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Influence of the GEO satellite orbit error fluctuation correction on the BDS WADS zone correction

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Satellite Navigation 2020年第1期1卷 198-205页

作者： binghao wang Jianhua Zhou bin wang Dianwei Cong Hui Zhang Beijing Navigation Center Beijing 100094China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Information Engineering University Zhengzhou 450052China National Defense University Joint Operations College Shijiazhuang 050001China

Decimeter-level service is provided by the BeiDou satellite navigation system wide area differential service(BDS WADS)for users who collect carrier phase ***,the fluctuations in Geostationary Earth Orbit(GEO)satellite orbit errors reduce the spatial correlation of orbit *** fluctuations not only decrease the accuracy and stability of zone correction service provided by BDS WADS,but also shorten its effective *** this paper,we proposed an algorithm to weaken the influence of GEO satellite orbit error fluctuations and verified the method using data from eight sparsely distributed *** results show that orbit errors can be stabilized using orbit fluctuation corrections,and the positioning precision and stability of the BDS WADS can be improved *** normal circumstances,the horizontal and vertical positioning accuracy of users within 1000 km from the center of the zone can reach 0.19 m and 0.34 ***,the effective range is *** positioning performance within 1800 km could reach 0.24 m and 0.38 m for the horizontal and vertical components,respectively.

关键词： Wide area differential service Decimeter-level service Zone correction GEO orbit error Effective range

Heinrich Hildebrand:A German Railway Engineer in Late Qing China

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Chinese Annals of History of Science and Technology 2018年第1期2卷 34-56页

作者： wang bin Institute for the History of Natural Sciences Chinese Academy of SciencesBeijing 100190China

German engineer Heinrich Hildebrand came to China as a spy in 1891,serving at the German Embassy in Beijing and collecting Chinese railway *** 1892,he began to work for Zhang Zhidong and participated in the construction of the Daye railway and Hanyang Iron Works,among other *** by Zhang Zhidong,he was appointed as counselor of the China Railway Company by Sheng *** Germany took Jiaozhou Bay in 1897,Hildebrand presided over the survey and construction of the Shandong *** served as its General Director and chief engineer for ten years,which was the most important period of his *** his identity switched from German spy in Zhang Zhidong’s staff to General Director of the Shandong Railway,his colonialist mentality gradually came to the fore,and he took a tough stance when dealing with Chinese officials and *** was highly appreciated by Zhang Zhidong and strongly opposed by Yuan *** engineers in early modern China played a dual role in the course of China’s *** the one hand,they promoted the cause of China’s modernization as professionals,and on the other hand,they often became spokesmen for and active agents of imperialism.

关键词： Heinrich Hildebrand German spy railway engineer Shandong Railway

Internal energy transfer phenomenon and light-emission properties of γ-LiAlO_2 phosphor doped with Mn^(2+)

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 678-683页

作者： Bai-bin wang Chi-Fen Chang Wein-Duo Yang Department of Chemical and Materials Engineering Kaohsiung University of Applied Sciences Electronics Testing Center

γ-LiAlO2 phosphor was synthesized using the cellulose-citric acid sol-gel method, and its light emission and energy transfer properties were investigated. Excitation and emission spectrum analysis revealed a decrease in intensity of the spectrum as the amount of Mn2＋ doping increased. Blasse＇s equation determined the maximum distance for energy transfer between Mn2＋ ions as 4.3142 nm. Dexter＇s theory verifies that the mechanism of energy transfer between Mn2＋ ions conforms to an electric dipole and electric quadrupole interaction.

