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Dynamic event-triggered fault-tolerant cooperative resilient tracking control with prescribed performance for UAVs

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Science China(Information Sciences) 2024年第8期67卷 67-84页

作者： Rong YUAN Zhengcai AN Shuyi SHAO Mou CHEN Mihai LUNGU College of Automation Engineering Nanjing University of Aeronautics and Astronautics Science and Technology on Electro-optic Control Laboratory Faculty of Electrical Engineering University of Craiova Aerospace Engineering doctoral School University Politehnica of Bucharest

In this paper, a resilient tracking control scheme with cooperative collision avoidance performance is studied for the fixed-wing unmanned aerial vehicle(UAV) leader-follower formation in the presence of actuator failures and external disturbances. Firstly, based on the control objectives of UAV formation tracking and collision avoidance, the transformation tracking errors are obtained using the prescribed performance control technique. Next, a fault detection mechanism is introduced to determine if there is the actuator fault. Subsequently, the event-triggered resilient fault observers are designed based on a dynamic eventtriggered mechanism to estimate actuator faults. Furthermore, the prescribed performance functions and the H∞ performance index are employed to ensure the UAV formation collision-free and mitigate the impact of disturbances. Moreover, the resilient controller is designed to minimize the effect of the perturbations for the control gain and the fault observer gain on the system. The stability of the system is also proven through the Lyapunov stability analysis, and the controller gains are calculated by solving the linear matrix ***, the validity of the proposed control strategy is demonstrated by the simulation analysis.

关键词： UAV formation cooperative collision avoidance event-triggered fault observer prescribed performance resilient control

Exactly Solvable Two-Parameter Models of Relativistic δ′s -Sphere Interactions in Quantum Mechanics

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1263-1285页

作者： Jules Manirambona Juma Shabani Alfred Vyabandi doctoral School University of Burundi Bujumbura Burundi Faculty of Sciences Doctoral School University of Burundi Bujumbura Burundi Institute of Applied Pedagogy University of Burundi Bujumbura Burundi

We make a systematic study of two-parameter models of δ ′ s -sphere interaction and δ ′ s -sphere plus a Coulomb interaction. Where δ ′ s interaction denotes the δ ′ -sphere interaction of the second kind. We provide the mathematical definitions of Hamiltonians and obtain new results for both models, in particular the resolvents equations, spectral properties and some scattering quantities.

关键词： Boundary Conditions Problem -Sphere Interactions Self-Adjoint Operator Resolvent Equation Spectral Properties Scattering Theory

The importance of post-COVID condition phenotypes characterization to decipher the mechanisms underlying this post-viral syndrome

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World Journal of Pediatrics 2024年第6期20卷 633-634页

作者： Jon Izquierdo-Pujol Sara Moron-Lopez IrsiCaixa and Institute for Health Science Research Germans Trias i Pujol(IGTP) Can Ruti CampusBadalonaSpain Biomedicine doctoral programme Faculty of BiologyUniversity of BarcelonaBarcelonaSpain CIBERINFEC MadridSpain

The coronavirus disease-19(COVID-19)outbreak,caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),was declared a global pandemic in March *** has affected over 700 million people worldwide and resulted in almost 7 million deaths,equating to a 1%mortality *** present,the majority of COVID-19 cases are either asymptomatic or mild,typically resolving within two ***,between 1%and 10%of COVID-19 survivors do not fully recover and experience a post-viral syndrome referred to as"long COVID","post-acute COVID-19 syndrome"(PASC),or"post-COVID condition"(PCC).This post-viral syndrome affects both adult and pediatric ***,most of the studies published to date evaluate the adult population,leaving a gap in our understanding of its impact on children and adolescents.

关键词： acute mortality respiratory

Non-pancreatic hyperlipasemia:A puzzling clinical entity

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World Journal of Gastroenterology 2024年第19期30卷 2538-2552页

作者： Krisztina Eszter Feher David Tornai Zsuzsanna Vitalis Laszlo Davida Nora Sipeki Maria Papp Division of Gastroenterology Department of Internal MedicineFaculty of MedicineUniversity of DebrecenDebrecen H-4032Hajdu-BiharHungary Kalman Laki doctoral School of Biomedical and Clinical Sciences Faculty of MedicineUniversity of DebrecenDebrecen H-4032Hungary

