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Evolution of STBC-Based OFDM-IM for Wireless Vehicular Communication
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作者 Tanairat Mata Pisit Boonsrimuang 《China Communications》 2026年第2期51-68,共18页
This paper studies wireless vehicular communication(VehCom)in intelligent transportation systems using an orthogonal frequency division multiplexing with index modulation(OFDM-IM).In the concept of IM,data is transmit... This paper studies wireless vehicular communication(VehCom)in intelligent transportation systems using an orthogonal frequency division multiplexing with index modulation(OFDM-IM).In the concept of IM,data is transmitted not only through the modulated symbols but also via the indices of the active subcarriers.In contrast to the original OFDM,OFDM-IM activates only non-zero subcarriers,increasing energy efficiency.However,the pilotassisted channel estimation(CE)method is a significant challenge in OFDM-IM,where the desired pilot subcarrier interval is related to the OFDM-IM subblock length.This paper proposes a walsh-scattered pilot-assisted CE for OFDM-IM VehCom.The optimum walsh-scattered pilot assignment is proposed to improve the transmission efficiency.Furthermore,a space-time block code with a high transmit diversity gain is employed for OFDM-IM VehCom to enhance VehCom's signal quality.The results show that the proposed method performs higher CE accuracy and better bit-error rate with significant spectral and energy efficiencies than conventional methods. 展开更多
关键词 index modulation intelligent transportation systems pilot-assisted channel estimation space-time block code wireless vehicular communication
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Efficient Polar Codes with Low Complexity for Correcting Insertions/Deletions in DPPM
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作者 Li Leran Liu Yuan +2 位作者 Yuan Ye Xiahou Wenqian Chen Maonan 《China Communications》 2026年第1期24-33,共10页
Differential pulse-position modulation(DP PM)can achieve a good compromise between power and bandwidth requirements.However,the output sequence has undetectable insertions and deletions.This paper proposes a successiv... Differential pulse-position modulation(DP PM)can achieve a good compromise between power and bandwidth requirements.However,the output sequence has undetectable insertions and deletions.This paper proposes a successive cancellation(SC)decoding scheme based on the weighted levenshtein distance(WLD)of polar codes for correcting insertions/deletions in DPPM systems.In this method,the WLD is used to calculate the transfer probabilities recursively to obtain likelihood ratios,and the low-complexity SC decoding method is built according to the error characteristics to match the DPPM system.Additionally,the proposed SC decoding scheme is extended to list decoding,which can further improve error correction performance.Simulation results show that the proposed scheme can effectively correct insertions/deletions in the DPPM system,which enhances its reliability and performance. 展开更多
关键词 DPPM insertions/deletions polar codes SC decoding
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Room temperature gas sensor based on porous NiO nanoplates modified with rGO nanosheets and SnO_(2)nanoparticles for accurate and rapid ppb-level NO_(2)detection
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作者 Haineng Bai Cheng Feng +10 位作者 Yiru Chen Yunxiao Du Yamin Feng Kuili Liu Yali Yan Jia Liu Baohua Zhang Jin Wang Dunjun Chen Youdou Zheng Fuqiang Guo 《Nano Materials Science》 2026年第1期36-48,共13页
The porous NiO nanoplates modified with rGO nanosheets and SnO_(2)nanoparticles are developed for accurate and rapid ppb-level NO_(2)detection.The developed SnO_(2)/NiO/rGO sensor towards 50 ppm NO_(2)gas demonstrates... The porous NiO nanoplates modified with rGO nanosheets and SnO_(2)nanoparticles are developed for accurate and rapid ppb-level NO_(2)detection.The developed SnO_(2)/NiO/rGO sensor towards 50 ppm NO_(2)gas demonstrates an excellent gas-sensing response of 14.8 at 23℃,which is 3.03 times that of Ni O/rGO sensor(4.89)and 6.49 times that of NiO sensor(2.28),respectively.The developed SnO_(2)/NiO/rGO sensor exhibits faster response/recovery speed(12.7/32.8 s@5 ppm),with extra-low theoretical detection limit of 0.15 ppb at room temperature.More fascinatingly,our sensors indicate great sensitivity,outstanding repeatability and long-term stability for longer than 7 weeks.Additionally,it also suggests that 1℃and 1%relative humidity have the same effect on the SnO_(2)/NiO/rGO sensor signal as approximately 13 ppb and 7.0 ppb NO_(2)gas change,respectively.Such excellent properties are mainly attributed to the large surface-to-volume ratio,which provides active sites to NO_(2)gas spread,adsorption and diffusion on material surface in redox reaction.Moreover,the ternary heterojunctions formed by NiO,rGO and SnO_(2)may serve as highly conductive channels to accelerate carrier transfer and abundant oxygen vacancies to reduce the adsorption energy for O_(2)and NO_(2)gas,thus further improving performance of the sensors. 展开更多
