1,419 results
Search Results
2. Research on configuration design and operation effect evaluation for ultra high voltage (UHV) vertical insulator cleaning robot
- Author
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Yan, Yu, Jiang, Wei, Zhang, An, Li, Qiao Min, Li, Hong Jun, Chen, Wei, and Lei, YunFei
- Published
- 2020
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3. Calibration of a six-axis parallel manipulator based on BP neural network
- Author
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Zhang, Dianjin, Zhang, Guangyu, and Li, Longqiu
- Published
- 2019
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4. Prediction of Ultimate Bearing Capacity of Soil–Cement Mixed Pile Composite Foundation Using SA-IRMO-BPNN Model.
- Author
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Xi, Lin, Jin, Liangxing, Ji, Yujie, Liu, Pingting, and Wei, Junjie
- Subjects
METAHEURISTIC algorithms ,SIMULATED annealing ,GEOTECHNICAL engineering ,CIVIL engineering ,PREDICTION models - Abstract
The prediction of the ultimate bearing capacity (UBC) of composite foundations represents a critical application of test monitoring data within the field of intelligent geotechnical engineering. This paper introduces an effective combinational prediction algorithm, namely SA-IRMO-BP. By integrating the Improved Radial Movement Optimization (IRMO) algorithm with the simulated annealing (SA) algorithm, we develop a meta-heuristic optimization algorithm (SA-IRMO) to optimize the built-in weights and thresholds of backpropagation neural networks (BPNN). Leveraging this integrated prediction algorithm, we forecast the UBC of soil–cement mixed (SCM) pile composite foundations, yielding the following performance metrics: RMSE = 3.4626, MAE = 2.2712, R = 0.9978, VAF = 99.4339. These metrics substantiate the superior predictive performance of the proposed model. Furthermore, we utilize two distinct datasets to validate the generalizability of the prediction model presented herein, which carries significant implications for the safety and stability of civil engineering projects. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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5. Civil Aviation Passenger Traffic Forecasting: Application and Comparative Study of the Seasonal Autoregressive Integrated Moving Average Model and Backpropagation Neural Network.
- Author
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Gu, Weifan, Guo, Baohua, Zhang, Zhezhe, and Lu, He
- Abstract
With the rapid development of China's aviation industry, the accurate prediction of civil aviation passenger volume is crucial to the sustainable development of the industry. However, the current prediction of civil aviation passenger traffic has not yet reached the ideal accuracy, so it is particularly important to improve the accuracy of prediction. This paper explores and compares the effectiveness of the backpropagation (BP) neural network model and the SARIMA model in predicting civil aviation passenger traffic. Firstly, this study utilizes data from 2006 to 2019, applies these two models separately to forecast civil aviation passenger traffic in 2019, and combines the two models to forecast the same period. Through comparing the mean relative error (MRE), mean square error (MSE), and root mean square error (RMSE), the prediction accuracies of the two single models and the combined model are evaluated, and the best prediction method is determined. Subsequently, using the data from 2006 to 2019, the optimal method is applied to forecast the civil aviation passenger traffic from 2020 to 2023. Finally, this paper compares the epidemic's impact on civil aviation passenger traffic with the actual data. This paper improves the prediction accuracy of civil aviation passenger volume, and the research results have practical significance for understanding and evaluating the impact of the epidemic on the aviation industry. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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6. Dynamic trajectory-tracking control method of robotic transcranial magnetic stimulation with end-effector gravity compensation based on force sensors
- Author
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Lin, ZeCai, Xin, Wang, Yang, Jian, QingPei, Zhang, and ZongJie, Lu
- Published
- 2018
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7. Dynamic prediction of overhead transmission line ampacity based on the BP neural network using Bayesian optimization.
- Author
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Yong Sun, Yuanqi Liu, Bowen Wang, Yu Lu, Ruihua Fan, Xiaozhe Song, Yong Jiang, Xin She, Shengyao Shi, Kerui Ma, Guoqing Zhang, Xinyi Shen, Jiashen Teh, and Olatunji Lawal
- Subjects
ELECTRIC lines ,BAYESIAN analysis ,HEAT equation ,WEATHER ,LOSS control - Abstract
Traditionally, the ampacity of an overhead transmission line (OHTL) is a static value obtained based on adverse weather conditions, which constrains the transmission capacity. With the continuous growth of power system load, it is increasingly necessary to dynamically adjust the ampacity based on weather conditions. To this end, this paper models the heat balance relationship of the OHTL based on a BP neural network using Bayesian optimization (BO-BP). On this basis, an OHTL ampacity prediction method considering the model error is proposed. First, a two-stage current-stepping ampacity prediction model is established to obtain the initial ampacity prediction results. Then, the risk control strategy of ampacity prediction considering the model error is proposed to correct the ampacity based on the quartile of the model error to reduce the risk of the conductor overheating caused by the model error. Finally, a simulation is carried out based on the operation data of a 220-kV transmission line. The simulation results show that the accuracy of the BO-BP model is improved by more than 20% compared with the traditional heat balance equation. The proposed ampacity prediction method can improve the transmission capacity by more than 150% compared with the original static ampacity. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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8. Research on Neural Network Prediction Model of Whole Process Risk Management Based on Building Information Model.
- Author
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Huang, Shihong, Liang, Chengye, Liu, Jiao, and Wei, Xin-Jiang
- Subjects
BUILDING information modeling ,BACK propagation ,CONSTRUCTION projects ,INFORMATION networks ,CONSTRUCTION industry - Abstract
With the rapid development of China's construction industry and the acceleration of urbanization, large‐scale public building projects are becoming increasingly important in urban development, and the risk management problems of them should be pay more attention to. Based on the integration of back propagation (BP) neural network and building information model (BIM) technology, this paper carries out the research on risk management process of the whole life cycle of large public buildings and identifies the risk factors of large public buildings from the application dimension and the management dimension. The risk management evaluation index system is constructed and identified, and assessment, early warning, prevention, and control of risk management are applied and analyzed throughout the process. The international large public sports center project is used as a case study to establish a BIM model, while the BP neural network risk management model is used for prediction and calculation. The results of this study show that, first, the maximum deviation rate of the output indicators of the BP neural network risk model is 3.57% in the design period (B2) and the minimum deviation rate is 0.00% in the commissioning period (B4), which verifies the reliability of the training results of the model. Second, the best effect of risk management in the whole life cycle of the building is in the investment period (B1) and the highest risk is in the construction period (B3). Last, this paper constructs a new risk management framework to realise the risk management of the whole cycle of construction projects from design to operation, which helps to improve the management level and risk response ability of construction projects and ensure the smooth and sustainable development of the whole life cycle of construction. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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9. Orthogonal Matrix-Autoencoder-Based Encoding Method for Unordered Multi-Categorical Variables with Application to Neural Network Target Prediction Problems.
- Author
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Wang, Yiying, Li, Jinghua, Yang, Boxin, Song, Dening, and Zhou, Lei
- Subjects
ARTIFICIAL neural networks ,BAYESIAN analysis ,ELECTRONIC data processing ,PROBLEM solving ,ENCODING - Abstract
Neural network models, such as BP, LSTM, etc., support only numerical inputs, so data preprocessing needs to be carried out on the categorical variables to convert them into numerical data. For unordered multi-categorical variables, existing encoding methods may produce dimensional catastrophes and may also introduce additional order misrepresentation and distance bias in neural network computation. To solve the above problems, this paper proposes an unordered multi-categorical variable encoding method O-AE using orthogonal matrix for encoding and encoding representation learning and dimensionality reduction via an autoencoder. Bayesian optimization is used for hyperparameter optimization of the autoencoder. Finally, seven experiments were designed with the basic O-AE, Bayesian optimization of the hyperparameters of the autoencoder for O-AE, and other encoding methods to encode unordered multi-categorical variables in five datasets, and they were input into a BP neural network to carry out target prediction experiments. The results show that the experiments using O-AE and O-AE-b have better prediction results, proving that the method proposed in this paper is highly feasible and applicable and can be an optional method for the data processing of unordered multi-categorical variables. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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10. Study on the Identification of Opportunistic Behavior of Subway Project Construction Enterprises.
