检索结果-南通市图书馆

Defence Technology（防务技术） 2024年第1期31卷 537-543页

作者： Huang Hailong Mohsen Eskandari Andrey v.savkin Wei Ni The Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic UniversityHong KongChina school of Electrical Engineering and Telecommunications University of New South WalesSydney2052Australia Data61 CSIROAustralia

We consider a scenario where an unmanned aerial vehicle(UAv),a typical unmanned aerial system(UAs),transmits confidential data to a moving ground target in the presence of multiple *** friendly reconfigurable intelligent surfaces(RIss) help to secure the UAv-target communication and improve the energy efficiency of the *** formulate an optimization problem to minimize the energy consumption of the UAv,subject to the mobility constraint of the UAv and that the achievable secrecy rate at the target is over a given *** present an online planning method following the framework of model predictive control(MpC) to jointly optimize the motion of the UAv and the configurations of the *** effectiveness of the proposed method is validated via computer simulations.

关键词： Unmanned aerial systems(UAss) Unmanned aerial vehicle(UAv) Communication security Eaves-dropping Reconfigurable intelligent surfaces(RIs) Autonomous navigation and placement path planning Model predictive control

LeafspotNet:A deep learning framework for detecting leaf spot disease in jasmine plants

在线全文

学校读者我要写书评

暂无评论

Artificial Intelligence in Agriculture 2024年第2期12卷 1-18页

作者： shwetha v Arnav Bhagwat vijaya Laxmi Department of Electrical and Electronics Engineering Manipal Institute of TechnologyManipalManipal Academy of Higher EducationManipal 576104KarnatakaIndia

Leaf blight spot disease,caused by bacteria and fungi,poses a threat to plant health,leading to leaf discoloration and diminished agricultural *** response,we present a MobileNetv3 based classifier designed for the Jasmine plant,leveraging lightweight Convolutional Neural Networks(CNNs)to accurately identify disease *** model integrates depth wise convolution layers and max pool layers for enhanced feature extraction,focusing on crucial low level features indicative of the *** preprocessing techniques,including data augmentation with Conditional GAN and particle swarm Optimization for feature selection,the classifier achieves robust *** on curated datasets demonstrates an outstanding 97%training accuracy,highlighting its *** world testing with diverse conditions,such as extreme camera angles and varied lighting,attests to the model's resilience,yielding test accuracies between 94%and 96%.The dataset's tailored design for CNN based classification ensures result ***,the model's lightweight classification,marked by fast computation time and reduced size,positions it as an efficient solution for real time *** comprehensive approach underscores the proposed classifier's significance in addressing leaf blight spot dis-ease challenges in commercial crops.

关键词： CNN Detection Leaf CGAN Augmentation Classification swarm optimization Disease detection Tomato leaf Casava leaf

performance and safety Improvement of Induction Motors based on Testing and Evaluation standards

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CEs Transactions on Electrical Machines and systems 2024年第3期8卷 310-318页

作者： Nkosinathi s.Khumalo Ntombizotwa p.Memane Udochukwu B.Akuru Department of Electrical Engineering Tshwane University of TechnologyPretoria 0183South Africa

The induction motor,which converts electrical energy into mechanical energy,has been recognized as the cornerstone of *** rotor of an induction motor can be either a squirrel cage rotor or a wound-type rotor,both existing as magnetless ***-phase squirrel cage induction motors are frequently utilized in industrial drives because they are dependable,have high starting torque,are selfstarting and ***-phase induction motors,on the other hand,are commonly used for small loads such as domestic appliances in form of modest fans,pumps and electric power *** south Africa,there have been reports of fires and explosions resulting in live and property loss because of induction motors that have not been thoroughly tested or are incorrectly labelled in terms of ratings,electrical safety and *** goal of this study is targeted at preventing end-user injuries and failures caused by non-compliant induction motors,by evaluating locally manufactured/imported induction motors based on tests and evaluation from standards(IEC and sANs).The study is conducted using experimental procedures at the Explosion prevention Technology and Rotating Machines(EpT and RM)laboratory,south African Bureau of standards(sABs),south *** main finding from the study shows differences in the nameplate characteristics of various induction motors which could have detrimental effects such as production and operational downtime in their end-use industries,at later stages.

