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Assessment and Visualization of Ki67 Heterogeneity in Breast Cancers through Digital Image Analysis
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作者 Chien-Hui Wu Min-Hsiang Chang +1 位作者 Hsin-Hsiu Tsai Yi-Ting Peng 《Advances in Breast Cancer Research》 CAS 2024年第2期11-26,共16页
The Ki67 index (KI) is a standard clinical marker for tumor proliferation;however, its application is hindered by intratumoral heterogeneity. In this study, we used digital image analysis to comprehensively analyze Ki... The Ki67 index (KI) is a standard clinical marker for tumor proliferation;however, its application is hindered by intratumoral heterogeneity. In this study, we used digital image analysis to comprehensively analyze Ki67 heterogeneity and distribution patterns in breast carcinoma. Using Smart Pathology software, we digitized and analyzed 42 excised breast carcinoma Ki67 slides. Boxplots, histograms, and heat maps were generated to illustrate the KI distribution. We found that 30% of cases (13/42) exhibited discrepancies between global and hotspot KI when using a 14% KI threshold for classification. Patients with higher global or hotspot KI values displayed greater heterogenicity. Ki67 distribution patterns were categorized as randomly distributed (52%, 22/42), peripheral (43%, 18/42), and centered (5%, 2/42). Our sampling simulator indicated analyzing more than 10 high-power fields was typically required to accurately estimate global KI, with sampling size being correlated with heterogeneity. In conclusion, using digital image analysis in whole-slide images allows for comprehensive Ki67 profile assessment, shedding light on heterogeneity and distribution patterns. This spatial information can facilitate KI surveys of breast cancer and other malignancies. 展开更多
关键词 Ki67 Heterogeneity Breast Cancer Digital Image Analysis
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RV减速机关键件及整机固有模态分析 被引量:5
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作者 张红 张方 +1 位作者 蒋祺 余啸 《电子测量技术》 2018年第21期54-58,共5页
以RV-40E减速机为研究对象,基于振动模态分析的基础理论,运用有限元联合仿真与模态实验相结合的方法,对该减速机关键零部件及整机的振动模态进行分析,得到关键件及整机的固有特性。对比有限元模态仿真结果与实验得到的模态参数,发现两... 以RV-40E减速机为研究对象,基于振动模态分析的基础理论,运用有限元联合仿真与模态实验相结合的方法,对该减速机关键零部件及整机的振动模态进行分析,得到关键件及整机的固有特性。对比有限元模态仿真结果与实验得到的模态参数,发现两者之间的误差值均低于9%,进一步验证了有限元模态仿真的正确性。有限元仿真分析可以有效地减少产品的设计周期和研发成本,为更好的分析结构的动力学性能、提高RV减速机的工作性能和疲劳寿命提供便捷有效的方法。 展开更多
关键词 减速机 有限元 模态仿真 模态实验
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RV减速机中曲柄轴与滚动轴承接触力有限元分析 被引量:2
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作者 张红 张方 +2 位作者 秦远田 蒋祺 余啸 《国外电子测量技术》 2018年第6期22-25,共4页
