针对现存交通事故文本信息中存在的大量时间、地点、伤亡损失等关键异构数据难以有效提取,以及用静态词向量深度学习模型提取交通事故文本信息精确度较低的问题,本文利用BERT(Bidirectional Encoder Representations from Transformers...针对现存交通事故文本信息中存在的大量时间、地点、伤亡损失等关键异构数据难以有效提取,以及用静态词向量深度学习模型提取交通事故文本信息精确度较低的问题,本文利用BERT(Bidirectional Encoder Representations from Transformers)对文本字符进行动态向量映射,从数据表达源头解决一词多义、上下文依赖不充分等问题;利用BiGRU(Bi-Gate Recurrent Unit)提取文本向量化后的特征,输出高特征的文本序列;利用CRF(Conditional Random Fields)计算全局最优输出节点的概率优势,优化文本序列特征结果,提出一种基于动态字向量的BERT-BiGRU-CRF融合模型,用于交通事故文本关键信息提取。通过对比实验表明,该模型在交通事故文本信息提取中平均准确率为0.952,F1为0.925,比基于静态词向量Word2Vec模型的精确率与F1值分别提高了6.3个百分点和7.9个百分点。展开更多
The acoustic focusing effect of metamaterial has a wide range of applications in medicine,acoustic imaging,signal detection,etc.This paper presents an acoustic metamaterial applied to the acoustic focusing effect.The ...The acoustic focusing effect of metamaterial has a wide range of applications in medicine,acoustic imaging,signal detection,etc.This paper presents an acoustic metamaterial applied to the acoustic focusing effect.The formation of acousticmetamaterial is designed into a cylindrical structure with three layers of ludox,cork and fluid rubber,which can produce a focusingphenomenon when acoustic waves propagate in air.For these strange phenomena,a scientific description is given theorietically.It can also be concluded that when the frequency of the incident acoustic wave increases?the number of peripheral bandsoutside the focusing poles will increase periodically.Besides,there are numerous groups of multipolar focusing phenomena inhigh frequency.The design of this acoustic metamaterial is successful through theorietical and experimental verification,therefore,it can be applied to acoustic communication and test.展开更多
Research of the acoustic local effect of metamaterial is widely used in the fields of environmental science,military industry and biomedicine.In this paper,the metamaterial is designed by annular columnar structures.T...Research of the acoustic local effect of metamaterial is widely used in the fields of environmental science,military industry and biomedicine.In this paper,the metamaterial is designed by annular columnar structures.The acoustic local effect in slender columnar structure with two layers of rings in air is investigated.Results prove that when the plane acoustic wave is incident into the model,complex interference and diffraction occur.And at different frequencies,multipolar acoustic local effect existes and cycle distribution phenomenon is observed.It is noteworthy that this phenomenon has very weak relatedness with the materials and acoustic parameters of the model.The research of this metamaterial design in this paper has definite reference significance in the acoustic communication and amplification of the acoustic signal detection.展开更多
文摘针对现存交通事故文本信息中存在的大量时间、地点、伤亡损失等关键异构数据难以有效提取,以及用静态词向量深度学习模型提取交通事故文本信息精确度较低的问题,本文利用BERT(Bidirectional Encoder Representations from Transformers)对文本字符进行动态向量映射,从数据表达源头解决一词多义、上下文依赖不充分等问题;利用BiGRU(Bi-Gate Recurrent Unit)提取文本向量化后的特征,输出高特征的文本序列;利用CRF(Conditional Random Fields)计算全局最优输出节点的概率优势,优化文本序列特征结果,提出一种基于动态字向量的BERT-BiGRU-CRF融合模型,用于交通事故文本关键信息提取。通过对比实验表明,该模型在交通事故文本信息提取中平均准确率为0.952,F1为0.925,比基于静态词向量Word2Vec模型的精确率与F1值分别提高了6.3个百分点和7.9个百分点。
基金National Natural Science Foundation of China(No.61671414)Natural Science Foundation for Young Scientists of Shanxi Province,China(No.201601D202035)
文摘The acoustic focusing effect of metamaterial has a wide range of applications in medicine,acoustic imaging,signal detection,etc.This paper presents an acoustic metamaterial applied to the acoustic focusing effect.The formation of acousticmetamaterial is designed into a cylindrical structure with three layers of ludox,cork and fluid rubber,which can produce a focusingphenomenon when acoustic waves propagate in air.For these strange phenomena,a scientific description is given theorietically.It can also be concluded that when the frequency of the incident acoustic wave increases?the number of peripheral bandsoutside the focusing poles will increase periodically.Besides,there are numerous groups of multipolar focusing phenomena inhigh frequency.The design of this acoustic metamaterial is successful through theorietical and experimental verification,therefore,it can be applied to acoustic communication and test.
基金National Natural Science Foundation of China(No.61671414)Natural Science Foundation for Young Scientists of Shanxi Province,China(No.201601D202035)
文摘Research of the acoustic local effect of metamaterial is widely used in the fields of environmental science,military industry and biomedicine.In this paper,the metamaterial is designed by annular columnar structures.The acoustic local effect in slender columnar structure with two layers of rings in air is investigated.Results prove that when the plane acoustic wave is incident into the model,complex interference and diffraction occur.And at different frequencies,multipolar acoustic local effect existes and cycle distribution phenomenon is observed.It is noteworthy that this phenomenon has very weak relatedness with the materials and acoustic parameters of the model.The research of this metamaterial design in this paper has definite reference significance in the acoustic communication and amplification of the acoustic signal detection.
