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三次方程解析法冒口计算 被引量:12
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作者 高尚书 于志亚 《铸造》 EI CAS CSCD 北大核心 2000年第9期533-537,共5页
在铸钢件冒口设计中 ,模数法是一个广泛应用的计算方法 ,三次方程解析法是模数法中较为严密的计算方法。笔者通过数学推导 ,给出三次方程解析法中冒口当量直径的代数解 ,该法方便、准确、实用 ,同时 ,准确的数学模型更有利于铸造工艺CA... 在铸钢件冒口设计中 ,模数法是一个广泛应用的计算方法 ,三次方程解析法是模数法中较为严密的计算方法。笔者通过数学推导 ,给出三次方程解析法中冒口当量直径的代数解 ,该法方便、准确、实用 ,同时 ,准确的数学模型更有利于铸造工艺CAD的使用与推广。文中还给出铸钢件冒口计算的形状系数计算方法。 展开更多
关键词 模数法 三次方程解析法 冒口计算 铸钢件
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An Extension of Mapping Deformation Method and New Exact Solution for Three Coupled Nonlinear Partial Differential Equations 被引量:11
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作者 LIHua-Mei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4期395-400,共6页
In this paper, we extend the mapping deformation method proposed by Lou. It is used to find new exacttravelling wave solutions of nonlinear partial differential equation or coupled nonlinear partial differential equat... In this paper, we extend the mapping deformation method proposed by Lou. It is used to find new exacttravelling wave solutions of nonlinear partial differential equation or coupled nonlinear partial differential equations(PDEs). Based on the idea of the homogeneous balance method, we construct the general mapping relation betweenthe solutions of the PDEs and those of the cubic nonlinear Klein-Gordon (NKG) equation. By using this relation andthe abundant solutions of the cubic NKG equation, many explicit and exact travelling wave solutions of three systemsof coupled PDEs, which contain solitary wave solutions, trigonometric function solutions, Jacobian elliptic functionsolutions, and rational solutions, are obtained. 展开更多
关键词 coupled nonlinear partial differential equations cubic nonlinear Klein-Gordon equation exact solution
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2~k元域上的三次方程根的状况 被引量:9
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作者 孙宗明 《内蒙古师范大学学报(自然科学汉文版)》 CAS 1993年第2期21-26,共6页
F是一个2~k元域。本文证明:研究域F上的三次方程可以转化为研究方程x^3+ax+b=0(a≠0)。然后得到方程x^3+ax+b=0(a≠0)在域F中有一零根与二重根,或三个互异的根,或一个根,或没有根。从而,完整地解决了域F上三次方程的问题。
关键词 三次方程 2^k元域
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三次对称多项式x^3+y^3+z^3-3xyz的因式分解及其应用(Ⅰ) 被引量:7
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作者 刘合国 徐行忠 雒晓良 《湖北大学学报(自然科学版)》 CAS 2019年第2期182-191,197,共11页
从三次对称多项式x^3+y^3+z^3-3xyz的因式分解出发,给出这个分解在恒等式证明、代数式简化、3次方程求根等方面的直接应用.
