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Experiment on a Double-Foot Stepping Piezoelectric Linear Motor

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第3期35卷 423-431页

作者： Sun Mengxin huang weiqing Wang Yin Lu Qian State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics School of Mechanical and Electric Engineering Guangzhou University Center for Precision Measurement Technologies and Instruments Huaqiao University

A novel double-foot piezoelectric linear motor is *** kinematic model of the motor under stepping motion is *** motor mainly consists of a stator with four piezoelectric stacks,a mover,a holding mechanism,and a preloading mechanism to achieve large stroke with high *** element simulations are carried out to analyze the motion characteristics of the motor.A prototype is fabricated and a serial experiments are conducted to validate the feasibility of the motor *** results indicate that the motor can move at a speed of 670.22μm/s with a driving frequency of 120 Hz and a voltage of 120 *** resolution of the proposed motor is 3.6μm while the resolution of the single-step motion is 0.1μm.

关键词： piezoelectric linear motor piezoelectric stack performance test

Ti_(3)C_(2)T_(x)-纳米纤维素复合气凝胶的制备及其电化学性能的研究

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化工新型材料 2024年第5期52卷 141-145,149页

作者：曹小凤黄卫青王利魁刘竞刘宏治姚伯龙合成与生物胶体教育部重点实验室江南大学化学与材料工程学院无锡214122

将纳米纤维素(CNF)与Ti_(3)C_(2)T_(x)MXene按不同的质量比制备气凝胶。结果表明:复合气凝胶形成了泡沫状的三维分层结构,MXene的层间距得以扩大,其中丰富的孔道加速了离子的传输,较大的比表面积为电化学反应提供了更多的活性位点。当... 详细信息

将纳米纤维素(CNF)与Ti_(3)C_(2)T_(x)MXene按不同的质量比制备气凝胶。结果表明:复合气凝胶形成了泡沫状的三维分层结构,MXene的层间距得以扩大,其中丰富的孔道加速了离子的传输,较大的比表面积为电化学反应提供了更多的活性位点。当纳米纤维素/MXene质量比为1∶5时,该N_(1)M_(5)气凝胶电极的电化学性能最佳。N_(1)M_(5)气凝胶电极在0.5A/g时,比电容为208F/g,当电流密度增加至10A/g时,显示出85.1%的高容量保留率。在5A/g下充/放电10000次后,容量保持率高达97.3%,循环性能优异。

关键词：超级电容器 Ti_(3)C_(2)T_(x) MXene 纳米纤维素气凝胶电化学性能

益气养心方治疗冠心病室性心律失常的疗效及其对心肌缺血的血液流变学指标、CXCL9水平的影响

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检验医学与临床 2024年第8期21卷 1046-1048,1053页

作者：黄卫清杜婷婷蔡洋江西中医药大学附属医院急诊综合科江西南昌330006 江西中医药大学附属医院急诊科江西南昌330006

目的观察益气养心方治疗冠心病室性心律失常的临床疗效及其对心肌缺血的血液流变学指标、CXC趋化因子配体9(CXCL9)水平的影响。方法选取2021年6月至2022年12月在该院治疗的70例冠心病室性心律失常患者作为研究对象,采用随机数字表法分... 详细信息

目的观察益气养心方治疗冠心病室性心律失常的临床疗效及其对心肌缺血的血液流变学指标、CXC趋化因子配体9(CXCL9)水平的影响。方法选取2021年6月至2022年12月在该院治疗的70例冠心病室性心律失常患者作为研究对象,采用随机数字表法分为对照组和观察组,每组35例。两组患者均实施常规对症治疗,对照组在常规对症治疗的基础上给予酒石酸美托洛尔片治疗,观察组在对照组的基础上给予益气养心方治疗,两组患者均连续治疗4个月。观察两组临床疗效、血液流变学指标水平、血清CXCL9水平及不良反应情况。结果观察组治疗后总有效率高于对照组(P<0.05);两组治疗后全血低切黏度、全血高切黏度、血浆比黏度、纤维蛋白水平均低于治疗前,且观察组均低于对照组(P<0.05);两组治疗后血清CXCL9水平均低于治疗前,且观察组低于对照组(P<0.05);两组治疗过程中均未见严重不良反应,仅有极少数患者出现轻微恶心、呕吐症状。结论益气养心方治疗冠心病室性心律失常临床疗效较佳,可调低血清CXCL9水平,减轻心肌损伤,改善心肌的血液流变学指标,促进心律失常改善,且治疗安全性较高。

