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Finite-time tracking control of heterogeneous multi-AUV systems with partial measurements and intermittent communication

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Science China(Information Sciences) 2024年第5期67卷 165-182页

作者： Bo CHEN Jiangping HU Bijoy kumar GHOSH School of Automation Engineering University of Electronic Science and Technology of China Key Laboratory of Intelligent Analysis and Decision on Complex Systems Chongqing University of Posts and Telecommunications Yangtze Delta region Institute (Huzhou) University of Electronic Science and Technology of China Department of Mathematics and Statistics Texas Tech University

The development of a distributed trajectory-tracking control strategy that is independent of velocity measurements is critical to achieving finite-time tracking control of autonomous underwater vehicle(AUV) systems. In this study, a group of heterogeneous AUV systems with intermittent communication links is considered and a finite-time trajectory-tracking control strategy is developed. The strategy includes two observers and one controller proposed for each follower-AUV. The first observer, a hybrid finite-time observer,estimates the state of the leader, whereas the second observer, which relies only on the position measurement,is proposed to estimate the states of the follower-AUV itself. In addition, a distributed trajectory-tracking controller is designed using the states estimated by the intermittent communication network even without velocity measurements. A homogeneous technique is utilized to prove that all followers can track the leader in a finite time. Finally, the effectiveness of the developed finite-time tracking control strategy is illustrated by numerical simulations.

关键词： distributed observer finite-time tracking homogeneous technique intermittent communication multiple heterogeneous AUVs

Extension of Distribution Transformer Life in the Presence of Smart Inverter-based Distributed Solar Photovoltaic Systems

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 88-95页

作者： Kanhaiya kumar Saran Satsangi Ganesh Balu Kumbhar Department of Electrical and Electronics Engineering Motihari College of EngineeringMotihariBiharIndia Department of Electrical Engineering National Institute of Technology(NIT)PatnaPatnaBiharIndia Department of Electrical Engineering Indian Institute of Technology(IIT)RoorkeeRoorkeeUttarakhandIndia

A transformer is an essential but expensive power delivery equipment for a distribution utility.In many distribution utilities worldwide,a sizable percentage of transformers are near the end of their designed life.At the same time,distribution utilities are adopting smart inverter-based distributed solar photovoltaic(SPV)systems to maximize renewable generation.The central objective of this paper is to propose a methodology to quantify the effect of smart inverter-based distributed SPV systems on the aging of distribution transformers.The proposed method is first tested on a modified IEEE-123 node distribution feeder.After that,the procedure is applied to a practical distribution system,i.e.,the Indian Institute of Technology(IIT)roorkee campus,India.The transformer aging models,alongside advanced control functionalities of grid-tied smart inverter-based SPV systems,are implemented in MATLAB.The open-source simulation tool(OpenDSS)is used to model distribution networks.To analyze effectiveness of various inverter functionalities,time-series simulations are performed using exponential load models,considering daily load curves from multiple seasons,load types,current harmonics,etc.Findings show replacing a traditional inverter with a smart inverter-based SPV system can enable local reactive power generation and may extend the life of a distribution transformer.Simulation results demonstrate,simply by incorporating smart inverter-based SPV systems,transformer aging is reduced by 15%to 22%in comparison to SPV systems operating with traditional inverters.

关键词： Distribution transformer loss of life smart inverter functions solar photovoltaic systems thermal models Volt-VAr control

Intrusion detection systems for wireless sensor networks using computational intelligence techniques

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Cybersecurity 2024年第2期7卷 81-95页

作者： Vaishnavi Sivagaminathan Manmohan Sharma Santosh kumar Henge Lovely Professional University PhagwaraIndia

