Text classification is a challenging task in the field of Natural Language Processing (NLP), and significant progress has been made using deep learning methods. Traditional deep-learning approaches for text classifica...
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Human action recognition(HAR) has important applications, including video retrieval, entertainment, autonomous navigation systems, and visual surveillance systems [1]. Unfortunately, accurate and efficient HAR remains...
Human action recognition(HAR) has important applications, including video retrieval, entertainment, autonomous navigation systems, and visual surveillance systems [1]. Unfortunately, accurate and efficient HAR remains a challenging task in the field of computer vision because its modeling and characteristic representation belong to threedimensional space-time instead of common two-dimensional space [2].
With the continuous improvement of photovoltaic efficiency in the organic photovoltaic(OPV),interface engineering has emerged as a pivotal issue in their practical ***,the robust crystallinity of small molecule electr...
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With the continuous improvement of photovoltaic efficiency in the organic photovoltaic(OPV),interface engineering has emerged as a pivotal issue in their practical ***,the robust crystallinity of small molecule electron transport layers(ETLs) and the poor film-forming abilities of conjugated polymer ETLs are a huge obstacle in this ***,an innovative and efficient nonconjugated polymer ETL,namely PNDI-SO,which contains polar cationic segments for solubility and conjugated units for efficient charge transport in stable OPV cells,is *** with suitable energy levels and excellent electron extraction capabilities,PNDI-SO-based OPV cells attain a power conversion efficiency(PCE) of 18.54%.Furthermore,compared with conventional OPV cells utilizing PFN-Br or PDINN,PNDI-SO substantially enhances long-term stability under continuous illumination,evidenced by a T80 lifetime(signifying retention of 80% of initial performance) exceeding 1250 ***,through scanning electron microscope,we verified that PNDI-SO achieves a harmonious balance between film-forming ability and charge transport properties for ETL,enabling the blade-coating OPV based on PBDB-TF:BTP-eC9 to achieve a PCE of 17.47%.These results suggest the potential of PNDI-SO as a promising interface material for industrial printing applications in OPV fabrication.
作者:
高旭峰王琦张世杰洪瑞金张大伟Shanghai Key Laboratory of Modern Optic Systems
Engineering Research Center of Optical Instrument and SystemMinistry of Education and Shanghai Key Laboratory of Modern Optical SystemsSchool of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China
Color filters in different surroundings inherently suffer from angular sensitivity,which hinders their practical ***,we present an angle-insensitive plasmonic filter that can produce different color responses to diffe...
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Color filters in different surroundings inherently suffer from angular sensitivity,which hinders their practical ***,we present an angle-insensitive plasmonic filter that can produce different color responses to different surrounding *** color filters are based on a two-dimensional periodically and randomly distributed silver nanodisk array on a silica *** proposed plasmonic color filters not only produce bright colors by altering the diameter of the Ag nanodisk,but also achieve continuous color palettes by changing the surrounding *** to the weak coupling between the metallic nanodisks,the plasmonic color filters can enable good incident angle-insensitive properties(up to 30°).The strategy presented here could exhibit robust and promising applicability in anti-counterfeiting and imaging technologies.
This paper presents a distributed scheme with limited communications, aiming to achieve cooperative motion control for multiple omnidirectional mobile manipulators(MOMMs).The proposed scheme extends the existing singl...
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This paper presents a distributed scheme with limited communications, aiming to achieve cooperative motion control for multiple omnidirectional mobile manipulators(MOMMs).The proposed scheme extends the existing single-agent motion control to cater to scenarios involving the cooperative operation of MOMMs. Specifically, squeeze-free cooperative load transportation is achieved for the end-effectors of MOMMs by incorporating cooperative repetitive motion planning(CRMP), while guiding each individual to desired poses. Then, the distributed scheme is formulated as a time-varying quadratic programming(QP) and solved online utilizing a noise-tolerant zeroing neural network(NTZNN). Theoretical analysis shows that the NTZNN model converges globally to the optimal solution of QP in the presence of noise. Finally, the effectiveness of the control design is demonstrated by numerical simulations and physical platform experiments.
With the evolution of next-generation communication networks,ensuring robust Core Network(CN)architecture and data security has become *** paper addresses critical vulnerabilities in the architecture of CN and data se...
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With the evolution of next-generation communication networks,ensuring robust Core Network(CN)architecture and data security has become *** paper addresses critical vulnerabilities in the architecture of CN and data security by proposing a novel framework based on blockchain technology that is specifically designed for communication *** centralized network architectures are vulnerable to Distributed Denial of Service(DDoS)attacks,particularly in roaming scenarios where there is also a risk of private data leakage,which imposes significant operational *** address these issues,we introduce the Blockchain-Enhanced Core Network Architecture(BECNA)and the Secure Decentralized Identity Authentication Scheme(SDIDAS).The BECNA utilizes blockchain technology to decentralize data storage,enhancing network security,stability,and reliability by mitigating Single Points of Failure(SPoF).The SDIDAS utilizes Decentralized Identity(DID)technology to secure user identity data and streamline authentication in roaming scenarios,significantly reducing the risk of data breaches during cross-network *** framework employs Ethereum,free5GC,Wireshark,and UERANSIM tools to create a robust,tamper-evident system model.A comprehensive security analysis confirms substantial improvements in user privacy and network *** results indicate that our approach enhances communication CNs security and reliability,while also ensuring data security.
