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双向隔离型AC-DC矩阵变换器最小开关损耗控制方法
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作者 梅杨 石仪 张家奇 《电工技术学报》 北大核心 2026年第4期1414-1424,共11页
为了实现双向隔离型AC-DC矩阵变换器(BIMC)的高效运行,该文提出一种最小开关损耗控制方法。基于双线电压调制策略,建立电力电子器件损耗模型,引入基于序列二次规划算法(SQP)的优化方法,以输入功率和移相角范围为限定条件,对开关损耗进... 为了实现双向隔离型AC-DC矩阵变换器(BIMC)的高效运行,该文提出一种最小开关损耗控制方法。基于双线电压调制策略,建立电力电子器件损耗模型,引入基于序列二次规划算法(SQP)的优化方法,以输入功率和移相角范围为限定条件,对开关损耗进行最小化寻优,实时计算最优的移相角组合,并应用于变换器的调制过程,以保证变换器的开关损耗最小。仿真和实验结果表明,采用所提出的控制方法可实现网侧电流为正弦电流,功率因数接近于1,直流侧电压与电流稳定,电流纹波率小于1%,且在较宽功率范围内,变换器效率均维持在94%以上,最高可达到96.89%。相较于传统的控制方法而言,所提方法在宽运行范围中均可以使电力电子器件的损耗最小。 展开更多
关键词 ac-DC矩阵变换器 双线电压调制策略 开关损耗 序列二次规划
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矩阵式隔离型AC-DC变换器的线性自抗扰控制
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作者 王晓雷 王铂钦 +1 位作者 郭飞亚 冯明鑫 《机电工程技术》 2026年第1期124-130,共7页
矩阵式隔离型AC-DC变换器属于无直流母线的单级AC-DC变换器类型,其省略了直流储能电容使结构更加紧凑,功率密度提高,同时采用高频变压器实现隔离。为了提高该拓扑结构输出侧的动态响应性能和抗干扰性能,提出了一种基于线性自抗扰控制(Li... 矩阵式隔离型AC-DC变换器属于无直流母线的单级AC-DC变换器类型,其省略了直流储能电容使结构更加紧凑,功率密度提高,同时采用高频变压器实现隔离。为了提高该拓扑结构输出侧的动态响应性能和抗干扰性能,提出了一种基于线性自抗扰控制(Linear Active Disturbance Rejection Control,LADRC)的双闭环控制器。通过对矩阵式隔离型AC-DC变换器拓扑结构进行建模得到数学模型,并在此基础上设计了LADRC双闭环控制方案。对该系统模型进行MATLAB/Simulink仿真实验,结果表明所提基于线性自抗扰的双闭环控制器比PI控制器的动态响应速度缩短10 ms,动态响应性能提升了40%,具备更快的动态响应速度;抗干扰试验结果表明,输出电压瞬态偏差缩小50%,响应时间缩短57%,具备更强的抗干扰能力,验证了该控制策略的正确性。 展开更多
关键词 矩阵变换器 线性自抗扰控制(LADRC) 双闭环控制 隔离型 ac-DC变换器
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转BtCry1Ac基因杨树的生物安全性评价
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作者 林昕怡 周星鲁 +3 位作者 张磊 王丽娟 安新民 胡建军 《林业科学》 北大核心 2026年第2期134-146,共13页
【目的】系统评价第1代转BtCry1Ac基因欧洲黑杨及其转基因杂交F1代京兴1号和京兴2号的生物安全性,重点分析外源基因表达和抗虫性状的稳定性,并探讨其对根际土壤微生物和林内生物多样性的潜在影响,为转BtCry1Ac基因抗虫杨树安全性评价和... 【目的】系统评价第1代转BtCry1Ac基因欧洲黑杨及其转基因杂交F1代京兴1号和京兴2号的生物安全性,重点分析外源基因表达和抗虫性状的稳定性,并探讨其对根际土壤微生物和林内生物多样性的潜在影响,为转BtCry1Ac基因抗虫杨树安全性评价和产业化应用提供科学依据。【方法】通过PCR和RT-qPCR技术验证转基因杨树目标基因稳定性,测定各无性系树高、胸径评价生长表现;采用美国白蛾幼虫饲喂各无性系叶片18天评价抗虫性;应用标准方法测定各无性系根际土壤pH值及主要养分含量;利用16S/ITS高通量测序解析土壤微生物群落组成与多样性,结合样方调查和马氏网法监测林下杂草及节肢动物群落结构。【结果】1)PCR和RT-qPCR检测结果明确BtCry1Ac基因在第1代转基因欧洲黑杨和F1代转基因杂交子代中稳定存在并表达,特异性条带为546 bp。2)生长调查表明,京兴1号和京兴2号的树高较对照108杨分别提高9.62%和7.56%,胸径分别提高17.57%和15.07%,但未达到显著性差异。3)室内饲虫试验表明,与对照108杨相比,京兴1号和京兴2号对美国白蛾幼虫的抗性显著增强,饲喂18天后幼虫死亡率分别提升116.24%和96.21%。4)根际土壤理化性质分析显示,除转基因无性系n208的根际土壤pH值显著升高外,有机质及氮、磷、钾养分含量在各无性系间无显著差异。5)土壤微生物群落研究表明,细菌与真菌门水平优势类群(变形菌门及子囊菌门)组成未受显著影响;各无性系间细菌和真菌群落结构的α多样性指数无统计学差异;β多样性分析揭示真菌群落结构存在显著组间分化,而细菌群落保持稳定。6)林下生物多样性调查记录到杂草8科14种、节肢动物6目22科,BtCry1Ac基因表达对杂草群落的物种丰富度、多样性、优势度和均匀度均未产生显著影响。转基因林地内目标害虫(鳞翅目)数量显著降低,但节肢动物群落整体结构与对照林地高度相似,关键多样性指数无显著变化。【结论】转BtCry1Ac基因杨树外源基因稳定存在并表现出较高抗虫性,未发现对土壤养分循环、微生物α多样性以及林下生物群落稳定性产生明显影响。杂交子代京兴1号、京兴2号有较好的抗虫优势,具有良好应用前景。本研究结果可为转基因杨树环境生物安全评价提供科学依据,建议开展长期监测以系统评价其对生态环境的影响。 展开更多
关键词 转基因杨树 BtCry1ac 抗虫性 生物多样性 土壤微生物 环境安全评价
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Computation and wireless resource management in 6G space-integrated-ground access networks 被引量:1
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作者 Ning Hui Qian Sun +2 位作者 Lin Tian Yuanyuan Wang Yiqing Zhou 《Digital Communications and Networks》 2025年第3期768-777,共10页
In 6th Generation Mobile Networks(6G),the Space-Integrated-Ground(SIG)Radio Access Network(RAN)promises seamless coverage and exceptionally high Quality of Service(QoS)for diverse services.However,achieving this neces... In 6th Generation Mobile Networks(6G),the Space-Integrated-Ground(SIG)Radio Access Network(RAN)promises seamless coverage and exceptionally high Quality of Service(QoS)for diverse services.However,achieving this necessitates effective management of computation and wireless resources tailored to the requirements of various services.The heterogeneity of computation resources and interference among shared wireless resources pose