- Author
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Wen, Yanfang, Huang, Dinglei, and Cao, Zhi
- Subjects
OPPORTUNISM (Psychology) ,URBAN transportation ,CONSTRUCTION projects ,AT-risk behavior ,RAILROADS - Abstract
With the rapid development of urban rail transportation, people's demand for subways has gradually manifested itself. The inherent complex attributes of subway project construction determine that subway project construction has a relatively high risk, resulting in huge losses. This paper takes the opportunistic behavior of the subway project as the research object, proposes the opportunistic behavior identification process, and constructs the opportunistic behavior identification model based on the BP neural network. Firstly, through the collection and analysis of subway accident cases, the main forms of opportunistic behavior are summarized, and the primary characteristic indicators for opportunistic behavior recognition are extracted using cluster analysis. Secondly, a recognition model based on a BP neural network is designed. The number of neurons in the input layer, hidden layer, and output layer of the model is determined, and the recognition model is subsequently trained and tested to validate its feasibility. Finally, the constructed opportunistic behavior recognition model is applied to an actual subway construction project, revealing that the construction enterprise of the project in question exhibits a high level of opportunistic behavior risk. Overall, the research results of this paper have important theoretical significance and practical value for the management level of subway project construction enterprises under the new situation and the identification and governance of opportunistic behavior of subway project construction enterprises. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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11. An Improved InVEST Ecological Service Evaluation Model Based on BP Neural Network Optimization.
- Author
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Feng Wang, Wenlong Chen, and Lei Niu
- Subjects
ENVIRONMENTAL economics ,ARTIFICIAL neural networks ,ECOLOGICAL assessment ,COST control ,WATER pollution - Abstract
The land is the material basis for human survival, and the contradiction between people and land has become increasingly prominent. The land ecological problem has gradually become a hot spot of concern. It is imperative to make a scientific evaluation of the land ecological quality and propose reasonable and feasible improvement measures and recommendations. At present, domestic research on environmental cost and environmental cost degradation mostly focuses on theoretical discussion, and there are few applications and practical research on enterprise environmental cost management. Based on the principle of protecting the ecological environment, this paper creates an ecological service assessment model to assess the real economic cost of land use development projects. From small community projects to large-scale national projects, because environmental costs are difficult to estimate, this paper uses the recovery cost method and the preventive expenditure method to quantify environmental costs. The cost of environmental degradation mainly comes from water pollution and air pollution. This paper uses the pollution function method to quantify the cost of environmental degradation. The InVEST model is used to evaluate the value of ecosystem services, and the BP neural network method is used to optimize the ecosystem service model, and the sensitivity analysis of the data is used to feedback the impact of the project on ecosystem services. The ecosystem service model based on neural network optimization makes the accuracy of data measurement results reaching 99.7%, which makes the model having a good generalization. Taking a paper mill as an example, this paper evaluates environmental costs by resource consumption cost, environmental degradation value and environmental governance cost, and estimates environmental degradation costs by major environmental governance costs. Finally, the environmental cost and environmental degradation cost are integrated, and the ecosystem service model is established. The neural network model was established in the Matlab environment based on the InVEST model, and the model simulation results of the ecosystem service system were obtained. Compared with the InVEST results, the results of this paper have better authenticity and market utilization value. Although a paper mill was used as an example, the system was evaluated and the evaluation results were analysed. Compared with the actual situation, there is a certain reliability. However, due to the limited data, the number of verifications is insufficient for the system. It is hoped that more data can be verified later to ensure its reliability. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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12. An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver.
- Author
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Yiming Liang, Guangning Li, Min Xu, Junmin Zhao, Feng Hao, and Hongbo Shi
- Subjects
ARTIFICIAL neural networks ,INTELLIGENT control systems ,COMPUTER simulation ,PROJECTILES ,MANEUVER warfare - Abstract
In this paper, an intelligent control method applying on numerical virtual flight is proposed. The proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application prospect. Firstly, a numerical virtual flight simulation model based on overlapping dynamic mesh technology is constructed. In order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow, a numerical simulation of the basic finner projectile without control is carried out. The simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight simulation. Secondly, combined with the real-time control requirements of aerodynamic, attitude and displacement parameters of the projectile during the flight process, the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative) control strategy and the intelligent PID control strategy respectively. The intelligent PID controller based on BP(Back Propagation) neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight parameters. Compared with the traditional PID controller, the concerned control variable overshoot, rise time, transition time and steady state error and other performance indicators have been greatly improved, and the higher the learning efficiency or the inertia coefficient, the faster the system, the larger the overshoot, and the smaller the stability error. The intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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13. Prediction of Health Status of Small-Tailed Cold Sheep Based on Improved BP Neural Network.
- Author
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Fan, Wei, Wang, Haixia, Hou, Yun, Du, Hongwei, Zhang, Haiyang, Yang, Jing, Li, Tingxia, and Han, Ding
- Subjects
ARTIFICIAL neural networks ,PHYSIOLOGICAL effects of cold temperatures ,SHEEP ,TEST systems ,BODY temperature - Abstract
According to related research, different body temperatures, heart rates, and locomotor behaviors of small-tailed cold goats can represent the physical condition of the goats themselves and are used as direct evidence for evaluating the physical health status of small-tailed cold goats. In this paper, we designed and tested a system for predicting the health status of small-tailed cold sheep based on wearable information monitoring technology. To test the system, sheep wearable devices were worn on 36 small-tailed cold sheep of different ages and inconsistent health conditions at different time points from May to October. A SLBAS-BP neural network model for predicting the health condition of small-tailed cold sheep was established using the collected and processed data, which overcame the problem that the traditional gradient descent method in the BP neural network is prone to fall into local optimization leading to insufficient prediction ability. The correct prediction rates of the improved BP neural network for the four health conditions of healthy, sub-healthy, fever, and disease were 98.4%, 94.5%, 90.4%, and 98.7%, respectively, and the average correct prediction rate of the four conditions was 5.8% higher than that before the improvement, reaching 95.2%. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
14. Optimization Study of Steady-State Aerial-Towed Cable Circling Strategy Based on BP Neural Network Prediction.
- Author
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Feng, Luqi, Liu, Xueqiang, and Nio, Zi Feng
- Subjects
PARTICLE swarm optimization ,CABLES - Abstract
This paper presents models for UAV aerial-towed cables in free-end and fixed-end configurations, crucial for tasks like communication and aerial charging. By establishing a quasi steady-state model, computational results on cable shapes are obtained. To accelerate computations, a backpropagation (BP) neural network prediction model is trained, significantly reducing the computation time. An evaluation function has been developed that integrates both aircraft performance and cable shape considerations to evaluate circling parameters across various states. This function integrates techniques such as BP neural networks and particle swarm optimization (PSO) to refine parameters such as velocities and bank angles for both free-end and fixed-end cables. The results show that the BP neural network accurately predicts cable shapes, achieving a maximum error of 5% in towing force and verticality. Additionally, PSO efficiently optimizes circling parameters, thereby enhancing the effectiveness of the evaluation function in identifying optimal solutions. This approach significantly improves the efficiency of determining optimal circling parameters for UAV aerial-towed cables, thereby contributing to their operational efficacy. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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15. An improved genetic-back propagation network constructing strategy for high-precision state-of-charge estimation of complex-current-temperature-variation lithium-ion batteries.
- Author
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Zhan, Lihuan, Wang, Shunli, Hai, Nan, Ren, Pu, and Stroe, Daniel-Ioan
- Abstract
Environmental issues have driven the booming development of lithium-ion battery technology, and improving the accuracy of state-of-charge (SOC) measurements will play an important role in prolonging battery cycle life and improving safety. In this paper, an improved genetic-back propagation network construction strategy is built to stably and accurately estimate the SOC at different temperatures. The design of the established SOC neural network estimation model is optimized by using a genetic algorithm to initialize the weights and thresholds of the backpropagation (BP) neural network. Then, the above algorithms are validated using Dynamic Stress Test (DST) and Beijing Bus Dynamic Stress Test (BBDST) datasets. The experimental results show that the MAE and RMSE of the SOC estimation results based on the BBDST dataset are 0.0133, 0.0143 and 0.0058, 0.0082 under the conditions of − 5 °C and 35 °C. Therefore, the improved genetic-back propagation network construction algorithm has a more stable iterative process and higher estimation accuracy, which provides a new method for SOC performance estimation of lithium-ion batteries. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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16. PMT Fluorescence Signal Denoising Processing Based on Wavelet Transform and BP Neural Network.