基于赫兹接触理论,并结合有限元接触分析的方法,以RV减速机为研究对象,在考虑减速机实际工作时的运动特征下,利用SolidWorks、ADAMS、MSC.Patran及Nastran构成有限元联合仿真平台,针对RV减速机主要传动零部件进行动力学仿真分析,验证了... 基于赫兹接触理论,并结合有限元接触分析的方法,以RV减速机为研究对象,在考虑减速机实际工作时的运动特征下,利用SolidWorks、ADAMS、MSC.Patran及Nastran构成有限元联合仿真平台,针对RV减速机主要传动零部件进行动力学仿真分析,验证了虚拟样机建构模型的正确性及减速机工作时的运动规律。并且根据动力学的仿真计算结果,对曲柄轴及滚动轴承进行静力学仿真计算,得到了曲柄轴与滚动轴承之间的接触力大小和分布规律,为更精确、更有效地研究RV减速机提供参考。 展开更多
关键词 减速机 曲柄轴 接触 有限元分析
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摆线针轮传动接触非线性疲劳寿命分析 被引量:1
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作者 张红 张方 +1 位作者 蒋祺 余啸 《国外电子测量技术》 2019年第1期11-14,共4页
基于摆线针轮传动啮合原理和赫兹接触理论,对RV减速器中摆线针轮啮合接触时的应力分布特点和最大啮合接触应力进行了理论分析和非线性有限元分析,对比两种方法得到的摆线针轮最大接触应力基本一致,均小于摆线针轮的齿面接触疲劳极限,验... 基于摆线针轮传动啮合原理和赫兹接触理论,对RV减速器中摆线针轮啮合接触时的应力分布特点和最大啮合接触应力进行了理论分析和非线性有限元分析,对比两种方法得到的摆线针轮最大接触应力基本一致,均小于摆线针轮的齿面接触疲劳极限,验证了该有限元模型的有效性和可参考性,为进一步的疲劳寿命预测和优化设计提供理论基础和有效数值分析方法。根据有限元静力分析结果,采用MSC.Patran对摆线针轮的疲劳寿命进行分析和预测。 展开更多
关键词 摆线针轮 接触 疲劳寿命
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海上风电场环形拓扑结构集电系统开关配置分析 被引量:5
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作者 陈献慧 王冰 +1 位作者 邓红峰 李伟 《可再生能源》 CAS 北大核心 2019年第2期205-211,共7页
为研究拓扑结构可靠性和成本对海上风电场集电系统的影响,文章以环形拓扑结构为例,根据开关配置方案分别建立风机、海缆和开关设备的可靠性评估模型和成本模型,通过实际海上风电场运行数据计算,对比最简单开关配置和完全开关配置的可靠... 为研究拓扑结构可靠性和成本对海上风电场集电系统的影响,文章以环形拓扑结构为例,根据开关配置方案分别建立风机、海缆和开关设备的可靠性评估模型和成本模型,通过实际海上风电场运行数据计算,对比最简单开关配置和完全开关配置的可靠性及成本差异。在此基础上,考虑未知个数开关设备,建立部分开关配置方案的可靠性模型及成本模型,利用NSGA-II算法实现可靠性及成本的Pareto最优,并设计出最优开关配置方案。 展开更多
关键词 环形拓扑 可靠性 部分开关配置 集电系统 海上风电场
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针摆减速器振动噪声特性仿真分析 被引量:3
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作者 李群超 张方 +1 位作者 蒋祺 彭学云 《国外电子测量技术》 2019年第1期106-111,共6页
未修形的标准摆线针轮在传动时易卡死,为补偿加工误差和保证润滑,需要对摆线盘齿廓修形。在保证相等的径向间隙和侧隙的条件下,提出了组合修形(正等距加负移距)和分段修形两种方式。基于赫兹接触理论并考虑接触变形,计算不同修形方式后... 未修形的标准摆线针轮在传动时易卡死,为补偿加工误差和保证润滑,需要对摆线盘齿廓修形。在保证相等的径向间隙和侧隙的条件下,提出了组合修形(正等距加负移距)和分段修形两种方式。基于赫兹接触理论并考虑接触变形,计算不同修形方式后针齿啮合力、啮合齿数、接触变形,并进行了三维实体建模、多刚体动力学仿真、有限元建模、强迫振动响应计算和声场分析,对比理论和仿真结果,验证Adams刚体动力学模型有效性,并得出分段修形在啮合力、振动噪声水平方面优于组合修形的结论。 展开更多
关键词 针摆 齿廓修形 啮合力 振动噪声 仿真
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区块链扩容技术研究综述 被引量:7
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作者 李洋 门进宝 +3 位作者 余晗 王思宁 范金刚 郭艳来 《电力信息与通信技术》 2020年第6期1-9,共9页
区块链优异的技术特性使其成为全球研究热点,但自身尚存在商用壁垒,尤其是系统性能不能满足当前数据大爆炸时代高频数据交互的实际需求,为此,学术界和产业界开展了区块链扩容技术研究,提出链下扩容、链上扩容和第0层扩容3类区块链扩容... 区块链优异的技术特性使其成为全球研究热点,但自身尚存在商用壁垒,尤其是系统性能不能满足当前数据大爆炸时代高频数据交互的实际需求,为此,学术界和产业界开展了区块链扩容技术研究,提出链下扩容、链上扩容和第0层扩容3类区块链扩容方案。文章通过梳理当下主流区块链扩容技术,对比分析各方案优劣,提出未来区块链扩容方案可能的实现方式。 展开更多
关键词 区块链技术 数据高频交互 性能扩展 扩容技术
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RV减速器单目标及多目标优化 被引量:2
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作者 朱梦 张方 +2 位作者 秦远田 蒋祺 郑美珠 《国外电子测量技术》 2017年第11期7-10,共4页
虽然RV减速器具有体积小、重量轻、传动平稳、寿命长、传动效率高等一系列优点,但是摆线盘和针齿啮合时的接触应力比较大,磨损情况严重。为了优化结构的接触特性以及质量,以针轮的分布圆半径、短幅系数、针齿半径、摆线盘厚度为优化变量... 虽然RV减速器具有体积小、重量轻、传动平稳、寿命长、传动效率高等一系列优点,但是摆线盘和针齿啮合时的接触应力比较大,磨损情况严重。为了优化结构的接触特性以及质量,以针轮的分布圆半径、短幅系数、针齿半径、摆线盘厚度为优化变量,分别以最大接触应力、质量最小化为优化目标,分别采用遗传算法和fmincon非线性优化方法进行优化。两种优化方法得到的结果比较一致,且都有比较明显的优化效果,但是造成另外一个优化目标的增大。为了使两个优化目标都得到比较良好的优化效果,采用fgoalattain多目标算法进行多目标优化。 展开更多
