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Ultrasound Imaging of Pipeline Crack Based on Composite Transducer Array

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 25-34页

作者： Shou-Peng Song ying-jie Ni Department of Instrument Science and Engineering School of Mechanical Engineering Jiangsu University

Cracks, especially small cracks are di cult to be detected in oil and gas transportation pipelines buried underground or covered with layers of material by using the traditional ultrasonic inspection techniques. Therefore, a new com?posite ultrasonic transducer array with three acoustic beam incidence modes is developed. The space model of the array is also established to obtain the defect reflection point location. And the crack ultrasound image is thus formed through a series of small cubical elements expanded around the point locations by using the projection of binariza?tion values extracted from the received ultrasonic echo signals. Laboratory experiments are performed on a pipeline sample with di erent types of cracks to verify the e ectiveness and performance of the proposed technique. From the image, the presence of small cracks can be clearly observed, in addition to the sizes and orientations of the cracks. The proposed technique can not only inspect common flaws, but also detect cracks with various orientations, which is helpful for defect evaluation in pipeline testing.

关键词： Composite transducer array Ultrasound imaging Crack NDT&E

Ti-Zr-Cu-Fe-Sn-Si-Ag-Ta bulk metallic glasses with good corrosion resistance as potential biomaterials

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Rare Metals 2020年第6期39卷 688-694页

作者： ying Liu Hao-jie Wang Shu-jie Pang Tao Zhang Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang UniversityBeijing 100191China School of Physics and Nuclear Energy Engineering Beihang UniversityBeijing 100191China Beijing Advanced Innovation Centre for Biomedical Engineering Beihang UniversityBeijing 100191China

Ti47Cu38-xZr7.5Fe2.5Sn2 Si1 Ag2 Tax(x=1-4;at%,the same below)bulk metallic glasses(BMGs)with good bio-corrosion resistance and mechanical properties were fabricated by copper mold *** diameter of the Ti-based BMGs with 1 at%-4 at%Ta was 3 *** Ta-incorporated Ti-based BMGs exhibit higher open current potential and parallel passive current density in comparison with those of Ti-6 Al-4 V alloy in 0.9 wt%NaCl and Hank’s solution,implying their good corrosion *** pitting corrosion potential of the Ti-based BMGs gradually increases up to about 1.25 V with Ta addition increasing up to 4 at%in 0.9 wt%NaCl *** the present Ti-based BMGs,the alloy bearing2 at%Ta exhibits the optimal integration of mechanical properties,including the compressive fracture strength exceeding 2000 MPa,relative low Young’s modulus of98 GPa,plastic strain of 3.4%and high hardness of *** Ta-bearing Ti-based bulk metallic glasses with integration of relative high GFA,good mechanical properties and high bio-corrosion resistance are beneficial for biomedical applications.

关键词： Ti-based alloy Bulk metallic glass Glass forming ability Bio-corrosion resistance Mechanical properties

Subseasonal and Synoptic Variabilities of Precipitation over the Yangtze River Basin in the Summer of 2020

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Advances in Atmospheric Sciences 2021年第12期38卷 2108-2124页

作者： Liudan ding Tim LI ying SUN Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjing 210044China International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHawaii 96822USA National Climate Center Beijing 100081China

Summer precipitation over the Yangtze River basin(YRB)in 2020 experienced a strong subseasonal and synoptic fluctuation in addition to contributing to an exceptionally large seasonal mean *** cause of this higher-frequency fluctuation is examined based on observational *** from the continuous northward movement of the climatological mei-yu rainband,the mei-yu rainbelt in the summer of 2020 experienced multiple northward and southward *** cause of the swings was attributed to the subseasonal variability of southerly winds to the south and northeasterly winds to the north of the *** addition,synoptic-scale variability,characterized by the eastward propagation of low-level cyclonic vorticity and precipitation anomalies,was also commonplace in the summer of *** the strengthening of both the subseasonal and synoptic variabilities in the summer of 2020 was attributed to the increase of the background mean moisture,the synoptic variability was greatly affected by the subseasonal rainfall *** a result,both the synoptic-scale and subseasonal variabilities contributed to the north-south swings of the *** large-scale modulations by both the seasonal mean and subseasonal anomalies provide insight regarding the optimization of issuing accurate,extended-range forecasts of extreme weather events.

关键词： Yangtze River precipitation synoptic and subseasonal variabilities meridional swings of a rainbelt large-scale modulation of high-frequency variability

Parametric resonance of axially functionally graded pipes conveying pulsating fluid

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 239-260页

作者： jie JING Xiaoye MAO Hu ding Liqun CHEN Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

Based on the generalized Hamilton's principle,the nonlinear governing equation of an axially functionally graded(AFG)pipe is *** non-trivial equilibrium configuration is superposed by the modal functions of a simply supported *** the direct multi-scale method,the response and stability boundary to the pulsating fluid velocity are solved analytically and verified by the differential quadrature element method(DQEM).The influence of Young's modulus gradient on the parametric resonance is investigated in the subcritical and supercritical *** general,the pipe in the supercritical region is more sensitive to the pulsating *** nonlinearity changes from hard to soft,and the non-trivial equilibrium configuration introduces more frequency components to the ***,the increasing Young's modulus gradient improves the critical pulsating flow velocity of the parametric resonance,and further enhances the stability of the *** addition,when the temperature increases along the axial direction,reducing the gradient parameter can enhance the response *** work further complements the theoretical analysis of pipes conveying pulsating fluid.

