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Journal of Central South University 2017年第6期24卷 1225-1232页

作者： liang ke Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China Faculty of Aerospace Engineering Delft University of TechnologyDelft 2629HSthe Netherlands

Efficient bolted joint design is an essential part of designing the minimum weight aerospace structures, since structural failures usually occur at connections and interface. A comprehensive numerical study of three-dimensional(3D) stress variations is prohibitively expensive for a large-scale structure where hundreds of bolts can be present. In this work, the hybrid composite-to-metal bolted connections used in the upper stage of European Ariane 5ME rocket are analyzed using the global-local finite element(FE) approach which involves an approximate analysis of the whole structure followed by a detailed analysis of a significantly smaller region of interest. We calculate the Tsai-Wu failure index and the margin of safety using the stresses obtained from ABAQUS. We find that the composite part of a hybrid bolted connection is prone to failure compared to the metal part. We determine the bolt preload based on the clamp-up load calculated using a maximum preload to make the composite part safe. We conclude that the unsuitable bolt preload may cause the failure of the composite part due to the high stress concentration in the vicinity of the bolt. The global-local analysis provides an efficient computational tool for enhancing 3D stress analysis in the highly loaded region.

关键词： bolted connection global-local finite element approach failure bolt preload

Interface characteristics and wear resistance of Ni-B_(4)C plated ZTA reinforced high chromium cast iron composite

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China Foundry 2023年第3期20卷 253-262页

作者： ke-liang Li Wei Li Yan-liang Yi Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou 510632China National Joint Engineering Research Center of High Performance Metal Wear Resistant Materials Technology Jinan UniversityGuangzhou 510632China

A chemical composite plating of Ni-B_(4)C was used to prepare the surface-modified zirconia toughened alumina(ZTA)ceramic *** ceramic preforms were prepared by the plated ZTA and sodium silicate solution binder,followed by casting infiltration to prepare the ZTA particles reinforced high chromium cast iron(HCCI)*** result reveals that a distinct interface layer forms at the ZTA/HCCI interface,which consists of phases of ZrB_(2),FeB,Fe_(2)B,and NaSiO_(4).The interfacial wettability between ZTA and HCCI is improved by the diffusion and reaction of Ni and B_(4)*** wear test reveals that the Ni-B_(4)C plated ZTA particles can effectively improve the wear resistance of the ZTA/HCCI composite,and the wear rate of the composite is decreased to 11.6%of HCCI.

关键词： ZTA composite high chromium cast iron interface layer three-body abrasive wear

A Class of Homogeneous Einstein Manifolds

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Chinese Annals of Mathematics,Series B 2006年第4期27卷 411-418页

作者： Yifang KANG ke liang Department of Mathematics Tianjin University Tianjin 300072 China School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 China.

A Riemannian manifold （M, g） is called Einstein manifold if its Ricci tensor satisfies r=c.g for some constant c. General existence results are hard to obtain, e.g., it is as yet unknown whether every compact manifold admits an Einstein metric. A natural approach is to impose additional homogeneous assumptions. M. Y. Wang and W. Ziller have got some results on compact homogeneous space G/H. They investigate standard homogeneous metrics, the metric induced by Killing form on G/H, and get some classification results. In this paper some more general homogeneous metrics on some homogeneous space G/H are studies, and a necessary and sufficient condition for this metric to be Einstein is given. The authors also give some examples of Einstein manifolds with non-standard homogeneous metrics.

关键词： Einstein manifold Homogeneous space General homogeneous metric

Sheets and rigid orbit covers of exceptional Lie groups

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Chinese Science Bulletin 1998年第20期43卷 1702-1707页

作者： ke liang Linyuan Lu Nankai Univ Dept Math Tianjin 300071 Peoples R China

All sheets of exceptional Lie groups by the geometric calculating method are given. The conjecture that the sheets of an exceptional Lie group are disjoint on the basis of the calculating result is proved.

关键词： Lie group orbit sheet.

Induced orbit data and induced unitary representations for complex groups

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Science China Mathematics 2014年第7期57卷 1435-1442页

作者： ZHANG MingJing liang ke School of Mathematical Sciences Nankai University The key Laboratory of Pure Mathematics and Combinatorics Nankai University

We use induced orbit covers to define induced orbit *** studying the space of regular functions on orbit cover,we know that the induced representation has close connection with the induced orbit datum under the meanin... 详细信息

关键词： Vogan’s conjecture on quantization induced orbit covers induced orbit data unitary representations

Dependence of low redshift Type Ia Supernovae luminosities on host galaxies

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Research in Astronomy and Astrophysics 2013年第9期13卷 1087-1096页

作者： Wen-ke liang Jian-Cheng Wang National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

We study the relation between Type Ia Supernovae （SNe Ia） and properties of their host galaxies using a large sample with low redshift. By examining the Hubble residuals of the entire sample from the best-fit cosmology, we show that SNe Ia in passive hosts are brighter than those in star-forming hosts after light curve correction at the 2. 1σ confidence level. We find that SNe Ia in high luminosity hosts are brighter after light-curve correction at the 〉 3σ confidence level. We also find that SNe Ia in large galaxies are brighter after light-curve correction at the ≥2σ confidence level. We demonstrate that the residuals depend linearly on host luminosity at a confidence of 4or or host size at a confidence of 3.3σ.

