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In response to the global challenge of climate change and the shift away from fossil fuels, the accurate prediction of wind power generation is crucial for optimizing grid operations and managing energy storage. This study introduces a novel approach by integrating the proportional–integral–derivative (PID) control theory into wind power forecasting, employing a three-dimensional gated neural (TGN) unit designed to enhance error feedback mechanisms. The proposed empirical mode decomposition (EMD)–convolutional neural network (CNN)–three-dimensional gated neural network (TGNN) framework starts with the pre-processing of wind data using EMD, followed by feature extraction via a CNN, and time series forecasting using the TGN unit. This setup leverages proportional, integral, and differential control within its architecture to improve adaptability and response to dynamic wind patterns. The experimental results show significant improvements in forecasting accuracy; the EMD–CNN–TGNN model outperforms both traditional models like autoregressive integrated moving average (ARIMA) and support vector regression (SVR), and similar neural network approaches, such as EMD–CNN–GRU and EMD–CNN–LSTM, across several metrics including mean absolute error (MAE), mean squared error (MSE), root mean squared error (RMSE), and coefficient of determination ( R 2 ). These advancements substantiate the model's effectiveness in enhancing the precision of wind power predictions, offering substantial implications for future renewable energy management and storage solutions. [ABSTRACT FROM AUTHOR]

Wind turbine blades, being flexible, are susceptible to damage during typhoons. Studying the aeroelastic response of these blades in typhoon conditions is crucial for providing a theoretical foundation for their optimization and design. This research focuses on the NREL 5 MW flexible blade, employing the B-L stall model for dynamic inflow and geometrically exact beam theory to develop an aeroelastic model capable of predicting the blade's flutter limit. Through quantitative analysis, we assess the stability of the wind turbine's flexible blade under typhoon conditions and examine the blade tip's transient response. The findings indicate that the model's flutter speed is 21.5 rpm, marked by a significant increase in tip deflection's mean square error of over 80% and a coupling of flapwise and torsional modes at 4.81 Hz. The blade tip's transient response under typhoon conditions does not satisfy the flutter criterion, thus preventing instability. Under typhoon conditions, the deflection in the flapwise, edgewise, and twist directions of the blade shows an increase of 12.1%, 10.5%, and 119.2%, respectively, compared to standard operating conditions. [ABSTRACT FROM AUTHOR]

Styphnolobium japonicum L. is a commonly consumed plant in China, known for its medicinal and nutritional benefits. This study focuses on the medicinal properties influenced by flavonoid metabolites, which vary during flower development. Utilizing full-length transcriptome sequencing on S. japonicum flowers, we observed changes in gene expression levels as the flowers progressed through growth stages. During stages S1 and S2, key genes related to flavonoid synthesis (PAL, 4CL, CHS, F3H, etc.) exhibited heightened expression. A weighted gene co-expression network analysis (WGCNA) identified regulatory genes (MYB, bHLH, WRKY) potentially involved in the regulatory network with flavonoid biosynthesis-related genes. Our findings propose a regulatory mechanism for flavonoid synthesis in S. japonicum flowers, elucidating the genetic underpinnings of this process. The identified candidate genes present opportunities for genetic enhancements in S. japonicum, offering insights into potential applications for improving its medicinal attributes. [ABSTRACT FROM AUTHOR]

Measuring the distribution of the fishing effort of trawlers is of great significance for describing marine fishery activities, quantifying fishing systems in terms of marine ecological pressure, and revising the regulations of fishing. The purpose of this paper is to develop an efficient learning algorithm to detect the fishing behavior of trawlers to analyze the distribution of fishing effort. The vessel-monitoring system data of more than 4600 trawlers from September 2019 to April 2023 were used for feature extraction. According to the spatiotemporal information provided by the vessel position data, 11-dimensional features were extracted to form the feature vectors. A Slime Mould Algorithm-optimized Light Gradient-Boosting Machine (SMA-LightGBM) algorithm was proposed to classify the feature vectors to recognize fishing behavior. The presented method showed a remarkable generalization ability and high accuracy, sensitivity, specificity, and Matthews correlation coefficient in the test results, with scores of 98.23%, 98.75%, 97.75%, and 0.9646, respectively. Subsequently, the trained model was used to identify the fishing behavior of trawlers belonging to the coastal provinces of the Bohai Sea and the Yellow Sea in the sea area of 117 °   E ~ 132 °   E , 26 °   N ~ 41 °   N . The fishing effort was calculated and evaluated according to the fishing behavior recognition results. The mean absolute error was 0.3031 kW·h, and the coefficient of determination score was 0.9772. The thermal map of the fishing effort of the trawler was mapped, and the spatiotemporal characteristics were estimated in the region of interest from 2019 to 2023 with a spatial resolution of 1 8 degree × 1 8 degree. This method is an efficient way of analyzing the spatiotemporal characteristics of the fishing effort of trawlers. It provides a quantitative basis for the assessment of fishery resources and can inform fishing policies. [ABSTRACT FROM AUTHOR]