关键词 接触特性 质量 单目标优化 多目标优化
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异形螺母的开裂分析及试验验证 被引量:2
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作者 孙炳超 郑美珠 高军鹏 《热处理技术与装备》 2017年第4期50-52,共3页
针对异形螺母的开裂进行了分析,对该螺母开裂的疑似原因用相同材质的试样进行了验证,结果表明:与通油孔相同直径相同长度的内孔,在没有防渗措施的情况下,在与异形螺母同时生产时,能够被渗碳和淬硬,渗碳深度达1.2 mm;而在试样的内孔塞入... 针对异形螺母的开裂进行了分析,对该螺母开裂的疑似原因用相同材质的试样进行了验证,结果表明:与通油孔相同直径相同长度的内孔,在没有防渗措施的情况下,在与异形螺母同时生产时,能够被渗碳和淬硬,渗碳深度达1.2 mm;而在试样的内孔塞入硅酸铝纤维,且两端涂抹防渗剂的情况下,内孔没有被渗碳,防渗效果良好。据此,提出了改进措施。 展开更多
关键词 异形螺母 开裂 内孔 渗碳 防渗
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No Sustainability without Technical, Fiscal and Social Innovation
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作者 Schmidt-Bleek F Cheng Yiheng 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第3期9-15,共7页
Officially, the environmental protection from industrial insults began with Rachel Carson's book "The Silent Spring" in 1963. Protection priorities have since changed. They can be grouped into three successive phases.
关键词 中国 技术创新 社会变革 财政收入 环境保护 生物圈 疾病 臭氧层破坏
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Image Restoration Using Hybrid Features Improvement on Morphological Component Analysis
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作者 Der-Chang Tseng Ru-Yin Wei +1 位作者 Ching-Ta Lu Ling-Ling Wang 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第4期371-381,共11页
Images are generally corrupted by impulse noise during acquisition and transmission.Noise deteriorates the quality of images.To remove corruption noise,we propose a hybrid approach to restoring a random noisecorrupted... Images are generally corrupted by impulse noise during acquisition and transmission.Noise deteriorates the quality of images.To remove corruption noise,we propose a hybrid approach to restoring a random noisecorrupted image,including a block matching 3D(BM3D)method,an adaptive non-local mean(ANLM)scheme,and the K-singular value decomposition(K-SVD)algorithm.In the proposed method,we employ the morphological component analysis(MCA)to decompose an image into the texture,structure,and edge parts.Then,the BM3D method,ANLM scheme,and K-SVD algorithm are utilized to eliminate noise in the texture,structure,and edge parts of the image,respectively.Experimental results show that the proposed approach can effectively remove interference random noise in different parts;meanwhile,the deteriorated image is able to be reconstructed well. 展开更多
关键词 Adaptive non-local mean(ANLM) block matching 3D(BM3D) image restoration morphological component analysis(MCA) singular value decomposition(SVD).
