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The purpose of this paper is to improve the hydraulic efficiency without changing the overall dimension. The blade profile optimization design of the aero-centrifugal pump based on the biharmonic equation surrogate model has been studied.

First of all, Bezier curves and linear function are used to control the annular angle distribution and the stacking angle of blade profile under the MATLAB platform. Grid independence analysis has been studied to find the finest mesh scheme. After the precision comparison of test data and computation fluid dynamics 15 sets of design parameters are carried out as the boundary condition of the biharmonic equation. The efficiency surrogate model of the biharmonic equation is constructed via iteratively solving of a discrete difference equation. The other two surrogate models of response surface model (RSM) and radial basis function neural network surrogate model (RBFNNSM) are compared with the biharmonic equation surrogate model by the standard of modified complex correlation coefficient R² and root mean square deviation (RSME). Finally, the artificial fish swarm algorithm has been used to find the global optimal design parameters with the objective function of highest efficiency.

The results show that the design parameters code conversion method can reduce the number of optimization parameters from five to three, makes the design space become a cube, and compared with RSM and RBFNNSM, the biharmonic equation surrogate model has higher precision with R² is 0.8958, RSME is 0.1382. The final optimum result of AFSA is at the point of [1 −1 −1]. The internal flow field analysis shows that after optimization the outlet relative velocity becomes more uniform and the wake effect has been significantly decreased. The hydraulic efficiency of the optimized pump is about 59.45 per cent increasing 5.4 per cent compared with a prototype pump.

This study developed a new method to optimize the design parameters of aero-centrifugal pump impeller based on biharmonic equation surrogate model, which had a good agreement with experimental values within just 15 sets of the original design. The optimization results shows that the method can improve the hydraulic efficiency significantly.

Corrosion thinning reduces the effective cross-sectional areas of steel structures and degrades their mechanical properties. This study aims to investigate the relationship between the corrosion thinning of carbon steel for transmission towers and the degradation of its mechanical properties.

A macroscopic finite element model of a transmission tower was established and then combined with the corrosion thinning and mechanical properties of Q355 steel in different test periods measured in neutral salt spray, SO₂ atmosphere and wet heat environments to conduct a finite element simulation of a transmission tower with different corrosion thinning of Q355 steel.

When the residual thickness of the tower leg angle was reduced to 4.03 mm, the maximum stress solved in the simulation exceeded the yield strength, with the tower already at risk of collapse owing to corrosion failure under extreme conditions of basic wind speed.

This study innovatively utilises transmission tower finite element models and experimental data from mechanical degradation experiments to quantify the relationship between corrosion thinning and the mechanical properties of Q355 steel, ensuring the effective assessment of the mechanical properties of corroded transmission towers.

The application of digital twins to optimise operations and supply chain management functions is a bourgeoning practice. Scholars have attempted to keep pace with this development initiating a fast-evolving research agenda. The purpose of this paper is to take stock of the emerging research stream identifying trends and capture the value potential of digital twins to the field of operations and supply chain management.

In this work we employ a bibliometric literature review supported by bibliographic coupling and keyword co-occurrence network analysis to examine current trends in the research field regarding the value-added potential of digital twin in operations and supply chain management.

The main findings of this work are the identification of four value clusters and one enabler cluster. Value clusters are comprised of articles that describe how the application of digital twin can enhance supply chain activities at the level of business processes as well as the level of supply chain capabilities. Value clusters of production flow management and product development operate at the business processes level and are maturing communities. The supply chain resilience and risk management value cluster operates at the capability level, it is just emerging, and is positioned at the periphery of the main network.

This is the first study that attempts to conceptualise digital twin as a dynamic capability and employs bibliometric and network analysis on the research stream of digital twin in operations and supply chain management to capture evolutionary trends, literature communities and value-creation dynamics in a digital-twin-enabled supply chain.

Using Shanghai as an example, the purpose of this paper is to perform grade evaluation and zoning for different land use spaces by GIS by identifying the major restrictive factors in current socio-economic development.

Based on short plate theory, 11 major restrictive indicators that will restrict socio-economic development in Shanghai are identified, and urban land is divided into four subspaces and the restrictive grade evaluation of urban land subspace is achieved with GIS spatial analysis; then, land development zoning is processed according to the results of the evaluation.

In all, 11 major restrictive indicators that will restrict socio-economic development in Shanghai are identified. The restrictive grades of the agricultural production, urban construction and ecological protection subspaces are mainly common, weak and weaker, and the relatively strong restrictive grade of industrial development subspace is mainly concentrated in the more developed industrial districts (counties). The areas of the common and good regions of constructive development and ecological development zones account for 87.4 and 98.3 per cent of each total area, respectively, and urban land still has significant development potential in Shanghai.

This paper proposes various urban land space evaluations and zoning strategies based on restrictive indicators and perspectives, enriching the ideas and methods of urban land use evaluation.