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Nonlinear dynamic modeling of planar moving Timoshenko beam considering non-rigid non-elastic axial effects

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 479-496页

作者： M.ABBASI GAVArI M.r.HOMAEINEZHAD Faculty of Mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and undergoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are derived as a coupled system of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assumed mode method(AMM)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped boundary conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,numerical simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(AMM) nonlinear motion analysis

Evaluation of slope stability through rock mass classification and kinematic analysis of some major slopes along NH-1A from ramban to Banihal, North Western Himalayas

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Journal of rock Mechanics and Geotechnical Engineering 2024年第1期16卷 167-182页

作者： Amit Jaiswal A.k.Verma T.N.Singh Department of Civil and Environmental Engineering Indian Institute of Technology PatnaPatna801106India

The network of Himalayan roadways and highways connects some remote regions of valleys or hill slopes,which is vital for India’s socio-economic *** to natural and artificial factors,frequency of slope instabilities along the networks has been increasing over last few *** of stability of natural and artificial slopes due to construction of these connecting road networks is significant in safely executing these roads throughout the *** rock mass classification methods are generally used to assess the strength and deformability of rock *** study assesses slope stability along the NH-1A of ramban district of North Western *** structurally and non-structurally controlled rock mass classification systems have been applied to assess the stability conditions of 14 *** evaluating the stability of these slopes,kinematic analysis was performed along with geological strength index(GSI),rock mass rating(rMr),continuous slope mass rating(CoSMr),slope mass rating(SMr),and Q-slope in the present *** SMr gives three slopes as completely unstable while CoSMr suggests four slopes as completely *** stability of all slopes was also analyzed using a design chart under dynamic and static conditions by slope stability rating(SSr)for the factor of safety(FoS)of 1.2 and 1 respectively.Q-slope with probability of failure(PoF)1%gives two slopes as stable *** slope angle has been determined based on the Q-slope safe angle equation and SSr design chart based on the *** value ranges given by different empirical classifications were rMr(37-74),GSI(27.3-58.5),SMr(11-59),and CoSMr(3.39-74.56).Good relationship was found among rMr&SSr and rMr&GSI with correlation coefficient(r 2)value of 0.815 and 0.6866,***,a comparative stability of all these slopes based on the above classification has been performed to identify the most critical slope along this road.

关键词： rock mass classification kinematic analysis Slope stability Himalayan road Static and dynamic conditions

Near resonance vibration isolation on a levered-dual response(LEDAr)Coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： T.I.TOLUWALOJU C.k.THEIN D.HALIM Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo China Beacons of Excellence research and Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

The levered-dual response(LEDAr)Coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(rHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEDAr system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio Coulomb damping preload tension/compression isolation band/depth offset potential

Chemical short-range-order induced multiscale strengthening in refractory medium entropy alloys

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Acta Mechanica Sinica 2024年第6期40卷 41-49页

作者： Weizheng Lu Yang Chen Jia Li Peter k.Liaw Qihong Fang State key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha410082China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN37996USA

High/medium entropy alloys(H/MEAs)are generally possible to exhibit chemical short-range order(SrO).However,the complex role of SrO on mechanical properties from nano-scale to meso-scale is still challenging so ***,we study the strengthening mechanism and deformation behavior in a model body-centered-cubic HfNbTa MEA by using atomic-scale molecular dynamics,micro-scale dislocation dynamics,and meso-scale crystal plasticity finite *** SrO inhibits dislocation nucleation at the atomic scale,improving the flow *** SrO-induced ultrastrong local stress fluctuation greatly improves the micro-scale dislocation-based strength by the significant dislocation forest ***,the Ta-rich locally ordered structure leads to an obvious heterogeneous strain and stress partitioning,which forms a strong strain gradient in the adjacent grain interiors and contributes to the strong back-stress-induced strain hardening.

关键词： High/medium entropy alloys Multiscale strengthening Chemical short-range order

Juxtapose of System Performance for Food Calorie Estimation Using IoT and Web-based Indagation

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Journal of Harbin Institute of Technology(New Series) 2024年第1期31卷 54-63页

作者： Anusuya S Sharmila k Department of Computer Science VISTASChennai 600117India Department of Computer Science Dr.MGR Janaki College for WomenChennai 600028India

