一种基于训练数据的迭代改进核函数

To improve performance of a support vector regression, a new method for a modified kernel function is proposed. In this method, information of all samples is included in the kernel function with conformal mapping. Thus the kernel function is data-dependent. With a random initial parameter, the kernel function is modified repeatedly until a satisfactory result is achieved. Compared with the conventional model, the improved approach does not need to select parameters of the kernel function. Sim- ulation is carried out for the one-dimension continuous function and a case of strong earthquakes. The results show that the improved approach has better learning ability and forecasting precision than the traditional model. With the increase of the iteration number, the figure of merit decreases and converges. The speed of convergence depends on the parameters used in the algorithm.     

桥梁结构全息模态参数识别方法试验研究

针对传统桥梁结构健康监测中使用的接触式传感器存在数据离散性大、安装程序繁琐、难以反应桥梁结构整体状况等局限性,本文基于全息视觉传感器智能监测系统,识别结构全息几何形态在相应时空域上的振动信号,较为准确的获取结构全息图像数字化位移坐标信息,同时针对提取的振动位移进行频谱分析,获取桥梁结构的模态参数,实现对桥梁状况的基本识别。本文对一座缩尺模型桥进行试验验证,研究结果表明：全息视觉传感器智能监测系统测试结果与位移传感器测试结果吻合度较高,针对竖向荷载响应的功率谱,两种方法实测结果在低频范围内都能够较好地吻合,振型变化趋势基本一致。基于全息视觉传感器智能监测系统的桥梁形态监测真实、连续、敏感,较为准确地反映了结构在各工况下的位移变化和模态响应,后期将会进一步优化全息视觉传感器监测系统识别灵敏度,实现在各种工况激励下的高阶模态参数和结构损伤识别。     

水溶性苝醌衍生物(13-SO~2Na-DDHA)与胶体半导体(CdS)澡光 诱导电子传递过? 痰亩ρа芯?

根据非均相体系电子传递动力μ＜0(μ=E~s*/s+-E~CB)的原理,构建出相匹配的水溶性苝醌衍生物光敏剂(13-SO~2Na-DDHA)与胶体半导体(CdS)的复合体体系,? 獯忝鸱椒ǎ獬鏊侵浜捅砉劢岷铣Ｊ?K~app)为1480(mol/L)^-1。继而? τ孟孕?spincounteraction)的ESR技术,首次定量地研究了它们之间的光诱? 嫉绱莨痰亩ρВ范耸?3-SO~3Na-DDNA光敏化作用的CdS胶体半导体表? 婀饣乖ρХ匠毯退俾食Ｊ峁⑾郑诒咎逑抵蠺EMPO接受光电子的反应? 妒?,而不同于均相体系中的反应级数别虽在相同可见光照射条件下(13-SO~2Na-DDHA)复合体的光还原速率比单独CdS高约82倍,表明该水溶性光敏剂对CdS胶体半导体具有显著的敏化效果,在太阳能应用中可被用作CdS胶体半导体有效的敏化剂。