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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 511-524页

作者： Lei Zhenbo Liu Gang Wang Hui Hui Yi School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in mountain Area Chongqing UniversityMinistry of EducationChongqing 400045China

With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly *** particular,seismic excitation can create a resonance response and cause excessive vibration of the *** investigate the vibration attenuation performance of the WTT under seismic excitations,a novel passive vibration control device,called a prestressed tuned mass damper(PS-TmD),is presented in this ***,a mathematical model is established based on structural dynamics under seismic ***,the mathematical analytical expression of the dynamic coefficient is deduced,and the parameter design method is obtained by system tuning ***,based on a theoretical analysis and parameter design,the numerical results showed that the PS-TmD was able to effectively mitigate the resonance under the harmonic basal ***,the time-history analysis method is used to verify the effectiveness of the traditional pendulum tuned mass damper(PTmD)and the novel PS-TmD device,and the results indicate that the vibration attenuation performance of the PS-TmD is better than the *** addition,the PS-TmD avoids the nonlinear effect due to the large oscillation angle,and has the potential to dissipate hysteretic energy under seismic excitation.

关键词： wind turbine tower prestressed tuned mass damper vibration control seismic excitation numerical simulation

Compound Product of Hypermatrices

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Journal of Systems science & Complexity 2024年第1期37卷 169-183页

作者： CHENG Daizhan mENG min ZHANG Xiao JI Zhengping Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Control science and Engineering School of Electronics and Information EngineeringTongji UniversityShanghai 201210China National Center for mathematics and Interdisciplinary sciences Chinese Academy of SciencesBeijing 100190China School of mathematical sciences University of Chinese Academy of SciencesBeijing 100149China.

The semi-tensor product(STP)of matrices is generalized to multidimensional arrays,called the compound product of *** product is first defined for three-dimensional hypermatrices with compatible orders and then extended to general *** different types of hyperdeterminants are introduced and certain properties are *** Lie groups and Lie algebras corresponding to the hypermatrix products are ***,these results are applied to dynamical systems.

关键词： Compound semi-tensor product hyperdeterminants hypereigenvalues and hypereigenvectors hypergeneral linear groups hypermatrices.

Analytical libration control law for electrodynamic tether system with current constraint

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Astrodynamics 2024年第2期8卷 237-246页

作者： Shidong Xu Ti Chen Hao Wen Dongping Jin State Key Laboratory of mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

This study focuses on stabilizing the libration dynamics of an electrodynamic tether system(EDTS)using generalized torques induced by the Lorentz *** contrast to existing numerical optimization methods,a novel analytical feedback control law is developed to stabilize the in-plane and out-of-plane motions of a tether by modulating the electric current *** saturation constraint on the current is accounted for by adding an auxiliary dynamic system to the *** enhance the robustness of the proposed controller,multiple perturbations of the orbital dynamics,modeling uncertainties,and external disturbances are approximated using a neural network in which the weighting matrix and approximation error are estimated simultaneously,such that these perturbations are well compensated for during the control design of the ***,a dynamically scaled generalized inverse is utilized to address the singular matrix in the control *** closed-loop system is proven to be ultimately bounded based on Lyapunov stability ***,numerical simulations are performed to demonstrate the effectiveness of the proposed analytical control law.

关键词： electrodynamic tether system(EDTS) libration dynamics analytical control current constraint

Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer modeling in Engineering & sciences 2024年第7期140卷 665-684页

作者： Xue-Qin Li Lu-Kai Song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

Free-walking:Pedestrian inertial navigation based on dual foot-mounted ImU

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Defence Technology（防务技术） 2024年第3期33卷 573-587页

作者： Qu Wang meixia Fu Jianquan Wang Lei Sun Rong Huang Xianda Li Zhuqing Jiang Yan Huang Changhui Jiang School of Automation science and Electrical Engineering University of Science and Technology BeijingBeijing100083China Shunde Innovation School University of Science and Technology BeijingFo Shan528399China Research Institute of china Unicom Beijing100190China School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing100876China Department of Automation Tsinghua University Beijing100084China GEOLOC Laboratory Universite Gustave EiffelParis77454France

