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A single-mask dry-release process for fabrication of high aspect ratio SOI MEMS devices

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中国科学：技术科学英文版 2013年第2期56卷 387-391页

作者： yang zhenchuan WEI YuMin MAO Xu YAN GuiZhen National Key Laboratory of Science and Technology on Micro/Nano Fabrication Institute of MicroelectronicsPeking University

A single-mask dry-release process for fabrication of high aspect ratio SOI MEMS devices is presented,which takes advantage of the lag effect in silicon DRIE(deep reactive ion etching).The wide trenches and the releasing holes are etched to the buried oxide in the first-step DRIE whereas the narrow trenches are still connected due to the lag effect.After the buried oxide is removed by wet etching through the opened releasing holes and wide trenches,the narrow trenches are etched through by the second-step DRIE.Not only can the sticking problems be avoided,but also the footing effect during the DRIE can be partially suppressed.The feasibility of the proposed technique was verified by implementing a capacitive accelerometer.The scale factor and the non-linearity of the fabricated accelerometer were measured to be 63.4 mV/g and 0.1% with the measurement range of ±1 g,respectively.

关键词： MEMS器件制造过程 SOI 纵横比深反应离子刻蚀电容式加速度计掩模加速度传感器

MEMS gyroscope control system using a band-pass continuous-time sigma-delta modulator

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Science China(Information Sciences) 2013年第10期56卷 180-189页

作者： DING HaiTao yang zhenchuan WANG ZhanFei KRAFT Michael YAN GuiZhen National Key Laboratory of Science and Technology on Micro/Nano Fabrication Institute of MicroelectronicsPeking University School of Electronics and Computer Science University of Southampton

This paper presents a MEMS gyroscope control system of using a high-order band-pass continuoustime sigma-delta modulator.Compared with a low-pass discrete-time sigma-delta modulator based solution,the band-pass modulator can considerably decrease the sampling frequency;moreover,the continuous-time architecture has an obvious advantage on PCB prototyping and shorter lead time of the implementation in hardware.System level simulations using MATLAB/Simulink show the proposed sixth order sigma-delta modulator can achieve a high SNR of 100 dB for an angular rate input with an amplitude of 200/s and a frequency of32 Hz.A PCB circuit implementation is simulated using Orcad/PSpice to analyze the stability,and implemented in hardware.Measurement of the power spectral density of the output bitstream reveals a noise floor of90 dBV/Hz1/2.The prototype is tested on a rate table with an angular rate input,verifying that the principle of the approach of using an electro-mechanical band-pass sigma-delta modulator control system for a MEMS gyroscope.

关键词： band-pass continuous-time control system MEMS gyroscope sigma-delta modulator

Closed loop control design for the sense mode of micromachined vibratory gyroscopes

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中国科学：技术科学英文版 2013年第5期56卷 1112-1118页

作者： HE ChunHua ZHAO QianCheng LIU YuXian yang zhenchuan YAN GuiZhen National Key Laboratory of Science and Technology on Micro/Nano Fabrication Institute of MicroelectronicsPeking University

This paper presents a novel design method of force rebalance control for the sense mode of micromachined vibratory gyroscopes.Specific theoretical deductions are performed to identify a precise linear model of the open loop system of the sense mode,which is crucial for the PI controller design.The frequency responses obtained by experimental tests agree well with those calculated with the theoretical model,indicating the accuracy of the theoretical analyses.Experimental results demonstrate that the bandwidth of the closed loop is extended to 94.8 Hz from 2.3 Hz in the open loop and the quadrature signal is suppressed by about 64 dBV in the closed loop system.The overshoot and stable time in the step response of the closed loop system are measured to be about 15% and 35 ms,respectively.The mode-splitting gyroscope with the closed loop controlled sense mode achieves a scale factor of 41.0 mV/deg/s with nonlinearity of 0.09% and asymmetry of 1%,and a bias instability of 4.0 °/h with angle random walk of 0.171 deg/h1/2.