关键词 NO_(2)sensor SnO_(2)/NiO/rGO heterostructure Room temperature Ultralow detection limit Sensing mechanism
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A versatile strategy to activate self-sacrificial templated Li_(2)MnO_(3) by defect engineering toward advanced lithium storage 被引量:1
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作者 Jian-En Zhou Yanhua Peng +7 位作者 Xiaoyan Sang Chunlei Wu Yiqing Liu Zhijian Peng Hong Ou Yongbo Wu Xiaoming Lin Yuepeng Cai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期164-180,I0007,共18页
Despite the dazzling theoretical capacity,the devasting electrochemical activity of Li_(2)MnO_(3)(LMO)caused by the difficult oxidation of Mn4+impedes its practical application as the lithium-ion battery(LIB)cathode.T... Despite the dazzling theoretical capacity,the devasting electrochemical activity of Li_(2)MnO_(3)(LMO)caused by the difficult oxidation of Mn4+impedes its practical application as the lithium-ion battery(LIB)cathode.The efficacious activation of the Li_(2)MnO_(3) by importing electrochemically active Mn3+ions or morphological engineering is instrumental to its lithium storage activity and structural integrity upon cycling.Herein,we propose a conceptual strategy with metal-organic frameworks(MOFs)as self-sacrificial templates to prepare oxygen-deficient Li_(2)MnO_(3)(O_v-LMO)for exalted lithium storage performance.Attributed to optimized morphological features,LMO materials derived from Mn-BDC(H_(2)BDC=1,4-dicarboxybenzene)delivered superior cycling/rate performances compared with their counterparts derived from Mn-BTC(H_(3)BTC=1,3,5-benzenetricarboxylicacid)and Mn-PTC(H_(4)PTC=pyromellitic acid).Both experimental and theoretical studies elucidate the efficacious activation of primitive LMO materials toward advanced lithium storage by importing oxygen deficiencies.Impressively,O_v-LMO derived from Mn-BDC(O_v-BDC-LMO)delivered intriguing reversible capacities(179.2 mA h g^(-1)at 20 mA g^(-1)after 200 cycles and 100.1 mA h g^(-1)at 80 mA g^(-1)after 300 cycles),which can be attributed to the small particle size that shortens pathways for Li+/electron transport,the enhanced redox activity induced by abundant oxygen vacancies,and the optimized electronic configuration that contributes to the faster lithium diffusivity.This work provides insights into the rational design of LMO by morphological and atomic modulation to direct its activation and practical application as an advanced LIB cathode. 展开更多
关键词 Li_(2)MnO_(3) Metal-organic framework Oxygen vacancy Lithium-ion battery Electrochemical activity
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Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption 被引量:4
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作者 Jiaolong Liu Siyu Zhang +14 位作者 Dan Qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou Kai Tao Mengyang Li Bing Wei Hongjing Wu Mengyang Li Bing Wei Hongjing Wu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期528-547,共20页
Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic dissipation.Conventional methods,how... Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic dissipation.Conventional methods,however,constrain their delicate constructions.Herein,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon matrix.This unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial polarization.Such“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first time.Consequently,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric response.Harnessing defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response. 展开更多
关键词 Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption
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Enhanced battery life prediction with reduced data demand via semi-supervised representation learning 被引量:2
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作者 Liang Ma Jinpeng Tian +2 位作者 Tieling Zhang Qinghua Guo Chi Yung Chung 《Journal of Energy Chemistry》 2025年第2期524-534,I0011,共12页
Accurate prediction of the remaining useful life(RUL)is crucial for the design and management of lithium-ion batteries.Although various machine learning models offer promising predictions,one critical but often overlo... Accurate prediction of the remaining useful life(RUL)is crucial for the design and management of lithium-ion batteries.Although various machine learning models offer promising predictions,one critical but often overlooked challenge is their demand for considerable run-to-failure data for training.Collection of such training data leads to prohibitive testing efforts as the run-to-failure tests can last for years.Here,we propose a semi-supervised representation learning method to enhance prediction accuracy by learning from data without RUL labels.Our approach builds on a sophisticated deep neural network that comprises an encoder and three decoder heads to extract time-dependent representation features from short-term battery operating data regardless of the existence of RUL labels.The approach is validated using three datasets collected from 34 batteries operating under various conditions,encompassing over 19,900 charge and discharge cycles.Our method achieves a root mean squared error(RMSE)within 25 cycles,even when only 1/50 of the training dataset is labelled,representing a reduction of 48%compared to the conventional approach.We also demonstrate the method's robustness with varying numbers of labelled data and different weights assigned to the three decoder heads.The projection of extracted features in low space reveals that our method effectively learns degradation features from unlabelled data.Our approach highlights the promise of utilising semi-supervised learning to reduce the data demand for reliability monitoring of energy devices. 展开更多
