Journal of Mechanical Engineering, Automation and Control Systems
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Noise control of audio recognition equipment for multimedia system
Get PDFNoise control is one of the most critical technical indicators to improve the performance of intelligent audio recognition system. Based on the noise cancellation technology, a distributed low noise amplification circuit design was proposed, and the PE15-0P technology was applied to realize broadband low noise amplification. The amplifier circuit used diodes and resistors for voltage division, which effectively achieved bias saturation at the transistor and then diode structure. According to the design of low noise amplifier, the noise output characteristics were simulated and analyzed. An audio enhancement method based on noise type recognition was proposed, which can optimize noise estimation by selecting parameter combinations according to noise type, so as to improve the quality and intelligibility of noise frequency signals in various noise environments. From the aspects of hardware and algorithm design, the noise signal was comprehensively reduced, and the accuracy of audio recognition was significantly improved
Integration of robotics and automation in supply chain: a comprehensive review
Get PDFRobotics and automation have developed as key technologies for supply chain management as a result of the increased demand for quicker and more effective supply chains. Robotics and automation improve supply chain management by lowering long-haul expenses, boosting work and usage strength, reducing errors, declining repetitive stock checks, updating orchestrating, taking care of times, and assembling induction to the problematic and hazardous places. Robotics aids in design, creation, etc. Automation helps to do tasks that are often done by people through the use of self-operating physical machines, computer software, and other technology. Despite being widely accepted as a tool to aid in decision-making, supply chain management (SCM) has very seldom used AI and ML. This article investigates several AI and ML sub-fields that are best suited for resolving real-world SCM-related issues in order to fully realize the potential benefits of AI and Ml for SCM. In doing so, this article examines the track record of successful AI and ML applications to supply chain management and highlights the most fruitful SCM domains to apply AI and ML. And also find out the how robotics and automations helps in warehouse management. The most recent developments in robotics and automation for supply chain management are thoroughly reviewed in this paper. We first give a general overview of the difficulties that supply chain management faces before going over the many ways that robotics and automation are used at various points along the supply chain. Additionally, we go over the advantages of robots and automation in supply chain management, including higher efficiency, accuracy, lower costs, and improved safety. Lastly, we discuss some of the present drawbacks and difficulties associated with robots and automation in supply chain management and suggest some possible directions for further investigation
Structural design and dynamic characteristic analysis of adjustable badminton serving machine
Get PDFSystem dynamics serves as a crucial foundation for evaluating the performance of mechanical auxiliary equipment. To enhance the stability and reliability of the badminton launch process, structural design and dynamic analysis were conducted on a mode-adjustable, precise control badminton serving mechanism. The combination of eccentric crank-slider mechanism, stretched springs, and electromagnets was used in mechanical structures, which could effectively effectively improve the smoothness of the badminton in the launching process. The virtual prototype of badminton serving machine was established and imported into ADAMS for dynamic simulation analysis, verifying the correctness of the serving and retrieving mechanisms. Using the aerodynamic equations, the trajectory of badminton movement under different working parameters was simulated and analyzed. The dynamic analysis results show that the design of the launching and catching mechanisms is scientific and effective. The launch angle and initial velocity are the key factors that determine the trajectory of the badminton
Structural analysis and optimal design of a spherical thin-walled stainless steel water tank without reinforced tie ribs
No full textA spherical thin-walled stainless steel water tank without reinforced tie ribs has been designed to address the issues of easy fracture and corrosion of the ribs, difficulty in maintenance and cleaning, and short service life exposed during the use of thin-walled stainless steel water tanks with reinforced tie ribs. Firstly, an analytical model of a flat steel thin-walled water tank without reinforced tie ribs was established and subjected to static analysis under water pressure. The deformation and stress distribution patterns of the side molded plate of the flat box were obtained. Secondly, a spherical non ribbed thin-walled stainless steel water tank structure was designed with circular cross-section under different box bulge parameters, and its mechanical response characteristics under water pressure load were analyzed. A strengthening scheme was designed for the bottom box molded plate. Once again, optimize the combination design of the box scheme and the reinforcement scheme, and analyze their static, thermodynamic, and thermal solid coupling performance. Finally, the Latin Hypercube Sampling method was used to generate experimental design samples, and a response surface approximation model of a spherical thin-walled stainless steel water tank without reinforced tie ribs was constructed. The wall thickness of the box molded plate, skeleton, and reinforcement were used as design variables, and the maximum deformation and maximum equivalent stress were used as constraints. The lightweight design was carried out with the goal of minimizing mass. The research results indicate that the design program and parameter selection method for spherical thin-walled stainless steel water tanks without reinforced tie ribs proposed in the article are efficient and feasible, and can provide technical reference and theoretical support for the layout and overall optimization design of non ribbed thin-walled stainless steel water tank structures
Modal analysis of key components of crusher based on digital simulation technology
