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Study of the EAST Fast Control Power Supply Based on Carrier Phase-Shift PWM
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作者 刘辉 唐柯 +3 位作者 高格 傅鹏 黄海宏 董琳 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第9期950-954,共5页
EAST (experimental advanced superconducting tokamak) fast control power supply is a high-capacity single-phase AC/DC/AC inverter power supply, which traces the displacement signal of plasma, and excites coils in a v... EAST (experimental advanced superconducting tokamak) fast control power supply is a high-capacity single-phase AC/DC/AC inverter power supply, which traces the displacement signal of plasma, and excites coils in a vacuum vessel to produce a magnetic field that realizes plasma stabilization. To meet the requirements of a large current and fast response, the multi- ple structure of the carrier phase-shift three-level inverter is presented, which realizes parallelled multi-inverters, raises the equivalent switching frequency of the inverters and improves the per- formance of output waves. In this work the design scheme is analyzed, and the output harmonic characteristic of parallel inverters is studied. The simulation and experimental results confirm that the scheme and control strategy is valid. The power supply system can supply a large current, and has a perfect performance on harmonic features as well as the ability of a fast response. 展开更多
关键词 EAST fast control power supply carrier phase-shift PWM
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Research on the Intelligent Control Strategy of the Fuel Cell Phase-Shifting Full-Bridge Power Electronics DC-DC Converter
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作者 Lei Zhang Yinlong Yuan +3 位作者 Yihe Sun Yun Cheng Dian Wu Lei Ren 《Energy Engineering》 EI 2022年第1期387-405,共19页
focus of all countries.As an effective new energy,the fuel cell has attracted the attention of scholars.However,due to the particularity of proton exchange membrane fuel cell(PEMFC),the performance of traditional PI c... focus of all countries.As an effective new energy,the fuel cell has attracted the attention of scholars.However,due to the particularity of proton exchange membrane fuel cell(PEMFC),the performance of traditional PI controlled phase-shifted full-bridge power electronics DC-DC converter cannot meet the needs of practical application.In order to further improve the dynamic performance of the converter,this paper first introduces several main topologies of the current mainstream front-end DC-DC converter,and analyzes their performance in the fuel cell system.Then,the operation process of the phase-shifted fullbridge power electronics DC-DC converter is introduced,and the shortcomings of the traditional PI control are analyzed.Finally,a double closed-loop adaptive fuzzy PI controller is proposed,which is characterized by dynamically adjusting PI parameters according to different working states to complete the intelligent control of phase-shifted full-bridge DC-DC converter.The simulation results in MATLAB/Simulink show that the proposed algorithm has good a control effect.Compared with the traditional algorithm,the overshoot and stabilization time of the system are shorter.The algorithm can effectively suppress the fluctuation of the output current of the fuel cell converter,and is a very practical control method. 展开更多
关键词 phase-shifted full-bridge adaptive fuzzy PI control proton exchange membrane fuel cell MATLAB/SIMULINK
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Guidance and Control Techniques of Carrier-Based Aircraft for Automatic Carrier Landing 被引量:9
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作者 Zhen Ziyang Zhang Zhibin Zhang Junhong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第6期600-608,共9页
We summarize the guidance and control techniques of automatic carrier landing for carrier-based aircraft.First,we analyze the carrier landing operations of the manned fixed-wing aircraft,unmanned fixed-wing aircraft a... We summarize the guidance and control techniques of automatic carrier landing for carrier-based aircraft.First,we analyze the carrier landing operations of the manned fixed-wing aircraft,unmanned fixed-wing aircraft and helicopters.Second,we look into the navigation and guidance system and the flight control methods for current different aircraft.Finally,we draw several conclusions of the development prospects for aircraft carrier landing,including the precision landing control techniques,precision approach and landing guidance techniques,and adaptive,reconfigurable and intelligent flight control techniques. 展开更多
关键词 carrier-based aircraft automatic carrier landing GUIDANCE flight control
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Automatic Carrier Landing Control for Unmanned Aerial Vehicles Based on Preview Control 被引量:9
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作者 Zhen Ziyang Ma Kun Bhatia Ajeet Kumar 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第4期413-419,共7页
