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Fuzzy-Model-Based Finite Frequency Fault Detection Filtering Design for Two-Dimensional Nonlinear Systems
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作者 Meng Wang Huaicheng Yan +1 位作者 Jianbin Qiu Wenqiang Ji 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2099-2110,共12页
This article studies the fault detection filtering design problem for Roesser type two-dimensional(2-D)nonlinear systems described by uncertain 2-D Takagi-Sugeno(T-S)fuzzy models.Firstly,fuzzy Lyapunov functions are c... This article studies the fault detection filtering design problem for Roesser type two-dimensional(2-D)nonlinear systems described by uncertain 2-D Takagi-Sugeno(T-S)fuzzy models.Firstly,fuzzy Lyapunov functions are constructed and the 2-D Fourier transform is exploited,based on which a finite frequency fault detection filtering design method is proposed such that a residual signal is generated with robustness to external disturbances and sensitivity to faults.It has been shown that the utilization of available frequency spectrum information of faults and disturbances makes the proposed filtering design method more general and less conservative compared with a conventional nonfrequency based filtering design approach.Then,with the proposed evaluation function and its threshold,a novel mixed finite frequency H_(∞)/H_(-)fault detection algorithm is developed,based on which the fault can be immediately detected once the evaluation function exceeds the threshold.Finally,it is verified with simulation studies that the proposed method is effective and less conservative than conventional non-frequency and/or common Lyapunov function based filtering design methods. 展开更多
关键词 Fault diagnosis finite frequency specifications mixed H_(∞)/H_(-)performance two-dimensional nonlinear systems
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^(124)I的制备、抗体标记及标记化合物的Micro-PET/CT显像
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作者 侯兴国 王风 +2 位作者 丁缙 朱华 杨志 《同位素》 CAS 2024年第4期387-393,共7页
为使用医用回旋加速器生产^(124)I及研究^(124)I标记提供方法,本研究通过124Te(p,n)^(124)I核反应制备^(124)I,首先压制得到124TeO_(2)/Al_(2)O_(3)靶片,利用回旋加速器轰击3~8 h后,放置12 h去除副反应产生的杂质核素,最后通过碘升华-... 为使用医用回旋加速器生产^(124)I及研究^(124)I标记提供方法,本研究通过124Te(p,n)^(124)I核反应制备^(124)I,首先压制得到124TeO_(2)/Al_(2)O_(3)靶片,利用回旋加速器轰击3~8 h后,放置12 h去除副反应产生的杂质核素,最后通过碘升华-放化分离法得到Na^(124)I溶液。分析Na^(124)I的纯度并且标记抗间皮素(mesothelin,MSLN)抗体后,对KM小鼠进行尾静脉注射观察^(124)I-anti-MSLN的分布。结果显示,压制得到的124TeO_(2)/Al_(2)O_(3)靶片经过12.5 MeV能量,20μA质子束轰击后得到340.4~1121.1 MBq核素产品,经纯化后得274.2~758.5 MBq高纯度Na^(124)I溶液,其放射性浓度>54840 Bq/μL。使用该Na^(124)I溶液对抗MSLN抗体标记得到放化纯度>99%的^(124)I-anti-MSLN探针,经尾静脉注射入KM小鼠体内,通过Micro-PET/CT显像可以观察到小鼠甲状腺部位有明显的探针摄取,且该摄取可以被提前3 d喂食0.5%KI溶液阻断,代谢行为符合^(124)I标记的抗体探针在KM鼠体内的代谢规律。本研究总结了25次^(124)I的制备过程中涉及的设备、方法及纯化后Na^(124)I的使用等情况,结果表明,经过纯化得到的^(124)I具有较高的核纯度和化学纯度,满足放射性标记的需求,且平均回收率高于70%,自动纯化过程安全可靠。 展开更多
关键词 固体靶核素 -124 -124靶片 ^(124)I自动纯化系统 micro-PET/CT
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Research on hsa-miR-155-3p and hsa-miR-155-5p as biomarkers for systemic sclerosis and their role in regulating biological behavior
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作者 WANG Bao-yue SUN Xiao-lin WANG Yong-fu 《Journal of Hainan Medical University》 CAS 2024年第3期32-41,共10页