Avatars, as promising digital representations and service assistants of users in Metaverses, can enable drivers and passengers to immerse themselves in 3D virtual services and spaces of UAV-assisted vehicular Metavers...
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Avatars, as promising digital representations and service assistants of users in Metaverses, can enable drivers and passengers to immerse themselves in 3D virtual services and spaces of UAV-assisted vehicular Metaverses. However, avatar tasks include a multitude of human-to-avatar and avatar-to-avatar interactive applications, e.g., augmented reality navigation,which consumes intensive computing resources. It is inefficient and impractical for vehicles to process avatar tasks locally. Fortunately, migrating avatar tasks to the nearest roadside units(RSU)or unmanned aerial vehicles(UAV) for execution is a promising solution to decrease computation overhead and reduce task processing latency, while the high mobility of vehicles brings challenges for vehicles to independently perform avatar migration decisions depending on current and future vehicle status. To address these challenges, in this paper, we propose a novel avatar task migration system based on multi-agent deep reinforcement learning(MADRL) to execute immersive vehicular avatar tasks dynamically. Specifically, we first formulate the problem of avatar task migration from vehicles to RSUs/UAVs as a partially observable Markov decision process that can be solved by MADRL algorithms. We then design the multi-agent proximal policy optimization(MAPPO) approach as the MADRL algorithm for the avatar task migration problem. To overcome slow convergence resulting from the curse of dimensionality and non-stationary issues caused by shared parameters in MAPPO, we further propose a transformer-based MAPPO approach via sequential decision-making models for the efficient representation of relationships among agents. Finally, to motivate terrestrial or non-terrestrial edge servers(e.g., RSUs or UAVs) to share computation resources and ensure traceability of the sharing records, we apply smart contracts and blockchain technologies to achieve secure sharing management. Numerical results demonstrate that the proposed approach
This paper studies a geometric attitude tracking control problem of quadrotor unmanned aerial vehicles (UAVs) with adaptive extended state observers (AESOs). Through coordinate transformation, the error dynamic of AES...
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We propose an approach for generating robust two-dimensional(2D)vortex clusters(VCs)in a Rydberg atomic system by utilizing parity-time(PT)symmetric optical Bessel *** show that the system supports novel multicore VCs...
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We propose an approach for generating robust two-dimensional(2D)vortex clusters(VCs)in a Rydberg atomic system by utilizing parity-time(PT)symmetric optical Bessel *** show that the system supports novel multicore VCs with four and eight cores,corresponding to topological charges 2 and 4,*** stability of these VCs can be dynamically adjusted through the manipulation of the gain-loss component,Kerr nonlinearities,and the degree of nonlocality inherent in the Rydberg *** VCs are confined within the first lattice well of the Bessel potential,and both the power and width of lights undergo a quasi-periodic breathing phenomenon,which is attributed to the power exchange between the light fields and Bessel *** self-attractive and self-repulsive Kerr interactions can sustain robust VCs within this *** insights presented here not only facilitate the creation and manipulation of 2D VCs through PT-symmetric potentials but also pave the way for potential applications in optical information processing and transmission.
Electrochemical water splitting,as an effective sustainable and eco-friendly energy conversion strategy,can produce high-purity hydrogen(H_(2))and oxygen(O_(2))via hydrogen evolution reaction(HER)and oxygen evolution ...
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Electrochemical water splitting,as an effective sustainable and eco-friendly energy conversion strategy,can produce high-purity hydrogen(H_(2))and oxygen(O_(2))via hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),respectively,altering the nonrenewable fossil ***,La_(0.6)Sr_(0.4)CoO_(3)perovskite oxide nanoparticles with an orthorhombic phase were synthesized within 2 min in a one-step reaction,using a rapid and efficient high-temperature shock(HTS)***,the as-prepared La_(0.6)Sr_(0.4)CoO_(3)with orthorhombic phase(HTS-2)exhibited better OER and HER performance than the hexagonal phase counterpart prepared using the traditional muffle furnace calcination *** electrocatalytic performance enhancement of orthorhombic La_(0.6)Sr_(0.4)CoO_(3)can be attributed to the novel orthorhombic structure,such as confined strontium segregation,a higher percentage of highly oxidative oxygen species,and more active sites on the *** facile and rapid synthesis technique shows great potential for the rational design and crystal phase engineering of nanocatalysts.
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