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UNIFORM ANALYTIC CONSTRUCTION OF WAVELET ANALYSIS FILTERS BASED ON SINE AND COSINE TRIGONOMETRIC FUNCTIONS 被引量:1
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作者 李建平 唐远炎 +1 位作者 严中洪 张万萍 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第5期569-585,共17页
Based on sine and cosine functions, the compactly supported orthogonal wavelet filter coefficients with arbitrary length are constructed for the first time. When N = 2(k-1) and N = 2k, the unified analytic constructio... Based on sine and cosine functions, the compactly supported orthogonal wavelet filter coefficients with arbitrary length are constructed for the first time. When N = 2(k-1) and N = 2k, the unified analytic constructions of orthogonal wavelet filters are put forward, respectively. The famous Daubechies filter and some other well-known wavelet filters are tested by the proposed novel method which is very useful for wavelet theory research and many application areas such as pattern recognition. 展开更多
关键词 wavelet analysis filter trigonometric functions analytic construction
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Numerical Solution of Green’s Function for Solving Inhomogeneous Boundary Value Problems with Trigonometric Functions by New Technique
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作者 Hamid Safdari Yones Esmaeelzade Aghdam 《Applied Mathematics》 2015年第5期764-772,共9页
A numerical technique is presented for solving integration operator of Green’s function. The approach is based on Hermite trigonometric scaling function on [0,2π], which is constructed for Hermite interpolation. The... A numerical technique is presented for solving integration operator of Green’s function. The approach is based on Hermite trigonometric scaling function on [0,2π], which is constructed for Hermite interpolation. The operational matrices of derivative for trigonometric scaling function are presented and utilized to reduce the solution of the problem. One test problem is presented and errors plots show the efficiency of the proposed technique for the studied problem. 展开更多
关键词 Numerical Technique Differential Equation Green’s function HERMITE trigonometric Scaling Wavelet Error ESTIMATE
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On Certain Properties of Trigonometrically <i>ρ</i>-Convex Functions
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作者 Mohamed Sabri Salem Ali 《Advances in Pure Mathematics》 2012年第5期337-340,共4页
The aim of this paper is to prove that the average function of a trigonometrically ρ-convex function is trigonometrically ρ-convex. Furthermore, we show the existence of support curves implies the trigonometric ρ-c... The aim of this paper is to prove that the average function of a trigonometrically ρ-convex function is trigonometrically ρ-convex. Furthermore, we show the existence of support curves implies the trigonometric ρ-convexity, and prove an extremum property of this function. 展开更多
关键词 Generalized CONVEX functions trigonometrically ρ-convex functions Supporting functions AVERAGE functions Extremum Problems
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A constructive method for approximating trigonometric functions and their integrals
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作者 CHEN Xiao-diao WANG Long-quan WANG Yi-gang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2020年第3期293-307,共15页
This paper presents an interpolation-based method(IBM)for approximating some trigonometric functions or their integrals as well.It provides two-sided bounds for each function,which also achieves much better approximat... This paper presents an interpolation-based method(IBM)for approximating some trigonometric functions or their integrals as well.It provides two-sided bounds for each function,which also achieves much better approximation effects than those of prevailing methods.In principle,the IBM can be applied for bounding more bounded smooth functions and their integrals as well,and its applications include approximating the integral of sin(x)/x function and improving the famous square root inequalities. 展开更多
关键词 Padéapproximant trigonometric function constructive method interpolation-based method two-sided bounds
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Fractional Weierstrass Function by Application of Jumarie Fractional Trigonometric Functions and Its Analysis
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作者 Uttam Ghosh Susmita Sarkar Shantanu Das 《Advances in Pure Mathematics》 2015年第12期717-732,共16页
The classical example of no-where differentiable but everywhere continuous function is Weierstrass function. In this paper we have defined fractional order Weierstrass function in terms of Jumarie fractional trigonome... The classical example of no-where differentiable but everywhere continuous function is Weierstrass function. In this paper we have defined fractional order Weierstrass function in terms of Jumarie fractional trigonometric functions. The H?lder exponent and Box dimension of this new function have been evaluated here. It has been established that the values of H?lder exponent and Box dimension of this fractional order Weierstrass function are the same as in the original Weierstrass function. This new development in generalizing the classical Weierstrass function by use of fractional trigonometric function analysis and fractional derivative of fractional Weierstrass function by Jumarie fractional derivative, establishes that roughness indices are invariant to this generalization. 展开更多