Objective: This study was to investigate the role of hsa-miR-155-3p and hsa-miR-155-5p as biomarkers and regulators of biological behavior in Systemic Sclerosis. Methods: A total of 10 SSc patients and 10 healthy cont... Objective: This study was to investigate the role of hsa-miR-155-3p and hsa-miR-155-5p as biomarkers and regulators of biological behavior in Systemic Sclerosis. Methods: A total of 10 SSc patients and 10 healthy controls were selected for the study. The expression levels of hsa-miR-155-3p and hsa-miR-155-5p in peripheral blood mononuclear cells of SSc patients and healthy controls were measured using RT-qPCR. The diagnostic value of these miRNAs was explored using Receiver Operating Characteristic curve analysis. Pearson or Spearman correlation analysis was performed to assess the correlation between miRNAs and clinical indicators in SSc patients. Potential target genes of hsa-miR-155-3p and hsa-miR-155-5p were predicted using miRDB, Targetscan, and miRDIP databases. GO functional annotation, KEGG pathway enrichment analysis, protein-protein interaction network construction, and selection of central genes were conducted. Results: The expression levels of hsa-miR-155-3p and hsa- miR-155-5p were significantly higher in PBMCs of SSc patients compared to healthy controls (P<0.001). The ROC curve analysis showed that hsa-miR-155-3p and hsa-miR-155-5p had a high diagnostic value for SSc (AUC=1, P<0.001). Correlation analysis revealed that hsa- miR-155-3p, hsa-miR-155-5p, and clinical indicators such as high-resolution CT, neutrophil percentage, lymphocyte percentage, and albumin to globulin ratio were correlated (P<0.05). The signaling pathways enriched with target genes of hsa-miR-155-3p and hsa-miR-155- 5p were closely associated with the occurrence and development of SSc fibrosis, immunity, and inflammation. Conclusions: hsa-miR-155-3p and hsa-miR-155-5p may be involved in regulating the occurrence and development of SSc fibrosis, immunity, and inflammation. They have the potential to serve as biomarkers for clinical diagnosis and treatment of SSc. 展开更多
关键词 miR-155-3p miR-155-5p systemic sclerosis CORRELATION BIOMARKER
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Design and Testing of Three Earthing Systems for Micro-Grid Protection during the Islanding Mode 被引量:2
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作者 Rashad M. Kamel Aymen Chaouachi Ken Nagasaka 《Smart Grid and Renewable Energy》 2010年第3期132-142,共11页
This paper presents and tests three earthing systems (TT, TN and IT) for Micro-Grid (MG) protection against various fault types when the MG transferred to the islanding mode. The main contribution of this work is incl... This paper presents and tests three earthing systems (TT, TN and IT) for Micro-Grid (MG) protection against various fault types when the MG transferred to the islanding mode. The main contribution of this work is including the models of all micro sources which interfaced to the MG by power electronic inverters. Inverters in turns are provided with current limiters and this also included with the inverter models to exactly simulate the real situation in the MG during fault times. Results proved that the most suitable earthing system for MG protection during the islanding mode is the TN earthing system. That system leads to a suitable amount of fault current sufficient to activate over current pro-tection relays. With using TN earthing system, touch voltages at the faulted bus and all other consumer’s buses are less than the safety limited values during islanding mode. For the two others earthing systems (TT and IT), fault currents are small and nearly equal to the over load currents which make over current protection relay can not differentiate between fault currents and overload currents. All models of micro sources, earthing systems, inverters and control schemes are built using Matlab?/Simulink? environment. 展开更多
