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Geotechnical engineering blasting:a new modal aliasing cancellation methodology of vibration signal de-noising

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Earthquake Engineering and Engineering Vibration 2022年第2期21卷 313-323页

作者： Yi Wenhua Yan Lei wang zhenhuan Yang Jianhua Tao Tiejun Liu Liansheng School of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou 341000China School of Civil Engineering and Architecture Nanchang UniversityNanchang 330031China School of Civil Engineering Guizhou UniversityGuiyang 550025China

In the present study of peak particle velocity(PPV)and frequency,an improved algorithm(principal empirical mode decomposition,PEMD)based on principal component analysis(PCA)and empirical mode decomposition(EMD)is proposed,with the goal of addressing poor filtering de-noising effects caused by the occurrences of modal aliasing phenomena in EMD blasting vibration signal decomposition *** results showed that frequency of intrinsic mode function(IMF)components decomposed by PEMD gradually decreases and that the main frequency is unique,which eliminates the phenomenon of modal *** the simulation experiment,the signal-to-noise(SNR)and root mean square errors(RMSE)ratio of the signal de-noised by PEMD are the largest when compared to EMD and ensemble empirical mode decomposition(EEMD).The main frequency of the de-noising signal through PEMD is 75 Hz,which is closest to the frequency of the noiseless simulation *** geotechnical engineering blasting experiments,compared to EMD and EEMD,the signal de-noised by PEMD has the lowest level of distortion,and the frequency band is distributed in a range of 0-64 Hz,which is closest to the frequency band of the blasting vibration *** addition,the proportion of noise energy was the lowest,at 1.8%.

关键词： blasting vibration frequency empirical mode decomposition modal aliasing de-noising

Facile detection of pesticides using atmospheric pressure matrix-assisted laser desorption ionization mass spectrometry with multi-walled carbon nanotubes-based matrix

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Chinese Chemical Letters 2023年第1期34卷 569-573页

作者： Sijian Chen Huanxi Zhao Lili Jiao zhenhuan wang Mengya Zhao Lu Tian Yang Xiu Shuying Liu Jilin Ginseng Academy Changchun University of Chinese MedicineChangchun 130117China Changchun Institute of Applied Chemistry Chinese Academy of ScienceChangchun 130022China

A novel atmospheric pressure matrix-assisted laser desorption ionization mass spectrometry(AP-MALDIMS)method was established for the facile detection of pesticides in ambient *** kinds of multi-walled carbon nanotubes(MWCNTs)-based matrix were synthesized and utilized to enhance the ionization efficiency of ***,anilinopyrimidine,carbamate,triazine,triazole and benzimidazole pesticides were directly desorbed and ionized from MWCNTs-based matrix in ambient environment,showing clear background and good *** a comparison,Fe3O4-doped MWCNTs improved the intensity of pesticide ions more than the other three ***,MWCNTs-based matrix exhibited better performance than organic *** analysis of pesticides using APMALDI-MS was validated to be adequate linearity,repeatability and ***,AP-MALDI-MS combined with MWCNTs-based matrix enables the directly qualitative and quantitative analysis of pesticides in ambient environment.

关键词： Atmospheric pressure MALDI Pesticides MWCNTs-based matrix Ambient ionization

Regulation of specific abnormal calcium signals in the hippocampal CA1 and primary cortex M1 alleviates the progression of temporal lobe epilepsy

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Neural Regeneration Research 2024年第2期19卷 425-433页

作者： Feng Chen Xi Dong zhenhuan wang Tongrui Wu Liangpeng Wei Yuanyuan Li Kai Zhang Zengguang Ma Chao Tian Jing Li Jingyu Zhao Wei Zhang Aili Liu Hui Shen Laboratory of Neurobiology School of Biomedical EngineeringTianjin Medical UniversityTianjinChina Institute for Translational Neuroscience the Second Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Institute for Translational Brain Research Fudan UniversityShanghaiChina Department of Radiology the Affiliated Drum Tower Hospital of Nanjing University Medical SchoolNanjingJiangsu ProvinceChina Innovative Institute of Chinese Medicine and Pharmacy Shandong University of Traditional Chinese MedicineJinanChina Department of Anesthesiology Tianjin Medical University General HospitalTianjinChina Department of Orthopaedics Tianjin Medical University General HospitalTianjinChina Tianjin Eye Hospital Tianjin Eye InstituteTianjin Key Lab of Ophthalmology and Visual ScienceTianjinChina Laboratory of Neurobiology School of Basic Medical SciencesTianjin Medical UniversityTianjinChina

