A New Hidden Markov Model for Protein Quality Assessment Using Compatibility Between Protein Sequence and Structure

Protein structure Quality Assessment（QA） is an essential component in protein structure prediction and analysis. The relationship between protein sequence and structure often serves as a basis for protein structure QA.In this work, we developed a new Hidden Markov Model（HMM） to assess the compatibility of protein sequence and structure for capturing their complex relationship. More specifically, the emission of the HMM consists of protein local structures in angular space, secondary structures, and sequence profiles. This model has two capabilities：（1） encoding local structure of each position by jointly considering sequence and structure information, and（2）assigning a global score to estimate the overall quality of a predicted structure, as well as local scores to assess the quality of specific regions of a structure, which provides useful guidance for targeted structure refinement. We compared the HMM model to state-of-art single structure quality assessment methods OPUSCA, DFIRE, GOAP,and RW in protein structure selection. Computational results showed our new score HMM.Z can achieve better overall selection performance on the benchmark datasets.     

改进的HMM系统在英语语音合成中的研究

根据英语语言所具有的一些特性对HMM模型进行改进,设计出适合英语语音合成的上下文属性集以及用于模型聚类的问题集,提高了其建模和训练效果。此外,借助HTK和Festival等工具,以基频和声道谱参数为训练参数,最终实现此英语语音合成系统。从所合成语句的效果来看,合成语音整体稳定流畅,而且节奏感比较强。