关键词：振动陀螺仪闭环系统控制设计微机械检测线性模型实验测试 PI控制器

A novel robust design method for the sense mode of a MEMS vibratory gyroscope based on fuzzy reliability and Taguchi design

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Science China(Technological Sciences) 2017年第2期60卷 317-324页

作者： HE ChunHua ZHAO QianCheng HUANG QinWen LIN LongTao yang zhenchuan ZHANG DaCheng YAN GuiZhen National Key Laboratory of Science and Technology on Micro/Nano Fabrication Institute of MicroelectronicsPeking University Science and Technology on Reliability Physics and Application of Electronic Component Laboratory No.5 Electronics Research Institute of the Ministry of Industry and Information Technology

This paper proposes a novel robust design method for the sense mode of a MEMS vibratory gyroscope based on fuzzy reliability and Taguchi design. The principles of fuzzy reliability and Taguchi design are both introduced and described in detail. Experimental results demonstrate that the signal to noise ratio of the robust design scheme is better than those of the other experimental schemes.Over the full temperature range from -40 to 80°C, the temperature sensitivities of phase margin, gain margin, sensitivity margin,the maximum amplitude of open loop system, bandwidth of closed loop system, and the performance function of the robust design system are all smaller than those of the original design system. Meanwhile, the temperature sensitivity of the bandwidth of the robust design system is improved to 126 from 1075 ppm/°C. Moreover, the bias drift over the full temperature range of the robust design system is improved to 61°/h from 179°/h.

关键词：模糊可靠性设计方法振动陀螺仪 MEMS 鲁棒温度灵敏度传感设计系统

苇状木霉3199菌株对黄瓜枯萎病的生物防治研究

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植物病理学报 2024年第2期54卷 429-435页

作者：冉林焦阳凌键杨宇红茆振川谢丙炎李彦中国农业科学院蔬菜花卉研究所蔬菜生物育种全国重点实验室北京100081

黄瓜枯萎病由黄瓜专化型尖镰孢菌(Fusarium oxysporum f.***.cucumerinum,Foc)侵染引起,是黄瓜生产中较难防治的一种土传病害,发病时多造成植株萎蔫枯死,可导致黄瓜大幅减产。本研究从美国农业研究菌种保藏中心(Agricultural Research Se... 详细信息

黄瓜枯萎病由黄瓜专化型尖镰孢菌(Fusarium oxysporum f.***.cucumerinum,Foc)侵染引起,是黄瓜生产中较难防治的一种土传病害,发病时多造成植株萎蔫枯死,可导致黄瓜大幅减产。本研究从美国农业研究菌种保藏中心(Agricultural Research Service Culture Collection,NRRL)获得了一株可产生抗菌肽的木霉菌株3199,经形态学和分子生物学鉴定确定为苇状木霉(Trichoderma arundinaceum)。平板对峙试验发现菌株3199对Foc抑制效果明显。盆栽试验表明菌株3199孢子悬浮液(浓度1×10^(8)个孢子·mL^(-1))灌根对黄瓜枯萎病的防效为51.3%。进一步对该菌株的抑菌活性物质进行分析,发现其发酵液乙酸乙酯提取物(12 mg·mL^(-1))可显著抑制Foc生长。结果表明,T.arundinaceum菌株3199可代谢产生抑制Foc的活性天然产物,在黄瓜枯萎病生物防治方面有较大应用潜力。

关键词：苇状木霉生物防治尖镰孢菌黄瓜专化型次级代谢产物

体匿性存无痕有味——谈“散曲”在戏曲唱词创作中的运用

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戏友 2024年第1期 15-17页

作者：梁镇川不详

钱钟书先生在《谈艺录》第六十九节里细辨了诗歌中情与理的关系之后说:“理之在诗,如水中盐、蜜中花,体匿性存,无痕有味,现相无相,立说无说,所谓冥合圆显者也。”将钱钟书先生的这段精辟论述,借用到散曲在戏曲唱词创作中的灵活运用,也... 详细信息

钱钟书先生在《谈艺录》第六十九节里细辨了诗歌中情与理的关系之后说:“理之在诗,如水中盐、蜜中花,体匿性存,无痕有味,现相无相,立说无说,所谓冥合圆显者也。”将钱钟书先生的这段精辟论述,借用到散曲在戏曲唱词创作中的灵活运用,也是非常贴切的。一从初中二年级《文学》课本中接触了明代散曲家王磐的《朝天子·咏喇叭》《朝天子·瓶杏为鼠所啮》,便迷上了元曲。

