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磁流变阻尼器多目标靶向抑制四跨转子轴系过临界转速振动实验研究

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北京化工大学学报（自然科学版） 2017年第2期44卷 95-102页

作者：杨秀峰何立东华陆工程科技有限公司西安710065 北京化工大学化工安全教育部工程研究中心北京100029

针对四跨转子轴系过临界转速易发生振动过大且各跨转子之间耦合振动复杂的问题,研究了基于磁流变阻尼器的多目标靶向在线振动控制方法。搭建四跨转子轴系实验台,设计新型磁流变阻尼器并应用于自主开发的多目标靶向在线控制系统。模拟试... 详细信息

针对四跨转子轴系过临界转速易发生振动过大且各跨转子之间耦合振动复杂的问题,研究了基于磁流变阻尼器的多目标靶向在线振动控制方法。搭建四跨转子轴系实验台,设计新型磁流变阻尼器并应用于自主开发的多目标靶向在线控制系统。模拟试车过程,研究了通入磁流变阻尼器内不同大小电流时,四跨转子轴系各跨转子振动的变化情况;由于四跨转子轴系过临界转速时耦合振动剧烈,因此提出基于转速的多目标靶向在线控制方法,采用在轴系中各跨转子临界转速附近开启、非临界转速关闭阻尼器的靶向分段控制策略,来实现在线抑制转子轴系过各阶临界转速时的振动。结果表明:磁流变阻尼器能抑制各跨转子过临界转速时的振动,且电流较大时抑振效果较好;应用带有多目标靶向在线控制系统的磁流变阻尼器能使四跨转子轴系在全转速范围振动较小,运行平稳。

关键词：磁流变阻尼器临界转速四跨转子轴系多目标靶向在线控制

For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation Technology

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China Communications 2024年第2期21卷 85-95页

作者： Chengjie Li lidong Zhu Zhen Zhang The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and Technology(Southwest Minzu University)Chengdu 610000China National Key Laboratory of Science and Technology on Communications(University of Electronic Science and Technology of China) Chengdu 610000China College of Computer Science(Sichuan University) Chengdu 610000China

In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system.

关键词： blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction

A Support Data-Based Core-Set Selection Method for Signal Recognition

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China Communications 2024年第4期21卷 151-162页

作者： Yang Ying Zhu lidong Cao Changjie National Key Laboratory of Wireless Communications(University of Electronic Science and Technology of China) Chengdu 611731China College of Computer Science and Cyber Security(Chengdu University of Technology) Chengdu 610059China College of Mathmatics and Physics(Chengdu University of Technology) Chengdu 610059China

In recent years,deep learning-based signal recognition technology has gained attention and emerged as an important approach for safeguarding the electromagnetic ***,training deep learning-based classifiers on large signal datasets with redundant samples requires significant memory and high *** paper proposes a support databased core-set selection method(SD)for signal recognition,aiming to screen a representative subset that approximates the large signal ***,this subset can be identified by employing the labeled information during the early stages of model training,as some training samples are labeled as supporting data *** support data is crucial for model training and can be found using a border sample *** results demonstrate that the SD method minimizes the impact on model recognition performance while reducing the dataset size,and outperforms five other state-of-the-art core-set selection methods when the fraction of training sample kept is less than or equal to 0.3 on the RML2.16.04C dataset or 0.5 on the RML2. *** SD method is particularly helpful for signal recognition tasks with limited memory and computing resources.

关键词： core-set selection deep learning model training signal recognition support data

Recycling the spent electronic materials to construct a highperformance Cu_(1.94)S/ZnS heterostructure anode of sodium-ion batteries

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Nano Research 2024年第5期17卷 4006-4015页

作者： Xiaowei He Tianshuai Wang lidong Tian Qiuyu Zhang School of Chemistry and Chemical Engineering Xi’an Key Laboratory of Functional Organic Porous MaterialsKey Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China Chongqing Science and Technology Innovation Center of Northwestern Polytechnical University Chongqing 401135China College of Materials Science and Engineering Xi’an University Science and TechnologyXi’an 710054China