significant coordination and management challenges.To solve these problems,this work provides an overview of multi-dimensional resource management in 6G SIG RAN,including computation and wireless resource.Firstly it provides with a review of current investigations on computation and wireless resource management and an analysis of existing deficiencies and challenges.Then focusing on the provided challenges,the work proposes an MEC-based computation resource management scheme and a mixed numerology-based wireless resource management scheme.Furthermore,it outlines promising future technologies,including joint model-driven and data-driven resource management technology,and blockchain-based resource management technology within the 6G SIG network.The work also highlights remaining challenges,such as reducing communication costs associated with unstable ground-to-satellite links and overcoming barriers posed by spectrum isolation.Overall,this comprehensive approach aims to pave the way for efficient and effective resource management in future 6G networks. 展开更多
关键词 Space-integrated-ground Radio access network MEC-based computation resource management Mixed numerology-based wireless resource management
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Hierarchical detection and tracking for moving targets in underwater wireless sensor networks 被引量:1
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作者 Yudong Li Hongcheng Zhuang +2 位作者 Long Xu Shengquan Li Haibo Lu 《Digital Communications and Networks》 2025年第2期556-562,共7页
It is difficult to improve both energy consumption and detection accuracy simultaneously,and even to obtain the trade-off between them,when detecting and tracking moving targets,especially for Underwater Wireless Sens... It is difficult to improve both energy consumption and detection accuracy simultaneously,and even to obtain the trade-off between them,when detecting and tracking moving targets,especially for Underwater Wireless Sensor Networks(UWSNs).To this end,this paper investigates the relationship between the Degree of Target Change(DoTC)and the detection period,as well as the impact of individual nodes.A Hierarchical Detection and Tracking Approach(HDTA)is proposed.Firstly,the network detection period is determined according to DoTC,which reflects the variation of target motion.Secondly,during the network detection period,each detection node calculates its own node detection period based on the detection mutual information.Taking DoTC as pheromone,an ant colony algorithm is proposed to adaptively adjust the network detection period.The simulation results show that the proposed HDTA with the optimizations of network level and node level significantly improves the detection accuracy by 25%and the network energy consumption by 10%simultaneously,compared to the traditional adaptive period detection schemes. 展开更多
关键词 Underwater wireless sensor networks The degree of target change Mutual information PHEROMONE Adaptive period
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Dynamic Multi-Target Jamming Channel Allocation and Power Decision-Making in Wireless Communication Networks:A Multi-Agent Deep Reinforcement Learning Approach
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作者 Peng Xiang Xu Hua +4 位作者 Qi Zisen Wang Dan Zhang Yue Rao Ning Gu Wanyi 《China Communications》 2025年第5期71-91,共21页
