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Pseudo S-Asymptotically(ω,c)-Periodic Solutions to Fractional Differential Equations of Sobolev Type
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作者 MAO Hang-ning CHANG Yong-kui 《Chinese Quarterly Journal of Mathematics》 2024年第3期295-306,共12页
In this paper,we firstly recall some basic results on pseudo S-asymptotically(ω,c)-periodic functions and Sobolev type fractional differential equation.We secondly investigate some existence of pseudo S-asymptotical... In this paper,we firstly recall some basic results on pseudo S-asymptotically(ω,c)-periodic functions and Sobolev type fractional differential equation.We secondly investigate some existence of pseudo S-asymptotically(ω,c)-periodic solutions for a semilinear fractional differential equations of Sobolev type.We finally present a simple example. 展开更多
关键词 Pseudo S-asymptotically(ω c)-periodic functions Evolution equations Sobolev type Fractional differential equations Existence and uniqueness
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NEUMANN PROBLEMS OF A CLASS OF ELLIPTIC EQUATIONS WITH DOUBLY CRITICAL SOBOLEV EXPONENTS 被引量:3
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作者 韩丕功 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期633-638,共6页
This paper deals with the Neumann problem for a class of semilinear elliptic equations -△u + u =|u|2*-2u+ μ|u|q-2u in Ω, au/ar= |u|(?)*-2u on aΩ, where 2 = 2N/N-2, s=2(N-1)/N-2, 1 <q<2,N(?)3,μ>γ denotes... This paper deals with the Neumann problem for a class of semilinear elliptic equations -△u + u =|u|2*-2u+ μ|u|q-2u in Ω, au/ar= |u|(?)*-2u on aΩ, where 2 = 2N/N-2, s=2(N-1)/N-2, 1 <q<2,N(?)3,μ>γ denotes the unit outward normal to boundary aΩ. By vaxiational method and dual fountain theorem, the existence of infinitely many solutions with negative energy is proved. 展开更多
关键词 Neumann problem semilinear elliptic equation (PS)·c condition critical Sobolev exponent
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ON THE LIMITABILITY OF SOLUTIONS OF SOME DIFFERENCE EQUATIONS 被引量:1
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作者 L.Rempulska B.Szmanda 《Acta Mathematica Scientia》 SCIE CSCD 1997年第1期64-68,共5页
We investigate limitability by the Cesaio (C, 1) and the Abel (A) methods of solutions of some third and fourth order difference equations. Also some results contained in [2],[3] are improved.
关键词 difference equation (c 1)-limitability (A)-limitability
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Evaluation of C and P Factors in Universal Soil Loss Equation on Trapping Sediment: Case Study of Santubong River 被引量:3
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作者 Kelvin K. K. Kuok Darrien Y. S. Mah P. C. Chiu 《Journal of Water Resource and Protection》 2013年第12期1149-1154,共6页
Universal Soil Loss Equation (USLE) is the most comprehensive technique available to predict the long term average annual rate of erosion on a field slope. USLE was governed by five factors include soil erodibility fa... Universal Soil Loss Equation (USLE) is the most comprehensive technique available to predict the long term average annual rate of erosion on a field slope. USLE was governed by five factors include soil erodibility factor (K), rainfall and runoff erodibility index (R), crop/vegetation and management factor (C), support practice factor (P) and slope length-gradient factor (LS). In the past, K, R and LS factors are extensively studied. But the impacts of factors C and P to outfall Total Suspended Solid (TSS) and % reduction of TSS are not fully studied yet. Therefore, this study employs Buffer Zone Calculator as a tool to determine the sediment removal efficiency for different C and P factors. The selected study areas are Santubong River, Kuching, Sarawak. Results show that the outfall TSS is increasing with the increase of C values. The most effective and efficient land use for reducing TSS among 17 land uses investigated is found to be forest with undergrowth, followed by mixed dipt. forest, forest with no undergrowth, cultivated grass, logging 30, logging 10^6, wet rice, new shifting agriculture, oil palm, rubber, cocoa, coffee, tea and lastly settlement/cleared land. Besides, results also indicate that the % reduction of TSS is increasing with the decrease of P factor. The most effective support practice to reduce the outfall TSS is found to be terracing, followed by contour-strip cropping, contouring and lastly not implementing any soil conservation practice. 展开更多