关键词 Lithium-ion batteries Battery degradation Remaining useful life Semi-supervised learning
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Recent Advances in Sustainable Concrete and Steel Alternatives for Marine Infrastructure 被引量:2
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作者 Kiran Napte Ganesh E.Kondhalkar +4 位作者 Shilpa Vishal Patil Pallavi Vishnu Kharat Snehal Mayur Banarase Anant Sidhappa Kurhade Shital Yashwant Waware 《Sustainable Marine Structures》 2025年第2期107-131,共25页
Marine infrastructure is increasingly vulnerable to harsh environmental conditions that accelerate the degradation of traditional materials such as Portland cement concrete and carbon steel.This review systematically ... Marine infrastructure is increasingly vulnerable to harsh environmental conditions that accelerate the degradation of traditional materials such as Portland cement concrete and carbon steel.This review systematically investigates recent advancements in sustainable alternatives,including geopolymer concrete,engineered innovacementitious composites(ECC),bio-concrete,fiber-reinforced polymers(FRPs),and bamboo,stainless steel,and steel-CFRP hybrid bars.Each material is evaluated based on marine durability,mechanical performance,environmental impact,and cost feasibility using life cycle assessment,durability modelling,and a multi-criteria decisionsupport framework.The results reveal that geopolymer concrete and FRP reinforcement’s exhibit superior corrosion resistance and environmental benefits,while ECC and steel-CFRP composites offer structural resilience with moderate environmental trade-offs.However,challenges remain in long-term performance validation,standardization,and market integration.The review concludes that a combined approach involving innovative materials,computational tools,and sustainability assessment is essential for advancing marine infrastructure.Outlook recommendations include focused field studies,development of regulatory guidelines,and interdisciplinary collaboration to drive the practical adoption of eco-efficient materials in coastal and offshore construction. 展开更多
关键词 Bio-Concrete Self-Healing Materials Corrosion-Resistant Reinforcement Fiber-Reinforced Polymer(FRP)Composites Geopolymer Concrete Life Cycle Assessment in Construction Sustainable Marine Infrastructure
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Fluorescent Copper Nanoclusters:From Synthesis to Environmental Pollutants Sensing
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作者 Lingwei Hu Xiangqian Li +3 位作者 Zhuohan Zhou Rumeng Zhao Lingling Sun Jitao Li 《化学进展》 北大核心 2025年第12期1792-1819,共28页
Copper nanoclusters(CuNCs)have gained prominence due to their remarkable color-tunable light emission and cost-effective,versatile solution-based synthesis.The use of various functional ligands in the synthesis of CuN... Copper nanoclusters(CuNCs)have gained prominence due to their remarkable color-tunable light emission and cost-effective,versatile solution-based synthesis.The use of various functional ligands in the synthesis of CuNCs enables the modulation of their emission wavelengths and enhances their environmental stability.These nanoclusters have found applications across diverse fields,including catalysis,sensing,bioimaging,and optoelectronics.This review offers a focused and up-to-date perspective by covering literature from the past decade(2015―2025)with an explicit emphasis on practical environmental matrices,including heavy metal ions,organic pollutants,pharmaceuticals,and other environmental contaminants.It systematically compares sensing mechanisms(e.g.,fluorescence quenching,turn-on responses,ratiometric and inner-filter effects)and provides tabulated limits of detection for key heavy metals,organic pollutants,and pharmaceuticals to facilitate direct benchmarking.Finally,the review highlights translational gaps for in-field deployment,such as matrix interferences,long-term stability of ligand-stabilized CuNCs,sample pre-treatment needs,and the absence of standardized validation protocols and proposes targeted research directions to bridge laboratory advances with real-world environmental monitoring. 展开更多
关键词 copper nanoclusters synthetic approaches ligand design environmental pollutant
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Magnitude and uniformity improvement of the received optical power for an indoor VLC system jointly assisted by angle-diversity transceivers and STAR-IRS
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作者 YANG Ting WANG Ping +3 位作者 HE Huimeng XIONG Yingfei SUN Yanzhe LIU Qi 《Optoelectronics Letters》 2025年第11期671-676,共6页