For carrier-based unmanned aerial vehicles(UAVs),one of the important problems is the design of an automatic carrier landing system(ACLS)that would enable the UAVs to accomplish autolanding on the aircraft carrier.How... For carrier-based unmanned aerial vehicles(UAVs),one of the important problems is the design of an automatic carrier landing system(ACLS)that would enable the UAVs to accomplish autolanding on the aircraft carrier.However,due to the movements of the flight deck with six degree-of-freedom,the autolanding becomes sophisticated.To solve this problem,an accurate and effective ACLS is developed,which is composed of an optimal preview control based flight control system and a Kalman filter based deck motion predictor.The preview control fuses the future information of the reference glide slope to improve landing precision.The reference glide slope is normally a straight line.However,the deck motion will change the position of the ideal landing point,and tracking the ideal straight glide slope may cause landing failure.Therefore,the predictive deck motion information from the deck motion predictor is used to correct the reference glide slope,which decreases the dispersion around the desired landing point.Finally,simulations are carried out to verify the performance of the designed ACLS based on a nonlinear UAV model. 展开更多
关键词 carrier-based unmanned aerial vehicles optimal preview control automatic carrier landing system deck motion predictor
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H_∞ Preview Control for Automatic Carrier Landing 被引量:2
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作者 FARHAN Masood XUE Yixuan' +1 位作者 ZHEN Ziyang YANG Liuqing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第6期919-926,共8页
This paper focuses on the application of H_∞preview control in automatic carrier landing system(ACLS)for carrier-based aircraft.Due to the mutual movement between aircraft and carrier,the landing process becomes cons... This paper focuses on the application of H_∞preview control in automatic carrier landing system(ACLS)for carrier-based aircraft.Due to the mutual movement between aircraft and carrier,the landing process becomes considerably more challenging compared to a conventional runway landing.ACLS systems mitigate this by predicting deck motion and generating ideal glide slope path for tracking.Although,this predicted glide slope information is available in advance,conventional control structures are still unable to use this future information.H_∞preview control has the ability to utilize this future information for improving tracking response and disturbance rejection.The process of incorporating preview information into ACLS framework and synthesizing the H_∞preview controller is presented.The methodology is verified using the example of F/A-18 automatic carrier landing problem and results are presented. 展开更多
关键词 H∞control preview control carrierbased aircraft automatic carrier landing robust preview control
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Optimal Preview Control for Automatic Carrier Landing System of Carrier-Based Aircraft with Air Wake 被引量:1
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作者 Li Meng Zhen Ziyang +2 位作者 Gong Huajun Hou Min Huang Shuhong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第6期659-668,共10页
Carrier-based aircraft carrier landing is a special kind of tracking control problem and not suitable for classical control methods,which may miss the desired performance or result in overdesign.Therefore,we present a... Carrier-based aircraft carrier landing is a special kind of tracking control problem and not suitable for classical control methods,which may miss the desired performance or result in overdesign.Therefore,we present an optimal preview control for automatic carrier landing system(ACLS)by using state information of system,as well as future reference information,which can avoid the shortcomings of classical control methods.Since the flight performance of carrier-based aircraft is disturbed by air wake when the aircraft flies near the area of carrier stern,we design a disturbance rejection strategy to ensure that aircraft track the glide path with high precision and robustness.Further,carrier-based aircraft is a complex nonlinear system.However,the nonlinear model of carrier-based aircraft can be linearized at equilibrium landing state and decoupled into the longitudinal model and the lateral model.Therefore,an optimal preview control system is designed.The simulation results of a carrier-based aircraft show that the optimal preview control system can effectively suppress air wake.Tracking accuracy of optimal preview controller is higher than that of the proportional integral differential(PID)control system. 展开更多
关键词 carrier-based aircraft carrier landing optimal control preview control nonlinear model
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Optimal control based coordinated taxiing path planning and tracking for multiple carrier aircraft on flight deck 被引量:2
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作者 Xin-wei Wang Hai-jun Peng +3 位作者 Jie Liu Xian-zhou Dong Xu-dong Zhao Chen Lu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第2期238-248,共11页