BACKGROUND Increased lipase level is a serological hallmark of the diagnosis of acute pancreatitis(AP)but can be detected in various other diseases associated with lipase leakage due to inflammation of organs surrounding the pancreas or reduced renal clearance and/or hepatic *** non-pancreatic hyperlipasemia(NPHL)is puzzling for attending physicians during the diagnostic procedure for *** would be clinically beneficial to identify the clinical and laboratory variables that hinder the accuracy of lipase diagnosis with the aim of improve it.A more precise description of the NPHL condition could potentially provide prognostic factors for adverse outcomes which is currently *** To perform a detailed clinical and laboratory characterization of NPHL in a large prospective patient cohort with an assessment of parameters determining disease *** A Hungarian patient cohort with serum lipase levels at least three times higher than the upper limit of normal(ULN)was prospectively evaluated over 31 *** were identified using daily electronic laboratory reports developed to support an ongoing observational,multicenter,prospective cohort study called the EASY trial(ISRCTN10525246)to establish a simple,easy,and accurate clinical scoring system for early prognostication of *** of NPHL was established based on≥3×ULN serum lipase level in the absence of abdominal pain or abdominal imaging results characteristic of *** A total of 808 patients[male,n=420(52%);median age(IQR):65(51-75)years]were diagnosed with≥3×ULN serum lipase levels.A total of 392 patients had AP,whereas 401 had NPHL with more than 20 different *** and acute kidney injury(AKI)were the most prevalent etiologies of NPHL(27.7%and 33.2%,respectively).The best discriminative cut-off value for lipase was≥666 U/L(sensitivity,71.4%;specificity,88.8%).The presence of AKI or sepsis negatively affected the diagnostic performance of *** w

关键词： Non-pancreatic hyperlipasemia Acute pancreatitis Glycoprotein 2 Acute kidney injury Sepsis Mortality

Niche differentiation among facultative filter feeders: Insights from invasive Ponto-Caspian mysids

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Current Zoology 2024年第4期70卷 513-521页

作者： Péter Borza Varsha Rani Csaba F.Vada Institute of Aquatic Ecology Centre for Ecological ResearchKarolina ut 29.1113 BudapestHungary doctoral School of Biology Institute of BiologyEotvos Lorand UniversityPazmany Péter sétany 1/C1117 BudapestHungary

The degree of dietary specialization has a fundamental impact on the ecological function and interactions of suspension *** niche differentiation by food particle size is common among obligate suspension feeders,its role is not evident in facultative *** this study,we aimed at providing new insights on the matter by focusing on sympatric mysid *** mysids use different mechanisms for raptorial and filter-feeding,they represent a more adequate model system than for example,the more extensively studied *** made morpholog-ical measurements on the 4 coexisting invasive Ponto-Caspian mysid species to determine the areas and mesh sizes of their *** also quantified their clearance rates on the microalga Cryptomonas *** a laboratory experiment to reveal how morphological differences manifest in their overall filtering *** found relatively small but consistent differences in the primary filter area among the species,indicating that morphological constraints due to the enclosed position of the setae might limit the possibility for *** primary filter mesh sizes were small in all 4 species(0.69-2.73μm)with moderate but consistent intraspecific differences,suggesting that the benefit of being able to capture small particles might outweigh the pressure for *** observed clearance rates were in accordance with the morphological characteristics of the species,highlighting that auxiliary filters(present in one of the species,Limnomysis benedeni)are needed to increase filtering capacity *** study confirmed that food particle size can contribute to the niche differentiation of facultative filter feeders,but also indicated that they can tolerate a higher overlap than obligate *** observed differences were related to the habitat preferences and predatory potentials of the species,suggesting that complementarity among the different niche axes might further facilitate theircoexistence.

关键词： clearance rate coexistence filter area filtermesh size.

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

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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 require a precise autonomous trajectory tracking control for *** has a nonlinear and uncertain *** is prone to wind disturbances that offer a challenge for a trajectory tracking control *** 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 *** uses extended Kalman filter(EKF)for uncertainty and disturbance *** estimated parameters are used by sliding mode controller(SMC)for ultimate control of airship trajectory *** comprehensive algorithm,EKF based SMC(ESMC),is used as a robust solution to track airship *** proposed estimator provides the estimates of wind disturbances as well as model uncertainty due to the mass matrix variations and aerodynamic model *** stability and convergence of the proposed method are investigated using the Lyapunov stability *** simulation results show that the proposed method efficiently tracks the desired *** 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)

Influence of Various Earth-Retaining Walls on the Dynamic Response Comparison Based on 3D Modeling

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2835-2863页

作者： Muhammad Akbar Huali Pan Jiangcheng Huang Bilal Ahmed Guoqiang Ou Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu610000China Institute of International Rivers and Eco-Security Yunnan UniversityKunming650500China Department of Structural Engineering Faculty of Civil EngineeringDoctoral SchoolAkademicka 2Silesian University of TechnologyGliwice44-100Poland

The present work aims to assess earthquake-induced earth-retaining(ER)wall *** study is on the dynamics analysis of various earth-retaining wall designs in hollow precast concrete panels,reinforcement concrete facing panels,and gravity-type earth-retaining *** finite element(FE)simulations utilized a 3D plane strain condition to model full-scale ER walls and numerous nonlinear dynamics *** seismic performance of differentmodels,which includes reinforcement concrete panels and gravity-type and hollowprecast concrete ER walls,was simulated and examined using the FE *** also displays comparative studies such as stress distribution,deflection of the wall,acceleration across the wall height,lateral wall displacement,lateral wall pressure,and backfill plastic *** components of the created ER walls were found throughout this research *** is a granular reinforcement backfill,while the other is a wall-facing panel and base *** dynamic response effects of varied earth-retaining walls have also been *** was discovered that the facing panel of the model significantly impacts the earthquake-induced displacement of ER *** proposed analytical model’s validity has been evaluated and compared with the reinforcement concrete facing panels,gravity-type ER wall,scientifically available data,and American Association of State Highway and Transportation Officials(AASHTO)guidelines results based on FE *** results of the observations indicate that the hollow prefabricated concrete ER wall is the most feasible option due to its lower displacement and high-stress distribution compared to the two *** methodology and results of this study establish standards for future analogous investigations and professionals,particularly in light of the increasing computational capabilities of desktop computers.

