特征函数

Three intersection functions,such as adjacent node set,node-arc angle set and connected node set,were presented,and based on the shortest path method proposed by Dijkstra,a road guide sign model was built by using the intersection functions.

结合路网的拓扑结构，定义了用于确定指路标志的状态函数集，给出了3个描述路网拓扑特征的交叉口函数：邻近结点集、结点-弧段夹角集和连通结点集，基于Dijkstra最短路径的思想，运用交叉口函数建立了城镇指路标志的标识模型：以待标识城镇为中心，在城镇的影响区域内，通过向外搜索交叉口邻近结点集来确定指路标志的设置，并使每个结点上标识的路径都是最优的。

In order to represent accurately and concisely the changing characteristics of one-dimensional spectrum density function in the chatter development. This thesis, for the first time, proposes the Edgeworth asymptotic expansion formulas of spectral density. A detailed proof is given. Some new statistic including spectral skewness, spectral kurtosis and spectral cumulants are proposed.

为了准确、简洁地表达一维谱密度函数在切削颤振建立过程中的变化特征，论文首次建立了一维谱密度函数的Edgeworth渐近谱展开式，给出了详细的证明；并由此提出了"谱偏态系数"、"谱峰态系数"和"谱累积量函数"等新的谱统计量。

By solving the SturmLiouville eigen-equation in the barycentric coordinate, the generalized sine and cosine functions in the triangular domain are constructed. Properties of these functions are systematically investigated by visualization and theoretical derivation.

本文通过求解重心坐标下的Sturm-Liouville特征方程，构造出了三角区域的广义正弦函数和广义余弦函数，并通过可视化与理论推导相结合的方法系统的研究了这两组函数的性质。

By solving the Sturm-Liouville eigen-equation in the barycentric coordinate, the generalized sine and cosine functions in the triangular domain are constructed. Properties of these functions are systematically investigated by visualization and theoretical derivation.

本文通过求解重心坐标下的Sturm-Liouville特征方程，构造出了三角区域的广义正弦函数和广义余弦函数，并通过可视化与理论推导相结合的方法系统的研究了这两组函数的性质。

Firstly, the approach formulates a cost functional to turn the inverse problem into a constrained minimization problem according to least squares criterion, then the resulting constrained minimization problem is transformed into an unconstrained minimization problem by using a penalty function technique, and then the closed Fr chet derivatives of the Lagrange function with respect to the properties are derived based on the calculus of variations, finally, one can solve the resulting problem by using any gradient-based algorithm and the finite-difference time-domain method.

该方法首先以最小二乘准则构造目标函数，将逆问题表示为约束最小化问题；接着应用罚函数法转化为无约束最小化问题；然后基于变分计算导出闭式的拉格朗日函数关于特征参数的Fr chet导数；最后借助梯度算法和时域有限差分法迭代反演德拜模型参数。

This paper proposes a robust filter function, called trilateral filter function, to filter the noises in the domains of surface curvature, normal and position at each sample point while the local surface is fitted in a quadratic form. By optimizing the filtering result of curvature tensor, our approach is capable of preserving the feature on the target model.

通过在扫描模型每个采样点处拟合一个二次型曲面，设计了一个鲁棒的滤波函数--三边滤波函数；应用该函数分别对模型表面上每个点的法线、曲率和位置进行滤波；通过对曲率的滤波结果进行优化，可有效地保持三维模型表面上的特征。

Theoretical analysis proves that,when the pixel number,pixel size and reconstructed wavelength of the hologram are certain,computer simulated algorithms of Fresnel diffraction integral fall into convolution algorithm,angular spectrum algorithm and direct Fourier trans...

通过对相位函数局域空间频率的分析，给出了判定算法适用范围的特征再现距离，并分析得出，再现距离大于特征再现距离时，适合用卷积法；小于特征再现距离时，适合采用角谱法；等于特征再现距离时三种方法都适用。

This paper establishes cubic spline function, analyzes subsection curve function and curve slope and curvature, at last decides to place the curve especial points which can be obtain easement curve length and other line parameters, such as the ZH point (end of line and beginning of transition curve), the HY point (end of transition curve and beginning of circular curve), the QZ point, the YH point (end of circular curve and beginning of transition curve), the HZ point (end of transition curve and beginning of line).

针对公路平面线形的8种组合类型，其线形元素特征则由最基本的直线、圆曲线、缓和曲线组成的特点，解析三次样条函数模型，得分段曲线函数、曲线斜率、曲率，从而确定曲线特征点（直缓ZH点、缓圆HY点、曲中QZ点、圆缓YH点、缓直HZ点）位置，进而得到曲线缓和曲线长度及其他线形参数。

For meeting the needs of automated real-time dynamic monitoring of heavy fog events by means of a weather satellite remote-sensing technique for specialized meteorological services like military operations and highway traffic, the paper presents a systematic study of spectral characteristics of visible and infra red light, the textures and dynamic dispersals of fogs on satellite imagery in the context of theory on the transmission of atmospheric radiation, thereby revealing their abruptness, waviness and mass-like features, which, in combination with a synthetic technique for cloud/fog maps of multi-channel remote-sensing spectra are used to set up a model for automatic separation of fogs from clouds based on the integrative application of spectral features and texture structures, for which are constructed corresponding discfiminant functions and criteria, and on this basis prepared is a"system for remotely-sensing monitoring of low cloud and heavy fog"which has been used for tests, with the main conclusions shown as follows.

本文针对军事和高速公路等专业气象服务中应用气象卫星遥感技术对大雾进行自动化实时动态监测的实际需要，从大气辐射传输理论入手，系统地研究了气象卫星遥感图像上云雾的可见光和红外光谱特征、纹理结构特征和大雾的消散动态特征，揭示了雾的突发性、波动性和团状雾特性，通过研究多通道遥感光谱的云雾图像合成技术，建立了综合应用光谱特征和纹理结构特征的云雾自动分离模型，给出了相应的判别函数和判别准则，研制了&低云大雾遥感监测系统&，并进行了实际应用试验。

This method first maps training data into a high dimensional feature space through kernel function concept in Support Vector Machine and constructs orthogonal space in the feature space. Then it maps the data from feature space into the orthogonal space and computes Fisher criterion based global orthogonal discriminants.

首先应用支持向量机中核函数的概念，将样本隐式地映射到特征空间，然后构造特征空间的正交空间，再将特征空间样本映射到特征空间的正交空间，求解基于Fisher的全局正交鉴别矢量集。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