The important issue of the research of yield curve is to discover the quantitative relation between yield to maturity and years to maturity by the analysis of the past trading data so as to calculate the theoretical yield to maturity and predict the forward interest rate of any years to maturity in the future 研究国债收益率曲线重点要解决的问题是通过对国债交易的历史数据的分析，找出国债收益率与到期期限之间的数量关系，从而能够准确地推算拟合曲线上任意点的理论收益率，并预测出将来任意给定期限的国债所对应远期利率。
The results indicated that the dimension , shape and purity of base material could meet the functional demand of solid lubricant ; the thermal decomposition temperature of ptfe resin exceeds 400 c , but organic and inorganic packing filler added in ptfe made the water absorption rate of composite material increased , melting temperature and decomposition temperature decreased , in the meanwhile oxidative decomposition reaction was accompanied ; polar groups such as c = o , c - o - c and so on in the carbon fiber surface is advantageous to increase compatibility with other components and interlayer shearing strength ; uniform design experimental method could help to find the relationship between formula and frictional property by relatively small tests . the developing trend of each formula ' s friction coefficient could be showed by fitting curve ; the friction coefficient with no copper powder or graphite in formula was relatively big . this fact showed that copper powder and graphite should be used cooperatively ; it was found that when the ratio of copper powder to graphite by weight is 15 : 60 , 30 : 30 - 40 and 60 : 15 - 30 respectively , the friction coefficient was relatively small . the degree of crystallinity of pure ptfe reached maximum by air cooling and the abrasion loss also reached maximum among three ones ; at the same time , the abrasion loss of solid lubricant sample was also the biggest among three ones ; when solid lubricant matched with 45 # steel axle or gcrl5 steel axle , lubricant transfer film could be formed on metal surface , thus direct contact between the surface of metal friction pair rings was reduced . their working life was elongated extremely ; there was mainly much graphite , a little ptff , moo3 , feso4 , cus and so on in lubricant transfer film 试验结果表明：所选原料的尺寸、形状及纯度可满足固体润滑剂的性能要求；聚四氟乙烯树脂热分解温度超过400 ，但在ptfe中加入无机填料会使复合材料吸水率提高，熔融温度及分解温度降低，且伴有氧化分解反应；碳纤维表面含有c = o及c - o - c等极性基团，有利于提高其与其它组分的相容性，提高层间剪切强度；均匀设计试验方法能够用较少的试验次数找出配方与摩擦性能间的关系，拟合曲线基本能表示各配方的摩擦系数发展趋势；配方中不加铜粉或不加石墨，其摩擦系数均较高，说明铜粉和石墨应该配合使用；当铜粉15份、石墨60份时，铜粉30份、石墨30 - 40份时，铜粉60 、石墨15 - 30份时，摩擦系数均具有较低值；纯聚四氟乙烯树脂在空气冷却时结晶度最大，磨损量也是三者中最大的；同时，固体润滑剂试样在空气冷却时的磨损量也是三者中最大的：不论是固体润滑剂与45 #钢轴配副或是固体润滑剂镶嵌入铜套后与gcr15钢轴配副，在金属表面均可形成润滑转移膜，从而减少金属摩擦副表面间的直接接触，大大延长其使用寿命;转移膜中主要含有较多的石墨、少量聚四氟乙烯、 moo 。
( 3 ) aiming at the deficiency of present methods of network traffic anomaly , this paper proposes a new scale - adaptive detection mechanism . by means of wavelet packet decomposition , our method has the same detective ability to middle and high frequency as well as low frequency anomaly ; by means of reconstruct the wavelet packet 该方法利用层叠模型从本质上体现流量性质的特点,选择用多分辨分析( mra )和小波变换模极大( wtmm )估计层叠模型的判定条件作为检测依据,通过对拟合曲线误差的估计来判定异常的发生。