To improve the quality of the illumination distribution,one novel indoor visible light communication(VLC)system,which is jointly assisted by the angle-diversity transceivers and simultaneous transmission and reflectio... To improve the quality of the illumination distribution,one novel indoor visible light communication(VLC)system,which is jointly assisted by the angle-diversity transceivers and simultaneous transmission and reflection-intelligent reflecting surface(STAR-IRS),has been proposed in this work.A Harris Hawks optimizer algorithm(HHOA)-based two-stage alternating iteration algorithm(TSAIA)is presented to jointly optimize the magnitude and uniformity of the received optical power.Besides,to demonstrate the superiority of the proposed strategy,several benchmark schemes are simulated and compared.Results showed that compared to other optimization strategies,the TSAIA scheme is more capable of balancing the average value and variance of the received optical power,when the maximal ratio combining(MRC)strategy is adopted at the receiver.Moreover,as the number of the STAR-IRS elements increases,the optical power variance of the system optimized by TSAIA scheme would become smaller while the average optical power would get larger.This study will benefit the design of received optical power distribution for indoor VLC systems. 展开更多
关键词 indoor VLC Two Stage Alternating Iteration Algorithm Harris Hawks Optimizer optimize magnitude uniformity star IRS demonstrate superiori improve quality illumination distributionone angle diversity transceivers
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An NOMA-VLC power allocation scheme for multi-user based on sparrow search algorithm
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作者 WANG Xing WANG Haitao +3 位作者 DONG Zhenliang XIONG Yingfei SHI Huili WANG Ping 《Optoelectronics Letters》 2025年第5期278-283,共6页
A non-orthogonal multiple access(NOMA) power allocation scheme on the basis of the sparrow search algorithm(SSA) is proposed in this work. Specifically, the logarithmic utility function is utilized to address the pote... A non-orthogonal multiple access(NOMA) power allocation scheme on the basis of the sparrow search algorithm(SSA) is proposed in this work. Specifically, the logarithmic utility function is utilized to address the potential fairness issue that may arise from the maximum sum-rate based objective function and the optical power constraints are set considering the non-negativity of the transmit signal, the requirement of the human eyes safety and all users' quality of service(Qo S). Then, the SSA is utilized to solve this optimization problem. Moreover, to demonstrate the superiority of the proposed strategy, it is compared with the fixed power allocation(FPA) and the gain ratio power allocation(GRPA) schemes. Results show that regardless of the number of users considered, the sum-rate achieved by SSA consistently outperforms that of FPA and GRPA schemes. Specifically, compared to FPA and GRPA schemes, the sum-rate obtained by SSA is increased by 40.45% and 53.44% when the number of users is 7, respectively. The proposed SSA also has better performance in terms of user fairness. This work will benefit the design and development of the NOMA-visible light communication(VLC) systems. 展开更多
关键词 NOMA logarithmic utility function VLC Sparrow Search Algorithm sparrow search algorithm ssa fairness issue power allocation Sum Rate
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Long term wind energy forecasting using machine learning techniques
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作者 Marcos V.M.Siqueira Vitor H.Ferreira Angelo C.Colombini 《Global Energy Interconnection》 2025年第6期1030-1046,共17页
Ensuring the reliability of wind energy as a dependable source requires overcoming challenges posed by the inherent volatility and stochastic nature of wind patterns.Long-term forecasting provides strategic advantages... Ensuring the reliability of wind energy as a dependable source requires overcoming challenges posed by the inherent volatility and stochastic nature of wind patterns.Long-term forecasting provides strategic advantages in managing energy generation projects,enabling the development of effective portfolio management strategies.The primary objective of this study was the development of forecasting methods to support strategic decision-making within the scope of wind energy operations,specifically targeting the PindaíWind Complex and its commercial dispatch.The study integrated Big Data analytics,data engineering,and computational techniques through the application of machine learning algorithms:including eXtreme Gradient Boosting,Multilayer Perceptron,Support Vector Regression,Ridge Regression,and Random Forests,aiming to generate forward-looking projections of the complex’s energy production for the year 2023.To this end,five supervised machine learning techniques were modeled and implemented.These techniques were grounded in their respective mathematical and structural formulations,and the empirical foundation for modeling was provided by historical power generation data from the PindaíWind Complex,combined with high-resolution