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Towards a (More) Electronic Transmission and Distribution (eT&D)
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作者 Don Tan Damir Novosel 《CES Transactions on Electrical Machines and Systems》 2017年第1期15-25,共11页
The challenges and the path towards a(more)electronic transmission and distribution(eT&D)is presented in this paper.The challenges are first identified together with key stakeholders in the drive for grid moderniz... The challenges and the path towards a(more)electronic transmission and distribution(eT&D)is presented in this paper.The challenges are first identified together with key stakeholders in the drive for grid modernization.A fundamental question is then asked about the investment priority.Six basic characteristics are reviewed,leading to the composition of structured microgrids as the basic functional cell of a modern grid.One example of fractal radial structure and one fractal meshed structure are presented.The likely evolution path is then proposed together with basic technology sets.Specific foundation technologies are discussed in detail,including adiabatic power conversion,3MC technology,medium voltage conversion,distribution-level electronic power transformer and FACTs hardware integration,and back-to-back converters as a universal interconnect element.The rapidly emerging on-wire sensing technology is also discussed.It is pointed out that the distribution-level large electronic power transformer will provide a key component to enable hybrid ac/dc grid flow control and ancillary support for a flexible electronic transmission and distribution(eT&D)systems. 展开更多
关键词 All things grid connected electric power systems electronic transmission&distribution(eT&D) energy solutions flexible electronic transmission systems(FETS) grid modernization large electronic power transformers 3MC converters renewable energy.
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Analytical Verification of Performance of Deep Neural Network Based Time-synchronized Distribution System State Estimation
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作者 Behrouz Azimian Shiva Moshtagh +1 位作者 Anamitra Pal Shanshan Ma 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2024年第4期1126-1134,共9页
Recently,we demonstrated the success of a time-synchronized state estimator using deep neural networks(DNNs)for real-time unobservable distribution systems.In this paper,we provide analytical bounds on the performance... Recently,we demonstrated the success of a time-synchronized state estimator using deep neural networks(DNNs)for real-time unobservable distribution systems.In this paper,we provide analytical bounds on the performance of the state estimator as a function of perturbations in the input measurements.It has already been shown that evaluating performance based only on the test dataset might not effectively indicate the ability of a trained DNN to handle input perturbations.As such,we analytically verify the robustness and trustworthiness of DNNs to input perturbations by treating them as mixed-integer linear programming(MILP)problems.The ability of batch normalization in addressing the scalability limitations of the MILP formulation is also highlighted.The framework is validated by performing time-synchronized distribution system state estimation for a modified IEEE 34-node system and a real-world large distribution system,both of which are incompletely observed by micro-phasor measurement units. 展开更多
关键词 Deep neural network(DNN) distribution system state estimation(DSSE) mixed-integer linear programming(MILP) ROBUSTNESS trustworthiness
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打破循环的最短路算法
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作者 本·布鲁贝克 史永堂(翻译) 孙建(翻译) 《环球科学》 2023年第7期66-71,共6页
如今,即使是一些路径存在阻力的情况下,研究人员也能够以接近理论极限的速度搜寻到节点网络中的最短路径。在生活中,负面情绪是一种消耗。与之相似的,在算法中,负数也是一种阻力。考虑这样一个问题:在由链接或边连接的节点网络(也称为图... 如今,即使是一些路径存在阻力的情况下,研究人员也能够以接近理论极限的速度搜寻到节点网络中的最短路径。在生活中,负面情绪是一种消耗。与之相似的,在算法中,负数也是一种阻力。考虑这样一个问题:在由链接或边连接的节点网络(也称为图)中,搜寻两点之间的最短路径。这实际上是图论研究中的一个经典算法问题,最短路问题。通常情况下,图中的边是不可互换的,因为它们之间可能存在差异,比如路径图中的一些边可以表示某些道路比其他道路速度更慢、或是比其他道路收费更高。 展开更多
关键词 最短路算法 路径图 最短路径 理论极限 道路收费 负面情绪 最短路问题 链接
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时间能“翻转”吗?
