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Given the regional heterogeneity of economic development, electricity consumption in various regions exhibits a discrepant growth pattern. The purpose of this study is to construct a grey system forecasting model with intelligent parameters for predicting provincial electricity consumption in China.

First, parameter optimization and structural expansion are simultaneously integrated into a unified grey system prediction framework, enhancing its adaptive capabilities. Second, by setting the minimum simulation percentage error as the optimization goal, the authors apply the particle swarm optimization (PSO) algorithm to search for the optimal grey generation order and background value coefficient. Third, to assess the performance across diverse power consumption systems, the authors use two electricity consumption cases and select eight other benchmark models to analyze the simulation and prediction errors. Further, the authors conduct simulations and trend predictions using data from all 31 provinces in China, analyzing and predicting the development trends in electricity consumption for each province from 2021 to 2026.

The study identifies significant heterogeneity in the development trends of electricity consumption systems among diverse provinces in China. The grey prediction model, optimized with multiple intelligent parameters, demonstrates superior adaptability and dynamic adjustment capabilities compared to traditional fixed-parameter models. Outperforming benchmark models across various evaluation indicators such as root mean square error (RMSE), average percentage error and Theil’s index, the new model establishes its robustness in predicting electricity system behavior.

Acknowledging the limitations of traditional grey prediction models in capturing diverse growth patterns under fixed-generation orders, single structures and unadjustable background values, this study proposes a fractional grey intelligent prediction model with multiple parameter optimization. By incorporating multiple parameter optimizations and structure expansion, it substantiates the model’s superiority in forecasting provincial electricity consumption.

The opening up of B-share markets to domestic investors in 2001 is a landmark event in the development of the Chinese stock markets. This chapter aims to assess the possible changes in the market mechanism associated with this important event. A VECM-DCC-MVGARCH model is employed to investigate the market integration process in Chinese stock markets around the opening up of the B-share market to domestic investors. Our empirical results reveal that the Chinese stock markets were segmented before the opening up whereas they were integrated to some extent in the long-run after the opening up of B-share markets. Moreover, it is also found that A-share markets played a dominant role on the information flows between A-share and B-share markets; the short-run information flows between A-share and B-share markets were more rapid after the opening up of B-share markets.

Perhaps the most significant development in the global business arena in the post-war period has been the emergence of the Asia-Pacific rim countries as a significant economic force.

The purpose of this study is to identify the most influential factors affecting the printing properties and print quality of digitally printed silk fabrics in terms of colour strength and fixation percentage.

In this study, five factors (concentration of thickener, concentration of urea, concentration of alkali, pH of pretreatment liquor and steaming duration) were investigated using a blocked 2⁵⁻¹ fractional factorial experiment. The type of thickeners [polyacrylic acid and polyacrylamide (PAM)] were considered as a block.

Linear models were obtained and statistically tested using both analysis of variance and coefficient of determination (R²), and they were found to be accurate at 90 per cent confidence level. It was revealed that concentration of alkali, concentrations of urea and pH of the pretreatment liquor had an increasing effect on colour strength, whereas concentration of thickener and steaming duration showed decreasing effect on colour strength of digitally printed silk fabrics. Furthermore, concentration of alkali, concentrations of urea had increasing effect on dye fixation percentage, whereas steaming duration showed decreasing effect on dye fixation percentage of digitally printed silk fabrics. In addition, PAM thickener based pretreatment recipe exhibited better printing properties for the digitally printing of silk fabrics.

The main influences and significant two-factor interactions were discussed in detail to gain a better understanding of the printing properties of digitally printed silk fabrics. The findings of this study are useful for further optimisation of pre- and post-treatment processes for digital printing of silk fabrics.

This paper aims to propose an elementary approach toward the identification of assembly defects of a cam curved groove mechanism.

A numerical analysis method for identifying the assembly defects of the cam curved groove mechanism is proposed by resorting to Hertz contact theory. A general mathematical model is established to analyze the kinematic and dynamic characteristics with an interference fit between the main roller and cam curved groove, including the contact points of the external and internal ring.

The analysis method of the contact point characteristics of the cam curved groove mechanism is given in this paper, and the kinematic and dynamic characteristics of the main roller can be analyzed. The numerical examples presented in this paper are implemented in MATLAB, feasibility and validity of the above algorithm are verified by the finite element method.

Regarding the defects of the interference fit, the findings of this paper can serve as a reference for researchers in reducing the defects in the design process of the cam mechanism.