关键词 micro Grid PROTECTION EARTHING systems Fault Current Touch Voltage micro Sources and INVERTERS
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Comparison the Performances of Three Earthing Systems for Micro-Grid Protection during the Grid Connected Mode 被引量:2
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作者 Rashad Mohammedeen Kamel Aymen Chaouachi Ken Nagasaka 《Smart Grid and Renewable Energy》 2011年第3期206-215,共10页
This paper presents, tests and compares three earthing systems (TT, TN and IT) for Micro-Grid (MG) protection against various fault types during the connected mode. The main contribution of this work is including the ... This paper presents, tests and compares three earthing systems (TT, TN and IT) for Micro-Grid (MG) protection against various fault types during the connected mode. The main contribution of this work is including the models of all the micro sources which interfaced to the MG by power electronic inverters. Inverters in turns are provided with current limiters and this also included in the inverter models to exactly simulate the real situation in the MG during fault times. Results proved that the most suitable earthing system for MG protection during the connecting mode is the TN earthing system. That system leads to a suitable amount of fault current sufficient to activate over current protection relays. With using TN system, Touch voltages at the faulted bus and all other consumer’s buses are less than the safety limited value if current limiter is included with the transformer of the main grid which connects MG. For the two others earthing systems (TT and IT), fault current is small and nearly equal to the over load current which make over current protection relay can not differentiate between fault current and overload current. All models of micro sources, earthing systems, inverters, main grid and control schemes are built using Matlab?/Simulink? environment. 展开更多
关键词 micro GRID PROTECTION EARTHING systems Fault Current Touch Voltage micro Sources and Inverters GRID Connecting MODE
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Autonomous Multi-Factor Energy Flows Controller (AmEFC): Enhancing Renewable Energy Management with Intelligent Control Systems Integration
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作者 Dimitrios Vezeris Maria Polyzoi +2 位作者 Georgios Kotakis Pagona Kleitsiotou Eleni Tsotsopoulou 《Energy and Power Engineering》 2023年第11期399-442,共44页
The transition to sustainable energy systems is one of the defining challenges of our time, necessitating innovations in how we generate, distribute, and manage electrical power. Micro-grids, as localized energy hubs,... The transition to sustainable energy systems is one of the defining challenges of our time, necessitating innovations in how we generate, distribute, and manage electrical power. Micro-grids, as localized energy hubs, have emerged as a promising solution to integrate renewable energy sources, ensure energy security, and improve system resilience. The Autonomous multi-factor Energy Flow Controller (AmEFC) introduced in this paper addresses this need by offering a scalable, adaptable, and resilient framework for energy management within an on-grid micro-grid context. The urgency for such a system is predicated on the increasing volatility and