Network Intrusion Detection Systems(NIDS)are utilized to find hostile network connections.This can be accom-plished by looking at traffic network activity,but it takes a lot of work.The NIDS heavily utilizes approaches for data extraction and machine learning to find anomalies.In terms of feature selection,NIDS is far more effective.This is accurate since anomaly identification uses a number of time-consuming features.Because of this,the feature selec-tion method influences how long it takes to analyze movement patterns and how clear it is.The goal of the study is to provide NIDS with an attribute selection approach.PSO has been used for that purpose.The Network Intrusion Detection System that is being developed will be able to identify any malicious activity in the network or any unusual behavior in the network,allowing the identification of the illegal activities and safeguarding the enormous amounts of confidential data belonging to the customers from being compromised.In the research,datasets were produced utilising both a network infrastructure and a simulation network.Wireshark is used to gather data packets whereas Cisco Packet Tracer is used to build a network in a simulated environment.Additionally,a physical network consisting of six node MCUs connected to a laptop and a mobile hotspot,has been built and communication packets are being recorded using the Wireshark tool.To train several machine learning models,all the datasets that were gatheredcre-ated datasets from our own studies as well as some common datasets like NSDL and UNSW acquired from Kaggle-were employed.Additionally,PsO,which is an optimization method,has been used with these ML algorithms for feature selection.In the research,KNN,decision trees,and ANN have all been combined with PSO for a specific case study.And it was found demonstrated the classification methods PSO+ANN outperformed PSO+KNN and PSO+DT in this case study.

关键词： Network intrusion detection systems(NIDS) Cisco packet tracer Wireshark tool Machine learning PSO Cybersecurity Optimization

Current status of the biliary tract malformation

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World Journal of Clinical Pediatrics 2024年第2期13卷 100-103页

作者： Krishna kumar Govindarajan Department of Pediatric Surgery JIPMERPondicherryPondicherry 605006India

The choledochal cyst(CC)can be better termed as biliary tract malformation because of the close association of embryology and etiology in the causation of CC.Contrary to Babbitt's postulation of reflux,damage and dilatation,reflux was not demonstrable as the causative factor in all varieties of CC.High pressure in the biliary system,otherwise termed ductal hypertension,is put forth as an alternative to explain the evolution of CC.The forme fruste type,which does not find a place in the standard classification,typifies the ductal hypertension hypothesis.Hence a closer,in-depth review would be able to highlight this apt terminology of biliary tract malformation.

关键词： Choledochal cyst Biliary tract Biliary dilatation Ductal hypertension Common channel Pancreatobiliary malunion

Implications of regional identity for neural stem and progenitor cell transplantation in the injured or diseased nervous system

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Neural regeneration research 2024年第4期19卷 715-716页

作者： Prakruthi Amar.kumar Jennifer N.Dulin Department of Biology Texas A&M UniversityCollege Station Texas A&M Institute for Neuroscience Texas A&M UniversityCollege Station

Neural stem and progenitor cell(NSPC)transpla ntation has emerged as a promising therapeutic strategy for replacing lost neuronal populations and repairing damaged neural circuits following nervous system injury and disease.A great deal of experimental work has investigated the biology of NSPC grafting in preclinical animal models;more recently.

关键词： neural system injured

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Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay kumar Shah Hao Wang Said El-Hawwat Centre of Advanced Infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance strategies.This study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE pipe.Laboratory experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch configuration.Mode dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack growth.The findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

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Gravity-driven powder flow and the influence of external vibration on flow characteristics

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Particuology 2024年第5期88卷 201-209页

作者： Muhammad Shahid Ansari ratna kumar Annabattula Sathyan Subbiah Department of Mechanical Engineering Indian Institute of Technology MadrasChennai 600036India

The controlled and homogeneous flow of dry granular powders through hoppers is essential for applications,namely,packaging of food grains,fertilizers and additive manufacturing processes such as directed energy deposition for better product quality.One of the major issues encountered in the granular flows through hoppers is flow stagnation due to the well-known arching phenomenon.Vibration-assisted granular flow through hoppers is one of the mechanisms used for better mass flow control.In this work,the influence of external mechanical vibration on the powder flow is investigated experimentally and using discrete element simulations.First,the mass flow rate through the hopper increases with an increase in vibration amplitude and then decreases,signifying the existence of an optimal amplitude of vibration.The DEM simulations explained the underlying mechanisms for the existence of an optimal amplitude of vibration corresponding to the maximum mass flow rate.A range of vibration amplitudes from 0 mm to 3.5 mm is used to study the flow behaviour;the maximum flow of around 33 g/s to 35 g/s is observed for 0.75 mm to 1.25 mm vibration amplitude for the hopper-particle combination studied in this work.The work also reports the influence of vibration frequency,hopper,and particle dimension on the flow characteristics.The research facilitates the effective use of mechanical vibration to enhance powder flow that can further be extended to non-spherical and multi-material particles.

