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The Existence of Meromorphic Solutions to Non-Linear Delay Differential Equations
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作者 Mingyue Wu 《Open Journal of Applied Sciences》 2023年第12期2329-2342,共14页
In this paper, we study the existence of the transcendental meromorphic solution of the delay differential equations , where a(z) is a rational function, and are polynomials in w(z) with rational c... In this paper, we study the existence of the transcendental meromorphic solution of the delay differential equations , where a(z) is a rational function, and are polynomials in w(z) with rational coefficients, k is a positive integer. Under the assumption when above equations own transcendental meromorphic solutions with minimal hyper-type, we derive the concrete conditions on the degree of the right side of them. Specially, when w(z)=0 is a root of , its multiplicity is at most k. Some examples are given here to illustrate that our results are accurate. 展开更多
关键词 non-linear Delay Differential Equations Painlevé Type Equations Nevanlinna Theory Meromorphic function Solutions Minimal Hypertype
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NON-LINEAR DYNAMIC MODEL RETRIEVAL OF SUBTROPICAL HIGH BASED ON EMPIRICAL ORTHOGONAL FUNCTION AND GENETIC ALGORITHM
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作者 张韧 洪梅 +4 位作者 孙照渤 牛生杰 朱伟军 闵锦忠 万齐林 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第12期1645-1653,共9页
Aiming at the difficulty of accurately constructing the dynamic model of subtropical high, based on the potential height field time series over 500 hPa layer of T106 numerical forecast products, by using EOF(empirica... Aiming at the difficulty of accurately constructing the dynamic model of subtropical high, based on the potential height field time series over 500 hPa layer of T106 numerical forecast products, by using EOF(empirical orthogonal function) temporal-spatial separation technique, the disassembled EOF time coefficients series were regarded as dynamical model variables, and dynamic system retrieval idea as well as genetic algorithm were introduced to make dynamical model parameters optimization search, then, a reasonable non-linear dynamic model of EOF time-coefficients was established. By dynamic model integral and EOF temporal-spatial components assembly, a mid-/long-term forecast of subtropical high was carried out. The experimental results show that the forecast results of dynamic model are superior to that of general numerical model forecast results. A new modeling idea and forecast technique is presented for diagnosing and forecasting such complicated weathers as subtropical high. 展开更多
关键词 genetic algorithm empirical orthogonal function non-linear model retrieval subtropical high
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Method of Designing Generators of Pseudorandom Sequences for Information Protection Based on Shift Register with Non-Linear Feedback Function
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作者 Saleh Al-Omar 《Journal of Information Security》 2014年第4期218-227,共10页