- Author
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Liu, Jiehui, Zhang, Yunhan, Li, Jianshen, Zhao, Yadong, Guo, Jinxi, Yang, Lijie, and Zhao, Haichao
- Subjects
WAVELET transforms ,SIGNAL processing ,PHOTOELECTRICITY ,SULFUR dioxide ,FLUORESCENCE ,TRACE gases ,PHOTOMULTIPLIERS ,IMAGE denoising - Abstract
Featured Application: This study is aimed at the detection of sulfur dioxide concentration in the real environment. Due to the vast territory of China and the large temperature difference span between the north and the south, the current sulfur dioxide detection devices find it difficult to meet the requirements of portability, low-cost delivery, and temperature adaptability. A reliable real-time monitoring device and detection algorithm for sulfur dioxide concentration using PMT are proposed. Air is the environmental foundation for human life and production, and its composition changes are closely related to human activities. Sulfur dioxide (SO
2 ) is one of the main atmospheric pollutants, mainly derived from the combustion of fossil fuels. But SO2 is a trace gas in the atmosphere, and its concentration may be less than one part per billion (ppb). This paper is based on the principle of photoluminescence and uses a photomultiplier tube (PMT) as a photoelectric converter to develop a device for real-time detection of SO2 concentration in the atmosphere. This paper focuses on the impact of noise interference on weak electrical signals and uses wavelet transform to denoise the signals. At the same time, considering that the photoelectric system is susceptible to temperature changes, a multi parameter fitting model is constructed, and a BP neural network is used to further process the signal, separating the real data from the original data. Finally, a high-precision and wide-range trace level sulfur dioxide concentration detection device and algorithm were obtained. [ABSTRACT FROM AUTHOR]- Published
- 2024
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17. Design of Non-Intrusive Online Monitoring System for Traction Elevators.
- Author
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Li, Zhixing, Ning, Jiahui, and Li, Tianhao
- Subjects
ONLINE monitoring systems ,ELEVATORS ,AUTOMOBILE vibration ,PRESSURE sensors ,AIR pressure ,SIGNAL-to-noise ratio ,WHEATSTONE bridge - Abstract
With the increase in elevator usage, more and more elevator real-time monitoring equipment is being applied to the operation of elevators. Traditional elevator monitoring equipment adopts a multi-sensor decentralized installation and layout, and the monitoring accuracy is low, which directly affects the effective alarm of the monitoring system; however, existing online monitoring systems cannot quickly alarm for faults. Aiming to solve the above problems, an elevator online monitoring system based on narrow-band Internet of Things (NB-IoT) is designed. The system is highly integrated with an STM32 main control chip, a six-axis acceleration gyroscope sensor, and an air pressure sensor to realize the edge calculation of the monitoring system. At the same time, this paper eliminates the temperature drift of the pressure sensor by using a temperature compensation algorithm and inputs the extracted characteristic parameters into the BP neural network for training to eliminate the zero drift so as to obtain the real-time height data of the elevator. The six-axis acceleration gyroscope sensor is used to calculate the posture so as to avoid the problem that a three-axis acceleration sensor or a three-axis gyroscope sensor alone cannot obtain accurate posture data. In order to further improve the monitoring accuracy, the peak-to-peak value of the signal is calculated by using a 95% confidence interval algorithm to reduce the suppression of the high-frequency components of the signal by noise and ensure that the signal has a large signal-to-noise ratio so that the obtained elevator car posture and vibration operation data are more accurate. Finally, the effectiveness of the proposed method is verified by experiments. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. A BP Neural Network-Based Method for Evaluating the Quality of Creative Education in Minority Regions.
- Author
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Yang, Man, Huang, Haining, Li, Sijing, Luo, Weitai, Chen, Mengzhen, Li, Ling, and Yan, Wei
- Subjects
EDUCATIONAL quality ,INFORMATION technology ,BACK propagation ,LEARNING ,SCHOOL integration - Abstract
Ethnic minority resources are very rich and contain rich historical resources and culture. Under the impact of modern information technology, the development of minority resources and the inheritance of ethnic culture are facing many challenges, and the current school education is lagging behind in exploring the ecological resources of minority groups, which makes the integration of creative education and minority groups encounter a bottleneck. In response to this situation, we make full use of the platform of creative education to actively explore the traditional skills contained in the lives of ethnic minorities. In the evaluation of creative education, we should not only focus on the evaluation of students' works, but also on the improvement of students' knowledge of various creative tools, their ability to use comprehensive subject knowledge, hands-on ability, solution ability and creativity ability during the whole learning process. Based on this, this paper proposes a back propagation neural network (BPNN)-based quality evaluation method for creative education to evaluate the quality of creative education from multiple dimensions. Experiments and comparisons show that the BPNN-based evaluation method proposed in this paper can better evaluate the whole process of creative education and help the further development of creative education in minority regions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
19. Optimal Modification of Peak-Valley Period Under Multiple Time-of-Use Schemes Based on Dynamic Load Point Method Considering Reliability.
- Author
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Yang, Hejun, Gao, Yuan, Ma, Yinghao, and Zhang, Dabo
- Subjects
DYNAMIC loads ,RELIABILITY in engineering ,TEST systems ,POWER resources ,ELECTRIC power distribution grids ,BACK propagation - Abstract
Time-of-use (TOU) is an effective price-based demand response strategy. A reasonable design of TOU strategy can effectively reduce the peak-valley difference, and then produce a lot of benefits (such as delaying power grid investment, reducing interruption cost, and improving reliability). However, changing peak-valley period has a great influence on the peak-valley difference and power supply reliability of power system. Therefore, this paper aims to investigate the optimal modification of peak-valley period considering reliability loss under multiple TOU schemes. Firstly, this paper presents a clustering model and algorithm of optimal load curve based on a minimum error iteration method. Secondly, an optimal modification of peak-valley period based on a dynamic load point method is proposed, and the traditional peak-valley difference is replaced by the global peak-valley difference to calculate the objective function. Thirdly, this paper establishes a load–reliability relation fitting model based on the back propagation neural network. Finally, the effectiveness and correctness of the proposed method are investigated by the Roy Billinton test system and reliability test system. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
20. Study on the measurement and prediction of the ecological structure for water efficiency in China: from the perspective of “production-living-ecological” function
- Author
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Tang, Yan, Cheng, Yunpei, Gao, Shan, and Wang, Xinzhi
- Published
- 2024
- Full Text
- View/download PDF
21. Research on wear state identification and life prediction technology of ultrasonic straight-edge knife.
- Author
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Ji, Huawei, Yang, Fan, Wang, Zhibing, Hu, Xiaoping, Qi, Anqi, Lv, Bo, Wu, Xin, and Ni, Jing
- Subjects
ULTRASONICS ,ULTRASONIC cutting ,CUTTING force ,K-nearest neighbor classification ,KNIVES ,SERVICE life - Abstract
Ultrasonic cutting technology is widely used in the processing of Nomex honeycomb composites, but the identification of wear state and life prediction of ultrasonic straight-edge cutter are one of the problems to be solved urgently. In this paper, based on the tool wear mechanism, the multi-dimensional parameters of cutting force and cutting sound signal are extracted through experiments, the tool wear characteristics are established, and the tool wear stages are divided based on BP neural network and K-nearest neighbor cluster analysis, we established a tool wear recognition model with an accuracy rate of 92.3%. Further, a remaining life prediction model is established based on the HMM model, which can accurately predict the service life of the tool. The research on the wear state and remaining life of ultrasonic tools in this paper provides theoretical significance for the diagnosis of acoustic system faults and has important engineering value for reducing enterprise economic expenses and improving parts processing quality. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
