The pilot contamination caused by sharing the non-orthogonal pilots among users is considered to be a bottleneck of the massive multi-input multi-output (MIMO) systems. This paper proposes a pilot scheduling scheme based on the degradation to address this problem. Through computing the degradation of the users, the proposed scheduling assigns the optimal pilot sequence to the user who suffers from the greatest degradation in a greedy way. Moreover, the proposed scheme is further optimized with an extra set of orthogonal pilot sequences, which is called pilot scheduling scheme based on user grouping. Simulation results show that the target cell's achievable sum rate of the proposed scheme is much higher than the random pilot scheduling (RPS) and the smart pilot assignment (SPA) schemes; also, our scheme can reduce the impact of shadowing fading on the target cell's achievable sum rate effectively.

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Precise navigation and localization of the autonomous rover in unknown environment is important both for its own safety as well as for its ability to accomplish engineering and scientific objectives. In order to navigation autonomously the rover should have the ability of apperceiving the environment and avoiding the obstacles. Laser range finder is used to rebuild the environment and fuzzy reasoning method is used to avoid obstacles. Most importantly the rover process the sensor data to produce an estimate of its position while concurrently building a map of the environment. The improved filter algorithm is proposed to make the method feasible.

Ancestor worship is regarded as the key element of the Han people's belief system across most of China. However, the rituals pertaining to death, such as in funerals and annual ancestor worship, vary from place to place. For decades, the state has made tremendous efforts to reform and standardise funerals consistent with its path to modernization by insisting on more socialist practices rather than those that are perceived as ‘superstitious’ and ‘irrational’, such as burning paper and incense or performing rituals. I argue that despite regulating the use of funeral materials or memorial types, the state has failed to reform the essence of death rituals, that is, the duty of filial piety and people's conception of the afterlife. In addition, funerals and other rituals related to death contribute to individual's social reputation.