关键词：益气养心方冠心病室性心律失常心肌缺血血液流变学 CXC趋化因子配体9 临床疗效

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Working Mechanism of a Kind of Non-resonant Linear Piezoelectric Motor with Flexible Driving End

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第5期35卷 749-759页

作者： Chen Xifu huang weiqing Lu Qian Li Ming Ren Yaoqing School of Mechanical Engineering Yancheng Institute of Technology State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

A non-resonant piezoelectric linear motor with a flexible driving end,which has an extensive working frequency range and good operation stability,is studied theoretically and *** on the microscopic vibration characteristics of the motor stator,the longitudinal vibration model is established for the whole motor *** to the Coulomb friction model and the motor vibration model,the friction mechanism of the nonresonant piezoelectric linear motor is investigated by dynamical analysis of the whole motor ***,the vibration characteristics and mechanical output characteristics of the stator are simulated and experimentally studied on the basis of the friction drive mechanism ***,both the simulation and experimental results show that this kind of motor remain stable in the frequency domain from 2.2 kHz to 3.5 kHz and that when the pre-stress is 4 Nand the driving voltage is 90 V,the maximum velocity of the motor is above 4 mm/s and the maximum thrust is nearly 0.5 N.

关键词： piezoelectric motor non-resonance friction drive principle flexible drive end

Review on formation mechanism analysis method and control strategy of urban haze in China

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1572-1577页

作者： weiqing huang Lirong Cai Haifeng Dang Zhe Jiao Hongbo Fan Faliang Cheng School of Environment and Civil Engineering Guangdong Engineering and Technology Research Center for Advanced NanomaterialsDongguan University of TechnologyDongguan 523808China Guangdong Provincial Key Lab of Green Chemical Product Technology South China University of TechnologyGuangzhou 510640China

Due to the rapid urbanization and industrialization,and excessive consumption of fossil fuel,haze weather characterized by PM2.5 has become a severe pollution problem in major Chinese cities recently,which has harmful effect on the air quality,visibility,clime system and human *** indicate suitable directions for the prevention and control of haze pollution,the pollutant source apportionment and formation mechanism of urban haze should be figured out *** this work,we briefly review the frequently-used methods for PM2.5 source apportionment and formation mechanism analysis of urban haze based on normal perspective in recent ***,based on the new perspective of systematic methodology,the utilization of fault tree approach for the causation mechanism analysis of urban haze is significantly introduced and ***,the recent progress on controlling strategies of urban haze in China is also synoptically introduced and *** is expected that more effective tool/method can be found,developed and employed for the causation mechanism analysis and risk management of urban haze in China.

关键词： Urban haze Fossil fuel Formation Sustainability

TransTM: A device-free method based on time-streaming multiscale transformer for human activity recognition

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基于敏感特征深度域关联的Android恶意应用检测方法

Defence technology 2024年第2期

作者： Yi Liu weiqing huang Shang Jiang Bobai Zhao Shuai Wang Siye Wang Yanfang Zhang

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信息安全学报 2024年第3期9卷 191-203页

作者：姜建国李松喻民李罡刘超李梅梅黄伟庆中国科学院信息工程研究所北京100093 中国科学院大学网络空间安全学院北京100093 迪肯大学信息技术学院吉朗澳大利亚

利用机器学习或深度学习算法进行Android恶意应用的检测是当前主流方法,取得了一定的效果。然而,多数方法仅关注应用的权限和敏感行为等信息,缺乏对敏感行为协同的深度分析,导致恶意应用检测准确率低。对敏感行为协同深度分析的挑战主... 详细信息

利用机器学习或深度学习算法进行Android恶意应用的检测是当前主流方法,取得了一定的效果。然而,多数方法仅关注应用的权限和敏感行为等信息,缺乏对敏感行为协同的深度分析,导致恶意应用检测准确率低。对敏感行为协同深度分析的挑战主要有两个:表征敏感特征域关联和基于敏感特征域关联的深层分析与检测。本文提出了一种新的Android恶意应用检测模型GCNDroid,基于敏感特征域关联关系图描述的应用程序主要敏感行为以及敏感行为之间的域关联关系来有效地检测Android恶意应用。首先,为了筛选出对分类更加敏感的特征,同时减少图节点的数量,加速分析,本文构建了敏感特征字典。接着,定义类或者包为域,在同一个域中的敏感特征具有域关联关系。通过敏感特征所在域的相对范围,构造敏感特征之间不同的域关联权重,生成敏感特征域关联关系图,敏感特征域关联关系图可以准确表征特定功能模块中的敏感行为,以及敏感行为之间的完整关系。然后,基于敏感特征域关联关系图,设计基于图卷积神经网络的深度表征,构建Android恶意应用检测模型GCNDroid。在实践中,GCNDroid还可以利用新的敏感特征不断更新,以适应移动应用程序新的敏感行为。最后,本文对GCDNroid进行了系统评估,召回率、调和平均数、AUC等重要指标均超过96%。与传统的机器学习算法(支持向量机和决策树)和深度学习算法(深度神经网络和卷积神经网络)相比,GCNDroid取得了预期的效果。