realized and forecasted meteorological data retrieved via the Open-Meteo API.The models are trained using historical monthly generation data from the PindaíWind Complex,which has an installed capacity of 79.9 MW and is located in the northeastern region of Brazil,along with meteorological data from reanalysis models,such as air temperature,relative humidity,precipitation,surface pressure,wind speed at 10 m,wind speed at 100 m,and wind gusts.These methodologies are applied to forecast monthly wind generation for the year 2023,and the outputs are systematically compared using evaluation metrics to determine the most suitable modeling approach.The results highlight the superiority of the Multilayer Perceptron,Support Vector Regression,and eXtreme Gradient Boosting models,which achieved Kling-Gupta Efficiency(KGE)of 0.89,0.89,and 0.90,mean absolute scaled error(MASE)of 0.29,0.31,and 0.18,root mean square errors(RMSE)of 0.56,0.59,and 0.35,and mean absolute errors(MAE)of 0.48,0.52,and 0.29,respectively. 展开更多
关键词 Eextreme gradient boosting Machine learning Multilayer perceptron Pindaíwind complex Random forests Ridge linear regression Support vector machines
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Motor Imagery(MI)-Electroencephalogram(EEG)Decoding Method Based on Multi-modal Temporal Fusion and Spatial Asymmetry
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作者 Zhikang YIN Chunjiang SHUAI 《Agricultural Biotechnology》 2025年第6期88-95,99,共9页
Deep learning methods have been widely applied in motor imagery(MI)-based brain-computer interfaces(BCI)for decoding electroencephalogram(EEG)signals.High temporal resolution and asymmetric spatial activation are fund... Deep learning methods have been widely applied in motor imagery(MI)-based brain-computer interfaces(BCI)for decoding electroencephalogram(EEG)signals.High temporal resolution and asymmetric spatial activation are fundamental properties of EEG during MI processes.However,due to the limited receptive field of convolutional kernels,traditional convolutional neural networks(CNNs)often focus only on local features,and are insufficient to cover neural processes across different frequency bands and duration scales.This limitation hinders the effective characterization of rhythmic activity changes in MI-EEG signals over time.Additionally,MI-EEG signals exhibit significant asymmetric activation between the left and right hemispheres.Traditional spatial feature extraction methods overlook the interaction between global and local regions at the spatial scale of EEG signals,resulting in inadequate spatial representation and ultimately limiting decoding accuracy.To address these limitations,in this study,a novel deep learning network that integrates multi-modal temporal features with spatially asymmetric feature modeling was proposed.The network first extracts multi-modal temporal information from EEG data channels,and then captures global and hemispheric spatial features in the spatial dimension and fuses them through an advanced fusion layer.Global dependencies are captured using a self-attention module,and a multi-scale convolutional fusion module is introduced to explore the relationships between the two types of temporal features.The fused features are classified through a classification layer to accomplish motor imagery task classification.To mitigate the issue of limited sample size,a data augmentation strategy based on signal segmentation and recombination is designed.Experimental results on the BCI Competition IV-2a(bbic-IV-2a)and BCI Competition IV-2b(bbic-IV-2a)datasets demonstrated that the proposed method achieved superior accuracy in multi-class motor imagery classification compared with existing models.On the BCI-IV-2a dataset,it attained an average classification accuracy of 84.36%,while also showing strong performance on the binary classification BCI-IV-2b dataset.These outcomes validate the capability of the proposed network to enhance MI-EEG classification accuracy. 展开更多
关键词 Deep learning Brain-computer interface(BCI) Convolutional neural network(CNN) Electroencephalogram(EEG) Motor imagery(MI)
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The ρ-Meson Electromagnetic Form Factors within the Light-Front Quark Model
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作者 Shuai Xu Xiao-Nan Li Xing-Gang Wu 《Chinese Physics Letters》 2025年第8期31-37,共7页
In this paper,we study the ρ-meson electromagnetic form factors(EMFFs)within the framework of the light-front quark model.The physical form factors G_(C,M,Q)(Q^(2))of the ρ-meson,as well as the charged square radius... In this paper,we study the ρ-meson electromagnetic form factors(EMFFs)within the framework of the light-front quark model.The physical form factors G_(C,M,Q)(Q^(2))of the ρ-meson,as well as the charged square radius<r^(2)>,the magnetic moment μ,and the quadrupole moment Q,are calculated,which describe the behaviors of EMFFs at zero momentum transfer.Using the type-Ⅱ replacement,we find that the zero-mode does contribute zero to the matrix element S_(00)^(+).It is found that the“M→M_(0)”replacement improves the angular condition remarkably,which permits different prescriptions of ρ-meson EMFFs to give the consistent results.The residual tiny violation of angular condition needs other explanations beyond the zero-mode contributions.Our results indicate that the relativistic effects or interaction internal structure are weaken in the zero-binding limit.This work is also applicable to other spin-1 particles. 展开更多
