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The changes in the Antarctic sea ice area are directly related to the changes in the atmosphere and oceans. Determining the Antarctic sea ice distribution is of great significance to the global climate change analysis. The ant colony algorithm adopts a positive feedback mechanism to continuously converge the search process and ultimately approaches the optimal solution, making it easy to find the optimal segmentation threshold for detecting the sea ice distribution. However, the ant colony algorithm has the problems of high computational complexity and easy getting stuck in local optima. In order to better apply the ant colony algorithm to sea ice distribution detection, an improved ant colony algorithm was proposed, which improves the selection of initial clustering centers and the update of pheromone volatilization factors in the ant colony algorithm. We compared the improved ant colony algorithm with iterative algorithm, maximum entropy algorithm, and basic global threshold algorithm, and the results showed that the proposed algorithm is feasible. To further validate the accuracy of the improved ant colony algorithm, we compared the results obtained from MODIS data with the improved ant colony algorithm, iterative algorithm, maximum entropy algorithm, and basic global threshold algorithm for sea ice detection, and the results showed that the accuracy of the proposed algorithm was 4.99%, 3.66%, and 5.46% higher than the other three algorithms, respectively. [ABSTRACT FROM AUTHOR]

This paper presents the effect of the face camber ratio (FCR) on propeller performance, cavitation, and fuel consumption of a bulk carrier in calm water. First, using a developed propeller optimization model coupling a ship performance prediction tool (NavCad) and a nonlinear optimizer in MATLAB, an optimized propeller design at the optimal engine operating point with minimum fuel consumption is selected. This optimized propeller demonstrates superior fuel efficiency compared to the one selected by using the traditional selection methods that prioritize only higher propeller efficiency. Afterward, the FCR is applied to the propeller geometry to evaluate the effect on propeller performance. The open water curves of propellers with different FCRs ranging from 0% to 1.5% are computed based on empirical formulas and computational fluid dynamics (CFD) simulations. Between the two techniques, a good agreement is noted in verifying the predictions. Then, the open water curves from CFD models are implemented into NavCad to evaluate the overall hydrodynamic performance of the propeller at the design point in terms of efficiency, quantify reductions in fuel consumption, and analyze changes in cavitation and noise criteria. The computed results show a reduction in fuel consumption by 3% with a higher FCR. This work offers a preliminary evaluation of propeller performance-based FCR and shows its benefits. This technique offers a promising solution for improving the energy efficiency of the ship and lowering the level of fuel consumption and exhaust emissions. [ABSTRACT FROM AUTHOR]

The ferroelectric photovoltaic effect in BiFeO3 has attracted much attention recently. However, the potential of BiFeO3 as a photovoltaic material is limited due to its low photocurrent density and consequently low power conversion efficiency. Herein, a novel ferroelectric photovoltaic architecture based on the (Pr, Ni) gradient-doped BiFeO3-based thin film coupled with Au nanoparticles layer has been designed and fabricated. The experimental results and analysis show that this photovoltaic architecture exhibits extremely large photocurrent density (5.19 mA/cm2), which is about 472 times larger than that of pure BiFeO3 film (11 μA/cm2) and about 10 times larger than that of the conventional (Pr, Ni)-doped BiFeO3 film (0.54 mA/cm2). The enhanced photocurrent density should be attributed to the multifactorial coupling effect in this photovoltaic architecture, including the built-in electric field formed by the gradient distribution of oxygen vacancies, the flexoelectric effect and Local Surface Plasmon Resonance effect of Au nanoparticles. [ABSTRACT FROM AUTHOR]

