随着网络技术的发展,即时通信已成为现在人们日常生活中广泛使用的通信技术。XMPP(Extensible Messaging and Presence Protocol)可扩展消息与出席协议[1],因其良好的可扩展性与充分的开放性,成为了即时通信应用使用的主流协议之一。但...随着网络技术的发展,即时通信已成为现在人们日常生活中广泛使用的通信技术。XMPP(Extensible Messaging and Presence Protocol)可扩展消息与出席协议[1],因其良好的可扩展性与充分的开放性,成为了即时通信应用使用的主流协议之一。但它的核心协议集只是达到了即时通信所需的最低标准,因此还存在一定的缺陷和问题,例如消息确认机制效率低下、文件传输效率低下以及移动网络下网络连接稳定性的问题。所以,利用XMPP协议良好的可扩展性和开放性,可以对它进行针对性的优化。文章通过分析XMPP协议在实际应用中展现出来的缺陷和问题,设计了对应的优化方案。展开更多
In order to overcome the disadvantages of diagonal connection structures that are complex and for which it is difficult to derive the discriminant of the airflow directions of airways, we have applied a multiple regre...In order to overcome the disadvantages of diagonal connection structures that are complex and for which it is difficult to derive the discriminant of the airflow directions of airways, we have applied a multiple regression method to analyze the effect, of changing the rules of mine airflows, on the stability of a mine ventilation system. The amount of air （ Qj ） is determined for the major airway and an optimum regression equation was derived for Qi as a function of the independent variable （ Ri ）, i.e., the venti- lation resistance between different airways. Therefore, corresponding countermeasures are proposed according to the changes in airflows. The calculated results agree very well with our practical situation, indicating that multiple regression analysis is simple, quick and practical and is therefore an effective method to analyze the stability of mine ventilation systems.展开更多
文摘随着网络技术的发展,即时通信已成为现在人们日常生活中广泛使用的通信技术。XMPP(Extensible Messaging and Presence Protocol)可扩展消息与出席协议[1],因其良好的可扩展性与充分的开放性,成为了即时通信应用使用的主流协议之一。但它的核心协议集只是达到了即时通信所需的最低标准,因此还存在一定的缺陷和问题,例如消息确认机制效率低下、文件传输效率低下以及移动网络下网络连接稳定性的问题。所以,利用XMPP协议良好的可扩展性和开放性,可以对它进行针对性的优化。文章通过分析XMPP协议在实际应用中展现出来的缺陷和问题,设计了对应的优化方案。
基金Project F010206 supported by the National Natural Science Foundation of China
文摘In order to overcome the disadvantages of diagonal connection structures that are complex and for which it is difficult to derive the discriminant of the airflow directions of airways, we have applied a multiple regression method to analyze the effect, of changing the rules of mine airflows, on the stability of a mine ventilation system. The amount of air （ Qj ） is determined for the major airway and an optimum regression equation was derived for Qi as a function of the independent variable （ Ri ）, i.e., the venti- lation resistance between different airways. Therefore, corresponding countermeasures are proposed according to the changes in airflows. The calculated results agree very well with our practical situation, indicating that multiple regression analysis is simple, quick and practical and is therefore an effective method to analyze the stability of mine ventilation systems.
