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Green–Naghdi理论,B部分:深水波Green–Naghdi(GN)方程

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哈尔滨工程大学学报（英文版） 2023年第1期22卷 44-51页

作者：段事良赵彬彬 W.c.Webster college of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China civil&Environmental Engineering University of CaliforniaBerkeley CA94704USA

“Green–Naghdi Theory,Part A:Green–Naghdi(GN)Equations for Shallow Water Waves”have investigated the linear dispersion relations of high-level GN equations in shallow *** this study,the GN equations for deep water waves are *** the traditional GN equations for deep water waves,the velocity distribution assumption involves only one representative wave ***,a new velocity distribution shape function with multiple representative wave numbers is ***,we have derived the three-dimensional GN equations and analyzed the linear dispersion relations of the GN-3 and GN-5 *** this study,the finite difference method is used to simulate focus waves in the time ***,the GN-5 equations are used to validate the wave profile and horizontal velocity distribution along water depth for different focused waves.

关键词： Green–Naghdi equations Finite difference Water waves Deep water Focused waves

Longitudinal vibration of pile in layered soil based on Rayleigh-Love rod theory and fictitious soil-pile model

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Journal of central South University 2015年第5期22卷 1909-1918页

作者：吕述晖王奎华吴文兵 c.J.LEO Key Laboratory of Soft Soils and Geoenvironmental Engineering of Ministry of Education(Zhejiang University) Engineering Faculty China University of Geosciences School of computing Engineering and Mathematics University of Western SydneyLocked Bag 1797 Penrith Sydney NSW 2751 Australia

The dynamic response of pile in layered soil is theoretically investigated when considering the transverse inertia ***, the fictitious soil-pile model is employed to simulate the dynamic interaction between the pile and the soil layers beneath pile toe. The dynamic interactions of adjacent soil layers along the vertical direction are simplified as distributed Voigt ***, the pile and fictitious soil-pile are assumed to be viscoelastic Rayleigh-Love rods, and both the radial and vertical displacement continuity conditions at the soil-pile interface are taken into consideration. On this basis, the analytical solution for dynamic response at the pile head is derived in the frequency domain and the corresponding quasi-analytical solution in the time domain is then obtained by means of the convolution theorem. Following this, the accuracy and parameter value of the hypothetical boundaries for soil-layer interfaces are discussed. comparisons with published solution and measured data are carried out to verify the rationality of the present solution. Parametric analyses are further conducted by using the present solution to investigate the relationships between the transverse inertia effects and soil-pile parameters.

关键词： viscoelastic pile layered soil longitudinal vibration fictitious soil-pile transverse inertia effect

Electrochemical process of titanium extraction

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中国有色金属学会会刊：英文版 2007年第2期17卷 429-433页

作者： cH. RVS. NAGESH c. S. RAMAcHANDRAN Defence Metallurgical Research Laboratory HyderabadA.P. India-500058

A wide variety of processes are being pursued by researchers for cost effective extraction of titanium metal. Electrochemical processes are promising due to simplicity and being less capital intensive. Some of the promising electrochemical processes of titanium extraction were reviewed and the results of laboratory scale experiments on electrochemical reduction of TiO2 granules were brought out. Some of the kinetic parameters of the reduction process were discussed while presenting the quality improvements achieved in the experimentation.

关键词：钛萃取电化学还原过程动力学参数

Generation of a New coupled Ultra-Short Pulse System from a Group Theoretical Viewpoint: the cartan Ehresman connection

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chinese Physics Letters 2012年第2期29卷 5-8页

作者： Saliou Youssoufa Victor K.Kuetche Timoleon c.Kofane National Advanced School of Engineering University of Yaounde IP.O.Box 8390Cameroon Department of Physics Faculty of ScienceUniversity of Yaounde IP.O.Box 812Cameroon

Based upon the group theoretical jet bundle formalism introduced by Wahlquist and Estabrook for discussing the complete integrability of soliton systems,we investigate the prolongation structure of Wadati-Konno-Ichikawa isospectral evolution *** a result,we unearth a new physical coupled system entailing a hidden structural symmetry SL(3,R) arising in the description of ultra-short pulse propagation in optical nonlinear *** a matter of fact,we depict a graphical representation of one-breather and two-breather ultra-short pulses in motion with a non-zero angular *** extending the previous study to multidimensional symmetry SL(n,R),we unearth a more general class of multicomponent coupled nonlinear ultra-short pulse system with its associated inverse scattering formulation particularly useful in soliton theory.

