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With the promotion of the Carbon Peaking and Carbon Neutrality Goals, wind, photovoltaic, hydro, thermal, and other power generation sources coexist in the power system. Therefore, the study of various energy synergistic frequency modulation (FM) methods is particularly important. A multi-objective two-layer game optimization model for wind, photovoltaic, hydro, and thermal power considering FM revenue, FM speed, and FM accuracy is proposed for the requirements of "two rules." The upper layer constructs a hierarchical mixed-strategy game with three objective functions as game participants and solves it using the evaluation factors in conjunction with the NSGA-III multi-objective optimization algorithm to solve the problem, and sets the objective preference through the evaluation factors, so as to obtain the system revenue and the FM power allocation for each energy unit. The lower layer involves wind, photovoltaic, hydro, and thermal power units as participants in the game to establish a cooperative alliance. It integrates the data generated by the upper layer model and utilizes the improved Shapley value algorithm based on the entropy value method to calculate the revenue distribution for each energy unit, considering the FM output, FM speed, and FM accuracy. Based on the automatic generation control data in an inland area, the simulation results confirm that the multi-objective two-layer game optimization model proposed in can enhance the FM speed and FM accuracy of the system, as well as increase the FM revenue of the system and each unit. The results of this work provide useful references for the improvement of power system economic efficiency, the enhancement of responsiveness and stability, and the coordinated and optimized operation of the source-grid side.

The uncertain power flow analysis is essential to assessing the operating states of distribution networks under various uncertainties. The power flow calculations considering the single uncertainty have been well developed. However, different types of uncertainties may coexist in power systems. In order to comprehensively assess the impacts of mixed uncertainties, this paper proposes a surrogate-assisted point estimate method to solve the hybrid probabilistic and interval power flow. By taking advantage of the point estimate method and high-fidelity surrogate model, the proposed method can accurately obtain the relevant results of power flow calculation with high efficiency. The numerical studies in IEEE 33-bus and 141-bus systems verify the accuracy and efficiency of the proposed method by comparing it with other well-known methods.

The excessively high temperature of gearbox oil in summer leads to power reduction of wind turbines (called high-temperature power reduction state), which does harm to the performance of the power generation performance of the wind turbine. The timely and accurate identification of high-temperature power reduction state will contribute to improving the operation efficiency of the unit. This study proposes a new method based on the vine copula model and algorithm of convolutional neural network cascading to the bidirectional long short term memory network with attention mechanism (CNN-BiLSTM-attention). Firstly, the vine copula model is used to analyze the correlation of the features in supervisory control and data acquisition (SCADA) system, and the features that can reflect the high-temperature power reduction state are extracted comprehensively. Secondly, CNN is used to mine the coupling relationship between features and extract deep spatial features. Finally, BiLSTM is used to extract the time-series information in the depth spatial feature further for high-temperature power reduction state identification, and the attention mechanism is introduced to sense and identify the relevant network weights adaptively to enhance the influence of important information. The experimental results show that the method has high identification accuracy in the identification of high-temperature power reduction state. Accurate and reliable identification results can provide reference for formulating the operation and maintenance scheme of wind turbine reasonably.

The intrinsic clustering behavior and kinetically sluggish conversion process of lithium polysulfides seriously limit the electrochemical reversibility of sulfur redox reactions in lithium-sulfur (Li-S) batteries. Here, we introduce molybdenum pentachloride (MoCl5) into the electrolyte which could coordinate with lithium polysulfides and inhibit their intrinsic clustering behavior, subsequently serving as an improved mediator with the bi-functional catalytic effect for Li2S deposition and activation. Moreover, the coordination bonding and accelerated conversion reaction can also greatly suppress the dissolution and shuttling of polysulfides. Consequently, such polysulfide complexes enable the Li-S coin cell to exhibit good long-term cycling stability with a capacity decay of 0.078% per cycle after 400 cycles at 2 C, and excellent rate performance with a discharge capacity of 589 mAh/g at 4 C. An area capacity of 3.94 mAh/cm2is also achieved with a high sulfur loading of 4.5 mg/cm2at 0.2 C. Even at -20°C, the modified cell maintains standard discharge plateaus with low overpotential, delivering a high capacity of 741 mAh/g at 0.2 C after 80 cycles. The low-cost and convenient MoCl5additive opens a new avenue for the effective regulation of polysulfides and significant enhancement in sulfur redox conversion.