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作者 查理·伍德 赵剑琳(翻译) 《环球科学》 2023年第7期92-92,共1页
通过操纵光子的行为,能够让时间看上去像是同时在两个方向上流动。通过物理学家精心设计的量子电路,光子可以在时间同时向前和向后叠加的路径中流动。遗憾的是,这与科幻电影中的时空穿梭机器没有任何共同点,时钟始终稳定地沿顺指针方向... 通过操纵光子的行为,能够让时间看上去像是同时在两个方向上流动。通过物理学家精心设计的量子电路,光子可以在时间同时向前和向后叠加的路径中流动。遗憾的是,这与科幻电影中的时空穿梭机器没有任何共同点,时钟始终稳定地沿顺指针方向运转,只有实验电路中光子的时间箭头经历了诡异的翻转。这一令人费解的现象究竟是真实的还是模拟的还存在争议,但无论如何,它都可能激发新型量子技术的诞生。 展开更多
关键词 科幻电影 量子技术 实验电路 量子电路 翻转 光子
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Multigigawatt 50 fs Yb:CALGO regenerative amplifier system with 11 W average power and mid-infrared generation 被引量:1
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作者 WEIZHE WANG HAN WU +2 位作者 CHENG LIU BIAO SUN HOUKUN LIANG 《Photonics Research》 SCIE EI CAS CSCD 2021年第8期1439-1445,共7页
Lasers with high average and high peak power as well as ultrashort pulse width have been all along demanded by nonlinear optics studies,strong-field experiments,electron dynamics investigations,and ultrafast spectrosc... Lasers with high average and high peak power as well as ultrashort pulse width have been all along demanded by nonlinear optics studies,strong-field experiments,electron dynamics investigations,and ultrafast spectroscopy.While the routinely used titanium-doped sapphire(Ti:sapphire)laser faces a bottleneck in the average power upscaling,ytterbium(Yb)-doped lasers have remarkable advantages in achieving high average power.However,there is still a substantial gap of pulse width and peak power between the Ti:sapphire and Yb-doped lasers.Here we demonstrate a high-power Yb:CaAlGdO4(Yb:CALGO)regenerative amplifier system,delivering 1040 nm pulses with11 W average power,50 fs pulse width,and 3.7 GW peak power at a repetition rate of 43 k Hz,which to some extent bridges the gap between the Ti:sapphire and Yb lasers.An ultrabroadband Yb-doped fiber oscillator,specially designed spectral shapers,and Yb:CALGO gain medium with broad emission bandwidth,together with a double-end pumping scheme enable an amplified bandwidth of 19 nm and 95 fs output pulse width.To the best of our knowledge,this is the first demonstration of sub-100 fs regenerative amplifier based on Yb-doped bulk medium without nonlinear spectral broadening.The amplified pulse is further compressed to 50 fs via cascaded-quadratic compression with a simple setup,producing 3.7 GW peak power,which boosts the record of peak power from Yb:CALGO regenerative amplifiers by 1 order.As a proof of concept,pumped by the high-power,50 fs pulses,7.5–11.5μm midinfrared(MIR)generation via intrapulse difference-frequency generation is performed,without the necessity of nonlinear fiber compressors.It leads to a simple and robust apparatus,and it would find good usefulness in MIR spectroscopic applications. 展开更多
关键词 AMPLIFIER power PUMPED
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Technical cross-fertilization between terrestrial microgrids and ship power systems 被引量:3
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作者 Robert E.HEBNER Fabian M.URIARTE +17 位作者 Alexis KWASINSKI Angelo L.GATTOZZI Hunter B.ESTES Asif ANWAR Pietro CAIROLI Roger A.DOUGAL Xianyong FENG Hung-Ming CHOU Laurence J.THOMAS Manisa PIPATTANASOMPORN Saifur RAHMAN Farid KATIRAEI Michael STEURER M.Omar FARUQUE Mario A.RIOS Gustavo A.RAMOS Mirrasoul J.MOUSAVI Timothy J.MCCOY 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2016年第2期161-179,共19页