The inertial navigation system(INS),which is frequently used in emergency rescue operations and other situations,has the benefits of not relying on infrastructure,high positioning frequency,and strong real-time ***,the intricate and unpredictable pedestrian motion patterns lead the INS localization error to significantly diverge with *** paper aims to enhance the accuracy of zero-velocity interval(ZVI)detection and reduce the heading and altitude drift of foot-mounted INS via deep learning and equation constraint of dual *** at the observational noise problem of low-cost inertial sensors,we utilize a denoising autoencoder to automatically eliminate the inherent *** at the problem that inaccurate detection of the ZVI detection results in obvious displacement error,we propose a sample-level ZVI detection algorithm based on the U-Net neural network,which effectively solves the problem of mislabeling caused by sliding *** at the problem that Zero-Velocity Update(ZUPT)cannot suppress heading and altitude error,we propose a bipedal INS method based on the equation constraint and ellipsoid constraint,which uses foot-to-foot distance as a new observation to correct heading and altitude *** conduct extensive and well-designed experiments to evaluate the performance of the proposed *** experimental results indicate that the position error of our proposed method did not exceed 0.83% of the total traveled distance.

关键词： Indoor positioning Inertial navigation system(INS) Zero-velocity update(ZUPT) Internet of things(IoTs) Location-based service(LBS)

An Intelligent Sensor Data Preprocessing method for OCT Fundus Image Watermarking Using an RCNN

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Computer modeling in Engineering & sciences 2024年第2期138卷 1549-1561页

作者： Jialun Lin Qiong Chen College of Biomedical Information and Engineering Hainan Medical UniversityHaikou571199China TJ-YZ School of Network science Haikou University of EconomicsHaikou571127China Department of Earth System science Ministry of Education Key Laboratory for Earth SystemModelingInstitute forGlobal Change StudiesTsinghua UniversityBeijing100084China

Watermarks can provide reliable and secure copyright protection for optical coherence tomography(OCT)fundus *** effective image segmentation is helpful for promoting OCT image ***,OCT images have a large amount of low-quality data,which seriously affects the performance of ***,this paper proposes an effective segmentation method for OCT fundus image watermarking using a rough convolutional neural network(RCNN).First,the rough-set-based feature discretization module is designed to preprocess the input ***,a dual attention mechanism for feature channels and spatial regions in the CNN is added to enable the model to adaptively select important information for ***,the refinement module for enhancing the extraction power of multi-scale information is added to improve the edge accuracy in *** is compared with CE-Net and multiResUNet on 83 gold standard 3D retinal OCT data *** average dice similarly coefficient(DSC)obtained by RCNN is 6%higher than that of *** average 95 percent Hausdorff distance(95HD)and average symmetric surface distance(ASD)obtained by RCNN are 32.4%and 33.3%lower than those of multiResUNet,*** also evaluate the effect of feature discretization,as well as analyze the initial learning rate of RCNN and conduct ablation experiments with the four different *** experimental results indicate that our method can improve the segmentation accuracy of OCT fundus images,providing strong support for its application in medical image watermarking.

关键词： Watermarks image segmentation rough convolutional neural network attentionmechanism feature discretization

A Blockchain-Based Game Approach to multi-microgrid Energy Dispatch

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工程与科学中的计算机建模(英文) 2024年第1期138卷 845-863页

作者： Zhikang Wang Chengxuan Wang Wendi Wu Cheng Sun Zhengtian Wu School of Electronic and Information Engineering Suzhou University of Science and TechnologySuzhou215123China

As the current global environment is deteriorating,distributed renewable energy is gradually becoming an important member of the energy ***,as a decentralized distributed ledger with decentralization,traceability and tamper-proof features,is an importantway to achieve efficient consumption andmulti-party supply of new *** this article,we establish a blockchain-based mathematical model of multiple microgrids and microgrid aggregators’revenue,consider the degree of microgrid users’preference for electricity thus increasing users’reliance on the blockchainmarket,and apply the one-master-multiple-slave Stackelberg game theory to solve the energy dispatching strategy when each market entity pursues the maximum *** simulation results show that the blockchain-based dynamic game of the multi-microgrid market can effectively increase the revenue of both microgrids and aggregators and improve the utilization of renewable energy.

