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Predicting the Reflection Coefficient of a Viscoelastic Coating Containing a Cylindrical Cavity Based on an Artificial Neural Network Model

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Computer Modeling in Engineering & Sciences 2022年第2期130卷 1149-1170页

作者： Yiping Sun Qiang Bai xuefeng zhao Meng Tao School of Mechanical Engineering Guizhou UniversityGuiyang550025China Aviation Academy Guizhou Open UniversityGuiyang550003China

A cavity viscoelastic structure has a good sound absorption performance and is often used as a reflective baffle or sound absorption cover in underwater acoustic structures.The acoustic performance field has become a key research direction worldwide.Because of the time-consuming shortcomings of the traditional numerical analysis method and the high cost of the experimental method for measuring the reflection coefficient to evaluate the acoustic performance of coatings,this innovative study predicted the reflection coefficient of a viscoelastic coating containing a cylindrical cavity based on an artificial neural network(ANN).First,themapping relationship between the input characteristics and reflection coefficient was analysed.When the elastic modulus and loss factor value were smaller,the characteristics of the reflection coefficient curve were more complicated.These key parameters affected the acoustic performance of the viscoelastic coating.Second,a dataset of the acoustic performance of the viscoelastic coating containing a cylindrical cavity was generated based on the finite elementmethod(FEM),which avoided a large number of repeated experiments.The minmax normalization method was used to preprocess the input characteristics of the viscoelastic coating,and the reflection coefficient was used as the dataset label.The grid search method was used to fine-tune the ANNparameters,and the prediction error was studied based on a 10-fold cross-validation.Finally,the error distributions were analysed.The average root means square error(RMSE)and the mean absolute percentage error(MAPE)predicted by the improved ANN model were 0.298%and 1.711%,respectively,and the Pearson correlation coefficient(PCC)was 0.995,indicating that the improved ANN model accurately predicted the acoustic performance of the viscoelastic coating containing a cylindrical cavity.In practical engineering applications,by expanding the database of the material range,cavity size and backing of the coating,the reflection coefficient of more sound-absorb

关键词： Coating acoustic performance artificial neural network predicting

A High-Efficiency Inversion Method for the Material Parameters of an Alberich-Type Sound Absorption Coating Based on a Deep Learning Model

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1693-1716页

作者： Yiping Sun Jiadui Chen Qiang Bai xuefeng zhao Meng Tao School of Mechanical Engineering Guizhou UniversityGuiyang550025China Aviation Academy Guizhou Open UniversityGuiyang550023China

Research on the acoustic performance of an anechoic coating composed of cavities in a viscoelastic material has recently become an area of great interest.Traditional forward research methods are unable to manipulate sound waves accurately and effectively,are difficult to analyse,have time-consuming solution processes,and have large optimization search spaces.To address these issues,this paper proposes a deep learning-based inverse research method to efficiently invert the material parameters of Alberich-type sound absorption coatings and rapidly predict their acoustic performance.First,an autoencoder(AE)model is pretrained to reconstruct the viscoelastic material parameters of an Alberich-type sound absorption coating,the material parameters are extracted into the latent feature space by the encoder,and the decoder model is saved.The internal relationship between the reflection coefficient and latent feature space is trained to establish a multilayer perceptron(MLP).Then,the reflection coefficients in the test set are input to the trained MLP and decoder models to automatically invert the material parameters.The accuracy of the inversion result is 95.08%.Finally,a predictive model is trained to rapidly predict the acoustic performance of the inverted material parameters.The speed of a single test target is 80 times faster than that of the finite element method(FEM).Furthermore,sound absorber material parameters with the best sound absorption performance and a three-band sound absorber are inverted,and their actual sound absorption performance is predicted by the proposed method.The proposed deep learning-based inversion research method provides a solution for low-frequency,wide-band,strong attenuation,and precisely controlled sound waves.It achieves an efficient inversion of material parameters and the rapid forecasting of acoustic performance.The training model can be used for a sound absorbing coating composed of irregular cavities in a viscoelastic material and predict its acoustic performance by only modifyin

关键词： Anechoic coating deep learning inversion research rapid forecasting

Versatile functions of RNA m6A machinery on chromatin

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Journal of Molecular Cell Biology 2022年第3期14卷 3-11页

作者： Tanjing Song Suli Lv Neng Li xuefeng zhao Xianyun Ma Yingying Yan Weixia Wang Lidong Sun Department of Biochemistry and Molecular Biology School of Basic Medicineongji Medical College Huazhong University of Science and TechnologyWuhan 430030China

m6A,a conserved and abundant modification on RNA,regulates RNA processing and function.RNA m6A machinery,including writers,erasers,and readers of m6A,is indispensable for m6A installation and function.Intriguingly,recent studies have revealed that m6A machinery can be recruited to chromatin by pleiotropic factors,including nascent RNA,transcription factors,regulatory RNA,histone modifications,and epigenetic machinery.Consequently,recruitment of m6A machinery can directly regulate chromatin biology,such as transcription,DNA damage repair,and DNA recombination beyond installation of m6A on nascent mRNA.Here,we discuss recent evidence showing that m6A machinery is targeted to chromatin and the direct biological consequences along with the underlying mechanisms.