A rudimentary aspect of human life is the health of an individual,and most commonly the wellbeing is impacted in a colossal manner through the consumption of food. The intake of calories therefore is a crucial aspect that must be meticulously monitored. Various health gremlins can be largely circumvented when there is a substantial balance in the number of calories ingested versus the quantity of calories *** food calorie estimation is a popular domain of research in recent times and is meticulously analyzed through various image processing and machine learning techniques. However,the need to scrutinize and evaluate the calorie estimation through various platforms and algorithmic approaches aids in providing a deeper insight on the bottlenecks involved,and in improvising the bariatric health of an individual. This paper pivots on comprehending a juxtaposed approach of food calorie estimation through the use of employing Convolution Neural Network(CNN)incorporated in Internet of Things(IoT),and using the Django framework in Python,along with query rule-based training to analyze the subsequent actions to be followed post the consumption of food calories in the constructed webpage. The comparative analysis of the food calorie estimate implemented in both platforms is analyzed for the swiftness of identification,error rate and classification accuracy to appropriately determine the optimal method of use. The simulation results for IoT are carried out using the raspberry Pi4B model,while the Anaconda prompt is used to run the server holding the web page.

关键词： food calorie estimation convolution neural network Django framework internet of things raspberry Pi

Large-scale genome-wide SNP analysis reveals the rugged(and ragged)landscape of global ancestry,phylogeny,and demographic history in chicken breeds

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 324-340页

作者： Natalia V.DEMENTIEVA Yuri S.SHCHErBAkOV Olga I.STANISHEVSkAYA Anatoly B.VAkHrAMEEV Tatiana A.LArkINA Artem P.DYSIN Olga A.NIkOLAEVA Anna E.rYABOVA Anastasiia I.AZOVTSEVA Olga V.MITrOFANOVA Grigoriy k.PEGLIVANYAN Natalia r.rEINBACH Darren k.GrIFFIN Michael N.rOMANOV russian research Institute of Farm Animal Genetics and Breeding-Branch of the L.k.Ernst Federal research Centre for Animal Husbandry.Pushkin St.Petersburg196601Russia School of Biosciences University of KentCanterburyCT27NJUK L.k.Ernst Federal research Center for Animal Husbandry DubrovitsyPodolskMoscow Oblast142132Russia

The worldwide chicken gene pool encompasses a remarkable,but shrinking,number of divergently selected breeds of diverse *** study was a large-scale genome-wide analysis of the landscape of the complex molecular architecture,genetic variability,and detailed structure among 49 *** populations represent a significant sample of the world's chicken breeds from Europe(russia,Czech republic,France,Spain,Uk,etc.),Asia(China),North America(USA),and Oceania(Australia).Based on the results of breed genotyping using the Illumina 60k single nucleotide polymorphism(SNP)chip,a bioinformatic analysis was carried *** included the calculation of heterozygosity/homozygosity statistics,inbreeding coefficients,and effective population *** also included assessment of linkage disequilibrium and construction of phylogenetic *** multidimensional scaling,principal component analysis,and ADMIXTUrE-assisted global ancestry analysis,we explored the genetic structure of populations and subpopulations in each *** overall 49-population phylogeny analysis was also performed,and a refined evolutionary model of chicken breed formation was proposed,which included egg,meat,dual-purpose types,and ambiguous *** a large-scale survey of genetic resources in poultry farming using modern genomic methods is of great interest both from the viewpoint of a general understanding of the genetics of the domestic chicken and for the further development of genomic technologies and approaches in poultry *** general,whole genome SNP genotyping of promising chicken breeds from the worldwide gene pool will promote the further development of modern genomic science as applied to poultry.

关键词： Chicken genome diversity Single nucleotide polymorphism(SNP)analysis Gene pool Global ancestry Phylogeny Demographic history

5G resource Allocation Using Feature Selection and Greylag Goose Optimization Algorithm

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Computers, Materials & Continua 2024年第7期80卷 1179-1201页

作者： Amel Ali Alhussan S.k.Towfek Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Computer Science and Intelligent Systems research Center BlacksburgVA 24060USA

In the contemporary world of highly efficient technological development,fifth-generation technology(5G)is seen as a vital step forward with theoretical maximum download speeds of up to twenty gigabits per second(Gbps).As far as the current implementations are concerned,they are at the level of slightly below 1 Gbps,but this allowed a great leap forward from fourth generation technology(4G),as well as enabling significantly reduced latency,making 5G an absolute necessity for applications such as gaming,virtual conferencing,and other interactive electronic *** of this change are not limited to connectivity alone;it urges operators to refine their business strategies and offers users better and improved digital *** essential factor is optimization and the application of artificial intelligence throughout the general arrangement of intricate and detailed 5G *** Binary Greylag Goose Optimization(bGGO)to achieve a significant reduction in the feature set while maintaining or improving model performance,leading to more efficient and effective 5G network management,and Greylag Goose Optimization(GGO)increases the efficiency of the machine ***,the model performs and yields more accurate *** work proposes a new method to schedule the resources in the next generation,5G,based on a feature selection using GGO and a regression model that is an ensemble of k-Nearest Neighbors(kNN),Gradient Boosting,and Extra Trees *** ensemble model shows better prediction performance with the coefficient of determination r squared value equal *** proposed framework is supported by several Statistical analyses,such as theWilcoxon signed-rank *** of the benefits of this study are the introduction of new efficient optimization algorithms,the selection of features and more reliable ensemble models which improve the efficiency of 5G technology.

