双耳时间差上升沿算法中阈值的选择

上升沿法是计算双耳时间差的1种常用方法。采用3种不同对象的头相关脉冲响应数据,分别计算了不同判定阈值(5%,10%,15%,20%)下的双耳时间差,研究了上升沿算法中合理的判定阈值范围以及采用不同判定阈值时上升沿算法的稳定性。结果表明,判定阈值的选择与研究对象、头相关脉冲响应获取手段等因素有关;而稳定性主要取决于双耳头相关脉冲响应的上升斜率,复杂的、非对称的生理结构将使声源异侧耳的上升斜率减小,从而导致上升沿算法的不稳定,这在侧向表现得最明显;建议采用10%的判定阈值。

Modeling personalized head-related impulse response using support vector regression

A new customization approach based on support vector regression （SVR） is proposed to obtain individual headrelated impulse response （HRIR） without complex measurement and special equipment. Principal component analysis （PCA） is first applied to obtain a few principal components and corresponding weight vectors correlated with individual anthropometric parameters. Then the weight vectors act as output of the nonlinear regression model. Some measured anthropometric parameters are selected as input of the model according to the correlation coefficients between the parameters and the weight vectors. After the regression model is learned from the training data, the individual HRIR can be predicted based on the measured anthropometric parameters. Compared with a back-propagation neural network （BPNN） for nonlinear regression, better generalization and prediction performance for small training samples can be obtained using the proposed PCA-SVR algorithm.

宁夏蓖麻蚕丝与中卫山羊毛混纺纱产品的工艺研究

本文主要研究宁夏蓖麻蚕丝与中卫山羊毛混纺纱产品的工艺技术问题。通过多个工艺试验方案，选出了合适的生产工艺方案，并成功地纺制出具有良好风格特性的混纺纱产品。

虚拟听觉空间中运动声源的模拟

文中提出一种在虚拟听觉空间中加入多普勒效应以提高模拟运动物体效果的方法。该方法通过对原始声源运动轨迹的分析，对声源信号进行多普勒调频，并根据耳间时间差对双耳信号进行调相。最后利用连续球面空间上的HRIR对双耳信号进行滤波处理。经过验证，该方法处理后的声源信号运动感觉强烈。它为实现虚拟听觉空间提供了一种有益的新方法。

头相关函数时域建模仿真研究

对头相关相关函数进行了双耳的时域主分量分析,提取方位特征。对主分量进行了详细的讨论,并给出了一种实时条件下适用的矩阵迭代算法。用2种不同的方案对HRIR进行数值逼近,实验结果表明了方法的有效性。

Individualization of Head Related Impulse Responses Using Division Analysis

For Virtual Reality(VR) to be truly immersive, it needs convincing sound to match. Due to the diversity of individual's anthropometric measurements, the individualized customization technology is needed to get convincing sound. In this paper, we proposed a simple and effective method for modeling relationships between anthropometric measurements and Head-related Impulse Response(HRIR). Considering the relationship between anthropometric measurements and different HRIR parts is complicated, we divided the HRIRs into small segments and carried out regression analysis between anthropometric measurements and each segment to establish relationship model. The results of objective simulation and subjective test indicate that the model can generate individualize HRIRs from a series of anthropometric measurements. With the individualized HRIRs, we can get more accurate acoustic localization sense than using non-individualized HRIRs.

三维声双耳渲染及其评价

本文分析了未来广播电视声音的特点和三维声的应用场景,回顾了三维声耳机渲染的实现原理和关键技术,对两种基于HRTF双耳渲染算法设计了主观评价方法并进行了评价。考虑到三维声双耳渲染带来的全新的声音特点,应用的主观评价方法不同于音频评价常用的无基准和有基准方法。