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Dual-channel tunable multipolarization adapted terahertz spatiotemporal vortices generating device

光子学研究（英文） 2025年第5期13卷 1408-1418页

作者： FANGZE DENG KE MA YUMENG MA XIANG HOU ZHIHUA HAN YUCHAO LI KEKE CHENG YANSHENG SHAO CHENGLONG WANG MENG LIU HUIYUN ZHANG YUPING ZHANG Qingdao Key Laboratory of Terahertz Technology College of Electronic and Information EngineeringShandong University of Science and TechnologyQingdao 266590China

Spatiotemporal optical vortices(STOVs)exhibit characteristics of transverse orbital angular momentum(OAM)that is perpendicular to the direction of pulse propagation,indicating significant potential for diverse *** this study,we employ vanadium dioxide and photonic crystal plates to design tunable transreflective dual-channel terahertz(THz)spatiotemporal vortex generation devices that possess multipolarization *** the reflection channel,we achieve active tunability of the topological dark lines by utilizing circularly polarized light,based on the topological dark phenomenon,and observe variations in the number of singularities across the parameter space from different observational *** the transmission channel,we generate independent vortex singularities using linearly polarized *** multifunctional terahertz device offers a novel approach for the generation and active tuning of spatiotemporal vortices.

关键词： terahertz device multi adapted dual-channel generating polarization spatiotemporal tunable vortices

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Layer-Wise Learning Rate Optimization for Task-Dependent Fine-Tuning of Pre-Trained Models: An Evolutionary Approach

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ACM Transactions on Evolutionary Learning and Optimization 2024年第4期4卷 1-23页

作者： Bu, Chenyang Liu, Yuxin Huang, Manzong Shao, Jianxuan Ji, Shengwei Luo, Wenjian Wu, Xindong Key Laboratory of Knowledge Engineering with Big Data Ministry of Education and School of Computer Science and Information Engineering Hefei University of Technology Hefei China School of Artificial Intelligence and Big Data Hefei University Hefei China Guangdong Provincial Key Laboratory of Novel Security Intelligence Technologies School of Computer Science and Technology Harbin Institute of Technology Shenzhen China

The superior performance of large-scale pre-Trained models, such as Bidirectional Encoder Representations from Transformers (BERT) and Generative Pre-Trained Transformer (GPT), has received increasing attention in both academic and industrial research and has become one of the current research hotspots. A pre-Trained model refers to a model trained on large-scale unlabeled data, whose purpose is to learn general language representation or features for fine-Tuning or transfer learning in subsequent tasks. After pre-Training is complete, a small amount of labeled data can be used to fine-Tune the model for a specific task or domain. This two-stage method of "pre-Training+fine-Tuning"has achieved advanced results in natural language processing (NLP) tasks. Despite widespread adoption, existing fixed fine-Tuning schemes that adapt well to one NLP task may perform inconsistently on other NLP tasks given that different tasks have different latent semantic structures. In this article, we explore the effectiveness of automatic fine-Tuning pattern search for layer-wise learning rates from an evolutionary optimization perspective. Our goal is to use evolutionary algorithms to search for better task-dependent fine-Tuning patterns for specific NLP tasks than typical fixed fine-Tuning patterns. Experimental results on two real-world language benchmarks and three advanced pre-Training language models show the effectiveness and generality of the proposed framework. © 2024 held by the owner/author(s).

关键词： Semantics

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Improving aircraft nose wheel steering stability based on control continuation method

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science China(Technological sciences) 2025年第3期68卷 258-277页

作者： Qiaozhi YIN Dexu KONG Jiawei WANG Hong NIE Xiaohui WEI National Key Laboratory of Helicopter Aeromechanics Nanjing210016China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing210016China Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing210016China AVIC Nanjing Engineering Institute of Aircraft Systems Nanjing211106China

Aircraft steering instability during the taxiing process sometimes occurs resulting from the unstable bifurcation phenomena of the nonlinear steering dynamic system,which may lead to severe *** this study,the control parameter design of an aircraft nose wheel steering control system based on the control continuation method is proposed to reduce the number of unstable bifurcation points and enlarge the system stable region area in a certain parameter ***,the aircraft turning performance can be improved ***,a nonlinear aircraft rollout dynamic model is constructed,and the aircraft ground steering bifurcation characteristics are obtained under the open-loop steering control ***,the bifurcation performances under three closed-loop nose wheel steering controllers based on the feedback control method are compared,and the control parameter of the quadratic nonlinear controller with a better bifurcation control effect is selected as a second bifurcation parameter to analyze the directional system stability via two-parameter bifurcation ***,the influence of a crosswind on the aircraft ground steering bifurcation performance is studied for various control parameter ***,the control effects of a traditional proportional-integral-derivative(PID)nose wheel steering control law and the designed feedback controller are compared and ***,a semi-physical experiment of the aircraft nose wheel steering system is carried out,and different control parameter values are selected for test verification,which can further verify the control effect of the designed nonlinear feedback *** results indicate that the feedback control method is unable to vary the system bifurcation types,but appropriate control parameter design can effectively shrink the system instability region and even eliminate the unstable Hopf bifurcation points under some specific working conditions,improving the aircraft ground turning stability re