关键词 Holder Exponent Fractional Weierstrass function Box Dimension Jumarie Fractional Derivative Jumarie Fractional trigonometric function
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A trigonometric series expansion method for the Orr-Sommerfeld equation 被引量:2
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作者 Ying TAN Weidong SU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第6期877-888,共12页
A trigonometric series expansion method and two similar modified methods for the Orr-Sommerfeld equation are presented. These methods use the trigonometric series expansion with an auxiliary function added to the high... A trigonometric series expansion method and two similar modified methods for the Orr-Sommerfeld equation are presented. These methods use the trigonometric series expansion with an auxiliary function added to the highest order derivative of the unknown function and generate the lower order derivatives through successive integra- tions. The proposed methods are easy to implement because of the simplicity of the chosen basis functions. By solving the plane Poiseuille flow (PPF), plane Couette flow (PCF), and Blasius boundary layer flow with several homogeneous boundary conditions, it is shown that these methods yield results with the same accuracy as that given by the conventional Chebyshev collocation method but with better robustness, and that ob- tained by the finite difference method but with fewer modal number. 展开更多
关键词 Orr-Sommerfeld EQUATION SPECTRAL method trigonometric function PARALLEL SHEAR flow hydrodynamical stability EIGENVALUE problem
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Nearly Comonotone Approximation of Periodic Functions
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作者 G. A. Dzyubenko 《Analysis in Theory and Applications》 CSCD 2017年第1期74-92,共19页
Suppose that a continuous 2re-periodic function f on the real axis changes its monotonicity at points Yi In this paper, for each n _ N, a trigonometric polynomial Pn of order cn is found such that: Pn has the same ... Suppose that a continuous 2re-periodic function f on the real axis changes its monotonicity at points Yi In this paper, for each n _ N, a trigonometric polynomial Pn of order cn is found such that: Pn has the same monotonicity as f, everywhere except, perhaps, the small intervals. 展开更多
关键词 Periodic functions comonotone approximation trigonometric polynomials Jackson-type estimates.
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Approximate analytical solution of the Dirac equation with q-deformed hyperbolic Poschl–Teller potential and trigonometric Scarf II non-central potential
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作者 Ade Kurniawan A.Suparmi C.Cari 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期48-54,共7页
An approximate solution of the Dirac equation for a spin-1/2 particle under the influence of q-deformed hyperbolic P ¨oschl–Teller potential combined with trigonometric Scarf II non-central potential is studied ... An approximate solution of the Dirac equation for a spin-1/2 particle under the influence of q-deformed hyperbolic P ¨oschl–Teller potential combined with trigonometric Scarf II non-central potential is studied analytically. It is assumed that the scalar potential equals the vector potential in order to obtain analytical solutions. Both radial and angular parts of the Dirac equation are solved using the Nikiforov–Uvarov method. A relativistic energy spectrum and the relation between quantum numbers can be obtained using this method. Several quantum wave functions corresponding to several states are also presented in terms of the Jacobi Polynomials. 展开更多
关键词 Dirac equation q-deformed hyperbolic function Poschl–Teller potential trigonometric Scarf II potential
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The Maximum Trigonometric Degrees of Quadrature Formulae with Prescribed Nodes
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作者 Luo Zhong-xuan Yu Ran Meng Zhao-liang 《Communications in Mathematical Research》 CSCD 2014年第4期334-344,共11页
The purpose of this paper is to study the maximum trigonometric degree of the quadrature formula associated with m prescribed nodes and n unknown additional nodes in the interval(-π, π]. We show that for a fixed n,... The purpose of this paper is to study the maximum trigonometric degree of the quadrature formula associated with m prescribed nodes and n unknown additional nodes in the interval(-π, π]. We show that for a fixed n, the quadrature formulae with m and m + 1 prescribed nodes share the same maximum degree if m is odd. We also give necessary and sufficient conditions for all the additional nodes to be real, pairwise distinct and in the interval(-π, π] for even m, which can be obtained constructively. Some numerical examples are given by choosing the prescribed nodes to be the zeros of Chebyshev polynomials of the second kind or randomly for m ≥ 3. 展开更多
关键词 quadrature formula trigonometric function bi-orthogonality truncated complex moment problem
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A New Method for Calculating Inverse Involute Functions with High Precision
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作者 Zhou Ruzhong School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China 《Journal of Modern Transportation》 1997年第1期70-72,共3页
Two equations are presented for calculating inverse involute functions. Precise values can be obtained easily with an ordinary calculator.