unpredictability in energy landscapes, including fluctuating renewable outputs and changing load demands. To tackle these challenges, the AmEFC prototype incorporates a novel hierarchical control structure that leverages Renewable Energy Sources (RES), such as photovoltaic systems, wind turbines, and hydro pumps, alongside a sophisticated Battery Management System (BMS). Its prime objective is to maintain an uninterrupted power supply to critical loads, efficiently balance energy surplus through hydraulic storage, and ensure robust interaction with the main grid. A comprehensive Simulink model is developed to validate the functionality of the AmEFC, simulating real-world conditions and dynamic interactions among the components. The model assesses the system’s reliability in consistently powering critical loads and its efficacy in managing surplus energy. The inclusion of advanced predictive algorithms enables the AmEFC to anticipate energy production and consumption trends, integrating weather forecasting and inter-controller communication to optimize energy flow within and across micro-grids. This study’s significance lies in its potential to facilitate the seamless incorporation of RES into existing power systems, thus propelling the energy sector towards a more sustainable, autonomous, and resilient future. The results underscore the potential of such a system to revolutionize energy management practices and highlight the importance of smart controller systems in the era of smart grids. 展开更多
关键词 micro-GRID Smart Grid Interconnection Hybrid Renewable system Energy Flow Controller Battery Management Hydro Pump Off-Grid Solutions Ioniki Autonomous
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Study and Implementation on Batteries Charging Method of Micro-Grid Photovoltaic Systems 被引量:1
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作者 Tiezhou Wu Qing Xiao +2 位作者 Linzhang Wu Jie Zhang Mingyue Wang 《Smart Grid and Renewable Energy》 2011年第4期324-329,共6页
In the micro-grid photovoltaic systems, the random changes of solar radiation enable lead-acid batteries to experience low SOC (State of Charge) or overcharged for periods of time if directly charged with such traditi... In the micro-grid photovoltaic systems, the random changes of solar radiation enable lead-acid batteries to experience low SOC (State of Charge) or overcharged for periods of time if directly charged with such traditional methods as decreased charging current, which will reduce lifetime of batteries. What’s more, it’s difficult to find a proper reduction coefficient in decreasing charging current. To adapt to the random changes of circumstance and avoid selecting the reduction coefficient, a new fast charging method named decreased charging current based on SOC is proposed to apply into micro-grid photovoltaic systems. It combines batteries’ SOC with the maximum charging voltage to determine the charging rate without strictly selecting reduction coefficient. By close-loop current control strategy and related scheme, the experiment proves the new method is feasible and verifies that, comparing with decreased charging current, the improved method make batteries’ SOC reach 100% in shorter time as well as the temperature of batteries raise more slowly. 展开更多
关键词 micro-GRID PHOTOVOLTAIC system DECREASED CHARGING Current Based On SOC CHARGING Rate Reduction COEFFICIENT
