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In order to solve the problem of large-scale backflow in side-inlet forebay of Shiqiao Pumping Station in Yangzhou City, Jiangsu Province, Shiqiao Pumping Station intake structure is taken as the research object based on Reynolds time-averaged equation and RNG k-ε model, CFD software is used for numerical calculation of side-inlet forebay and intake sump. The flow characteristics of forebay and intake sump are analyzed under different rectification measures. Several rectification measures are proposed and the effect of flow pattern control is quantitatively analyzed. The result shows that the flow pattern of 2# and 6# intake sump is comparatively disordered without rectification measures, as the streamline is distributed unevenly. Through an analysis of three rectification measures, the streamline distribution of the intake sump is uniform and the flow velocity distribution is reasonable when the bottom ridge is added to the forebay. Axial velocity distribution uniformity of inlet characteristic section in intake sump is increased by about 30% on average in each pump unit, indicating a significant rectification effect. The research findings serve as a reference for the flow pattern improvement of similar pumping station projects. [ABSTRACT FROM AUTHOR]

People make decisions based on their cognitive information about the objective world. Zadeh's Z-number allows people to better express their cognition of the real world by considering the fuzzy restriction and reliability restriction of information. However, the Z-number is a complex construct, and some important issues must be discussed in its study. Here, a computationally simple method of ranking Z-numbers for multi-criteria decision-making (MCDM) problems is proposed, and a comprehensive possibility degree of Z-numbers is defined, as inspired by the possibility degree concept of interval numbers. The outranking relations of Z-numbers are also discussed on the basis of the proposed method. Then, a weight acquisition algorithm relative to the possibility degree of Z-numbers is presented. Finally, an extended Preference Ranking Organization Method for Enrichment Evaluation II (PROMETHEE II) based on the possibility degree of Z-numbers is developed for the MCDM problem under Z-evaluation, and a numerical example about the selection of travel plans is used to illustrate the validity of the proposed method. The applicability and superiority of the proposed method is demonstrated through sensitivity and comparative analyses along with other existing methods. [ABSTRACT FROM AUTHOR]