关键词 Universal Soil Loss equation crop/Vegetation and Management FAcTOR (c) Support Practice FAcTOR (P) OUTFALL TOTAL Suspended SOLID % Reduction of TOTAL Suspended SOLID
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Complete solution of the diophantine equation A^2x^4-By^2=1 and some related problems 被引量:1
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作者 曹珍富 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第2期108-110,共3页
We prove that diophantine equation in title has at most one positive integer solution for any positive integers A>1, B>1. It follows that Lucas problem is very simple to solve and a recent result of Bennett ... We prove that diophantine equation in title has at most one positive integer solution for any positive integers A>1, B>1. It follows that Lucas problem is very simple to solve and a recent result of Bennett is very simple to prove. 展开更多
关键词 quartic diophantine equation cOMPUTER c++
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A General Hermitian Nonnegative-Definite Solution to the Matrix Equation <i>AXB</i>= <i>C</i> 被引量:2
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作者 Phil D. Young Dean M. Young Marsha M. Young 《Advances in Linear Algebra & Matrix Theory》 2017年第1期7-17,共11页
We derive necessary and sufficient conditions for the existence of a Hermitian nonnegative-definite solution to the matrix equation AXB = C. Moreover, we derive a representation of a general Hermitian nonnegative-defi... We derive necessary and sufficient conditions for the existence of a Hermitian nonnegative-definite solution to the matrix equation AXB = C. Moreover, we derive a representation of a general Hermitian nonnegative-definite solution. We then apply our solution to two examples, including a comparison of our solution to a proposed solution by Zhang in [1] using an example problem given from [1]. Our solution demonstrates that the proposed general solution from Zhang in [1] is incorrect. We also give a second example in which we derive the general covariance structure so that two matrix quadratic forms are independent. 展开更多
关键词 Matrix equation AXB = c Generalized Inverse MATRIcES Parallel Summable MATRIcES SYMMETRIZATION Device
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Accuracy of glomerular filtration rate estimation equations in patients with hematopathy
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作者 Han Sun Xiaohua Pei +1 位作者 Jianqing Wu Weihong Zhao 《The Journal of Biomedical Research》 CAS CSCD 2019年第1期46-55,共10页
Renal dysfunction is a common side-effect of chemotherapeutic agents in patients with hematopathy. Although broadly used, glomerular filtration rate(GFR) estimation equations were not fully validated in this specific ... Renal dysfunction is a common side-effect of chemotherapeutic agents in patients with hematopathy. Although broadly used, glomerular filtration rate(GFR) estimation equations were not fully validated in this specific population. Thus, this study was designed to further assess the accuracy of various GFR equations, including the newly 2012 CKD-EPI equations. Referring to ^(99m)Tc-DTPA clearance method, three Scr-based(MDRD, Peking, and CKD-EPI_(Scr)), three Scys C-based(Steven 1, Steven 2, and CKD-EPI_(Scys C)), and three Scr-Scys C combination based(Ma, Steven 3, and CKD-EPI_(Scr-Scys C)) equations were included. Bias, P_(30), and misclassification rate were applied to compare the applicability of the selected equations. A total of 180 Chinese hematological patients were enrolled.Mean bias, absolute mean bias, P_(30), misclassification rate and Bland-Altman plots of the CKD-EPI_(Scr-Scys C) equation were 7.90 mL/minute/1.73 m^2, 17.77 mL/minute/1.73 m^2, 73.3%, 38% and 79.7 mL/minute/1.73 m^2, respectively.CKD-EPI_(Scr-Scys C) predicted the most precise eGFR both in lymphoma and leukemia subgroups. Additionally, CKDEPI_(Scys C) equation in the rGFR■90 mL/minute/1.73 m^2 subgroup and Steven 2 equation in the rGFR<90 mL/minute/1.73 m^2 subgroup provided more accurate estimates in each subgroup. The CKD-EPI_(Scr-Scys C) equation could be recommended to monitor kidney function in hematopathy patients. The accuracy of GFR equations may be closely related with GFR level and kidney function markers, but not the primary cause of hematopathy. 展开更多
关键词 cREATININE cYSTATIN c equation glomerular FILTRATION rate hematopathy
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THE GLOBAL AND LOCAL C^(2)-SOLUTIONS FOR THE WAVE EQUATION □u = G(u_t, Du) IN THREE SPACE DIMENSIONS 被引量:2
