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China Ocean Engineering 2021年第1期35卷 12-25页

作者： XIE Ming-xiao LI Shan ZHANG Chi yang zhi-wen HOU zhi-qiang ZHANG Huaqing Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringM.O.T.Tianjin 300456China CCCC First Harbor Engineering Co.Ltd. Tianjin 300461China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China

A well-established 3D phase-averaged beach morphodynamic model was applied to investigate the morphodynamics of a typical artificial beach,and a series of discussions were made on the surfzone hydro-sedimentological processes under calm and storm *** results revealed that the nearshore wave-induced current presents a significant 3D structure under stormy waves,where the undertow and longshore currents exist simultaneously,forming a spirallike circulation system in the *** longshore sediment transport would shorten the sediment supply in the cross-shore direction,subsequently suppress the formation of sandbars,showing that a typical recovery profile under calm waves does not necessarily develop,but with a competing process of onshore drift,undertow and longshore *** transport rate during storms reaches several hundreds of times as those under calm waves,and two storm events contribute approximately 60%to the beach *** transport pattern under calm waves is mainly bed load,but as the fine sands underneath begin to expose,the contribution of suspended load becomes significant.

关键词： beach evolution phase-averaged model wave-induced current storm surge morphodynamics

Asymptotic normality of error density estimator in stationary and explosive autoregressive models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 140-158页

作者： WU Shi-peng yang wen-zhi GAO Min HU Shu-he School of Mathematical Sciences&School of Big Data and Statistics Anhui UniversityHefei 230601China School of Statistics Shanxi University of Finance and EconomicsTaiyuan030006China

In this paper,we consider the limit distribution of the error density function estima-tor in the rst-order autoregressive models with negatively associated and positively associated random *** mild regularity assumptions,some asymptotic normality results of the residual density estimator are obtained when the autoregressive models are stationary process and explosive *** order to illustrate these results,some simulations such as con dence intervals and mean integrated square errors are provided in this *** shows that the residual density estimator can replace the density\estimator"which contains errors.

关键词： explosive autoregressive models residual density estimator asymptotic distribution association sequence

The CUSUM statistic of change point under NA sequences

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Applied Mathematics(A Journal of Chinese Universities) 2021年第4期36卷 512-520页

作者： LING Jin LI Xiao-qin yang wen-zhi JIAO Jian-ling School of Management Hefei University of TechnologyHefei 230009China Center for Applied Mathematics School of Mathematical SciencesAnhui UniversityHefei 230061China

In this paper,we investigate the CUSUM statistic of change point under the neg-atively associated(NA)*** establishing the consistency estimators for mean and covariance functions respectively,the limit distribution of the CUSUM statistic is proved to be a standard Brownian bridge,which extends the results obtained under the case of an indepen-dent normal sample and the moving average ***,the finite sample properties of the CUSUM statistic are given to show the efficiency of the method by simulation studies and an application on a real data analysis.

关键词： CUSUM statistic limit distribution NA sequences Brownian bridge

Some new results for demimartingales

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Applied Mathematics(A Journal of Chinese Universities) 2011年第1期26卷 14-22页

作者： WANG Xue-jun HU Shu-he yang wen-zhi SHEN Yan chool of Mathematical Science Anhui University Hefei 230039 China

Harremoes obtained some new maximal inequalities for non-negative martingales. In this paper, we get some new maximal and minimal inequalities for non-negative demimartin- gales which generalize the results of Harremoes. We also obtain an inequality for non-negative demimartingales which generalizes the result of Iksanov and Marynych. Finally we obtain a strong law of large numbers, strong growth rate and integrability of supremum for demimartin- gales which generalize and improve the result of Chow.

关键词： Maximal inequality minimal inequality demimartingale strong law of large numbers.

Experimental Study on Hydrodynamic Load Characteristics for A Typical Cross-Section of A Submerged Floating Tunnel

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China Ocean Engineering 2024年第5期38卷 893-903页

作者： ZHANG Hong-qian yang zhi-wen LI Shao-wu YUAN Chun-guang ZHANG Hua-qing National Engineering Research Center for Port Hydraulic Construction Technology Tianjin UniversityTianjin 300072China National Engineering Research Center for Port Hydraulic Construction Technology Tianjin Research Institute for Water Transport EngineeringM.O.T.Tianjin 300072China