关键词： theory soliton symmetry

Structural modeling of sandwich structures with lightweight cellular cores

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Acta Mechanica Sinica 2007年第5期23卷 545-559页

作者： T.Liu Z.c.Deng T.J.Lu Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China MOE Key Laboratory of Strength and Vibration School of AerospaceXi'an Jiaotong UniversityXi'an 710049China

An effective single layered finite element （FE） computational model is proposed to predict the structural behavior of lightweight sandwich panels having two dimensional （2D） prismatic or three dimensional （3D） truss cores. Three different types of cellular core topology are considered： pyramidal truss core （3D）, Kagome truss core （3D） and corrugated core （2D）, representing three kinds of material anisotropy： orthotropic, monoclinic and general anisotropic. A homogenization technique is developed to obtain the homogenized macroscopic stiffness properties of the cellular core. In comparison with the results obtained by using detailed FE model, the single layered computational model can give acceptable predictions for both the static and dynamic behaviors of orthotropic truss core sandwich panels. However, for non-orthotropic 3D truss cores, the predictions are not so well. For both static and dynamic behaviors of a 2D corrugated core sandwich panel, the predictions derived by the single layered computational model is generally acceptable when the size of the unit cell varies within a certain range, with the predictions for moderately strong or strong corrugated cores more accurate than those for weak cores.

关键词： cellular material Sandwich panel Homogenization Finite element

Effects of electric field on recrystallization texture evolution in cold-rolled high-purity aluminum sheet during annealing

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中国有色金属学会会刊：英文版 2007年第1期17卷 143-147页

作者：吴艳赵骧何长树赵志朋左良 c. ESLING Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern University LETAM CNRS-UMR 7078University of MetzIle du Saulcy

The effects of an external Dc(direct current)electric field on recrystallization texture evolution in the cold-rolled aluminum sheets with 99.99%purity were investigated by means of X-ray diffraction *** cold-rolled high-purity aluminum sheets were annealed for 60 min at 200,300 and 400℃,respectively with and without an external Dc electric field of 800 V/*** results show that with Dc electric field,the recrystallization cube texture is strengthened at the stage of grain growth. Possible reason for the strengthening of the recrystallization cube texture with the applied electric field may be attributed to both selected nucleation and selected growth of cube oriented crystal nuclei.

关键词：重结晶作用冷轧工艺铝形核

Identifying female phenotypes that promote behavioral isolation in a sexually dimorphic species of fish Etheostoma zonale

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current Zoology 2021年第2期67卷 225-236页

作者： Natalie S.ROBERTS Tamra c.MENDELSON Department of Biological Sciences University of Maryland Baltimore CountyBaltimoreMD21250USA

In sexually dimorphic species characterized by exaggerated male ornamentation,behavioral isola-tion is often attributed to female preferences for conspecific male ***,in a number of sexu-ally dimorphic species,male mate choice also results in behavioral *** many of these cases,the female traits that mediate species boundaries are *** in sexually dimorphic species typically lack many of the elaborate traits that are present in males and that are often used for taxonomic classification of *** a diverse and largely sexually dimorphic group of fishes called darters(Percidae:Etheostoma),male mate choice contributes to behavioral isolation be-tween a number of species;however,studies addressing which female traits males prefer are *** this study,we identified the dominant female pattern for two sympatric species,Etheostoma zonale and Etheostoma barrenense,using pattern energy analysis,and we used discriminate func-tion analysis to identify which aspects of female patterning can reliably classify *** then tested the role of female features in male mate choice for ***,by measuring male preference for computer animations displaying the identified(species specific)conspecific *** found that the region above the lateral line is important in mediating male mate preferences,with males spending a significantly greater proportion of time with animations exhibiting conspecific female patterning in this region than with animations exhibiting heterospecific female *** results suggest that the aspects of female phenotypes that are the target of male mate choice are different from the conspicuous male phenotypes that traditionally characterize species.