This paper proposes an efficient, high-tech method of construction of pseudorandom binary sequences generators with a repetition period 2n?for n-bit shift register with a nonlinear feedback function. The developed met... This paper proposes an efficient, high-tech method of construction of pseudorandom binary sequences generators with a repetition period 2n?for n-bit shift register with a nonlinear feedback function. The developed method is illustrated by constructing a nonlinear function feedback shift register. It is proved that the offered method requires the realization of a memory size proportional to n2?that allows making successful use of suitable generators for practical use on the shift register of the longer word. 展开更多
关键词 PSEUDORANDOM SEQUENCES non-linear FEEDBACK function Information Protection
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Delay-dependent Non-fragile H_∞ Filtering for Uncertain Fuzzy Systems Based on Switching Fuzzy Model and Piecewise Lyapunov Function 被引量:1
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作者 Zhi-Le Xia Jun-Min Li Jiang-Rong Li 《International Journal of Automation and computing》 EI 2010年第4期428-437,共10页
This paper is concerned with the non-fragile H∞ filter design problem for uncertain discrete-time Takagi-Sugeno (T-S) fuzzy systems with time delay. To begin with, the T-S fuzzy system is transformed to an equivale... This paper is concerned with the non-fragile H∞ filter design problem for uncertain discrete-time Takagi-Sugeno (T-S) fuzzy systems with time delay. To begin with, the T-S fuzzy system is transformed to an equivalent switching fuzzy system. Then, based on the piecewise Lyapunov function and matrix decoupling technique, a new delay-dependent non-fragile H∞ filtering method is proposed for the switching fuzzy system. The proposed condition is less conservative than the previous results. Since only a set of LMIs is involved, the filter parameters can be solved directly. Finally, a design example is provided to illustrate the validity of the proposed method. 展开更多
关键词 non-fragile H∞ filter DELAY-DEPENDENT piecewise Lyapunov function linear matrix inequalities (LMIs)
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Solution of Dirac Equation with the Time-Dependent Linear Potential in Non-Commutative Phase Space
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作者 Xueling Jiang Chaoyun Long Shuijie Qin 《Journal of Modern Physics》 2013年第7期940-944,共5页
In this paper, the time-dependent invariant of the Dirac equation with time-dependent linear potential has been constructed in non-commutative phase space. The corresponding analytical solution of the Dirac equation i... In this paper, the time-dependent invariant of the Dirac equation with time-dependent linear potential has been constructed in non-commutative phase space. The corresponding analytical solution of the Dirac equation is presented by Lewis-Riesenfield invariant method. 展开更多
关键词 non-COMMUTATIVE DIRAC Equation TIME-DEPENDENT linear POTENTIALS Exact Wave function
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Molecular Structure, Vibrational Assignments and Non-Linear Optical Properties of 4,4’ Dimethylaminocyanobiphenyl (DMACB) by DFT and <i>ab Initio</i>HF Calculations
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作者 Charef Tabti Nadia Benhalima 《Advances in Materials Physics and Chemistry》 2015年第7期221-228,共8页