22. Anti-Offset Multicoil Underwater Wireless Power Transfer Based on a BP Neural Network.
- Author
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Fu, You, Tang, Haodong, Luo, Jianan, and Peng, Zhouhua
- Subjects
WIRELESS power transmission ,SLIDING mode control ,BLOOD pressure testing machines ,AUTONOMOUS underwater vehicles ,OCEAN currents ,POWER resources ,ENERGY transfer - Abstract
Autonomous underwater vehicles (AUVs) are now widely used in both civilian and military applications; however, wireless charging underwater often faces difficulties such as disturbances from ocean currents and errors in device positioning, making proper alignment of the charging devices challenging. Misalignment between the primary and secondary coils can significantly impact the efficiency and power of the wireless charging system energy transfer. To address the issue of misalignment in wireless charging systems, this paper proposes a multiple transfer coil wireless power transfer (MTCWPT) system based on backpropagation (BP) neural network control combined with nonsingular terminal sliding mode control (NTSMC) to enhance further the system robustness and efficiency. To achieve WPT in the ocean, a coil shielding case structure was equipped. In displacement experiments, the proposed multi-transmitting coil system could achieve stable power transfer of 40 W and efficiency of over 78.5% within a displacement range of 8 cm. The system robustness was also validated. This paper presents a new AUV energy supply solution based on MTCWPT. The proposed MTCWPT system can significantly improve the navigation performance of AUVs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
23. A Hybrid Forecasting Model for Self-Similar Traffic in LEO Mega-Constellation Networks.
- Author
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Han, Chi, Xiong, Wei, and Yu, Ronghuan
- Subjects
COMPUTER network traffic ,GREY Wolf Optimizer algorithm ,HILBERT-Huang transform ,BACK propagation ,TRAFFIC estimation ,FORECASTING ,OPTIMIZATION algorithms - Abstract
Mega-constellation network traffic forecasting provides key information for routing and resource allocation, which is of great significance to the performance of satellite networks. However, due to the self-similarity and long-range dependence (LRD) of mega-constellation network traffic, traditional linear/non-linear forecasting models cannot achieve sufficient forecasting accuracy. In order to resolve this problem, a mega-constellation network traffic forecasting model based on EMD (empirical mode decomposition)-ARIMA (autoregressive integrated moving average) and IGWO (improved grey wolf optimizer) optimized BPNN (back-propagation neural network) is proposed in this paper, which makes comprehensive utilization of linear model ARIMA, non-linear model BPNN and optimization algorithm IGWO. With the enhancement of the global optimization capability of a BPNN, the proposed hybrid model can fully realize the potential of mining linear and non-linear laws of mega-constellation network traffic, hence improving the forecasting accuracy. This paper utilizes an ON/OFF model to generate historical self-similar traffic to forecast. RMSE (root mean square error), MAE (mean absolute error), R-square and MAPE (mean absolute percentage error) are adopted as evaluation indexes for the forecasting effect. Comprehensive experimental results show that the proposed method outperforms traditional constellation network traffic forecasting schemes, with several improvements in forecasting accuracy and efficiency. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. Big Data based approach to Network Security and intelligence.
- Author
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Alquaifil, Mubarak, Mishra, Shailendra, and AlShehri, Mohammed
- Subjects
COMPUTER network security ,BIG data ,BACK propagation ,INTERNET security ,SITUATIONAL awareness - Abstract
Big data analysis technologies and machine learning techniques are essential for examining and forecasting the state of network security as global concerns about cyber security grow. Models for monitoring network security have a number of challenges, including resource consumption, inaccuracies, low processing efficiency, and incompatibility with real-time and large-scale scenarios. This paper proposes a novel approach to Network Security Situation Awareness (NS-SA) using Big Data (BD) analytics and machine learning. The proposed approach addresses the limitations of existing NS-SA models by leveraging data purification and simplification techniques, and by employing an updated back propagation (BP) neural network to construct an NS BD analysis model. The paper provides a comprehensive explanation of the model's structure and outlines the relevant model techniques. Extensive testing has been conducted to ensure the model's accuracy and applicability in understanding NS scenarios. This study focuses on MATLAB and Python-based implementation of a neural network for network security using a big data approach. The results demonstrate the potential and value of the proposed model in accurately assessing and forecasting NS conditions. The proposed approach has several advantages over existing NS-SA models. It is more efficient in terms of resource usage, it is more accurate in its analysis of network data, It is more applicable in real-time and large-scale scenarios and it is more robust to noise and heterogeneity in network data. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
25. Research on Positioning Error Compensation of Rock Drilling Manipulator Based on ISBOA-BP Neural Network.
- Author
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Xu, Qiaoyu, Ju, Wenhao, Lin, Yansong, and Zhang, Tianle
- Subjects
OPTIMIZATION algorithms ,BACK propagation ,BIRD populations ,POINT set theory ,REQUIREMENTS engineering - Abstract
In order to solve the problem of the low end positioning accuracy of large hydraulic rock drilling robotic arms due to machining error and the working environment, this paper proposes an end positioning error compensation method based on an Improved Secretary Bird Optimization Algorithm (ISBOA) optimized Back Propagation (BP) neural network. Firstly, the good point set strategy is used to initialize the secretary bird population position to make the initial population distribution more uniform and accelerate the convergence speed of the algorithm. Then, the ISBOA is used to optimize the initial weights and biases of the BP neural network, which effectively overcomes the defect of the BP neural network falling into a local optimum. Finally, by establishing the mapping relationship between the joint value of the robot arm and the end positioning error, the error compensation is realized to improve the positioning accuracy of the rock drilling robot arm. The experimental results show that the average positioning error of the rock drilling robotic arm is reduced from 187.972 mm to 28.317 mm, and the positioning accuracy is improved by 84.94%, which meets the engineering requirements. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
26. Seismic Prediction Method of Shale Reservoir Brittleness Index Based on the BP Neural Network for Improving Shale Gas Extraction Efficiency.
- Author
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Zhang, Xuejuan, She, Haiyan, Zhang, Lei, Li, Ruolin, Feng, Jiayang, Liu, Ruhao, and Wang, Xinrui
- Subjects
POISSON'S ratio ,ARTIFICIAL neural networks ,MODULUS of rigidity ,YOUNG'S modulus ,OIL shales - Abstract
The current seismic prediction methods of the shale brittleness index are all based on the pre-stack seismic inversion of elastic parameters, and the elastic parameters are transformed by Rickman and other simple linear mathematical relationship formulas. In order to address the low accuracy of the seismic prediction results for the brittleness index, this study proposes a method for predicting the brittleness index of shale reservoirs based on an error backpropagation neural network (BP neural network). The continuous static rock elastic parameters were calculated by fitting the triaxial test data with well logging data, and the static elastic parameters with good correlation with the brittleness index of shale minerals were selected as the sample data of the BP neural network model. A dataset of 1970 data points, characterized by Young's modulus, Poisson's ratio, shear modulus, and the mineral brittleness index, was constructed. A total of 367 sets of data points from well Z4 were randomly retained as model validation data, and 1603 sets of data points from the other three wells were divided into model training data and test data at a ratio of 7:3. The calculation accuracy of the model with different numbers of nodes was analyzed and the key parameters of the BP neural network structure such as the number of input layers, the number of output layers, the number of hidden layers, and the number of neurons were determined. The gradient descent method was used to determine the weight and bias of the model parameters with the smallest error, the BP neural network model was trained, and the stability of the brittleness index prediction model of the BP neural network was verified by posterior data. After obtaining Young's modulus, Poisson's ratio, and shear modulus through pre-stack seismic inversion, the BP neural network model established in this study was used to predict the brittleness index distribution of the target layer in the study area. Compared with the conventional Rickman method, the prediction coincidence rate is 69.16%, and the prediction coincidence rate between the prediction results and the real value is 95.79%, which is 26.63% higher. The BP neural network method proposed in this paper provides a reliable new method for seismic prediction of the shale reservoir brittleness index, which has important practical significance for clarifying the shale gas development scheme and improving shale gas exploitation efficiency. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Study on the Prediction of Launcher Efficiency of Electromagnetic Launcher Based on Particle Swarm Optimization-Improved BP Neural Network.