关键词： darters discriminant function analysis Etheostoma female phenotype male mate choice 3D animations

Upper Darriwilian(Middle Ordovician) Radiolarians and Ostracods from the Hulo Formation, Zhejiang Provicnce, South china

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Journal of Earth Science 2018年第4期29卷 886-899页

作者： Yuhao Yi Aihua Yuan Jonathan c Aitchison Qinglai Feng School of Earth Sciences China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences School of Earth and Environmental Sciences University of Queensland

considerable research has been done on the Ordovician marine fossils from South china, including macrofossils such as brachiopods, graptolites, bivalves, trilobites, some microfossils like conodonts and acritarches. However, radiolarians and ostracods that are also important consti- tuents of the Ordovician marine ecosystem have been paid little attention in this region. In this study, ten radiolarians species belonging to four genera and sixteen ostracods species grouped into nine genera were found from the Hulo Formation at the Hengdu Section of the Jiangshan District, west- ern Zhejiang Province, South china. The fossil-bearing strata belong to the graptolite Pterograptus elegans Zone which indicates the Late Darriwilian Age. This radiolarian fauna is the first record of the Middle Ordovician radiolarian body fossils and also the earliest Ordovician radiolarian fauna reported from South china. The occurrence of Beothuka in this fauna extends the stratigraphic range of the genus to the Upper Darriwilian. Reviews of previous literatures suggest that the diversity of Beothuka was greater during the Early Ordovician, and then declined gradually from the Early Ordovician to the Middle Ordovician before its extinction. The co-occurring ostracod fauna belongs to a shallow-water ecotype. This is contrary to the host lithofacies of the ostracod fauna which represent a deep-water environment. Therefore, these ostacods may have been transported from the shallow-water environment, most likely from the Yangtze carbonate platform. If this conjecture is the truth, then the Jiangshan District was near the shallow-water carbonate platform and received its sediments during the Darriwilian. It is still essential to do more work in the future to better understand the ecology of the Ordovician ostracod fanuas and their role in the sedimentary system of South china.

关键词： radiolarians ostracods ecotype Ordovician Hengdu Section South china.

Flash X-ray radiography technique to study the high velocity impact of soft projectile on E-glass/epoxy composite material

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Defence Technology（防务技术） 2019年第2期15卷 216-226页

作者： B.Venkata Ramudu c.Jayarami Reddy V.Madhu Armour Design and Development Division Defence Metallurgical Research Laboratory

In the present paper, the high velocity impact of 9 mm soft lead projectile on 10 mm and 30 mm thick Eglass/epoxy composites was studied using a 450 kV Flash X-ray radiography(FXR) system. The basic parameters of FXR imaging, such as effect of ratio of target to film(TF) and source to target(ST) distances and X-ray penetration thickness of the composite material were optimized based on clarity and the actual dimensions of the objects. The optimized parameters were used in the FXR imaging of the ballistic event of 9 mm soft projectile on E-glass/epoxy composite. The real time deformation patterns of both the projectile and composite target during the ballistic impact were captured and studied at different time intervals. The notable failure modes of the 10 mm thick target with time include fibre breakage, bulging on the back side, delamination, recovery of the bulging, reverse bulging and its recovery. However, with increase in thickness of the target to 30 mm the only failure mechanism observed is the breaking of fibres. The ballistic impact event was also numerically simulated using commercially available LS-DYNA software. The numerically simulated deformation patterns of the projectile and target at different time intervals are closely matching with the corresponding radiographic images.

关键词： Flash X-ray radiography E-Glass/epoxy composite Ballistic impact Numerical simulation