This paper studies the problem of jamming decision-making for dynamic multiple communication links in wireless communication networks(WCNs).We propose a novel jamming channel allocation and power decision-making(JCAPD... This paper studies the problem of jamming decision-making for dynamic multiple communication links in wireless communication networks(WCNs).We propose a novel jamming channel allocation and power decision-making(JCAPD)approach based on multi-agent deep reinforcement learning(MADRL).In high-dynamic and multi-target aviation communication environments,the rapid changes in channels make it difficult for sensors to accurately capture instantaneous channel state information.This poses a challenge to make centralized jamming decisions with single-agent deep reinforcement learning(DRL)approaches.In response,we design a distributed multi-agent decision architecture(DMADA).We formulate multi-jammer resource allocation as a multiagent Markov decision process(MDP)and propose a fingerprint-based double deep Q-Network(FBDDQN)algorithm for solving it.Each jammer functions as an agent that interacts with the environment in this framework.Through the design of a reasonable reward and training mechanism,our approach enables jammers to achieve distributed cooperation,significantly improving the jamming success rate while considering jamming power cost,and reducing the transmission rate of links.Our experimental results show the FBDDQN algorithm is superior to the baseline methods. 展开更多
关键词 jamming resource allocation JCAPD MADRL wireless communication countermeasure wireless communication networks
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A Base Station Deployment Algorithm for Wireless Positioning Considering Dynamic Obstacles
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作者 Aiguo Li Yunfei Jia 《Computers, Materials & Continua》 2025年第3期4573-4591,共19页
In the context of security systems,adequate signal coverage is paramount for the communication between security personnel and the accurate positioning of personnel.Most studies focus on optimizing base station deploym... In the context of security systems,adequate signal coverage is paramount for the communication between security personnel and the accurate positioning of personnel.Most studies focus on optimizing base station deployment under the assumption of static obstacles,aiming to maximize the perception coverage of wireless RF(Radio Frequency)signals and reduce positioning blind spots.However,in practical security systems,obstacles are subject to change,necessitating the consideration of base station deployment in dynamic environments.Nevertheless,research in this area still needs to be conducted.This paper proposes a Dynamic Indoor Environment Beacon Deployment Algorithm(DIE-BDA)to address this problem.This algorithm considers the dynamic alterations in obstacle locations within the designated area.It determines the requisite number of base stations,the requisite time,and the area’s practical and overall signal coverage rates.The experimental results demonstrate that the algorithm can calculate the deployment strategy in 0.12 s following a change in obstacle positions.Experimental results show that the algorithm in this paper requires 0.12 s to compute the deployment strategy after the positions of obstacles change.With 13 base stations,it achieves an effective coverage rate of 93.5%and an overall coverage rate of 97.75%.The algorithm can rapidly compute a revised deployment strategy in response to changes in obstacle positions within security systems,thereby ensuring the efficacy of signal coverage. 展开更多
关键词 wireless positioning base station deployment dynamic obstacles dynamic obstacle wireless positioning
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Wireless Charger Capture for ElectroMagnetic Radiation Attack
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作者 Xue Gang Xu Jia +3 位作者 Jin Yong Wu Sixu Xu Lijie Luo Jian 《China Communications》 2025年第11期192-207,共16页
