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Adaptive sensitive frequency band selection for VMD to identify defective components of an axial piston pump

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Chinese Journal of Aeronautics 2022年第1期35卷 250-265页

作者： Anil KUMAR C.P.GANDHI Hesheng TANG Govind VASHISHTHA Rajesh KUMAR Yuqing ZHOU jiawei xiang College of Mechanical and Eilectrical Engineering Wenzhou UniversityWenzhou 325035China Amity University Uttar Pradesh Noida 201313India Ray at Bahru University Mohali 140104India Sant Longowal Institute of Engineering and Technology Longowal 148106India

The underlying study investigates single valued neutrosophic entropy based adaptive sensitive frequency band selection for variational mode decomposition(VMD)for the purpose of identifying defective components in an axial *** proposed methodology is applied in the following ***,VMD is applied for decomposing vibration signals into various frequency bands,called as *** computing energy of each VMD,the lower(minimum)and upper(maximum)bounds from these energy readings are extracted for defect conditions,such as outer race,inner race,worn piston,faulty cylinder and valve plate,and blocked hole of the ***,energy interval ranges are obtained and further converted into the form of single valued neutrosophic sets(SVNSs).Then,the proposed neutrosophic entropy measure is deployed for quantifying the non-linear connection between each bearing defect conditions and various frequency *** mode having maximum neutrosophic entropy value is designated to the“most sensitive”frequency ***,envelope demodulation is applied to the most sensitive selected frequency band for finding defective *** proposed neutrosophic entropy and VMD based methodology is effective in providing a better insight for selecting suitable frequency band for carrying out envelope demodulation in comparison to existing methods.

关键词： Axial piston pump Frequency band selection Reciprocating machinery Rotating machinery Trigonometric neutrosophic entropy Variational mode decomposition Vibration

机械故障数值模拟驱动的生成式对抗网络及智能诊断原理

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中国科学：技术科学 2021年第3期51卷 341-355页

作者：向家伟温州大学机电工程学院温州325035

预测性维护是智能制造领域潜在爆发点.人工智能诊断作为其关键一环,成为近年来工程领域研究的热点,发展出一系列极具应用前景的诊断方法.众所周知,完备故障样本是激活智能诊断模型的关键,然而,在工程实践中,机械系统实际发生的故障远多... 详细信息

预测性维护是智能制造领域潜在爆发点.人工智能诊断作为其关键一环,成为近年来工程领域研究的热点,发展出一系列极具应用前景的诊断方法.众所周知,完备故障样本是激活智能诊断模型的关键,然而,在工程实践中,机械系统实际发生的故障远多于我们能预先从运行状态下获得的故障样本.因此,基于机械故障数值模拟驱动的生成式对抗网络,获得完备故障样本,架设人工智能模型与实际运行的机械系统故障诊断之间的桥梁,提出新型智能诊断原理意义重大.首先,采用有限元仿真得到机械系统缺失故障样本,与预先获得的故障样本一起,组成相对完备故障样本.其次,为进一步提高故障样本质量,利用生成式对抗网络生成大量与相对完备故障样本相似的新样本,与相对完备故障样本一起,构成完备故障样本(合成故障样本).最后,以完备故障样本作为训练样本,以待检测未知故障样本作为测试样本,基于人工智能模型进行故障分类.以故障轴承公共数据集、故障齿轮实验台、故障转子实验台为例,通过与常用的人工智能诊断模型比较研究,验证了所提出的智能诊断原理有效性,为推广智能诊断模型至实际运行的机械系统带来了新希望.

