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Automatic transcription of sound signals can convert audio to musical notes, which has significant research value. This paper extracted dual-channel constant Q transform (CQT) spectra from piano audio as features. In the design of the automatic transcription model, a CNN was employed to extract local features and then combined with a Transformer model to obtain global features. A CNN-Transformer automatic transcription model was established using a two-layer CNN and three-layer Transformers. Experiments were conducted on the MAPS and MAESTRO datasets. The results showed that dual-channel CQT outperformed short-time Fourier transform (STFT) and mono CQT in auto-transcription. Dual-channel CQT achieved the best results on frame-level transcription for the MAPS dataset, with a P value of 0.9115, an R value of 0.8055, and an F1 value of 0.8551. A sliding window with seven frames yielded the best transcription results. Compared with the deep neural network and CNN models, the CNN-Transformer model demonstrated superior performance, achieving an F1 value of 0.8551 and 0.9042 at the frame level for MAPS and MAESTRO datasets, respectively. These findings confirm the designed model's reliability for automatic piano audio transcription and highlight its practical applicability.

Landslides, as a common geological hazard, pose a significant threat to critical infrastructure such as pipelines. With numerous large-scale engineering projects in China crossing active fault zones, the impact of geological hazards on the safe operation of pipelines is becoming increasingly prominent. To accurately assess the impact of landslides on pipelines, this study employs the open-source DualSPHysics code and constructs a three-dimensional numerical model of landslide impact on pipelines based on the Smoothed Particle Hydrodynamics (SPH) method. The study conducts a quantitative analysis of key factors such as sliding displacement and landslide scale, thoroughly exploring the mechanisms by which landslides affect pipelines. The results indicate that as the landslide displacement increases, the rate at which the pipeline's stress increases accelerates, and the rate of stress decrease after reaching the peak also accelerates. Additionally, when the width of the landslide mass increases, its volume correspondingly increases, leading to a significant enhancement in the impact force experienced by the pipeline. Furthermore, the study analyzes the impact of different initial distances between SPH particles on the pipeline to optimize the accuracy and computational efficiency of the simulations. This research not only provides new perspectives and approaches for assessing pipeline safety but also holds significant implications for enhancing pipeline disaster resistance and guiding design and safety assessments in geological engineering and infrastructure projects.

This paper focuses on the gear whine noise problem of this engine, analyses it from two aspects of excitation source and transmission path, and puts forward the corresponding optimization method in combination with the actual product, which mainly includes the enhancement of the intrinsic frequency of the engine assembly, the optimization of the gear macro-parameters and the optimization of the gear micro-parameters. The optimization scheme achieves the objectives of minimizing transmission error and optimizing gear contact surface pressure and improves the NVH performance of the gear while considering the reliability of the gear system. Finally, the feasibility of the optimization scheme is verified by engine noise bench test. The study's results offer valuable insights for the design of diesel engine front-end gear systems, providing an effective approach to address existing product issues and to guide the development of new products.

The oil pipeline is a critical component that influences the vibration and noise levels of the hydraulic system. Inadequate design may result in resonance or leakage issues, rendering it susceptible to external vibration excitation. To enhance the reliability of the hydraulic pipeline, simulations and analyses were conducted on its modal, harmonic response, and fatigue characteristics. Based on the results of harmonic response analysis and strength analysis, an effective reinforcement scheme was proposed and validated. By inputting the acceleration load to the pipeline system for frequency response analysis, the influence of different excitation forces on the pipeline stress can be determined. The findings indicate that pipeline vibration primarily occurs in the outlet pipe of the transmission, with significant stress and vibration displacement observed at the thermostat valve support. Following structural improvements, there was a notable reduction in stress levels at the transmission outlet pipe, along with a shift in maximum stress position due to additional support. This enhancement has improved both structural stiffness of the outlet pipe and overall stability of the pipeline system.

The use of ultrasound in synthesis of polyvinylpyrrolidone copolymers with methacrylic esters as well as in the presence of calcium-containing mineral fillers has been researched. The influence of ultrasound on the polyvinylpyrrolidone destruction is determined. The activating impact of ultrasound on initiation of polymerization is confirmed. The ultrasound application significantly intensifies the process of porous composites obtaining that based on polymer-monomer compositions and calcium-containing mineral fillers including nanosized. The developed (nano)composites can be used in medicine to replace damaged bone tissue.

The response of oil tanks under dynamic loads is the key to ensuring safety, and the analysis of stiffness and strength is very necessary. Modal analysis was carried out on the oil tank to obtain the natural frequencies and vibration modes. Under specific excitation frequencies, the stress responses of the dangerous points of the front head, the rear head, the cylinder, and the transverse wave plate were calculated respectively. Three filling rates of 30 %, 50 % and 70 % were respectively selected for the structural response study, and the structural deformation and stress responses of the storage tank structure under the impact of different volumes of liquid were obtained. According to the dynamic response analysis, the structure of the front head and transverse wave plate were strengthened. It can be known from the comparison of mechanical properties that the optimized structure can significantly improve the stiffness and strength, and effectively ensure the safety of the oil tank.

The article examines the kinematic and force parameters involved in cutting paper stacks or book blocks with a disc knife installed with eccentricity. Due to the eccentricity, the knife blade oscillates radially relative to the material being processed, making the cutting process vibrational. Theoretical calculations of cutting forces during block processing have been carried out, and a comparison with experimental results is provided. Additionally, recommendations for designing advanced cutting machines are given.

In the era of fitness, more and more young people are familiar with Taijiquan, a kind of physical fitness exercise. By conducting biomechanical analyses of the movements of Taijiquan, it is possible to exercise the body better. Numerous techniques in Taijiquan make it difficult to study each individually. Therefore, this paper studied the movement of “wild horses’ mane parting” in terms of biomechanics by analyzing the joint angle, stiffness, and impulse during this movement. Twenty male athletes were selected as subjects and divided into a professional group and a beginner group according to their training periods. High-speed cameras were used to shoot the “wild horses’ mane parting” movement. The angles of lower limb joints in these athletes were measured to calculate joint impulse and stiffness. The results showed that, compared with the professional group, there were significant differences in the adduction and abduction angle and the internal and external rotation angle between the beginner group and the professional group in the single-leg support movement stage (P< 0.05). There were also significant differences in joint impulse and stiffness (P< 0.05). Compared with beginners, long-term professional practitioners can make their movements more standardized. By comparing movements and data analysis, beginners can make their movements more standardized when practicing Taijiquan and avoid the risk of sports injury. The novelty of this article lies in the use of high-speed cameras to capture athletes’ movements, enabling accurate analyses of their joints and providing effective references for precise training.