关键词： supernovae: general -- distance scale -- galaxies: classification

Homogeneous manifolds admitting non-Riemannian Einstein-Randers metrics

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Science China Mathematics 2015年第7期58卷 1473-1482页

作者： CHEN ZhiQi DENG ShaoQiang liang ke School of Mathematical Sciences and LPMC Nankai University

In this paper, we find some new homogeneous manifolds G/H admitting non-Riemannian EinsteinRanders metrics when G is the compact simple Lie group E6, or E7 or E8. In the beginning, we prove that these homogeneous manifolds admit Riemannian Einstein metrics. Based on these metrics, we obtain non-Riemannian Einstein Randers metrics on them.

关键词： Einstein metrics Randers metrics homogeneous manifolds

A modified Tikhonov regularization method for a Cauchy problem of a time fractional diffusion equation

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Applied Mathematics(A Journal of Chinese Universities) 2019年第3期34卷 284-308页

作者： CHENG Xiao-liang YUAN Le-le liang ke-wei School of Mathematical Sciences Zhejiang University

In this paper,we consider a Cauchy problem of the time fractional diffusion equation(TFDE)in x∈[0,L].This problem is ubiquitous in science and engineering *** illposedness of the Cauchy problem is explained by its solution in frequency ***,the problem is formulated into a minimization problem with a modified Tikhonov regularization *** gradient of the regularization functional based on an adjoint problem is deduced and the standard conjugate gradient method is presented for solving the minimization *** error estimates for the regularized solutions are obtained under Hp norm priori bound ***,numerical examples illustrate the effectiveness of the proposed method.

关键词： Cauchy problem time-fractional diffusion equation a modified Tikhonov regularization method conjugate gradient method error estimates

Locations of Sonic Points in Advection Dominated Accretion Flows Around Black Holes

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Chinese Physics Letters 1999年第4期16卷 310-312页

作者： YUAN Feng HUANG ke-liang Department of Astronomy Nanjing UniversityNanjing 210093 Department of Physics Nanjing Normal UniversityNanjing 210097

The global transonic solutions describing advection dominated accretion flows around black holes are obtained by directly integrating the set of differential equations from the sonic point inward to the horizon and *** results show that the sonic points can locate themselves at almost any radius,regardless of the viscous parameter a and polytropic indexγ.This result is greatly different with previous *** solutions with very different values of R_(s)from 4.3 to 300R_(g) and withγ=1.5,5/3 are given *** consistency between this result and that in inviscid flows is emphasized.

关键词： flows integrating radius

Experimental study on cyclic deformation properties of saturated Fujian sand at different loading frequencies

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Underground Space 2023年第6期13卷 150-165页

作者： Chong Yue ke liang Chengshun Xu Xiuli Du key Laboratory of Urban Security and Disaster Engineering of the Ministry of Education Beijing University of TechnologyBeijing 100124China

In this study,a series of undrained cyclic torsional shear tests were conducted to investigate the effect of cyclic loading frequency f on the pre-liquefaction(shearing contractive(SC)period and initial shearing dilative(ISD)period)and post-liquefaction(late shearing dilative(LSD)period)deformation properties of saturated Fujian *** secant shear modulus G and damping ratioλin the entire cyclic loading process,and the unloading tangent shear modulus G_(L1)and flow deformation tangent shear modulus GL2 in the ISD and LSD periods were adopted to quantitatively characterize the evolution of hysteresis loop with an increase in shear strain amplitude *** test results show that the effect of f on G of saturated Fujian sand in the SC period is not ***,all the G-γ_(a),G_(L1)-γ_(a),and GL2-ca curves in the ISD and LSD periods showed a downward trend with an increase in *** study also proposes a modified method for calculatingλto compensate for the analytical error caused by the non-closure of hysteresis *** with the classical curves that mainly applied in geotechnical engineering,theλfirst increases and then decreases with the increase ofγ***,theλevaluated by the modified method is approximately 10%–15%more than theλevaluated by the traditional method when theλreaches its peak value.

关键词： Sand liquefaction Cyclic loading frequency Hysteresis loop shape Shear modulus Damping ratio