关键词：机械传动系统故障数值模拟生成式对抗网络人工智能诊断

Comparative evaluation of SPE methods for biotoxicity assessment of water and wastewater:Linkage between chemical extracting efficiency and biotoxicity outcome

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Journal of Environmental Sciences 2024年第8期142卷 33-42页

作者： jiawei Zhou Shihao Wang Xiwei He Hongqiang Ren Xu-xiang Zhang State Key Laboratory of Pollution Control and Resource Reuse School of EnvironmentNanjing UniversityNanjing 210023China

Biotoxicity assessment results of environmental waters largely depend on the sample extraction protocols that enrich pollutants to meet the effect-trigger thresholds of ***,more chemical mixture does not necessarily translate to higher combined ***,there is a need to establish the link between chemical extracting efficiency and biotoxicity outcome to standardize extraction methods for biotoxicity assessment of environmental *** study compares the performance of five different extraction phases in solid phase extraction(SPE),namely HLB,HLB+Coconut,C18 cartridge,C18 disk and Strata-X,and evaluated their chemical extracting efficiencies and biotoxicity *** quantitatively assessed cytotoxicity,acute toxicity,genotoxicity,estrogenic activity,and neurotoxicity of the extracts using in vitro bioassays and characterized the chemical extracting efficiencies of the SPE methods through chemical recoveries of 23 model compounds with different polarities and total organic *** Pareto ranking,we identified HLB+Coconut as the optimal SPE method,which exhibited the highest level of water sample biotoxicity and recovered the most chemicals in water *** found that the biotoxicity outcomes of the extracted water samples significantly and positively correlated with the chemical extracting efficiencies of the SPE ***,we observed synchronous changing patterns in biotoxicity outcome and chemical extracting efficiencies in response to increasing sample volumes per cartridge(SVPC)during *** findings underscore that higher chemical extracting efficiency of SPE corresponds to higher biotoxicity outcome of environmental water samples,providing a scientific basis for standardization of SPE methods for adequate assessment of biotoxicities of environmental waters.

关键词： Biotoxicity Chemical recovery Solid phase extraction Surface water Wastewater

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数值模型驱动的传动系统故障个性化诊断原理

机械工程学报 2021年第15期57卷 116-128页

作者：向家伟温州大学机电工程学院温州325035

如何获得机械传动系统大量反映实际运行状态的故障样本,是制约人工智能诊断模型走向工程应用的瓶颈。基于个体差异的精准诊断需求,提出机械传动系统个性化故障诊断基本原理,通过建立机械传动系统数值模型,进行仿真分析,获得故障样本,解... 详细信息

如何获得机械传动系统大量反映实际运行状态的故障样本,是制约人工智能诊断模型走向工程应用的瓶颈。基于个体差异的精准诊断需求,提出机械传动系统个性化故障诊断基本原理,通过建立机械传动系统数值模型,进行仿真分析,获得故障样本,解决故障诊断过程中故障特征信息缺乏的短板,从而激活人工智能诊断方法。以轴承、齿轮传动、转子系统等机械传动系统为例,构建完好结构有限元模型,开展模型修正,获得具有一定精度的仿真模型。预定义多类故障并添加至具有一定精度的有限元模型,计算生成故障样本集,作为人工智能诊断模型的训练样本,用于待诊断测试样本分类。任意选取的支持向量机、极限学习机、卷积神经网络等人工智能诊断模型故障分类实验结果表明:所提出机械传动系统故障诊断的个性化诊断原理,具有较强的普适性与可拓展性。

关键词：机械传动系统故障个性化诊断人工智能诊断模型分类

Maxblend桨和多层组合桨搅拌槽内气液分散特性研究

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化工设备与管道 2024年第4期61卷 31-40页

作者：赵阳谢明辉向家伟刘肖肖李帅亮吕世军吴亮周国忠张庆华杨超温州大学机电工程学院浙江温州325035 浙江长城搅拌设备股份有限公司浙江温州325019 中石化上海工程公司上海200120 中国科学院过程工程研究所中国科学院绿色过程与工程重点实验室北京100190

针对高密度聚乙烯淤浆聚合反应的低黏物料体系,以空气-水为研究对象,研究了Maxblend搅拌桨和利用三叶后掠式搅拌桨HQ150、抛物线圆盘涡轮式搅拌桨BTD170、三宽叶旋桨式搅拌桨KHX170、桨叶安装角度为δ=45°的斜叶圆盘涡轮式搅拌桨ZY160... 详细信息