Li1.6Mn1.6-xCrxO4was synthesized by hydrothermal reaction followed by acid leaching to form lithium ion sieve. The structure, morphology and composition were examined using X-ray diffraction, SEM and EDS. The influences of Cr doping content and hydrothermal temperature on Li+adsorption capacity and manganese dissolution ratio were investigated. The result indicates that Cr is incorporated into the spinel structure with cell contraction when x = 0.08. Li1.6Mn1.6-xCrxO4shows Li+adsorption capacity of 31.67 mg/g and Mn dissolution ratio of 2.1% when x is 0.016 at 270 °C. After 20 cycles in salt lake brine, the Mn dissolution ratio and Li adsorption capacity is 0.35% and 25.5 mg/g, respectively. The Cr-doped ion-sieve shows improved adsorption capacity, retention and structural stability compared with the undoped lithium ion-sieve. The adsorption process for the Cr-doped ion-sieve follows a pseudo-second-order kinetic model.Li1.6Mn1.6-xCrxO4was synthesized by hydrothermal reaction followed by acid leaching to form lithium ion sieve. Li1.6Mn1.6-xCrxO4show Li+adsorption capacity of 31.67 mg/g and Mn dissolution ratio of 2.1% when x is 0.016. After 20 cycles in salt lake brine, the Cr-doped ion-sieve shows higher adsorption capacity retention and structural stability compared with the undoped one.

To address the challenges of complex modeling and control objective conflicts, a game control scheme based on data‐driven and reliability awareness is proposed for floating offshore wind turbines (FOWTs). In this scheme, first, an enhanced model‐free adaptive control method with the integration of iterative learning is proposed, which utilized online data for driving modeling and control command derivation to ensure the functionality of the FOWT and maintain stable power generation. Then, a healthy reliability‐aware model of the pitching system is developed and integrated into the controller of FOWTs. Finally, a trade‐off between the reliability and functionality of FOWTs is intelligently made through bargaining game theory to derive reasonable control commands. Simulation experiments of the proposed control scheme are carried out using FAST under different wind conditions. The results show that, compared with the gain‐scheduled PI controller and model‐free adaptive controller, the output power of the proposed controller is more stable and the pitch motion of the FOWT is significantly reduced; compared with the improved model‐free adaptive controller, the proposed controller improves the reliability of the pitch system. A model‐free control strategy that considers both the functionality and reliability of floating offshore wind turbines (FOWTs) is proposed to address the challenges of complex modeling and control objective conflicts. The control problem of FOWTs is transformed into a game problem, and the optimal control scheme that balances functionality and reliability is obtained through bargaining game.

•Mn was recovered as lithium ion-sieve from leaching solution of spent LIBs.•Mn was separated from Ni and Co with D2EHPA extraction following two-step stripping.•Co doping improves structure stability and adsorption capacity of lithium ion-sieve.

The intermittency and fluctuations of wind power cause problems in integration of wind energy systems into the grid. To smooth the fluctuations of wind power, a control scheme based on fuzzy empirical mode decomposition (EMD) is proposed with the use of battery energy storage system (BESS). With this idea, the wind power signal is decomposed via EMD and filtered into two parts: the low-frequency part is taken as the target smooth wind power for grid connection, and the high-frequency part is stored by BESS before connecting to the grid to compensate for the fluctuations in the original wind power signal. A fuzzy EMD filter is developed by considering constraints on both the power fluctuation rate and the state of charge (SOC) of the BESS. The performance of the proposed strategy has been examined through case study simulations, which demonstrates improvement in mitigating wind power fluctuations and also in reducing over charging/discharging operations of the integrated BESS.

The shuttle effect and sluggish electrochemical conversion of polysulfides have been believed to strongly influence the performances of lithium-sulfur (Li-S) batteries. Herein, we propose the synthesis of nano-sized MoxC electrocatalysts embedded on N-doped graphene and develop its application for separator modification of Li-S batteries. The N-doped graphene provides a two-dimension conductive barrier layer to chemically adsorb polysulfides and inhibit polysulfides diffusion, while MoxC nanoparticles could serve as the functional electrocatalyst to facilitate the redox kinetics of the multiphase conversion. The Li-S coin cells with MoxC@N-rGO modified separator can exhibit good long-term cycling stability with a capacity decay of 0.069 % per cycle after 400 cycles at 0.5 C, and excellent rate performance with a discharge capacity of 653 mAh g-1at 4 C. An area capacity of 4.5 mAh cm-2is also achieved with a high sulfur loading of 5.2 mg cm-2and a low electrolyte/sulfur ratio of ∼5 μL mg-1.