Coordinated taxiing planning for multiple aircraft on flight deck is of vital importance which can dramatically improve the dispatching efficiency.In this paper,first,the coordinated taxiing path planning problem is t... Coordinated taxiing planning for multiple aircraft on flight deck is of vital importance which can dramatically improve the dispatching efficiency.In this paper,first,the coordinated taxiing path planning problem is transformed into a centralized optimal control problem where collision-free conditions and mechanical limits are considered.Since the formulated optimal control problem is of large state space and highly nonlinear,an efficient hierarchical initialization technique based on the Dubins-curve method is proposed.Then,a model predictive controller is designed to track the obtained reference trajectory in the presence of initial state error and external disturbances.Numerical experiments demonstrate that the proposed“offline planningþonline tracking”framework can achieve efficient and robust coordinated taxiing planning and tracking even in the presence of initial state error and continuous external disturbances. 展开更多
关键词 carrier aircraft Coordinated path planning Centralized optimal control Trajectory tracking Model predictive control
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Low Crosstalk Three-Color Infrared Detector by Controlling the Minority Carriers Type of InAs/GaSb Superlattices for Middle-Long and Very-Long Wavelength 被引量:5
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作者 蒋洞微 向伟 +7 位作者 国凤云 郝宏玥 韩玺 李晓超 王国伟 徐应强 于清江 牛智川 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第4期151-154,共4页
We report a type-Ⅱ InAs/GaSb superlattice three-color infrared detector for mid-wave (MW), long-wave (LW), and very long-wave (VLW) detections. The detector structure consists of three contacts of NIPIN archite... We report a type-Ⅱ InAs/GaSb superlattice three-color infrared detector for mid-wave (MW), long-wave (LW), and very long-wave (VLW) detections. The detector structure consists of three contacts of NIPIN architecture for MW and LW detections, and hetero-junction NIP architecture for VLW detection. It is found that the spectral crosstalks can be significantly reduced by controlling the minority carriers transport via doping beryllium in the two active regions of NIPIN section. The crosstalk detection at MW, LW, and VLW signals are achieved by selecting the bias voltages on the device. At 77K, the cutoff wavelengths of the three-color detection are 5.3μm (at OmV), 141μm (at 300mV) and 19μm (at -20mV) with the detectivities of 4.6xlO11 cm.Hzl/ZW-1, 2.3×10^10 cm.Hzl/2W-1, and 1.0×10^10cm.Hzl/2W-1 for MW, LW and VLW. The crosstalks of the MW channel, LW channel, and VLW channel are almost 0, 0.25, and 0.6, respectively. 展开更多
关键词 GaSb on of Low Crosstalk Three-Color Infrared Detector by controlling the Minority carriers Type of InAs/GaSb Superlattices for Middle-Long and Very-Long Wavelength by InAs for LONG
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Model-Free Adaptive Frequency Calibration for Voltage-Controlled Oscillators 被引量:1
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作者 Lianghui Xie Zhi Quan +1 位作者 Osama Elnaha Qinglin Zhao 《China Communications》 SCIE CSCD 2023年第1期199-208,共10页
The operating frequency accuracy of the local oscillators is critical for the overall system performance in the communication systems.However,the high-precision oscillators could be too expensive for civil application... The operating frequency accuracy of the local oscillators is critical for the overall system performance in the communication systems.However,the high-precision oscillators could be too expensive for civil applications.In this paper,we propose a model-free adaptive frequency calibration framework for a voltage-controlled crystal oscillator(VCO)equipped with a time to digital converter(TDC),which can significantly improve the frequency accuracy of the VCO thus calibrated.The idea is to utilize a high-precision TDC to directly measure the VCO period which is then passed to a model-free method for working frequency calibration.One advantage of this method is that the working frequency calibration employs the system history of input/output(I/O)data,instead of establishing an accurate VCO voltagecontrolled oscillator model.Another advantage is the lightweight calibration method with low complexity such that it can be implemented on an MCU with limited computation capabilities.Experimental results show that the proposed calibration method can improve the frequency accuracy of a VCO from±20 ppm to±10 ppb,which indicates the promise of the modelfree adaptive frequency calibrator for VCOs. 展开更多
关键词 frequency calibration carrier frequency offset MODEL-FREE adaptive control wireless communication systems
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The Research on Intelligent Controlled DDS of Polymer Carrier
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作者 ZHANG Zhi-bin LUO Juan +3 位作者 XU Cheng-yin CHEN Yuan-wei TANG Chang-wei WAN Chang-xiu 《合成化学》 CAS CSCD 2004年第z1期110-110,共1页
关键词 Intelligent polymer carrier DDS Intelligentlly controlled release.