关键词：钱钟书先生《谈艺录》明代散曲家情与理王磐散曲《文学》元曲

A flexible, robust, and high ion-conducting solid electrolyte membranes enabled by interpenetrated network structure for all-solid-state lithium metal battery

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Journal of Energy Chemistry 2022年第5期31卷 603-611页

作者： zhenchuan Tian Dukjoon Kim School of Chemical Engineering Sungkyunkwan UniversitySuwon 16419Republic of Korea

Poly(vinyl alcohol)/poly(ethylene glycol)(PVA/PEG) semi-interpenetrating networks(s-IPN) were synthesized for the application of solid electrolyte membranes of lithium metal batteries. Thermal, mechanical and dimensional stability, lithium-ion conductivity, interfacial compatibility, and cell performance were evaluated to assure their application. As this s-IPN structure suppressed the crystallinity by formation of network structure, both the lithium-ion conductivity and mechanical strength were simultaneously enhanced. The PVA/PEG-3s-IPN showed the highest lithium-ion conductivity of 3.26 × 10^(-4)S cm^(-1)in a wide electrochemical window(5.8 V vs. Li/Li^(+)), maintaining the robust solid-state with the tensile strength beyond 16.2 MPa at room temperature. The synthesized solid electrolyte membranes exhibited quite high specific capacity over 122 m Ah g^(-1)at 0.1 C from Li|PVA/PEG-3s-IPN|LiFePO_(4) cell and the long-term stable lithium stripping/plating performance for 1000 cycles from Li symmetric cell.

关键词： Solid polymer electrolyte Lithium battery Semi-IPN Lithium-ion conductivity

高等数学教学中的课程思政实现路径及案例探析

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黄山学院学报 2024年第3期26卷 105-107页

作者：周甄川黄山学院数学与统计学院安徽黄山245041

高等数学教学中课程思政目标的实现对高校立德树人起着重要的作用。从高等数学教学的目标设计、教学过程、课堂氛围、数学建模及数学文化教育5个方面以案例的形式介绍高等数学课程思政目标的实现途径和方法,旨在为新时代高校课程思政融... 详细信息

高等数学教学中课程思政目标的实现对高校立德树人起着重要的作用。从高等数学教学的目标设计、教学过程、课堂氛围、数学建模及数学文化教育5个方面以案例的形式介绍高等数学课程思政目标的实现途径和方法,旨在为新时代高校课程思政融入课堂教学提供参考。

关键词：课程思政高等数学实现路径案例探析

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核技术知识图谱的构建研究

计算机与数字工程 2024年第3期52卷 722-728页

作者：刘洋石睿王镇川吴亚东四川轻化工大学自动化与信息工程学院宜宾644000 四川轻化工大学计算机科学与工程学院宜宾644000

论文提出一种核技术知识图谱的构建方法,解决核技术知识不成体系、获取渠道难的问题,为用户提供一种智能化和结构化获取方式。首先采用自顶向下与自底向上相结合的方法分别构建模式层与数据层,利用Protégé本体编辑工具实现核技术知识... 详细信息

论文提出一种核技术知识图谱的构建方法,解决核技术知识不成体系、获取渠道难的问题,为用户提供一种智能化和结构化获取方式。首先采用自顶向下与自底向上相结合的方法分别构建模式层与数据层,利用Protégé本体编辑工具实现核技术知识图谱模式层的构建。使用爬虫技术实现核技术半结构化数据的抽取。根据ME+R+BIESO标注方法对核技术非结构化数据进行标注,分别使用CRF、BI-LSTM和BI-LSTM-CRF模型的命名识别方法对标注数据进行实体抽取,并通过实验结果得到BI-LSTM-CRF模型在核技术知识数据上效果优于其他两个模型。然后,通过知识融合,处理重复和错误的数据,实现核技术知识图谱数据层的构建。其次,采用Neo4j图数据库存储知识,成功构建核技术领域知识图谱。

关键词：核技术知识知识图谱本体构建命名识别方法图数据库