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Chiral forces in longitudinally invariant dielectric photonic waveguides

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Photonics Research 2024年第3期12卷 431-443页

作者： JOSeP MARTÍNeZ-ROMeU IAGO diez SeBASTIAN GOLAT FRANCISCO J.RODRÍGUeZ-FORTUÑO ALeJANDRO MARTÍNeZ Nanophotonics Technology Center Universitat Politècnica de ValènciaValencia 46022Spain Department of Physics King’s College LondonLondon WC2R 2LSUK

We calculate numerically the optical chiral forces in rectangular cross-section dielectric waveguides for potential enantiomer *** study considers force strength and time needed for separating chiral nanoparticles,mainly via quasi-Te guided modes at short wavelengths(405 nm)and the 90°-phase-shifted combination of quasi-Te and quasi-TM modes at longer wavelengths(1310 nm).Particle tracking simulations show successful enantiomer separation within two *** results suggest the feasibility of enantiomeric separation of nanoparticles displaying sufficient chirality using simple silicon photonic integrated circuits,with wavelength selection based on the nanoparticle size.

关键词： dielectric forces quasi

Depression Intensity Classification from Tweets Using Fast Text Based Weighted Soft Voting ensemble

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Computers, Materials & Continua 2024年第2期78卷 2047-2066页

作者： Muhammad Rizwan Muhammad Faheem Mushtaq Maryam Rafiq Arif Mehmood Isabel de la Torre.diez Monica Gracia Villar Helena Garay Imran Ashraf Department of Artificial Intelligence The Islamia University of BahawalpurBahawalnagar63100Pakistan Department of Information Technology Khwaja Fareed University of Engineering and ITRYKhan64200Pakistan Department of Computer Science&Information Technology The Islamia University of BahawalpurBahawalnagar63100Pakistan Department of Signal Theory and Communications and Telematic engineering Unviersity of ValladolidPaseo de Belén 15Valladolid47011Spain Faculty of Social Science and Humanities Universidad Europea del Atlántico Isabel Torres 21Santander39011Spain Department of Project Management Universidad Internacional IberoamericanaCampeche24560México Fundación Universitaria Internacional de Colombia Bogotá111611Colombia Universidad Internacional Iberoamericana AreciboPuerto Rico00613USA Universidade Internacional do Cuanza Cuito46703Angola Department of Information and Communication engineering Yeungnam UniversityGyeongsan38541South Korea

Predicting depression intensity from microblogs and social media posts has numerous benefits and applications,including predicting early psychological disorders and stress in individuals or the general public.A major challenge in predicting depression using social media posts is that the existing studies do not focus on predicting the intensity of depression in social media texts but rather only perform the binary classification of depression and moreover noisy data makes it difficult to predict the true depression in the social media *** study intends to begin by collecting relevant Tweets and generating a corpus of 210000 public tweets using Twitter public application programming interfaces(APIs).A strategy is devised to filter out only depression-related tweets by creating a list of relevant hashtags to reduce noise in the ***,an algorithm is developed to annotate the data into three depression classes:‘Mild,’‘Moderate,’and‘Severe,’based on International Classification of Diseases-10(ICD-10)depression diagnostic *** baseline classifiers are applied to the annotated dataset to get a preliminary idea of classification performance on the *** FastText-based model is applied and fine-tuned with different preprocessing techniques and hyperparameter tuning to produce the tuned model,which significantly increases the depression classification performance to an 84%F1 score and 90%accuracy compared to ***,a FastText-based weighted soft voting ensemble(WSVe)is proposed to boost the model’s performance by combining several other classifiers and assigning weights to individual models according to their individual *** proposed WSVe outperformed all baselines as well as FastText alone,with an F1 of 89%,5%higher than FastText alone,and an accuracy of 93%,3%higher than FastText *** proposed model better captures the contextual features of the relatively small sample class and aids in the detection of

关键词： Depression classification deep learning FastText machine learning

electrochemical Realization of 3D Interconnected MoS3/PPy Nanowire Frameworks as Sulfur-equivalent Cathode Materials for Li-S Batteries

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energy & environmental Materials 2024年第2期7卷 13-21页

作者： Hongtao Yu Andreas Siebert Shilin Mei Raul Garcia-diez Roberto Félix Ting Quan Yaolin Xu Johannes Frisch Regan G.Wilks Marcus B?r Chun Pei Yan Lu Department for electrochemical energy Storage Helmholtz-Zentrum Berlin für Materialien und Energie Gmb H (HZB) Guangdong Province Key Laboratory of Durability for Marine Civil engineering School of Civil Engineering Shenzhen University Department of Interface Design HZB energy Materials In-Situ Laboratory Berlin (eMIL) Helmholtz-Institute erlangen-Nürnberg for Renewable energy (HI eRN) Department of Chemistry and Pharmacy Friedrich-Alexander-Universit?t Erlangen-Nürnberg Institute of Chemistry University of Potsdam

