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In the digital economy era, cloud–edge collaboration technology provides the necessary technical support for the digital transformation of enterprises, which can improve the quality of services (QoS), and it attracts extensive attention from scholars and entrepreneurs from all fields. Under the bounded-rationality hypothesis, this paper investigates the service mechanism for the cloud–edge collaboration system considering the quality of experience (QoE) and presents a dynamic evolutionary game model between cloud service providers and edge operators by applying the evolutionary game theory. Then, this paper analyzes the equilibrium and stability conditions for the decision-making of both parties involved to guarantee the QoE reaches the ideal state. In addition, we investigate the factors that influence the stable cooperation between the two evolutionary stable strategies and validate the theoretical analytical results with numerical simulations. The research results show that the final evolution of the cloud–edge collaboration system depends on the benefits and costs of the game matrix between the two parties and the initial state values of the system. Under a specific condition, the cloud–edge collaboration system can eventually be driven to be an ideal state by reducing the collaboration cost and improving the collaboration benefit. The more both parties focus on the QoE, the more conducive it will be for the formation of a cloud–edge collaboration, thus effectively promoting long-term stability and better serving enterprises’ digital transformation.

In this paper, we propose a novel integrated communication and positioning design for orthogonal frequency division multiplexing system aided by a reconfigurable intelligent surface (RIS) in indoor circumstances. The channel frequency responses on pilots (CFROPs) of places of interest are used for online mapping with the offline CFROP database. We transform the objective of minimizing the similarity of different CFROPs into creating a differentiated database by optimizing the phase coefficients of RIS. Imperfect channel state information is considered due to time-varying caused by the two-stage mapping. We formulate a universal optimization problem for maximizing either the average or the minimum virtual distance of CFROPs. The communication service requirements are converted as constraints. A moderate case is discussed to reduce computational complexity with minor accuracy loss. A special property called correlation dispersion is analyzed. It is capable of eliminating the spatial consistency that incurs inaccuracy to traditional positioning methods. The property and the moderate case complement each other well with clear and logical physical interpretation. The particular characteristic makes our design outperform others especially in high-level-noise environments. It works even better when the prior information of user's potential location is available. The validity of our design is confirmed by numerical results., Comment: 31 pages

There is 18,000 km of coastline in China. It is extremely important to construct coastal shelterbelts as they have a unique and irreplaceable role in the prevention and mitigation of natural disasters and in maintaining the ecological balance of coastal regions. A coastal shelterbelt was constructed near Yuyao City, Zhejiang Province, and three plots (wasteland, farmland, and forest) were studied to investigate the effects of environmental factors on the diversity of herbaceous plants. The environmental benefits were analyzed by field surveys and soil sampling. A total of 31 species from 30 genera and 14 families of halophyte and salt‐tolerant grasses were found in the survey area. The wasteland included 21 species from 20 genera and 9 families, whereas the shelterbelt forest had 19 species from 19 genera and 8 families, with Poaceae and Asteraceae dominating. Moreover, the Sorensen coefficient for the shelterbelt forest and wasteland was 65 and that for the shelterbelt forest and farmland was 55.56. Additionally, the salinity decreased from 0.52% to 0.02% after 2 years, similar to the value for farmland that has been cultivated for decades. The organic matter content increased from 5.1 to 9.5 g/kg, and the total nitrogen content increased from 0.34 to 0.47 g/kg. We concluded that coastline shelterbelts could be successfully established on the muddy coast. With coastline shelterbelts growing, the structure and diversity of herbaceous plants were affected, and the soil conditions were improved. Therefore, the construction of shelterbelt forest would improve the coastal landscape and enhance soil properties, accelerating the succession of herbaceous plants.