- Author
-
Xiao, Nan, Li, Jun, and Yan, Ping
- Subjects
ELECTROMAGNETIC launchers ,KINETIC energy ,ELECTRICAL energy ,ARMATURES ,PARTICLE swarm optimization - Abstract
Launcher efficiency is an important index for evaluating the performance of the electromagnetic launcher, and it reflects the ability of the launcher to convert input electrical energy into kinetic energy of the armature. In this paper, the launcher efficiency is taken as the objective function of bore parameter optimization, and particle swarm optimization is used to optimize the initial parameters of the BP neural network to improve the accuracy of the neural network in predicting launcher efficiency. The results show the following: (1) The predicted efficiency of the launcher shows the same trend as the experimental results. When the ratio of rail separation and rail height is greater than 1.75, the rate of change in the launcher efficiency curve decreases as the rail separation increases. (2) The weight of the influence of each parameter on the launcher efficiency follows the following law: convex arc height > rail separation > rail height > rail thickness. (3) The mean absolute error of the BP neural network prediction is 0.70%; after optimization by PSO, the mean absolute error is reduced to 0.28% and the mean relative accuracy is improved from 0.9774 to 0.9910, which indicates the feasibility of the PSO-BP neural network for the prediction of the launcher efficiency of an electromagnetic launcher. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. Low Stress Level and Low Stress Amplitude Fatigue Loading Simulation of Concrete Components Containing Cold Joints under Fatigue Loading.
- Author
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Fu, He-Lin, Deng, Huang-Shi, Wu, Yi-Min, Zhao, Yi-Bo, and Xie, Cheng-Da
- Subjects
FATIGUE cracks ,CONCRETE fatigue ,FATIGUE life ,AERODYNAMIC load ,BACK propagation - Abstract
Concrete linings containing cold joint defects may crack or detach under the aerodynamic fatigue loading generated by high-speed train operation, which posing a serious threat to the normal operation of high-speed trains. However, there is currently no simulation method specifically for fatigue damage of concrete linings containing cold joints. Based on the Roe-Siegmund cycle cohesive force model, a cohesive force fatigue damage elements were developed. A large dataset was constructed through numerical simulation software to build a BP neural network for back-calculated parameter of cohesive force fatigue damage elements. By combining experimental data, fatigue damage parameters corresponding to different pouring interval cold joints were back-calculated. These back-calculated parameters were then incorporated into the numerical model to compare simulation results with experimental results to validate the applicability of cohesive force fatigue damage elements and back propagation neural networks (BP neural network). The research results show that the difference between the fatigue life and fracture process calculated by numerical simulation and experimental data is small, verifying the applicability of the method proposed in this paper. The pouring interval directly affects the initial strength of the cold joint interface and the starting conditions of fatigue damage. The possibility of fatigue damage and fracture of concrete components containing cold joints increases with the increase of pouring interval, while the variability of fatigue life decreases with the increase of pouring interval. Interface strength and thickness are the main factors affecting the possibility of fatigue damage occurrence and the variability of fatigue life. The research results can be used to analyze the damage and cracking status of concrete linings containing cold joints under aerodynamic fatigue loading. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. Linear Model Predictive Control and Back-Propagation Controller for Single-Point Magnetic Levitation with Different Gap Levitation and Back-Propagation Offline Iteration.
- Author
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Liu, Ziyu and Dou, Fengshan
- Subjects
ARTIFICIAL neural networks ,MAGNETIC suspension ,MOTOR vehicle springs & suspension ,LEVITATION ,VEHICLE models - Abstract
Magnetic suspension balance systems (MSBSs) need to allow vehicle models to levitate stably in different attitudes, so it is difficult to ensure the stable performance of the system under different levitation gaps using a controller designed with single balance point linearization. In this paper, a levitation controller based on linear model predictive control and a back-propagation neural network (LMPC-BP) is proposed and simulated for single-point magnetic levitation. The deviation of the BP network is observed and compensated by an expansion state observer (ESO). The iterative BP neural network model is further updated using current data and feedback data from the ESO, and then the performance of the LMPC-BP controller is evaluated before and after the update. The simulation results show that the LMPC-BP controller can achieve stable levitation at different gaps of the single-point magnetic levitation system. With further updating and iteration of the BP network, the controller anti-jamming performance is improved. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. Research on Predicting the Mechanical Characteristics of Deep-Sea Mining Transportation Pipelines.
- Author
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Hu, Qiong, Qin, Yu, Zhu, Jingyan, Zheng, Meiling, Huang, Junqiang, and Ou, Yujia
- Subjects
PIPELINE transportation ,MINES & mineral resources ,DYNAMIC mechanical analysis ,BENDING moment ,PREDICTION models - Abstract
Deep-sea mining, as a critical direction for the future development of mineral resources, places significant importance on the mechanical characteristics of its transportation pipelines for the safety and efficiency of the entire mining system. This paper establishes a simulation model of the deep-sea mining system based on oceanic environmental loads and the mechanical theory of deep-sea mining transportation pipelines. Through a static analysis, the effective tension along the pipeline length, the maximum values of bending moment, and the minimum values of bending radius are determined as critical points for the dynamic analysis of pipeline mechanical characteristic monitoring. A dynamic simulation analysis of the pipeline's mechanical characteristics was conducted, and simulation sensor data were obtained as inputs for the prediction model construction. A prediction model of pipeline mechanical characteristics based on the BP neural network was constructed, with the model's prediction correlation coefficients all exceeding 0.95, enabling an accurate prediction of pipeline state parameters. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Fault Diagnosis of Power Electronic Circuits Based on Improved Particle Swarm Optimization Algorithm Neural Network.
- Author
-
Zuming Xiao, Zhan Guo, and Balyan, Vipin
- Subjects
FAULT diagnosis ,ELECTRONIC circuits ,PARTICLE swarm optimization ,NEURAL circuitry ,HYPERBOLIC functions - Abstract
In the rapid development of high and new technology, the intelligence and integration of modern equipment are constantly improving. Power electronics technology is one of the indispensable key technologies in any high and new technology. In this paper, a power electronics circuit fault diagnosis based on improved particle swarm optimization neural network is proposed, the algorithm design of particle swarm optimization algorithm neural network is introduced, and the improved PS0 algorithm, standard PS0 algorithm, and BP algorithm optimized neural network are applied to the fault diagnosis classification system of rectifier circuits. The results show that the parameters of the basic (particle swarm optimization) algorithm are as follows: the parameter value of the basic PSO algorithm is the number of particles is 30, W decreases from 0.9 to 0.4 linearly with the increase of iterations, and the number of iterations is 300. The BP algorithm uses the traingdx training function. The transfer functions of the hidden layer and the output layer are hyperbolic tangent sigmoid and Purelin function, respectively. The target error e = 0.01. The superiority and effectiveness of the neural network diagnosis model of the improved PS0 algorithm are shown in this paper. This method can solve the fault diagnosis problem of the double-bridge parallel rectifier circuit. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
32. Study on the Maximum Level of Disposable Plastic Product Waste.
- Author
-
Hong, Yizhao
- Abstract
Plastic is a widely used material in daily life that has brought huge social benefits to society with the advantages of low-cost manufacturing and mildness. However, due to their high resistance to degradation and diversity of chemical components, plastics pose a great threat to human health and the living environment. Aiming to address the problem that there is a lot of plastic waste and its impact on the environment, this paper puts forward an effective plan to reduce plastic waste and tests the relevant models. First, based on the pollution index data of plastic waste, it uses the Analytic Hierarchy Process and the entropy weight model to determine the evaluation index weight of plastic waste pollution impact and judge the environmental damage ability and environmental recovery ability. Secondly, in order to measure the level of environmental safety, it establishes an evaluation index system and uses the gray correlation method to determine the weight value of the evaluation index and calculate the environmental safety scores of each country. Thirdly, according to the second index system, it selects the relevant data from 10 countries, establishes a BP neural network model, and calculates the level of security and the intensity of responsibility. Finally, based on the results of the model and the global goal of achieving the minimum level of plastic waste, it offers a memorandum with a schedule and discusses the measures needed to achieve this goal and the factors to be considered. Overall, compared with the existing research, this paper presents a different approach to the assessment and measurement of the use of the environment and its capacity for pollution, combining multi-disciplinary influencing factors. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
33. TentISSA-BPNN: a novel evaluation model for cloud service providers for petroleum enterprises
- Author
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Hou, Ke, Sun, Jianping, Guo, Mingcheng, Pang, Ming, and Wang, Na
