天津现代职业技术学院

This paper studies the sliding mode control problem for a class of continuous-time singular Markov jump systems with uncertainties in the derivative matrix. Firstly, an augmented system approach is employed to handle the uncertainties in the derivative matrix. Secondly, a mode-dependent integral-type sliding mode surface is designed for the augmented system. Considering that the parameters related to external disturbances and nonlinear terms may be unknown, an adaptive sliding mode control law is designed to ensure the reachability of the sliding mode surface. Furthermore, within the linear matrix inequality framework, a sufficient condition is formulated to ensure the sliding mode dynamics achieves both stochastic admissibility and compliance with dissipative performance. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed method.

The present study aimed to investigate the synergistic effects of nitric oxide combined with clove essential oil on the postharvest storage quality of peach fruit. The harvested peaches were treated with the sodium nitroprusside and clove essential oil using atomized fumigation. The firmness, ethylene release rate, decay index, titratable acid content, soluble solid content, cell wall polysaccharide contents, cell wall degradation enzymes activity, defense-related enzymes activity, tissue structure and cell wall ultrastructure were analyzed in peaches during the storage period at 0 ℃. The results indicated that the combined atomized fumigation treatment had a better preservation effect on peaches, in comparison with the nitric oxide or clove essential oil alone. The decay index of peach fruit treated with the combined treatment was only 9.25% during the 35 d of storage. The ethylene release rate of combined treatment was reduced by 34.88% while the firmness, titratable acid, and soluble solid contents of peaches fruit was increased by 22.01%, 31.68% and 5.90%, respectively, when compared to the untreated fruit on day 35. Furthermore, the combined treatment inhibited the activities of polygalacturonase, pectin methylesterase, cellulase and β-galactosidase activities. The water-soluble pectin content of combined treatment was reduced by 21.88% compared to the control group. The contents of chelate soluble pectin, sodium carbonate-soluble pectin, hemicellulose and cellulose components increased by 23.40%, 21.31%, 36.62% and 39.89% respectively, thereby maintaining the integrity of the cell wall structure and delaying the fruit softening. We found that combined treatment enhanced the defense enzyme activities of phenylalanine ammonia-lyase, and 4-coumarate coenzyme A ligase activities. Cinnamate-4-hydroxylase activity of combined treatment was 15.71% higher than that of the treatment with nitric oxide alone and 20.98% higher than that of the treatment with clove essential oil alone, enhancing the disease resistance of the fruit. Therefore, the nitric oxide combined with clove essential oil through atomized fumigation can effectively maintain the quality of peaches during low-temperature storage, providing a theoretical basis for the development of quality control technologies for postharvest peaches.

Evaluating the development level of the rural ecological environment is essential for promoting sustainable rural revitalization and improving environmental quality. This study develops a comprehensive evaluation framework for assessing rural ecological environment development using the Analytic Hierarchy Process. An index system consisting of four main dimensions as: ecological environment, ecological economy, ecological protection, and ecological living was established, including 16 representative indicators related to forest coverage, livestock waste treatment, fertilizer and pesticide application, drinking water quality, rural income, and ecological agriculture. Indicator weights were determined through expert consultation and consistency testing, while gray relational analysis was applied to evaluate the contribution and correlation degree of each indicator. The results indicate that ecological economy exhibited the highest weight (0.4839), followed by ecological environment (0.2736), ecological living (0.1371), and ecological protection (0.1054). Among the individual indicators, fertilizer application, livestock manure treatment rate, and drinking water qualification rate showed the strongest influence on rural ecological environment development. The findings reveal that excessive agrochemical use, insufficient ecological protection measures, and inadequate rural environmental infrastructure remain the main constraints affecting sustainable rural development. Based on the evaluation results, targeted improvement measures are proposed, including optimization of environmental monitoring systems, promotion of ecological agriculture, application of advanced monitoring technologies, and enhancement of rural environmental governance mechanisms. The proposed evaluation framework provides a practical decision-support tool for assessing rural ecological environment quality and supporting sustainable rural development strategies.

In order to investigate the effect of ozone regulation on the color and quality changes of nectarine treated with 1-methylcyclopropylene (1-MCP) during cold storage, nectarine test materials were fumigated with 1 μL/L 1-MCP for 24 h after postharvest, combined with ozone water atomization and ozone gas fumigation for 30 min, then packaged and stored at 0±0.5 ℃. The relevant physicochemical indexes were determined regularly. Results showed that 1-MCP combined with ozone treatment could effectively inhibit respiration rate and ethylene release, 1-MCP alone inhibited anthocyanin accumulation in pulp, hindering its red coloring, and 1-MCP combined with ozone treatment promoted red coloring in pulp at the later stage of storage. Compared with 1-MCP group alone, 1-MCP group combined with ozone treatment had higher anthocyanin content, centaurin-3-O-glucoside content, centaurin-3-O-rutin content and enzyme activity related to anthocyanin metabolism at the later stage of storage. Meanwhile, ozone gas fumigation was more conducive to anthocyanin accumulation at the later stage of storage, and the flesh red degree was higher. This study provides a new idea for improving the control of postharvest color and optimizing the application of 1-MCP in postharvest preservation.

With the widespread application of drone technology, energy management of drone swarms has become a key challenge in ensuring sustained and efficient operations. To optimize the energy consumption of drone swarms, researchers have proposed the energy balance plane routing algorithm. This algorithm uses ultraviolet light for low visibility communication and has shown promising results in managing the energy of drone swarms. To address the issues of uneven cluster head distribution and reduced energy consumption in other algorithms, an improved non-uniform clustering energy balancing routing algorithm is proposed. Compared to existing algorithms, the improved non-uniform clustering energy balancing routing algorithm achieved the lowest average communication consumption among 5 nodes and prolonged node failure time. The performance of the research method has been verified through simulation experiments, which is of great significance in maintaining energy consumption balance and can improve the energy efficiency and sustainability of the network. This study can provide more effective solutions for the development and application of drone technology, promoting its widespread application and promotion in various fields.