sufficiently nonlinear and reasonably practical systems is carried out.Linear matrix inequalities(LMIs)to be solved in LPV controller design process increase exponentially with the increase in a number of scheduling variables.Fifteen kernel functions are used to obtain the approximate LPV model of highly coupled nonlinear systems.An error to norm ratio of original and approximate LPV models is introduced as a measure of accuracy of the approximate LPV model.Simulation examples conclude the effectiveness of kernel-PCA for LPV model approximation as with the identification of accurate approximate LPV model,computation complexity involved in LPV controller design is decreased exponentially.

关键词： kernel-PCA LMIs LPV error to norm ratio computational complexity and control design

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Triad-displaced ulAs configuration for non-circular sources with larger continuous virtual aperture and enhanced degrees of freedom

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Journal of Systems Engineering and Electronics 2024年第1期35卷 81-93页

作者： shaikh Abdul Hayee DANG Xiaoyu HUANG Daqing College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Non-uniform linear array(NulA)configurations are well renowned due to their structural ability for providing increased degrees of freedom(DOF)and wider array aperture than uniform linear arrays(ulAs).These characteristics play a significant role in improving the direction-of-arrival(DOA)estimation accuracy.However,most of the existing NulA geometries are primarily applicable to circular sources(CSs),while they limitedly improve the DOF and continuous virtual aperture for noncircular sources(NCSs).Toward this purpose,we present a triaddisplaced ulAs(Tdis-ulAs)configuration for NCS.The TdisulAs structure generally consists of three ulAs,which are appropriately placed.The proposed antenna array approach fully exploits the non-circular characteristics of the sources.Given the same number of elements,the Tdis-ulAs design achieves more DOF and larger hole-free co-array aperture than its sparse array competitors.Advantageously,the number of uniform DOF,optimal distribution of elements among the ulAs,and precise element positions are uniquely determined by the closed-form expressions.Moreover,the proposed array also produces a filled resulting co-array.Numerical simulations are conducted to show the performance advantages of the proposed Tdis-ulAs configuration over its counterpart designs.

关键词： direction-of-arrival(DOA)estimation sparse array non-circular source(NCS) sum co-array difference co-array degrees of freedom(DOF)

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Metabolic puzzle: Exploring liver fibrosis differences in Asian metabolic-associated fatty liver disease subtypes

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World Journal of Hepatology 2024年第1期16卷 54-64页

作者： Sabhita Shabir shaikh Fakhar Ali Qazi-Arisar Saba Nafay Sidra Zaheer Hafeezullah shaikh Zahid Azam National Institute of Liver and GI Diseases Dow University of Health SciencesSindhKarachi 75330Pakistan School of Public Health Dow University of Health SciencesSindhKarachi 75330Pakistan

BACKGROUND Metabolic-associated fatty liver disease(MAFLD)is a liver condition marked by excessive fat buildup in the absence of heavy alcohol use.It is primarily linked with metabolic issues like insulin resistance,obesity,and abnormal lipid levels,and is often observed with other conditions such as type 2 diabetes and cardiovascular disease.However,whether the subtypes of MAFLD based on the metabolic disorder differentially impact liver fibrosis is not well explicated,especially in the Asian population.AIM To compare the severity of liver fibrosis among different MAFLD subtypes.METHODS A total of 322 adult patients of either gender with fatty liver on ultrasound were enrolled between January to December 2021.MAFLD was defined as per the Asian Pacific Association for the Study of the Liver guidelines.Fibrosis-4 index(Fib-4)and nonalcoholic fatty liver disease fibrosis score(NFS)were employed to evaluate liver fibrosis.RESulTS The mean age was 44.84±11 years.Seventy-two percent of the patients were female.Two hundred and seventy-three patients were classified as having MAFLD,of which 110(40.3%)carried a single,129(47.3%)had two,and 34(12.5%)had all three metabolic conditions.The cumulative number of metabolic conditions was related to elevated body mass index,triglyceride(TG)levels,and glycated hemoglobin,lower high-density lipoprotein(HDL)levels,higher liver inflammation(by aspartate aminotransferase andγ-glutamyl transferase),and higher likelihood of fibrosis(by NFS and Fib-4 scores)(P<0.05 for all).The proportion of advanced fibrosis also increased with an increase in the number of metabolic conditions(4.1%,25.5%,35.6%,and 44.1%by NFS and 6.1%,10.9%,17%,and 26.5%by Fib-4 for no MAFLD and MAFLD with 1,2,and 3 conditions,respectively).Among MAFLD patients,those with diabetes alone were the eldest and had the highest mean value of NFS score and Fib-4 score(P<0.05),while MAFLD patients diagnosed with lean metabolic dysfunction exhibited the highest levels of TG and alanine aminotransferase but the lowest HDL level