A sub - circuit model for vdmos is built according to its physical structure . parameters and formulas describing the device are also derived from this model . comparing to former results , this model avoids too many technical parameters and simplify the sub - circuit efficiently . as a result of numeric computation , this simple model with clear physical conception demonstrates excellent agreements between measured and modeled response ( dc error within 5 % , ac error within 10 % ) . such a model is now available for circuit simulation and parameter extraction 从vdmos的物理结构出发建立子电路模型,进而导出描述其交直流特性的参数及模型公式.相对以往文献的结果,该模型避免了过多工艺参数的引入,同时对子电路进行了有效的简化.在参数提取软件中的加载结果表明,该模型结构简单,运算速度快,物理概念清晰,拟合曲线与测试数据符合精度高(直流误差5以内,交流误差10以内) ,适于在电路模拟及参数提取软件中应用
Abstract : a sub - circuit model for vdmos is built according to its physical structure . parameters and formulas describing the device are also derived from this model . comparing to former results , this model avoids too many technical parameters and simplify the sub - circuit efficiently . as a result of numeric computation , this simple model with clear physical conception demonstrates excellent agreements between measured and modeled response ( dc error within 5 % , ac error within 10 % ) . such a model is now available for circuit simulation and parameter extraction 文摘:从vdmos的物理结构出发建立子电路模型,进而导出描述其交直流特性的参数及模型公式.相对以往文献的结果,该模型避免了过多工艺参数的引入,同时对子电路进行了有效的简化.在参数提取软件中的加载结果表明,该模型结构简单,运算速度快,物理概念清晰,拟合曲线与测试数据符合精度高(直流误差5以内,交流误差10以内) ,适于在电路模拟及参数提取软件中应用
This process is as follows : firstly , the data of different section contour and of section line have been obtained by reverse - engineering ; secondly , non - uniform b - spline approximation algorithm is used to fit the discrete data ; then the data have been optimized and reduced by adopting adaptive sampling of key points of the fitted curve based on vertical distance , sequently the adaptive sampling data is transformed into the format of the . ibl file of the famous 3 - d design software pro / e . therefore we reconstruct the surface and a model is generated ; lastly , the effectiveness of the adopted algorithm and modeling approach are demonstrated by the experiments 建模型的过程中，首先运用逆向工程测量方法，获得曲面物体上不同截面轮廓线的测量数据点列，接着对测量数据点进行平滑处理，用最小二乘法求解基于数据点列的控制多边形，以非均匀三次b样条曲线拟合截面轮廓曲线；然后利用基于垂距的数据采样算法，对拟合曲线上的数据点进行重新采样，达到优化数据点的分布及减少描述曲线数据量的目的。
Firstly the phase is extracted from interferogram by filtering and displacing frequency spectrum . then the wavefront and the line integral density are recovered by using fft or polynomial fitting method . lastly the radial local density distribution is calculated from the fitting curve of line integral density by the abel inversion 首先对干涉图进行频谱滤波，用频谱移频法从干涉图中提取相位，然后用快速傅立叶变换或多项式拟合实现波面重建，计算线积分密度，再利用abel积分变换从线积分密度的拟合曲线中反演径向体密度分布。
Study several algorithms : localization underground target algorithm base on step threshold of block energy 、 localization underground target algorithm base on the best automatic curve fitter 、 recognition underground metal target algorithm base on phase of target echo . test above algorithms using signal acquired on field 具体研究了:基于块能量阶梯阈值的目标检测定位方法、基于自动最佳拟合曲线的波速测定和目标定位方法、基于目标回波峰值相位特征的地下金属目标识别方法。
During the past decades , some researchers , such as : bezier , kj . versprile , deboor and cox , etc . had made great progress in the filed of constrained b - spline curve and surface fitting . in this article the method of constrained b - spline curve was introduced , which is used to figure out the control vertexes . using this interpolation method we can calculate every points of a uniform b - spline 并且分析了在各种端点情况下，在重节点的情况下，如何反算控制多边形的顶点；如何在求出控制多边形顶点之后，插值计算b样条拟合曲线上的每一点；并通过结合双尾船的型线，采用visualc + +和autocad2002为平台，分别编制了相应的软件，对提供的型值做出绘图处理，取得了良好的效果。