In the present study, we used the axis model in the spatial syntax approach to analyze the evolution of the water system in Suzhou, China, from the 13th to the 20th centuries and its relationship with the distribution of gardens in the city. The distribution of the authoritative mainstream gardens appeared to be directly affected by the water system, and the gardens located in the areas with high water integration in each period were well preserved. From the 13th to the 17th centuries, gardens in areas with high water integration were all owned by the government and the class with social authority. This was consistent with the patterns for the hierarchical distribution of traditional urban space in China. However, in the 19th century, the gardens in areas with high water integration were owned by the class with social authority and the merchant class, reflecting characteristics different from the traditional pattern. The temple gardens in commercial areas with high water system integration were well preserved. Given the disruption of the surrounding water system, their original isolation from the water system was averted, turning them into public areas for social and public activities. In the 13th and 17th centuries, gardens located in areas with high and low water system integration took advantage of the surrounding water systems for landscaping, demonstrating the gardening principle according to local conditions. However, in the 19th and 20th centuries, the water system decreased sharply in many areas, and gardens built in areas with high water system integration were no longer thus situated. Traditional techniques for diverting water into gardens gradually disappeared. This study revealed that the preservation of gardens in Suzhou was largely due to the pattern of their distribution in the urban structure, and the gardens preserved to date have benefited from their location relative to the urban spatial structure of the 19th century. Private gardens, which embody the elegant taste of the literati, strongly resisted the aesthetic invasion from commercialization, however, and were also developed and preserved. Their social and spatial attributes were transformed by commercialization, presenting a contradictory yet complementary relationship between traditional garden culture and commercial development in Suzhou. [ABSTRACT FROM AUTHOR]

ESG (Environmental, Social and Governance) is not only a comprehensive manifestation of sustainable development but also an influencing factor of economic benefits. This research focuses on evaluating the impact of environment (E), society (S) and corporate governance (G) on the corporate financial performance in China. As China is currently in the exploration stage of ESG, a socially approved ESG evaluation system has not yet been formed. This paper deliberately selected variables and composite methods for E, S and G and integrated them into the ESG index through learning from the western experience and Chinese actuality. Then, whether E, S, G and ESG have a significant positive impact on financial performance is evaluated through panel regression analysis based on a sample of 191 listed companies in the Yangtze River Delta of China from 2015 to 2020. The results show that E has a significant negative impact on corporate financial performance, G has a significant positive impact, and S has no significant impact. ESG performance has a less significant impact on accounting-based financial performance and no significant impact on market-based financial performance. This research will help understand the performance of ESG and promote ESG practices in China. [ABSTRACT FROM AUTHOR]

Methanol crossover is an important factor affecting the performance of direct methanol fuel cells (DMFCs). In this work, a novel membrane electrode assembly (MEA) is designed and prepared by adding a layer of graphene aerogel (GA) between the carbon powder microporous layer and the catalytic layer, which optimizes the methanol transport and improves the output performance of DMFC at high methanol concentrations. Compared to conventional carbon powder, the addition of GA increases the tortuosity of the anode in the through-plane direction; hence, methanol is diluted to a suitable concentration when it reaches the catalyst. The maximum power density of the novel MEA can reach 27.4 mW·cm−2 at a condition of 8 M methanol, which is 234% higher than that of the conventional electrode. The test results of electrochemical impedance spectroscopy (EIS) indicate that the addition of GA does not increase the internal resistance of the novel MEA and that the mass transfer resistance at high concentrations is significantly lower. The experimental results indicate that the output performance at high concentration can be significantly improved by adding a GA layer, and its practicability in portable devices can be improved. It also improves the stability of DMFC under long-term testing. [ABSTRACT FROM AUTHOR]

Poly(β-hydroxybutyrate-co-β-hydroxyvalerate) (PHBV) was modified with endic anhydride grafted poly(propylene carbonate) (EA–PPC), and then PHBV/EA–PPC composite polymers were prepared by melt blending under the catalysis of stannous octoate (Sn(Oct)2). The blends were characterized by an electronic universal testing machine, cantilever impact testing machine, and differential scanning calorimeter (DSC), as well as dynamic mechanical analysis (DMA) and field emission scanning electron microscopy (FESEM). Effects of the amount of Sn(Oct)2 on the mechanical properties, thermal properties, and morphology of the blends were discussed. The results showed that the addition of Sn(Oct)2 promoted the transesterification reaction between PHBV and EA–PPC, and the compatibility between PHBV and PPC was greatly improved. When the amount of Sn(Oct)2 was 3 wt%, the impact strength and elongation at break of the PHBV/EA–PPC blend increased from 3.7 kJ/m2 and 4.1% to 5.9 kJ/m2 and 387.5%, respectively, and there was no significant decrease in tensile strength. Additionally, four esterification reaction mechanisms for PHBV/EA–PPC blends were proposed. [ABSTRACT FROM AUTHOR]