In the present study, structural properties of 4,4’ dimethylaminocyanobiphenyl (DMACB) have been studied extensively by using ab initio Hartree Fock (HF) and density functional theory (DFT) employing B3LYP/B3PW91 exc... In the present study, structural properties of 4,4’ dimethylaminocyanobiphenyl (DMACB) have been studied extensively by using ab initio Hartree Fock (HF) and density functional theory (DFT) employing B3LYP/B3PW91 exchange correlation levels of theory. The vibrational frequencies of DMACB in the ground state have been calculated by using Hartree Fock level and density functional method (B3LYP/B3PW91) with 6-31G(d, p), basis set. Nonlinear optical (NLO) behavior of the examined molecule is investigated by the determination of the electric dipole moment μ, the polarizability α, and the hyperpolarizability β by using the B3LYP/B3PW91 methods. 展开更多
关键词 Ab INITIO 4 4’ Dimethylaminocyanobiphenyl (DMACB) Dipole Moment POLARIZABILITY HYPERPOLARIZABILITY non-linear Optics (NLO) Vibrational Spectra Density functional Calculations
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A New Fourth Order Difference Approximation for the Solution of Three-dimensional Non-linear Biharmonic Equations Using Coupled Approach
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作者 Ranjan Kumar Mohanty Mahinder Kumar Jain Biranchi Narayan Mishra 《American Journal of Computational Mathematics》 2011年第4期318-327,共10页
This paper deals with a new higher order compact difference scheme, which is, O(h4) using coupled approach on the 19-point 3D stencil for the solution of three dimensional nonlinear biharmonic equations. At each inter... This paper deals with a new higher order compact difference scheme, which is, O(h4) using coupled approach on the 19-point 3D stencil for the solution of three dimensional nonlinear biharmonic equations. At each internal grid point, the solution u(x,y,z) and its Laplacian Δ4u are obtained. The resulting stencil algo-rithm is presented and hence this new algorithm can be easily incorporated to solve many problems. The present discretization allows us to use the Dirichlet boundary conditions only and there is no need to discretize the derivative boundary conditions near the boundary. We also show that special treatment is required to handle the boundary conditions. Convergence analysis for a model problem is briefly discussed. The method is tested on three problems and compares very favourably with the corresponding second order approximation which we also discuss using coupled approach. 展开更多
关键词 THREE-DIMENSIONAL non-linear BIHARMONIC Equation Finite Differences Fourth Order Accuracy Compact Discretization Block-Block-Tridiagonal Tangential Derivatives Laplacian Stream function REYNOLDS Number
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一种NLF-对数小波阈值的脉冲干扰降噪方法 被引量:1
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作者 江莉 向世召 +2 位作者 焦予栋 尚文擎 王燕妮 《小型微型计算机系统》 CSCD 北大核心 2023年第12期2844-2850,共7页
在脉冲噪声背景下,传统信号降噪方法性能退化,无法去除强脉冲噪声,而且会出现计算复杂度增加的问题.本文提出一种基于非线性滤波(Nonlinear Filtering, NLF)和小波阈值去噪的联合算法,该方法利用非线性滤波算法抑制强脉冲噪声点干扰,通... 在脉冲噪声背景下,传统信号降噪方法性能退化,无法去除强脉冲噪声,而且会出现计算复杂度增加的问题.本文提出一种基于非线性滤波(Nonlinear Filtering, NLF)和小波阈值去噪的联合算法,该方法利用非线性滤波算法抑制强脉冲噪声点干扰,通过改进的对数小波阈值函数去噪方法进行全局处理,快速而且高质量的完成对信号降噪.实验结果表明,本文所提算法对脉冲噪声背景下的多种信号类型都具有可行性,能够获得更高的峰值信噪比,具有很好的降噪效果. 展开更多
关键词 脉冲噪声 非线性滤波 小波阈值去噪 硬软阈值函数 峰值信噪比