- Published
- 2024
- Full Text
- View/download PDF
34. Temperature Compensation of Laser Methane Sensor Based on a Large-Scale Dataset and the ISSA-BP Neural Network.
- Author
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Yin, Songfeng, Zou, Xiang, Cheng, Yue, and Liu, Yunlong
- Subjects
LASER based sensors ,TEMPERATURE sensors ,LEVY processes ,SEARCH algorithms ,GLOBAL optimization ,TEMPERATURE - Abstract
We aimed to improve the detection accuracy of laser methane sensors in expansive temperature application environments. In this paper, a large-scale dataset of the measured concentration of the sensor at different temperatures is established, and a temperature compensation model based on the ISSA-BP neural network is proposed. On the data side, a large-scale dataset of 15,810 sets of laser methane sensors with different temperatures and concentrations was established, and an Improved Isolation Forest algorithm was used to clean the large-scale data and remove the outliers in the dataset. On the modeling framework, a temperature compensation model based on the ISSA-BP neural network is proposed. The quasi-reflective learning, chameleon swarm algorithm, Lévy flight, and artificial rabbits optimization are utilized to improve the initialization of the sparrow population, explorer position, anti-predator position, and position of individual sparrows in each generation, respectively, to improve the global optimization seeking ability of the standard sparrow search algorithm. The ISSA-BP temperature compensation model far outperforms the four models, SVM, RF, BP, and PSO-BP, in model evaluation metrics such as MAE, MAPE, RMSE, and R-square for both the training and test sets. The results show that the algorithm in this paper can significantly improve the detection accuracy of the laser methane sensor under the wide temperature application environment. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Optimizing Back-Propagation Neural Network to Retrieve Sea Surface Temperature Based on Improved Sparrow Search Algorithm.
- Author
-
Ji, Changming and Ding, Haiyong
- Subjects
OCEAN temperature ,MACHINE learning ,OPTIMIZATION algorithms ,BRIGHTNESS temperature ,SEARCH algorithms ,CLOUDINESS - Abstract
Sea surface temperature (SST) constitutes a pivotal physical parameter in the investigation of atmospheric, oceanic, and air–sea exchange processes. The retrieval of SST through satellite passive microwave (PMW) technology effectively mitigates the interference posed by cloud cover, addressing a longstanding challenge. Nevertheless, conventional functional representations often fall short in capturing the intricate interplay of factors influencing SST. Leveraging neural networks (NNs), known for their adeptness in tackling nonlinear and intricate problems, holds great promise in SST retrieval. Nonetheless, NNs exhibit a high sensitivity to initial weights and thresholds, rendering them susceptible to local optimization issues. In this study, we present a novel machine learning (ML) approach for SST retrieval using PMW measurements, drawing from the Sparrow Search Algorithm (SSA) and Back-Propagation neural network (BPNN) methodologies. The core premise involves the optimization of the BP neural network's initial weights and thresholds through an enhanced SSA algorithm employing various optimization strategies. This optimization aims to provide superior parameters for the training of the BP neural network. Employing AMSR2 brightness temperature data, sea surface wind speed data, and buoy SST measurements, we construct the ISSA-BP model for sea surface temperature retrieval. The validation of the ISSA-BP model against the test data is conducted and compared against the multiple linear regression (MLR) model, an unoptimized BP model, and an unimproved SSA-BP model. The results manifest an impressive R-squared (R
2 ) value of 0.9918 and a root-mean-square error (RMSE) of 0.8268 °C for the ISSA-BP model, attesting to its superior accuracy. Furthermore, the ISSA-BP model was applied to retrieve global sea surface temperatures on 15 July 2022, yielding an R2 of 0.9926 and an RMSE of 0.7673 °C for the OISST product on the same day, underscoring its excellent concordance. The results indicate that SST can be efficiently and accurately retrieved using the model proposed in this paper, based on satellite PMW measurements. This finding underscores the potential of employing machine learning algorithms for SST retrieval and offers a valuable reference for future studies focusing on the retrieval of other sea surface parameters. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
36. An Optimized Chinese Filtering Model Using Value Scale Extended Text Vector.
- Author
-
Siyu Lu, Ligao Cai, Zhixin Liu, Shan Liu, Bo Yang, Lirong Yin, Mingzhe Liu, and Wenfeng Zheng
- Subjects
ARTIFICIAL neural networks ,WORD frequency ,INFORMATION retrieval ,WEBSITES ,DATA analysis - Abstract
With the development of Internet technology, the explosive growth of Internet information presentation has led to difficulty in filtering effective information. Finding a model with high accuracy for text classification has become a critical problem to be solved by text filtering, especially for Chinese texts. This paper selected the manually calibrated Douban movie website comment data for research. First, a text filtering model based on the BP neural network has been built; Second, based on the Term Frequency-Inverse Document Frequency (TF-IDF) vector spacemodel and the doc2vec method, the text word frequency vector and the text semantic vector were obtained respectively, and the text word frequency vector was linearly reduced by the Principal Component Analysis (PCA)method. Third, the text word frequency vector after dimensionality reduction and the text semantic vector were combined, add the text value degree, and the text synthesis vector was constructed. Experiments show that the model combined with text word frequency vector degree after dimensionality reduction, text semantic vector, and text value has reached the highest accuracy of 84.67%. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
37. PSO-BP-Based Morphology Prediction Method for DED Remanufactured Deposited Layers.
- Author
-
Wang, Zisheng, Jiang, Xingyu, Song, Boxue, Yang, Guozhe, Liu, Weijun, Liu, Tongming, Ni, Zhijia, and Zhang, Ren
- Abstract
Directed energy deposition is a typical laser remanufacturing technology, which can effectively repair failed parts and extend their service life, and has been widely used in aerospace, metallurgy, energy and other high-end equipment key parts remanufacturing. However, the repair quality and performance of the repaired parts have been limited by the morphological and quality control problems of the process because of the formation mechanism and process of the deposition. The main reason is that the coupling of multiple process parameters makes the deposited layer morphology and surface properties difficult to be accurately predicted, which makes it difficult to regulate the process. Thus, the deposited layer forming mechanism and morphological properties of directed energy deposition were systematically analyzed, the height and width of multilayer deposition layers were taken as prediction targets, and a PSO-BP-based model for predicting the morphology of directed energy deposited layers was settled. The weights and thresholds of Back Propagation (BP) neural networks were optimized using a Particle Swarm Optimization (PSO) algorithm, the predicted values of deposited layer morphology for different process parameters were obtained, and the problem of low accuracy of deposited layer morphology prediction due to slow convergence and poor uniformity of the solution set of traditional optimization models was addressed. Remanufacturing experiments were conducted, and the experimental results showed that the deposited layer morphology prediction model proposed in this paper has a high prediction accuracy, with an average prediction error of 1.329% for the layer height and 0.442% for the layer width. The research of the paper provided an effective way to control the morphology and properties of the directed energy deposition process. A valuable contribution is made to the field of laser remanufacturing technology, and significant implications are held for various industries such as aerospace, metallurgy, and energy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. Prediction of Recrystallization Structure of 2A12 Aluminum Alloy Pipe Extrusion Process Based on BP Neural Network.
- Author
-
Jiang, Haishun, Wu, Rendong, Yuan, Chaolong, Jiao, Wei, Chen, Lingling, and Zhou, Xingyou
- Subjects
EXTRUSION process ,ALUMINUM alloys ,ALUMINUM construction ,RECRYSTALLIZATION (Metallurgy) ,BACK propagation ,HYDROSTATIC extrusion - Abstract
2A12 aluminum alloy is a high-strength aerospace alloy. During its extrusion process, the extrusion process parameters have a great impact on the microstructure evolution of the extruded products. There are three extrusion process parameters controlled in the actual project, which are the initial temperature of billet, the initial temperature of die and the extrusion speed. Combined with a back propagation (BP) neural network and finite element method (FEM) simulation, based on the constitutive equation and recrystallization evolution process of 2A12 aluminum alloy, this paper establishes a prediction model for the grain size of extruded pipe by these three extrusion process parameters. This paper used a 35MN extruding machine for a production verification of 2A12 pipe. The results show that the predicted grain size is 3% smaller than the actual size. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. Research on bearing fault diagnosis based on improved genetic algorithm and BP neural network.
