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Frontiers of Structural and Civil Engineering 2019年第1期13卷 92-102页

作者： Chung Nguyen VAN Department of Civil Engineering Faculty of EngineeringChulalongkorn UniversityThailand Faculty of Civil Engineering Ho Chi Minh City of Technology and EducationVietNam

The scaled boundary finite element method (SBFEM)is applied to the static analysis of two dimensional elasticity problem,boundary value problems domain with the domain completely described by a circular defining curve. The scaled boundary finite element equations is formulated within a general framework integrating the influence of the distributed body force,general boundary conditions,and bounded and unbounded *** paper investigates the possibility of using exact geometry to form the exact description of the circular defining curve and the standard finite element shape function to approximate the defining *** linear elasticity problems are presented to verify the proposed method with the analytical *** examples show the accuracy and efficiency of the proposed method,and the performance is found to be better than using standard linear element for the approximation defining curve on the scaled boundary method.

关键词： exact geometry circular defining curve general boundaries SBFEM

Efficient construction of a substitution box based on a Mordell elliptic curve over a finite field

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Frontiers of Information Technology & Electronic Engineering 2019年第10期20卷 1378-1389页

作者： Naveed Ahmed AZAM Umar HAYAT Ikram ULLAH Department of Applied Mathematics and Physics Graduate School of InformaticsKyoto UniversityKyoto 606-8501Japan Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan

Elliptic curve cryptography has been used in many security systems due to its small key size and high security compared with other cryptosystems. In many well-known security systems, a substitution box (S-box) is the only non-linear component. Recently, it has been shown that the security of a cryptosystem can be improved using dynamic S-boxes instead of a static S-box. This necessitates the construction of new secure S-boxes. We propose an efficient method to generate S-boxes that are based on a class of Mordell elliptic curves over prime fields and achieved by defining different total orders. The proposed scheme is devel-oped in such a way that for each input it outputs an S-box in linear time and constant space. Due to this property, our method takes less time and space than the existing S-box construction methods over elliptic curves. Computational results show that the pro-posed method is capable of generating cryptographically strong S-boxes with security comparable to some of the existing S-boxes constructed via different mathematical structures.

关键词： Substitution box Finite field Mordell elliptic curve Total order Computational complexity

Effects of geometrical and physical factors on light particles dispersion by agitation characteristic curve

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2313-2324页

作者： Meng Li Yangbo Tan Yufeng Liu Jianglong Sun De Xie Zeng Liu School of Naval Architecture and Ocean Engineering Huazhong University of Science and TechnologyWuhan 430074China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE) Shanghai 200240China Hubei Key Laboratory of Naval Architecture and Ocean Engineering Hydrodynamics(HUST) Wuhan 430074China

In this study,the effects of geometrical and physical factors on light particles dispersion in stirred tank were investigated by agitation characteristic *** experiments and CFD simulations with discrete phase model(DPM)and volume of fluid model(VOF)were conducted in this *** factors,which include four geometrical factors(submergence,impeller-to-tank ratio,number of impeller blades and baffling mode)and a physical factor(liquid viscosity)were *** each factor,the power consumption curve and agitation characteristic curve were drawn to compare the power consumption and mixing results in the stirred *** of the agitation characteristic curves were compared with the previous published literatures and *** is found that the agitation characteristic curves reflect the tendency of power consumption and particles distribution well in stirred *** good agreement indicates the applicability of the agitation characteristic curves for the study of light particles distribution in stirred tank.

关键词： Agitation characteristic curve Geometrical and physical factors Light particles Solid–liquid mixing Stirred tank

Integrable curve Motions in n-Dimensional Centro-Affine Geometries

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Chinese Physics Letters 2010年第3期27卷 5-8页

作者：李艳艳 Institute of Mathematics and Information Science Xianyang Normal University Xianyang 712000

Motions of curves in n-dimensional （n ≥ 4） centro-affine geometries are studied. It is shown that the 1＋1-dimensional KdV equations and their hierarchy satisfied by the curvatures of curves under inextensible moti... 详细信息

关键词： Integrable curve Motions

Convergence of Solutions of General Dispersive Equations Along curve

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Chinese Annals of Mathematics,Series B 2019年第3期40卷 363-388页

作者： Yong DING Yaoming NIU School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematics and Complex Systems (BNU) Ministry of Education Faculty of Mathematics Baotou Teachers' College

In this paper, the authors give the local L^2 estimate of the maximal operator S_(φ,γ)~* of the operator family {S_(t,φ,γ)} defined initially by ■which is the solution(when n = 1) of the following dispersive equations(~*) along a curve γ:■where φ : R^+→R satisfies some suitable conditions and φ((-?)^(1/2)) is a pseudo-differential operator with symbol φ(|ξ|). As a consequence of the above result, the authors give the pointwise convergence of the solution(when n = 1) of the equation(~*) along curve γ.Moreover, a global L^2 estimate of the maximal operator S_(φ,γ)~* is also given in this paper.