Wireless Power Transmission(WPT)has been widely used to replenish energy for various rechargeable devices.The ElectroMagnetic Radiation(EMR)of WPT has attracted great attention of safety concerns.It is possible for th... Wireless Power Transmission(WPT)has been widely used to replenish energy for various rechargeable devices.The ElectroMagnetic Radiation(EMR)of WPT has attracted great attention of safety concerns.It is possible for the malicious attacker to launch the EMR attack by capturing multiple wireless chargers.Little work has studied the EMR attack itself.In this paper,we propose a realistic EMR hazard model,which outputs the diminishing marginal hazard with EMR,with adjustable parameters to the target entities.We formulate three EMR attack models,termed Cumulative EMR Attack(CEA),Overall EMR Attack(OEA)and Unsafety EMR Attack(UEA),and propose the performance guaranteed algorithm of EMR attack for each model.We conduct extensive simulations and field experiments on a testbed.The results show that the proposed algorithms can output the near-optimal solution with much less running time than the optimal algorithms.The results of field experiments in a small testbed show that the utilities of CEAA and OEAA are increased by 70.5%and 12.9%than the comparison algorithms,respectively.Moreover,the number of captured chargers of UEAA is 5.9%less than the comparison algorithms.Our simulations also show the designed algorithms can perform better in a large-scale charging network. 展开更多
关键词 electromagnetic radiation submodular function wireless charger capture wireless power transmission
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Wireless Sensor Network Modeling and Analysis for Attack Detection
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作者 Tamara Zhukabayeva Vasily Desnitsky Assel Abdildayeva 《Computer Modeling in Engineering & Sciences》 2025年第8期2591-2625,共35页
Wireless Sensor Networks(WSN)have gained significant attention over recent years due to their extensive applications in various domains such as environmentalmonitoring,healthcare systems,industrial automation,and smar... Wireless Sensor Networks(WSN)have gained significant attention over recent years due to their extensive applications in various domains such as environmentalmonitoring,healthcare systems,industrial automation,and smart cities.However,such networks are inherently vulnerable to different types of attacks because they operate in open environments with limited resources and constrained communication capabilities.Thepaper addresses challenges related to modeling and analysis of wireless sensor networks and their susceptibility to attacks.Its objective is to create versatile modeling tools capable of detecting attacks against network devices and identifying anomalies caused either by legitimate user errors or malicious activities.A proposed integrated approach for data collection,preprocessing,and analysis in WSN outlines a series of steps applicable throughout both the design phase and operation stage.This ensures effective detection of attacks and anomalies within WSNs.An introduced attackmodel specifies potential types of unauthorized network layer attacks targeting network nodes,transmitted data,and services offered by the WSN.Furthermore,a graph-based analytical framework was designed to detect attacks by evaluating real-time events from network nodes and determining if an attack is underway.Additionally,a simulation model based on sequences of imperative rules defining behaviors of both regular and compromised nodes is presented.Overall,this technique was experimentally verified using a segment of a WSN embedded in a smart city infrastructure,simulating a wormhole attack.Results demonstrate the viability and practical significance of the technique for enhancing future information security measures.Validation tests confirmed high levels of accuracy and efficiency when applied specifically to detecting wormhole attacks targeting routing protocols in WSNs.Precision and recall rates averaged above the benchmark value of 0.95,thus validating the broad applicability of the proposed models across varied scenarios. 展开更多
