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Based on the measured fracture production of the rock body in the field, the disc fracture hypothesis is used to generate three groups of fractures to form a fracture network by the Monte-Carlo method. The three-dimensional fracture network is simplified into a spatial one-dimensional pipe element model based on the hypothesis of water channel flow in the fractures, and the equivalent pipe diameter of the pipe element is considered to be linearly related to the fracture width. The equivalent permeability tensor is obtained by using a genetic algorithm to obtain the ratio of the equivalent pipe diameter to aperture size for each group of fissures, and compared with the equivalent permeability tensor obtained by the overall single-parameter model and direct algorithm. In comparison with the measured permeability tensor, it is concluded that the multiparameter model can better characterize the permeability tensor than the single-parameter model.

We address weighted composition operators between Bers-type spaces on generalized Hua–Cartan–Hartogs domains and provide the necessary and sufficient conditions for their boundedness and compactness. We then apply our results to study the boundedness and the compactness of weighted composition operators between Bers-type spaces on four different domains: generalized Hua domains, generalized Cartan–Hartogs domains, generalized Cartan–Hartogs domains over different Cartan domains and generalized ellipsoidal-type domains, by proving that the above four different domains are special cases of the generalized Hua–Cartan–Hartogs domains. [ABSTRACT FROM AUTHOR]

The denim fabric industry has experienced exponential growth and escalating concerns regarding sustainable production and recycling practices. The wide utilization of indigo dye in denim manufacturing presents significant challenges owing to its intricate chemical structure and inherent resistance to degradation. Improper disposal of waste denim fabric and the release of indigo dye impose severe ecological ramifications. In this study, we explore the productive application of electrochemistry to recycle indigo dye from waste denim fabric while repurposing the electrolyte for denim dyeing. Notably, the separation of indigo from waste denim textiles reaches 82.34%. It is calculated that 21.59 g of indigo can be recovered from 1 kg of denim waste. Recovered indigo can be reused for cotton yarn dyeing. In the experiment, indigo was recovered from 0.03 square meters of denim waste, and the K / S value of the yarn was up to 2.997 after five dyeing cycles. The loss of fabric strength after recycling is as low as 13.32%, which has little effect on secondary fabric recycling. Our recycling method reduces the waste of 978.41 g of waste fabric and 21.59 g of indigo per kilo compared to conventional treatment. This research provides compelling scientific evidence supporting adopting a closed-loop system within denim production, underlining the potential for environmentally conscious and economically viable practices in the industry. [ABSTRACT FROM AUTHOR]

To solve the control problem of time-varying state-scale nonlinear systems whose initial state is not affected by settling time, fixed-time convergence algorithms are proposed for first-order systems and higher-order systems in this paper. First, a scalar model is used to illustrate how the time-varying feedback parameter can guarantee that the system achieves asymptotic stability while achieving finite-time convergence, and it is proved that the settling time obtained in this paper is only related to the prescribed boundary. This allows us to design the settling time with an appropriate parameter based on the prescribed boundary. To exhibit the effectiveness and extensibility of the proposed algorithm for first-order scalar systems, the results are subsequently extended to general higher-order systems based on the backstepping method. By introducing numerical simulation results, this paper verifies that the proposed algorithm will make the system achieve asymptotic stability and its output can converge to a given boundary, regardless of the system's initial states. [ABSTRACT FROM AUTHOR]

The energy hub provides a comprehensive solution uniting energy producers, consumers, and storage systems, thereby optimizing energy utilization efficiency. The single integrated energy system's limitations restrict renewable absorption and resource allocation, while uncoordinated demand responses create load peaks, and global warming challenges sustainable multi-energy system operations. Therefore, our work aims to enhance multi-energy flexibility by coordinating various energy hubs within a hydrogen-based integrated system. This study focuses on a cost-effective, ecologically sound, and flexible tertiary hub (producer, prosumer, and consumer) with integrated demand response programs, demonstrating a 17.30% reduction in operation costs and a 13.14% decrease in emissions. Power-to-gas technology enhances coupling efficiency among gas turbines, boilers, heat pumps, and chillers. A mixed-integer nonlinear programming model using a GAMS BARON solver will achieve the optimal results of this study. The proposed model's simulation results show reduced energy market costs, total emissions, and daily operation expenses. [ABSTRACT FROM AUTHOR]

Based on the problem of nickel remove from ferrous sulphate solution with low nickel content, it was Investigated by on exchange process in this paper. Different factors, including resin tilting capacity, pH, time, initial nickel content and so on, were investigated to explore the performance of nickel remove from ferrous sulphate solution by designed experiments. The resutts indicate that priority se1ectivity for nickel ss presented in ferrous sulphate solution after resin adsorption and the operating capacity of CH-90 resin for nickel ss 15 mg/g. After resin adsorption,Fe/Ni molar ratio ss increased from 17 : 1 to 93 : 1 and removal rate on nickel reached 87%. Additiona11y,nickel content ss reduced to 0. 3 g/L. In other words,nickel ss removed effectually from ferrous sulphate solution. The adsorption isotherms and adsorption kinetics were evaluated by changing the initial content and adsorption reaction time. It was found that the resin was in tine with the Langmuir adsorption ssotherm,and met the quasi-second-order kinetic equation. Furthermore,adsorption process was mainly controlled by on exchange. [ABSTRACT FROM AUTHOR]