关键词： multi-microgrid blockchain stackelberg game energy scheduling

Biomimetic natural biomaterials for tissue engineering and regenerative medicine:new biosynthesis methods,recent advances,and emerging applications

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military medical Research 2024年第1期11卷 50-79页

作者： Shuai Liu Jiang-ming Yu Yan-Chang Gan Xiao-Zhong Qiu Zhe-Chen Gao Huan Wang Shi-Xuan Chen Yuan Xiong Guo-Hui Liu Si-En Lin Alec mcCarthy Johnson V.John Dai-Xu Wei Hong-Hao Hou Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering the Fifth Affiliated HospitalSchool of Basic Medical ScienceSouthern Medical UniversityGuangzhou 510900China Department of Orthopedics Tongren HospitalShanghai Jiao Tong UniversityShanghai 200336China The Eighth Affiliated Hospital Sun Yat-Sen UniversityShenzhen 518033GuangdongChina Engineering Research Center of Clinical Functional materials and Diagnosis&Treatment Devices of Zhejiang Province Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhou 325011ZhejiangChina Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Orthopaedics and Traumatology Faculty of Medicinethe Chinese University of Hong KongHong Kong SAR 999077China Department of Functional materials Terasaki Institute for Biomedical InnovationLos AngelesCA 90064USA mary&Dick Holland Regenerative medicine Program College of MedicineUniversity of Nebraska Medical CenterOmahaNE 68130USA Zigong Affiliated Hospital of Southwest medical University Zigong Psychiatric Research CenterZigong Institute of Brain ScienceZigong 643002SichuanChina Key Laboratory of Resource Biology and Biotechnology in Western china Ministry of EducationSchool of MedicineDepartment of Life Sciences and MedicineNorthwest UniversityXi’an 710127China

Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative *** contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECm).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative *** paper provides an overview for recent progress of biomimetic natural biomaterials(BNBms),including advances in their preparation,functionality,potential applications and future *** highlight recent advances in the fabrication of BNBms and outline general strategies for functionalizing and tailoring the BNBms with various biological and physicochemical characteristics of native ***,we offer an overview of recent key advances in the functionalization and applications of versatile BNBms for TE ***,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field.

关键词： Biomimic Scaffold Biosynthesis Natural biomaterial Tissue engineering

mitigating Straggler Effect in Federated Learning Based on Reconfigurable Intelligent Surface over Internet of Vehicles

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china Communications 2024年第8期21卷 62-78页

作者： Li Zejun Wu Hao Lu Yunlong Dai Yueyue Ai Bo School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China Frontiers science Center for Smart High-Speed Railway System Beijing 100044China Beijing Engineering Research Center of High-Speed Railway Broadband mobile Communications Beijing 100044China Research Center of 6G mobile Communications School of Cyber Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

To protect vehicular privacy and speed up the execution of tasks,federated learning is introduced in the Internet of Vehicles(IoV)where users execute model training locally and upload local models to the base station without massive raw data ***,heterogeneous computing and communication resources of vehicles cause straggler effect which weakens the reliability of federated *** out vehicles with limited resources confines the training *** a result,the accuracy and applicability of federated learning models will be *** mitigate the straggler effect and improve performance of federated learning,we propose a reconfigurable intelligent surface(RIS)-assisted federated learning framework to enhance the communication reliability for parameter transmission in the ***,we optimize the phase shift of RIS to achieve a more reliable communication *** addition,we define vehicular competence to measure both vehicular trustworthiness and *** on the vehicular competence,the straggler effect is mitigated where training tasks of computing stragglers are offloaded to surrounding vehicles with high *** experiment results verify that our proposed framework can improve the reliability of federated learning in terms of computing and communication in the IoV.

关键词： reliable federated learning RIS straggler effect vehicular competence

Solar-powered methanol synthesis from COhydrogenation with high conversion and selectivity

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science china Chemistry 2024年

作者： Lingzhen Zeng Yongfang Sun Tingting Wang Zeyan Cen maolin Wang Oriol Angurell meng Wang Ding ma Beijing National Laboratory for molecular sciences New Cornerstone Science LaboratoryCollege of Chemistry and Molecular EngineeringPeking University Leitat managing Technologies Parc Cientific de BarcelonaEdifici Clúster IIPlanta 4Carrer Baldiri Reixac

methanol synthesis via CO2hydrogenation stands as a pivotal avenue for CO2conversion and fixation,garnering extensive *** reactor configurations and energy supplies,alongside a spectrum of catalyst formulations,have been developed to enhance reaction metrics including conversion,selectivity,productivity,and *** state-of-the-art Cu-based catalysts from thermal catalysis into a photothermal reactor yielded notable results,achieving an overall CO2conversion of 98%and methanol selectivity of 86%.Utilizing the liquid out/gas in concept （LOGIC） reactor,in which only the catalyst bed is irradiated to raise its temperature,facilitated the condensation of products （H2O and CH3OH）,due to their low vapor *** lower concentration of products in vapor phases ensured the continuous progress of the *** synergistic integration of reactor design and catalyst fabrication could capitalize on the strengths of both components and lead to enhanced performance in methanol synthesis.

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