关键词 wireless sensor network MODELING SECURITY ATTacK DETECTION MONITORING
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Mechanism of enhancing NH_(3)-SCR performance of Mn-Ce/AC catalyst by the structure regulation of activated carbon with calcite in coal
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作者 NIU Jian LI Yuhang +4 位作者 BAI Baofeng WEN Chaolu LI Linbo ZHANG Huirong GUO Shaoqing 《燃料化学学报(中英文)》 北大核心 2026年第1期69-79,共11页
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ... To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced. 展开更多
关键词 CALCITE activated carbon structure Mn-Ce/ac catalyst NH_(3)-SCR performance
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Review for wireless communication technology based on digital encoding metasurfaces
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作者 Haojie Zhan Manna Gu +10 位作者 Ying Tian Huizhen Feng Mingmin Zhu Haomiao Zhou Yongxing Jin Ying Tang Chenxia Li Bo Fang Zhi Hong Xufeng Jing Le Wang 《Opto-Electronic Advances》 2025年第7期51-106,共56页
Metasurfaces offer exceptional capabilities for controlling electromagnetic waves,enabling the realization of unique electromagnetic properties.As communication technology continues to evolve,metasurfaces present prom... Metasurfaces offer exceptional capabilities for controlling electromagnetic waves,enabling the realization of unique electromagnetic properties.As communication technology continues to evolve,metasurfaces present promising applications in wireless communications.This paper reviews the latest advancements in metasurface research within the communication sector,explores metasurface-based wireless relay technologies,and summarizes various wireless communication methods employing different types of metasurfaces across diverse modulation schemes.This paper provides a detailed discussion on the design of wireless communication systems based on coding metasurfaces to simplify transmitter architecture,as well as the development of intelligent coding metasurfaces in the communication field.It also elaborates on the application of vector vortex light fields in metasurface communication.Finally,it offers a forward-looking perspective on wireless communication systems that incorporate coded metasurfaces.This review aims to furnish researchers with a thorough understanding of the current state and future directions of coded metasurface applications in communications. 展开更多
关键词 coding metasurface RIS wireless communications signal modulation TRANSMITTER vortex light
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Demand side management with wireless channel impact in IoT-enabled smart grid system
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作者 Md.Farhad Hossain Kumudu S.Munasinghe +4 位作者 Nishant Jagannath Khandakar Tanvir Ahmed Md.Nabid Hasan Ibrahim Elgendi Abbas Jamalipour 《Digital Communications and Networks》 2025年第2期493-504,共12页