关键词： Metabolic syndrome Diabetes Fatty liver disease Dyslipidemia Obesity

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Geomorphic signatures and active tectonics in western Saurashtra,Gujarat,India

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Geodesy and Geodynamics 2024年第1期15卷 82-99页

作者： Bikramaditya Mondal Mery Biswas Soumyajit Mukherjee Mohamedharoon A.shaikh Department of Earth Sciences Indian Institute of Technology BombayMumbai 400076MaharashtraIndia Department of Geography Presidency UniversityKolkata 700073West BengalIndia

Active tectonics in an area includes ongoing or recent geologic events.This paper investigates the tectonic influence on the subsidence,uplift and tilt of western Saurashtra through morphotectonic analysis of ten watersheds along with characteristics of relief and drainage orientation.Watersheds 7-9 to the north(N)are tectonically active,which can be linked with the North Kathiawar Fault System(NKFS)and followed by watersheds 6,10,1,4 and 5.Stream-length gradient index and sinuosity index indicate the effect of tectonic events along the master streams in watersheds 6-9.Higher R^(2)values of the linear curve fit for watershed 7 indicate its master stream is much more tectonically active than the others.The R^(2)curve fitting model and earthquake magnitude/depth analysis confirm the region to be active.The reactivation of the NKFS most likely led to the vertical movement of western Saurashtra.

关键词： Active tectonics Geomorphology Western Saurashtra Archeology North kathiawar fault system

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Fine Sand and Clay Sediment Acoustic Properties of the Novel Sediment Sample from the Arabian Sea:Experimental Investigations and Biot−Stoll Model Validation

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China Ocean Engineering 2024年第1期38卷 169-180页

作者： Shahabuddin shaikh HUANG Yi-wang ZHANG Ze-chuan Habib Hussain ZUBERI National Key Laboratory of Underwater Acoustic Technology and College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China

The present study explores the physical and acoustic characteristics of fine sand and clay in novel seabed marine sediments from of Pakistan coastline of the Arabian Sea.The measured physical parameters included mean grain size,mass density,bulk density,salinity,porosity,permeability,pore size and mineralogical composition.Acoustic properties,including sound speed and attenuation,in the high frequency range of 90-170 kHz were analyzed.A controlled laboratory setup with the acoustic transmission method and Fourier transform techniques was utilized to examine the sound propagation and absorption of novel seabed sediments.The standard deviation of mean sound speed in fresh water was 0.75 m/s,and attenuation was observed in the range of 0.43 to 0.61 dB/m.The mean sound velocity in sand and clay varied from 1706 to 1709 m/s and 1602 to 1608 m/s,respectively.Corresponding average attenuation was observed at 80 to 93 dB/m in sandy sediments and from 31.8 to 38.6 dB/m in clayey sediments.Sound velocity variation within sandy sediment is low,consistent with expected results,and smaller than the predicted uncertainty.However,clay sediment exhibited a positive linear correlation and low sound speed variation.Attenuation increased linearly with frequency for both sediments.Finally,the laboratory results were validated by using the Biot−Stoll model.The dispersion of sound speed in sandy and clayey sediments was consistent with the predictions of the Biot−Stoll model.Measured attenuation aligned more with Biot−Stoll model predictions due to improved permeability,tortuosity and pore size parameter fitting.

关键词： physical and acoustic characteristics marine sediments sound speed attenuation Biot−Stoll model

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Understanding the catalytic performance and deactivation behaviour of second-promoter doped Pt/WO_(χ)/γ-Al_(2)O_(3) catalysts in the glycerol hydrogenolysis for selective and cleaner production of 1,3-propanediol

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Journal of Energy Chemistry 2024年第7期94卷 486-507页

作者： Rafik Rajjak shaikh Sittichai Damruang Rais Ahmad Khan Supareak Praserthdam Piyasan Praserthdam Center of Excellence on Catalysis and Catalytic Reaction Engineering(CECC) Department of Chemical EngineeringFaculty of EngineeringChulalongkorn UniversityBangkok 10330Thailand Department of Chemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia High-Performance Computing Unit(CECC-HCU) Centre of Excellence on Catalysis and Catalytic Reaction Engineering(CECC)Department of Chemical EngineeringFaculty of EngineeringChulalongkorn UniversityBangkok 10330Thailand