关键词： Optimization ensemble learning 5G technology artificial intelligence greylag goose optimization ANOVA test

Physical properties and maximum allowable mass-radius relation of complexity-free compact stellar objects within modified f(r,T)gravity formalism

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Chinese Physics C 2024年第7期48卷 273-288页

作者： M.k.Jasim S.k.Maurya Abdelghani Errehymy Ali khalid Jassim kottakkaran Sooppy Nisar Abdel-Haleem Abdel-Aty Department of Mathematical and Physical Sciences College of Arts and SciencesUniversity of NizwaNizwa 616Sultanate of Oman Astrophysics research Centre School of MathematicsStatistics and Computer ScienceUniversity of KwaZulu-NatalPrivate Bag X54001Durban 4000South Africa Electrical Engineering Department College of EngineeringMustansiriyah UniversityBaghdadIraq Department of Mathematics College of Science and Humanities in AlkharjPrince Sattam bin Abdulaziz UniversityAl KharjSaudi Arabia Department of Physics College of SciencesUniversity of BishaP.O.Box 344Bisha 61922Saudi Arabia

This paper investigates the physical properties and predicted radii of compact stars generated by the Tolman-IV complexity-free model within the background of modified gravity theory,particularly the f(r,T)-gravity theory,under complexity formalism for a spherically symmetric spacetime proposed by ***[Phys rev D 97:044010,2018].By solving the resulting set of differential equations,we obtain the explicit forms of the energy-momentum(EM)tensor components,including the density,radial pressure,and tangential *** influence of the parameterχon various physical properties of the star is thoroughly *** model undergoes a series of rigorous tests to determine its physical *** findings indicate that the model exhibits regularity,stability,and a surface with vanishing *** boundary of this surface is determined by carefully selecting the parameter *** complexity method employed in f(r,T)gravity offers an interesting approach for developing astrophysical models that are consistent with observable events as demonstrated by recent *** this regard,we use observational data from the GW190814 event,detected by the LIGO and Virgo observatories,to investigate the validity of the Tolman-IV model in f(r,T)*** analysis includes comparing the model's predictions with the observed characteristics of the compact object involved in the *** addition,data from two-millisecond pulsars,PSr J1614-2230 and PSr J0952-0607,are incorporated to further constrain the theoretical ***,we present a diagram depicting the relationship between the total mass and radius of the compact object candidates for different values ofχ.

关键词： complexity modified gravity compact Stars

Gastric cystica profunda:Another indication for minimally invasive endoscopic resection techniques?

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World Journal of Gastroenterology 2024年第27期30卷 3278-3283页

作者： Harjot k Bedi Douglas Motomura Neal Shahidi Department of Medicine University of British ColumbiaVancouver V6Z 2K5BCCanada

Gastric cancer presents a significant global health burden,as it is the fifth most common malignancy and fourth leading cause of cancer mortality *** in incidence rates across regions underscores the multifactorial etiology of this *** overall 5-year survival rate remains low despite advances in its diagnosis and *** surgical gastrectomy was previously standard-of-care,endoscopic resection techniques,including endoscopic mucosal resection and endoscopic submucosal dissection(ESD)have emerged as effective alternatives for early *** to surgical resection,endoscopic resection techniques have comparable 5-year survival rates,reduced treatment-related adverse events,shorter hospital stays and lower *** also enables en bloc resection,thus affording organ-sparing curative endoscopic resection for early *** this editorial,we comment on the recent publication by Geng et al regarding gastric cystica profunda(GCP).GCP is a rare gastric pseudotumour with the potential for malignant *** presents a diagnostic challenge due to its nonspecific clinical manifestations and varied endoscopic *** are several gaps in the literature regarding the diagnosis and management of GCP which warrants further research to standardize patient *** in endoscopic resection techniques offer promising avenues for GCP and early gastric cancers.

关键词： Early gastric cancer Endoscopy Endoscopic submucosal dissection Gastric cystica profunda