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Feature extraction for latent fault detection and failure modes classification of board-level package under vibration loadings.

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Science China(Technological Sciences) 2015年第11期58卷 1905-1914页

作者： tang Wei JING bo HUANG YiFeng SHENG ZengJin Aeronautics and Astronautics Engineering College Air Force Engineering University

A feature extraction for latent fault detection and failure modes classification method of board-level package subjected to vibration loadings is presented for prognostics and health management(PHM) of electronics using adaptive spectrum kurtosis and kernel probability distance clustering. First, strain response data of electronic components is filtered by empirical mode decomposition(EMD) method based on maximum spectrum kurtosis(SK), and fault symptom vector is developed by computing and reconstructing the envelope spectrum. Second, nonlinear fault symptom data is mapped and clustered in sparse Hilbert space using Gaussian radial basis kernel probabilistic distance clustering method. Finally, the current state of board level package is estimated by computing the membership probability of its envelope spectrum. The experimental results demonstrated that the method can detect and classify the latent failure mode of board level package effectively before it happened.

关键词： board-level package vibration loading spectrum kurtosis kernel probabilistic distance clustering

Effect of vanadium carbide on commercial pure aluminum

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International Journal of Minerals,Metallurgy and Materials 2017年第7期24卷 833-841页

作者： Hua-ping Sun Jun Wu Tian tang bo Fan Zheng-hua tang School of Materials Science and Engineering Sichuan University Chengdu 610065 China

The effect of vanadium carbide（VC） on the grain size of commercial pure aluminum was experimentally investigated by varying the content of VC, the holding time, and casting temperature. The refining efficiencies of VC and Al5Ti1 B were also compared. The refined samples of commercial pure aluminum were examined using optical microscopy, scanning electron microscopy（SEM） and energy-dispersive spectroscopy（EDS）. The results suggest that VC is a good refiner of commercial pure aluminum. The addition of only 0.3wt% VC can decrease the grain size of aluminum to 102 μm, whereas the casting temperature and holding time have little effect on the grain size. The refining efficiency of VC is better than that of Al5Ti1 B. The VC particles in molten aluminum act as nuclei and the grain refinement of aluminum alloys by VC particles is achieved via heterogeneous nucleation.

关键词： grain refinement vanadium carbide heterogeneous nucleation aluminum

Helicobacter pylori tumor necrosis factor-α inducing protein promotes cytokine expression via nuclear factor-κB

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World Journal of Gastroenterology 2013年第3期19卷 399-403页

作者： Chun-Li tang bo Hao Guo-Xin Zhang Rui-Hua shi Wen-Fang Cheng Department of Gastroenterology the First Affiliated Hospital of Nanjing Medical University

AIM:To study the effects of Helicobacter pylori(H. pylori)tumor necrosis factor-α(TNF)inducing protein (Tip-α)on cytokine expression and its mechanism. METHODS:We cloned Tip-αfrom the *** strain 26695,transformed Escherichia coli with an expression plasmid,and then confirmed the expression product by Western *** different concentrations of Tip-αthat affected SGC7901 and GES-1 cells at different times,we assessed cytokine levels using enzyme-linked immunosorbent *** blocked SGC7901 cells with pyrrolidine dithiocarbamate(PDTC),a specific inhibitor of nuclear factorκB(NF-κB).We then detected interleukin(IL)-1βand TNF-αlevels in SGC7901 cells. RESULTS:Western blot analysis using an anti-Tip-α antibody revealed a 23-kDa protein,which indicated that recombinant Tip-αprotein was recombined *** levels of IL-1β,IL-8 and TNF-αwere sig-nificantly higher following Tip-αinterference,whether GES-1 cells or SGC-7901 cells were used(P<0.05).However,the levels of cytokines(including IL-1β,IL-8 and TNF-α)secreted by SGC-7901 cells were greater than those secreted by GES-1 cells following treatment with Tip-αat the same concentration and for the same duration(P<0.05).After blocking NF-κB with PDTC, the cells(GES-1 cells and SGC-7901 cells)underwent interference with Tip-α.We found that IL-1βand TNF-αlevels were significantly decreased compared to cells that only underwent Tip-αinterference(P<0.05). CONCLUSION:Tip-αplays an important role in cyto-kine expression through NF-κB.