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One step to generate quantum controlled phase-shift gate using a trapped ion
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作者 张世军 马驰 +1 位作者 张文海 叶柳 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1593-1596,共4页
This paper presents a very simple scheme for generating quantum controlled phase-shift gate with only one step by using the two vibrational modes of a trapped ion as the two qubits. The scheme couples two vibration de... This paper presents a very simple scheme for generating quantum controlled phase-shift gate with only one step by using the two vibrational modes of a trapped ion as the two qubits. The scheme couples two vibration degrees of freedom coupled with a suitable chosen laser excitation via the ionic states. 展开更多
关键词 one step controlled phase-shift gate trapped ion
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A Sensor-less Surface Mounted PMSM for Electronic Speed Control in Multilevel Inverter
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作者 S.Dinesh Kumar A.Jagadeeshwaran 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期2201-2215,共15页
Recent advancements in power electronics technology evolves inverter fed electric motors.Speed signals and rotor position are essential for controlling an electric motor accurately.In this paper,the sensorless speed c... Recent advancements in power electronics technology evolves inverter fed electric motors.Speed signals and rotor position are essential for controlling an electric motor accurately.In this paper,the sensorless speed control of surface-mounted permanent magnet synchronous motor(SPMSM)has been attempted.SPMSM wants a digital inverter for its precise working.Hence,this study incor-poratesfifteen level inverter to the SPMSM.A sliding mode observer(SMO)based sensorless speed control scheme is projected to determine rotor spot and speed of the multilevel inverter(MLI)fed SPMSM.MLI has been operated using a multi carrier pulse width modulation(MCPWM)strategy for generation offif-teen level voltages.The simulation works are executed with MATLAB/SIMU-LINK software.The steadiness and the heftiness of the projected model have been investigated under no loaded and loaded situations of SPMSM.Furthermore,the projected method can be adapted for electric vehicles. 展开更多
关键词 Surface-mounted permanent magnet synchronous motor sensorless speed control multilevel inverter torque estimation multi carrier pulse width modulation
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单相级联型多电平变换器直流纹波电压分析及抑制策略 被引量:1