关键词： L^2 estimate Global maximal operator Dispersive equation curve

Characteristics of soil water retention curve at macro-scale

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Science China(Technological Sciences) 2009年第10期52卷 2990-2996页

作者： TIAN FuQiang MOU LiQin HU HePing State Key Laboratory of Hydro-Science and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China

Scale adaptable hydrological models have attracted more and more attentions in the hydrological modeling research community, and the constitutive relationship at the macro-scale is one of the most important issues, upon which there are not enough research activities yet. Taking the constitutive relationships of soil water movement--soil water retention curve (SWRC) as an example, this study extends the definition of SWRC at the micro-scale to that at the macro-scale, and aided by Monte Carlo method we demonstrate that soil property and the spatial distribution of soil moisture will affect the features of SWRC greatly. Furthermore, we assume that the spatial distribution of soil moisture is the result of self-organization of climate, soil, ground water and soil water movement under the specific boundary conditions, and we also carry out numerical experiments of soil water movement at the vertical direction in order to explore the relationship between SWRC at the macro-scale and the combinations of climate, soil, and groundwater. The results show that SWRCs at the macro-scale and micro-scale presents totally different features, e.g., the essential hysteresis phenomenon which is exaggerated with increasing aridity index and rising groundwater table. Soil property plays an important role in the shape of SWRC which will even lead to a rectangular shape under drier conditions, and power function form of SWRC widely adopted in hydrological model might be revised for most situations at the macro-scale.

关键词： scale issue constitutive relationship soil water retention curve Richards equation

QSAR study on the non-monotonic dose-response curve of PCBs in chicken embryo hepatocyte bioassay

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Science China Chemistry 2009年第5期52卷 662-669页

作者： YunSong Mu AiQian Zhang ChangAn Gao SuFen Peng LianSheng Wang State Key Laboratory of Pollution Control and Resource Reuse School of Environment Nanjing University Nanjing 210093 China

Endocrine disrupting chemicals (EDCs) in the natural environment exhibit a unique non-monotonic dose-response curve and it is impossible to select one simple index to characterize the bilogogical activity of these compounds. Quantitative structure-activity relationship (QSAR) study on non-monotonic dose-response curve has become a real challenge presently. In order to explore the possible mechanism for the non-monotonic dose-response curve of polychlorinated biphenyls congeners (PCBs) in chicken embryo hepatocyte bioassay, AM1 method of ChemOffice was adopted to calculate necessary structure descriptors for PCBs, while the interactions between PCBs and simulated AhR ligand binding domain (LBD) were analyzed by using FlexX in SYBYL7.0. Different binding modes for PCBs have been distinguished not only from aligned conformation but also from free binding energy. Some QSAR models were established separately for both low and high doses ranges, revealing that receptor binding may predominate in the interference of the physiological function of cytochrome P4501A-P4501A in the low doses range. But with the higher doses range, the EROD suppression might be related to acute toxicity owing to molecular polarity or distribution of charges and consequently damage structure and function of chicken embryo hepatocyte.

关键词： polychlorinated biphenyls congeners (PCBs) non-monotonic dose-response curve quantitative structure-activity relationship (QSAR)

Carrying capacity for the electromagnetic suspension low-speed maglev train on the horizontal curve

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Science China(Technological Sciences) 2010年第4期53卷 1082-1087页

作者： CUI Peng,LI Jie & LIU DeSheng Maglev Engineering Center,National University of Defense Technology,Changsha 410073,China Maglev Engineering Center National University of Defense Technology Changsha China

Aiming at the lateral dislocation between the electromagnets and the rails on a horizontal curve,we investigated a single magnetic bogie of the maglev train in this *** magnetic levitation and guidance forces supplied by the suspension modules were deduced by the flux tube *** to the dynamic equilibrium equations of the maglev train on the curved track with cant,several major factors that influence the carrying capacity were analyzed,and the formula of the carrying capacity was *** results provide a theoretical reference for the design of maglev train.

关键词： low-speed maglev train curve flux tube carrying capacity

PH-spline approximation for Bézier curve and rendering offset

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2004年第3期5卷 94-100页

作者：郑志浩汪国昭 Department of Mathematics Zhejiang University

In this paper, a G1, C1, C2 PH-spline is employed as an approximation for a given Bzier curve within error bound and further renders offset which can be regarded as an approximate offset to the Bzier curve. The errors between PH-spline and the Bzier curve, the offset to PH-spline and the offset to the given Bzier curve are also estimated. A new algorithm for constructing offset to the Bzier curve is proposed.

关键词： PH-spline Bézier curve Offset Approximation Error

Ternary surface complexes by the E(%)-pH curve method

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Science China Chemistry 1997年第4期40卷 353-364页

作者：张正斌刘莲生赵宏宾傅有君程凤云赵卫红 Institute of Marine Chemistry Ocean University of QingdaoQingdao 266003China

A new method for the study of ternary surface complexes at liquid-solid interface,the E(%)-pH curve method,was *** types of E(%)-pH curves,namely,phenomenon of left-right shifts of S-shaped curve,V-shaped curve,monodirection shift curve and X-shaped curve,were ***,apart fromtype (Ⅰ) ternary surface complex -S-O-M-L and type (Ⅱ) ternary surface complex -S-L-M,a newtype of ternary surface complex -S-O-L-M was discovered.

关键词： sea water E(%)-pH curve method liquid-solid interface ternary surface complex