No full textThe modal characteristics of the crusher rotor and shell constitute the crucial factors influencing vibration and noise. Based on the principle of simplification, the rotor component model was established. Through mesh optimization, the model accuracy and calculation efficiency can be ensured, and the calculation of natural frequency and modal shapes was completed based on ANSYS. To verify the accuracy of the finite element model, the modal test was carried out by the hammering method. Sensors were set in three different directions to obtain the frequency response function and the modal assurance criterion matrix mode confidence criterion. Using the same research method, the modal characteristics of the shell model were simulated and analyzed. The research results show that the modal parameters identified by the modal test are basically consistent with the simulation model. The natural frequencies of the rotor and the shell are quite different from the excitation frequency of the motor, and resonance problems will not occur when the crusher is proper functioning
Modal analysis and structural noise control of vehicle body frame
Get PDFThe structural noise inside the vehicle cabin is mainly low-frequency vibration, which is closely related to the modal characteristics of the vehicle frame. The finite element method was used to simulate and calculate the body frame under free modal conditions, and the first four effective modal shapes were obtained. The calculation error of the natural frequencies was verified through modal experiments. Taking structural stiffness into account, a sound-structure coupled model was established. The suspension connection point was selected as the excitation point, and a one-way dynamic load was applied to obtain the noise and vibration responses of the front and rear rows. Based on the modal analysis results, the top-roof reinforcement scheme was adopted to verify the noise suppression effect of the structure. The results show that the optimized structure can effectively suppress structural noise, which plays an important role in improving the NVH characteristics
Reliability analysis of cable crimping terminals with different applicator tools
Get PDFThis study provides a comprehensive evaluation of the stability of crimping of the same terminal on FLRY A cables using three different applicators. The research involved conducting pull tests on 50 samples for each applicator type, analyzing the results using Minitab software to assess the consistency and strength of the crimp connections. The findings indicate that while the Demirel applicator produces the highest average pull test values, the Tyco applicator demonstrates superior consistency, making it more suitable for applications where process stability is critical
A study into the fluid power control characteristics of a hydrostatic transmission for mobile machinery
Get PDFIn response to improve the quality and level of hydrostatic transmission (HST) products for modern mobile machineries, the closed-loop transfer functions of a HST are established by mathematical modeling, a comprehensive testing equipment is developed employing a proportional relief valve for automatic program loading and fuzzy-PID oil temperature control, the testing equipment is capable of conducting various performance tests for various models of HST integrated pump-motor products, including factory and type tests, especially continuous impact and endurance performance tests under high temperature and high-speed conditions. Comprehensive performance test of the above test sample is carried out using the developed equipment, that the test results agree well with the previous simulation results verifies the correctness of the established theoretical analysis model. The obtained theory and equipment from this work provide theoretical and experimental technical support for improving design and development of high-end fluid components for modern mobile machinery HST
Research on quantitative design methods for the durability of reinforced concrete structures in a hot ocean environment
Get PDFThis paper establishes a quantitative design method for the durability of concrete structures in cross-sea bridges through investigation, rapid chloride migration coefficient method (RCM) and theoretical calculation, considering the impact of temperature on chloride ion diffusion rates in a hot marine salt erosion environment. Combined with the RCM test and bridge service data, a quantitative design method for bridge concrete durability is proposed. Test results show that the growth rate of the chloride ion diffusion coefficient of concrete is approximately 1.028 for every 1 °C increase. For every 5 °C increase, the growth rate of the chloride diffusion coefficient of concrete is about 1.15, and the cover depth of the concrete structure should be multiplied by a coefficient of 1.07. Therefore, the concrete cover depth should be appropriately increased, considering the influence of ambient temperature. Furthermore, fly ash, slag, and stone powder can increase the concrete’s resistance to chloride corrosion. When the influence of temperature on the chloride ion diffusion coefficient is considered, the durability design of the concrete structure of the sea-crossing bridge is conducted, which is beneficial for ensuring their service life
Evaluating the impact of microstructure modifications on thin film photoelectric properties
Get PDFMicrostructure modifications on thin photoelectrical properties refers to changes in the microscopic structure of thin films that affect their ability to convert light into electricity. This study investigates the deposition and post-treatment effects in the electric and visual qualities of GZO, IZO, and ZnO thin layers, aiming to enhance their applicability in electronic and optoelectronic devices, according to the X-raydiffraction (XRD) examination. Thin films were deposited on glass substrates using magnetic sparking at thicknesses of 300 nm and 500 nm, followed by treatments like wet aging and annealing at 220 °C. The results showed significant improvements in crystallinity and optical characteristics, with ZnO films exhibiting a preferred (003) orientation. IZO films demonstrated notable mobility at 10.96 cm2/V-sec and resistivity of 2.49×10⁻3 ohm-cm. The novelty of this research is the novel integration of wet aging and low-temperature annealing, that notably improves thin film efficiency while maintaining structural integrity. The findings indicate that post-treatment significantly enhances the properties of these thin films, suggesting their potential for various electronic applications