The typical cross-sectional form of a submerged floating tunnel plays a significant role in the dynamic response of the tunnel itself,which directly affects the overall *** this work,a series of experiments involving wave action on a submerged floating tube cross section is reported to study its hydrodynamic load *** typical cross section tube cylinders,circular and rectangular,are *** are carried out in a wave flume with waves of relatively low Keulegan-Carpenter(KC)*** relative depths of submergence of 0,0.25 and 0.5 are *** measured wave forces in regular waves are used to analyze the horizontal force,vertical force and torque,and then the drag coefficient(Cd)and inertia coefficient(Cm)are *** results show that the drag coefficients at low KC numbers are large and decrease sharply with increasing KC *** inertial coefficient Cm values in the vertical direction are about 70%larger than those in the horizontal *** an increase in aspect ratio(the ratio of the height to width of the structure),the ratio of inertia coefficient in the horizontal direction to that in the vertical direction increases *** inertia force coefficient is very sensitive to the submerged water depth and aspect *** existing results may overestimate the actual force value.

关键词： submerged floating tunnel tube cylinder wave force coefficient physical experiments

Profiling and identification of chemical components of Shenshao Tablet and its absorbed components in rats by comprehensive HPLC/DAD/ESI-MS^n analysis

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Chinese Journal of Natural Medicines 2018年第10期16卷 791-800页

作者： MIAO wen-Juan HU Ying JIA Li ZHANG Chun-Xia yang wen-zhi ZHANG Ping GUO De-An Department of Pharmacy Institute of Hematology and Blood Disease HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300020China Tianjin State Key Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 300193China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China

Shenshao Tablet(SST),prepared from Paeoniae Radix Alba(PRA)and total ginsenoside of Ginseng Stems and Leaves(GSL),is a traditional Chinese medicine(TCM)preparation prescribed to treat coronary heart ***,its chemical composition and the components that can migrate into blood potentially exerting the therapeutic effects have rarely been *** developed an HPLC/DAD/ESI-MS^n approach aiming to comprehensively profile and identify both the chemical components of SST and its absorbed ingredients(and metabolites)in rat plasma and *** separation was performed on an Agilent Eclipse XDB C_(18) column using acetonitrile/0.1% formic acid as the mobile *** detection was conducted in both negative and positive ESI modes to yield more structure *** with reference compounds(t_R,MS^n),interpretation of the fragmentation pathways,and searching of in-house database,were utilized for more reliable structure elucidation.A total of 82 components,including 21monoterpene glycosides,four galloyl glucoses,two phenols from PRA,and 55 ginsenosides from GSL,were identified or tentatively characterized from the 70% ethanolic extract of *** them,seven and 24 prototype compounds could be detectable in the plasma and urine samples,respectively,after oral administration of an SST extract(4 g×kg^(–1))in *** metabolites were observed in the rat *** findings of this work first unveiled the chemical complexity of SST and its absorbed components,which would be beneficial to understanding the therapeutic basis and quality control of SST.

关键词： Shenshao Tablet Paeoniae Radix Alba Total ginsenoside of Ginseng Stems and Leaves Chemical component

Numerical Modeling of the Undertow Structure and Sandbar Migration in the Surfzone

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China Ocean Engineering 2017年第5期31卷 549-558页

作者： XIE Ming-xiao ZHANG Chi yang zhi-wen LI Shan LI Xin GUO Wei-jun ZUO Shu-hua Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringM.O.T. National Engineering Laboratory for Port Hydraulic Construction Technology Tianjin Research Institute for Water Transport EngineeringM.O.T. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Key Laboratory of Coastal Engineering Hydrodynamics of CCCC Tianjin Port Engineering InstituteCCCC College of Environmental Sciences and Engineering Dalian Maritime University

A process-based 3D numerical model for surfzone hydrodynamics and beach evolution was established. Comparisons between the experimental data and model results proved that the model could effectively describe the hydrodynamics, sediment transport feature and sandbar migration process in the surfzone with satisfactory precision. A series of numerical simulations on the wave breaking and shoaling up to a barred beach were carried out based on the model system. Analyzed from the model results, the wave-induced current system in the surfzone consists of two major processes, which are the phase-averaged undertow caused by wave breaking and the net drift caused by both of the nonlinear wave motion and surface roller effect. When storm waves come to the barred beach, the strong offshore undertow along the beach suppresses the onshore net drift, making the initial sandbar migrate to the seaside. Under the condition of calm wave environment, both the undertow and net drift flow to the shoreline at the offshore side of the sandbar, and then push the initial sandbar to the shoreline. The consideration of surface roller has significant impact on the modeling results of the sandbar migration. As the roller transfer rate increases, the sandbar moves onshore especially under the storm wave condition.