关键词： phosphor energy transfer light emission sol-gel process doping

Enhanced proton conductivity of viscose-based membranes via ionic modification and dyeing processes for fuel cell applications

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Journal of Materiomics 2023年第3期9卷 587-600页

作者： Haoyu Wu Tianchi Zhou bin wang Jinli Qiao Flexible Functional Materials Institute Yancheng Institute of Technology1 Hope Avenue RoadYancheng224051China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Environmental Science and EngineeringDonghua University2999 Ren'min North RoadShanghai201620China Shanghai Engineering Research Center of Marine Renewable Energy Shanghai201306China Shanghai Institute of Pollution Control and Ecological Security Shanghai200092China

Proton exchange membranes(PEMs),which are crucial fuel cell parts,play an important role in the field of energy ***,the further development of conventional PEMs based on synthetic polymers is greatly limited by high energy consumption and difficult *** this work,we reported the fabrication of a novel viscose-based PEM via cationic modification and dyeing treatment with the reactive dyes ***-efficiency proton transmission channels can be constructed due to the for-mation of the complex internal three-dimensional network of the as-prepared viscose-based PEM.Hþconductivity(sHþ)and water uptake are intensively investigated by changing the cationic agents and KE-7B1,and the maximum sHþreaches 44.19 mS/cm at 80℃and 98%relative humidity(RH).Furthermore,the prepared membrane shows the lowest calculated activation energy value(12.25 kJ/mol),indicating that both Grotthuss and Vehicle mechanisms play an important role in ionic *** membrane chemical structure and micromorphology are analyzed and the proton transmission modes are explored in detail,supplemented with research on the hydrophilic/hydrophobic characteristics and crystallinity of the *** application stability of the membranes is also evaluated analyzing the thermal,mechanical,and oxygen resistance properties,and the results show that all the prepared membranes can maintain good thermal stability within 200℃.The maximum tensile strength reaches 42.12 MPa,and the mass losses of the membranes soaked in 30%(in mass,same below)H_(2)O_(2)solution for 120 h can be restricted to 10%.Therefore,as a novel PEM,the obtained dye viscose-based membranes show great potential for application in fuel cells.

关键词： Membrane Viscose Reactive dyes Proton conductivity Fuel cell

SYNTHESIS AND CHARACTERIZATION OF FUNCTIONALIZED CARBON BLACK/POLY(VINYL ALCOHOL) HIGH REFRACTIVE INDEX NANOCOMPOSITES

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Chinese Journal of Polymer Science 2012年第5期30卷 652-663页

作者： Peng-fei Xue Ji-bin wang Yu-bin Bao 李秋影 Chi-fei Wu Polymer Alloy Laboratory and Key Laboratory of Ultrafine Materials of Ministry of Education East China University of Science and TechnologyShanghai200237China Shanghai Key Laboratory Polymeric Materials East China University of Science and TechnologyShanghai200237China

Carbon black （CB）/polymer composites with high refractive index （RI） were fabricated from poly（vinyl alcohol）（PVA） and covalently functionalized nano-CB （PVA-es-CB） by simple esterification reaction. Transmission electron microscopy showed that tmifonn aggregates of PVA-es-CB nanoparticles with a size smaller than I00 nm formed in the nanocomposite films. Ellipsometric measurements indicated that the PVA-es-CB/PVA composite films had a RI in the range 1.520-1.598 linearly increased with the PVA-es-CB volume content. Theoretical equation based on Lorentz-Lorenz theory provided reasonably close estimation of the refractive indices to the experimentally observed values. The hybrid films also revealed relatively good surface planarity, thermal stability and optical transparency.

关键词： High refractive index Carbon black Poly(vinyl alcohol) Nanocomposite.

The r-mode instability windows of strange stars

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Research in Astronomy and Astrophysics 2019年第2期19卷 161-168页

作者： Yu-bin wang Xia Zhou Na wang Xiong-Wei Liu Physics and Space Science College China West Normal University Xinjiang Astronomical Observatory Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences

With the constraint from gravitational wave emission of a binary merger system(GW170817)and two-solar-mass pulsar observations, we investigate the r-mode instability windows of strange stars with unpaired and color-flavor-locked phase strange quark matter. Shear viscosities due to surface rubbing and electron-electron scattering are taken into account in this work. The results show that the effects of the equation of state of unpaired strange quark matter are only dominant at low temperature, but do not have significant effects on strange stars in the color-flavor-locked phase. A color-flavor-locked phase strange star,which is surrounded by an insulating nuclear crust, seems to be consistent with observational data of young pulsars. We find that an additional enhanced dissipation mechanisms might exist in SAX J1808.4–*** spinning young pulsar PSR J0537–6910 is a primary source for detecting gravitational waves from a rotating strange star, and young pulsars might be strange stars with color-flavor-locked phase strange quark matter.