Temporal lobe epilepsy is a multifactorial neurological dysfunction syndrome that is refractory,resistant to antiepileptic drugs,and has a high recurrence *** pathogenesis of temporal lobe epilepsy is complex and is not fully *** calcium dynamics have been implicated in temporal lobe ***,the effect of fluctuating calcium activity in CA1 pyramidal neurons on temporal lobe epilepsy is unknown,and no longitudinal studies have investigated calcium activity in pyramidal neurons in the hippocampal CA1 and primary motor cortex M1 of freely moving *** this study,we used a multichannel fiber photometry system to continuously record calcium signals in CA1 and M1 during the temporal lobe epilepsy *** found that calcium signals varied according to the grade of temporal lobe epilepsy *** particular,cortical spreading depression,which has recently been frequently used to represent the continuously and substantially increased calcium signals,was found to correspond to complex and severe behavioral characteristics of temporal lobe epilepsy ranging from gradeⅡto gradeⅤ.However,vigorous calcium oscillations and highly synchronized calcium signals in CA1 and M1 were strongly related to convulsive motor *** inhibition of pyramidal neurons in CA1 significantly attenuated the amplitudes of the calcium signals corresponding to gradeⅠ*** addition,the latency of cortical spreading depression was prolonged,and the above-mentioned abnormal calcium signals in CA1 and M1 were also significantly ***,it was possible to rescue the altered intracellular calcium *** simultaneous analysis of calcium signals and epileptic behaviors,we found that the progression of temporal lobe epilepsy was alleviated when specific calcium signals were reduced,and that the end-point behaviors of temporal lobe epilepsy were *** results indicate that the calcium dynamic between CA1 and M1 may reflect sp

关键词： Ca^(2+) calcium signals chemogenetic methods hippocampus primary motor cortex pyramidal neurons temporal lobe epilepsy

Integral 2-Order Sliding Mode Control for Servo Turntable Based on Extended State Observer

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Integral 2-Order Sliding Mode Control for Servo Turntable Ba...

加速度计在精密离心机上的标定方法与误差分析

第37届中国控制会议

作者： Zhongze Cai Qingshuang Zeng Guhao Sun zhenhuan wang Space Control and Inertial Technology Research Center Harbin Institute of Technology

This paper investigates a globally robust and globally finite-time convergent controller for a servo turntable *** control method is formulated by using a 2-order sliding mode control（SMC） with integral sliding surface applying to an auxiliary system. To eliminate the need of advanced information, extended state observer（ESO） is applied. The proposed controller in this paper is based on geometric homogeneity approach which can ensure finite-time convergence. The finitetime stability and convergence of ESO and controller are analysed based on both the Lyapunov stability theory and negative homogeneity approach. To illustrate the effectiveness of the proposed results in this work, simulations and comparisons are shown for the angle position tracking of servo turntable system.

关键词： Servo Turntable 2-order SMC ESO Geometric Homogeneity Control Integral Sliding Surface

来源： cnki会议评论

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中国惯性技术学报 2019年第1期27卷 121-128页

作者：孙闯任顺清王振桓空间控制与惯性技术研究中心哈尔滨工业大学哈尔滨150080

为了提高加速度计非线性误差系数在离心机上的标定精度,应对离心机的误差源进行准确地分析和有效地分离。首先,通过分析双轴离心机的误差源建立了相应的坐标系,利用齐次变换法推导了加速度计在离心机上的精确比力输入并建立了加速度计... 详细信息

为了提高加速度计非线性误差系数在离心机上的标定精度,应对离心机的误差源进行准确地分析和有效地分离。首先,通过分析双轴离心机的误差源建立了相应的坐标系,利用齐次变换法推导了加速度计在离心机上的精确比力输入并建立了加速度计的标定模型。其次,分析了相应误差项对加速度计零偏、标度因子和非线性误差项系数的标定影响,设计了加速度计在离心机上标定时的误差分离方法。最后,通过实验对加速度计的误差模型系数进行了辨识。结果表明,该方法能够准确分离出失准角误差和偏心误差,非线性误差系数的标定不确定度量级为10^(-4),能够有效提高加速度计的标定精度。

关键词：加速度计标定离心机误差分析

基于冷却除湿混合技术消除白烟热交换系统的传热性能分析

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中国电机工程学报 2023年第16期43卷 6348-6354页

作者：王振环王珊珊权宁哲滨州学院机电工程学院山东省滨州市256600 韩国鲜文大学机械工学部韩国天安牙山31640

燃煤电厂湿法脱硫后排出的白烟会造成视觉污染、水分和余热浪费等问题,因此有效治理白烟、推广烟气消白技术具有十分重要的工程意义。以湿法脱硫后形成的白烟污染问题为研究对象对其消除白烟热交换系统进行分析,探究不同工况下对其热交... 详细信息

燃煤电厂湿法脱硫后排出的白烟会造成视觉污染、水分和余热浪费等问题,因此有效治理白烟、推广烟气消白技术具有十分重要的工程意义。以湿法脱硫后形成的白烟污染问题为研究对象对其消除白烟热交换系统进行分析,探究不同工况下对其热交换系统温度、绝对湿度降低和冷却水热回收的影响。基于冷却除湿混合烟气技术方法,在冬季环境条件下对热交换系统进行实验研究,并使用摄像机拍摄混合区出口是否产生白烟。结果发现:当供气引风机和空气-水热交换器同时运行(工况3)时,废气和供气的温度变化最为显著,而且混合区出口温度和绝对湿度大幅度降低,降低约74.1℃和0.0879kg/kg。通过白烟可视化结果,证实白烟的产生机理因工况不同而不同,而且白烟产生量随不同工况的温度和绝对湿度降低而逐渐减少。