- Author
-
Chen, Zenghua, Zhu, Lingjian, Lu, He, Chen, Shichao, Zhu, Fenghua, Liu, Sheng, Han, Yunjun, and Xiong, Gang
- Subjects
FAULT diagnosis ,ROLLER bearings ,STATE universities & colleges ,HILBERT-Huang transform - Abstract
Health monitoring and fault diagnosis of rolling bearings are crucial for the continuous and effective operation of mechanical equipment. In order to improve the accuracy of BP neural network in fault diagnosis of rolling bearings, a feature model is established from the vibration signals of rolling bearings, and an improved genetic algorithm is used to optimize the initial weights, biases, and hyperparameters of the BP neural network. This overcomes the shortcomings of BP neural network, such as being prone to local minima, slow convergence speed, and sample dependence. The improved genetic algorithm fully considers the degree of concentration and dispersion of population fitness in genetic algorithms, and adaptively adjusts the crossover and mutation probabilities of genetic algorithms in a non-linear manner. At the same time, in order to accelerate the optimization efficiency of the selection operator, the elite retention strategy is combined with the hierarchical proportional selection operation. Using the rolling bearing dataset from Case Western Reserve University in the United States as experimental data, the proposed algorithm was used for simulation and prediction. The experimental results show that compared with the other seven models, the proposed IGA-BPNN exhibit superior performance in both convergence speed and predictive performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. The Risk Analysis of Digital Inclusive Financial Platform Using Deep Learning Approach.
- Author
-
WEI SHI, SI-QI LONG, and YUE LI
- Subjects
FINANCIAL inclusion ,RISK assessment ,DEEP learning ,CREDIT risk management ,FINANCIAL risk ,RISK management in business - Abstract
This paper intends to investigate the risk management of inclusive digital financial platforms. First, it explains the idea of smart cities, their function, and inclusive financial risk control technologies based on big data. The varieties of digital inclusive financial platforms and their risk profiles are next examined. The Back Propagation (BP) neural network is used to build a BP-KMV model based on the KMV model. Finally, utilizing M Company as a case study, this paper uses the BP-KMV model to examine the credit risk and risk management of unlisted enterprises on the digital inclusive financial platform. The results show that of the four unlisted companies, L Company has the greatest default rate (7.35%), while J Company has the lowest default rate (4.82%). The highest research and development (R&D) spending rate is 14.1% for J company, while the highest patent ownership rate is 43.09% for L company. The data demonstrates a negative correlation between the percentage of R&D expenditures and the default rate of unlisted enterprises. In other words, a larger default risk is associated with lower R&D expense rates. Additionally, there is a correlation between patent ownership and default rates that is positive, suggesting that higher patent ownership rates are linked to higher default rates. Additionally, the risk management technologies of M business can complement one another. The theoretical research of comprehensive digital inclusive finance risk control can be enriched by the risk analysis of digital inclusive financial platforms utilizing the BP-KMV model in the context of smart cities. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. APPLICATION OF ANN IN TOURISM BUSINESS DEVELOPMENT FOR DEMAND FORECASTING AND MANAGEMENT OF TOURISM HEADCOUNT.
- Author
-
HONGYING ZHANG and LINGYUN JIANG
- Subjects
DEMAND forecasting ,TOURISM management ,BUSINESS development ,PARTICLE swarm optimization ,TOURISM ,PREDICTION models - Abstract
With the rapid development of tourism, it is imperative to forecast tourism demand to maintain the long-term stable development of the tourism industry and make good planning for future tourism enterprises. The study uses the classical model of artificial neural network-BP neural network for tourism number demand prediction, given the problems of traditional BP neural networks, such as prematurity and poor convergence speed, this paper studies the iterative optimization of the algorithm of particle swarm fusion immune mechanism and finds out the optimal network parameters, to build an IAPSO-BP tourism demand prediction model. Tourist amounts from 2007 to 2017 in certain area-related data samples, the training model of iterative speed and fitting effect, and the rolling forecasting method will be used to predict the 2018-2022 years of travel. It can be seen from the convergence curve that the convergence speed of parameter optimization of the IAPSO algorithm is the fastest; the improved IAPSO-BP network has the best training fitting effect, with a relative average error of 2.03% and an absolute average error of 4.37%, which is better than other forecasting methods. The IAPSO-BP prediction model has higher accuracy and better performance, which can provide an effective basis for the development planning of tourism enterprises and has higher practical application value. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
42. A Creep Model of Steel Slag–Asphalt Mixture Based on Neural Networks.
- Author
-
Deng, Bei, Zeng, Guowei, and Ge, Rui
- Subjects
CREEP (Materials) ,STRAINS & stresses (Mechanics) ,STEEL ,BACK propagation ,ARTIFICIAL intelligence ,SLAG - Abstract
To characterize the complex creep behavior of steel slag–asphalt mixture influenced by both stress and temperature, predictive models employing Back Propagation (BP) and Long Short-Term Memory (LSTM) neural networks are described and compared in this paper. Multiple stress repeated creep recovery tests on AC-13 grade steel slag–asphalt mix samples were conducted at different temperatures. The experimental results were processed into a group of independent creep recovery test results, then divided into training and testing datasets. The K-fold cross-validation was applied to the training datasets to fine-tune the hyperparameters of the neural networks effectively. Compared with the experimental curves, both the effects of BP and LSTM models were investigated, and the broad applicability of the models was proven. The performance of the trained LSTM model was observed by a 95% confidence interval around the fit errors, thereby the creep strain intervals for the testing dataset were obtained. The results suggest that the LSTM model had enhanced prediction compared the BP model for creep deformation trends of steel slag–asphalt mixture at various temperatures. Due to the potent generalization strength of artificial intelligence technology, the LSTM model can be further expanded for forecasting road rutting deformations. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. 黄土土壤水分运动参数预测模型研究.
- Author
-
秦文静 and 樊贵盛
- Abstract
Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
44. Research on the Three-Level Integrated Environmental Evaluation Model for Multi-Greenhouse Potatoes.
- Author
-
Liu, Shize, Zhong, Tao, Zhang, Huan, Zhang, Jian, Pan, Zhiguo, and Yang, Ranbing
- Subjects
REMOTE control ,PHOTOMETRY ,LARGE deviations (Mathematics) ,LIGHT intensity ,ATMOSPHERIC temperature - Abstract
Aiming at the problems of large error and redundancy in the multi-node data acquisition of multi-greenhouse photo growth environmental information, a three-level fusion algorithm based on adaptive weighting, an LMBP network, and an improved D-S theory is proposed. The box-and-line graph method recognizes the original data and then replaces it based on the mean value method; the air temperature, humidity, and light intensity measurements are unbiased estimations of the true value to be estimated, so the first level of fusion chooses the adaptive weighted average algorithm to find the optimal weights of each sensor under the condition of minimizing the total mean-square error and obtains the optimal estimation of the weights of the homogeneous sensors of a greenhouse. The Levenberg–Marquardt algorithm was chosen for the second level of fusion to optimize the weight modification of the BP neural network, i.e., the LMBP network, and the three environmental factors corresponding to "suitable", "uncertain" and "unsuitable" potato growth environments were trained for the three environmental factors in the reproductive periods. The output of the hidden layer was converted into probability by the Softmax function. The third level is based on the global fusion of evidence theory (also known as D-S theory), and the network output is used as evidence to obtain a consistent description of the multi-greenhouse potato cultivation environment and the overall scheduling of farming activities, which better solves the problem of the difficulty in obtaining basic probability assignments in the evidence theory; in the case of a conflict between the evidence, the BPA of the conflicting evidence is reallocated, i.e., the D-S theory is improved. Example validation shows that the total mean square error of the adaptive weighted fusion value is smaller than the variance of each sensor estimation, and sensors with lower variance are assigned lower weights, which makes the fusion result not have a large deviation due to the failure of individual sensors; when the fusion result of a greenhouse feature level is "unsuitable", the fusion result of each data level is considered comprehensively, and the remote control agency makes a decision, which makes full use of the complementary nature of multi-sensor information resources and solves the problem of fusion of multi-source environmental information and the problem of combining conflicting environmental evaluation factors. Compared with the traditional D-S theory, the improved D-S theory reduces the probability of the "uncertainty" index in the fusion result again. The three-level fusion algorithm in this paper does not sacrifice data accuracy and greatly reduces the noise and redundancy of the original data, laying a foundation for big data analysis. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. 基于余弦相似度和 TSO-BP 的短期光伏预测方法.
- Author
-
陆毅, 薛枫, 唐小波, 杨坤, 李益, and 马刚
- Abstract
Copyright of Zhejiang Electric Power is the property of Zhejiang Electric Power Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
46. Remote sensing inversion study of total organic carbon concentration in Karst Plateau Lakes-Taking Pingzhai reservoir as an example.