Gold dissolution in acidic solutions containing thiourea (Tu) and thiocyanate was studied using linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). In the presence of Tu, but in the absence of thiocyanate, passivation of gold occurred due to thiourea adsorption. When the solution also contained thiocyanate, passivation was significantly alleviated and gold dissolution enhanced. EIS revealed only one capacitive loop at 0.3 and 0.4V vs. SCE. The combination of the lixiviants lowered the polarization resistance for gold dissolution. A molar SCN:Tu ratio of 5:1 produced the lowest polarization resistance.

•The types and integration modes of electric vehicles in virtual power plants are compared and analyzed.•Uncertainties and constraints associated with electric vehicles in virtual power plants are summarized comprehensively.•Operational control methods of electric vehicles in virtual power plants are classified and reviewed in detail.•The real cases and the future trend of electric vehicles in virtual power plants are studied and analyzed.

As the most important daily management work in power application, electrical energy metering is carried out throughout the whole process of power production, transmission and use. Ensuring the accurate and reliable operation of electric energy measurement is the key to establish a fair, just and orderly electric power marketing market. At present, there are many problems in the inspection process of electric power measurement device, which include large workload, long verification time, sampling accuracy and algorithm performance constraints. In this paper, the remote on-line diagnosis of electrical energy metering decice is studied. Based on a large amount of sampling datas of power measurement, voltage and current, it introduces the parallel computing in data mining. Based on support vector machine, data and task parallelization fault diagnosis modelsare established,the online real-time monitoring and failure warning for electric power measurement device is realized, which contains abnormal characteristics and fault state. The visualization method is used to upload the device failure pictures in time and the diversified fault early warning technology is adopted, in order that the staff can timely analyze the electrical energy metering device in the fault or abnormal condition. In this way, the remote state monitoring and operation management level of the electrical energy metering device are improved.

The article reports that New Mexico Governor Bill Richardson is contemplating about granting Billy the Kid, the outlaw cattle rustler and murderer who died in 1881, clemency due to evidence that the Governor at the time told the criminal that he would receive a pardon if he testifies about a murder he had witnessed.

The article focuses on the role of technology in contributing to an increasing number of false alarms and foolish risks at national parks in the U.S. according to rangers.

The article presents statistics on a variety of topics as of October 2010, including the estimated number of children who are forced to serve as soldiers all over the world, the number of live reptiles discovered in a suitcase of a wildlife smuggler at an airport in Malaysia in August and the estimated number of illegal aliens in the U.S.

The article reports on a new approach initiated by some airports in Germany to monitor the quality of air, in which they use bees as biodetectives by testing their honey for toxins regularly.

The article focuses on the physical-training program of the U.S. Army which includes exercises like yoga or Pilates routines and aims to reduce injuries and better prepare soldiers for combat in rough terrain, and the report "Too Fat to Fight," which blames the problem of excess weight among potential recruits on junk foods, video games, and fewer gym classes in some high schools.

The article focuses on the Chinese dating television show "If You Are the One," which got a makeover after government censors declared it vulgar and blamed it for promoting materialism.

The article focuses on a remote-controlled humanoid robot teacher called Saya, which was tested in a classroom in Tokyo, Japan in 2010.

The article focuses on flag football, which is among the fastest-growing varsity sports for high school girls in Florida, and an issue raised by a lawyer for the National Women's Law Center over whether the sport provides girls similar educational opportunities as boys.

Gold dissolution in acidic solutions containing thiourea (Tu) and thiocyanate was studied using linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). In the presence of Tu, but in the absence of thiocyanate, passivation of gold occurred due to thiourea adsorption. When the solution also contained thiocyanate, passivation was significantly alleviated and gold dissolution enhanced. EIS revealed only one capacitive loop at 0.3 and 0.4V vs. SCE. The combination of the lixiviants lowered the polarization resistance for gold dissolution. A molar SCN:Tu ratio of 5:1 produced the lowest polarization resistance.