The development of freestanding and binder-free electrode is an effective approach to perform the inherent capacity of active materials and promote the mechanism study by minimizing the interference from additives. Herein, we construct a freestanding cathode composed of MoS3/PPy nanowires（NWs） deposited on porous nickel foam（NF）(MoS3/PPy/NF) through electrochemical methods, which can work efficiently as sulfur-equivalent cathode material for Li-S batteries. The structural stability of the MoS3/PPy/NF cathode is greatly enhanced due to its significant tolerance to the volume expansion of MoS3during the lithiation process,which we ascribe to the flexible 3D framework of PPy NWs, leading to superior cycling performance compared to the bulk-MoS3/NF reference. eliminating the interference of binder and carbon additives, the evolution of the chemical and electronic structure of Mo and S species during the discharge/charge was studied by X-ray absorption near-edge spectroscopy（XANeS）. The formation of lithium polysulfides was excluded as the driving cathode reaction mechanism, suggesting the great potential of MoS3as a promising sulfur-equivalent cathode material to evade the shuttle effect for Li-S batteries. The present study successfully demonstrates the importance of structural design of freestanding electrode enhancing the cycling performances and revealing the corresponding mechanisms.

关键词： 3D-Network electrochemical lithium-sulfur battery MoS3 PPy

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTLU İsmail e.KILIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

CLASSIFICATIONS OF DUPIN HYPeRSURFACeS IN LIe SPHeRe GeOMeTRY

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Acta Mathematica Scientia 2024年第1期44卷 1-36页

作者： Thomas e.CeCIL Department of Mathematics and Computer Science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in S^(n)(or R^(n))that have been obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of S^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

FSCIL-eACA: Few-Shot Class-Incremental Learning Network Based on embedding Augmentation and Classifier Adaptation for Image Classification

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Chinese Journal of electronics 2024年第1期33卷 139-152页

作者： Ruru ZHANG Haihong e Meina SONG School of Computer Science Beijing University of Posts and Telecommunications education Department Information Network engineering Research Center Beijing University of Posts and Telecommunications

The ability to learn incrementally is critical to the long-term operation of AI systems. Benefiting from the power of few-shot class-incremental learning(FSCIL), deep learning models can continuously recognize new classes with only a few samples. The difficulty is that limited instances of new classes will lead to overfitting and exacerbate the catastrophic forgetting of the old classes. Most previous works alleviate the above problems by imposing strong constraints on the model structure or parameters, but ignoring embedding network transferability and classifier adaptation(CA), failing to guarantee the efficient utilization of visual features and establishing relationships between old and new classes. In this paper, we propose a simple and novel approach from two perspectives: embedding bias and classifier bias. The method learns an embedding augmented(eA) network with cross-class transfer and class-specific discriminative abilities based on self-supervised learning and modulated attention to alleviate embedding bias. Based on the adaptive incremental classifier learning scheme to realize incremental learning capability,guiding the adaptive update of prototypes and feature embeddings to alleviate classifier bias. We conduct extensive experiments on two popular natural image datasets and two medical datasets. The experiments show that our method is significantly better than the baseline and achieves state-of-the-art results.

关键词： Training Adaptation models Visualization Image recognition Prototypes Self-supervised learning Power capacitors

Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： R Gharaei e Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and Guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the Guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations

event-triggered H_(∞) consensus control for input-constrained multi-agent systems via reinforcement learning

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Control Theory and Technology 2024年第1期22卷 25-38页

作者： Jinxuan Zhang Chang-e Ren College of Information engineering Capital Normal UniversityBeijing100089China

This article presents an event-triggered H_(∞) consensus control scheme using reinforcement learning (RL) for nonlinear second-order multi-agent systems (MASs) with control constraints. First, considering control constraints, the constrained H_(∞) consensus problem is transformed into a multi-player zero-sum game with non-quadratic performance functions. Then, an event-triggered control method is presented to conserve communication resources and a new triggering condition is developed for each agent to make the triggering threshold independent of the disturbance attenuation level. To derive the optimal controller that can minimize the cost function in the case of worst disturbance, a constrained Hamilton–Jacobi–Bellman (HJB) equation is defined. Since it is difficult to solve analytically due to its strongly non-linearity, reinforcement learning (RL) is implemented to obtain the optimal controller. In specific, the optimal performance function and the worst-case disturbance are approximated by a time-triggered critic network;meanwhile, the optimal controller is approximated by event-triggered actor network. After that, Lyapunov analysis is utilized to prove the uniformly ultimately bounded (UUB) stability of the system and that the network weight errors are UUB. Finally, a simulation example is utilized to demonstrate the effectiveness of the control strategy provided.

关键词： H_(∞)optimal control Input constrains Multi-agent systems(MASs) Reinforcement learning(RL)

Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied Mathematics and Mechanics(english edition) 2024年第4期45卷 633-648页

作者： e.GHAVANLOO S.eL-BORGI School of Mechanical engineering Shiraz UniversityShiraz 71963-16548Iran Mechanical engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(MMS)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPM for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPM) method of multiple scales(MMS) dispersion phase velocity