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FAREY SEQUENCE OF NONLINEAR DIFFERENTIAL DYNAMIC SYSTEM IN TWO DIMENSIONS 被引量:1
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作者 H. Q. Jin and S. N. Xu Shenyang Institute of Technology , Shenyang 110015 , China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第5期1234-1236,共3页
In this paper , through the discrim ination of Farey sequence in the forced Brusselator withweak coupling , it is proved that there is a topological translation fro m a nonlinear differen tial system ( limit cycle)... In this paper , through the discrim ination of Farey sequence in the forced Brusselator withweak coupling , it is proved that there is a topological translation fro m a nonlinear differen tial system ( limit cycle) to the circle m ap . 展开更多
关键词 non - linearity Farey sequence phase lock CHAOS
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Thermal buckling analysis of ceramic-metal functionally graded plates 被引量:3
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作者 Ashraf M. Zenkour Daoud S. Mashat 《Natural Science》 2010年第9期968-978,共11页
Thermal buckling response of functionally graded plates is presented in this paper using sinusoidal shear deformation plate theory (SPT). The material properties of the plate are assumed to vary according to a power l... Thermal buckling response of functionally graded plates is presented in this paper using sinusoidal shear deformation plate theory (SPT). The material properties of the plate are assumed to vary according to a power law form in the thickness direction. Equilibrium and stability equations are derived based on the SPT. The non-linear governing equations are solved for plates subjected to simply supported boundary conditions. The buckling analysis of a functionally graded plate under various types of thermal loads is carried out. The influences of many plate parameters on buckling temperature difference will be investigated. Numerical results are presented for the SPT, demonstrating its importance and accuracy in comparison to other theories. 展开更多
关键词 Thermal BUCKLING non-linear STRAINS functionally GRADED MATERIAL Sinusoidal PLATE
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NON-INTERIOR SMOOTHING ALGORITHM FOR FRICTIONAL CONTACT PROBLEMS 被引量:1
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作者 张洪武 何素艳 李兴斯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第1期47-58,共12页
A new algorithm for solving the three-dimensional elastic contact problem with friction is presented. The algorithm is a non-interior smoothing algorithm based on an NCP-function. The parametric variational principle ... A new algorithm for solving the three-dimensional elastic contact problem with friction is presented. The algorithm is a non-interior smoothing algorithm based on an NCP-function. The parametric variational principle and parametric quadratic programming method were applied to the analysis of three-dimensional frictional contact problem. The solution of the contact problem was finally reduced to a linear complementarity problem, which was reformulated as a system of nonsmooth equations via an NCP-function. A smoothing approximation to the nonsmooth equations was given by the aggregate function. A Newton method was used to solve the resulting smoothing nonlinear equations. The algorithm presented is easy to understand and implement. The reliability and efficiency of this algorithm are demonstrated both by the numerical experiments of LCP in mathematical way and the examples of contact problems in mechanics. 展开更多