关键词 inverse involute PRECISION trigonometric function
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信号交叉口车辆生态驾驶速度优化策略
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作者 宋成举 尹耀君 +1 位作者 范本科 昝永俊 《交通科技与经济》 2024年第6期16-22,共7页
为提高交叉口车辆通行效率,降低车辆因频繁启停造成的能耗及污染物排放,提出一种考虑排队长度动态变化的信号交叉口车辆生态驾驶速度优化策略。首先,根据排队长度预测目标车辆与排队队列的碰撞时间(TTC)。其次,将目标车辆通行策略分为... 为提高交叉口车辆通行效率,降低车辆因频繁启停造成的能耗及污染物排放,提出一种考虑排队长度动态变化的信号交叉口车辆生态驾驶速度优化策略。首先,根据排队长度预测目标车辆与排队队列的碰撞时间(TTC)。其次,将目标车辆通行策略分为匀速、加速、减速三种情况建立通行决策模型,结合改进的三角函数速度优化模型计算最优通行速度,确保车辆以平滑的速度顺利通过信号交叉口。最后,在不同排队长度场景下进行仿真实验,对比分析速度优化策略与无速度优化策略的时空轨迹。仿真结果表明,提出的速度优化策略既可以提高绿灯利用率,又可以降低目标车辆的燃油消耗,相较于无速度优化策略驾驶,燃油消耗最多可降低19.5%,对信号交叉口处车辆生态驾驶有积极作用。 展开更多
关键词 智能交通 通行策略 速度优化 三角函数模型 排队队列 碰撞时间
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基于薄板样条径向基函数的复合材料层合板自由振动分析
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作者 宋薇薇 项松 +2 位作者 赵锐 赵为平 郭晗 《计算力学学报》 CAS CSCD 北大核心 2024年第5期954-962,共9页
基于复合材料层合板的三角剪切变形理论,推导了对称复合材料层合板的控制微分方程。利用基于薄板样条径向基函数的无网格配置方法离散的控制微分方程,预测了对称复合材料层合板的自由振动行为。计算了不同材料参数和层合板几何参数的固... 基于复合材料层合板的三角剪切变形理论,推导了对称复合材料层合板的控制微分方程。利用基于薄板样条径向基函数的无网格配置方法离散的控制微分方程,预测了对称复合材料层合板的自由振动行为。计算了不同材料参数和层合板几何参数的固有频率,并与文献结果进行了比较。还研究了节点排布、模量比和边厚比对固有频率的影响。结果表明,本文结果与文献结果具有较好的一致性,节点数量越大,无量纲频率对网格分布越不敏感,固有频率随着边厚比和模量比的增加而增加。通过数值实验,证明了用薄板样条径向基函数离散的三角剪切变形理论对对称复合材料层合板的自由振动分析具有较高的数值精度和良好的收敛性。 展开更多
关键词 三角剪切变形理论 复合材料层合板 自由振动 薄板样条径向基函数 固有频率
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基于层次分析法(AHP)与模糊综合评价相结合的油区输电线路运行状态评价
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作者 李化龙 孙赟 +2 位作者 李思琦 张彩婷 鲁云云 《科技通报》 2024年第2期25-29,共5页
油田快速建产对油区电力系统可靠性提出更高的要求,架空输电线路的运行状态评价是保障电路安全可靠运行的重要环节。为此,本文提出了基于层次分析法与模糊综合评价相结合的油区输电线路运行状态评价方法。通过选取相关评价指标,搭建输... 油田快速建产对油区电力系统可靠性提出更高的要求,架空输电线路的运行状态评价是保障电路安全可靠运行的重要环节。为此,本文提出了基于层次分析法与模糊综合评价相结合的油区输电线路运行状态评价方法。通过选取相关评价指标,搭建输电线路运行状态评价体系,采用层次分析法和模糊综合评价相结合的方式,对输电线路展开综合评价。实验结果表明,该条输电线路运行状态处于“注意”,验证了所提出的状态评价方法的有效性。 展开更多