The selective aqueous-phase glycerol hydrogenolysis is a promising reaction to produce commercially useful 1,3-propanediol(1,3-PDO).The Pt-WOx bifunctional catalyst can catalyse the glycerol hydrogenol-ysis but the catalyst deactivation via sintering,metal leaching,and coking can predominantly occur in the aqueous phase reaction.In this work,the effect of reaction temperature,pressure and second promoter(Cu,Fe,Rh,Mn,Re,Ru,Ir,Sn,B,and P)on catalytic performance and deactivation behaviour of Pt/WOx/-Al2O3 was investigated.When doped with Rh,Mn,Re,Ru,Ir,B,and P,the second promoter boosts cat-alytic activity by promoting great dispersion of Pt on support and increasing Pt surface area.The increased Bronsted acid sites lead to selective synthesis of 1,3-PDO than 1,2-propanediol(1,2-PDO).The characterization studies of fresh and spent catalysts reveal that the main cause of catalyst deactiva-tion is the Pt sintering,as interpreted based on XRD,CO chemisorption,and TEM analyses.The Pt sinter-ing is affected depending on the second promoter that can either or reduce the interaction between Pt,WO_(χ)/γ and Al_(2)O_(3).As an electron acceptor of Pt in Pt/WO_(χ)/γ-Al_(2)O_(3),Re and Mn as second promoters resulted in increased Pt^(2+) on the catalytic surface,which strengthens the contact between Pt andγ-Al_(2)O_(3) and WO_(χ),resulting in a decrease in Pt sintering.The metal leaching and coking are not affected by the presence of second promoter.The catalyst modified with a second promoter possesses improved catalytic activity and 1,3-PDO production,however the stability continues to remain a challenge.The present work unrav-elled the determining parameters of catalytic activity and deactivation,thus providing a promising pro-tocol toward effective catalysts for glycerol hydrogenolysis.

关键词： Glycerol hydrogenolysis 1,3-propanediol Metal-support interaction Second promoter Liquid phase Catalyst deactivation

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Social Media-Based Surveillance Systems for Health Informatics Using Machine and Deep Learning Techniques:A Comprehensive Review and Open Challenges

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1167-1202页

作者： Samina Amin Muhammad Ali Zeb Hani Alshahrani Mohammed Hamdi Mohammad Alsulami Asadullah shaikh Institute of Computing Kohat University of Science and TechnologyKohat26000Pakistan Department of Computer Science College of Computer Science and Information SystemsNajran UniversityNajran61441Saudi Arabia Department of Information System College of Computer Science and Information SystemsNajran UniversityNajran61441Saudi Arabia

Social media(SM)based surveillance systems,combined with machine learning(ML)and deep learning(DL)techniques,have shown potential for early detection of epidemic outbreaks.This review discusses the current state of SM-based surveillance methods for early epidemic outbreaks and the role of ML and DL in enhancing their performance.Since,every year,a large amount of data related to epidemic outbreaks,particularly Twitter data is generated by SM.This paper outlines the theme of SM analysis for tracking health-related issues and detecting epidemic outbreaks in SM,along with the ML and DL techniques that have been configured for the detection of epidemic outbreaks.DL has emerged as a promising ML technique that adaptsmultiple layers of representations or features of the data and yields state-of-the-art extrapolation results.In recent years,along with the success of ML and DL in many other application domains,both ML and DL are also popularly used in SM analysis.This paper aims to provide an overview of epidemic outbreaks in SM and then outlines a comprehensive analysis of ML and DL approaches and their existing applications in SM analysis.Finally,this review serves the purpose of offering suggestions,ideas,and proposals,along with highlighting the ongoing challenges in the field of early outbreak detection that still need to be addressed.

关键词： Social media epidemic machine learning deep learning health informatics pandemic

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Microphallus early management in infancy saves adulthood sensual life:A comprehensive review

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World Journal of Clinical Pediatrics 2024年第2期13卷 16-37页

作者： Mohammed Al-Beltagi Nermin Kamal Saeed Adel Salah Bediwy Majed A shaikh Reem Elbeltagi Department of Pediatric Faculty of MedicineTanta UniversityTanta 31511Egypt Department of Pediatric University Medical CenterKing Abdulla Medical CityArabian Gulf UniversityManama 26671Bahrain Department of Pediatric University Medical CenterSulaiman Al Habib Medical GroupManama 26671Bahrain Department of Medical Microbiology Section and Pathology Salmaniya Medical ComplexMinistry of HealthKingdom of BahrainManama 12Bahrain Department of Medical Microbiology Section and Pathology Irish Royal College of SurgeonBusaiteen 15503Bahrain Department of Pulmonology Faculty of MedicineTanta UniversityTanta 31527Egypt Department of Pulmonology University Medical CenterKing Abdulla Medical CityArabian Gulf UniversityManama 26671Bahrain Department of Pulmonology University Medical CenterSulaiman Al Habib Medical GroupManama 26671Bahrain Department of Pediatrics Ibn Al Nafees HospitalManama 54533Bahrain Department of Medicine The Royal College of Surgeons in Ireland-BahrainBusiateen 15503Bahrain