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A novel strategy of smart manipulation by micro-scale oscillatory networks of the reactionary zones for enhanced extreme thrust control of the next-generation solid propulsion systems
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作者 Alexander N.Lukin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第5期635-642,共8页
The main aim of this research is to get a better knowledge and understanding of the micro-scale oscillatory networks behavior in the solid propellants reactionary zones. Fundamental understanding of the micro-and nano... The main aim of this research is to get a better knowledge and understanding of the micro-scale oscillatory networks behavior in the solid propellants reactionary zones. Fundamental understanding of the micro-and nano-scale combustion mechanisms is essential to the development and further improvement of the next-generation technologies for extreme control of the solid propellant thrust. Both experiments and theory confirm that the micro-and nano-scale oscillatory networks excitation in the solid propellants reactionary zones is a rather universal phenomenon. In accordance with our concept,the micro-and nano-scale structures form both the fractal and self-organized wave patterns in the solid propellants reactionary zones. Control by the shape, the sizes and spacial orientation of the wave patterns allows manipulate by the energy exchange and release in the reactionary zones. A novel strategy for enhanced extreme thrust control in solid propulsion systems are based on manipulation by selforganization of the micro-and nano-scale oscillatory networks and self-organized patterns formation in the reactionary zones with use of the system of acoustic waves and electro-magnetic fields, generated by special kind of ring-shaped electric discharges along with resonance laser radiation. Application of special kind of the ring-shaped electric discharges demands the minimum expenses of energy and opens prospects for almost inertia-free control by combustion processes. Nano-sized additives will enhance self-organizing and self-synchronization of the micro-and nano-scale oscillatory networks on the nanometer scale. Suggested novel strategy opens the door for completely new ways for enhanced extreme thrust control of the solid propulsion systems. 展开更多
关键词 Solid propulsion systems EXTREME thrust control Reactionary ZONES micro-SCALE OSCILLATORY NETWORKS Self-organized wave patterns Energy-releasing areas
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原子力显微镜-扫描电子显微镜共定位表征系统的研发与应用
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作者 蔡蕊 万鹏 +2 位作者 徐强 吕天明 孙智广 《分析测试技术与仪器》 CAS 2024年第1期53-57,共5页
微纳加工过程中,常有样品需要进行聚焦离子束(FIB)溅射、切割,扫描电子显微镜(SEM)以及原子力显微镜(AFM)表征,而这三类仪器都需要将样品固定在样品台上才可测试,固定不佳会影响表征结果.但固定好的样品在不同仪器之间转移、拆卸、再固... 微纳加工过程中,常有样品需要进行聚焦离子束(FIB)溅射、切割,扫描电子显微镜(SEM)以及原子力显微镜(AFM)表征,而这三类仪器都需要将样品固定在样品台上才可测试,固定不佳会影响表征结果.但固定好的样品在不同仪器之间转移、拆卸、再固定的过程中极易受到破坏.基于以上问题,设计了AFM-SEM-FIB样品共定位系统,可实现样品在此三种仪器之间的无损转移及共定位,避免珍贵样品破坏及目标丢失,以及解决AFM扫描无法控制方向、迅速调整位点等问题.在微纳表征中有优异的表现,系统已被开发成产品并量产销售. 展开更多
关键词 共定位系统 原子力显微镜 扫描电子显微镜 聚焦离子束 微纳表征
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基于改进LSTM网络的无人机MEMS-IMU零偏在线标定方法
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作者 程向红 吴昕怡 +1 位作者 刘丰宇 钟志伟 《中国惯性技术学报》 EI CSCD 北大核心 2024年第3期213-218,共6页
针对在卫星信号拒止、视觉系统退化场景中无人机MEMS-IMU零偏无法准确估计并补偿导致导航误差迅速发散的问题,提出一种基于改进长短时记忆(LSTM)网络的零偏在线标定方法。首先,为解决MEMS-IMU零偏数据非线性强、传统循环时间网络训练效... 针对在卫星信号拒止、视觉系统退化场景中无人机MEMS-IMU零偏无法准确估计并补偿导致导航误差迅速发散的问题,提出一种基于改进长短时记忆(LSTM)网络的零偏在线标定方法。首先,为解决MEMS-IMU零偏数据非线性强、传统循环时间网络训练效果差的问题,设计序列到序列的LSTM神经网络结构,引入教师强迫机制,提高了网络特征学习能力。然后,在导航过程中使用训练后的网络对MEMS-IMU零偏在线标定,补偿后的IMU量测与视觉信息联合优化,保证了导航定位精度。实验结果表明,在纯惯性导航实验中,所提方法的绝对位置误差比传统LSTM方法减小了6.5%;在EUROC数据集下进行的视觉惯性组合导航实验中,所提方法的平均绝对位置误差比传统LSTM方法减小了15%。 展开更多
