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System Identification Method for Evaluating the Effect of Thickness Error on Backcalculated Pavement Layer Moduli

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上海交通大学学报 2004年第z2期38卷 182-187页

作者： ZHONG Yan-hui WANG Fu-ming zhang Bei CAI Ying-chun Dalian University of Technology Dalian116024 P. R. China Zhengzhou University Zhengzhou450002 P. R. China Zhengzhou University Zhengzhou450002 P. R. China Zhengzhou University Zhengzhou450002 P. R. China Chonging University Chongqing400044 P. R. China Dalian University of Technology Dalian116024 P. R. China Zhengzhou University Zhengzhou450002 P. R. China

Based on system identification theory and FWD testing data, the effect of thickness error on backcalculating pavement layer moduli is studied and the method of singular value decomposition (SVD) is presented to solve the morbidity problem of sensitivity matrix in this *** results show that the thickness error has great effects on the backcalculated pavement layer moduli. The error of backcalculated moduli can be controlled within the range of ±15% by limiting the thickness error within the range of ±5%.

关键词： system identification singular value decomposition (SVD) backcalculation pavement falling weight deflectometer (FWD) moduli thickness

Cooperative Dynamics in Lattice-Embedded Scale-Free Networks

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Communications in Theoretical Physics 2009年第9期52卷 411-415页

作者： SHANG Li-hui zhang ming-Ji YANG Yan-Qing Department of Control Science and Engineering University of Shanghai for Science and Technology Shanghai 200093China

We investigate cooperative behaviors of lattice-embedded scale-free networking agents in the prisoner'sdilemma game model by employing two initial strategy distribution mechanisms,which are specific distribution to themost connected sites (hubs) and random *** study indicates that the game dynamics crucially dependson the underlying spatial network structure with different strategy distribution *** cooperators' specificdistribution contributes to an enhanced level of cooperation in the system compared with random one,and cooperationis robust to cooperators' specific distribution but fragile to defectors' specific ***,unlike the specificcase,increasing heterogeneity of network does not always favor the emergence of cooperation under random ***,we study the geographical effects and find that the graphically constrained network structure tends toimprove the evolution of cooperation in random case and in specific one for a large temptation to defect.

关键词： geographical networks prisoner's dilemma cooperation heterogeneity

Analysis of factors influencing the Henry Hub natural gas price based on factor analysis

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Petroleum Science 2017年第4期14卷 822-830页

作者： Hong Li hui-ming zhang Yuan-Tao Xie Di Wang School of Economics Peking UniversityBeijing 100871People's Republic of China Center for National Resource Economy Studies Beijing 100871People's Republic of China School of Insurance and Economics University of International Business and EconomicsBeijing 100029People's Republic of China

Henry Hub as an important transaction hub for natural gas sets the gas price standard in the USA. In this paper, the factors influencing Henry Hub natural gas prices are analyzed, and the major factors determining the price levels in the period between January 1997 and December 2016 are studied. It is found that economic conditions, total energy demand, US dollar exchange rate and gas consumption are the major factors. The mechanism of each factor influencing the Henry Hub natural gas price is also explored in the paper.

关键词： Natural gas Henry Hub Factor analysis

Study on fast calibration of a ULA's gain and phase error

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Journal of Marine Science and Application 2007年第2期6卷 64-69页

作者： ZHU Guang-ping SUN hui zhang ming-hui College of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001 China

Array calibration is important in engineering practice. In this paper, fast calibration methods for a ULA's gain and phase errors both in far and near fields are proposed. In the far field, using a single sound source without exact orientation, this method horizontally rotates the array exactly once, performs eigen value decomposition for the covariance matrix of received data, then computes the gain and phase error according to the formulas. In the near field, using the same single sound source, it is necessary to rotate the array horizontally at most three times, build equations according to geometric relations, then solve them. Using the formula proposed in this paper, spherical waves are modified into plane waves. Then eigen values decomposition is performed. These two calibration methods were shown to be valid by simulation and are fast, accurate and easy to use. Finally, an analysis of factors influencing estimation precision is given.

关键词： ULA single sound source gain and phase error eigen values decomposition

Estimation of OCDD degradation rate in soil

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Journal of Environmental Sciences 2005年第6期17卷 981-983页

作者： ZHAO Xing-ru ZHENG ming-hui zhang Bing QIAN Yong XU Xiao-bai State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of ScienceBeijing 100085 China

The current concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans （PCDD/Fs） were determined in soils contaminated with Chinese technical product sodium pentachlorophenate （ Na- PCP）. The estimated half-life of octachlorodioxin （OCDD） was about 14 years in contaminated soils based on the local historical record and mass balance calculation during the past 43 years（ 1960-2003）. The isomer profiles remained the same regardless of paddy field soil or riverbank soil. The results indicated that the congenerspecific information was efficient in estimating the PCDD/Fs fate in contaminated soils.