关键词： stars:neutron equation of state stars:oscillations

Slope failure simulations with MPM

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Journal of Hydrodynamics 2017年第3期29卷 445-451页

作者： Philip J.Vardon bin wang Michael A.Hicks Geo-Engineering Section Faculty of Civil Engineering and GeosciencesDelft University of Technology State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of Sciences

The simulation of slope failures,including both failure initiation and development,has been modelled using the material point method（MPM）.Numerical case studies involving various slope angles,heterogeneity and rainfall infiltration are *** is demonstrated that,by utilising a constitutive model which encompasses,in a simplified manner,both pre-and post-failure behaviour,the material point method is able to simulate commonly observed failure *** is a step towards being able to better quantify slope failure consequence and risk.

关键词： Heterogeneity material point method(MPM) rainfall-induced slope failure strain softening

Rainfall-runoff modeling for storm events in a coastal forest catchmen t using neural networks

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成都理工大学学报（自然科学版） 2008年第1期35卷 68-73页

作者： wang Yi HE bin United Graduate School of Agricultural Sciences Ehime University Japan

The process of transformation of rainfall into runoff over a catchment is very complex and highly nonlinear and exhibits both tempor al and spatial variabilities. In this article, a rainfall-runoff model using th e artificial neural networks (ANN) is proposed for simula ting the runoff in storm events. The study uses the data from a coa stal forest catchment located in Seto Inland Sea, Japan. This article studies the accuracy of the short-term rainfall forecast obta ined by ANN time-series analysis techniques and using antecedent rainfa ll depths and stream flow as the input information. The verification results from the proposed model indicate that the approach of ANN rai nfall-runoff model presented in this paper shows a reasonable agreement in rainfall-runoff modeling with high accuracy.

关键词：降雨径流模型暴风雨沿海林集水神经网络

Peculiar　Temporal　Structure　of　the　South　China　Sea　Summer　Monsoon

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Advances in Atmospheric Sciences 1997年第2期14卷 54-71页

作者： bin wang Renguang Wu Department of Meteorology University of Hawaii

Beijing located at the junction of four major components of the Asian-Australia monsoon system (the Indian, the western North Pacific, the East Asian subtropical, and the Indonesian-Australian monsoons), the monsoon climate over the South China Sea (SCS) exhibits some unique features. Evidences are presented in this paper to reveal and document the following distinctive features in the temporal structure of the SCS summer monsoon: (1) pronounced monsoon singularities in the lower tropospheric monsoon flows which include the pre-onset and withdrawal easterly surges and the southwesterly monsoon bursts at Julian pentad 34-35 (June 15-24) and pentad 46-47 (August 14-23); (2) four prominent subseasonal cycles (alternative occurrences of climatological active and break monsoons); (3) considerably larger year-to-year variations in convective activity on intraseasonal time scale compared to those over the Bay of Bengal and the Philippine Sea; (4) the redness of the climatological mean spectrum of precipitation/deep convection on synoptic to intraseasonal time scales in the central SCS; (5) a remarkable asymmetry in the seasonal transitions between summer and winter monsoons and an extremely abrupt mid-May transition (the outburst of monsoon rain and the sudden switch in the lower troposphere winds from an easterly to a westerly regime); (6) the bi-modal interannual variation of summer monsoon onset (normal and delayed modes). In addition, the monsoon rainfall displays enormous east-west gradient over the central SCS. Possible causes for these features are discussed. A number of specific science questions concerning some of the peculiar features are raised for the forthcoming SCS monsoon experiment to address.

关键词： Monsoon over SCS Subseasonal cycles, Spectrum of precipitation, Bi-modal interannual variation