关键词 light front quark model zero mode contribution electromagnetic form factors emffs within relativistic effects rho meson magnetic moment electromagnetic form factors angular condition
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Multi-agent SAC approach aided joint trajectory and power optimization for multi-UAV assisted wireless networks with safety constraints
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作者 Jia SHI Zan LI +3 位作者 Wentao SUN Zixuan BAI Feng WANG Tony Q.S.QUEK 《Chinese Journal of Aeronautics》 2025年第10期19-31,共13页
Unmanned Aerial Vehicles(UAVs)have demonstrated significant potential as Aerial Base Stations(A-BSs)for providing data services to Ground Users(GUs),attributed to their flexibility,cost-effectiveness,and high likeliho... Unmanned Aerial Vehicles(UAVs)have demonstrated significant potential as Aerial Base Stations(A-BSs)for providing data services to Ground Users(GUs),attributed to their flexibility,cost-effectiveness,and high likelihood of establishing line-of-sight links.In this article,we formulate the joint power and trajectory optimization problem for a multi-UAV assisted wireless network with no-fly zones constrained,aiming at maximizing the Accumulated Service Data(ASD)of UAVs and minimizing the Average End Age of Information(AEAoI)of GUs.Specifically,this paper proposes the Multi-Agent worst-case Soft Actor Critic(MA-wcSAC)algorithm with a distributional safety-critic.The simulation results demonstrate that,compared to the Multi-Agent Soft Actor Critic(MA-SAC)algorithm,the proposed algorithm exhibits comparable data service performance while reducing security risks by at least 30%at different risk levels. 展开更多
关键词 Unmanned Aerial Vehicle(UAV) Age of Information(AoI) Safety constraint Trajectory design Power allocation Multi-agent worst-case soft actor critic(MA-wcSAC)
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Location-driven beamforming for massive multi-user MIMO systems
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作者 MA Tao HUANG Jun +1 位作者 ZU Jiahao LI Wen’gang 《Journal of Systems Engineering and Electronics》 2025年第3期609-622,共14页
Using the existing positioning technology can easily obtain high-precision positioning information,which can save resources and reduce complexity when used in the communication field.In this paper,we propose a locatio... Using the existing positioning technology can easily obtain high-precision positioning information,which can save resources and reduce complexity when used in the communication field.In this paper,we propose a location-based user scheduling and beamforming scheme for the downlink of a massive multi-user input-output system.Specifically,we combine an analog outer beamformer with a digital inner beamformer.An outer beamformer can be selected from a codebook formed by antenna steering vectors,and then a reduced-complexity inner beamformer based on iterative orthogonal matrices and right triangular matrices(QR)decomposition is applied to cancel interuser interference.Then,we propose a low-complexity user selection algorithm using location information in this paper.We first derive the geometric angle between channel matrices,which represent the correlation between users.Furthermore,we derive the asymptotic signal to interference-plus-noise ratio(SINR)of the system in the context of two-stage beamforming using random matrix theory(RMT),taking into account inter-channel correlations and energies.Simulation results show that the algorithm can achieve higher system and speed while reducing computational complexity. 展开更多
关键词 massive multiple input multiple output user scheduling two-stage beamforming LOW-COMPLEXITY
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Multi-model Switching Control Study of a Full-Car Suspension System for Balancing Ride Comfort and Handling Stability
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作者 Fubao Xu Xiangjun Xia +3 位作者 Jing Cao Pengfei Liu Donghong Ning Haiping Du 《Chinese Journal of Mechanical Engineering》 2025年第5期83-100,共18页
The cooperative control of ride comfort and handling stability in automobile suspension systems presents a significant challenge in intelligent chassis system design.This complexity arises from the high degrees of fre... The cooperative control of ride comfort and handling stability in automobile suspension systems presents a significant challenge in intelligent chassis system design.This complexity arises from the high degrees of freedom,diverse operating conditions,and inherent trade-offs between performance metrics in full-car suspension systems.In this paper,a novel switching control strategy is proposed to better balance ride comfort and handling stability for a full-car suspension system.The system integrates a ride comfort controller and an anti-rollover controller,guided by a new rollover risk