针对高密度聚乙烯淤浆聚合反应的低黏物料体系,以空气-水为研究对象,研究了Maxblend搅拌桨和利用三叶后掠式搅拌桨HQ150、抛物线圆盘涡轮式搅拌桨BTD170、三宽叶旋桨式搅拌桨KHX170、桨叶安装角度为δ=45°的斜叶圆盘涡轮式搅拌桨ZY160和平直叶圆盘涡轮式搅拌桨PY160构成的3种组合桨搅拌槽内的气液分散与传质特性。结果表明,拟合的气含率、气液相界面积和体积氧传质系数的经验关联式与实验数据吻合较好。Maxblend桨的PG/P受通气影响最小,其次是桨型组合3。通气量为0.6 vvm时,相同功耗下桨型组合3的气含率最高,Maxblend桨近壁区域的d32最小,功率较高时,桨型组合1、2、3中的近壁d32最小的是桨型组合3,气液相界面积最大的是桨型组合3,液相氧传质系数最大的是桨型组合1,桨型组合1、2、3的传质性能相当,且优于Maxblend桨。

关键词：搅拌功率消耗气含率气泡尺寸气液传质

Ru-Ni alloy nanosheets as tandem catalysts for electrochemical reduction of nitrate to ammonia

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Nano Research 2024年第6期17卷 4815-4824页

作者： Xingchao You jiawei Xu Zechao Zhuang Junkai Xia Suwen Wang Haiyan Wei Yongfu Li Yanjiang Cai Hai xiang Bing Yu State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Ecological-Environment&Health College(EEHC) Zhejiang A&F UniversityHangzhou 311300China Jiangsu Key Laboratory of Numerical Simulation of Large Scale Complex Systems and School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Department of Chemistry Tsinghua UniversityBeijing 100084China Department of Chemical Engineering Columbia UniversityNew YorkNY 10027USA

Developing electrocatalysts that exhibit both high activity and ammonia selectivity for nitrate reduction is a significant and demanding challenge,primarily due to the complex nature of the multiple-electron reduction process *** encouraging approach involves coupling highly active precious metals with transition metals to enhance catalytic performance through ***,we report a ruthenium-nickel alloy catalyst with nanosheets(Ru-Ni NSs)structure that achieves a remarkable ammonia Faradaic efficiency of approximately 95.93%,alongside a yield rate of up to 6.11 g·h^(−1)·cm^(−2).Moreover,the prepared Ru-Ni NSs exhibit exceptional stability during continuous nitrate reduction in a flow reactor for 100 h,maintaining a Faradaic efficiency of approximately 90%and an ammonia yield of 37.4 mg·L^(−1)·h^(−1)using 0.05 M nitrate alkaline *** studies reveal that the catalytic process follows a two-step pathway,in which HONO serves as a migration *** presence of a partially oxidized Ru(002)surface enhances the adsorption of nitrate and facilitates the release of the migration intermediate by adjusting the strength of the electrostatic and covalent interactions between the adsorbate and the surface,*** the other hand,the Ni(111)surface promotes the utilization of the migration intermediate and requires less energy for NH_(3)*** tandem process contributes to a high catalytic activity of Ru-Ni NSs towards nitrate reduction.

关键词： alloy catalyst nitrate reduction ammonia synthesis Faradaic efficiency

二维局域共振型声子晶体微腔结构的带隙特性研究

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功能材料 2015年第9期46卷 9102-9105,9110页

作者：刘帽向家伟桂林电子科技大学机电工程学院广西桂林541004 温州大学机电工程学院浙江温州325035

利用有限元法研究了含十字型所形成的二维局域共振型微腔声子晶体结构的声波带隙特性。同时计算了最低带隙带边对应模态的位移分布和结构的传输谱。研究结果表明,含微腔结构的声子晶体在较低频率域内出现了完全带隙且带隙边缘的起始频率... 详细信息

利用有限元法研究了含十字型所形成的二维局域共振型微腔声子晶体结构的声波带隙特性。同时计算了最低带隙带边对应模态的位移分布和结构的传输谱。研究结果表明,含微腔结构的声子晶体在较低频率域内出现了完全带隙且带隙边缘的起始频率低,然而对于无微腔结构的类四边形声子晶体板中,则无第二带隙出现,并且第一带隙频率宽度较窄。微腔结构是产生局域共振以及出现低频带隙的最主要的原因。该研究为声子晶体在低频减振和噪音控制的工程应用方面提供了有益的支持。