In recent times, the fabrication of Z-scheme heterostructures has gained popularity as an effective strategy for developing composite catalysts with photogenerated carriers that possess high redox capacity. This study introduces a novel type of direct Z-scheme heterojunction photocatalysts known as ZnS quantum dots wrapped around CoWO4 nanoparticles (ZnS-QDs@CoWO4). The results of the experiments and analysis indicate that these heterojunction photocatalysts demonstrate superior degradation of tetracycline hydrochloride in wastewater compared with individual ZnS-QDs or CoWO4. Notably, the 30ZS-CWO catalyst, with a mass ratio of 30:1 between ZnS-QDs and CoWO4, exhibited the highest photocatalytic reaction rate constant (k = 0.03427 min–1), which is 3.5 times greater than that of ZnS-QDs (k = 0.00969 min–1) and 214 times higher than that of CoWO4 (k = 0.00016 min–1). The enhanced photocatalytic performance can be attributed to two main factors. First, the use of CoWO4 nanoparticles as carriers helps in better dispersing the ZnS quantum dots, leading to increased catalytic reaction sites. Second, the formation of Z-scheme heterojunctions in the composite photocatalysts significantly boosts the redox capability of the photogenerated carriers. Furthermore, the excellent stability and recyclability of ZnS-QDs@CoWO4 heterojunction photocatalysts were validated through five-cycle experiments. This research introduces a promising approach for developing QDs-based Z-scheme photocatalysts for highly effective environmental remediation. [ABSTRACT FROM AUTHOR]

This paper briefly introduces plant extracts and their combinations with sports drinks. The research involved 40 sportsmen who are affiliated with the Track and Field Department of the School of Physical Education in South-Central Minzu University. This paper aimed to explore the influence of sports drinks enhanced with extracts of Codonopsis pilosula and Acanthopanax senticosus on the endurance levels of long-distance runners. The participants were divided into four groups: a placebo group, a group receiving only C. pilosula , a group receiving A. senticosus , and a composite group. Endurance performance indices for long-distance running were evaluated both before and after the training. Before training, the heart rate, blood lactate level, and maximum oxygen uptake of the placebo group were 159.53 ± 2.21 times/min, 9.7 ± 1.2 mmol/L, and 66.18 ± 2.35 mL/kg/min, respectively; the single Codonopsis pilosula group was 158.33 ± 2.24 times/min, 9.6 ± 1.1 mmol/L, and 65.87 ± 1.88 mL/kg/min, respectively; the single Acanthopanax senticosus group was 159.66 ± 3.67 times/min, 9.7 ±1.0 mmol/L, and 66.32 ± 1.47 mL/kg/min, respectively; the Codonopsis pilosulae and Acanthopanax senticosus composite group was 158.21 ± 1.28 times/min, 9.6 ± 0.9 mmol/L, and 66.87 ± 1.12 mL/kg/min, respectively. After training, the corresponding values of the placebo group were 162.53 ± 3.21 times/min, 9.6 ± 0.8 mmol/L, and 68.85 ± 3.25 mL/kg/min, respectively; the single Codonopsis pilosula group was 145.33 ± 2.25 times/min, 9.1 ± 0.5 mmol/L, and 73.69 ± 2.58 mL/kg/min, respectively; the single Acanthopanax senticosus group was 142.66 ± 3.69 times/min, 9.1 ± 0.8 mmol/L, and 73.84 ± 2.19 mL/kg/min, respectively; the composite group was 131.21 ± 1.36 times/min, 8.3 ± 0.3 mmol/L, and 77.19 ± 3.14 mL/kg/min, respectively. Sports drinks that include extracts of C. pilosula and A. senticosus significantly increased endurance levels. The concurrent use of C. pilosula and A. senticosus was more beneficial in enhancing endurance performance for long-distance running in comparison to using each extract individually. [ABSTRACT FROM AUTHOR]

To improve the ride comfort of the vehicle and the high-efficiency control requirements of the suspension, this paper proposes a time-delay control strategy and the idea of using a linear motor as the actuator. This paper analyses the damping characteristics of the time-delay control strategy in the time domain and frequency domains. A linear equivalent excitation method is proposed to optimise the optimal time-delay control parameters under complex excitations. The stability of the system is analysed. The damping effect of time-delay control active suspension is verified by numerical simulation. An experimental hardware platform of a linear motor and active suspension was built further to verify the effectiveness of the time-delay control strategy. The experimental results show that the relative errors of root mean square values of experimental and simulation results are within 16% under each working condition. The experimental results verify the effectiveness of the simulation results. [ABSTRACT FROM AUTHOR]