assessment indicator that requires fewer state variables.First,a vehicle suspension simplification model approach is introduced,reducing the fourteen-degree-of-freedom full-car suspension model to three two-degree-of-freedom models:vertical,pitch and roll.Based on these simplified models,vertical,roll,and pitch controllers are designed,simplifying the controller design process for full-car suspension systems.The ride comfort controller is constructed using the modal energy method in conjunction with the simplified model controllers,while the roll controller functions as the anti-rollover controller.The proposed rollover risk assessment indicator serves as the switching criterion between handling stability and ride comfort control.Experimental results demonstrate that the proposed switching control strategy effectively adapts to various road conditions,enabling the semi-active variable damping suspension system to perform multi-modal switching.Compared to a well-tuned passive suspension,vertical,roll,and pitch accelerations are reduced by 14.13%,13.02%and 13.08%,respectively,significantly improving ride comfort.Additionally,the system effectively mitigates rollover risk,achieving reductions in roll angle,roll speed,and roll acceleration by 19.69%,16.40%,and 29.96%,respectively,thereby greatly enhancing vehicle safety.Overall,the proposed switching control strategy achieves a successful balance between ride comfort and handling stability,enhancing overall driving performance. 展开更多
关键词 Full-car suspension Ride comfort Handling stability Modal energy method Rollover risk indicators
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Linear WDE for performance enhancement of MIMO-OFDM system in the presence of Co-CFO
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作者 Khaled Ramadan Emad S.Hassan 《Defence Technology(防务技术)》 2025年第9期51-66,共16页
The Discrete Walsh Hadamard Transform(DWHT)has emerged as an efficient alternative to the Discrete Fourier Transform(DFT)for Orthogonal Frequency Division Multiplexing(OFDM)implementations,particularly in handling cha... The Discrete Walsh Hadamard Transform(DWHT)has emerged as an efficient alternative to the Discrete Fourier Transform(DFT)for Orthogonal Frequency Division Multiplexing(OFDM)implementations,particularly in handling channel impairments.In this article,we proposed an efficient Joint Low Complexity Regularized Zero Forcing-Wavelet Domain Equalizer(JLCRLZF-WDE)to replace the traditional Frequency Domain Equalizer(FDE)in DWHT-OFDM systems.Unlike FDE,which requires additional DFT and Inverse DFT(IDFT)computations,the proposed JLCRLZF-WDE directly operates in the Walsh domain,effectively mitigating the computational overhead.The derivation of the proposed JLCRLZF-WDE equations take the effect of the channel,Co-Carrier Frequency Offset(Co-CFO),as well as the noise into account.During the derivation of the system model equations,we assume a MultipleInput-Multiple-Output(MIMO)-OFDM communication system through a Rayleigh fading channel.The Bit Error Rate(BER)performance and computational complexity of the proposed and the conventional algorithms are compared,indicating the significance of the proposed algorithm.Simulation results confirm the superiority of the proposed equalizer,demonstrating a 23.68%±28.4%reduction in computational complexity compared to Minimum Mean Square Error(LMMSE)-FDE based on DFT,while maintaining comparable BER performance at various MIMO configuration.Furthermore,at a BER of 10^(-4),the JLCRLZF-WDE achieves performance parity with conventional Walsh domain LMMSE equalizers,whereas other equalizers require an additional Signal-to-Noise Ratio(SNR)of 3.06 d B to achieve the same performance. 展开更多
关键词 DWHT WDE FDE OFDM Co-CFO
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A Security Operation and Event Management(SOEM)Platform for Critical Infrastructures Protection
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作者 Roberto Caviglia Daniyar Aliaskharov +3 位作者 Alessio Aceti Mila Dalla Preda Paola Girdinio Giovanni Battista Gaggero 《Computers, Materials & Continua》 2025年第12期5327-5340,共14页
Industrial Control Systems(ICS)in Operational Technology(OT)environments face unique cybersecurity challenges due to legacy systems,critical operational needs,and incompatibility with standard IT security practices.To... Industrial Control Systems(ICS)in Operational Technology(OT)environments face unique cybersecurity challenges due to legacy systems,critical operational needs,and incompatibility with standard IT security practices.To address these challenges,this paper presents the Security Operation and Event Management(SOEM)platform,a software designed to support Security Operations Centers(SOCs)in reaching full visibility of OT environments.SOEM integrates diverse log sources and intrusion detection systems,including logs generated by the control system itself and additional on-the-shelf products,to enhance situational awareness and enable rapid incident response.The pilot project was carried out within the funded project SOC-OT-IGE from the“Centro di Competenza Start 4.0”and is being developed in partnership with Ansaldo Energia and HWG Sababa.The validation has been conducted in a real-world pilot project.Thanks to the mapping to requirements for compliance with IEC 62443,the platform demonstrates its effectiveness through defined key performance indicators(KPIs).This work bridges the gap between IT-centric SOC methodologies and the specialized needs of industrial cybersecurity. 展开更多