关键词： Android恶意应用域关联图卷积神经网络敏感特征

An end-to-end text spotter with text relation networks

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Cybersecurity 2021年第1期4卷 91-103页

作者： Jianguo Jiang Baole Wei Min Yu Gang Li Boquan Li Chao Liu Min Li weiqing huang Institute of Information Engineering Chinese Academy of SciencesBeijingChina School of Cyber Security University of Chinese Academy of ScienceBeijingChina Centre for Cyber Security Research and Innovation Deakin UniversityGeelongAustralia

Reading text in images automatically has become an attractive research topic in computer ***,end-to-end spotting of scene text has attracted significant research attention,and relatively ideal accuracy has been achieved on several ***,most of the existing works overlooked the semantic connection between the scene text instances,and had limitations in situations such as occlusion,blurring,and unseen characters,which result in some semantic information lost in the text *** relevance between texts generally lies in the scene *** the perspective of cognitive psychology,humans often combine the nearby easy-to-recognize texts to infer the unidentifiable *** this paper,we propose a novel graph-based method for intermediate semantic features enhancement,called Text Relation ***,we model the co-occurrence relationship of scene texts as a *** nodes in the graph represent the text instances in a scene image,and the corresponding semantic features are defined as representations of the *** relative positions between text instances are measured as the weights of edges in the established ***,a convolution operation is performed on the graph to aggregate semantic information and enhance the intermediate features corresponding to text *** evaluate the proposed method through comprehensive experiments on several mainstream benchmarks,and get highly competitive *** example,on the SCUT-CTW1500,our method surpasses the previous top works by 2.1%on the word spotting task.

关键词： Scene text spotting Graph convolutional network Visual reasoning

重复经颅磁刺激对孤独症谱系障碍儿童心理行为及情绪的影响

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当代医学 2024年第16期30卷 18-21页

作者：詹英杰文宇黄伟庆陶容妹湛江市妇幼保健计划生育服务中心儿童康复科广东湛江524038

目的探讨重复经颅磁刺激对孤独症谱系障碍儿童心理行为及情绪的影响。方法选取2021年6月至2023年2月湛江市妇幼保健计划生育服务中心治疗的120例孤独症谱系障碍患儿作为研究对象,按照治疗时间段分为对照组(2021年6月至2022年5月,n=60)... 详细信息

目的探讨重复经颅磁刺激对孤独症谱系障碍儿童心理行为及情绪的影响。方法选取2021年6月至2023年2月湛江市妇幼保健计划生育服务中心治疗的120例孤独症谱系障碍患儿作为研究对象,按照治疗时间段分为对照组(2021年6月至2022年5月,n=60)与观察组(2022年6月至2023年2月,n=60)。对照组进行常规康复治疗,观察组在联合常规治疗的基础上进行重复经颅磁刺激治疗。比较两组临床疗效、治疗前后孤独症行为量表(autism behavior scale,ABC)评分、0~6岁小儿发育商(developmental quotient,DQ)评分、Conners儿童行为问卷(父母问卷)评分。结果观察组治疗总有效率为93.33%,高于对照组的80.00%,差异有统计学意义(P<0.05)。治疗后,两组ABC量表语言功能、社会交往、躯体运动、感觉、自理等维度评分和量表总分均低于治疗前,且观察组低于对照组,差异有统计学意义(P<0.05)。治疗后,两组DQ量表适应、精细动作、社交、语言、大运动评分均高于治疗前,且观察组高于对照组,差异有统计学意义(P<0.05)。治疗后,两组品行问题、多动指数评分和总分均低于治疗前,且观察组低于对照组,差异有统计学意义(P<0.05)。结论孤独症谱系障碍儿童采用重复经颅磁刺激治疗,能有效改善其心理情绪,纠正其孤独症行为,疗效确切。

关键词：重复经颅磁刺激孤独症谱系障碍心理行为心理情绪