关键词： aircraft taxiing dynamics and stability nose wheel steering control system control continuation steering bifurcation characteristics quadratic feedback control

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A machine learning approach to quality-control Argo temperature data

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Atmospheric and Oceanic science Letters 2023年第4期16卷 1-7页

作者： Qi Zhang Chenyan Qian Changming Dong School of Marine Sciences Nanjing University of Information Science and TechnologyNanjingChina Longshan College Nanjing University of Information Science and TechnologyNanjingChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina

本文提出了一种基于机器学习的Argo浮标温度异常值检测方法.该方法采用机器学习无监督算法高斯混合模型对Argo浮标数据进行聚类分析,并构建包围所有数据点的最小多边形的凸包.基于射线投影算法实现点在多边形内分析,通过自动识别数据点... 详细信息

本文提出了一种基于机器学习的Argo浮标温度异常值检测方法.该方法采用机器学习无监督算法高斯混合模型对Argo浮标数据进行聚类分析,并构建包围所有数据点的最小多边形的凸包.基于射线投影算法实现点在多边形内分析,通过自动识别数据点位于凸包内外来判断该数据点数据质量的好坏.本文采用南海区域Argo浮标数据对该方法进行测试,结果表明该方法可以识别70%以上的包含异常值的温度剖面,同时自动标记出各异常值点.

关键词：质量控制机器学习异常值检测高斯混合模型凸包点在多边形内

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The interplay between histone modifications and nuclear lamina in genome regulation

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Journal of Genetics and Genomics 2025年第1期52卷 24-38页

作者： Chang Sun Yanjing Zhao Liping Guo Juhui Qiu Qin Peng Institute of Systems and Physical Biology Shenzhen Bay LaboratoryShenzhen 518132China Faculty of Medicine and Health Sciences Barcelona UniversityBarcelonaSpain Division of Life Science Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina School of Biology and Biological Engineering South China University of TechnologyGuangzhouGuangdong 510006China Key Laboratory for Biorheological Science and Technology of Ministry of Education State and Local Joint Engineering Laboratory for Vascular ImplantsCollege of BioengineeringChongqing UniversityChongqing 400030China

Gene expression is regulated by chromatin architecture and epigenetic remodeling in cell homeostasis and *** modifications act as the key factors to modulate the chromatin *** histone modifications are strongly associated with the localization of *** primarily localizes at the nuclear periphery,where it interacts with lamina proteins to suppress gene *** this review,we summarize the potential bridges that have regulatory functions of histone modifications in chromatin organization and transcriptional regulation at the nuclear *** use lamina-associated domains(LADs)as examples to elucidate the biological roles of the interactions between histone modifications and nuclear lamina in cell differentiation and *** the end,we highlight the technologies that are currently used to identify and visualize histone modifications and LADs,which could provide spatiotemporal information for understanding their regulatory functions in gene expression and discovering new targets for diseases.

关键词： Histone modifications Chromatin organization Nuclear lamina Lamina-associated domain Genome regulation Cell differentiation

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Privacy-Preserving Pseudonym Schemes for Personalized 3D Avatars in Mobile Social Metaverses 6

Privacy-Preserving Pseudonym Schemes for Personalized 3D Ava...

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6th International Conference on Electronics and Communication, Network and Computer technology, ECNCT 2024

作者： Su, Cheng Luo, Xiaofeng Liu, Zhenmou Kang, Jiawen Hao, Min Xiong, Zehui Yang, Zhaohui Huang, Chongwen School of Automation Guangdong University of Technology Guangzhou China School of Systems Science and Engineering Sun Yat-sen University Guangzhou510275 China Singapore University of Technology and Design Information Systems Technology and Design Pillar Singapore College of Information Science and Electronic Engineering Zhejiang University Hangzhou China