关键词：绝对湿度冷却除湿热交换器传热性能混合消除白烟

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关于进一步推进多元经营企业改革的思考

中国铁路 2006年第9期 59-61页

作者：王振寰上海铁路局安徽青芦铁路有限责任公司生产部经营部经理安徽宿州234000

多元经营企业与运输主业关系密切,是铁路跨越式发展的重要组成部分。因此,必须创新体制机制,调整产业结构,加快多元经营企业改革。积极探索并实行符合多元经营运行规律的管理体制;按照现代企业制度要求,建立产权明晰、产权转让灵活、保... 详细信息

多元经营企业与运输主业关系密切,是铁路跨越式发展的重要组成部分。因此,必须创新体制机制,调整产业结构,加快多元经营企业改革。积极探索并实行符合多元经营运行规律的管理体制;按照现代企业制度要求,建立产权明晰、产权转让灵活、保障铁路多元经营资产保值增值的资产管理、监督和营运体制;从铁路实际和区域特点出发,发挥优势,做强重点产业。推进多元经营企业改革,要加快资源整合和企业重组,以股份制改革为目标,规范企业改制,完善站段多经脱钩工作,加快非运输业单位改革,落实辅业资产管理机构权责,并加大对多元经营的扶持力度。

关键词：多元经营企业改革重组改制

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环氧化功能碳纳米管改性氨基PPS

复合材料学报 2016年第11期33卷 2468-2476页

作者：王海霞李振环程博闻天津工业大学材料科学与工程学院中空纤维膜材料与膜过程国家重点实验室天津300387

聚苯硫醚(PPS)是绝缘和疏水性材料,一定程度上限制了其在某些特定领域的应用。利用氨基改性PPS(NPPS),并利用环氧功能化多壁碳纳米管(EFMWCNTs)与NPPS共价作用形式,采用溶液共混制备了EFMWCNTs/NPPS导电复合材料。利用FTIR、XPS、XRD、F... 详细信息

聚苯硫醚(PPS)是绝缘和疏水性材料,一定程度上限制了其在某些特定领域的应用。利用氨基改性PPS(NPPS),并利用环氧功能化多壁碳纳米管(EFMWCNTs)与NPPS共价作用形式,采用溶液共混制备了EFMWCNTs/NPPS导电复合材料。利用FTIR、XPS、XRD、FESEM、TEM、DSC、TGA和半导体粉末电导率测试仪系统表征了复合材料的结构与性能。表征结果显示:PPS的链段上引入氨基后,PPS的熔融峰和结晶峰消失。NPPS利用EFMWCNTs进一步改性后,EFMWCNTs/NPPS导电复合材料的热稳定性相比NPPS增加,原因是EFMWCNTs与NPPS之间的共价作用有效提高了EFMWCNTs在NPPS中的分散性。EFMWCNTs/NPPS复合材料的电导率随EFMWCNTs添加量增加而增加,添加10wt%的EFMWCNTs时,复合材料的电导率为6.1×10-2 S/cm。

关键词：氨基改性聚苯硫醚电导率热性能功能化共价作用

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冷藏/冷冻车辆用制冷机组的性能实验及模拟

制冷学报 2024年第1期45卷 129-136页

作者：王振环崔然成王珊珊滨州学院机电工程学院滨州256600 韩国制冷空调认证中心华城市18608

为研究冷藏/冷冻车辆用10 kW制冷机组不同参数对性能的影响,本文采用实验和模拟方法分析了制冷循环系统的制冷能力、COP和压力性能,并通过分别改变制冷剂充注量、过热度和制冷剂种类对其进行了实验和模拟研究。结果表明:随着制冷剂充注... 详细信息

为研究冷藏/冷冻车辆用10 kW制冷机组不同参数对性能的影响,本文采用实验和模拟方法分析了制冷循环系统的制冷能力、COP和压力性能,并通过分别改变制冷剂充注量、过热度和制冷剂种类对其进行了实验和模拟研究。结果表明:随着制冷剂充注量和过热度的变化,制冷机组的制冷能力和COP表现出不同的趋势。模拟值和实验值的制冷能力和COP误差分别为6.4%和8.5%,所有结果均在10%以内。与制冷剂充注量相比,制冷机组的性能变化更多地依赖于过热度的变化。在制冷循环过热度为4℃、制冷剂充注量为7.4 kg时,制冷机组的制冷能力和COP最佳。通过数值模拟分析了应用于制冷循环系统的制冷剂R449A,比采用R404A的系统COP高约4%。确认了制冷剂R449A可以替代R404A使用。

关键词：冷藏车制冷机组制冷能力过热度 COP R449A