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作者 赖绍永 《Acta Mathematica Scientia》 SCIE CSCD 2000年第4期495-503,共9页
Kunio Hidano[4] has shown that the global and local C2-solutions for semilinear wave equations with spherical symmetry in three space dimensions. This paper studies the global and local C2-solutions for the semilinea... Kunio Hidano[4] has shown that the global and local C2-solutions for semilinear wave equations with spherical symmetry in three space dimensions. This paper studies the global and local C2-solutions for the semilinear wave equations without spherical symmetry in three space dimensions. A problem put forward by Hiroyuki Takamura[2] is partially answered. 展开更多
关键词 Semilinear wave equations global and local c^(2)-solutions three space dimensions
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Least-squares finite-element method for shallow-water equations with source terms 被引量:2
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作者 Shin-Jye Liang Tai-Wen Hsu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第5期597-610,共14页
Numerical solution of shallow-water equations (SWE) has been a challenging task because of its nonlinear hyperbolic nature, admitting discontinuous solution, and the need to satisfy the C-property. The presence of s... Numerical solution of shallow-water equations (SWE) has been a challenging task because of its nonlinear hyperbolic nature, admitting discontinuous solution, and the need to satisfy the C-property. The presence of source terms in momentum equations, such as the bottom slope and friction of bed, compounds the difficulties further. In this paper, a least-squares finite-element method for the space discretization and θ-method for the time integration is developed for the 2D non-conservative SWE including the source terms. Advantages of the method include: the source terms can be approximated easily with interpolation functions, no upwind scheme is needed, as well as the resulting system equations is symmetric and positive-definite, therefore, can be solved efficiently with the conjugate gradient method. The method is applied to steady and unsteady flows, subcritical and transcritical flow over a bump, 1D and 2D circular dam-break, wave past a circular cylinder, as well as wave past a hump. Computed results show good C-property, conservation property and compare well with exact solutions and other numerical results for flows with weak and mild gradient changes, but lead to inaccurate predictions for flows with strong gradient changes and discontinuities. 展开更多
关键词 Shallow-water equations Source terms Least-squares finite-element method DAM-BREAK c-property
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Operator Semi-group of Density Evolution Equation for a Repairable Redundant System with Two Same Components
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作者 史定华 徐洪 +1 位作者 熊勇 王远第 《Journal of Shanghai University(English Edition)》 CAS 2002年第4期278-281,共4页
For a repairable redundant system consisting of two same components with exponential lifetime and general repair time distribution, the probability densities of the system in some state at time t were determined b... For a repairable redundant system consisting of two same components with exponential lifetime and general repair time distribution, the probability densities of the system in some state at time t were determined by a group of ordinary and partial differential equations, called density evolution equations. It was proved that the time dependent solution of the density evolution equations uniquely exists and strongly converges to its steady state density solution by a semi group method. In this proof, it is not necessary to suppose that the repair rate function is bounded. The technique of the proof is valuable for many density evolution equations. 展开更多
关键词 stochastic model repairable redundant system density evolution equation c 0 semi group.
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C_0-Semigroup Method of the Density Evolution Equation for M/M/∞ Model
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作者 SHI Ding hua, XIONG Yong, XU Hong College of Sciences, Shanghai University, Shanghai 200436, China 《Journal of Shanghai University(English Edition)》 CAS 2001年第4期265-268,共4页
In this paper, the existence, uniqueness, and asymptotic behavior of the solution of the density evolution equation for M/M/∞ model was studied by the semigroup theory of linear operators.