ISBN: (纸本)9798350366143

The emergence of mobile social metaverses, a novel paradigm bridging physical and virtual realms, has led to the widespread adoption of avatars as digital representations for Social Metaverse Users (SMUs) within virtual spaces. Equipped with immersive devices, SMUs leverage Edge Servers (ESs) to deploy their avatars and engage with other SMUs in virtual spaces. To enhance immersion, SMUs incline to opt for 3D avatars for social interactions. However, existing 3D avatars are typically generated through scanning the real faces of SMUs, which can raise concerns regarding information privacy and security, such as profile identity leakages. To tackle this, we introduce a new framework for personalized 3D avatar construction, leveraging a two-layer network model that provides SMUs with the option to customize their personal avatars for privacy preservation. Specifically, our approach introduces avatar pseudonyms to jointly safeguard the profile and digital identity privacy of the generated avatars. Then, we design a novel metric named Privacy of Personalized Avatars (PoPA), to evaluate effectiveness of the avatar pseudonyms. To optimize pseudonym resource, we model the pseudonym distribution process as a Stackelberg game and employ Deep Reinforcement Learning (DRL) to learn equilibrium strategies under incomplete information. Simulation results validate the efficacy and feasibility of our proposed schemes for mobile social metaverses. © 2024 IEEE.

关键词： Differential privacy

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Numerical and experimental studies on the effectiveness of time-varying electromagnetic fields in reducing electron density

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Plasma science and technology 2023年第6期25卷 30-40页

作者：郭韶帅谢楷徐晗付麦霞牛营营 Key Laboratory of Grain Information Processing and Control(Henan University of Technology) Ministry of EducationZhengzhou 450001People's Republic of China College of Information Science and Engineering Henan University of TechnologyZhengzhou 450001People's Republic of China School of Aerospace Science and Technology Xidian UniversityXi'an 710071People's Republic of China

When an aircraft or a hypersonic vehicle re-enters the atmosphere,the plasma sheath generated can severely attenuate electromagnetic wave signals,causing the problem of communication blackout.A new method based on time-varying E×B fields is proposed to improve on the existing static E×B fields and mitigate the radio blackout *** use of the existing method is limited by the invalid electron density reduction resulting from current density j=0 A m^(-2)in plasma beyond the Debye *** most remarkable feature is the introduction of a time-varying electric field to increase the current density in the plasma to overcome the Debye shielding effect on static electric ***,a magnetic field with the same frequency and phase as the electric field is applied to ensure that the electromagnetic force is always acting on the plasma in one *** order to investigate the effect of time-varying E×B fields on the plasma electron density distribution,two directions of voltage application are considered in numerical *** simulation results indicate that different voltage application methods generate electromagnetic forces in different directions in the plasma,resulting in repulsion and vortex effects in the plasma.A comparison of the vortex effect and repulsion effect reveals that the vortex effect is better at reducing the electron *** local plasma electron density can be reduced by more than 80%through the vortex effect,and the dimensions of the area of reduced electron density reach approximately 6 cm×4 cm,meeting the requirements of electromagnetic wave ***,the vortex effect of reducing the electron density in RAM-C(radio attenuation measurements for the study of communication blackout)reentry at an altitude of 40 km is *** the basis of the simulation results,an experiment based on a rectangular-window discharge device is proposed to demonstrate the effectiveness of the vortex *** results show t

关键词： blackout magnetic window method time-varying E×B fields

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A Q-Learning Based Hybrid Meta-Heuristic for Integrated Scheduling of Disassembly and Reprocessing Processes Considering Product Structures and Stochasticity

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Complex System Modeling and Simulation 2024年第2期4卷 184-209页

作者： Fuquan Wang Yaping Fu Kaizhou Gao Yaoxin Wu Song Gao the School of Business Qingdao UniversityQingdao 266071China the Macao Institute of Systems Engineering Macao University of Science and TechnologyMacao 999078China the Department of Industrial Engineering&Innovation Sciences Eindhoven University of TechnologyEindhoven5600 MBthe Netherlands the College of Information Science and Engineering Northeastern UniversityShenyang 110819China

Remanufacturing is regarded as a sustainable manufacturing paradigm of energy conservation and environment *** improve the efficiency of the remanufacturing process,this work investigates an integrated scheduling problem for disassembly and reprocessing in a remanufacturing process,where product structures and uncertainty are taken into ***,a stochastic programming model is developed to minimize the maximum completion time(makespan).Second,a Q-learning based hybrid meta-heuristic(Q-HMH)is specially *** each iteration,a Q-learning method is employed to adaptively choose a premium algorithm from four candidate ones,including genetic algorithm(GA),artificial bee colony(ABC),shuffled frog-leaping algorithm(SFLA),and simulated annealing(SA)*** last,simulation experiments are carried out by using sixteen instances with different scales,and three state-of-the-art algorithms in literature and an exact solver CPLEX are chosen for *** analyzing the results with the average relative percentage deviation(RPD)metric,we find that Q-HMH outperforms its rivals by 9.79%-26.76%.The results and comparisons verify the excellent competitiveness of Q-HMH for solving the concerned problems.

