“近年来,基于深度学习的端到端自动语音识别模型直接对语音和文本进行建模,结构简单且性能上也具有显著优势,逐渐成为主流。然而,由于连续的语音信号与离散的文本在长度及表示尺度上存在巨大差异,二者间的模态鸿沟问题是该类任务一直存在的困扰。为解决该问题,本文提出了多尺度语音识别建模方法,该方法从利用细粒度分布知识的角度出发,建立多个不同尺度形式的文本信息,将特征序列从细粒度的低层次序列逐步对齐预测出文本序列。这种逐级预测的方式能够有效降低预测难度,缓解模态鸿沟带来的影响,并通过融合不同尺度下特征,提高语料信息的丰富性与完整性,进一步增强模型推理能力。本文在LibriSpeech小规模、大规模和TEDLIUM2数据集上实验,相比基线系统词错误率平均降低1.7、0.45和0.76,验证了方法的有效性。”

This paper describes the NiuTrans neural machine translation systems of the WMT22 General MT constrained task. We participate in four directions, including Chinese→English, English→Croatian, and Livonian↔English. Our models are based on several advanced Transformer variants, e.g., Transformer-ODE, Universal Multiscale Transformer (UMST). The main workflow consists of data filtering, large-scale data augmentation (i.e., iterative back-translation, iterative knowledge distillation), and specific-domain fine-tuning. Moreover, we try several multi-domain methods, such as a multi-domain model structure and a multi-domain data clustering method, to rise to this year’s newly proposed multi-domain test set challenge. For low-resource scenarios, we build a multi-language translation model to enhance the performance, and try to use the pre-trained language model (mBERT) to initialize the translation model.