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Abstract 5G base stations (BSs) are potential flexible resources for power systems due to their dynamic adjustable power consumption. However, the ever‐increasing energy consumption of 5G BSs places great pressure on electricity costs, and existing energy‐saving measures do not fully utilise BS wireless resources in accordance with dynamic changes in communication load, resulting in flexible resource waste and seriously limiting electricity cost savings for 5G BSs. A multi‐BS cooperation self‐optimising sleep strategy for 5G BSs that consists of an initial user association stage based on multi‐BS cooperation (MBSC) and a self‐optimising variable‐threshold sleep stage (SVTS). First, a heterogeneous cellular network (HCN) model is established. Then, a 5G BS economic optimisation model is constructed, which aims at minimising the electricity cost of the BSs and takes the BS and user equipment (UEs) states in the HCN model as constraints to clarify the optimisation objective and constraints for the proposed strategy. Furthermore, BSs are initially associated with UEs through MBSC, and idle and lightly loaded BSs are then maximally put to sleep through SVTS to reduce power and energy consumption and thereby realise economic optimisation of the BSs. Finally, simulations are conducted to validate the proposed strategy and illustrate the ability of 5G BSs to provide flexible resource regulation for power systems.

Abstract Addressing the significant discrepancy between actual experimental cutting force and its predicted values derived from traditional constitutive model parameter identification methods, a reverse identification research of the Johnson–Cook (J-C) constitutive model for 304 stainless steel was conducted via genetic algorithm. Considering actual cutting zone and the influence of feed motion on the rake (flank) angle, an unequal division shear zone model was established to implement the theoretical calculation for shear zone stress. Through cutting experiments, the spindle speed was negatively correlated with the cutting force at first, and then became positively correlated; The empirical formula (EXP model) for turning force was corrected, revealing that the EXP model was unable to provide optimal predicted values for cutting force. The influence of the J-C constitutive parameter C on the cutting morphology was firstly investigated through simulation analysis, and determined an appropriate value for C, then obtained the precise values for the other four constitutive parameters by genetic algorithm. Moreover, the simulated values of cutting force in JC1 model (obtained from the Split Hopkinson Pressure Bar test) and JCM model (the improved model using genetic algorithm) were obtained by three-dimensional (3-D) simulation via FEM software. The results indicated that, the maximum error between actual experimental cutting force and its simulated values (by JCM model) was 14.8%, with an average error of 6.38%. These results outperformed the JC1 and EXP models, suggesting that the JCM model identified via genetic algorithm was more reliable.

The explosive growth of mobile data traffic has resulted in a significant increase in the energy consumption of 5G base stations (BSs). However, the existing energy conservation technologies, such as traditional BS sleep strategy, rarely consider the dynamic real-time changes of users (UEs), which may make it difficult to maximize sleep idle or lightly loaded BSs, thereby affecting the reduction of BS energy consumption. Therefore, an energy consumption optimization strategy of 5G BSs considering variable threshold sleep mechanism (ECOS-BS) is proposed in this paper. Compared to current strategies, the ECOS-BS strategy can dynamically adjust BSs’ optimal sleep threshold on the premise of considering UEs’ dynamic changes, which is conducive to maximize sleep available BSs and realize the optimal management of BS energy consumption. Taking a heterogeneous cellular network as an example, numerical simulations are conducted to validate the effectiveness of the proposed strategy.

In an attempt to characterize the non-linear augmentation of stress as a function of strain during the compression molding process of the straw-potato residue mixture, and to analyze the impact of elasto-visco-plastic deformation on energy consumption and product quality, the present study has established an elasto-visco-plastic constitutive model for the straw-potato residue mixture based on stress-strain test data. The model parameters were obtained through curve fitting, including the elastic modulus E, viscous coefficient K, viscous index n, friction stress σf, and plastic coefficient R1/m. The effects of test factors such as moisture content, feeding amount, compression temperature, and compression speed on these model parameters were analyzed to decipher the elasto-visco-plastic deformation process of the mixture. Additionally, specific energy consumption (SEC) and relaxation ratio (Rr) were employed as test indicators and were subjected to correlation analysis with the model parameters, culminating in the establishment of a multivariate regression equation. The results indicate that the correlation between SEC and the model parameters is quite significant under different test conditions, while Rr is significantly correlated with n, σf, and R1/m only under different moisture contents. This suggests that the energy consumption in the molding of the straw-potato residue mixture is primarily due to overcoming the resistance of elasto-visco-plastic deformation and friction, while the quality of the molding is mainly influenced by the moisture content, thereby establishing a connection with the elasto-visco-plastic parameters. The multivariate regression equation ultimately derived can be used to discern the degree of influence of elastic deformation, viscous deformation and plastic deformation on the specific energy consumption during the compression of the straw-potato residue mixture.