关键词 无人机导航定位 微惯性测量单元 在线标定 长短时记忆神经网络
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基于IQPSO-EKF的多传感器融合姿态测量方法研究
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作者 胡启国 王磊 +1 位作者 马鉴望 任渝荣 《机电工程》 CAS 北大核心 2024年第2期353-363,共11页
为解决自动化竖井掘进设备的定位调姿精度对竖井、孔桩挖掘效率与质量的影响,提出了一种基于改进量子粒子群(IQPSO)-扩展卡尔曼滤波(EKF)的姿态测量算法,以提高微机电系统(MEMS)传感器测量精度。首先,对MEMS传感器数据进行了预处理(除... 为解决自动化竖井掘进设备的定位调姿精度对竖井、孔桩挖掘效率与质量的影响,提出了一种基于改进量子粒子群(IQPSO)-扩展卡尔曼滤波(EKF)的姿态测量算法,以提高微机电系统(MEMS)传感器测量精度。首先,对MEMS传感器数据进行了预处理(除噪、滤波、校准等);然后,参考现有飞行器的坐标系,建立了姿态解算模型,通过姿态角数学模型及运动学分析,构建了EFK状态方程,针对EKF方法参数估计不准确的问题,以分段混沌映射优化初始种群,引入平均位置最优值来避免陷入局部最优的IQPSO-EFK算法,优化EKF的系统、测量噪声的协方差参数;最后,对改进算法和三组姿态误差估计进行了对比实验。研究结果表明:对比三种典型目标函数,IQPSO-EFK相较于普通粒子群算法(QPSO-EFK)具有更强的寻优能力与收敛精度;对比三组旋转速度姿态测量误差,基于IQPSO-EKF算法的姿态测量方法在测量误差时比真实测量误差减少了约86.3%,比扩展卡尔曼滤波减少了约68.7%,比普通粒子群算法减少了约28.2%,证明该算法有效地提高了MEMS传感器测量精度。 展开更多
关键词 竖井掘进 角度测量仪器 姿态测量 微机电系统传感器 多传感器融合 改进量子粒子群-扩展卡尔曼滤波
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超微型Micro-LED投影显示光学引擎设计 被引量:1
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作者 黎垚 江昊男 +7 位作者 周自平 董金沛 陈恩果 叶芸 徐胜 孙捷 严群 郭太良 《液晶与显示》 CAS CSCD 北大核心 2023年第7期910-918,共9页
随着微米级像素尺寸的微型自发光二极管(Micro-LED,μLED)的出现和发展,采用μLED作为光源和像源的超微型投影光学引擎成为了可能,其极大简化了传统投影显示光学引擎的结构。本文提出了一种基于μLED的超微型投影光学引擎,基于现有3.302... 随着微米级像素尺寸的微型自发光二极管(Micro-LED,μLED)的出现和发展,采用μLED作为光源和像源的超微型投影光学引擎成为了可能,其极大简化了传统投影显示光学引擎的结构。本文提出了一种基于μLED的超微型投影光学引擎,基于现有3.302 mm(0.13 in)的μLED显示芯片设计了高像质的微型投影镜头。针对μLED的光分布特性,优化μLED发散角度与微投影镜头的光瞳匹配,有效提升了μLED微投影光学系统的光能利用率。结果表明,所设计的μLED微投影显示光学引擎体积仅有18.35 mm^(3),投影镜头中心视场的MTF值在截止频率处超过0.57。该μLED微投影显示光学引擎较好地实现了系统体积与成像像质的均衡,未来在AR/VR等近眼显示设备上具有广泛的应用前景。 展开更多
关键词 micro-LED 近眼显示 微投影显示 光学设计 系统效率
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Micro LED车灯投影光学系统设计与优化
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作者 李香兰 金霞 +7 位作者 吕金光 郑凯丰 陈宇鹏 赵百轩 赵莹泽 秦余欣 王惟彪 梁静秋 《中国光学(中英文)》 EI CAS CSCD 北大核心 2024年第1期89-99,共11页
本文提出了一种基于Micro LED阵列的车灯投影方案,设计了以像素尺寸为80μm×80μm的200×150白光Micro LED阵列作为显示光源,视场角为16°×34°的车灯投影光学系统,并对物面倾斜角度和光学系统结构进行了优化。此... 本文提出了一种基于Micro LED阵列的车灯投影方案,设计了以像素尺寸为80μm×80μm的200×150白光Micro LED阵列作为显示光源,视场角为16°×34°的车灯投影光学系统,并对物面倾斜角度和光学系统结构进行了优化。此外,分别采用反向畸变处理方法和像素灰度调制方法用以解决车灯投影图像的梯形畸变和照度均匀性问题,并搭建了投影实验平台,对图像校正方法进行了验证。实验结果表明:校正后图像梯形畸变系数p1,p2分别从0.0932和0.3680下降至0.0835和0.0373,像面照度均匀性从83.2%提高到93.2%。本文通过对基于Micro LED的倾斜投影车灯光学系统进行优化设计及采用图像校正方法,实现了高光效、低畸变的车灯投影。 展开更多
关键词 车灯投影光学系统 光学设计 micro LED 照度均匀性 梯形畸变
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微纳米塑料在土壤-植物系统中的迁移机制及毒性效应研究进展
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作者 张鑫雨 罗庆 +4 位作者 方旭 吴慧秋 寇力月 张截流 冯良山 《生态毒理学报》 CAS CSCD 北大核心 2024年第2期140-147,共8页
微塑料是指粒径小于5 mm的塑料碎屑和颗粒,其中粒径小于100 nm为纳米塑料。微纳米塑料作为一种新型污染物,具有难以降解、容易发生积累和可长距离迁移等特点,进而对生态环境产生影响。但是,与其他环境中的微纳米塑料相比,人们对土壤环... 微塑料是指粒径小于5 mm的塑料碎屑和颗粒,其中粒径小于100 nm为纳米塑料。微纳米塑料作为一种新型污染物,具有难以降解、容易发生积累和可长距离迁移等特点,进而对生态环境产生影响。但是,与其他环境中的微纳米塑料相比,人们对土壤环境中的微纳米塑料的认识与了解还比较少。所以,本文详细阐明了微纳米塑料在土壤环境中的生物和非生物迁移过程与机制,系统总结了微纳米塑料从土壤到植物的转运过程,并探讨了微纳米塑料对植物种子萌发和根系发育产生的直接毒性效应,通过改变土壤理化性质和吸附重金属、有机污染物进而成为污染物传输载体而对植物产生的间接毒性作用。最后,提出了土壤-植物系统中微纳米塑料污染目前还需要进一步研究和处理的问题。本文可为土壤-植物系统中微纳米塑料污染的生态风险评估提供科学参考。 展开更多
关键词 微纳米塑料 土壤-植物系统 迁移 毒性效应
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Ball Tips of Micro/Nano Probing Systems:A Review 被引量:1
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作者 Ruijun LI Chen CHEN +4 位作者 Dandong LI Kuang-Chao FAN Zhenying CHENG Qiangxian HUANG Xueming DANG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期222-230,共9页