关键词 M/M/∞ model density evolution equation c 0-semigroup
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On C^(1 ,α) Regularity for Monge- Ampre Equation
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作者 胡云姣 保继光 《Northeastern Mathematical Journal》 CSCD 2000年第1期46-50,共5页
In this paper, we establish global C 1,1/4 estimates for the Dirichlet problem for the Monge Ampère equation, which yield the corresponding existence and regularity results. Our conditions apply to both deg... In this paper, we establish global C 1,1/4 estimates for the Dirichlet problem for the Monge Ampère equation, which yield the corresponding existence and regularity results. Our conditions apply to both degenerate and nondegenerate cases. 展开更多
关键词 Global c 1 1/4 regularity Monge Ampère equation degenerate and nondegenerate cases
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ON THE EXISTENCE OF SOLUTIONS TO D'-VALUED STOCHASTIC DIFFERENTIAL EQUATIONS INVOLVING EVOLUTION DRIFT
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作者 吴奖伦 《Acta Mathematica Scientia》 SCIE CSCD 1995年第S1期91-102,共12页
In this paper, nonstandard analysis is employed to present an existence theory of -valued stochastic differential equations involving evolution drift. And (C0, 1)-evolution systems are also defined and investigated on... In this paper, nonstandard analysis is employed to present an existence theory of -valued stochastic differential equations involving evolution drift. And (C0, 1)-evolution systems are also defined and investigated on dual multi-Hilbertian spaces. 展开更多
关键词 calibration (c0 1)-evolution system Stable family Stochastic differential equations of It type two Loeb spaces Nonstandard analysis
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C1-Conforming Quadrilateral Spectral Element Method for Fourth-Order Equations
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作者 Huiyuan Li Weikun Shan Zhimin Zhang 《Communications on Applied Mathematics and Computation》 2019年第3期403-434,共32页
This paper is devoted to Professor Benyu Guo's open question on the C1-conforming quadrilateral spectral element method for fourth-order equations which has been endeavored for years. Starting with generalized Jac... This paper is devoted to Professor Benyu Guo's open question on the C1-conforming quadrilateral spectral element method for fourth-order equations which has been endeavored for years. Starting with generalized Jacobi polynomials on the reference square, we construct the C1-conforming basis functions using the bilinear mapping from the reference square onto each quadrilateral element which fall into three categories-interior modes, edge modes, and vertex modes. In contrast to the triangular element, compulsively compensatory requirements on the global C1-continuity should be imposed for edge and vertex mode basis functions such that their normal derivatives on each common edge are reduced from rational functions to polynomials, which depend on only parameters of the common edge. It is amazing that the C1-conforming basis functions on each quadrilateral element contain polynomials in primitive variables, the completeness is then guaranteed and further confirmed by the numerical results on the Petrov-Galerkin spectral method for the non-homogeneous boundary value problem of fourth-order equations on an arbitrary quadrilateral. Finally, a C1-conforming quadrilateral spectral element method is proposed for the biharmonic eigenvalue problem, and numerical experiments demonstrate the effectiveness and efficiency of our spectral element method. 展开更多
关键词 QUADRILATERAL spectral element method FOURTH-ORDER equations Mapped POLYNOMIALS c1-conforming basis Polynomial INcLUSION cOMPLETENESS
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C-Bézier基函数在稳态线弹性方程求解中的应用
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作者 孙兰银 庞琨琨 《信阳师范学院学报(自然科学版)》 CAS 2024年第2期197-202,共6页
用有限元方法求解稳态线弹性方程,以C-Bézier基函数作为参考元上的形函数,通过选取适当的形状参数,在步长不变的情况下,所得到的数值解精度比传统的Lagrange基函数在L∞、L 2范数下高3个数量级以上,在H 1半范数下高2~6个数量级,充... 用有限元方法求解稳态线弹性方程,以C-Bézier基函数作为参考元上的形函数,通过选取适当的形状参数,在步长不变的情况下,所得到的数值解精度比传统的Lagrange基函数在L∞、L 2范数下高3个数量级以上,在H 1半范数下高2~6个数量级,充分说明了C-Bézier基函数在求解稳态线弹性方程时具有更好的逼近效果。 展开更多