Demand Side Management(DSM)is a vital issue in smart grids,given the time-varying user demand for electricity and power generation cost over a day.On the other hand,wireless communications with ubiquitous connectivity... Demand Side Management(DSM)is a vital issue in smart grids,given the time-varying user demand for electricity and power generation cost over a day.On the other hand,wireless communications with ubiquitous connectivity and low latency have emerged as a suitable option for smart grid.The design of any DSM system using a wireless network must consider the wireless link impairments,which is missing in existing literature.In this paper,we propose a DSM system using a Real-Time Pricing(RTP)mechanism and a wireless Neighborhood Area Network(NAN)with data transfer uncertainty.A Zigbee-based Internet of Things(IoT)model is considered for the communication infrastructure of the NAN.A sample NAN employing XBee and Raspberry Pi modules is also implemented in real-world settings to evaluate its reliability in transferring smart grid data over a wireless link.The proposed DSM system determines the optimal price corresponding to the optimum system welfare based on the two-way wireless communications among users,decision-makers,and energy providers.A novel cost function is adopted to reduce the impact of changes in user numbers on electricity prices.Simulation results indicate that the proposed system benefits users and energy providers.Furthermore,experimental results demonstrate that the success rate of data transfer significantly varies over the implemented wireless NAN,which can substantially impact the performance of the proposed DSM system.Further simulations are then carried out to quantify and analyze the impact of wireless communications on the electricity price,user welfare,and provider welfare. 展开更多
关键词 Smart grid Real time pricing Demand side management wireless communications ZIGBEE
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由黏蛋白5AC探讨肺部炎症性疾病中的气道黏液高分泌
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作者 李明慧 吴铁军 《山东第一医科大学(山东省医学科学院)学报》 2026年第2期124-128,共5页
气道黏液高分泌广泛存在于肺部炎症性疾病中,并参与疾病的发生与进展。黏蛋白5AC(mucin 5AC,MUC5AC)是气道炎症反应过程中分泌的主要黏蛋白表型,是气道黏液高分泌的标志。本综述涉及气道黏蛋白的生理功能、病理变化、调控机制及对临床... 气道黏液高分泌广泛存在于肺部炎症性疾病中,并参与疾病的发生与进展。黏蛋白5AC(mucin 5AC,MUC5AC)是气道炎症反应过程中分泌的主要黏蛋白表型,是气道黏液高分泌的标志。本综述涉及气道黏蛋白的生理功能、病理变化、调控机制及对临床治疗的指导意义等多个方面,并系统阐述了气道黏蛋白的生理功能及炎症反应对黏蛋白表达的影响,将肺部炎症性疾病分为感染性与非感染性2种类型,分别对其中MUC5AC过度表达的调控机制及对疾病进程的影响进行总结归纳,总结了近十年的相关研究成果。通过探讨MUC5AC表达调控机制对肺部炎症性疾病临床治疗的启发与现有研究进展,以期为肺部炎症性疾病的治疗开拓思路。 展开更多
关键词 黏蛋白5ac 气道黏液高分泌 肺部炎症性疾病 调节机制
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大规模交直流混联电网中FACTS装置多目标鲁棒优化配置
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作者 谭荣昊 林舜江 梁炜焜 《电力系统保护与控制》 北大核心 2026年第3期144-155,共12页
为解决大规模交直流混联电网中输电断面的输电能力瓶颈问题,消纳送端更多的新能源出力,可通过在系统中合理配置可控串补(thyristor controlled series compensation,TCSC)和静止同步补偿器(static synchronous compensator,STATCOM)。... 为解决大规模交直流混联电网中输电断面的输电能力瓶颈问题,消纳送端更多的新能源出力,可通过在系统中合理配置可控串补(thyristor controlled series compensation,TCSC)和静止同步补偿器(static synchronous compensator,STATCOM)。基于此,考虑新能源出力的不确定性,以最小化年等值投资成本、最大化断面输电能力和新能源消纳容量作为优化目标,建立了大规模交直流混联电网中TCSC和STATCOM的多目标鲁棒优化配置模型。首先,采用凸松弛技术将原混合整数非线性规划模型转化为混合整数二阶锥约束规划模型,以提高模型求解的计算效率和所获得优化解的质量。然后,采用规格化法平面约束法将多目标鲁棒优化模型转化为一系列单目标鲁棒优化模型,再采用列与约束生成算法将单目标模型分解为主问题和子问题交替迭代求解,以得到在新能源场站最大可获得出力不确定波动的最恶劣情况下多目标优化模型的一系列Pareto最优解集,并采用熵权法确定出多目标折中最优解。最后,以修改的IEEE39节点系统和某实际大规模交直流电网为例进行计算,结果验证了所提模型和算法的有效性。 展开更多
关键词 柔性交流输电系统 交直流混联电网 多目标鲁棒优化 凸松弛
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Cost effective technologies for long range microwave wireless power transmission
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作者 CHOI Joon-Min KIM Dae-Kwan +3 位作者 PARK Durk-Jong YI Sang-Hwa KIM Dong-Min KO Dae-Ho 《中国空间科学技术(中英文)》 北大核心 2026年第1期122-134,共13页