关键词： Seismic analysis finite element modeling earth-retaining ER walls dynamic response structural resilience

Morphometric Attributes of Two Native Forage Species According to Water Source Distance in Semiarid Central Grasslands of Argentina

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Phyton-International Journal of Experimental Botany 2024年第8期93卷 2063-2074页

作者： Carla Etel Suárez María Sol Rossini Ernesto Francisco Atilio Morici Héctor Daniel Esterlich Laboratorio de Ecología en Ambientes Semiáridos Ecología VegetalFacultad de AgronomíaUNLPamSanta Rosa6300Argentina Facultad de Ciencias Veterinarias UNLPamGeneral Pico6360Argentina Becaria doctoral CONICET APNFacultad de AgronomíaUNLPamSanta Rosa6300Argentina

The semiarid grasslands of Argentina’s central region have been modified by domestic livestock grazing,both in their composition and *** increase in the proportion of woody and non-forage species and the decrease in forage species are some of the most evident results of this *** is limited available information about the effect of differential grazing pressures on morphometric attributes of native species,and it also depends on the life histories of the species in this *** objective of this work was to evaluate some morphometric aspects in the grasses Poa ligularis Nees ex Steud and Piptochaetium napostaense(Speg.).Hack according to distance from the water source in communities in the central semiarid region of *** study area included areas of low grassland,golden forests,and secondary forests in grasslands(6 fields with 9 paddocks).Grazing pressure was established based on the distance to the water source,so sampling areas were designated near the water source(grazing pressure is greater)and far from the water source(grazing pressure light)in each of the *** both species,specimens were selected at random,and the following attributes were measured:crown diameter at ground level(cm),burial depth(cm),average tiller weight per plant(***^(−1)),and the density of tillers per unit of crown surface(***^(−2)crown).The morphometric attributes evaluated showed differences according to the distance to the watering hole and in the different *** species presented similar behaviors for the *** were significant differences in the depth of burial and the average weight of tillers per plant,being greater in the areas close to the water *** the distance to the watering hole,there were no significant differences in crown diameter and tiller density,but the highest values were recorded for the former near the watering hole and for the second far from the watering *** pastures with low

关键词： Grazing pressure tiller density tiller weight crown burial depth Poa ligularis Piptochaetium napostaense

Analysis of Modeling the Influence of Electromagnetic Fields Radiated by Industrial Static Converters and Impacts on Operators Using Maxwell’s Equations

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Open Journal of Applied Sciences 2024年第8期14卷 2320-2350页

作者： Anthony Bassesuka Sandoka Nzao Tuka Biaba Samuel Garcia Obed Bitala Arsène Kasereka Kibwana Emmanuel Ndaye Kibuayi ISTA Kinshasa Electrical Engineering Kinshasa Democratic Republic of Congo doctoral School of ISTA Kinshasa Complementary Master in Science and Technology/Electrical Engineering Electrotechnical Option Kinshasa Democratic Republic of Congo ISTA Kinshasa doctoral School in Science and Technology Electronics Option Kinshasa Democratic Republic of Congo

The study of Electromagnetic Compatibility is essential to ensure the harmonious operation of electronic equipment in a shared environment. The basic principles of Electromagnetic Compatibility focus on the ability of devices to withstand electromagnetic disturbances and not produce disturbances that could affect other systems. Imperceptible in most work situations, electromagnetic fields can, beyond certain thresholds, have effects on human health. The objective of the present article is focused on the modeling analysis of the influence of geometric parameters of industrial static converters radiated electromagnetic fields using Maxwell’s equations. To do this we used the analytical formalism for calculating the electromagnetic field emitted by a filiform conductor, to model the electromagnetic radiation of this device in the spatio-temporal domain. The interactions of electromagnetic waves with human bodies are complex and depend on several factors linked to the characteristics of the incident wave. To model these interactions, we implemented the physical laws of electromagnetic wave propagation based on Maxwell’s and bio-heat equations to obtain consistent results. These obtained models allowed us to evaluate the spatial profile of induced current and temperature of biological tissue during exposure to electromagnetic waves generated by this system. The simulation 2D results obtained from computer tools show that the temperature variation and current induced by the electromagnetic field can have a very significant influence on the life of biological tissue. The paper provides a comprehensive analysis using advanced mathematical models to evaluate the influence of electromagnetic fields. The findings have direct implications for workplace safety, potentially influencing standards and regulations concerning electromagnetic exposure in industrial settings.

关键词： Modeling Electromagnetic Field Power Converters Geometric Parameters Biological Tissue Maxwell Equation Bio-Heat Equation Thermal Model