关键词： remanufacturing scheduling disassembly reprocessing meta-heuristic Q-learning

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Resource Allocation for Underwater Acoustic Sensor Networks With Partial Spectrum Sharing: When Optimization Meets Deep Reinforcement Learning

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IEEE Transactions on Network and Service Management 2025年第3期22卷 2715-2730页

作者： Tang, Rui Zhang, Ruizhi Xu, Yongjun Liu, Chuan Huang, Chongwen Yuen, Chau China West Normal University School of Electronic Information Engineering Key Laboratory of Optimization Theory and Applications Internet of Things Perception and Big Data Analysis Key Laboratory of Nanchong City Sichuan Nanchong637002 China University of Electronic Science and Technology of China School of Information and Communication Engineering Chengdu611731 China Chongqing University of Posts and Telecommunications School of Communications and Information Engineering Chongqing400064 China Zhejiang University College of Information Science and Electronic Engineering Hangzhou310027 China Nanyang Technological University School of Electrical and Electronics Engineering Jurong West 639798 Singapore

To utilize the limited acoustic spectrum while combating the harsh underwater propagation, we incorporate partial spectrum sharing into an underwater acoustic sensor network and aim to maximize the minimum data collection rate among all underwater sensor nodes through joint power allocation and spectrum assignment. To cope with the non-convex optimization problem, we propose a Hybrid Model-based and Data-based Resource Allocation (HMDRA) scheme: 1) Under any given spectrum assignment strategy, we analyze the impact of the partial spectrum sharing and imperfect successive interference cancellation on baseband signal processing, and formulate a power allocation problem that is solved by the bisection method and Lagrange dual theory. 2) Based on the optimal power allocation strategy, the gradient-free genetic algorithm (GA) is first adopted to approach the optimal solution of the model-less spectrum assignment problem by nearly enumerating the solution space. To reduce complexity, we further propose a deep reinforcement learning (DRL)-based algorithm and obtain an efficient solution by traversing a deep neural network-based policy learned from the training stage. Simulation results show that compared with the GA-based algorithm, the average execution time of the DRL-based algorithm is substantially reduced by 5 orders of magnitude to 0.7076 seconds at the cost of approximately 6 percent performance loss. © 2004-2012 IEEE.

关键词： Deep reinforcement learning

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An in-situ biochar-enhanced anaerobic membrane bioreactor for swine wastewater treatment under various organic loading rates

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Journal of Environmental sciences 2024年第12期146卷 304-317页

作者： Nianwen Chen Xinbo Zhang Qing Du Huizhong Wang Zhiwen Wang Junzhi Ren Hongxia Li Wenshan Guo Huu Hao Ngo Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess School of Environmental and Municipal EngineeringTianjin Chengjian UniversityTianjin 300384China Tianjin Key Laboratory of Aquatic Science and Technology Tianjin Chengjian UniversityTianjin 300384China Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) SynBio Research PlatformCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Department of Biochemical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Tianjin Caring Technology Development Co. Ltd.Tianjin 300381China Centre for Technology in Water and Wastewater School of Civil and Environmental EngineeringUniversity of Technology SydneySydneyNSW 2007Australia

A biochar-assisted anaerobic membrane bioreactor(BC-AnMBR)was conducted to evaluate the performance in treating swine wastewater with different organic loading rates(OLR)ranging from 0.38 to 1.13 kg-COD/(m3.d).Results indicated that adding spent coffee grounds biochar(SCG-BC)improved the organic removal efficiency compared to the conventional AnMBR,with an overall COD removal rate of>95.01%.Meanwhile,methane production of up to 0.22 LCH4/gCOD with an improvement of 45.45%was achieved under a high OLR of 1.13 kg-COD/(m3.d).Furthermore,the transmembrane pressure(TMP)in the BC-AnMBR system was stable at 4.5 kPa,and no irreversible membrane fouling occurred within 125 *** community analysis revealed that the addition of SCG-BC increased the relative abundance of autotrophic methanogenic archaea,particularly Methanosarcina(from 0.11%to 11.16%)and Methanothrix(from 16.34%to 24.05%).More importantly,Desulfobacterota and Firmicutes phylum with direct interspecific electron transfer(DIET)capabilities were also enriched with autotrophic *** of the electron transfer pathway showed that the concentration of c-type cytochromes increased by 38.60%in the presence of SCGBC,and thus facilitated the establishment of DIET and maintained high activity of the elec-tron transfer system even at high *** short,the BC-AnMBR system performs well under various OLR conditions and is stable in the recovery energy system for swine wastewater.

关键词： Biochar Microbial community Anaerobic membrane bioreactor Organic loading rates Methane production

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