Aspects of terrestrial microgrids and ship power systems are examined.The work exposes a variety of technical synergies from these two power systems to effectively advance their technologies.Understanding their overla... Aspects of terrestrial microgrids and ship power systems are examined.The work exposes a variety of technical synergies from these two power systems to effectively advance their technologies.Understanding their overlap allows congruent efforts to target both systems;understanding their differences hinders conflict and redundancy in early-stage design.The paper concludes by highlighting how an understanding of both systems can reduce the investment in research resources. 展开更多
关键词 MICROGRID Power systems Ship power systems
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The Nonlinear Dynamic Behaviors of Electrostatic Micro-Tweezers
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作者 Bo-Wun Huang Chao-Jung Chen Jao-Hwa Kuang 《Communications in Computational Physics》 SCIE 2018年第6期253-267,共15页
This work addresses the nonlinear dynamic behavior of different electrostaticmicro-tweezers,amicro electric actuator.This actuator,a cantilever beamelectrostatic micro-tweezers,has been extensively used in micro-elect... This work addresses the nonlinear dynamic behavior of different electrostaticmicro-tweezers,amicro electric actuator.This actuator,a cantilever beamelectrostatic micro-tweezers,has been extensively used in micro-electro-mechanical systems(MEMS).The importance of micro electric actuators manufactured is higher than the other part of MEMS since it is the power source of the entire micro-electro-mechanical systems.In actual operation,the instability and bad dynamic characteristics of the electric actuators will cause larger displacement mobility error,such as transport behavior and response procedures failure,etc.,and even damage the micro-electro-mechanical systems.To improve the actuator dynamic displacement accuracy,the dynamic behavior in the electric actuator system must be studied,especially for nonlinear dynamic behavior of system.In this work,the differential quadrature method(DQM)was employed to solve the problem of nonlinearity in the equation of motion.The results reveal that the proposed DQM model can be used to simulate the nonlinear behavior of the micro-tweezers efficiently Micro-tweezers of various shapes were studied to examine the feasibility of applying the DQMin analyzing their nonlinear responses.The simulated results agree very closely with the calculated and experimental data in the literature. 展开更多
关键词 Microelectromechanical PULL-IN Differential Quadrature Method(DQM) MEMS ELECTROSTATIC micro-tweezers
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SUBHARMONIC RESONANCE IN PULSE FOURIER TRANSFORM NMR
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作者 叶朝辉 李丽云 +2 位作者 裘鑑卿 杨继春 吴皙莉 《Chinese Science Bulletin》 SCIE EI CAS 1985年第5期598-601,共4页
The multiple quantum process, in which n quanta of energy ω0/n are absorbed or emitted between a pair of adjacent levels spaced out by ω0, is called subharmonie resonance (SHR). There is no real intermediate level... The multiple quantum process, in which n quanta of energy ω0/n are absorbed or emitted between a pair of adjacent levels spaced out by ω0, is called subharmonie resonance (SHR). There is no real intermediate level between the level pair. The transition between the two levels is generally allowed and it is directly observable under the pulsed excitation. The excitation will be very inefficient since the irradiation frequency is far away from, the resonance, so to deal with it, a higher order perturbation is needed. 展开更多
关键词 IRRADIATION inefficient absorbed PERTURBATION EXCITATION emitted stronger OBSERVABLE allowed PULSED
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