Fast detection of soil nitrate has an important significance for variable rate fertilization.As NO-3ion selective electrode is easily affected by chloride ion and temperature interference in its practical application ...Fast detection of soil nitrate has an important significance for variable rate fertilization.As NO-3ion selective electrode is easily affected by chloride ion and temperature interference in its practical application for soil nutrient test,a three-layer artificial neural network model optimized by response surface methodology(RSM)was designed to reduce the interference of Cl-on NO-3ion selectivity electrode(ISE)in soil nitrate detection.The output of the model was NO-3-N concentration and three input parameters were temperature,response potential of ISE-NO-3and of ISE-Cl-.A multi-layer feed-forward(MLFF)network with one hidden layer and using gradient descent with momentum(GDM)as learning algorithm was used to develop the error correct model.By response surface methodology,a multivariate quadratic equation was developed to quantitatively describe the relationship between mean absolute error(MAE)and topological parameters of the artificial neuron network(ANN)model,then the optimum number of hidden neurons,momentum coefficient,training epoch,step size,and training runs were found.In range of 10 to 40℃,the best ANN model can correct interference of Cl-within 250 mg/kg while the primary ion concentration ranging from 5 to 250 mg/kg.For practical soil nutrient detection,the MAE could reach 8.6 mg/kg and relative standard deviation was lower than 6.5%compared with16%of no model correction.展开更多
Since linguistics is defined as the scientific study of language, it is obvious that such a study would help a lot in language teaching and learning. Linguistics defines the nature of language learning in connection w...Since linguistics is defined as the scientific study of language, it is obvious that such a study would help a lot in language teaching and learning. Linguistics defines the nature of language learning in connection with various linguistic theories therefore it helps the teachers to choose teaching methods and techniques. Furthermore, the process of linguistic study can be summarized as follows: First, certain linguistic facts are observed, which are found to display some similarities and generalizations, hypotheses are formulated to account for these facts; and then make sure these hypotheses; finally a rule of linguistics is constructed. Our students are doing the same. They imitated what the teacher did and did what the teacher told them to. At last, they bear the usage of English in minds.展开更多
Researchers in the field of Second Language Acquisition (SLA) have long held the interest towards the teaching of college English writing. Their research topics, range from how to improve college students'ability ...Researchers in the field of Second Language Acquisition (SLA) have long held the interest towards the teaching of college English writing. Their research topics, range from how to improve college students'ability to write with English as their second language, to how to correct their wrong expressions in their writing. This article mainly aims at exploring college students' various writing errors and mistakes,trying to provide some hints for college students and teachers about English writing. Such studies are abundant.展开更多
文摘Fast detection of soil nitrate has an important significance for variable rate fertilization.As NO-3ion selective electrode is easily affected by chloride ion and temperature interference in its practical application for soil nutrient test,a three-layer artificial neural network model optimized by response surface methodology(RSM)was designed to reduce the interference of Cl-on NO-3ion selectivity electrode(ISE)in soil nitrate detection.The output of the model was NO-3-N concentration and three input parameters were temperature,response potential of ISE-NO-3and of ISE-Cl-.A multi-layer feed-forward(MLFF)network with one hidden layer and using gradient descent with momentum(GDM)as learning algorithm was used to develop the error correct model.By response surface methodology,a multivariate quadratic equation was developed to quantitatively describe the relationship between mean absolute error(MAE)and topological parameters of the artificial neuron network(ANN)model,then the optimum number of hidden neurons,momentum coefficient,training epoch,step size,and training runs were found.In range of 10 to 40℃,the best ANN model can correct interference of Cl-within 250 mg/kg while the primary ion concentration ranging from 5 to 250 mg/kg.For practical soil nutrient detection,the MAE could reach 8.6 mg/kg and relative standard deviation was lower than 6.5%compared with16%of no model correction.
文摘Since linguistics is defined as the scientific study of language, it is obvious that such a study would help a lot in language teaching and learning. Linguistics defines the nature of language learning in connection with various linguistic theories therefore it helps the teachers to choose teaching methods and techniques. Furthermore, the process of linguistic study can be summarized as follows: First, certain linguistic facts are observed, which are found to display some similarities and generalizations, hypotheses are formulated to account for these facts; and then make sure these hypotheses; finally a rule of linguistics is constructed. Our students are doing the same. They imitated what the teacher did and did what the teacher told them to. At last, they bear the usage of English in minds.
文摘Researchers in the field of Second Language Acquisition (SLA) have long held the interest towards the teaching of college English writing. Their research topics, range from how to improve college students'ability to write with English as their second language, to how to correct their wrong expressions in their writing. This article mainly aims at exploring college students' various writing errors and mistakes,trying to provide some hints for college students and teachers about English writing. Such studies are abundant.