- Author
-
Rukai Xie, Zhongfa Zhou, Jie Kong, Yan Zou, Fuqiang Zhang, Li Li, Yanbi Wang, Cui Wang, and Caixia Ding
- Subjects
REMOTE sensing ,OPTICAL remote sensing ,WELLHEAD protection ,KARST ,REMOTE-sensing images ,WATER quality ,BODIES of water - Abstract
Currently, the inversion of remote sensing satellite images of water environment indicators mostly stays in the indicators with active optical characteristics, while there is less research on the inversion of most water quality indicators with non-optical activity properties, weak scattering and absorption of optical radiation, the size of their concentration has little effect on the spectral characteristics of the water body, such as TOC(Total Organic Carbon). In this paper, based on Pingzhai Reservoir, a dammed river in the karst mountainous area, the inversion model of TOC concentration was established based on BP neural network (BPNN) and sentinel-2 satellite remote sensing images. The results showed that the single bands with high correlation with the measured TOC concentration data were two vegetation red-edge bands B6 (740 nm) and B7 (783 nm) and one NIR band B8 (842 nm), and finally b7, b6 + b7, b7 + b8, b7 ×b8 were selected as the input layers of BPNN for modeling through the combination of the bands, and their Pearson's coefficients were -0.667, -0.656, -0.655, - 0.675. The inverse model established could reach a minimum RMSE of 0.235 mg/L and a maximum R2 of 0.889, which was superior to that of the conventional empirical model. Demonstrate the feasibility of a TOC inversion method based on Sentinel-2 data and BPNN to monitor TOC concentrations in Pingzhai Reservoir. The study successfully established a BP neural network inversion model of TOC concentration in Pingzhai Reservoir with low error, meanwhile, we analyzed the correlation between common water quality indicators and TOC in the reservoir, in which TOC showed significant positive correlation with WT and significant negative correlation with TN and EC, with Pearson's coefficients of 0.655, -0.666, and -0.393, respectively. The article provides scientific theoretical foundation and technical support for water quality protection of water sources. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
47. Anti-Icing System Performance Prediction Using POD and PSO-BP Neural Networks.
- Author
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Mao, Handong, Lin, Xiaodan, Li, Zhimao, Shen, Xiaobin, and Zhao, Wenzhao
- Subjects
SKIN temperature ,ARTIFICIAL neural networks ,ICE prevention & control ,PROPER orthogonal decomposition ,PARTICLE swarm optimization ,BACK propagation - Abstract
The anti-icing system is important for ice protection and flight safety. Rapid prediction of the anti-icing system's performance is critical to reducing the design time and increasing efficiency. The paper proposes a method to quickly predict the anti-icing performance of the hot air anti-icing system. The method is based on Proper Orthogonal Decomposition (POD) and Back Propagation (BP) neural networks improved with the Particle Swarm Optimization (PSO) algorithm to construct the PSO-BP neural network. POD is utilized for data compression and feature extraction for the skin temperature and runback water obtained by numerical calculation. A lower-dimensional approximation is derived from the projection subspace, which consists of a set of basis modes. The PSO-BP neural network establishes the mapping relationship between the flight condition parameters (including flight height, atmospheric temperature, flight speed, median volume diameter, and liquid water content) and the characteristic coefficients. The results show that the average absolute errors of prediction with the PSO-BP neural network model on skin temperature and runback water thickness are 3.87 K and 0.93 μm, respectively. The method can provide an effective tool for iteratively optimizing hot air anti-icing system design. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. Multi-Physics Coupled Acoustic-Mechanics Analysis and Synergetic Optimization for a Twin-Fluid Atomization Nozzle.
- Author
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Li, Wenying, Li, Yanying, Lu, Yingjie, Xu, Jinhuan, Chen, Bo, Zhang, Li, and Li, Yanbiao
- Abstract
Fine particulate matter produced during the rapid industrialization over the past decades can cause significant harm to human health. Twin-fluid atomization technology is an effective means of controlling fine particulate matter pollution. In this paper, the influences of the main parameters on the droplet size, effective atomization range and sound pressure level (SPL) of a twin-fluid nozzle (TFN) are investigated, and in order to improve the atomization performance, a multi-objective synergetic optimization algorithm is presented. A multi-physics coupled acoustic-mechanics model based on the discrete phase model (DPM), large eddy simulation (LES) model, and Ffowcs Williams-Hawkings (FW-H) model is established, and the numerical simulation results of the multi-physics coupled acoustic-mechanics method are verified via experimental comparison. Based on the analysis of the multi-physics coupled acoustic-mechanics numerical simulation results, the effects of the water flow on the characteristics of the atomization flow distribution were obtained. A multi-physics coupled acoustic-mechanics numerical simulation result was employed to establish an orthogonal test database, and a multi-objective synergetic optimization algorithm was adopted to optimize the key parameters of the TFN. The optimal parameters are as follows: A gas flow of 0.94 m
3 /h, water flow of 0.0237 m3 /h, orifice diameter of the self-excited vibrating cavity (SVC) of 1.19 mm, SVC orifice depth of 0.53 mm, distance between SVC and the outlet of nozzle of 5.11 mm, and a nozzle outlet diameter of 3.15 mm. The droplet particle size in the atomization flow field was significantly reduced, the spray distance improved by 71.56%, and the SPL data at each corresponding measurement point decreased by an average of 38.96%. The conclusions of this study offer a references for future TFN research. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
49. Quantitative Detection for Fatigue Natural Crack in Aero-Aluminum Alloy Based on Pulsed Eddy Current Technique.
- Author
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Sun, Cheng, Yu, Yating, Li, Hanchao, Wang, Fenglong, and Liu, Dong
- Subjects
FATIGUE cracks ,ALUMINUM alloys ,AEROSPACE materials ,AEROSPACE engineering ,ALLOYS ,EDDIES - Abstract
Aero-space aluminum alloys, as vital materials in aerospace engineering, find extensive application in various aerospace components. However, prolonged usage often leads to the emergence of fatigue natural cracks, posing significant safety risks. Therefore, research on accurate quantitative detection techniques for the cracks in aerospace-aluminum alloys is of vital importance. Firstly, based on the three-points bending experimental model, this paper prepared the fatigue natural crack specimen, and the depth of the natural crack is calibrated. Then, given the complexity of geometric characteristics inherent in natural cracks, the pulsed eddy current signal under the different natural crack depth is acquired and analyzed using an experimental study. Finally, to better exhibit the non-linearity between PEC signal and crack depth, a GA-based BPNN algorithm is proposed. The Latin Hypercube method is considered to optimize the population distribution in the genetic algorithm. The results indicate that the characterization accuracy reaches 2.19% for the natural crack. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. Study on Hydrocarbon Fuel Ignition Characterization Based on Optimized BP Neural Network.
- Author
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Chen, Zhihan, Wei, Lulin, Ma, Hongan, Liu, Yang, Yue, Meng, and Shi, Junrui
- Subjects
ARTIFICIAL neural networks ,PARTICLE swarm optimization ,COMBUSTION efficiency ,ENERGY consumption ,AIRCRAFT fuels - Abstract
The investigation of the ignition delay of hydrocarbon fuel is highly valuable for enhancing combustion efficiency, optimizing fuel thermal efficiency, and mitigating pollutant emissions. This paper has developed a BP-MRPSO neural network model for studying hydrocarbon fuel ignition and clarified the novelty of this model compared to the traditional BP and ANN models from the literature. The model integrates the particle swarm optimization (PSO) algorithm with MapReduce-based parallel processing technology. This integration improves the prediction accuracy and processing efficiency of the model. Compared to the traditional BP model, the BP-MRPSO model can increase the average correlation coefficient, from 0.9745 to 0.9896. The R
2 value for predicting fire characteristics using this model can exceed 90%. Meanwhile, when the two hidden layers of both the BP and BP-MRPSO models consist of 9 and 8 neurons, respectively, the accuracy of the BP-MRPSO model is increased by 38.89% compared to the BP model. This proved that the new BP-MRPSO model has the capacity to handle large datasets while achieving great precision and efficiency. The findings could provide a new perspective for examining the properties of fuel ignition, which is expected to contribute to the development and assessment of aviation fuel ignition characteristics in the future. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
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