Phosphating sesbania gum (DESG) was obtained by modifying sesbania gum (SG) with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and endic anhydride (EA). The structure of DESG was determined using Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance spectroscopy (1H-NMR). Flame-retardant polylactic acid (PLA) composites were prepared by melt-blending PLA with DESG, which acted as a carbon source, and ammonium polyphosphate (APP), which acted as an acid source and a gas source. The flame retardancy of the PLA composite was investigated using vertical combustion (UL-94), the limiting oxygen index (LOI) and the cone calorimeter (CONE) test. Thermal properties and morphology were characterized via thermogravimetric analysis (TGA) and field emission scanning electron microscopy (FESEM), respectively. Experimental results indicated that when the mass ratio of DESG/APP was equal to 12/8 the LOI value was 32.2%; a vertical burning test (UL-94) V-0 rating was achieved. Meanwhile, the sample showed a lowest total heat release (THR) value of 52.7 MJ/m2, which is a 32.5% reduction compared to that of neat PLA. Using FESEM, the uniform distribution of DESG and APP in the PLA matrix was observed. The synergistic effect of DESG and APP effectively enhanced the flame retardancy of PLA. Additionally, the synergistic mechanism of DESG and APP in PLA was proposed. [ABSTRACT FROM AUTHOR]

The structure of a catalyst layer (CL) significantly impacts the performance, durability, and cost of proton exchange membrane (PEM) fuel cells and is influenced by the catalyst ink and the CL formation process. However, the relationship between the composition, formulation, and preparation of catalyst ink and the CL formation process and the CL structure is still not completely understood. This review, therefore, focuses on the effect of the composition, formulation, and preparation of catalyst ink and the CL formation process on the CL structure. The CL structure depends on the microstructure and macroscopic properties of catalyst ink, which are decided by catalyst, ionomer, or solvent(s) and their ratios, addition order, and dispersion. To form a well-defined CL, the catalyst ink, substrate, coating process, and drying process need to be well understood and optimized and match each other. To understand this relationship, promote the continuous and scalable production of membrane electrode assemblies, and guarantee the consistency of the CLs produced, further efforts need to be devoted to investigating the microstructure of catalyst ink (especially the catalyst ink with high solid content), the reversibility of the aged ink, and the drying process. Furthermore, except for the certain variables studied, the other manufacturing processes and conditions also require attention to avoid inconsistent conclusions. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET) is an important part of surface–atmosphere interactions, connecting the transfer of matter and energy. Land surface heterogeneity is a natural attribute of the Earth's surface and is an inevitable problem in calculating ET with coarse resolution remote sensing data, which results in significant error in the ET estimation. This study aims to explore the effect and applicability of the evaporative fraction and area fraction (EFAF) method for correcting 1 km coarse resolution ET. In this study we use the input parameter upscaling (IPUS) algorithm to estimate energy fluxes and the EFAF method to correct ET estimates. Five ground stations in the midstream and downstream regions of the Heihe River Basin (HRB) were used to validate the latent heat flux (LE) calculated by the IPUS algorithm and EFAF method. The evaluation results show that the performance of the EFAF method is superior to that of the IPUS algorithm, with the coefficient of determination (R2) increasing, the root mean square error (RMSE) decreasing, and the mean bias error (MBE) decreasing by 17 W/m2 on average. In general, the EFAF method is suitable for correcting the deviation in LE estimated based on Sentinel data caused by land surface heterogeneity and can be applied to obtain accurate estimates of ET. [ABSTRACT FROM AUTHOR]

With the substantial increase in the capacity of grid-connected photovoltaic (PV) power, the adverse effects of its complex fault characteristics on grid relay protection are increasingly highlighted. Based on the introduction of the topology and the control strategy on low-voltage ride through of PV power, a theoretical solution method for solving the fault current of PV power is proposed by taking account of the DC bus voltage fluctuation, and a theoretical calculation model of its transient and steady state is established. The correctness of the theoretical results is verified by the numerical simulation results and low-voltage ride through (LVRT) experiment results. Furthermore, to gain a better understanding of the factors influencing PV power fault characteristics, the effects of several factors including proportional integral (PI) controller parameters, fault voltage sag depth, and PV power load level on PV power fault characteristics are analyzed by using simple variable method. The obtained results can provide a theoretical reference for the control parameter design and protection research of PV power. [ABSTRACT FROM AUTHOR]

The oxidation of the metal powder during the thermal spraying process usually leads to significant deterioration of the microstructure and performance of the coating. In order to isolate the metal powder from oxygen during the spraying process, the CoNiCrAlY-Al 2 O 3 core-shell structured powder with Al 2 O 3 as the shell was designed in this study. The influence of the core-shell structured powder on the microstructure and corrosion resistance of the HVOF coating has been studied in detail. The results show that the temperature field of the molten CoNiCrAlY powder during the spraying process is significantly changed by the Al 2 O 3 shell. The poor deformability of the CoNiCrAlY-Al 2 O 3 droplets leads to an increase in the porosity and unmelted particles of the coating. In addition, the significant difference is that the coating also maintains a high content of β-NiAl phase. The lower oxide content in the CoNiCrAlY-Al 2 O 3 coating indicates that the core-shell structured powder significantly inhibits the oxidation of the CoNiCrAlY core powder during the spraying process. The CoNiCrAlY-Al 2 O 3 coating exhibits high corrosion potential, passive film resistance, charge transfer resistance, and low corrosion current density in 3.5 wt.% NaCl solution, indicating that the coating has excellent corrosion resistance.