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Deployment of Edge Computing Nodes in IoT:Effective Implementation of Simulated Annealing Method Based on User Location

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China Communications 2024年第1期21卷 279-296页

作者： Junhui Zhao ziyang Zhang Zhenghao Yi Xiaoting Ma Qingmiao Zhang School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China School of Information Engineering East China Jiaotong UniversityNanchang 330013China

Edge computing paradigm for 5G architecture has been considered as one of the most effective ways to realize low latency and highly reliable communication,which brings computing tasks and network resources to the edge of *** deployment of edge computing nodes is a key factor affecting the service performance of edge computing *** this paper,we propose a method for deploying edge computing nodes based on user *** the combination of Simulation of Urban Mobility(SUMO)and Network Simulator-3(NS-3),a simulation platform is built to generate data of hotspot areas in Io T *** effectively using the data generated by the communication between users in Io T scenario,the location area of the user terminal can be *** this basis,the deployment problem is expressed as a mixed integer linear problem,which can be solved by Simulated Annealing(SA)*** analysis of the results shows that,compared with the traditional method,the proposed method has faster convergence speed and better performance.

关键词： deployment problem edge computing internet of things machine learning

Active disturbance rejection distributed secondary control for DC microgrids

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High Voltage 2024年第1期9卷 241-251页

作者： Jianlin Li Honghao You Shuo Liu Xingchen Li ziyang Ding Fei Zou National User-Side Energy Storage Innovation Research and Development Center North China University of TechnologyBeijingChina

A novel control scheme is presented to eliminate the negative effects of communication disturbances,which introduces active disturbance rejection control(ADRC)in the control strategy design to achieve the objectives of the restoration of the bus voltage and the sharing of the power even in the presence of disturbances and delays in ***,its dynamic disturbance decoupling feature is used to realise the decoupling between power and voltage,so that the proposed controller only exchanges power information with its neighbours,reducing the communication burden and simplifying control *** control performance of the strategy is verified by employing steady-state *** impact of controller parameters is studied by establishing a small signal ***,both simulation cases and experimental tests prove the feasibility of this scheme.

关键词： Active disturbance establishing

Structure and Catalytic Activity of Nickel-substituted Mica- montmorillonite Clay Crosslinked with NH2(C3H3)Si(OC2H5)2

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Chemical Research in Chinese Universities 1990年第1期6卷 32-40页

作者： Jiang Dazhen, Cai Hui, Liu ziyang and zhou Qun (Department of Chemistry, Jilin University, Changchun)Min Enze and He Mingyuan (Research Institute of Petroleum Processing, Beijing)

Nickel-substituted mica-montmorillonite clays(Ni-SMM) were synthesized, the pillared clays, Si-Ni-SMM, were prepared from the Ni-SMM intercalated with NH2(C3H5)Si(OC2H5)*** pillar perhaps consists of tripolymer of silica according to the judgement from the pillar height (8. 5A ) data. The results of IR, ESR and XRD indicate that the hydroxy group in the octahedral layer is attacked by crosslinking agent. Thus the silicon oxide pillars become directly linked via oxygen to the nickel atoms in the octahedral layer. The change of the ratio of Lewis to Bronsted acidity on Si-Ni-SMM reduced at 400℃ by H2 shows that the hydrogenating component such as Ni in the framework of SMM plays an important role in catalyst deactivation in H, atmosphere. This kind of action may be due to spilled- over hydrogen.