关键词： OCDD degradation rate Na-PCP

Intravitreal injection of resveratrol inhibits laser-induced murine choroidal neovascularization

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International Journal of Ophthalmology(English edition) 2020年第6期13卷 886-892页

作者： hui-ming zhang Xiao-Hua Li mingjiazi Chen Jing Luo Department of Dermatology the Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina Hunan Key Laboratory of Medical Epigenomics Changsha 410011Hunan ProvinceChina Department of Pathology and Ophthalmology Keck School of Medicine at University of Southern CaliforniaLos AngelesCalifornia 90033USA Henan Provincial People's Hospital/Henan Eye Hospital Henan Eye InstituteHenan Key Laboratory of Ophthalmology and Vision Science/Department of OphthalmologyPeople’s Hospital ofZhcngzliou University/Department of OphthalmologyPeople's Hospital of Henan UniversityZhengzhou 450003Henan ProvinceChina 5Department of Ophthalmologythe Second Xiangya I IospitalCentral South UniversityChangsha 410011Hunan ProvinceChina

AIM:To determine the effects of intravitreal resveratrol(RSV)on murine laser-induced choroidal neovascularization(CNV).METHODS:The toxicity of RSV to choroidal endothelial cell(CEC)was measured using thiazolyl blue tetrazolium bromide(M一)*** of RSV on choroidal endothelial cell(CEC)migration were evaluated with a modified Boyden chamber assay,while tube formation was evaluated in a 2-D gel *** was induced by laser photocoagulation in *** effects of intravitreal injection of RSV on CNV development were evaluated by fluorescein angiography(FA),confocal analysis of isolectin B4 labeled choroidal flat mounts,and histologic examination of CNV *** was used to analyze the expression and phosphorylation of vascular endothelial growth factor receptor 2(VEGFR2).RESULTS:No significant cell toxicity was observed in CEC if the concentration of RSV was less than 200 pmol/L(P>0.05).RSV inhibited vascular endothelial growth factor(VEGF)-induced CEC migration(P<0.05)and tube formation(P<0.05)***,intravitrealinjectionof RSV significantly inhibited laser induced CNV formation in *** FA leakage,CNV volume and CNV area analysis revealed that there were 41%,45%,and 58%reduction in RSV-treated eyes(1.691±0.1032,178163±78623μm^3 and 6508±619.0μm^2,respectively)compared with those in control(2.724±0.08447,379676±98382μm3and16576±2646μm^2,respectively;P<0.05).Phospho-VEGFR2expression was much weaker in the sections of CNV lesions in RSV injected mice compared with that in control(P<0.05).CONCLUSION:Intravitreal injection of RSV exerts an inhibitory effect on CNV,which may through suppressing endothelial cell migration,tube formation and VEGFR2 phosphorylation.

关键词： resveratrol intravitreal injection choroidal neovascularization vascular endothelial growth factor receptor 2 tube formation murine

Interaction of hispidin with pepsin:Multi-spectroscopic analyses and docking simulation

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Food and Health 2024年第1期6卷 21-27页

作者： Wen-Qiang Wang Si-Hua Fan Xin-Huai Zhao Li Wang ming-hui zhang Qiang zhang Xue-Jun Gao College of Biology and Food Engineering Guangdong University of Petrochemical TechnologyMaoming525000China College of Animal Science Yangtze UniversityJingzhou 434023China

Hispidin is a pyranone compound found in edible and medicinal mushrooms of the Phellinus and Inonotus *** investigation used fluorescence spectroscopy,UV absorption spectroscopy,and molecular docking to examine the interaction of hispidin with *** Stern-Volmer method was used to perform the fluorescence quenching measurements at different temperatures(298 K,303 K,and 310 K).According to the findings,hispidin induced a static quenching mechanism in pepsin that resulted in the creation of a hispidin-pepsin complex with binding constants(Ka)ranging from 9.56×10^(4) to 3.45×10^(5) L mol^(-1).The positive values ofΔH(84.6 kJ mol-1)andΔS(337.9 J mol^(-1) K^(-1))demonstrated that hydrophobic forces contributed to forming the hispidin-pepsin *** findings of UV-vis absorption,synchronous fluorescence,and 3D fluorescence spectraspectra demonstrated that hispidin altered the conformation and microenvironment of *** to the analysis of molecular docking,hispidin got into the pepsin's active *** research clarifies the molecular mechanisms by which hispidin binds to pepsin and helps understand its possible biological activity in vivo.

关键词： hispidin pepsin spectroscopy molecular docking

Analysis of spudcan-footprint interaction in a single soil with nonlinear FEM

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Petroleum Science 2015年第1期12卷 148-156页

作者： Dong-Feng Mao ming-hui zhang Yang Yu Meng-Lan Duan Jun Zhao College of Mechanical and Transportation Engineering China University of Petroleum

The footprints that remain on the seabed after offshore jack-up platforms completed operations and moved out provide a significant risk for any futurej ack-up installation at that site. Detrimental horizontal and/or rotational loads will be induced on the base cone of the jack-up platform leg （spudcan） in the preloading process where only vertical loads are normally expected. However, there are no specific guidelines on design of spudcan re-installation very close to or partially overlapping existing footprints. This paper presents a rational design approach for assessing spudcan-footprint interaction and the failure process of foundation in a single layer based on nonlinear finite element method. The rela- tionship between the distance between the spudcan and the footprint and the horizontal sliding force has been obtained. Comparisons of simulation and experimental results show that the model in this paper can deal well with the combined problems of sliding friction contact, fluid-solid coupling, and convergence difficulty. The analytical results may be useful to jack-up installation workovers close to existing footprints.

关键词： Jack-up Existing footprint Spudcan-footprint interaction Numerical simulation Nonlinearity

Perturbation to Mei Symmetry and Adiabatic Invariants for Nonholonomic Systems in Terms of Quasi-Coordinates

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Communications in Theoretical Physics 2009年第11期52卷 779-783页

作者： PANG Ting FANG Jian-hui zhang ming-Jiang LIN Peng LU Kai College of Physics Science and Technology China University of Petroleum Dongying 257061 China

Abstract Based on the concept of adiabatic invariant, the perturbation to Mei symmetry and adiabatic invariants for nonholonomic mechanical systems in terms of quasi-coordinates are studied. The definition of the perturbation to Mei symmetry for the system is presented, and the criterion of the perturbation to Mei symmetry is given. Meanwhile, the Mei adiabatic invariants for the perturbed system are obtained.

关键词： Mei symmetry perturbation nonholonomic mechanical system quasi-coordinates