基于入耳式耳机电阻抗特性的个性化均衡研究*

入耳式耳机封闭耳道会大幅改变耳道辐射阻抗,使得耳道内声压产生畸变进而导致头中定位效应。该文首次通过建模分析耳机与外耳耦合时声负载的变化,建立起耳机电阻抗与个性化耳机-耳道传递函数的关系。根据耳机电阻抗设计个性化滤波器以消除传递函数中高Q值的共振峰,均衡耳道内声压畸变。主观实验结果表明,基于耳机电阻抗特性的个性化均衡对于消除头中定位效应有显著作用。     

Self-implementation of ISO 9001 versus external support: an examination in laboratories involved in chemical measurement

The purpose of this research was to study how externalizing the process of implementing ISO 9001 influences the dissemination of cultural values and practices of quality management in laboratories involved in chemical measurement. Employee attitudes and behaviors may be heavily influenced by factors such as the mix of internal workers and consultants in a work group. Some researchers have described cases in which internal workers develop negative work attitudes and behaviors from having to work with consultants and have demonstrated the need to examine the dynamics between internal workers and consultants to understand the influence of ISO 9001 externalization. Three hundred and fifty-nine useful questionnaires were received. The results showed that implementation occurs most successfully through a process of linked internalization. This category involves limiting the labor of the consultant basically to moderate advising, review and internal audit. The laboratory personnel are responsible for developing the documentation of the ISO 9001 system. The implementation process is run by the members and directors of the laboratory.