关键词： m6A chromatin RNA methylation histone modifications epigenetics

Aerenchyma Formed Under Phosphorus Deficiency Contributes to the Reduced Root Hydraulic Conductivity in Maize Roots

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Journal of Integrative Plant Biology 2007年第5期49卷 598-604页

作者： Mingshou Fan Ruiqin Bai xuefeng zhao Jianhua Zhang College of Agronomy Inner Mongolia Agricultural University Huhhot 010018 China Department of Biology Hong Kong Baptist University Hong Kong China

Root hydraulic conductivity has been shown to decrease under phosphorus （P） deficiency. This study Investigated how the formation of aerenchyma is related to this change. Root anatomy, as well as root hydraulic conductivity was studied In maize （Zea mays L.） roots under different phosphorus nutrition conditions. Plant roots under P stress showed enhanced degradation of cortical cells and the aerenchyma formation was associated with their reduced root hydraulic conductivity, supporting our hypothesis that air spaces that form in the cortex of phosphorusstressed roots Impede the radial transport of water in a root cylinder. Further evidence came from the variation In aerenchyma formation due to genotypic differences. Five maize inbred lines with different porosity in their root cortex showed a significant negative correlation with their root hydraulic conductivity. Shoot relative water content was also found lower In P-deficient maize plants than that in P-sufficient ones when such treatment was prolonged enough, suggesting a limitation of water transport due to lowered root hydraulic conductivity of P-deficient plants.

关键词： aerenchyma maize （Zea mays） phosphorus deficiency root root hydraulic conductivity.

ZBP1(DAI/DLM-1) promotes osteogenic differentiation while inhibiting adipogenic differentiation in mesenchymal stem cells through a positive feedback loop of Wnt/β-catenin signaling

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Bone Research 2020年第2期8卷 219-228页

作者： xuefeng zhao Liang Xie Zhiyong Wang Jiongke Wang Hao Xu Xianglong Han Ding Bai Peng Deng State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesChinese Academy of Medical Sciences Research Unit of Oral Carcinogenesis and ManagementWest China Hospital of StomatologySichuan UniversityChengduSichuan 610041PR China Department of Orthodontics West China Hospital of StomatologySichuan UniversityChengduSichuan 610041PR China

The lineage specification of mesenchymal stem/stromal cells(MSCs) is tightly regulated by a wide range of factors. Recently, the versatile functions of ZBP1(also known as DAI or DLM-1) have been reported in the blood circulation and immune systems.However, the biological function of ZBP1 during the lineage specification of MSCs is still unknown. In the present study, we found that ZBP1 was upregulated during osteogenesis but downregulated during adipogenesis in mouse bone marrow-derived MSCs(m BMSCs). ZBP1 was highly expressed in osteoblasts but expressed at a relatively low level in marrow adipocytes. Knockdown of ZBP1 inhibited alkaline phosphataseactivity, extracellular matrix mineralization, and osteogenesis-related gene expression in vitro and reduced ectopic bone formation in vivo. Knockdown of ZBP1 also promoted adipogenesis in MSCs in vitro. Conversely, the overexpression of ZBP1 increased the osteogenesis but suppressed the adipogenesis of MSCs. When the expression of ZBP1 was rescued, the osteogenic capacity of ZBP1-depleted m BMSCs was restored at both the molecular and phenotypic levels.Furthermore, we demonstrated that ZBP1, a newly identified target of Wnt/β-catenin signaling, was required for β-catenin translocation into nuclei. Collectively, our results indicate that ZBP1 is a novel regulator of bone and fat transdifferentiation via Wnt/β-catenin signaling.