关键词： Nickel-substituted mica-montmorillonite Silicon pillar Acidity cracking

Low-power soft transistors triggering revolutionary electronics

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The Innovation 2024年第3期5卷 21-22页

作者： ziyang Liu Yaoshen Zhao Zhigang Yin State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqing 400044China

Transistors have been reshaping our lives since their initial appearance in the *** the central element of logic gates and integrated circuits(chips),they undoubtedly play an incomparable role in promoting the development of computers,smartphones,flat panel displays,Internet of Things,and even all electronic or electrical *** past decades have witnessed dominant transistors usually made from inorganic semiconductors such as silicon materials and metal oxides,which are advantageous to achieve high mobility,fast switching speed,and excellent ***,silicon transistors and metal oxide semiconductor field-effect transistors have been broadly used for electronic ***,these transistors are rigid and nearly approaching the fundamental limits on speed and power consumption,despite being manufactured at a much smaller scale to meet the projection of Moore’s *** future transistors with mechanical flexibility/robustness and low-power consumption are demanded,innovation in functional materials,device configurations,and integrated processing techniques to facilitate the evolution from rigid devices to soft,durable,and biocompatible devices is imperative.

关键词： approaching evolutionary doubt

Lightweight and high-security laser-based cotton tip pruning robot

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 98-108页

作者： Xuan'ang Guo ziyang Mao Zedong Shi Wei Lu School of Artificial Intelligence Nanjing Agricultural UniversityNanjing 210031China

Considering the current environmental pollution caused by chemical topping,plant damage caused by mechanical topping,and the high cost of manual topping,a laser-based cotton-tip pruning robot for field cotton was designed in this *** main advantages of this robot include its safety,light weight,low cost,and environmental ***,the structural design,measurement,and corresponding control system design of the robot were ***,a precise laser control method based on Yolov5 cotton top identification and the inverse kinematic solution of parallel robot rapid positioning were ***,the optimal laser irradiation wavelength and duration were ***,a laser-topping experiment was conducted,and the overall accuracy and recall rates for cotton identification were 98.3%and 99.3%,*** AP and mAP at the threshold value of 0.5 reached 99.3%and 78.8%,*** maximum positioning error of the jacking system is 2.6 mm,and the repeated positioning error is within±1.2 cm,which meets the accuracy requirements of laser ***-purple laser irradiation at 15 W and 405 nm for 22 s was the best topping *** the effects of cotton topping with and without manual topping,it can be seen that laser topping significantly improved the yield and *** with the photothermal response of the cotton topping,the feasibility of laser topping was verified both theoretically and *** laser-topping scheme proposed in this study exhibits high efficiency,environmental protection,and safety,as well as good application prospects.

关键词： laser topping parallel manipulator photothermal response object detection

Vibration and noise mechanism of a 110 kV transformer under DC bias based on finite element method

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Global Energy Interconnection 2024年第4期7卷 503-512页

作者： ziyang Li Xujun Lang Bo Yang Xiaolin Liu Hao Wang Zhang Li Shandong Electric Power Engineering Consulting Institute Co. Ltd.Jinan 250013P.R.China School of Electrical Engineering Shandong UniversityJinan 250061P.R.China

Global energy and environmental issues are becoming increasingly problematic,and the vibration and noise problem of 110 kV transformers,which are the most widely distributed,have attracted widespread attention from both inside and outside the *** bias is one of the main contributing factors to vibration noise during the normal operation of *** clarify the vibration and noise mechanism of a 110 kV transformer under a DC bias,a multi-field coupling model of a 110 kV transformer was established using the finite element *** electromagnetic,vibration,and noise characteristics during the DC bias process were compared and quantified through field circuit coupling in parallel with the power frequency of AC,harmonic,and DC power *** was found that a DC bias can cause significant distortions in the magnetic flux density,force,and displacement distributions of the core and *** contributions of the DC bias effect to the core and winding are different at Kdc=*** this point,the core approached saturation,and the increase in the core force and displacement ***,the saturation of the core increased the leakage flux,and the stress and displacement of the winding increased *** sound field distribution characteristics of the 110 kV transformer under a DC bias are related to the force *** the DC bias coefficient was 1.25,the noise sound pressure level reached 73.6 dB.

关键词： Transformer DC bias Vibration Noise

Research on aiming methods for small sample size shooting tests of two-dimensional trajectory correction fuse

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Defence Technology（防务技术） 2024年第3期33卷 506-517页

作者： Chen Liang Qiang Shen Zilong Deng Hongyun Li Wenyang Pu Lingyun Tian ziyang Lin School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse *** impact point easily deviates from the target,and thus the correction result cannot be readily ***,the cost of shooting tests is considerably high to conduct many tests for data *** address this issue,this study proposes an aiming method for shooting tests based on small sample *** proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion *** experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future.