Microphallus/Micropenis is a rare condition with significant physical and psychological implications for affected individuals.This article comprehensively reviews micropenis,its etiology,epidemiology,and various treatment options.We conducted a thorough literature review to collect relevant information on micropenis and microphallus,as well as related disorders.Our primary databases were PubMed,Medline,and Google Scholar.We searched for articles published in English between 2000 and 2023.Our analysis included 67 review articles,56 research studies,11 case reports,one guideline,and one editorial.Our search terms included"microphallus","micropenis","congenital hypogonadotropic hypogonadism","androgen insensitivity syndrome","pediatric management of micropenis","testosterone therapy",and"psychosocial implications of micropenis".We focused on diagnosing micropenis and related conditions,including hormonal assessments,medical and surgical treatment options,psychosocial and psychological well-being,sexual development of adolescents,and sociocultural influences on men's perceptions of penile size.Additionally,we explored parenting and family dynamics in cases of micropenis and disorders of sex development,implications of hormonal treatment in neonates,and studies related to penile augmentation procedures and their effectiveness.The article highlights the importance of early diagnosis and intervention in addressing the physical and psychological well-being of individuals with micropenis.Surgical procedures,such as penile lengthening and girth enhancement,and non-surgical approaches like hormonal therapy are explored.The significance of psychological support,education,and lifestyle modifications is emphasized.Early management and comprehensive care are crucial for individuals with micropenis,from infancy to adolescence and beyond.A multidisciplinary approach involving urologists,endocrinologists,and mental health professionals is recommended.Regular assessment of treatment effectiveness and the need for updated guidelines

关键词： Microphallus Micropenis Hypogonadism Children Adults Sensual life Testosterone therapy

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Gradient Optimizer Algorithm with Hybrid Deep Learning Based Failure Detection and Classification in the Industrial Environment

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1341-1364页

作者： Mohamed Zarouan Ibrahim M.Mehedi shaikh Abdul Latif Md.Masud Rana Department of Electrical and Computer Engineering(ECE) King Abdulaziz UniversityJeddah21589Saudi Arabia Center of Excellence in Intelligent Engineering Systems(CEIES) King Abdulaziz UniversityJeddah21589Saudi Arabia Department of Nuclear Engineering King Abdulaziz UniversityJeddah21589Saudi Arabia Department of Electrical and Electronic Engineering Rajshahi University of Engineering and TechnologyRajshahiBangladesh

Failure detection is an essential task in industrial systems for preventing costly downtime and ensuring the seamlessoperation of the system. Current industrial processes are getting smarter with the emergence of Industry 4.0.Specifically, various modernized industrial processes have been equipped with quite a few sensors to collectprocess-based data to find faults arising or prevailing in processes along with monitoring the status of processes.Fault diagnosis of rotating machines serves a main role in the engineering field and industrial production. Dueto the disadvantages of existing fault, diagnosis approaches, which greatly depend on professional experienceand human knowledge, intellectual fault diagnosis based on deep learning (DL) has attracted the researcher’sinterest. DL reaches the desired fault classification and automatic feature learning. Therefore, this article designs a Gradient Optimizer Algorithm with Hybrid Deep Learning-based Failure Detection and Classification (GOAHDLFDC)in the industrial environment. The presented GOAHDL-FDC technique initially applies continuous wavelettransform (CWT) for preprocessing the actual vibrational signals of the rotating machinery. Next, the residualnetwork (ResNet18) model was exploited for the extraction of features from the vibration signals which are thenfed into theHDLmodel for automated fault detection. Finally, theGOA-based hyperparameter tuning is performedtoadjust the parameter valuesof theHDLmodel accurately.The experimental result analysis of the GOAHDL-FD Calgorithm takes place using a series of simulations and the experimentation outcomes highlight the better resultsof the GOAHDL-FDC technique under different aspects.

关键词： Fault detection Industry 4.0 gradient optimizer algorithm deep learning rotating machineries artificial intelligence

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