关键词 three-dimensional frictional contact problem parametic quadratic programming method linear complementarity problem NCP-function aggregate function non-interior smoothing algorithm
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流密码非线性布尔函数可重构运算单元设计方法RA-NLBF
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作者 张宗仁 戴紫彬 +1 位作者 刘燕江 张晓磊 《计算机应用》 CSCD 北大核心 2023年第11期3527-3533,共7页
分组密码中的S盒(多输出)以及流密码中的反馈函数都需要特殊的布尔函数来保证密码算法的安全性。为解决现有流密码算法中非线性布尔函数(NLBF)可重构硬件运算单元资源占用过大、时钟频率低等问题,提出一种高效的基于与非锥(AIC)的NLBF... 分组密码中的S盒(多输出)以及流密码中的反馈函数都需要特殊的布尔函数来保证密码算法的安全性。为解决现有流密码算法中非线性布尔函数(NLBF)可重构硬件运算单元资源占用过大、时钟频率低等问题,提出一种高效的基于与非锥(AIC)的NLBF可重构运算单元设计方法(RA-NLBF)。以密码学理论为基础,在着重分析多种流密码算法的NLBF特性,提取了涵盖与项次数、与项个数、输入端口数等NLBF函数特征的基础上,提出基于“混合极性Reed-Muller(MPRM)”和“传统布尔逻辑(TB)”双逻辑混合形式的NLBF化简方法,NLBF的与项数量减少29%,形成了适用于AIC的NLBF表达式;根据化简后的表达中与项个数、与项次数分布等特征,设计了可重构AIC单元和互联网络,形成可满足现有公开流密码算法中的NLBF运算的可重构单元。基于CMOS 180 nm工艺对提出的RA-NLBF进行逻辑综合验证,结果显示该方法的面积为12949.67μm^(2),时钟频率达到505 MHz,与现有相同功能的单元可重构序列密码逻辑单元(RSCLU)相比,面积减少了59.7%,时钟频率提高了37.3%。 展开更多
关键词 流密码 可重构实现 非线性布尔函数 与非锥 混合极性RM
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Evolutionary Design of Boolean Functions
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作者 WANGZhang-yi ZHANGHuan-guo +1 位作者 QINZhong-ping MENGQing-shu 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第1期179-182,共4页
We use evolutionaly computing to synthesize Boolean functions randomly Byusing specific crossover and mutation operator, in evolving process and modifying search space andfitness function, we get some high non-lineari... We use evolutionaly computing to synthesize Boolean functions randomly Byusing specific crossover and mutation operator, in evolving process and modifying search space andfitness function, we get some high non-linearity functions which have other good cryptographycharacteristics such as autocorrelation etc Comparing to other heuristic search techniques,evolutionary computing approach is more effective because of global search strategy and implicitparallelism. 展开更多
关键词 Boolean function non-linearity evolutionary computing
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中国北方4个乔木属花粉-气候响应面模型研究 被引量:22
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作者 王琫瑜 宋长青 +1 位作者 孙湘君 程全国 《Acta Botanica Sinica》 CSCD 1997年第3期272-281,共10页
借鉴地质趋势面和生态响应面的方法,考虑到中国北方特殊的气候与植被状况,进行了表土花粉丰度与气候参数(年均降水量和7月均温)之间的非线性函数方程即花粉-气候响应面模型的研究。并从实际出发,选择了分布较广、生态指示意义较大的松属... 借鉴地质趋势面和生态响应面的方法,考虑到中国北方特殊的气候与植被状况,进行了表土花粉丰度与气候参数(年均降水量和7月均温)之间的非线性函数方程即花粉-气候响应面模型的研究。并从实际出发,选择了分布较广、生态指示意义较大的松属(Pinus)、桦木属(Betula)、栎属(Quercus)和云杉属(Picea)等木本植物,依数据变换方式的不同,共采用了22种建模方案来建造它们的花粉-气候响应面模型。通过对模型方程进行质量检验,选择质量最优的建模方案建模,结果表明模型对数据拟合较好,可用于中国北方定量重建古环境的研究工作中。 展开更多
关键词 花粉 气候响应面模型 表土花粉 古气候学
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重力固体潮IMF的AM-FM模型及其非线性拟合 被引量:3
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作者 吴庆畅 周挚 +2 位作者 梁虹 全海燕 王天理 《计算机工程与应用》 CSCD 北大核心 2009年第30期138-142,共5页
首先建立AM-FM数学模型,用多个相近载波的调幅信号组合描述它。利用最小二乘法对幅度调制和频率调制两个部分分别进行非线性拟合;拟合以相关系数满足一定条件为精度控制原则,拟合项数以相邻相关系数不再显著变化为判定条件。有效性检验... 首先建立AM-FM数学模型,用多个相近载波的调幅信号组合描述它。利用最小二乘法对幅度调制和频率调制两个部分分别进行非线性拟合;拟合以相关系数满足一定条件为精度控制原则,拟合项数以相邻相关系数不再显著变化为判定条件。有效性检验证明该方法切实可行。重力固体潮IMF的拟合结果表明,AM-FM数学模型可以很好地刻画重力固体潮IMF;重力固体潮是多个AM-FM信号合成的复合信号。为后续深入研究重力固体潮的AM-FM信号特征、循环平稳信号特征等性质建立了良好的数学基础。 展开更多
