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维汉接触中的竞争式有序匹配和异步回归——兼论汉语民族方言的形成与演变特点
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作者 杜兆金 《语言研究集刊》 2023年第2期157-177,392,共22页
文章基于田野调查材料,考察维吾尔语和汉语接触中维吾尔族人习得汉语声调的过程和机制。研究发现,维式汉语声调的发展会先后经历三个阶段:无序匹配—调类的有序匹配—声调调值回归。维吾尔族人在刚开始学习汉语声调时,会以母语中存在的... 文章基于田野调查材料,考察维吾尔语和汉语接触中维吾尔族人习得汉语声调的过程和机制。研究发现,维式汉语声调的发展会先后经历三个阶段:无序匹配—调类的有序匹配—声调调值回归。维吾尔族人在刚开始学习汉语声调时,会以母语中存在的“平调(33)”“升调(24)”“降调(51)”三种调型无规律匹配汉语某个声调,属于无序匹配。声调的无序匹配会逐步转化为有序匹配。无序匹配向有序匹配的转化是通过不同匹配方式之间的竞争实现的。维式汉语声调调值的回归具有异步性。维式汉语声调的形成和演变,体现出汉语民族方言的变异性、中介性及其发展演变的动态性。 展开更多
关键词 语言接触 汉语民族方言 无序匹配 竞争式有序匹配 异步回归
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Spatial Estimation of Saturated Hydraulic Conductivity from Terrain Attributes Using Regression,Kriging,and Artificial Neural Networks 被引量:7
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作者 H.R.MOTAGHIAN J.MOHAMMADI 《Pedosphere》 SCIE CAS CSCD 2011年第2期170-177,共8页
Several methods,including stepwise regression,ordinary kriging,cokriging,kriging with external drift,kriging with varying local means,regression-kriging,ordinary artificial neural networks,and kriging combined with ar... Several methods,including stepwise regression,ordinary kriging,cokriging,kriging with external drift,kriging with varying local means,regression-kriging,ordinary artificial neural networks,and kriging combined with artificial neural networks,were compared to predict spatial variation of saturated hydraulic conductivity from environmental covariates.All methods except ordinary kriging allow for inclusion of secondary variables.The secondary spatial information used was terrain attributes including elevation,slope gradient,slope aspect,profile curvature and contour curvature.A multiple jackknifing procedure was used as a validation method.Root mean square error (RMSE) and mean absolute error (MAE) were used as the validation indices,with the mean RMSE and mean MAE used to judge the prediction quality.Prediction performance by ordinary kriging was poor,indicating that prediction of saturated hydraulic conductivity can be improved by incorporating ancillary data such as terrain variables.Kriging combined with artificial neural networks performed best.These prediction models made better use of ancillary information in predicting saturated hydraulic conductivity compared with the competing models.The combination of geostatistical predictors with neural computing techniques offers more capability for incorporating ancillary information in predictive soil mapping.There is great potential for further research and development of hybrid methods for digital soil mapping. 展开更多
关键词 digital elevation model GEOSTATISTICS soil hydraulic properties spatial mapping
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