关键词 对称多项式 因式分解 3次方程
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向量混合积的应用探讨
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作者 郑剑平 余新宏 +3 位作者 朱文君 梁林 王礼霞 李莉 《安顺学院学报》 2024年第1期115-118,共4页
向量的数量积、向量积和混合积是高等数学中向量代数与空间解析几何的重要内容。通过计算四面体体积、平面方程、直线方程和判断两直线异面四个方面探讨向量混合积的应用,为一题多解拓宽解题思路,优化解题方法,有利于提高学生学习兴趣,... 向量的数量积、向量积和混合积是高等数学中向量代数与空间解析几何的重要内容。通过计算四面体体积、平面方程、直线方程和判断两直线异面四个方面探讨向量混合积的应用,为一题多解拓宽解题思路,优化解题方法,有利于提高学生学习兴趣,提升高等数学教学效果和教学质量。 展开更多
关键词 向量混合积 四面体体积 平面方程 直线方程 两直线异面
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Stability Problem for Jensen-type Functional Equations of Cubic Mappings 被引量:5
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作者 Kil-WoungJUN Hark-MahnKIM 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第6期1781-1788,共8页
In this paper, we establish the general solution and the generalized Hyers-Ulam-Rassias stability problem for a cubic Jensen-type functional equation,4f((3x+y)/4)+4f((x+3y)/4)=6f((x+y)/2)+f(x)+f(y... In this paper, we establish the general solution and the generalized Hyers-Ulam-Rassias stability problem for a cubic Jensen-type functional equation,4f((3x+y)/4)+4f((x+3y)/4)=6f((x+y)/2)+f(x)+f(y),9f((2x+y/3)+9f((x+2y)/3)=16f((x+y)/2+f(x)+f(y)in the spirit of D. H. Hyers, S. M. Ulam, Th. M. Rassias and P. Gaevruta. 展开更多
关键词 Jensen equation Hyers-Ulam-Rassias stability cubic mapping
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Accounting for Quadratic and Cubic Invariants in Continuum Mechanics–An Overview
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作者 Artur V.Dmitrenko Vladislav M.Ovsyannikov 《Fluid Dynamics & Materials Processing》 EI 2024年第9期1925-1939,共15页
The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related fields.These equations contain derivatives of the first ... The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related fields.These equations contain derivatives of the first order with respect to time.The derivation of the equations of continuum mechanics uses the limit transitions of the tendency of the volume increment and the time increment to zero.Derivatives are used to derive the wave equation.The differential wave equation is second order in time.Therefore,increments of volume and increments of time in continuum mechanics should be considered as small but finite quantities for problems of wave formation.This is important for calculating the generation of sound waves and water hammer waves.Therefore,the Euler continuity equation with finite time increments is of interest.The finiteness of the time increment makes it possible to take into account the quadratic and cubic invariants of the strain rate tensor.This is a new branch in hydrodynamics.Quadratic and cubic invariants will be used in differential wave equations of the second and third order in time. 展开更多
关键词 Quadratic invariant cubic invariant continuity equation generation of periodic waves N.E.Zhukovsky’s hydraulic shock TURBULENCE
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Solitary Waves for Cubic-Quintic Nonlinear Schroedinger Equation with Variable Coefficients 被引量:6
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作者 ZHANG Jin-Liang WANG Ming-Liang LI Xiang-Zheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2期343-346,共4页
The cubic-quintic nonlinear Schroedinger equation (CQNLS) plays important parts in the optical fiber and the nuclear hydrodynamics. By using the homogeneous balance principle, the bell type, kink type, algebraic sol... The cubic-quintic nonlinear Schroedinger equation (CQNLS) plays important parts in the optical fiber and the nuclear hydrodynamics. By using the homogeneous balance principle, the bell type, kink type, algebraic solitary waves, and trigonometric traveling waves for the cubic-quintic nonlinear Schroedinger equation with variable coefficients (vCQNLS) are derived with the aid of a set of subsidiary high-order ordinary differential equations (sub-equations for short). The method used in this paper might help one to derive the exact solutions for the other high-order nonlinear evolution equations, and shows the new application of the homogeneous balance principle. 展开更多
