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Objectives: With the popularity of mobile devices and low‑cost sensors,the universal positioning capability of mobile terminals has become a strong demand. In order to build a universally available cloud positioning system, it is necessary to use various positioning sensors in smart terminals to obtain wireless signals, and search in the positioning database to complete the calculation of the position.Methods: In light of smart phone devices in location based service(LBS) scenarios, we focus on location service for massive smart phone devices and put forward the cloud computing network architecture. The breakthroughs on key engineering technologies such as hierarchical cloud positioning capabilities, low ‑cost access for developers, fault tolerance strategy and distributed positioning services are gained. Results: The testing result shows that cloud positioning system has realized the access processing capability of hundreds of billions of requests per day. Conclusions: Consequently, the system can provide location services for hundreds of millions of users and can be widely used in various location based applications. [ABSTRACT FROM AUTHOR]

Nowadays operators are focusing on developing the video communication services based on smart terminals.The characteristics and key affecting factors of video communication quality were discussed.Furthermore，according to the analysis of the methods of subjective and objective video quality assessment，an assessment model of video communication service quality was proposed and verified by experimental data，which can provide test reference and evaluation methods for operators to improve the quality of video communication service.