关键词： inhibited inhibiting versatile

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双荷载箱自平衡法在超长桩基承载力测试中的应用

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科技和产业 2024年第13期24卷 117-121页

作者：赵雪峰山西省交通科技研发有限公司太原030006

在黄河中游山西小北干流范围,地下以砂土、粉质黏土层等物理力学指标较低的地层为主。在这种复杂的地质条件下,为保证桥梁桩基承载力和上部结构的安全性要求,设计多采用大直径超长桩为主,施工难度较大,造价较高。双荷载箱自平衡法是指... 详细信息

在黄河中游山西小北干流范围,地下以砂土、粉质黏土层等物理力学指标较低的地层为主。在这种复杂的地质条件下,为保证桥梁桩基承载力和上部结构的安全性要求,设计多采用大直径超长桩为主,施工难度较大,造价较高。双荷载箱自平衡法是指根据试验方案规定,在桩身特定位置依次嵌入两个荷载箱,然后按照加载试验方案对荷载箱进行逐级分段加载,分别得出3段桩身的承载力,可以解决超长桩基试桩试验中的很多问题,为桩长优化设计提供数据支撑,具有广泛的应用前景。

关键词：双荷载箱自平衡法超长桩基

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内部质控样芹菜中总砷含量的不确定度评定

食品安全导刊 2024年第2期 80-83页

作者：赵雪峰宜兴市疾病预防控制中心江苏宜兴214206

《检验检测机构资质认定能力评价检验检测机构通用要求》(RB/T 214—2017)4.5.15中鼓励检验检测机构在检验检测出现临界值、内部质量控制或客户有要求时,报告测量不确定度。按《食品安全国家标准食品中总砷及无机砷的测定》(GB 5009.11... 详细信息

《检验检测机构资质认定能力评价检验检测机构通用要求》(RB/T 214—2017)4.5.15中鼓励检验检测机构在检验检测出现临界值、内部质量控制或客户有要求时,报告测量不确定度。按《食品安全国家标准食品中总砷及无机砷的测定》(GB 5009.11—2014)第二法原子荧光光谱法测定内部质控样芹菜中的总砷,并对其进行测量不确定度评定。结果显示芹菜中总砷的含量为0.516 mg·kg^(-1),其扩展不确定度为0.046 mg·kg^(-1),证书提供的标准差为0.021 mg·kg^(-1),换算成Z比分数,|Z|=0.33,测试结果满意。

关键词：原子荧光光谱法不确定度总砷含量芹菜

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Interfacial space charge characteristic of PPLP insulation for HVDC cables

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High Voltage 2020年第5期5卷 628-635页

作者： xuefeng zhao Lu Pu Zhiqiang Xu George Chen Wei Duan Haofei Sun Zeli Ju Shannxi Electric Power Research Institute Xi'anShannxiPeople's Republic of China School of Electronics and Computer Science University of SouthamptonSouthamptonUK

High-voltage DC(HVDC)cables show more efficiency than high-voltage AC cables over the long distance power transmission and have attracted significant attention recently due to rapid developments in off-shore wind farm.Polypropylene laminated paper(PPLP)insulation based HVDC cables have provided a reliable operation for many years and are the highest voltage level in operation at the moment.In this study,the authors intend to understand the electrical performance of PPLP insulation system by examining space charge in detail,especially at the interfaces.It has been found that the interface between polypropylene and Kraft paper acts as trap for charge carriers,resulting in an optimal electric field distribution in PPLP insulation system.The optimal electric field distribution enhances overall electrical performance of PPLP insulation,including higher dc breakdown strength and lower electrical conductivity.

关键词： PPLP insulation charge

基于双磁盘刀具钝化中磁弹磨粒的磨损及寿命研究

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组合机床与自动化加工技术 2024年第4期 26-30页

作者：吴泓辛赵雪峰刘漂贵州大学机械工程学院贵阳550025

为了探究磁弹磨粒在双磁盘刀具钝化中磨损规律以及使用寿命的长短,通过对磁弹磨粒进行受力分析讨论了其磨损失效的形式,得出了影响磁弹磨粒寿命的主要因素。然后,制备出不同质量配比和不同磨粒相类型的磁弹磨粒,采用双磁盘钝化设备进行... 详细信息

为了探究磁弹磨粒在双磁盘刀具钝化中磨损规律以及使用寿命的长短,通过对磁弹磨粒进行受力分析讨论了其磨损失效的形式,得出了影响磁弹磨粒寿命的主要因素。然后,制备出不同质量配比和不同磨粒相类型的磁弹磨粒,采用双磁盘钝化设备进行钝化实验,分析了磁弹磨粒质量配比和磨粒相类型对磁弹磨粒的磨损规律和对刃口表面粗糙度的变化规律,同时还对钝化前后的磁弹磨粒进行X射线能量色散普(EDS)和激光粒度分析。实验结果表明,以氧化铝为磨粒相的磁弹磨粒在钝化过程中主要发生磨粒相磨钝磨损,以金刚石为磨粒相的磁弹磨粒主要发生磨粒相脱落磨损,两种类型的磁弹磨粒都是在质量配比3:1时使用寿命最好。

关键词：刀具钝化磁弹磨粒磨粒磨损磨粒寿命

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