关键词 cubic-quintic nonlinear Schroedinger equation with variable coefficients homogeneous balance principle solitary wave
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立方型状态方程研究进展 被引量:4
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作者 马海龙 项曙光 《河北化工》 2007年第11期16-19,共4页
概括了立方型状态方程的进展,介绍了立方型状态方程的特点。分析了各类立方型状态方程存在的问题,提出了解决的方法。对立方型状态方程的应用进行了阐述,指出了其仍然具有很大的研究价值。
关键词 立方型 状态方程 温度函数
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沥青混凝土双轴压缩强度试验研究
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作者 锁利军 栗培龙 王秉纲 《武汉理工大学学报(交通科学与工程版)》 2023年第2期307-311,共5页
文中对五个不同油石比成型的立方体试件进行了双轴压缩强度试验研究.结果表明:加载速率2、5.08 mm/min时,15、20℃的双轴强度明显高于20、25℃的值.加载速率8.16 mm/min,当油石比从4.5%到5.5%时,25℃的双轴强度值高于20℃的值.应力-应... 文中对五个不同油石比成型的立方体试件进行了双轴压缩强度试验研究.结果表明:加载速率2、5.08 mm/min时,15、20℃的双轴强度明显高于20、25℃的值.加载速率8.16 mm/min,当油石比从4.5%到5.5%时,25℃的双轴强度值高于20℃的值.应力-应变曲线具有前期小范围线性增长,中期非线性快速增长,后期增长趋缓的特点.得到了双轴压缩强度的回归模型. 展开更多
关键词 道路工程 沥青混凝土 第二主应力 立方体试件 双轴压缩试验 强度 回归模型
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New Generalized Transformation Method and Its Application in Higher-Dimensional Soliton Equation 被引量:2
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作者 BAI Cheng-Lin GUO Zong-Lin ZHAO Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期447-451,共5页
A new generalized transformation method is differential equation. As an application of the method, we presented to find more exact solutions of nonlinear partial choose the (3+1)-dimensional breaking soliton equati... A new generalized transformation method is differential equation. As an application of the method, we presented to find more exact solutions of nonlinear partial choose the (3+1)-dimensional breaking soliton equation to illustrate the method. As a result many types of explicit and exact traveling wave solutions, which contain solitary wave solutions, trigonometric function solutions, Jacobian elliptic function solutions, and rational solutions, are obtained. The new method can be extended to other nonlinear partial differential equations in mathematical physics. 展开更多
关键词 new generalized transformation method exact solution (3+1)-dimensional breaking soliton equation KdV equation mKdV equation cubic nonlinear Klein-Gordon equation
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P^K(P>3)元域上的三次方程根的状况 被引量:3
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作者 孙宗明 《长沙大学学报》 2000年第4期13-17,21,共6页
F是一个PK(P >3)元域 .本文证明 :研究F上的三次方程可以转化为研究方程x3+ax +b =0 (a≠ 0 ,b≠ 0 ) .然后得到x3+ax +b =0 (a≠ 0 ,b≠ 0 )在域F中有且仅有一根 ,或一个单根与一个二重根 ,或三个互异的根 ,或没有根 .最后 。
关键词 P^K元域 三次方程 单根 二重根 有限域 互异根 无根 分裂域
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3^k元域上的三次方程根的简况 被引量:3
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作者 孙宗明 牟兴祥 李振国 《广西师院学报(自然科学版)》 1995年第2期32-34,共3页
F是一个3k元域,x3+ax2+bx+c=0是F上的三次方程。该文证明方程x3+ax2+bx+c=0在F中有一根,或一根与二重根,或三个互异的根,或没有根。
关键词 三次方程 3^k元域
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三次对称多项式x^3+y^3+z^3-3xyz的因式分解及其应用(Ⅱ) 被引量:3
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作者 刘合国 高睿 +1 位作者 徐行忠 雒晓良 《湖北大学学报(自然科学版)》 CAS 2019年第6期592-602,共11页
本研究是文献[1]的继续,给出三次对称多项式x^3+y^3+z^3-3xyz的因式分解的进一步应用.
关键词 对称多项式 因式分解 3次方程
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p^k元域上的三次方程根的状况 被引量:3
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作者 孙宗明 《内蒙古师范大学学报(自然科学汉文版)》 CAS 2001年第3期216-219,共4页
完整地给出了F(设F是一个pk 元域 )上的三次方程根的状况 :在F中有且仅有一个根 ,或一个单根与一个二重根 ,或三个互异的根 ,或没有根 .