关键词： Two-dimensional trajectory correction fuse Small sample size test Compatibility test KL divergence Fusion bayesian estimation

Intertwined depressive and cognitive trajectories and the risk of dementia and death in older adults:a competing risk analysis

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General Psychiatry 2024年第2期37卷 207-215页

作者： ziyang Ren Lirong Nie Yushan Du Jufen Liu Institute of Reproductive and Child Health/National Health Commission Key Laboratory of Reproductive Health Peking UniversityBeijingChina Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijingChina

Background Depressive symptoms and cognitive impairment often interact,rendering their associations *** date,their joint trajectories and associations with dementia and death remain *** To explore the interactions between depressive symptoms and cognitive function,their developmental trajectories and the associations with all-cause dementia,Alzheimer’s disease(AD)and all-cause death in older *** Data were from the Health and Retirement *** symptoms and cognitive function were measured using the 8-item Centre for Epidemiologic Studies Depression Scale and the Telephone Interview of Cognitive Status,***-cause dementia and AD were defined by self-reported or proxy-reported physician ***-cause death was determined by *** restricted cubic spline,group-based trajectory modelling and subdistribution hazard regression were *** Significant interactions between depressive symptoms and cognitive function in 2010 in their association with new-onset all-cause dementia and AD from 2010 to 2020 were found,especially in women(p for interaction<0.05).Independent trajectory analysis showed that emerging or high(vs no)depressive trajectories and poor or rapidly decreased cognitive trajectories(vs very good)from 1996 to 2010 were at significantly higher risk of subsequent all-cause dementia,AD and all-cause death.15 joint trajectories of depressive symptoms and cognitive function from 1996 to 2010 were determined,where rapidly decreased cognitive function was more common in those with no depressive *** with older adults with the trajectory of no depressive symptoms and very good cognitive function,those with the trajectory of no depressive symptoms but rapidly decreased cognitive function were much more likely to develop new-onset all-cause dementia and death,with subdistribution hazard ratios(95%confidence intervals)of 4.47(2.99 to 6.67)and 1.84(1.43 to 2.36),especially in wome

关键词： death analysis rendering

Anisotropic phonon dynamics in Dirac semimetal PtTe2 thin films enabled by helicity-dependent ultrafast light excitation

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Light(Science & Applications) 2024年第9期13卷 1888-1897页

作者： ziyang Li Yequan Chen Anke Song Jinzhong Zhang Rong Zhang Zongzhi Zhang Xuefeng Wang Key Laboratory of Micro and Nano Photonic Structures(MOE) School of Information Science and TechnologyFudan UniversityShanghaiChina Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials State Key Laboratory of Spintronics Devices and TechnologiesSchool of Electronic Science and EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjingChina Department of Physics School of Physics and Electronic ScienceEast China Normal UniversityShanghaiChina Department of Physics Xiamen UniversityXiamenChina

Coherent phonons have aroused considerable attention in condensed matter physics owing to their extraordinary capacity of reflecting and controlling the physical properties of ***,the investigation on the interaction between coherent phonons and other microscopic particles on the ultrafast timescale within topological systems continues to be an active and unresolved ***,we show the energy transfer of coherent optical phonons(COP)in Dirac semimetal PtTe2 thin films using ultrafast optical pump-probe ***,the helicitydependent light-driven anisotropic COP signals disclose their direct connection with the light-excited anisotropic spinpolarized electrons via an angular momentum ***,we observe the notable decreases in the COP oscillation frequency and the decay rate with increasing temperatures due to the anharmonic phonon-phonon scattering and electron-phonon scattering in the COP dissipation process,*** work paves the way for uncovering the coherent phonons in Dirac semimetals for the potential applications in optoelectronics and optospintronics.

关键词： spectroscopy. phonon Dirac