关键词： Compliance Induction motors International Electro-Technical standards(IEC) Nameplate Experimental tests south African National standards(sANs)

synthesis of coral-like structures of pr-Yb co-doped YIG: structural,optical, magnetic and antimicrobial properties

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca p.Araujo Y.Guerra s.Castro-Lopes J.Matilla-Arias Idglan s.de Lima Edson C.silva-Filho Josy A.Osajima F.Guerrero R.pena-Garcia Federal University of piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of piaui Department of PhysicTeresinaPBrazil Federal University of pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDs) spectra and textural properties show corallike structures, peaks associated with pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of pr^(3+) cations favored the activity against s. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

在线全文

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-R.Marquès L.Lancia p.Loiseau p.Forestier-Colleoni M.Tarisien E.Atukpor v.Bagnoud C.Brabetz F.Consoli J.Domange F.Hannachi p.Nicolaï M.salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance Universitéparis-saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GsI Helmholtzzentrum für schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance Universitéparis-saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CsA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CsA.

关键词： acceleration hydrodynamic collision

First evidence for chiral wobbling of triaxial nuclei

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear science and Techniques 2024年第7期35卷 4-7页

作者： s.Frauendorf Department of physics and Astronomy University of Notre DameNotre DameIN 46556USA

Chirality(Greek“handiness”)is a property of many com-plex *** molecules exist in two forms,one being the mirror image of the *** for our hands,it is impossible to make the images identical by a suitable *** two forms are called left-handed and *** have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a *** properties that are insensitive to the geometry are also the *** different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same ***,the geometrical differences between the two species may have other *** two species of the carvon molecule shown in Fig.1 taste quite differently.

关键词： turns Chiral mirror

CoopAI-Route: DRL Empowered Multi-Agent Cooperative system for Efficient Qos-Aware Routing for Network slicing in Multi-Domain sDN

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & sciences 2024年第9期140卷 2449-2486页

作者： Meignanamoorthi Dhandapani v.vetriselvi R.Aishwarya College of Engineering Guindy Anna UniversityChennai600025India

The emergence of beyond 5G networks has the potential for seamless and intelligent connectivity on a global *** slicing is crucial in delivering services for different,demanding vertical applications in this ***-generation applications have time-sensitive requirements and depend on the most efficient routing path to ensure packets reach their intended ***,the existing Ip(Internet protocol)over a multi-domain network faces challenges in enforcing network slicing due to minimal collaboration and information sharing among network *** inter-domain routing methods,like Border Gateway protocol(BGp),cannot make routing decisions based on performance,which frequently results in traffic flowing across congested paths that are never *** address these issues,we propose CoopAI-Route,a multi-agent cooperative deep reinforcement learning(DRL)system utilizing hierarchical software-defined networks(sDN).This framework enforces network slicing in multi-domain networks and cooperative communication with various administrators to find performance-based routes in intra-and ***-Route employs the Distributed Global Topology(DGT)algorithm to define inter-domain Quality of service(Qos)***-Route uses a DRL agent with a message-passing multi-agent Twin-Delayed Deep Deterministic policy Gradient method to ensure optimal end-to-end routes adapted to the specific requirements of network slicing *** evaluation demonstrates CoopAI-Route’s commendable performance in scalability,link failure handling,and adaptability to evolving topologies compared to state-of-the-art methods.

关键词： 6G multi-domain multi-agent routing DRL sDN

Tribological behavior of lubricant-impregnated porous polyimide

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2024年第4期12卷 711-725页

作者： Jinbang LI Ningning ZHOU Janet s.s.WONG school of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China Beijing Key Laboratory of Long-life Technology of precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100029China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

porous materials impregnated with lubricants can be used in conditions where limited lubricant is *** this work,three porous polyimides(ppI)with different densities were ***(pAO)impregnated ppI(ippI)discs were rubbed against steel and sapphire *** operando observations of the ippI-sapphire contacts show that oil is released under an applied load,forming a meniscus around *** at the outlet is created at high sliding *** amount of released oil increases with increasing ppI *** moduli,E*,estimated based on the actual contact size show that trapped oil in ippIs contributes to load *** higher speeds,tribological rehydration of the contact occurs in low density ippI,with that E*rises with *** high density ppIs,high speeds give a constantly high E*which is limited by the viscoelastic properties of the ppI network and possibly the rate of oil *** of ippI-steel contacts is governed by the mechanical properties of the ppI,the flow of the lubricant,and the roughness of the ppI *** low-and medium-density(highly porous,high roughness)ppIs,large amount of oil is released,and lubrication is mainly via lubricant restricted in the contact in the pores and possibly tribological *** high density(low porosity)ppI,with lower roughness,hydrodynamic lubrication is achieved which gives the lowest *** results show that polymeric porous materials for effective lubrication require the optimization of its surface roughness,stiffness,oil flow,and oil retentions.

