查询词典 cosine

In this project, we study the theory of higher order differential equations in Banach spaces and related topics. We solve an open problem put forward by two American Mathematicians and two Italian Mathematicians concerning wave equations with generalized Weztzell boundary conditions, introduce an existence family of operators from a Banach space $Y$ to $X$ for the Cauchy problem for higher order differential equations in a Banach space $X$, establish a sufficient and necessary condition ensuring $ACP_n$ possesses an exponentially bounded existence family, as well as some basic results in a quite general setting about the existence and continuous dependence on initial data of the solutions of $ACP_n$ and $IACP_n$. We set up quite a few multiplicative and additive perturbation theorems for existence families governing a wide class of higher order differential equations, regularized cosine operator families, regularized semigroups, and solution operators of Volterra integral equations, obtain classical and strict solutions having optimal regularity for the inhomogeneous nonautonomous heat equations with generalized Wentzell boundary conditions, gain novel existence and uniqueness theorems,which extend essentially the existing results, for mild and classical solutions of nonlocal Cauchy problems for semilinear evolution equations, present a new theorem with regard to the boundary feedback stabilization of a hybrid system composed of a viscoelastic thin plate with one part of its edge clamped and the rest-free part attached to a visocelastic rigid body. Also we obtain many other research results.

在本研究中，我们对Banach空间中的高阶算子微分方程的理论以及相关理论进行了深入研究，解决了由美国和意大利的四位数学家联合提出的一个关于广义Wentzell边界条件下的波动方程适定性的公开问题，恰当地定义了Banach空间中的高阶算子微分方程Cauchy问题的算子存在族及唯一族，建立了齐次和非齐次高阶算子微分方程Cauchy问题适定性的判别定理，获得了关于高阶退化算子微分方程的算子存在族、正则余弦算子族、正则算子半群、Volterra积分方程解算子族的乘积扰动和混合扰动定理，得到了关于以依赖于时间的二阶微分算子为系数的一大类非自治热方程非齐次情形下的时变广义Wentzell动力边值问题的古典解、严格解的最大正则性结果，获得了半线性发展方程非局部Cauchy问题广义解和经典解存在唯一的判别条件，从实质上推广了现有的相关结果；得到了一部分边缘固定而另一部分附在一粘弹性刚体上的薄板构成的混合粘弹性系统的边界反馈稳定化的新稳定化定理，还建立了一系列其他研究结果。

With this important concept which the reads of wattmeter was equal to the product of the effective value of the voltage across the potential coil, the effective value of the current flowing in the current coil, and the cosine of the phase-angle between the current and the voltage. It was speciled with some examples to determine the phase-angle measured between line voltage, line current in different connection.

围绕有功功率表的读数等于该功率表电压线圈所接电压的有效值、电流线圈所通过的电流的有效值以及电压与电流相位差余弦的乘积这一重要的概念，用实例说明在不同的接线情况下如何利用各电量的相量关系来确定所测的线电压、线电流之间的相位差角。

The binary coding of cosine eliminates zeroth order diffraction theoretically, and can generate high pixel hologram.

余弦二值编码方法从理论上消除了零级衍射，可以制作像素较多的全息图。

In this method, the sine, cosine signal is converted by three line autosyn and its output is a binary code based on AD2S83. The measurement datum can be read and displayed by computer.

着重研究了自整角机的三相信号通过隔离转换电路转换成正、余弦信号，输入到高精度AD2S83的轴角／数字转换电路转换成二进制数字信号，供给计算机系统读数显示。

Two types of coefficients transforms are compared,The minimal number of nonzero digitals called Canonic Sign Digital and common substructure sharing mode are used to improve performance of raise cosine shape filter.

利用Canonic Sign Digit表示定点数并且实现高效的移加运算，实现定点数乘法可以极大减少硬件资源[1]，利用滤波器邻近抽头系数的特点进行相同项的合并共享进一步精简硬件资源[2]。

The horizontal and vertical first derivatives of magnetic anomalies of an infinite cylinder are calculated by the cosine transform method, in which the maximum errors are -028 nT/m and 047nT/m, respectively and the percent errors are generally within -357%～327% and -194%～188%, respectively except several data of the boundary and part are bigger because of remains of Gibbus effect. The calculating curve and theoretical curve are approximately coincident, and there is no influence by effective magnetic dip angle in computing.

利用余弦变换法计算的无限长水平圆柱体磁异常水平和垂向一阶导数的最大误差分别为-028 nT/m、047 nT/m；水平一阶导数的误差一般在-357%～327%之间，垂向一阶导数的误差一般在-194%～188%之间；计算的磁异常一阶导数值与理论值大致重合，而且不受有效磁化倾角的影响。

In model experiments, we find that the deviation of the first derivative calculated by Fourier transform is very large to comparing with the theoretical derivative, but the fitting effect of the derivative of anomalies calculated by cosine transform is very good. The calculation accuracy of data are all very high except that errors of several data on the boundary are large because of the residual Gibbus effect induced by finite truncation of gravity anomalies. Errors are -009%～5%.

模型实验中发现，用Fourier变换计算的一阶导数与理论导数偏差很大，而余弦变换计算的导数与理论异常导数拟合效果非常好，除边界几个数据因重力异常的有限截断产生的吉布斯效应残留使误差较大外，数据的计算精度均很高，误差为-009%～5%。

The horizontal and vertical first derivatives of magnetic anomalies of an infinite cylinder are calculated by the cosine transform method, in which the maximum errors are -0.28 nT/m and 0.47nT/m, respectively and the percent errors are generally within -3.57%~3.27% and -1.94%~1.88%, respectively except several data of the boundary and part are bigger because of remains of Gibbus effect. The calculating curve and theoretical curve are approximately coincident, and there is no influence by effective magnetic dip angle in computing. But the errors with the Fourier transform method are -10.62nT/m and 14.42nT/m, there is large departure between the calculating curve and theoretical curve and evident influence by effective magnetic dip angle in computing.

利用余弦变换法计算的无限长水平圆柱体磁异常水平和垂向一阶导数的最大误差分别为-0.28nT/m、0.47nT/m；水平一阶导数的误差一般在-3.57%~3.27%之间，垂向一阶导数的误差一般在-1.94%~1.88%之间；计算的磁异常一阶导数值与理论值大致重合，而且不受有效磁化倾角的影响而Fourier变换法计算的水平和垂向一阶导数最大误差分别为-10.62nT/m、14.42nT/m，计算曲线与理论曲线偏离大，受磁化倾角的影响也较大。

For fast orthogonal transformation algorithm, the paper carries out detailed research and analysis. In terms of many transform coding, it put forward these four rapid transformation algorithms which are Discrete Cosine Transform, Discrete Fourier Transform, Harr Transform, Walsh-Handmaid Transform, and analysis of these fast algorithms in image compression applications.

对于正交变换的快速算法本文进行了详细的研究与分析，并根据各种变换编码，提出了离散余弦变换、离散傅立叶变换、Harr变换、Walsh-Hadamard变换这四种变换的快速算法，并分析了这些快速算法在图象压缩中的应用。

The approximating error is effectively solved by using the transformation of sine and cosine functions, which is caused by the incontinuous transformation from 360° to 0°.

通过正弦和余弦函数变换的方法，有效解决了360°~0°转换不连续性引起的逼近误差，提高了估计精度，并给出了算法的具体实现步骤。

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。