Heterostructure engineering by coupling different nanocrystals has received extensive attention because it can enhance the reaction kinetics of the anode of sodium-ion batteries(SIBs).However,constructing high-quality heterostructure anode materials through green and environmentally friendly methods remains a ***,we have proposed a simple one-step method by recycling the electronic waste metal materials to synthesize the Cu_(1.94)S/ZnS heterostructure *** with the experimental analysis and first principle calculations,we find that the synergistic effect of different components in heterostructure structures can significantly enhance the reversible capacity and rate performance of anode *** on the constructed Cu_(1.94)S/ZnS anode,we obtain a superior reversible capacity of 440 mAh·g^(-1) at 100 mA·g^(-1) and 335 mAh·g^(-1) after 3000 cycles at 2.00 mA·g^(-1).Our work sheds new light on designing high-rate and capacity anodes for SIBs through the greenness synthesis method.

关键词： sodium-ion batteries heterostructure reversible capacity environmentally synthesis process

Convolutional neural network adaptation and optimization method in SIMT computing mode

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 105-112页

作者： Feng Zhenfu Zhang Yaying Yang Lele Xing lidong School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

For studying and optimizing the performance of general-purpose computing on graphics processing units(GPGPU)based on single instruction multiple threads(SIMT)processor about the neural network application,this work contributes a self-developed SIMT processor named Pomelo and correlated assembly *** parallel mechanism of SIMT computing mode and self-developed Pomelo processor is briefly introduced.A common convolutional neural network(CNN)is built to verify the compatibility and functionality of the Pomelo *** computing flow with task level and hardware level optimization is adopted on the Pomelo processor.A specific algorithm for organizing a Z-shaped memory structure is developed,which addresses reducing memory access in mass data computing *** the above-combined adaptation and optimization strategy,the experimental result demonstrates that reducing memory access in SIMT computing mode plays a crucial role in improving performance.A 6.52.times performance is achieved on the 4 processing elements case.

关键词： parallel computing single instruction multiple threads(SIMT) convolutional neural network(CNN) memory optimization

Design and implementation of a multi-tile parallel scanning rasterization accelerator

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 94-104页

作者： Xing lidong Guo Qiang Peng Xinlong Feng Zhenfu School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

In the design of a graphic processing unit(GPU),the processing speed of triangle rasterization is an important factor that determines the performance of the *** architecture of a multi-tile parallel-scan rasterization accelerator was proposed in this *** accelerator uses a bounding box algorithm to improve scanning *** rasterizes multiple tiles in parallel and scans multiple lines at the same time within each *** highly parallel approach drastically improves the performance of *** the 65 nm process standard cell library of Semiconductor Manufacturing International Corporation(SMIC),the accelerator can be synthesized to a maximum clock frequency of 2.0 *** implementation on the Genesys2.field programmable gate array(FPGA)board fully verifies the functionality of the *** implementation shows a significant improvement in rendering speed and efficiency and proves its suitability for high-performance rasterization.

关键词： graphic processing unit(GPU) rasterization multi-tile parallelism

Energy-Efficient Traffic Offloading for RSMA-Based Hybrid Satellite Terrestrial Networks with Deep Reinforcement Learning

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China Communications 2024年第2期21卷 49-58页

作者： Qingmiao Zhang lidong Zhu Yanyan Chen Shan Jiang National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China The Higher Educational Key Laboratory for Flexible Manufacturing Equipment Integration of Fujian Province Xiamen Institute of TechnologyXiamen 361021China China Mobile(Jiangxi)Communications Group Co. LtdYichun 336000China

As the demands of massive connections and vast coverage rapidly grow in the next wireless communication networks, rate splitting multiple access(RSMA) is considered to be the new promising access scheme since it can provide higher efficiency with limited spectrum resources. In this paper, combining spectrum splitting with rate splitting, we propose to allocate resources with traffic offloading in hybrid satellite terrestrial networks. A novel deep reinforcement learning method is adopted to solve this challenging non-convex problem. However, the neverending learning process could prohibit its practical implementation. Therefore, we introduce the switch mechanism to avoid unnecessary learning. Additionally, the QoS constraint in the scheme can rule out unsuccessful transmission. The simulation results validates the energy efficiency performance and the convergence speed of the proposed algorithm.

