三维时—空域曲面拟合与叠加

多项式拟合技术在提高信噪比的同时基本上不降低资料的分辨率,但该法以往仅适用于二维拟合。本文提出了三维时—空域曲面拟合与叠加方法,给出了数理推导和实现步骤,利用三维复合正交基的可分解性,实现了线性拟合、双曲拟合、挠曲拟合的分离和复合,完成了二维拟合向三维拟合的拓展,使多项式拟合方法适用于三维地震资料处理。采用该方法对实际三维地震资料在共炮检距域进行三维曲面拟合与叠加,得到相应的叠加剖面。处理结果表明,该方法能有效地提高地震资料的信噪比和分辨率。

基于亚像素边缘的摄像机标定板特征提取算法

目的在视觉测量领域,摄像机的标定精度是最终测量精确度的决定性因素,为了提高标定板特征的提取精度,提出一种基于亚像素边缘的提取方法。方法针对圆点标定板,首先采集标定板图像,对图像进行处理,获取像素级别边缘,然后以边缘像素点为中心,取3×3的数字窗口计算梯度方向,在梯度方向上进行像素点灰度的双曲正切拟合,获取亚像素级别边缘,最后对亚像素边缘按照圆形进行拟合,求得圆心坐标。结果实验表明算法的分辨率达到0.03个像素,精度可达0.1个像素。结论该算法具有稳定可靠,精度高,运算速度快等特点,能够应用于图像拼接和分割,特征提取和摄像机标定等领域。

影响B50A224钢韧脆转变温度的因素

针对B50A224钢系列温度冲击试验数据,首先采用不同的方法进行拟合,通过比较得出双曲正切函数拟合得到的曲线更符合冲击功及脆性断面率随温度变化的规律,且能降低因冲击试样不均匀对由拟合曲线求得的韧脆转变温度的影响。然后分析了材料显微组织对韧脆转变温度的影响,找出了造成B50A224钢冲击试验出现异常数据的原因。最后通过改进热处理工艺,降低了该钢的韧脆转变温度,提高了其在低温下的抗冲击能力。

Effect of Leachate Recirculation on Settlement and Leachate Generation of Municipal Solid Waste from Landfill Lysimeter

The objectives of this study are to determine the settlement and leachate generation from landfill lysimeters of municipal solid waste. Two identical lysimeters with a diameter and height of 0.70 m and 2.40 m were prepared, respectively. The lysimeters were operated with and without leachate recirculation treatment. The settlement and leachate generation were quantified daily. The analysis of settlement was conducted by using hyperbolic function and curve fitting. Based on the experiments result, it is observed that garbage pile settlement in lysimeter treated with leachate recirculation （L-2） is higher than without recirculation treatment （L-1） as showed by the hyperbolic function and curve fitting result. The ultimate settlement （S_wlt） for L-1 and L-2 that used hyperbolic function were 0.487 m and 0.53 m, respectively. Meanwhile （S_wlt） that using curve fitting resulted 0.74 m, and 0.68 m for L-1 and L-2, respectively. The lysimeter which treated with leachate recirculation treatment showed a higher leachate height than without the treatment.