为更好地利用单词词性包含的语义信息和伴随单词出现时的非自然语言上下文信息,提出动态调整语义的词性加权多模态情感分析(part of speech weighted multi-modal sentiment analysis model with dynamic semantics adjustment,PW-DS)模...为更好地利用单词词性包含的语义信息和伴随单词出现时的非自然语言上下文信息,提出动态调整语义的词性加权多模态情感分析(part of speech weighted multi-modal sentiment analysis model with dynamic semantics adjustment,PW-DS)模型.该模型以自然语言为主体,分别使用基于Transformer的双向编码器表示(bidirectional encoder representation from Transformers,BERT)模型、广义自回归预训练(generalized autoregressive pretraining for language understanding,XLNet)模型和一种鲁棒优化的BERT预训练(robustly optimized BERT pretraining approach,RoBERTa)模型为文本模态做词嵌入编码;创建动态调整语义模块将自然语言和非自然语言信息有效结合;设计词性加权模块,提取单词词性并赋权以优化情感判别.与张量融合网络和低秩多模态融合等当前先进模型的对比实验结果表明,PW-DS模型在公共数据集CMU-MOSI和CMU-MOSEI上的平均绝对误差分别达到了0.607和0.510,二分类准确率分别为89.02%和86.93%,优于对比模型.通过消融实验分析了不同模块对模型效果的影响,验证了模型的有效性.展开更多
以四驱汽车轴间分动器箱体为研究对象,获得分动器箱体的噪声、振动与声振粗糙度(Noise、Vibration、Harshness,NVH)特性。建立分动器箱体有限元模型,将分动器箱体有限元仿真模态与试验模态结果进行对比分析;基于Adams构建分动器齿轮传...以四驱汽车轴间分动器箱体为研究对象,获得分动器箱体的噪声、振动与声振粗糙度(Noise、Vibration、Harshness,NVH)特性。建立分动器箱体有限元模型,将分动器箱体有限元仿真模态与试验模态结果进行对比分析;基于Adams构建分动器齿轮传动系统动力学模型,提取分动器工作时轴承处的加速度响应作为激励信号,获得分动器箱体的强迫振动响应特性;采用模态声传递向量(modal accoustic transfer vector,MATV)计算得到分动器箱体结构辐射声场,得到对辐射噪声峰值频率影响较大的模态,对分动器箱体铺设阻尼层。优化前后结果对比显示:对分动器箱体优化后,有效降低了分动器箱体峰值频率处的声压幅值,取得了较好的降噪效果。展开更多
Research on practical and verifiable prediction methods for the service life of bearings plays a critical role in improving the reliability and safety of aircraft engines. The concept of grade-life （GL） is introduce...Research on practical and verifiable prediction methods for the service life of bearings plays a critical role in improving the reliability and safety of aircraft engines. The concept of grade-life （GL） is introduced to de- scribe the service life of bearings. A GL prognostic model for aircraft engine bearings is proposed based on sup- port vector machine （SVM） and fuzzy logic inference. Firstly, the mathematical model is discussed to predict the physics-based GL （PGL）. Then, the diagnostic estimation model based on SVM is presented in detail to predict the empirical GL （EPL）. Thirdly, a fuzzy logic inference is adopted to fuse two GL predicted results. Finally, the GL prognostic model is verified by the run-to-failure data acquired from an accelerated life test of an aircraft bearing. The results show that the model provides a more practical and reliable prediction for the service life of bearings.展开更多
针对发动机辐射噪声问题展开研究,应用有限元法对某发动机进行模态计算,然后基于模态声传递向量(Model acoustic transfer vector,MATV)技术与边界元法,计算得到发动机的辐射噪声响应,并计算得到其噪声传递函数。基于此,对发动机机体辐...针对发动机辐射噪声问题展开研究,应用有限元法对某发动机进行模态计算,然后基于模态声传递向量(Model acoustic transfer vector,MATV)技术与边界元法,计算得到发动机的辐射噪声响应,并计算得到其噪声传递函数。基于此,对发动机机体辐射噪声进行传递路径分析。本文将有限元方法中的噪声响应计算应用到了发动机的噪声预估中,对发动机的振动噪声控制具有一定的学术价值以及工程意义。展开更多
文摘为更好地利用单词词性包含的语义信息和伴随单词出现时的非自然语言上下文信息,提出动态调整语义的词性加权多模态情感分析(part of speech weighted multi-modal sentiment analysis model with dynamic semantics adjustment,PW-DS)模型.该模型以自然语言为主体,分别使用基于Transformer的双向编码器表示(bidirectional encoder representation from Transformers,BERT)模型、广义自回归预训练(generalized autoregressive pretraining for language understanding,XLNet)模型和一种鲁棒优化的BERT预训练(robustly optimized BERT pretraining approach,RoBERTa)模型为文本模态做词嵌入编码;创建动态调整语义模块将自然语言和非自然语言信息有效结合;设计词性加权模块,提取单词词性并赋权以优化情感判别.与张量融合网络和低秩多模态融合等当前先进模型的对比实验结果表明,PW-DS模型在公共数据集CMU-MOSI和CMU-MOSEI上的平均绝对误差分别达到了0.607和0.510,二分类准确率分别为89.02%和86.93%,优于对比模型.通过消融实验分析了不同模块对模型效果的影响,验证了模型的有效性.
文摘以四驱汽车轴间分动器箱体为研究对象,获得分动器箱体的噪声、振动与声振粗糙度(Noise、Vibration、Harshness,NVH)特性。建立分动器箱体有限元模型,将分动器箱体有限元仿真模态与试验模态结果进行对比分析;基于Adams构建分动器齿轮传动系统动力学模型,提取分动器工作时轴承处的加速度响应作为激励信号,获得分动器箱体的强迫振动响应特性;采用模态声传递向量(modal accoustic transfer vector,MATV)计算得到分动器箱体结构辐射声场,得到对辐射噪声峰值频率影响较大的模态,对分动器箱体铺设阻尼层。优化前后结果对比显示:对分动器箱体优化后,有效降低了分动器箱体峰值频率处的声压幅值,取得了较好的降噪效果。
基金Supported by the China Postdoctoral Science Foundation(20100481500)~~
文摘Research on practical and verifiable prediction methods for the service life of bearings plays a critical role in improving the reliability and safety of aircraft engines. The concept of grade-life （GL） is introduced to de- scribe the service life of bearings. A GL prognostic model for aircraft engine bearings is proposed based on sup- port vector machine （SVM） and fuzzy logic inference. Firstly, the mathematical model is discussed to predict the physics-based GL （PGL）. Then, the diagnostic estimation model based on SVM is presented in detail to predict the empirical GL （EPL）. Thirdly, a fuzzy logic inference is adopted to fuse two GL predicted results. Finally, the GL prognostic model is verified by the run-to-failure data acquired from an accelerated life test of an aircraft bearing. The results show that the model provides a more practical and reliable prediction for the service life of bearings.
文摘针对发动机辐射噪声问题展开研究,应用有限元法对某发动机进行模态计算,然后基于模态声传递向量(Model acoustic transfer vector,MATV)技术与边界元法,计算得到发动机的辐射噪声响应,并计算得到其噪声传递函数。基于此,对发动机机体辐射噪声进行传递路径分析。本文将有限元方法中的噪声响应计算应用到了发动机的噪声预估中,对发动机的振动噪声控制具有一定的学术价值以及工程意义。
