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distribution functions, i.e. lognormal, Weibull, Gamma and Pearson V were used to fit the complete set of PM10 mass concentration in Changsha. The method of moment and the method of maximum likelihood were used to estimate the parameters. Two parameters exponential distribution was used to fit the high concentration of PM10. The results show that Gamma distribution is the best one to represent......
, Beijing 100088 , China)Abstract:Fe-Ni-Y2O3 nanocomposites with uniform distribution of fine oxide particles in the gamma FeNi matrix were successfully fabricated via solution combustion followed......
RADARSAT图象滤波的研究 杜培军1 (1.中国矿业大学,测绘与空间信息工程研究所,江苏,徐州,221008) 摘要:在分析SAR图象斑点噪声特性和主要滤波算法的基础上,将中值滤波,均值滤波,LEE与增强LEE滤波,FROST与增强FROST滤波,KUAN滤波,GAMMA滤波,小波软阈值滤波等算法应用于RADARSAT图象滤波,以平滑指数和边缘保持指数等作为评价指标,对各种方法进行了比较.结果表明,中值,均值滤波算法的效果较差,而各种自适应滤波算法和小波软阈值算法是最有效的. 关键词:雷达遥感; RADARSAT; 斑点噪声; 滤波; [全文内容正在添加中] ......
reflectance and three-dimensional (3D) thermoluminescence (TL) emission spectrum after 60Co gamma ray irradiation were investigated. The characteristic 3D TL emission bands at about 425, 481 and 573 nm... wavelength range. The TL-dose response of the Zn(BO2)2:Dy polycrystalline powder sample to gamma ray radiation in the range from 1 to 100 Gy at clinical dose levels was almost linear. The experimental......
glasses(K509 and K9) were irradiated by gamma rays with a dose range from 10 to 1000 kGy. The results showed that E’ center, oxygen deficient center(ODC) and non-bridging oxygen hole center(HC1 and HC2) were induced in K9 and K509 glasses after radiation. The concentrations of all color centers presented an exponential growth with the increase of the gamma dose. Moreover, the concentration of HC1......
glasses(K509 and K9) were irradiated by gamma rays with a dose range from 10 to 1000 kGy. The results showed that E’ center, oxygen deficient center(ODC) and non-bridging oxygen hole center(HC1 and HC2) were induced in K9 and K509 glasses after radiation. The concentrations of all color centers presented an exponential growth with the increase of the gamma dose. Moreover, the concentration of HC1......
composed of elongated gamma grains and lamellar colonies. Heat treatments were conducted on the as-rolled sheets. The results show that the microstructures with different sizes and grain boundary... on their microstructures. The microstructures can be controlled by appropriate thermomechanical process and heat treatments. There are four specific morphological features in γ-TiAl alloys: near gamma (NG), duplex (DP......
基于随机载荷和强度退化的可靠性灵敏度分析杨周1,郭丙帅1,张义民1,2,顾洛玮11. 东北大学机械工程与自动化学院2. 沈阳化工大学装备可靠性研究所摘 要:针对随机载荷和强度退化所引起的动态可靠性问题,将载荷和强度同时考虑成随机过程,利用顺序统计理论得出最大等效载荷,利用Gamma过程来描述机械零件的强度退化过程,并对零件进行动态可靠性建模.在此基础上,运用随机摄动理论和四阶矩技术给出了动态可靠性灵敏度的求解公式,解决了参数服从任意分布的灵敏度求解问题.以零件螺栓为例建立了可靠性动态模型,给出了各参数变量的灵敏度随时间变化的动态曲线,并用Monte Carlo方法进行了验证,结果表明所建立的模型能准确反映出机械零件的可靠性随使用时间的变化规律.关键词:机械零件;随机载荷;Gamma过程......
监测数据,然后采用瑞士的GAMMA软件处理矿区的主辅两景InSAR影像,通过相位解缠等操作最终得到矿区地表的沉降图.以淮北某矿区一个工作面的地面观测数据为例,通过仿射变换进行坐标转换把地面上GPS观测点转换到对应的InSAR栅格数据阵列中,对比分析二者的观测数据,可以发现InSAR监测结果与GPS观测结果具有一致性,能够满足矿区地表沉降监测的精度要求.关键词:InSAR测量技术;地表沉降;GPS;仿射变换;GAMMA软件;......