关键词 输电线路 状态评价 层次分析法 模糊综合评价 三角梯形函数
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探讨一类函数的性质及其应用
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作者 范文青 《科技资讯》 2024年第13期236-239,共4页
首先讨论了初等函数f(x)=x^(a)sinx^(b)在x=0处的连续性和可微性,给出了定理1和定理2及其证明。其次讨论了函数f(x)=x^(a)sinx^(b)在无穷远处的性质,给出定理3函数f(x)在[1,+∞)上一致连续的充要条件,并在此基础上给出一个推论和两个性... 首先讨论了初等函数f(x)=x^(a)sinx^(b)在x=0处的连续性和可微性,给出了定理1和定理2及其证明。其次讨论了函数f(x)=x^(a)sinx^(b)在无穷远处的性质,给出定理3函数f(x)在[1,+∞)上一致连续的充要条件,并在此基础上给出一个推论和两个性质。最后利用这些性质,探讨函数f(x)=x^(a)sinx^(b)在不同领域的一些应用,给出定理4、定理5和定理6并加以证明。其中,包括函数一致连续性充分条件的讨论、函数在一点处4个Dini导数的任意性,以及函数f(x)在拓扑学中的一个应用。 展开更多
关键词 三角函数 幂函数 初等函数 一致连续
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基于解析法的空间角向孔镗削工艺尺寸转换研究
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作者 杨欢 鞠录岩 +3 位作者 孙若文 张维琨 张耀武 郭龙龙 《制造技术与机床》 北大核心 2024年第9期155-160,共6页
空间角向孔作为行星轮系旋转作动器中的重要结构特征具有很高的加工精度。镗削时必须根据图纸设计尺寸得到准确的镗削工艺尺寸,以便准确定位。文章系统地对双角度、三角度空间角向孔镗削过程、工艺尺寸转换进行了研究,使用图解法、解析... 空间角向孔作为行星轮系旋转作动器中的重要结构特征具有很高的加工精度。镗削时必须根据图纸设计尺寸得到准确的镗削工艺尺寸,以便准确定位。文章系统地对双角度、三角度空间角向孔镗削过程、工艺尺寸转换进行了研究,使用图解法、解析法推导出对应的计算公式,拓展了工艺尺寸转换方法。利用解析法得到的计算公式,实现利用空间角向孔与工艺钢球相对尺寸及空间角向孔角度尺寸,得到所需的镗削工艺尺寸,降低了工艺尺寸转换难度,提高了空间角向孔的镗削效率。同时结合Python编程语言,编写出一套工艺尺寸计算软件,验证了推导公式的有效性和准确性。 展开更多
关键词 空间角向孔 图解法 解析法 立体几何 三角函数
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基于SOLO分类理论的高考三角函数试题评析——以2023年4套高考数学试卷为例
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作者 王允 张盼 马迎宾 《教育测量与评价》 2024年第2期71-84,共14页
利用SOLO分类理论对全国甲卷理科卷、全国乙卷理科卷、全国Ⅰ卷和全国Ⅱ卷4套试卷的三角函数试题进行统计分析,发现4套试卷对于三角函数的考查内容全面,题型结构稳定。一级知识的考查频数从高到低排序依次为:三角函数的概念与性质、解... 利用SOLO分类理论对全国甲卷理科卷、全国乙卷理科卷、全国Ⅰ卷和全国Ⅱ卷4套试卷的三角函数试题进行统计分析,发现4套试卷对于三角函数的考查内容全面,题型结构稳定。一级知识的考查频数从高到低排序依次为:三角函数的概念与性质、解三角形、同角三角函数的基本关系式、三角恒等变换;二级知识中考查最多的是余弦定理。试题整体处于中阶思维水平,思维能力划分清晰,有着明显的SOLO梯度。具体来看,多点结构水平试题最多,关联结构水平试题分值最高,整体思维考查处于多点结构水平和抽象拓展结构水平之间。这提示教师要夯实三角函数基础知识,加强知识的变式训练;构建知识网络,重视主题—单元整体教学;设计多思维水平试题,实现因材施教。 展开更多