关键词：声子晶体带隙有限元法微腔

基于增强聚类分割与L-峭度的Teager能量算子解调诊断轴向柱塞泵故障

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机械工程学报 2018年第18期54卷 1-10页

作者：高强向家伟汤何胜温州大学机电工程学院温州325035 浙江大学流体动力与机电系统国家重点实验室杭州310027

振动信号中的周期性脉冲对于轴向柱塞泵故障诊断具有重要意义,但在工作状态下,轴向柱塞泵的振动信号经常会受到背景噪声和柱塞往复运动引起的自然周期性脉冲的污染,故障特征提取是轴向柱塞泵故障诊断的一个难点。为解决这个问题,提出基... 详细信息

振动信号中的周期性脉冲对于轴向柱塞泵故障诊断具有重要意义,但在工作状态下,轴向柱塞泵的振动信号经常会受到背景噪声和柱塞往复运动引起的自然周期性脉冲的污染,故障特征提取是轴向柱塞泵故障诊断的一个难点。为解决这个问题,提出基于增强聚类分割与L-峭度的Teager能量算子解调方法。与传统的聚类分割方法不同,增强后的算法是一种两周期的方法,能够有效从背景噪声和自然周期性脉冲中提取故障特征。L-峭度在识别周期性脉冲方面与峭度类似,但不像峭度对离群值那么敏感。Teager能量算子解调计算简便,比传统的希尔伯特解调更适合用来进行故障特征提取。为说明该方法的可行性,进行仿真模拟和试验数据研究,并将结果与传统的聚类分割方法进行了比较。结果表明,该方法能够有效地检测轴向柱塞泵的缸体和轴承故障。

关键词：增强聚类分割 L-峭度 Teager能量算子解调轴向柱塞泵故障诊断

CircZFR promotes colorectal cancer progression via stabilizing BCLAF1 and regulating the miR-3127-5p/RTKN2 axis

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Science China(Life Sciences) 2024年第9期67卷 1881-1898页

作者： Jiaxin Chen Huijuan Wang Jianbin Xu Engeng Chen Qing Meng jiawei Wang Haoyi xiang Wei Zhou Ge Shan Zhenyu Ju Zhangfa Song Department of Colorectal Surgery Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310016China Key Laboratory of Biological Treatment of Zhejiang Province Hangzhou 310016China Department of Pulmonary and Critical Care Medicine Regional medical center for National Institute of Respiratory DiseaseSir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310016China Key Laboratory of Regenerative Medicine of Ministry of Education Institute of Aging and Regenerative MedicineJinan UniversityGuangzhou 510632China Department of Breast Surgery the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Department of Orthopedic Surgery the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China

Aberrant expression of circular RNAs(circ RNAs)is frequently linked to colorectal cancer(CRC).Here,we identified circ ZFR as a promising biomarker for CRC diagnosis and *** ZFR was upregulated in CRC tissues and serum exosomes and its level was linked to cancer incidence,advanced-stages,and *** both in vitro and in vivo settings,circ ZFR promoted the growth and spread while suppressing apoptosis of *** with circ ZFR overexpression promoted the proliferation and migration of cocultured CRC ***,epithelial splicing regulatory protein 1(ESRP1)in CRC cells may enhance the production of circ ***2-associated transcription factor 1(BCLAF1)bound to circ ZFR,which prevented its ubiquitinated ***,circ ZFR sponged mi R-3127-5p to boost rhotekin 2(RTKN2)*** TCP1-CD-QDs nanocarrier was able to carry and deliver circ ZFR si RNA(si-circ ZFR)to the vasculature of CRC tissues and cells,which inhibited the growth of tumors in patient-derived xenograft(PDX)*** together,our results show that circ ZFR is an oncogenic circ RNA,which promotes the development and spread of CRC in a BCLAF1 and mi R-3127-5p-dependent *** ZFR is a possible serum biopsy marker for the diagnosis and a desirable target for further treatment of CRC.

关键词： circZFR exosome ESRP1 BCLAF1 miR-3127-5p nanoparticle(NP)