基于IIP的多媒体彩铃系统的设计与实现①

首先介绍了基于IMS（IP Multimedia Subsystem,IP多媒体子系统）实现多媒体彩铃（Multimedia Ring Back Tone,MRBT）业务的工作原理,在分析了该方案优缺点后,提出了一种快速、经济的基于独立智能外设（Independent Intelligent Peripheral,IIP）的由控制节点CN通过VIPS（Virtual Integrated Programmable Switch,虚拟综合可编程交换机）控制MSIP（MultiMedia Server Intellectual Processor,多媒体服务器智能处理板）板卡实现多媒体彩铃业务的方案,分析了此方案的系统结构、内部信令的交互流程,最后列出了具体的功能模块修改点。     

Thermal stability of γ-Al2O3 coatings for challenging cutting operations

Crystalline PVD Al₂O₃ coatings offer great potential for their use in cutting operations. They promise high hot hardness and high oxidation resistance at elevated temperatures. Alumina exists in different crystallographic phases. α-Al₂O₃ appears to be the only thermodynamically stable phase at all common temperatures and pressures. Today there are many efforts to generate α-Al₂O₃ by means of physical vapour deposition. In this regard one problem is the high deposition temperature, which does not allow the deposition on temperature-sensitive materials.Another promising candidate is γ-Al₂O₃ which is more fine-grained than α-Al₂O₃ and can be deposited at lower temperatures. At high temperatures γ-Al₂O₃ might be transformed into α-Al₂O₃, which could limit the application temperature. But until now it is not clearly proved, up to which temperatures γ-Al₂O₃ thin films are stable and which mechanisms influence the stability. In the present work different (Ti,Al)N/γ-Al₂O₃ coatings are deposited on cemented carbides by means of Magnetron Sputter Ion Plating (MSIP). The (Ti,Al)N bond coat was employed to improve adhesion of γ-Al₂O₃ on the substrate. It could be shown that the γ-phase is stable in vacuum up to 1200 °C. In the atmosphere the formation of α-Al₂O₃ begins at 900 °C and it is influenced by the choice of transition zone between the (Ti,Al)N interlayer and γ-Al₂O₃. The results show that the thermal stability of the γ-phase and therefore the application temperature of the coating can be enhanced by the choice of interlayer.