关键词 稳态线弹性方程 有限元方法 c-Bézier基函数
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Tensor-Centric Warfare I: Tensor Lanchester Equations
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作者 Vladimir Ivancevic Peyam Pourbeik Darryn Reid 《Intelligent Control and Automation》 2018年第2期11-29,共19页
We propose the basis for a rigorous approach to modeling combat, specifically under conditions of complexity and uncertainty. The proposed basis is a tensorial generalization of earlier Lanchester-type equations, insp... We propose the basis for a rigorous approach to modeling combat, specifically under conditions of complexity and uncertainty. The proposed basis is a tensorial generalization of earlier Lanchester-type equations, inspired by the contemporary debate in defence and military circles around how to best utilize information and communications systems in military operations, including the distributed C4ISR system (Command, Control, Communications, Computing, Intelligence, Surveillance and Reconnaissance). Despite attracting considerable interest and spawning several efforts to develop sound theoretical frameworks for informing force design decision-making, the development of good frameworks for analytically modeling combat remains anything but decided. Using a simple combat scenario, we first develop a tensor generalization of the Lanchester square law, and then extend it to also include the Lanchester linear law, which represents the effect of suppressive fire. We also add on-off control inputs, and discuss the results of a simple simulation of the final model using our small scenario. 展开更多
关键词 TENSOR Modeling of cOMPLEX Warfighting Lanchester-Type cOMBAT equationS c4ISR MILITARY System
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HLDER CONTINUOUS SOLUTIONS FOR SECOND ORDER INTEGRO-DIFFERENTIAL EQUATIONS IN BANACH SPACES
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作者 步尚全 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期765-777,共13页
We study Hlder continuous solutions for the second order integro-differential equations with infinite delay (P1): u′′(t)+cu′(t)+∫t-∞β(t-s)u′(s)ds+∫t-∞γ(t-s)u(s)ds = Au(t)-∫t-∞δ(t-s)A... We study Hlder continuous solutions for the second order integro-differential equations with infinite delay (P1): u′′(t)+cu′(t)+∫t-∞β(t-s)u′(s)ds+∫t-∞γ(t-s)u(s)ds = Au(t)-∫t-∞δ(t-s)Au(s)ds + f(t)on the line R, where 0 〈 α 〈 1, A is a closed operator in a complex Banach space X, c ∈ C is a constant, f ∈ Cα(R,X) and β,γ,δ∈L1(R+).Under suitable assumptions on the kernels β, γ and δ, we completely characterize the Cα- well-posedness of (P_1) by using operator-valued Cα-Fourier multipliers. 展开更多
关键词 Fourier multiplier c~α-well-posedness integro-differential equations
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^(60)CO-r射线辐射辣椒(甜椒)种子诱变效应研究 被引量:5
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作者 徐宝连 张爱莲 +1 位作者 刘艳芝 徐祥文 《安徽农学通报》 2007年第19期56-56,121,共2页
采用60CO-r射线1-5万伦琴对辣椒(甜椒)种子进行辐射处理,结果表明:对辣椒(甜椒)品种之间发芽率和出苗率影响很大,随着辐射剂量增加,辣椒(甜椒)的发芽率和出苗率逐渐降低。辣椒在1万伦琴低剂量处理,辣椒植株茎粗、茎高、地上部鲜重与对... 采用60CO-r射线1-5万伦琴对辣椒(甜椒)种子进行辐射处理,结果表明:对辣椒(甜椒)品种之间发芽率和出苗率影响很大,随着辐射剂量增加,辣椒(甜椒)的发芽率和出苗率逐渐降低。辣椒在1万伦琴低剂量处理,辣椒植株茎粗、茎高、地上部鲜重与对照差别不大,个别植株有所增加,但变异频率很低。当剂量增加,出苗率降低,变异频率增加;在4万伦琴的剂量以上,处于半致死剂量;最适宜的辐射剂量2万伦琴。甜椒在3万伦琴的剂量以上,处于半致死剂量;最适宜的辐射剂量1.5-2万伦琴。 展开更多
关键词 60c0-r射线 辣椒(甜椒) 诱变效应
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EG7564C-RS点阵液晶的开发应用
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作者 谭小丹 邓亲恺 《电子技术应用》 北大核心 2003年第2期69-71,共3页
介绍了EPSONEG7564C-RS点阵液晶和Motorola16位单片机MC68HC16Z1的硬件连接电路以及在该液晶上的画点程序和图片显示程序。该程序可以在液晶任意位置上显示任意字符、图片,其设计方案可应用于各种选用点阵液晶显示的微型仪器的界面设计中。
关键词 Mc68Hc16Z1单片机 EG7564-rS点阵液晶 c语言 显示器
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复变函数中C.-R方程的教学过程分析
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作者 李顺利 宋春丽 +1 位作者 管毅 姚廷富 《贵阳学院学报(自然科学版)》 2018年第1期1-2,共2页
在复变函数中,C.-R.V方程,即柯西-黎曼方程是讨论函数解析性的核心内容,也是研究柯西积分定理的基础,本文针对实际教学中学生的学习情况对C.-R.方程的教学过程做了进一步分析与优化。
关键词 复变函数 c.-r.方程 教学过程
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