关键词 AM-FM模型 非线性最小二乘法 数据拟合 重力固体潮 本征模态函数(IMF)
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PUF-NLHB:基于PUF的轻量级认证协议 被引量:2
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作者 李艳 周清雷 《小型微型计算机系统》 CSCD 北大核心 2014年第4期715-719,共5页
基于GRS攻击模型设计了针对PUF-HB类协议的攻击方法,证明了该类协议不具备抵御中间人攻击的能力.在此基础上,针对PUF-HB协议的漏洞,通过加入非线性函数的方法设计了PUF-NLHB协议并给出具体的硬件实现结构,在随机oracle模型下通过向LPN... 基于GRS攻击模型设计了针对PUF-HB类协议的攻击方法,证明了该类协议不具备抵御中间人攻击的能力.在此基础上,针对PUF-HB协议的漏洞,通过加入非线性函数的方法设计了PUF-NLHB协议并给出具体的硬件实现结构,在随机oracle模型下通过向LPN问题的规约严格证明了新协议的安全性,增强了协议应对中间人攻击的能力. 展开更多
关键词 PUF HB协议 中间人攻击 非线性函数
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一种基于LS-SVM构造FLANN的热电偶非线性校正方法 被引量:6
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作者 吴德会 王晓红 《传感技术学报》 CAS CSCD 北大核心 2007年第6期1321-1324,共4页
提出一种基于最小二乘支持向量机(LS-SVM)构造函数链接型神经网络(FLANN)的方法,并根据正反馈原理将该FLANN应用於热电偶传感器非线性校正.讨论LS-SVM构造FLANN的基本原理和具体算法,给出了非线性补偿器的数学模型.与常规BP迭代算法构造... 提出一种基于最小二乘支持向量机(LS-SVM)构造函数链接型神经网络(FLANN)的方法,并根据正反馈原理将该FLANN应用於热电偶传感器非线性校正.讨论LS-SVM构造FLANN的基本原理和具体算法,给出了非线性补偿器的数学模型.与常规BP迭代算法构造的FLANN比较,该方法构造的FLANN补偿器具有如下优点:①利用LS-SVM将迭代逼近问题转化为直接求解多元线性方程,因此具有更快的速度;②整个训练过程中有且仅有一个全局极值点,确定了所构造FLANN补偿器的唯一性,提高了补偿精度.最后以Pt-Rh30-Pt-Rh6热电偶(B型)为例进行非线性校正实验,结果验证了上述结论. 展开更多
关键词 最小二乘支持向量机 函数链接型神经网络 热电偶传感器 非线性校正
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用惩罚拟协调元法分析二维N-S问题 被引量:2
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作者 刘迎曦 尚选钰 唐立民 《大连理工大学学报》 EI CAS CSCD 北大核心 1989年第5期511-518,共8页
给出构造 Navier-Stokes问题罚有限单元的拟协调元法。在处理剂次约来离散 矩阵的奇异性问题时,暂代减缩积分,利用多套函数的灵活性和秩的分析方法,进行 秩的预先设计,成功地构造出-12参三角形拟协调单元。以求解... 给出构造 Navier-Stokes问题罚有限单元的拟协调元法。在处理剂次约来离散 矩阵的奇异性问题时,暂代减缩积分,利用多套函数的灵活性和秩的分析方法,进行 秩的预先设计,成功地构造出-12参三角形拟协调单元。以求解正方形空穴流动为 例,在网格的粗的情况下,求得了雷诺数为3 000的稳定、收敛的解。在求解离散 化的非线性方程组时,将最优化法与增量-牛顿法结合使用,改善了迭代格式的适应 性能,提高了计算效率。公式推导过程和试验结果表明分忻与求解方法是有效的。 展开更多
关键词 拟协调 N-S问题 不可压缩流体
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苯乙烯-甲基丙烯酸甲酯-丙烯醛三元无皂乳液共聚合动力学研究 被引量:3
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作者 闫翠娥 程时远 《湖北大学学报(自然科学版)》 CAS 1999年第3期259-263,共5页
以苯乙烯 (St)、甲基丙烯酸甲酯 (MMA)为主单体 ,丙烯醛 (AL)为功能单体进行了无皂乳液批量共聚合 .考察了功能单体浓度、引发剂过硫酸铵ATP浓度及聚合温度对其动力学行为的影响 ,用Gamma积分函数拟合了转化率 -时间关系曲线 ,获得了聚... 以苯乙烯 (St)、甲基丙烯酸甲酯 (MMA)为主单体 ,丙烯醛 (AL)为功能单体进行了无皂乳液批量共聚合 .考察了功能单体浓度、引发剂过硫酸铵ATP浓度及聚合温度对其动力学行为的影响 ,用Gamma积分函数拟合了转化率 -时间关系曲线 ,获得了聚合过程的重要特征参数如 :平均成核速率 (Nv) ,聚合最大速率(Mv)和平稳期平均聚合速率 (Av)及成核结束和聚合进入完成期对应的转化率 .同时对聚合速率与以上各聚合参数的关系数据进行了非线性拟合 ,得到了聚合速率与以上各单个聚合参数的关系式及综合关系式 .结果表明 :聚合速率随功能单体浓度、ATP浓度及聚合温度增大而增大 ,但增大幅度逐渐减小 ;聚合过程中ATP起决定作用 . 展开更多
关键词 三元 无皂 乳液共聚合 动力学 丙烯醛 苯乙烯
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两条B样条曲线求交的高效计算方法
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作者 王永澳 吕杭汀 陈小雕 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2024年第5期687-700,共14页
曲线曲面间求交计算在CG和CAD中有着广泛的应用.牛顿法等迭代法计算效率高但需要良好的初始值;裁剪法具有良好的鲁棒性但计算效率不理想,尤其是对于相切情况的求交问题.为此,提出一种计算2条B样条曲线交点的混合方法.首先提出一种高效... 曲线曲面间求交计算在CG和CAD中有着广泛的应用.牛顿法等迭代法计算效率高但需要良好的初始值;裁剪法具有良好的鲁棒性但计算效率不理想,尤其是对于相切情况的求交问题.为此,提出一种计算2条B样条曲线交点的混合方法.首先提出一种高效的线性复杂度裁剪方法,用于获得良好的初始值;然后提出一种与导数无关且效率更高的改进的割线法,用于验证贯穿性相交情况;最后提出一个相切情况下收敛阶为2的迭代公式,其性能远优于现有的牛顿法和裁剪法.理论上,混合方法若与根隔离法相结合,可以应用于更多类型曲线间的求交问题.数值实验结果表明,与现有的同类方法相比,在贯穿情况下,所提方法的计算效率提高约10%,在相切情况下则提高约100%~300%. 展开更多
关键词 B样条曲线/曲线求交 裁剪法 线性包围法 相切 非多项式函数
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