关键词： Discrete element method Flow rate Granular flow Path tracking Vibration intensity

Nutrition interventions and clinical outcomes of pregnant women with gestational diabetes mellitus: More than meets the eye

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World Journal of Diabetes 2024年第1期15卷 126-128页

作者： Sony Sinha Prateek Nishant ranjeet kumar Sinha Arvind kumar Morya ripunjay Prasad Department of Ophthalmology-Vitreo-retina Neuro-Ophthalmology and OculoplastyAll India Institute of Medical SciencesPatnaPatna 801507BiharIndia Department of Ophthalmology ESIC Medical CollegePatnaPatna 801103BiharIndia Department of Community Medicine Patna Medical CollegePatna 800004BiharIndia Department of Ophthalmology All India Institute of Medical SciencesHyderabad 508126TelanganaIndia Department of Ophthalmology RP Eye InstituteDelhi 110001DelhiIndia

In the retrospective study by Luo et al regarding clinical outcomes in gestational diabetes mellitus(GDM),the results are statistically significant in favour of the benefits of individualized nutrition interventions enumerated therein.The study has provided important evidence to improve maternal and child health in the Asian population.The methods,however,appear to have considerable limi-tations,wherein the time point of diagnosis of GDM,severity of GDM,selection bias,compliance to therapy,important maternal covariates,observable microvascular abnormalities and the confounding effect of added insulin have not been considered.We have provided suggestions to improve the external validity of the study,including the use of Equator Network reporting guidelines and inclusion of overweight and obese patients in future studies.

关键词： Glucose intolerance Hyperglycemia Obesity Pregnancy research methodology

Secure and resilient improved image steganography using hybrid fuzzy neural network with fuzzy logic

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Journal of Safety Science and resilience 2024年第1期5卷 91-101页

作者： Sachin Dhawan Hemanta kumar Bhuyan Subhendu kumar Pani Vinayakumar ravi rashmi Gupta Arun rana Alanoud Al Mazroa Dorset College King George BlvdSurreyBritish ColumbiaCanada Department of Information Technology Vignan’s Foundation for ScienceTechnology and Research(Deemed to be University)Andhra PradeshIndia Krupajal Computer Academy Biju Patnaik University of Technology(BPUT)Rourkela 751002India Center for Artificial Intelligence Prince Mohammad Bin Fahd UniversityKhobarSaudi Arabia NSUT East Campus(Formerly AIACTRDelhi 110031India(Affiliated to Guru Gobind Singh Inderaprastha University))Dwarka 110078India Department of Computer Science and Engineering Galgotias College of Engineering and Technology Greater Noida 201310Uttar PradeshIndia Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman University(PNU)P.O.Box 84428Riyadh 11671Saudi Arabia

The exponential growth in communication networks,data technology,advanced libraries,and mainly World Wide Web services has played a pivotal role in facilitating the retrieval of various types of information as needed.However,this progress has also led to security concerns related to the transmission of confidential data.Nevertheless,safeguarding these data during communication through insecure channels is crucial for obvious reasons.The emergence of steganography offers a robust approach to concealing confidential information,such as images,audio tracks,text files,and video files,in suitable media carriers.A novel technique is envisioned based on back-propagation learning.According to the proposed method,a hybrid fuzzy neural network(HFNN)is applied to the output obtained from the least significant bit substitution of secret data using pixel value dif-ferences and exploiting the modification direction.Through simulation and test results,it has been observed that the proposed methodology achieves secure steganography and superior visual quality.During the experiments,we observed that for the secret image of the cameraman,the PSNr&MSE values of the proposed technique are 61.963895 and 0.041361,respectively.

关键词： Image enhancement Image processing Steganography Deep learning Fuzzy neural combination