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作者 陶海军 肖群星 +3 位作者 张金生 郑征 杨明 黄涛 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第1期113-123,共11页
级联H桥型多电平变换器采用移相变压器+整流供电时具有功率因数高、输出电压谐波含量低等优点,在大功率工业领域范围内得到了广泛应用。传统的调制算法都以假设直流母线电压恒定为前提,然而在直流侧会出现低频纹波并被调制和传输到负载... 级联H桥型多电平变换器采用移相变压器+整流供电时具有功率因数高、输出电压谐波含量低等优点,在大功率工业领域范围内得到了广泛应用。传统的调制算法都以假设直流母线电压恒定为前提,然而在直流侧会出现低频纹波并被调制和传输到负载,导致输出电压波形畸变。目的为了探讨级联H桥单元供电侧存在大量直流纹波电压导致输出负载电压波形畸变的问题,方法本文首先采用双重傅里叶理论分析直流纹波电压,在此基础上引入一种直流纹波前馈补偿策略,通过测量每个级联H桥的直流侧实际输入电压除以电压基准值并与传统载波信号相乘,进而与调制电压进行载波移相调制;同时采用矢量控制,通过FFT变换虚拟出无功电压,以获得更快的收敛速度、更高的稳定性和更小的振荡。结果仿真和实验结果表明,所提调制算法和控制策略可有效抑制负载电压中的低次谐波,减小输出电压波形畸变,实现逆变电源的快速动态响应和无稳态误差控制。结论实验结果验证了本文所采用的调制策略和控制策略的可行性与合理性。 展开更多
关键词 级联H桥 直流纹波 前馈补偿 载波移相调制 矢量控制
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不同海况条件下舰载无人机着舰安全分析
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作者 张子军 张山 王衍洋 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第1期136-143,共8页
针对无人机上舰的使用需求,本文对舰载无人机着舰开展了系统的研究。建立了机-舰-环境综合模型和舰载无人机全自动着舰引导控制系统;基于建立的舰载无人机着舰综合模型对不同海况下的着舰过程进行仿真分析,研究不同海况条件以及航母不... 针对无人机上舰的使用需求,本文对舰载无人机着舰开展了系统的研究。建立了机-舰-环境综合模型和舰载无人机全自动着舰引导控制系统;基于建立的舰载无人机着舰综合模型对不同海况下的着舰过程进行仿真分析,研究不同海况条件以及航母不同航速和遭遇角对着舰安全的影响。仿真研究表明:在复杂海况下,航母可通过适当提高航速以获得更高的着舰成功率,但过高的航速会导致舰尾流扰动加剧,使得着舰成功率显著下降;通过对仿真结果进行统计分析,给出了不同海况下的着舰安全范围,为无人机着舰辅助决策提供参考。 展开更多
关键词 舰载机 全自动着舰系统 安全分析 机舰适配性 着舰控制技术 无人机 航母 甲板运动
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基于PolM的微波光子线性优化链路
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作者 刘婷 陈博 +3 位作者 柳钰 薛小庆 郗艳华 张玉叶 《现代电子技术》 北大核心 2024年第11期1-5,共5页
文中提出一种利用偏振调制器(PolM)提高系统无杂散动态范围(SFDR)的方案,并进行了仿真验证。实现线性优化的原理是通过对微波光子链路中上下两路光载波进行完全抑制和部分抑制,使生成不同来源的三阶交调失真(IMD3)在电域实现自抵消。仿... 文中提出一种利用偏振调制器(PolM)提高系统无杂散动态范围(SFDR)的方案,并进行了仿真验证。实现线性优化的原理是通过对微波光子链路中上下两路光载波进行完全抑制和部分抑制,使生成不同来源的三阶交调失真(IMD3)在电域实现自抵消。仿真结果表明,IMD3的抑制比可达到61.9 dB,系统的三阶无杂散动态范围可达到107 dB·Hz^(2∕3)。该方案具有结构简单、实施难度低、大工作带宽和大动态范围的优势,在宽带无线通信、雷达、电子战系统中具有较大的应用潜力。 展开更多
关键词 微波光子 偏振调制器 无杂散动态范围 三阶交调失真 偏振控制器 光载波
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高速低载频比传感信号下的逆变器有源阻尼自适应控制
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作者 冯永芳 白娜 《传感技术学报》 CAS CSCD 北大核心 2024年第1期104-110,共7页
逆变器工作在高频运行和控制载波比低的情况下,存在谐振尖峰抑制,提出了高速低载频比传感信号下的逆变器有源阻尼自适应控制技术。在高速低载频比传感信号下,构建逆变器数学模型。输出电流到电容电压与定子电流之间的传递函数,将逆变器... 逆变器工作在高频运行和控制载波比低的情况下,存在谐振尖峰抑制,提出了高速低载频比传感信号下的逆变器有源阻尼自适应控制技术。在高速低载频比传感信号下,构建逆变器数学模型。输出电流到电容电压与定子电流之间的传递函数,将逆变器的有源阻尼等效成一个控制电压环。调整有源阻尼自适应控制回路的参数,制定逆变器有源阻尼自适应控制策略。实验结果表明:文中技术的稳定裕度由2.46 dB下降至1.18 dB,可以保证逆变器的稳定运行;在不同采样频率下,可以控制逆变器输出与电网电压相同相位和频率的并网电流,其中在采样频率为5.9f时,输出并网电流和电压均表现为正弦状态,波动范围分别为[35 A,58 A]和[185 V,225 V],具有较好的控制效果。 展开更多
关键词 传感信号 高速低载频比 有源阻尼控制 数学模型 逆变器
