A proposed method for diagnosing sensor faults in the stator winding temperature sensor of a wind turbine is introduced, aiming to address the significant issues that arise when such malfunctions occur, affecting the ...
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A proposed method for diagnosing sensor faults in the stator winding temperature sensor of a wind turbine is introduced, aiming to address the significant issues that arise when such malfunctions occur, affecting the overall stable operation of the turbine. The method combines supervisory control and data acquisition (SCADA) with an improved firefly sparrow search algorithm (FISSA)-optimized deep belief network (DBN). The input parameters of the model are determined via Pearson's correlation coefficient method, whereas the exponentially weighted moving average (EWMA) is utilized to detect faults. To ensure system stability in the event of sensor failure, a multi-input single-output sensor fault data reconstruction model is proposed on the basis of long-term and short-term memory (LSTM) networks, which are further optimized using the seagull optimization algorithm (SOA-LSTM). An illustrative verification is subsequently conducted using actual data obtained from a wind farm located in Central china. The results of the verification demonstrate that the proposed method can provide an alarm time more than 4 days in advance compared with the actual recording time. It is beneficial for wind farm staff to replace equipment in advance and improve the economic benefits of wind farm operation.
The traditional sea clutter simulation techniques encounter challenges in effectively balancing dynamic simulation, coupling effects, and construction cost management. To tackle these issues, we propose an experimenta...
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The traditional sea clutter simulation techniques encounter challenges in effectively balancing dynamic simulation, coupling effects, and construction cost management. To tackle these issues, we propose an experimental platform to simulate the sea clutter in real time using space-time-coding digital metasurfaces. Specifically, we use deep learning techniques to construct an encoding retrieval library with angle-insensitive characteristics. Combining the library with the desired clutter sequences generated by the zero memory nonlinearity approach, we can obtain the corresponding space-time-coding sequences for the simulation platform. To validate the proposed approach, we generate two correlated clutter signals following the Weibull and lognormal distributions under the illumination of monochromatic electromagnetic plane waves. Experimental results exhibit robust conformity with the theoretical values, demonstrating the dependability and stability of the proposed approach. These findings highlight the significant potential of our methods in various domains, including radar sensing and countermeasures.
Partially crystalline emulsions (PCEs) such as whipping cream and aerated emulsions can be stored in refrigerated or frozen conditions, but maintaining their stability at room temperature for an extended period is a s...
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Partially crystalline emulsions (PCEs) such as whipping cream and aerated emulsions can be stored in refrigerated or frozen conditions, but maintaining their stability at room temperature for an extended period is a significant challenge. Within the storage range of long shelf life, this study found that enriched diacylglycerol (DAG) oil-based PCEs have the ability to significantly improve the emulsion stability compared to triacylglycerol (TAG)-based PCEs. Subsequently, a multi-scale research approach was adopted, gradually revealing the underlying stability mechanisms. Studies have demonstrated that the interaction between the flexible casein and DAG in milk proteins predominantly happened at the interface of fat globules, heightening the spatial hindrance of the interface membrane to ensure the enduring stability of fat globules during storage. Moreover, the correlation between interfacial rheology and Q-CMD, molecular dynamics simulations has been confirmed from a microscopic and molecular level perspective, validating the mechanisms behind macroscopic performance patterns. Furthermore, Q-CMD and interfacial rheology demonstrated that the active hydroxyl groups of DAG and proteins can exist together to cooperatively control the strength of the interfacial membrane, thus laying the foundation for controlling the partial coalescence behavior of PCEs fat globules. This article elucidated the mechanism by which the interaction between casein and DAG enhances the stability of PCEs, providing a theoretical basis for the design of long shelf life PCEs.
Perfluorinated or polyfluorinated compounds(PFCs)continue entering to the environmental as individuals or mixtures,but their toxicological information remains largely ***,we investigated the toxic effects and ecologic...
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Perfluorinated or polyfluorinated compounds(PFCs)continue entering to the environmental as individuals or mixtures,but their toxicological information remains largely ***,we investigated the toxic effects and ecological risks of Perfluorooctane sulfonic acid(PFOS)and its substitutes on prokaryotes(Chlorella vulgaris)and eukaryotes(Microcystis aeruginosa).Based on the calculated EC50 values,the results showed that PFOS was significantly more toxic to both algae than its alternatives including Perfluorobutane sulfonic acid(PFBS)and 6:2 Fluoromodulated sulfonates(6:2 FTS),and the PFOS-PFBS mixture was more toxic to both algae than the other two PFC *** action mode of binary PFC mixtures on Chlorella vulgaris was mainly shown as antagonistic and on Microcystis aeruginosa as synergistic,by using Combination index(CI)model coupled with Monte Carlo *** mean risk quotient(RQ)value of three individual PFCs and their mixtures were all below the threshold of 10^(−1),but the risk of those binary mixtures were higher than that of PFCs individually because of their synergistic *** findings contribute to enhance the understanding of the toxicological information and ecological risks of emerging PFCs and provide a scientific basis for their pollution control.
Database watermarking technologies provide an effective solution to data security problems by embedding the watermark in the database to prove copyright or trace the source of data ***,when the watermarked database is...