Objective: The contents of main active ingredients, antioxidant and cholate binding ability of different ethanol extracts from Psoralea corylifolia L. were explored based on the mode of correlation of “components-efficacy”. Methods: Psoralea corylifolia L. was extracted with anhydrous ethanol, 75% ethanol, 50% ethanol and water. The contents of total flavonoids and total polyphenols in Psoralea corylifolia L. were determined. The antioxidant and lipid-lowering activities in vitro of Psoralea corylifolia L. were evaluated by three antioxidant systems and the binding ability of cholate salts, respectively, and the correlation analysis was conducted. Results: The contents of total flavonoids and total polyphenols in anhydrous ethanol extract were the highest, (50.317±0.018) mg/g and (3.860±0.045) mg/g, respectively. The 50% ethanol extract showed the best ability to scavenge ABTS＋· and DPPH·, the IC50 values were 0.76 and 1.63 mg/mL, respectively. The anhydrous ethanol extract showed the strongest reducing ability, the A0.5 value was 2.63 mg/mL. The water extract showed the strongest binding capacity to sodium cholate, the IC50 value was 0.67 mg/mL. The 50% ethanol extract showed the strongest binding capacity to sodium taurocholate and sodium glycinate, the IC50 values were 1.26 and 0.41 mg/mL, respectively. The correlation results showed that the content of total flavonoids of different ethanol extracts from Psoralea corylifolia L. had a significant positive correlation with DPPH· clearance rate and sodium taurocholate binding rate (P

To optimize the ultrasound-assisted three-phase partitioning for the simultaneous extraction of allicin and polysaccharides from garlic. The effect of polyethylene glycol (PEG) concentration, ammonium sulfate concentration, sonication temperature, and sonication time on the extraction efficiency of allicin and polysaccharides were investigated, respectively. The simultaneous extraction process conditions of allicin and polysaccharides were optimized according to the Box-Behnken experimental design. Results showed that the optimal conditions were PEG concentration of 24%, the ultrasonic temperature of 34 °C, and ultrasonic time of 50 min. Under these conditions, the extraction efficiency of allicin and polysaccharide was calculated according to the anhydrous calculation, reaching 3.564 and 43.86 mg/g, respectively. The optimized extraction process could effectively and simultaneously extract allicin and polysaccharides from garlic, which would provide a foundation for the deep research, development, and application of functional products from natural garlic.

Multi-objective optimal dispatching schemes with intelligent algorithms are recognized as effective measures to promote the economics and environmental friendliness of microgrid applications. However, the low accuracy and poor convergence of these algorithms have been challenging for system operators. The bird swarm algorithm (BSA), a new bio- heuristic cluster intelligent algorithm, can potentially address these challenges; however, its computational iterative process may fall into a local optimum and result in premature convergence when optimizing small portions of multi-extremum functions. To analyze the impact of a multi-objective economic–environmental dispatching of a microgrid and overcome the aforementioned problems of the BSA, a self-adaptive levy flight strategy-based BSA (LF–BSA) was proposed. It can solve the dispatching problems of microgrid and enhance its dispatching convergence accuracy, stability, and speed, thereby improving its optimization performance. Six typical test functions were used to compare the LF–BSA with three commonly accepted algorithms to verify its excellence. Finally, a typical summer-time daily microgrid scenario under grid-connected operational conditions was simulated. The results proved the feasibility of the proposed LF–BSA, effectiveness of the multi- objective optimization, and necessity of using renewable energy and energy storage in microgrid dispatching optimization.

The development and application of new configurations inspired by the folding principle of origami is increasingly becoming a research hotspot in related fields. Among them，the design of plane crease，the folding of three-dimensional shape，the motion characteristics of configuration，the degree of freedom and the corresponding driving design are all scientific problems to be solved. Based on the classic Water-Bomb origami basic unit，the plane crease of the non-convergence foldable unit with single degree of freedom is designed. The combination design and three-dimensional （3D） folding design of the basic crease are carried out，and two kinds of 3D units with certain stiffness and folding motion are obtained，namely the foldable prismatic pair and the foldable rotation pair. At the same time，inspired by the foldable rotation pair，a software actuator cooperating with the basic non-convergence unit is designed，and combined with two kinds of 3D units，a stable control of the 3D units is realized. In the experiment，it is found that the control of the input angle of the 3D unit by the software actuator can control the stiffness of the 3D unit simultaneously. The origami leg and walking robot are designed by connecting the two kinds of three-dimensional units in series，and the walking simulation experiment and the step crossing experiment of the robot are implemented. The maximum margin of the origami leg of crossing the step is obtained，and the special performance of the two kinds of variable stiffness units in the process of walking and stepping is verified.