Space-Based Solar Power(SBSP) presents a promising solution for achieving carbon neutrality and Renewable Electricity 100%(RE100) goals by offering a stable and continuous energy supply. However, its commercialization... Space-Based Solar Power(SBSP) presents a promising solution for achieving carbon neutrality and Renewable Electricity 100%(RE100) goals by offering a stable and continuous energy supply. However, its commercialization faces significant obstacles due to the technical challenges of long-distance microwave Wireless Power Transmission(WPT) from geostationary orbit. Even ground-based kilometer-scale WPT experiments remain difficult because of limited testing infrastructure, high costs, and strict electromagnetic wave regulations. Since the 1975 NASA-Raytheon experiment, which successfully recovered 30 kW of power over 1.55 km, there has been little progress in extending the transmission distance or increasing the retrieved power. This study proposes a cost-effective methodology for conducting long-range WPT experiments in constrained environments by utilizing existing infrastructure. A deep space antenna operating at 2.08 GHz with an output power of 2.3 kW and a gain of 55.3 dBi was used as the transmitter. Two test configurations were implemented: a 1.81 km ground-to-air test using an aerostat to elevate the receiver and a 1.82 km ground-to-ground test using a ladder truck positioned on a plateau. The rectenna consists of a lightweight 3×3 patch antenna array(0.9 m × 0.9 m), accompanied by a steering device and LED indicators to verify power reception. The aerostat-based test achieved a power density of 154.6 mW/m2, which corresponds to approximately 6.2% of the theoretical maximum. The performance gap is primarily attributed to near-field interference, detuning of the patch antenna, rectifier mismatch, and alignment issues. These limitations are expected to be mitigated through improved patch antenna fabrication, a transition from GaN to GaAs rectifiers optimized for lower input power, and the implementation of an automated alignment system. With these enhancements, the recovered power is expected to improve by approximately four to five times. The results demonstrate a practical and scalable framework for long-range WPT experiments under constrained conditions and provide key insights for advancing SBSP technology. 展开更多
关键词 wireless power transmission space-based solar power deep space antenna DSP KDSA KARI RECTENNA AEROSTAT
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基于分子对接技术筛选大菱鲆ACE抑制肽的研究
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作者 简恒源 赵彦钦 +10 位作者 陆佳伟 李燕苹 张瑶 张斌成 孔菲 王晓彤 代姣南 卢航 田元勇 鲁雪峰 赵慧 《农产品加工》 2026年第4期19-24,共6页
选择性筛选大菱鲆ACE抑制肽,利用生物信息学方法,以大菱鲆肌肉蛋白(ID:A0A8D3A461)为研究对象,在碱性蛋白酶(Subtilisin,EC 3.4.21.62)最适条件下对大菱鲆肌肉蛋白进行虚拟酶解,筛选具有ACE抑制活性的肽,并对其水溶性、毒性、等电点、... 选择性筛选大菱鲆ACE抑制肽,利用生物信息学方法,以大菱鲆肌肉蛋白(ID:A0A8D3A461)为研究对象,在碱性蛋白酶(Subtilisin,EC 3.4.21.62)最适条件下对大菱鲆肌肉蛋白进行虚拟酶解,筛选具有ACE抑制活性的肽,并对其水溶性、毒性、等电点、分子量及三维结构进行预测分析。虚拟酶解得到的肽段与ACE分子进行半柔性对接,筛选ACE抑制肽,选取其中3条潜在高活性ACE抑制肽(Arg-Phe,Arg-Phe,Gly-Trp),通过分子对接分析发现,上述活性肽与关键氨基酸(ARG522、GLU411)之间能够形成范德华力、电荷相互作用力、Pi-Pi键、盐桥等作用力,并可通过作用于Zn2+,改变ACE分子结构,进而通过竞争性ACE抑制作用达到降低血压的效果。虚拟筛选出的Arg-Phe和Arg-Phe能够显著降低SHR的收缩压,说明ACE抑制肽Arg-Phe和Arg-Phe具有降血压活性。研究结果证明了计算机模拟技术应用于活性肽研发的可行性,为研发具有ACE抑制活性的食源性降血压活性成分提供了新思路。 展开更多
关键词 食源性acE抑制肽 大菱鲆 分子对接 活性肽 降血压
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MUC5AC、TNF-α、CysLTs在儿童支原体肺炎伴气道黏液栓中的表达水平及意义
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作者 周琴 何云 +1 位作者 万恩宇 熊燕 《西部医学》 2026年第2期278-283,共6页
目的探讨儿童肺炎支原体肺炎(MPP)伴气道黏液栓(BMP)形成患儿肺泡灌洗液中黏蛋白5AC(MUC5AC)、肿瘤坏死因子-α(TNF-α)、半胱氨酰白三烯(CysLTs)的表达水平及意义。方法收集2023年12月—2024年8月在川北医学院附属医院儿科住院的符合MP... 目的探讨儿童肺炎支原体肺炎(MPP)伴气道黏液栓(BMP)形成患儿肺泡灌洗液中黏蛋白5AC(MUC5AC)、肿瘤坏死因子-α(TNF-α)、半胱氨酰白三烯(CysLTs)的表达水平及意义。方法收集2023年12月—2024年8月在川北医学院附属医院儿科住院的符合MPP诊断并进行电子支气管镜检查及肺泡灌洗治疗的儿童101例,根据电子支气管镜下是否观察到黏液栓堵塞气道分为BMP组(34例)和非BMP组(67例),收集两组临床资料及实验室数据进行比较。结果黏液栓组的住院时间、热程、肺实变及胸腔积液例数、中性粒细胞百分比(N%)、中性粒细胞与淋巴细胞比值(NLR)、C反应蛋白(CRP)、降钙素原(PCT)、肌酸激酶(CK)、乳酸脱氢酶(LDH)、纤维蛋白原(FIB)、MUC5AC、TNF-α均高于非黏液栓组,淋巴细胞百分比(L%)、白蛋白(Alb)、前白蛋白(PA)低于非黏液栓组,差异有统计学意义(均P<0.05),两组CysLTs相比,差异无统计学意义(P>0.05)。其中,MUC5AC、TNF-α、住院天数、肺实变是MPP伴BMP的独立危险因素。以MUC5AC、TNF-α水平绘制ROC曲线,预测MPP伴BMP的曲线下面积分别为0.835、0.810。MUC5AC与TNF-α水平呈正相关(r_(s)=0.402,P<0.0001)。结论MUC5AC、TNF-α在儿童MPP伴BMP中表达水平增高,对儿童黏液栓形成有预测价值。 展开更多
