选择在600m^30km16个尺度上,在ArcGIS中利用常用的面积最大值法(Rule of Maximum Area,RMA)对2005年四川省1:25万土地覆被矢量数据进行栅格化,并采用两种属性精度损失评估方法:传统的常规分析方法和一种新的基于栅格单元分析方法,来对...选择在600m^30km16个尺度上,在ArcGIS中利用常用的面积最大值法(Rule of Maximum Area,RMA)对2005年四川省1:25万土地覆被矢量数据进行栅格化,并采用两种属性精度损失评估方法:传统的常规分析方法和一种新的基于栅格单元分析方法,来对比分析在这两种评估方法下RMA栅格化的属性(这里是指面积)精度损失随尺度的变化特征。结果表明:(1)在同一尺度下采用基于栅格单元方法分析所得的研究区平均属性精度损失大于常规分析方法分析得到的平均属性精度损失,且二者之间的差异在1~10km内很明显,当栅格单元大于10km时,两种方法得到的平均属性精度损失的差值稳定,且其随尺度的变化曲线趋于平行;(2)基于栅格单元分析方法不仅能够准确地定量估计RMA栅格化的属性精度损失,而且能客观地反映属性精度损失的空间分布规律;(3)对四川省1:25万土地覆被数据进行面积最大值法(RMA)栅格化的适宜尺度域最好不要超过800m,在该尺度域内数据工作量适宜,且RMA栅格化属性精度损失小于2.5%。展开更多
The effect of sucrose on nanometer Se0 in liquid phase was reported.Transmission electron microscope（TEM）,laser light scattering image and Resonance Rayleigh Scattering（RRS） were used to study the configuration an...The effect of sucrose on nanometer Se0 in liquid phase was reported.Transmission electron microscope（TEM）,laser light scattering image and Resonance Rayleigh Scattering（RRS） were used to study the configuration and stability of nanometer Se0 particles.The results show that sucrose solution modulated the assemble of nanometer Se0 particles and stabilized the Se0 particles in liquid phase.From the concentration of 1.07 to 42.8 μmol/L,the diameter of Se0 particles were 47—600 nm.However,in the presence of 1.0% sucrose solution,the major distribution range of Se0 diameter was 20—80 nm.Furthermore,the nanometer Se0 sol-gel could be preserved stably in sucrose solution at least for 2 months at 2—10 ℃.展开更多
文摘选择在600m^30km16个尺度上,在ArcGIS中利用常用的面积最大值法(Rule of Maximum Area,RMA)对2005年四川省1:25万土地覆被矢量数据进行栅格化,并采用两种属性精度损失评估方法:传统的常规分析方法和一种新的基于栅格单元分析方法,来对比分析在这两种评估方法下RMA栅格化的属性(这里是指面积)精度损失随尺度的变化特征。结果表明:(1)在同一尺度下采用基于栅格单元方法分析所得的研究区平均属性精度损失大于常规分析方法分析得到的平均属性精度损失,且二者之间的差异在1~10km内很明显,当栅格单元大于10km时,两种方法得到的平均属性精度损失的差值稳定,且其随尺度的变化曲线趋于平行;(2)基于栅格单元分析方法不仅能够准确地定量估计RMA栅格化的属性精度损失,而且能客观地反映属性精度损失的空间分布规律;(3)对四川省1:25万土地覆被数据进行面积最大值法(RMA)栅格化的适宜尺度域最好不要超过800m,在该尺度域内数据工作量适宜,且RMA栅格化属性精度损失小于2.5%。
文摘The effect of sucrose on nanometer Se0 in liquid phase was reported.Transmission electron microscope（TEM）,laser light scattering image and Resonance Rayleigh Scattering（RRS） were used to study the configuration and stability of nanometer Se0 particles.The results show that sucrose solution modulated the assemble of nanometer Se0 particles and stabilized the Se0 particles in liquid phase.From the concentration of 1.07 to 42.8 μmol/L,the diameter of Se0 particles were 47—600 nm.However,in the presence of 1.0% sucrose solution,the major distribution range of Se0 diameter was 20—80 nm.Furthermore,the nanometer Se0 sol-gel could be preserved stably in sucrose solution at least for 2 months at 2—10 ℃.