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Database watermarking technologies provide an effective solution to data security problems by embedding the watermark in the database to prove copyright or trace the source of data ***,when the watermarked database is used for data mining model building,such as decision trees,it may cause a different mining result in comparison with the result from the original database caused by the distortion of watermark *** watermarking algorithms mainly consider the statistical distortion of data,such as the mean square error,but very few consider the effect of the watermark on database ***,in this paper,a consistency preserving database watermarking algorithm is proposed for decision ***,label classification statistics and label state transfer methods are proposed to adjust the watermarked data so that the model structure of the watermarked decision tree is the same as that of the original decision ***,the splitting values of the decision tree are adjusted according to the defined constraint ***,the adjusted database can obtain a decision tree consistent with the original decision *** experimental results demonstrated that the proposed algorithm does not corrupt the watermarks,and makes the watermarked decision tree consistent with the original decision tree with a small distortion.
This paper uses the minimization and weighted sum of battery capacity loss and energy consumption under driving cycles as objective functions to improve the economy of Electric Vehicles(EVs)with an hybrid energy stora...
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This paper uses the minimization and weighted sum of battery capacity loss and energy consumption under driving cycles as objective functions to improve the economy of Electric Vehicles(EVs)with an hybrid energy storage system composed of power batteries and ***,Dynamic programming(DP)is employed to determine the objective function values under different weight coefficients,the comprehensive cost consisting of battery aging and power consumption costs,and the relationship between the hybrid power *** also evaluate the real-time fuzzy Energy Management Strategy(EMS),fuzzy control strategies,and a strategy based on DP using the World Light vehicle Test Procedure(WLTP)driving cycle and a synthesis driving cycle derived from New European Driving Cycle(NEDC),WLTP,and Urban Dynamometer Driving Schedule(UDDS)as ***,the proposed strategy is compared with the fuzzy control strategy and the strategy based on *** with fuzzy energy management strategy(namely FZY-EMS),the proposed EMS reduces the battery capacity loss and system energy *** results demonstrate the effectiveness of the proposed EMS in improving EV economy.
Bloodstains are crucial pieces of physical evidences found at violent crime scenes, providing valuable information for reconstructing forensic cases. However, there is limited data on how bloodstain lipidomes change o...
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Bloodstains are crucial pieces of physical evidences found at violent crime scenes, providing valuable information for reconstructing forensic cases. However, there is limited data on how bloodstain lipidomes change over time after deposition. Hence, we deployed a high-throughput high-performance liquid chromatography-mass spectrometry (HPLC-MS) approach to construct lipidomic atlases of bloodstains, whole blood, plasma, and blood cells from 15 healthy adults. A time-course analysis was also performed on bloodstains deposited for up to 6 months at room temperature (similar to 25 degrees C). The molecular levels of 60 out of 400 detected lipid species differed dramatically between bloodstain and whole blood samples, with major disturbances observed in membrane glycerophospholipids. More than half of these lipids were prevalent in the cellular and plasmic fractions;approximately 27% and 10% of the identified lipids were uniquely derived from blood cells and plasma, respectively. Furthermore, a subset of 65 temporally dynamic lipid species arose across the 6-month room-temperature deposition period, with decreased triacylglycerols (TAGs) and increased lysophosphatidylcholines (LPCs) as representatives, accounting for approximately 8% of the total investigated lipids. The instability of lipids increased linearly with time, with the most variability observed in the first 10 days. This study sheds light on the impact of air-drying bloodstains on blood components at room temperature and provides a list of potential bloodstain lipid markers for determining the age of bloodstains.
This paper investigates a class of constrained distributed zeroth-order optimization(ZOO) problems over timevarying unbalanced graphs while ensuring privacy preservation among individual agents. Not taking into accoun...
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This paper investigates a class of constrained distributed zeroth-order optimization(ZOO) problems over timevarying unbalanced graphs while ensuring privacy preservation among individual agents. Not taking into account recent progress and addressing these concerns separately, there remains a lack of solutions offering theoretical guarantees for both privacy protection and constrained ZOO over time-varying unbalanced *** hereby propose a novel algorithm, termed the differential privacy(DP) distributed push-sum based zeroth-order constrained optimization algorithm(DP-ZOCOA). Operating over time-varying unbalanced graphs, DP-ZOCOA obviates the need for supplemental suboptimization problem computations, thereby reducing overhead in comparison to distributed primary-dual methods. DP-ZOCOA is specifically tailored to tackle constrained ZOO problems over time-varying unbalanced graphs,offering a guarantee of convergence to the optimal solution while robustly preserving privacy. Moreover, we provide rigorous proofs of convergence and privacy for DP-ZOCOA, underscoring its efficacy in attaining optimal convergence without constraints. To enhance its applicability, we incorporate DP-ZOCOA into the federated learning framework and formulate a decentralized zeroth-order constrained federated learning algorithm(ZOCOA-FL) to address challenges stemming from the timevarying imbalance of communication topology. Finally, the performance and effectiveness of the proposed algorithms are thoroughly evaluated through simulations on distributed least squares(DLS) and decentralized federated learning(DFL) tasks.
In this research, for the first time, we introduce a vapor-monitoring headspace strategy to establish a new methodology for determining the water absorbability of cellulose-derived materials. The method involves detec...
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In this research, for the first time, we introduce a vapor-monitoring headspace strategy to establish a new methodology for determining the water absorbability of cellulose-derived materials. The method involves detecting the water in the gas phase from various cellulose-derived materials after achieving the equilibrium state. By utilizing the headspace technique to monitor the change in water vapor pressure from bound water to free water, a change point indicating the water absorbability can be identified through fitting procedures. The study showed that the newly-established method possesses high precision (relative standard deviation <= 2.92%) and accuracy (relative differences <= 5.74%) for water absorbability analysis. The present method emerges as a facile and reliable tool for measuring water absorbability, and the introduction of the vapor-monitoring headspace strategy is anticipated to inspire the development of a new type of analytical method.
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