关键词： polyimide porous material friction mechanism polymer limited lubrication

Distributed Dynamic Load in structural Dynamics by the Impulse-Based Force Estimation Algorithm

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & sciences 2024年第6期139卷 2865-2891页

作者： Yuantian Qin Yucheng Zhang vadim v.silberschmidt College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing210016China Wolfson school of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLE113TUUK

This paper proposes a novel approach for identifying distributed dynamic loads in the time *** polynomial andmodal analysis,the load is transformed intomodal space for coefficient *** allows the distributed dynamic load with a two-dimensional form in terms of time and space to be simultaneously identified in the form of modal force,thereby achieving dimensionality *** Impulse-based Force Estimation Algorithm is proposed to identify dynamic loads in the time ***,the algorithm establishes a recursion scheme based on convolution integral,enabling it to identify loads with a long history and rapidly changing forms over ***,the algorithm introduces moving mean and polynomial fitting to detrend,enhancing its applicability in load *** aforementioned methodology successfully accomplishes the reconstruction of distributed,instead of centralized,dynamic loads on the continuum in the time domain by utilizing acceleration *** validate the effectiveness of the method,computational and experimental verification were conducted.

关键词： Distributed force estimation time domain deconvolution recursion

Higher Grain-Filling Rate in Inferior spikelets of Tolerant Rice Genotype Offset Grain Yield Loss under post-Anthesis High Night Temperatures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rice science 2024年第5期31卷 572-586,I0059-I0061页

作者： Nitin sHARMA Bhupinder sINGH subbaiyan Gopala KRIsHNAN Haritha BOLLINEDI pranab Kumar MANDAL Milan Kumar LAL prakash Kumar JHA p.v.vara pRAsAD Anjali ANAND Division of plant physiology Indian Council of Agricultural Research(ICAR)-Indian Agricultural Research Institute(IARI)New Delhi 110012India Division of Environment science ICAR-IARINew Delhi 110012India Division of Genetics ICAR-IARINew Delhi 110012India ICAR-National Institute for plant Biotechnology New Delhi 110012India Division of Crop physiology and Biochemistry ICAR-National Rice Research InstituteCuttack 753006India Department of plant and soil sciences Mississippi State UniversityStarkvilleMS 39762USA Feed the Future Innovation Lab for Collaborative Research on sustainable Intensification Kansas State UniversityManhattanKS 66506USA Department of Agronomy Kansas State UniversityManhattanKS 66506USA

Increased nighttime respiratory losses decrease the amount of photoassimilates available for plant growth and yield. We hypothesized that the increased respiratory carbon loss under high night temperatures(HNT) could be compensated for by increased photosynthesis during the day following HNT exposure. Two rice genotypes, vandana(HNT-sensitive) and Nagina 22(HNT-tolerant), were exposed to HNT(4 ℃ above the control) from flowering to physiological maturity. They were assessed for alterations in the carbon balance of the source(flag leaf) and its subsequent impact on grain filling dynamics and the quality of spatially differentiated sinks(superior and inferior spikelets). Both genotypes exhibited significantly higher night respiration rates. However, only Nagina 22 compensated for the high respiration rates with an increased photosynthetic rate, resulting in a steady production of total dry matter under HNT. Nagina 22 also recorded a higher grain-filling rate, particularly at 5 and 10 d after flowering, with 1.5- and 4.0-fold increases in the translocation of ^(14)C sugars to the superior and inferior spikelets, respectively. The ratio of photosynthetic rate to respiratory rate on a leaf area basis was negatively correlated with spikelet sterility, resulting in a higher filled spikelet number and grain weight per plant, particularly for inferior grains in Nagina 22. Grain quality parameters such as head rice recovery, high-density grains, and gelatinization temperature were maintained in Nagina 22. An increase in the rheological properties of rice flour starch in Nagina 22 under HNT indicated the stability of starch and its ability to reorganize during the cooling process of product formation. Thus, our study showed that sink adjustments between superior and inferior spikelets favored the growth of inferior spikelets, which helped to offset the reduction in grain weight under HNT in the tolerant genotype Nagina 22.

关键词： high night temperature inferior grain pasting property radiolabeled sugar superior grain