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基于电力载波与云计算的视频监控系统设计
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作者 罗启平 《科技创新与应用》 2024年第31期126-129,共4页
针对目前视频监控系统不断升级改造存在的布线工作量大、布线成本高、无法存储及计算海量视频文件的问题,该文提出基于电力载波技术和云计算框架的视频监控系统。视频数据经过调制解调、振荡、放大、耦合等过程,利用电力线网络传输到各... 针对目前视频监控系统不断升级改造存在的布线工作量大、布线成本高、无法存储及计算海量视频文件的问题,该文提出基于电力载波技术和云计算框架的视频监控系统。视频数据经过调制解调、振荡、放大、耦合等过程,利用电力线网络传输到各分控点,通过互联网传送到云端,利用云端强大的存储、计算能对视频数据进行各种处理。设计中硬件部分的ARM11微处理器主要负责视频数据的采集、编码并封包传送到PLC调制解调模块,完成数据收发控制和系统任务调度。软件部分主要包括开发系统搭建、USB摄像头驱动、视频数据采集、LCD实时显示、网络传输和双核数据处理等。该文的设计充分结合电力载波和云计算的特点,在视频监控领域中具有较高的应用价值。 展开更多
关键词 电力载波 云计算 视频监控 数据收发控制 系统任务调度
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室内VLC-WiFi异构网络中多色载波资源分配
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作者 陈勇 张薇薇 +1 位作者 刘焕淋 陈金林 《聊城大学学报(自然科学版)》 2024年第5期48-59,共12页
可见光通信接入点(VLC AP)在室内密集部署的方式在扩大VLC-WiFi系统容量的同时,增加了覆盖的小区间干扰。为了降低小区间干扰,提高系统的吞吐量和平均用户满意度,本文设计了多色载波分配与功率控制(MCAPC)的资源分配方法。该方法依据VLC... 可见光通信接入点(VLC AP)在室内密集部署的方式在扩大VLC-WiFi系统容量的同时,增加了覆盖的小区间干扰。为了降低小区间干扰,提高系统的吞吐量和平均用户满意度,本文设计了多色载波分配与功率控制(MCAPC)的资源分配方法。该方法依据VLC AP的部署位置和信道特性,采用软频率复用方法确定各VLC AP的无干扰的主载波和多色副载波,并设计基于匹配博弈的载波和子频带分配算法为用户分配异构网络的频带资源;最后,设计基于功率控制效用值的干扰抑制的载波功率控制算法进一步抑制小区间干扰。研究结果表明,所提MCAPC方法能够提高室内多色VLC-WiFi异构网的系统吞吐量和用户的平均满意度。 展开更多
关键词 异构网络 小区间干扰 多色载波 功率控制 系统吞吐量
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功能化纳米农药载药系统研究进展 被引量:1
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作者 刘慧慧 申越 +5 位作者 李兴业 李柠君 王心悦 安长成 吴青君 王琰 《农药学学报》 CAS CSCD 北大核心 2024年第3期415-426,共12页
纳米材料因其粒径小、尺寸易调节、种类丰富以及良好的移动性等优势,作为有效载体,在农药载药系统及农业病虫害防治方面受到了广泛关注。纳米材料与技术在提升农药生物利用度、溶解性和缓控释特性等方面展现出巨大的潜力。本文总结了利... 纳米材料因其粒径小、尺寸易调节、种类丰富以及良好的移动性等优势,作为有效载体,在农药载药系统及农业病虫害防治方面受到了广泛关注。纳米材料与技术在提升农药生物利用度、溶解性和缓控释特性等方面展现出巨大的潜力。本文总结了利用纳米材料与技术开发具有功能化纳米农药载药系统的研究进展,系统综述了精准释放农药活性成分的智能响应型农药控释制剂、叶面亲和型、土壤用药型及农药双载体系等不同功能化纳米农药载药系统,概述了其在农药减量增效和精准施用方面的作用效果,并对功能化纳米农药载药系统的应用场景与产业化潜力进行了展望。 展开更多
关键词 纳米农药 纳米载药系统 控释 智能响应 双载体系
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机载多载频频控阵非均匀距离模糊杂波抑制方法 被引量:1
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作者 刘成 王华柯 +1 位作者 全英汇 廖桂生 《系统工程与电子技术》 EI CSCD 北大核心 2024年第2期459-469,共11页
机载雷达下视工作面临严重的地海杂波,雷达平台运动造成杂波多普勒频率严重扩散,将微弱目标完全淹没。空时自适应处理(space time adaptive processing,STAP)技术通过联合多天线脉冲的接收信号,能够有效地抑制杂波,实现运动目标检测。... 机载雷达下视工作面临严重的地海杂波,雷达平台运动造成杂波多普勒频率严重扩散,将微弱目标完全淹没。空时自适应处理(space time adaptive processing,STAP)技术通过联合多天线脉冲的接收信号,能够有效地抑制杂波,实现运动目标检测。对于非正侧视阵列高速平台雷达,杂波距离依赖和距离模糊严重制约着目标检测性能。基于多载频频控阵,通过发射一组载频不同的正交信号,在杂波回波中,获得新的发射维自由度,并根据不同模糊在发射维的差异分离各模糊区域。此外,通过进一步对分离后的近程进行杂波补偿,利用降维STAP实现杂波抑制。仿真结果验证了所提方法的有效性。 展开更多
关键词 空时自适应处理 距离模糊 多载频频控阵 非均匀杂波
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