在大豆油脂过氧化值近红外光谱分析中,利用间隔偏最小二乘法(interval partial least square,iPLS)实现油脂光谱特征波段选择。分别将全谱波段以10个数据点间隔和20个数据点间隔分成若干个小波段,然后对全谱和每个小波段分别用PLS回归建...在大豆油脂过氧化值近红外光谱分析中,利用间隔偏最小二乘法(interval partial least square,iPLS)实现油脂光谱特征波段选择。分别将全谱波段以10个数据点间隔和20个数据点间隔分成若干个小波段,然后对全谱和每个小波段分别用PLS回归建模,用预测残差平方和(predicted residual sum of squares,PRESS)对模型进行评价。结果表明:经过特征波段选择后,50个波长点模型的决定系数、预测误差均方根、相对误差均值分别为0.9791、0.0513和2.12%,有效地减少建模的变量数,预测精度得到提高。展开更多
The purpose of this study was to clarify the relationships between results of index tests and uniaxial compressive strength (UCS) in hydrothermally altered soft rocks of the Upper Miocene, which are typical of the sof...The purpose of this study was to clarify the relationships between results of index tests and uniaxial compressive strength (UCS) in hydrothermally altered soft rocks of the Upper Miocene, which are typical of the soft rock found in northeastern Hokkaido, Japan. Index tests were performed using point load testing machine and needle penetrometer with irregular lump specimens under forced-dry, forced-wet, and natural-moist states. The relationships between irregular lump point load strength (IPLS) index and UCS, and needle penetration (NP) index and UCS were “UCS = approximately 19 IPLS index” and “UCS = 0.848 (NP index)0.619”, respectively, in soft rocks with a UCS below 25 MPa. These relationships could be applied to on-site tests of rocks with natural moisture content. The UCS could be calculated from IPLS and NP tests on soft rocks only when UCS was below 25 MPa, using the equations obtained as a result of this study.展开更多
文摘在大豆油脂过氧化值近红外光谱分析中,利用间隔偏最小二乘法(interval partial least square,iPLS)实现油脂光谱特征波段选择。分别将全谱波段以10个数据点间隔和20个数据点间隔分成若干个小波段,然后对全谱和每个小波段分别用PLS回归建模,用预测残差平方和(predicted residual sum of squares,PRESS)对模型进行评价。结果表明:经过特征波段选择后,50个波长点模型的决定系数、预测误差均方根、相对误差均值分别为0.9791、0.0513和2.12%,有效地减少建模的变量数,预测精度得到提高。
文摘The purpose of this study was to clarify the relationships between results of index tests and uniaxial compressive strength (UCS) in hydrothermally altered soft rocks of the Upper Miocene, which are typical of the soft rock found in northeastern Hokkaido, Japan. Index tests were performed using point load testing machine and needle penetrometer with irregular lump specimens under forced-dry, forced-wet, and natural-moist states. The relationships between irregular lump point load strength (IPLS) index and UCS, and needle penetration (NP) index and UCS were “UCS = approximately 19 IPLS index” and “UCS = 0.848 (NP index)0.619”, respectively, in soft rocks with a UCS below 25 MPa. These relationships could be applied to on-site tests of rocks with natural moisture content. The UCS could be calculated from IPLS and NP tests on soft rocks only when UCS was below 25 MPa, using the equations obtained as a result of this study.