关键词： Helicobacter pylori Tumor necrosis factor-α inducing protein Interleukin-1β Interleukin-8 Tumor necrosis factor-α Nuclear factor-κB

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小儿气管插管时七氟醚合适临床浓度的研究

四川医学 2011年第2期32卷 182-183页

作者：侯俊石波汤和青陈明全唐万英陈春三峡大学第一临床医学院麻醉科湖北宜昌443003

目的探讨小儿气管插管时七氟醚的合适浓度。方法择期小儿腹股沟斜疝或鞘膜积液手术30例。术前常规禁食禁饮。根择Dixon序贯法来确定气管插管的七氟醚浓度。在咽喉反射消失、下颌松弛、睫毛反射消失时由同一熟练的麻醉医生行气管插管。... 详细信息

目的探讨小儿气管插管时七氟醚的合适浓度。方法择期小儿腹股沟斜疝或鞘膜积液手术30例。术前常规禁食禁饮。根择Dixon序贯法来确定气管插管的七氟醚浓度。在咽喉反射消失、下颌松弛、睫毛反射消失时由同一熟练的麻醉医生行气管插管。结果气管插管时呼末七氟醚浓度的ED50为5%。结论在不用其他药物辅助时,小儿气管插管时适宜的七氟醚浓度为5%。

关键词：七氟醚小儿麻醉 ED50

ANISOTROPIC CROUZEIX-RAVIART TYPE NONCONFORMING FINITE ELEMENT METHODS TO VARIATIONAL INEQUALITY PROBLEM WITH DISPLACEMENT OBSTACLE

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Journal of Computational Mathematics 2015年第1期33卷 86-99页

作者： Dongyang shi Caixia Wang Qili tang School of Mathematics and Statistics Zhengzhou University Zhengzhou 450001 China School of Mathematics and Information Science North China University of Water Resources and Electric Power Zhengzhou 450045 China School of Mathematics and Statistics Henan University of Science and Technology Luoyang 471023 China

In this paper, anisotropic Crouzeix-Raviart type nonconforming finite element meth- ods are considered for solving the second order variational inequality with displacement obstacle. The convergence analysis is presented and the optimal order error estimates are obtained under the hypothesis of the finite length of the free boundary. Numerical results are provided to illustrate the correctness of theoretical analysis.

关键词： Crouzeix-Raviart type nonconforming finite elements Anisotropy Variationalinequality Displacement obstacle Optimal order error estimates.

Microbial Geochemical Characteristics of the Coalbed Methane in the shizhuangnan Block of Qinshui Basin, North China and their Geological Implications

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Acta Geologica Sinica(English Edition) 2019年第3期93卷 660-674页

作者： LI Yang shi Wei tang Shuheng School of Energy Resource China University of GeosciencesBeijing 100083China Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Enrichment Mechanism Ministry of EducationBeijing 100083China Key Laboratory of Strategy Evaluation for Shale Gas Ministry of Land and ResourcesBeijing 100083China

Methanogens and sulfate reducing bacteria were detected by the 16SrRNA sequencing of coalbed methane(CBM)co-produced water in the south of the Qinshui Basin,which is indicative of the presence of secondary biological gas in the south of this basin,in contradiction to the previous understanding of thermogenic *** work systematically collected water samples from the CBM wells in the shizhuangnan Block and analyzed the microbial geochemical characteristics from the aspects of water ions,hydrogen and oxygen isotopes,dissolved inorganic carbon and microbial *** is shown that the shizhuangnan Block has a nearly SN-trending monoclinic structure,and the elevation of coal seam decreases gradually from the east to *** of the water blocking effect of Sitou fault in the west,the precipitation flowed from the east to west,and gradually transited to stagnant flow *** concentration variation of some ions such as Na^+,K^+,Ca2^+,Mg2^+,Cl^-,HCO3^-and total dissolved solids(TDS)suggest the variation of redox condition in the coal reservoir *** 16SrDNA sequencing analysis of the collected water samples detected the presence of methanogens and sulfate reduction *** presence of methane production zone and sulfate methane transition zone(SMTZ)was *** effect of methanogens in the methane production zone leads to an increase in the methane concentration,resulting in a high gas content in the study *** the SMTZ,most methane is consumed by anaerobic oxidation due to high sulfate concentrations.

