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Introduction: Accurate prediction of line losses in distribution networks is crucial for optimizing power system planning and network restructuring, as these losses significantly impact grid operation quality. This paper proposes a novel approach that combines advanced feature selection techniques with Stacking ensemble learning to enhance the effectiveness of distribution network loss analysis and assessment. Methods: Utilizing data from 44 substations over an 18-month period, we integrated a Stacking ensemble learning model with multiple feature selection methods, including correlation coefficient, maximum information coefficient, and tree-based techniques. These methods were employed to identify the key predictors of power loss in the distribution network. Results: The proposed model achieved a Mean Absolute Percentage Error (MAPE) of 3.78% and a Root Mean Square Error (RMSE) of 1.53, demonstrating a substantial improvement over traditional linear regression-based prediction methods. The analysis revealed that historical line loss and line active power were the most influential predictive variables, while the inclusion of time-related features further refined the model's performance. Discussion: This study highlights the efficacy of combining multiple feature selection methods with Stacking ensemble learning for predicting power loss in 10 kV distribution networks. The enhanced accuracy and reliability of the proposed model offer valuable insights for electrical engineering applications, potentially contributing to more efficient and sustainable energy distribution systems. Future research could explore the applicability of this approach to other distribution network voltage levels and investigate the incorporation of additional environmental and network-specific factors to further improve power loss prediction. [ABSTRACT FROM AUTHOR]

Energy meters, traditionally used in residential, commercial, and industrial settings to measure and record electrical energy usage, play a critical role in billing and energy management. In the realm of sports, where facilities often encompass a variety of high-energy-consuming activities ranging from lighting vast stadiums to powering high-intensity training equipment, efficient energy management becomes crucial for both operational sustainability and financial viability. This study explores the adoption of a smart energy meter equipped with Internet of Things (IoT) technology, specifically tailored for the unique energy demands of sports facilities. The advanced smart energy meter utilizes an Improved Fast Fourier Transform (IFFT) to manage and monitor energy usage more effectively in sports environments. This approach includes Total Harmonic Distortion (THD) Computing and Root Mean Square Voltage (RMSV) Measurement, which are critical for accurately determining Vrms and THD values. Such precise measurements are essential for sports facilities to prevent energy waste and ensure the reliability of critical systems like field lighting and climate controls, which directly affect athletic performance and spectator experience. Furthermore, the integration of the Hanning Window (HW) method reduces spectrum leakage, enhancing the reliability of harmonic analysis. This is particularly important in sports complexes where sudden changes in energy use--such as those occurring during major events or games--can lead to significant fluctuations. Reliable harmonic analysis helps in maintaining consistent power quality, protecting sensitive training equipment from potential damage caused by power irregularities. Using Node-RED, a cloud-based platform, the smart energy meter facilitates the secure collection, management, and transfer of energy data, enabling sports facility managers to perform realtime monitoring and make informed decisions regarding energy use. A comparative analysis against traditional Discrete Fourier Transform (DFT) and Fast Fourier Transform (FFT) methods highlights the superiority of the IFFT approach in sports settings, demonstrating its enhanced capabilities in power quality management and operational efficiency. In conclusion, the implementation of smart energy meter technology in sports facilities not only enhances energy efficiency and reduces costs but also plays a crucial role in optimizing the performance and sustainability of sports operations. This technology supports the broader goals of environmental stewardship and economic management in the sports industry, ensuring that facilities can meet the high standards required for both competition and training. [ABSTRACT FROM AUTHOR]

Timber–concrete composite (TCC) structure system is most frequently used in large-span structures. Recently, a performance-based fire safety design method named improved travelling fires methodology (iTFM), which is suitable for long-span structures, has been developed. In this article, an energy-based time equivalent method (EBTEM) is proposed, while its effectiveness is experimentally verified. The proposed method can be used to evaluate the fire resistance of the TCC structures subjected to iTFM fires. The results indicated that the damage degree at different spatial positions of the TCC structure under the same fire size was different, and the location with the least and most serious damages occurs towards the beginning and middle of the fire path, respectively. The results show that this difference in damage degree mainly depends on the fire size, and the difference becomes less pronounced as the fire size increases. Concomitantly, it can be obtained that the damage degree under the different fire sizes was different, and the smaller the fire size, the greater the damage degree. Hence, when the EBTEM is adopted to design the TCC structures exposed to iTFM fires, the setting of fire protection target is largely determined by the actual fire size. [ABSTRACT FROM AUTHOR]

Objective To observe the clinical efficacy of hip joint rotative extending manupilation in the treatment of primary and early knee osteoarthritis (KOA). Methods From September 2022 to May 2023, a total of 148 patients with primary and early KOA were recruited from The First Affiliated Hospital of Hebei University of Chinese Medicine. According to the random numbers generated from computer, the patients were randomly divided into the experimental group (74 cases, including eight dropouts) and the control group (74 cases, including 11 dropouts). Both groups received health education, while the experimental group additionally underwent hip joint rotative extending manupilation every two days, the control group received oral diclofenac sodium sustained-release tablets (75 mg/d). Both groups were treated for 2 weeks. The visual analogue scale (VAS) score and the Western Ontario and McMaster University (WOMAC) osteoarthritis index score were compared between the two groups at three time points: before treatment, after treatment, and at follow-up (2 weeks after treatment). The 36-item Short- Form (SF-36) scale score was compared between the two groups at two time points: before treatment and at follow-up. The clinical efficacy was evaluated. Results The VAS score and WOMAC osteoarthritis index score of the two groups after treatment and at follow-up were lower than those before treatment, and the VAS score and WOMAC osteoarthritis index score of the experimental group were lower than those of the control group (P<0. 05). The SF-36 scale score was higher in the experimental group than that in the control group at follow-up (P<0.05). The total effective rate was 90.9% in the experimental group, which was higher than 79. 3% in the control group (P<0. 05). Conclusion Hip joint rotative extending manupilation is effective for relieving pain, alleviating clinical symptoms, and improving joint function in patients with primary and early KOA. It is more effective than oral diclofenac sodium sustained-release tablets and has greater clinical application value. This may be attributed to manual adjustment of the femur rotation status and the relative position between the femoral head and the acetabulum, correcting the abnormal force line of the lower limbs, and balancing the weight-bearing state of the knee joint, so as to achieve the effect of treating KOA. [ABSTRACT FROM AUTHOR]