关键词 高考数学 试题分析 SOLO分类理论 三角函数 思维水平 思维层次
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基于三角函数的加权平均全景环视图像融合方法
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作者 豆志伟 王晓原 +1 位作者 韩俊彦 王瀚卿 《传感器与微系统》 CSCD 北大核心 2024年第4期144-148,共5页
全景环视(AVM)系统是减小汽车盲区的有效工具,针对已有AVM图像中存在的拼接缝以及拼接误差等问题,提出了两种依据像素坐标的三角函数值计算权值的像素级图像融合方法。对于短距AVM图像的融合,提出了一种以融合区域像素坐标的正弦/余弦... 全景环视(AVM)系统是减小汽车盲区的有效工具,针对已有AVM图像中存在的拼接缝以及拼接误差等问题,提出了两种依据像素坐标的三角函数值计算权值的像素级图像融合方法。对于短距AVM图像的融合,提出了一种以融合区域像素坐标的正弦/余弦值为融合权重的图像融合方法,命名为“时钟扫描图像融合法”;对于长距AVM图像的融合,提出了一种依据正切函数曲线拟合矩形融合区域,并利用正切函数系数构造权值区间确定各像素权重系数的方法,以同时顾及3条融合边界,称之为“tan—加权图像融合法”。研究结果表明,两种图像融合方法在消除相邻图像之间的拼接缝、提升融合图像的清晰度等方面具有良好效果,可实现融合区域的平滑过渡。 展开更多
关键词 图像融合 加权平均 全景环视图像 三角函数 拼接缝
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三角级数的解析求解与应用
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作者 陶正奎 王玉凤 +3 位作者 施逸洋 王越超 孙嘉泽 李喜彬 《高等数学研究》 2024年第1期108-112,共5页
利用欧拉公式,将三角级数可以转化为幂级数,进而利用泰勒展开等手段,得到幂级数的收敛函数.利用三角函数的周期性,还可以得到一些级数的解析结果.通过几个例题,可以加深对此类问题的理解.
关键词 定积分 三角函数 级数 特殊函数
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泰勒公式在复杂函数极限求解中的应用
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作者 张曹煦 卢爽 《高等数学研究》 2024年第5期1-2,12,共3页
本文主要研究泰勒公式在求极限的题目中的应用.总结了利用泰勒公式求极限的一般原则和注意点,讨论了含诸如复合函数和幂指函数等复杂极限的求解方法,并举例说明其应用.
关键词 泰勒公式 极限问题 复合三角函数
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基于空间解析几何模型的多波束测线研究——以渤海某海域为例
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作者 赵帅 方韵雯 +3 位作者 李建林 毕英峰 李洪强 刘泽宇 《计算机应用文摘》 2024年第11期138-140,143,共4页
以渤海某海域为例,文章主要研究了多波束测线测量方法。在对覆盖宽度、重叠率及测线布置等问题进行深入分析的基础上,综合应用了空间解析几何模型与平面解析几何模型,使用迭代算法构建了海水深度、坡角与覆盖宽度、重叠率之间的模型。
关键词 多波束测深系统 三角函数变换 空间解析几何
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