关键词： CBM co-produced water microbial geochemistry sulfate methane transition zone shizhuangnan Block

Superconvergence Analysis of Splitting Positive Definite Nonconforming Mixed Finite Element Method for Pseudo-hyperbolic Equations

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Acta Mathematicae Applicatae Sinica 2013年第4期29卷 843-854页

作者： Dong-yang shi Qi-li tang School of Mathematics and Statistics Zhengzhou University School of Mathematics and Statistics Henan University of Science and Technology

In this paper, a new splitting positive definite nonconforming mixed finite element method is proposed for pseudo-hyperbolic equations, in which a quasi-Wilson quadrilateral element is used for the flux p, and the bilinear element is used for u. Superconvergence results in ｜｜·｜｜div,h norm for p and optimal error estimates in L2 norm for u are derived for both semi-discrete and fully discrete schemes under almost uniform meshes.

关键词： pseudo-hyperbolic equations splitting positive definite nonconforming mixed finite element method,superclose superconvergence

PD-type iterative learning control for nonlinear time-delay system with external disturbance

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Journal of Systems Engineering and Electronics 2006年第3期17卷 600-605页

作者： Zhang Baolin tang Gongyou Zheng shi Coll. of Information Science and Engineering Ocean Univ. of China Qingdao 266071 P. R. China Dept. of Information and Mathematics Sciences China Jiliang Univ. Hangzhou 310018 P.R. China

The PD-type iterative learning control design of a class of affine nonlinear time-delay systems with external disturbances is considered. Sufficient conditions guaranteeing the convergence of the n-norm of the tracking error are derived. It is shown that the system outputs can be guaranteed to converge to desired trajectories in the absence of external disturbances and output measurement noises. And in the presence of state disturbances and measurement noises, the tracking error will be bounded uniformly. A numerical simulation example is presented to validate the effectiveness of the proposed scheme.

关键词： time-delay system nonlinear system iterative learning control convergence external disturbance.

Computational Simulation and Electrochemically Deposited Molecularly Imprinted Polymer-coated Carbon Glass Electrode for Triclosan Detection

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1252-1260页

作者： GAO bo tang Shan-Shan LIU Jun-bo JIN Rui-Fa College of Resources and Environment Jilin Agricultural UniversityChangchun 130118China College of Chemistry and Chemical Engineering Chifeng UniversityChifeng 024000China

Triclosan,a kind of multi-purpose biocide,was widely used household cleaning and personal care *** widespread use of triclosan has potential risk to the ecotype and human health due to its release into sediment,surface and ground water resources.A molecularly imprinted electrochemical sensor for triclosan detection in cosmetic emulsion was synthesized and *** order to determine the suitable monomer and evaluate the template-monomer geometry as well as the interaction energy in the template-monomer prepolymerization mixture,a computational study was *** found that the complex formed by hybrid monomers(triclosan(o-phenylenediamine-co-resorcinol))had more hydrogen bonds and larger binding energy than that by single kind of monomers(triclosan(o-phenylenediamine)2 and triclosan(resorcinol)2).Therefore,hybrid monomers were used to synthesize the imprinted electrochemical sensor,which exhibits a high sensitivity and selectivity for triclosan sensing with the detection range 0~15 ng·mL-1 and detection limit 0.41 ng·mL-1.

关键词： computational simulation electrochemical synthesis molecular imprinting triclosan hybrid monomers