To satisfy the measuring demands for the micro components of the industry, micro/nano probing systems with various ball tips have been developed. However, most of them cannot be used to measure the real micro geometri... To satisfy the measuring demands for the micro components of the industry, micro/nano probing systems with various ball tips have been developed. However, most of them cannot be used to measure the real micro geometrical features high precisely because the parameters of the ball tips are not appropriate. The ball tips with a diameter of less than 100 μm, a sphericity and eccentricity of far less than 1 μm are required urgently. A review on the state-of-the-art of ball tips of micro/nano probing systems is presented. The material characteristics and geometric parameters of now available ball tips are introduced sepa- rately. The existing fabrication methods for the ball tips are demonstrated and summarized. The ball tips' future trends, which are smaller diameter, better sphericity and smaller eccentricity, are proposed in view of the practical requirements of high-precision measurement for micro geometrical features. Some challenges have to be faced in future, such as the promotion and high-precision measurement for the small ball tip's sphericity and eccentricity. Fusion method without the gravity effect when the molten ball tip solidifying is a more suitable way to fabricate a small diameter ball tip together with a shaft. 展开更多
关键词 Ball tip · Probe - micro/nano CMMs · microcomponents
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Characterization of ceramic coating on ZK60 magnesium alloy prepared in a dual electrolyte system by micro-arc oxidation 被引量:7
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作者 Ze-Xin Wang Wei-Gang Lv +1 位作者 Jing Chen Sheng Lu 《Rare Metals》 SCIE EI CAS CSCD 2013年第5期459-464,共6页
Micro-arc oxidation (MAO) process was cartied out in an optimized dual electrolyte system to fabricate a compact, smooth, and corrosion resistant coating on ZK60 Mg alloy. The microstructural characteristics of coat... Micro-arc oxidation (MAO) process was cartied out in an optimized dual electrolyte system to fabricate a compact, smooth, and corrosion resistant coating on ZK60 Mg alloy. The microstructural characteristics of coating were investigated by scanning electron microscopy (SEM) coupled with an energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). Test of mass loss was conducted at a 3.5 % NaCl solution to assess the resistance to corrosion. The bonding strength between the coating and ZK60 substrate was evaluated using scratch experiment. The results reveal that MgA1204 and MgO are the main phases of ceramic coating obtained in the dual electrolyte system. The corrosion rate of coating prepared in the optimized dual electrolyte is only 0.0061 g.m-2.h-1, which demonstrates excellent corrosion resistance. This is mainly due to the compact, uniform coating with high bonding strength. 展开更多
关键词 ZK60 magnesium alloys micro-arc oxidation CHARACTERIZATION Dual electrolyte system
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Fast filtering algorithm based on vibration systems and neural information exchange and its application to micro motion robot 被引量:4
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作者 高娃 查富生 +1 位作者 宋宝玉 李满天 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期159-169,共11页