关键词 CYBERSECURITY MONITORING intrusion detection SIEM SOC
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Intelligent Sapling Shield:An Autonomous System for Sustainable Plant Care
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作者 Vijay Mane Harshal Ambadas Durge +7 位作者 Medha Wyawahare Siddharth Bhorge Kirti Wanjale Ashwini Barbadekar Milind Kamble Chin-Shiuh Shieh Rupali Atul Mahajan Rajesh Dey 《Journal of Environmental & Earth Sciences》 2025年第9期61-75,共15页
Plant health is increasingly threatened by environmental stressors,improper irrigation practices,and animal interference,leading to decreased growth and vitality.Current solutions often fail to integrate autonomous ir... Plant health is increasingly threatened by environmental stressors,improper irrigation practices,and animal interference,leading to decreased growth and vitality.Current solutions often fail to integrate autonomous irrigation with effective deterrent mechanisms in a single system.This paper presents the Intelligent Sapling Shield,an innovative device designed to enhance plant protection and optimize growth conditions.The system features an autonomous soil moisture regulation mechanism to optimize water usage,reducing wastage and irrigation costs,while a vibrational deterrent system mitigates animal interference,preventing crop damage.Constructed from plastic mesh,the device ensures proper sunlight exposure,airflow,and shade,with an integrated waterproof LED strip for night-time illumination.Results demonstrate that the system maintains optimal soil moisture levels,reducing water consumption compared to traditional irrigation methods.Additionally,automated plant care minimizes labour requirements,ensuring consistent hydration and protection while enhancing crop resilience and yield.The design emphasizes affordability,portability,and ease of installation,making it suitable for both small-scale urban gardening and large-scale agricultural deployment.Its modular structure allows for customization depending on plant type and environmental conditions,further extending its applicability.By integrating irrigation efficiency,protective deterrence,and energy-efficient illumination,the Intelligent Sapling Shield creates a holistic solution that addresses multiple challenges faced in plant cultivation.By promoting cost-effective,resource-efficient,and sustainable agricultural practices,the Intelligent Sapling Shield contributes to urban greening initiatives and biodiversity conservation,supporting long-term ecological sustainability and offering significant potential for future smart farming innovations. 展开更多
关键词 Smart Farming Precision Agriculture Agricultural Resource Optimization Agricultural Productivity
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A robust MP-ADRC-based strategy for uncertain minimum phase systems
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作者 Josiel A.Gouvêa Alessandro R.L.Zachi +1 位作者 Lúcio M.Fernandes Tiago Roux Oliveira 《Control Theory and Technology》 2025年第3期345-363,共19页
This paper proposes an extension of the Modified-Plant ADRC(MP-ADRC)strategy to broaden its application to minimum phase dynamical systems.The main features of the MP-ADRC method are the inclusion of a constant gain i... This paper proposes an extension of the Modified-Plant ADRC(MP-ADRC)strategy to broaden its application to minimum phase dynamical systems.The main features of the MP-ADRC method are the inclusion of a constant gain in series with the plant output error and a linear filter in parallel with the overall error system.These structural changes do not influence the input/output dynamics of the original plant,but are intentionally introduced to modify the dynamics to be estimated by the extended state observer(ESO)and,thus,promote an increase in the robustness of the method.Some advantages can also be attributed to the proposed methodology,such as(i)the design procedures of both the controller and the ESO only require knowledge of the sign(±)of the plant input channel coefficient(or control gain);(ii)the plant control input is generated directly by a single ESO state variable.Despite the advantages and the characteristics of MP-ADRC mentioned earlier,closed-loop stability cannot be guaranteed when it is applied to dynamical systems that have finite zeros.To overcome this difficulty,this work introduces an extension in the MP-ADRC method.It basically consists of rewriting the minimum phase plant dynamics according to its relative order,and then follows with the design of the ESO by conveniently increasing the number of ESO state variables.The simulation results are also presented to illustrate the application of the proposed method. 展开更多
关键词 Modified-plant ADRC Uncertain systems Minimum phase plants Robust control Extended state observer
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