关键词： pipe conveying fluid axially functionally graded supercritical resonance multi-scale method parametric resonance

Heterogeneous Cu catalyst in organic transformations

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Nano Research 2022年第4期15卷 2810-2833页

作者： Ruixue Zhang Yan Chen Muhua ding jie Zhao Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China

Copper catalysis plays a crucial role in organic synthesis providing a wide spectrum of important transformations over *** in homogeneous copper catalysis has often relied on the appropriate modulation of coordinating ligands,whereas the development of the corresponding heterogeneous variant has relatively gained less *** this review,we aim to deliver a comprehensive summary of a number of seminal heterogenized Cu-catalyzed homogenous catalysis reported over the last *** scope of this review is classified by the type of transformations in which the catalyst’s preparation and activity including the relationship between structure and activity are *** this way,this review highlights the potential and synthetic perspectives of heterogeneous copper catalysis in both academic and industry.

关键词： copper heterogeneous catalysis organic reactions

Analysis of the Cellular Localization of Herpes Simplex Virus 1 Immediate-early Protein ICP22

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Virologica Sinica 2010年第3期25卷 158-167页

作者： Wei CUN jie CHEN ying ZHANG Long-ding LIU Qi-han LI Institute of Medical Biology Chinese Academy of Medical Sciences Peking Union Medical College Kunming 650118 China

Nuclear proteins often form punctiform structures, but the precise mechanism for this process is unknown. As a preliminary study, we investigated the aggregation of an HSV-1 immediate-early protein, infected-cell protein 22 （ICP22）, in the nucleus by observing the localization of ICP22-EGFP fusion protein Results showed that, in high-level expression conditions, ICP22-EGFP gradually concentrates in the nucleus, persists throughout the cell cycle without disaggregation even in the cell division phase, and is finally distributed to daughter cells. We subsequently constructed a mammalian cell expression system, which had tetracycline- dependent transcriptional regulators. Consequently, the location of ICP22-EGFP in the nucleus changed with distinct induction conditions. This suggests that the cellular location of ICP22 is also influenced by promoter regulation, in addition to its own structure. Our findings provide new clues for the investigation of transcriptional regulation of viral genes. In addition, the non-protease reporter system we constructed could be utilized to evaluate the role of intemal ribosome entry sites （IRES） on transcriptional regulation.

关键词： Herpes Simplex Virus 1 (HSV-1) ICP22 Transcriptional regulation Cellular localization Nuclear functional domain

AI预测天然染料在丝绸上的最佳染色工艺与色牢度研究

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丝绸 2025年第1期62卷 40-48页

作者：刘莹陈杰南宁师范大学美术与设计学院南宁530001 武汉大学物理科学与技术学院武汉430000

随着环境问题的日益严峻,为了提高实验效率、节约成本,推动可持续发展战略在染料与纺织品领域的应用,文章首先对天然染料染色的数据进行了收集与预处理,然后采用Xgboost集成学习算法构建AI模型并进行了模型训练与验证,评估了模型的有效... 详细信息

随着环境问题的日益严峻,为了提高实验效率、节约成本,推动可持续发展战略在染料与纺织品领域的应用,文章首先对天然染料染色的数据进行了收集与预处理,然后采用Xgboost集成学习算法构建AI模型并进行了模型训练与验证,评估了模型的有效性和预测精度。该模型实现了天然染料在丝绸上染色工艺与效果的高效模拟与预测,从而显著缩短了实验时间并降低了资源损耗。这一方法提高了研究效率和经济效益。研究表明,该模型在预测反应最佳酸碱度(pH值)、水洗色牢度(CFW)和摩擦色牢度(CFR)方面具有较高的准确率,在验证集中三者的预测准确率高达94.12%、93.75%、100%,在真实的测试集上分别拥有87.50%、94.12%、82.35%的准确率,同时具备有效性与可迁移性。集成学习的方法通过极小的部署成本和极短的耗时为天然染料染色性能的探索给出了极具价值的指导,也为AI机器学习与纺织染色的学科的交叉应用拓展了可能性。

关键词： AI预测 Xgboost 天然染料丝绸色牢度

Asymptotic Properties of the Maximum Likelihood Estimate in Generalized Linear Models with Stochastic Regressors

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1679-1686页

作者： jie Li ding Xi Ru CHEN School of Mathematics and Statistics Wuhan University Wuhan 430072 P. R. China Graduate School Chinese Academy of Sciences Beijing 100039 P. R. China

For generalized linear models （GLM）, in case the regressors are stochastic and have different distributions, the asymptotic properties of the maximum likelihood estimate （MLE） β^n of the parameters are studied. U... 详细信息

关键词： Generalized linear models Consistency Asymptotic normality

Improving neural sentence alignment with word translation

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Frontiers of Computer Science 2021年第1期15卷 81-90页

作者： ying ding Junhui LI Zhengxian GONG Guodong ZHOU School of Computer Science and Technology Soochow UniversitySuzhou 215006China

Sentence alignment is a basic task in natural lan-guage processing which aims to extract high-quality paral-lel sentences *** by the observation that aligned sentence pairs contain a larger number of aligned words than unaligned ones,we treat word translation as one of the most useful external *** this paper,we show how to explicitly integrate word translation into neural sentence ***,this paper proposes three cross-lingual encoders to incorporate word translation:1)Mixed Encoder that learns words and their translation annotation vectors over sequences where words and their translations are mixed alterma-tively;2)Factored Encoder that views word translations as fea-tures and encodes words and their translations by concatenating their embeddings;and 3)Gated Encoder that uses gate mechanism to selectively control the amount of word translations moving *** on NIST MT and Opensub-titles Chinese-English datasets on both non-monotonicity and monotonicity scenarios demonstrates that all the proposed encoders significantly improve sentence alignment performance.

关键词： sentence alignment word translation mixeden coder factored encoder gated encoder