关键词： process-based numerical model undertow net driit sediment wansport sandbar migration

Elucidation of the fragmentation pathways of a complex 3,7-O-glycosyl flavonol by CID, HCD, and PQD on an LTQ-Orbitrap Velos Pro hybrid mass spectrometer

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Chinese Journal of Natural Medicines 2015年第11期13卷 867-872页

作者： yang wen-zhi WU Wan-Ying yang Min GUO De-An Shanghai Research Center for Modernization of Traditional Chinese Medicine National Engineering Laboratory for TCM Standardization Technology Shanghai Institute of Materia Medica Chinese Academy of Sciences

The present study was designed to systematically investigate the ESI-MSn behavior of a complex 3, 7-O-glycosyl flavonol, kaempferol 3-O-α-L-[2,3-di-O-β-D-（6-E-p-coumaroyl）glucopyranosyl]-rhamnopyranosyl-7-O-α-L-rhamnopyranoside （KO） isolated from Epimedium wushanense, and to address the elimination priority among different glycosylation sites and different sugars/substituents. The direct-infusion ESI-MSn experiment of KO was performed on a hybrid LTQ-Orbitrap Velos Pro mass spectrometer in both negative and positive ion modes by three different fragmentation mechanisms （CID, HCD, and PQD）. The CID, HCD, and PQD analyses of KO exhibited remarkable discrimination in respect of the scan range, richness, and distribution of product ions through the entire spectra. KO experienced different fragmentation pathways between two ionization modes： the negative mode CID of KO eliminated the glycosyl portions （priority： 7-sugar 〉 3-substituent and terminal substituents 〉 inner sugar） and produced aglycone product ions at m/z 284.03/285.04; however, abundant sodium-adduct B32 together with subsequent ijX30 cleavages were found characteristic for the positive mode CID-MSn. The fragmentation pathways by CID for KO were proposed by analyzing the high accuracy ESI-MS＂ data. Complementary structural information of KO regarding the aglycone and glycosyl portions was obtained by analyzing the ESI-MSn data in both ionization modes. In conclusion, the LTQ-Orbitrap method facilitates highly reliable qualitative analysis of bioactive flavonoids with three alternative fragmentation modes.

关键词： Flavonol 3,7-O-glycoside LTQ-Orbitrap Fragmentation pathway

Hájek-Rényi-type Inequality for a Class of Random Variable Sequences and Its Applications

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Communications in Mathematical Research 2011年第1期27卷 6-16页

作者： WANG XUE-JUN SHEN YAN HU SHU-HE yang wen-zhi School of Mathematical Science Anhui University Hefei 230039

In this paper, we obtain the Hejek-Renyi-type inequality for a class of random variable sequences and give some applications for associated random variable sequences, strongly positive dependent stochastic sequences and martingale difference sequences which generalize and improve the results of Prakasa Rao and Soo published in Statist. Probab. Lett., 57（2002） and 78（2008）. Using this result, we get the integrability of supremum and the strong law of large numbers for a class of random variable sequences.

关键词： Hajek-Renyi-type inequality associated random variable sequence strongly positive dependent stochastic sequence martingale difference sequence

An Improved Coupling of Numerical and Physical Models for Simulating Wave Propagation

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China Ocean Engineering 2014年第1期28卷 1-16页

作者：阳志文柳淑学李金宣 State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Department of Mechanical Engineering Technical University of Denmark

An improved coupling of numerical and physical models for simulating 2D wave propagation is developed in this paper. In the proposed model, an unstructured finite element model （FEM） based Boussinesq equations is applied for the numerical wave simulation, and a 2D piston-type wavemaker is used for the physical wave generation. An innovative scheme combining fourth-order Lagrange interpolation and Runge-Kutta scheme is described for solving the coupling equation. A Transfer function modulation method is presented to minimize the errors induced from the hydrodynamic invalidity of the coupling model and/or the mechanical capability of the wavemaker in area where nonlinearities or dispersion predominate. The overall performance and applicability of the coupling model has been experimentally validated by accounting for both regular and irregular waves and varying bathymetry. Experimental results show that the proposed numerical scheme and transfer function modulation method are efficient for the data transfer from the numerical model to the physical model up to a deterministic level.

关键词： coupling numerical model physical model wave propagation transfer function modulation