This paper develops a fast filtering algorithm based on vibration systems theory and neural information exchange approach. The characters, including the derivation process and parameter analysis, are discussed and the... This paper develops a fast filtering algorithm based on vibration systems theory and neural information exchange approach. The characters, including the derivation process and parameter analysis, are discussed and the feasibility and the effectiveness are testified by the filtering performance compared with various filtering methods, such as the fast wavelet transform algorithm, the particle filtering method and our previously developed single degree of freedom vibration system filtering algorithm, according to simulation and practical approaches. Meanwhile, the comparisons indicate that a significant advantage of the proposed fast filtering algorithm is its extremely fast filtering speed with good filtering perfi^rmance. Further, the developed fast filtering algorithm is applied to the navigation and positioning system of the micro motion robot, which is a high real-time requirement for the signals preprocessing. Then, the preprocessing data is used to estimate the heading angle error and the attitude angle error of the micro motion robot. The estimation experiments illustrate the high practicality of the proposed fast filtering algorithm. 展开更多
关键词 fast filtering vibration system neural information exchange micro motion robot
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Tronics Microsystems公司年终净利润达到1300万欧元
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作者 王淑华 王玲 《微纳电子技术》 CAS 2008年第6期372-372,共1页
关键词 systems公司 市场 半导体公司 micro 生产线
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Design of a Monitoring System of Micro-Grid 被引量:3
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作者 Xiangyang Zhao Shiyang Liu 《Smart Grid and Renewable Energy》 2013年第2期198-201,共4页
This paper describes a micro-grid system and its monitoring system. This micro-grid system consists of generation systems, consumer electrical equipments, auxiliary equipments and the monitoring system. All the equipm... This paper describes a micro-grid system and its monitoring system. This micro-grid system consists of generation systems, consumer electrical equipments, auxiliary equipments and the monitoring system. All the equipments have 485 communication interfaces. In order to monitor and manage this micro-grid system, we built a monitoring system, which contains modular instrument system and industrial personal computer. In order to keep real time, we adopt some measures in software and hardware. We adopt LABVIEW and its program modules in software and adopt modular instrument system in hardware. Supporting by the software and hardware, the micro-grid system can be safe and stable. 展开更多
关键词 micro-GRID REAL TIME The MONITORING system COMMUNICATION
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考虑新能源出力不确定性的风-光-柴-储系统调度策略
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作者 张佳辉 张洪福 +3 位作者 牛玉广 王雨宸 黄嘉鑫 王孟桐 《电测与仪表》 北大核心 2024年第3期20-25,共6页
文章以风-光-柴-储系统为研究对象,为了研究新能源出力不确定性对该系统的影响,提出了一种新能源出力复合预测模型。为提高风-光-柴-储系统运行的经济性、环保性和安全性,提出了考虑新能源出力不确定性的风-光-柴-储系统调度模型,并采... 文章以风-光-柴-储系统为研究对象,为了研究新能源出力不确定性对该系统的影响,提出了一种新能源出力复合预测模型。为提高风-光-柴-储系统运行的经济性、环保性和安全性,提出了考虑新能源出力不确定性的风-光-柴-储系统调度模型,并采用了带有Monte Carlo模拟的遗传算法对模型进行求解。文章采用了负荷缺失率(load loss rate,LLR)和置信概率对系统的安全性进行评价,并分析了其对系统调度结果的影响。仿真结果表明,文中所提出的考虑新能源出力不确定性的风-光-柴-储系统调度模型,可以降低新能源出力不确定性对系统的影响,且该方法可以有效地平衡系统的经济性和安全性。 展开更多
关键词 新能源 微网 调度策略 机会约束规划 电力系统安全性 不确定性
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