关键词： deep reinforcement learning energy efficiency hybrid satellite terrestrial networks rate splitting multiple access traffic offloading

Unlocking supercapacitive energy storage potential:Catalyzing electrochemically inactive manganese oxides to active MnO_(2.via heterostructure reconstruction

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Nano Research 2024年第7期17卷 5897-5906页

作者： Baohong Zhang Tao Jiang Xinyan Zhou Xiaoyu Fan Binbin Jia lidong Li School of Chemistry Beihang UniversityBeijing 100191China College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChinaThree Gorges UniversityYichang 443002China Chinese Academy of Sciences(CAS)Key Laboratory of Nanosystem and Hierarchy Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China Shanghai GTX Semiconductor Co. Ltd.Shanghai 201806China

Advancing supercapacitor system performance hinges on the innovation of novel electrode materials seamlessly integrated within distinct ***,we introduce a direct approach for crafting nanorod arrays featuring crystalline/amorphous CuO/MnO_(2.−*** reconfigured heterostructure results in an elevated content of electrochemically active MnO_(2..The nanorod arrays serve as efficient capacitive anodes and are easily prepared via low-potential electrochemical *** resulting structure spontaneously forms a p–n heterojunction,developing a built-in electric field that dramatically facilitates the charge transport *** intrinsic electric field,in conjunction with the crystalline/amorphous architecture,enables a large capacitance of 1.0 F·cm^(−2.at 1.0 mA·cm^(−2.,an ultrahigh rate capability of approximately 85.4%at 15 mA·cm^(−2.,and stable cycling performance with 92.4%retention after 10,000 *** calculations reveal that the presence of heterojunctions allows for the optimization of the electronic structure of this composite,leading to improved conductivity and optimized OH−adsorption *** work provides new insights into the rational design of heterogeneous nanostructures,which hold great potential in energy storage applications.

关键词： reconfiguration active MnO_(2. crystalline/amorphous structure p-n heterojunction supercapacitor

Estimating the optimal vegetation coverage for the dominant tree and shrub species over China's northwest drylands

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Science China Earth Sciences 2024年第5期67卷 1500-1517页

作者： Zhongdian ZHANG Xiaoxu JIA Ping ZHU Mingbin HUANG lidong REN Ming’an SHAO School of Geographic Sciences Xinyang Normal UniversityXinyang 464000China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Yellow River Delta Modern Agricultural Engineering Laboratory Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China

Anthropogenic revegetation is an effective way to control soil erosion and restore degraded ecosystems in China's northwest drylands(NWD).However,excessive vegetation cover expansion has long been known to increase evapotranspiration,leading to reduced local water availability,which can in turn threaten the health and services of restored *** the optimal vegetation coverage(OVC)is critical for balancing the trade-off between plant growth and water consumption in water-stressed areas,yet quantitative assessments over the entire NWD are still *** this study,a modified Biome BioGeochemical Cycles(Biome-BGC)model was used to simulate the long-term(1961–2.2.)dynamics of actual evapotranspiration(ET_(a)),net primary productivity(NPP),and leaf area index(LAI)for the dominant non-native tree(*** and ***)and shrub(*** and ***)species at 2.6 meteorological sites over *** modified model incorporated the Richards equation to simulate transient unsaturated water flow in a multilayer soil module,and both soil and eco-physiological parameters required by the model were validated using field-observed ETadata for each *** distributions of OVC(given by the mean maximum LAI,LAI_(max))for the dominant species were determined within three hydrogeomorphic sub-areas(i.e.,the loess hilly-gully sub-area,the windy and sandy sub-area,and the desert sub-area).The modified Biome-BGC model performed well in terms of simulating ET_(a) dynamics for the four plant *** distributions of mean ET_a,NPP,and LAI_(max)generally exhibited patterns similar to mean annual precipitation(MAP).In the loess hilly-gully sub-area(MAP:2.0 to 710 mm),the OVC respectively ranged from 1.7 to 2.9 and 0.8 to 2.9 for *** and *** the windy and sandy sub-area(MAP:135 to 500 mm),the OVC ranged from 0.3 to 3.3,0.5 to 2.6 and 0.6 to 2.1for ***,*** and ***,*** the desert sub-

关键词： Optimal vegetation coverage Water balance Leaf area index Biome-BGC model Dryland