关键词 P^K元域 三次方程 单根 二重根 三个互异根 乘法群 单位元 零元
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Finite Symmetry Transformation Groups and Some Exact Solutions to(2+1)-Dimensional Cubic Nonlinear Schrdinger Equantion 被引量:3
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作者 LI Biao LI Yu-Qi CHEN Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期773-776,共4页
Making use of the direct method proposed by Lou et al. and symbolic computation, finite symmetry transformation groups for a (2+ l)-dimensional cubic nonlinear Schrodinger (NLS) equation and its corresponding cyl... Making use of the direct method proposed by Lou et al. and symbolic computation, finite symmetry transformation groups for a (2+ l)-dimensional cubic nonlinear Schrodinger (NLS) equation and its corresponding cylindrical NLS equations are presented. Nine related linear independent infinitesimal generators can be obtained from the finite symmetry transformation groups by restricting the arbitrary constants in infinitesimal forms. Some exact solutions are derived from a simple travelling wave solution. 展开更多
关键词 symmetry groups cubic NLS equation exact solution
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Spatiotemporal Similaritons in (3+l)-Dimensional Inhomogeneous Nonlinear Medium with Cubic-Quintic Nonlinearity 被引量:3
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作者 陈翼翔 陆璇辉 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第5期871-877,共7页
We obtain exact spatiotemporal similaritons to a (3+ l)-dimensional inhomogeneous nonlinear Schrodinger equation, which describes the propagation of optical pulses in a cubic-quintic nonlinearity medium with distri... We obtain exact spatiotemporal similaritons to a (3+ l)-dimensional inhomogeneous nonlinear Schrodinger equation, which describes the propagation of optical pulses in a cubic-quintic nonlinearity medium with distributed dispersion and gain. A one-to-one correspondence between such self-similar waves and solutions of the elliptic equation is found when a certain compatibility condition is satisfied. Based on exact solutions, we discuss evolutional behaviors of self-similar cnoidal waves and chirped similaritons in two kind of typicai soliton control systems. Moreover, the comparison between chirped similaritons and chirp-free solitons is given. 展开更多
关键词 spatiotemporal similaritons (3+l)-dimensional cubic-quintic nonlinear SchrSdinger equation dynamical behaviors
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A New General Equation of State 被引量:1
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作者 云志 秦金平 +1 位作者 史美仁 时钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1999年第2期161-165,共5页
A new general equation of state is presented, which can be used to express not only common cubic equations of state, but also quartic equations of state and so on. Main advantage of the new equation over the previous ... A new general equation of state is presented, which can be used to express not only common cubic equations of state, but also quartic equations of state and so on. Main advantage of the new equation over the previous general equations is that it is in simple form, and is easy to manipulate mathematically. 展开更多
关键词 equation of state general equation cubic equation quartic equation
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Stability Analysis of Solitary Wave Solutions for Coupled and(2+1)-Dimensional Cubic Klein-Gordon Equations and Their Applications 被引量:2
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作者 Aly R.Seadawy Dian-Chen Lu Muhammad Arshd 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第6期676-686,共11页
The searching exact solutions in the solitary wave form of non-linear partial differential equations (PDEs) play a significant role to understand the internal mechanism of complex physical phenomena. In this paper w... The searching exact solutions in the solitary wave form of non-linear partial differential equations (PDEs) play a significant role to understand the internal mechanism of complex physical phenomena. In this paper we employ the proposed modified extended mapping method for constructing the exact solitary wave and soliton solutions of coupled Klein-Gordon equations and the (2-1-1)-dimensional cubic Klein-Gordon (K-G) equation. The Klein-Gordon equations are relativistic version of Schr6dinger equations, which describe the relation of relativistic energy-momentum in the form of quantized version. We productively achieve exact solutions involving parameters such as dark and bright solitary waves, Kink solitary wave, anti-Kink solitary wave, periodic solitary waves, and hyperbolic functions in which several solutions are novel. We plot the three-dimensional surface of some obtained solutions in this study. It is recognized that the modified mapping technique presents a more prestigious mathematical tool for acquiring analytical solutions of PDEs arise in mathematical physics. 展开更多
关键词 modified extended mapping method coupled Klein-Gordon equation cubic Klein-Gordon equation SOLITONS solitary wave solutions periodic solutions
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n=3和n=4时的Routh-Hurwitz定理的初等证明 被引量:2
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作者 江治杰 《内江师范学院学报》 2020年第8期36-41,共6页
Routh-Hurwitz定理是判断系统稳定性的一个重要准则.原始证明长而复杂,没有被引入教材中.为此,利用分类讨论的方法给出了该定理在n=3和n=4时的初等证明.
关键词 Routh-Hurwitz定理 初等证明 三次方程 四次方程
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