关键词 儿童 肺炎支原体肺炎 气道黏液栓 黏蛋白5ac 肿瘤坏死因子α 半胱氨酰白三烯
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The intelligent leap of wireless short-range connection
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作者 Wan Lei 《China Standardization》 2026年第1期47-47,共1页
Founded in September 2020,the International SparkLink Alliance(iSLA)now has approximately 1,200 members in diverse sectors including terminals,homes,vehicles,manufacturing,transportation,finance and healthcare.The iSL... Founded in September 2020,the International SparkLink Alliance(iSLA)now has approximately 1,200 members in diverse sectors including terminals,homes,vehicles,manufacturing,transportation,finance and healthcare.The iSLA has established a technical standards system for wireless short-range communication covering full-stack standards such as the end-to-end protocol system. 展开更多
关键词 wireless short range communication end end protocol system technical standards system full stack standards international sparklink alliance isla now wireless short range connection standards system ISLA
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Class-incremental open-set radio-frequency fingerprints identification based on prototypes extraction and self-attention transformation
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作者 XIE Cunxiang ZHONG Zhaogen ZHANG Limin 《Journal of Systems Engineering and Electronics》 2026年第1期112-126,共15页
In wireless sensor networks,ensuring communication security via specific emitter identification(SEI)is crucial.However,existing SEI methods are limited to closed-set scenarios and lack the ability to detect unknown de... In wireless sensor networks,ensuring communication security via specific emitter identification(SEI)is crucial.However,existing SEI methods are limited to closed-set scenarios and lack the ability to detect unknown devices and perform classincremental training.This study proposes a class-incremental open-set SEI approach.The open-set SEI model calculates radiofrequency fingerprints(RFFs)prototypes for known signals and employs a self-attention mechanism to enhance their discriminability.Detection thresholds are set through Gaussian fitting for each class.For class-incremental learning,the algorithm freezes the parameters of the previously trained model to initialize the new model.It designs specific losses:the RFFs extraction distribution difference loss and the prototype transformation distribution difference loss,which force the new model to retain old knowledge while learning new knowledge.The training loss enables learning of new class RFFs.Experimental results demonstrate that the open-set SEI model achieves state-of-theart performance and strong noise robustness.Moreover,the class-incremental learning algorithm effectively enables the model to retain old device RFFs knowledge,acquire new device RFFs knowledge,and detect unknown devices simultaneously. 展开更多
关键词 wireless sensor network specific emitter identification open-set identification class-incremental learning
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GMDSS中高频岸台自动连接系统(ACS)的技术研究与产品应用
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作者 钱志勇 郝源春 +2 位作者 吴益斌 顾康怡 曹永涛 《机电信息》 2026年第4期13-17,共5页
通过对GMDSS中自动连接系统(ACS)的技术标准、工作流程的技术研究,对国际标准进行了自主转化,针对性开发了ACS国产化岸台和船台通信系统和产品,并通过试验验证了系统的有效性。
关键词 中高频 海上通信 自动连接系统 acS
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