bluuebunny/crossref_metadata_2025 huggingface dataset:
Inferring precocial Chinook Salmon production through single-parentage assignments
Authors: Steele Craig A. , Harris Audrey , Campbell Matthew , Venditti David A.
Published: June 2024

Objective

Parentage analysis is a routine methodology in fisheries research, but study systems exist where it is impractical to sample both parents. The ability to reliably assign offspring to a single parent is beneficial in these situations. We applied single-parentage assignments to a naturally spawning population of Chinook Salmon Oncorhynchus tshawytscha to quantify production of anadromous returns by unsampled precocial males.

Methods

We used an approach that focused on two important aspects of parentage analyses: (1) addressing the presence of family structure within the set of sampled parents and (2) controlling for false-positive and false-negative assignments.

Result

Results indicated that 30% of reproductively successful males were precocial males, which produced 20% of the returning anadromous offspring.

Conclusion

This study provides a framework for applying single-parent assignments in a salmonid study system while explicitly addressing sources of assignment errors.
Survey and Analysis for High Power Factor IPMSM Drive System Using Electrolytic Capacitor‐Less Inverter
Authors: Ohishi Kiyoshi , Haga Hitoshi , Abe Kodai
Published: June 2024

Home appliances such as residential air conditioners are based on the variable speed drives for AC motors such as IPMSM and IM. These variable speed drives always require the simple and low‐cost system configurations without the large electrolytic capacitors, reactors, and power devices that consist of PFC converters. This paper surveys and analyzes the proposed and advanced control techniques to achieve high input power factor and sinusoidal source current control in electrolytic capacitor‐less inverters. The investigated control methods consist of control algorithms based on the energy flow between input and output of the electrolytic capacitor‐less inverter, and all of them are useful as high‐power factor control methods for compressor drive motors such as air conditioners. Moreover, these techniques realize the variable speed drives for AC motors to meet power supply harmonics regulations (IEC61000‐3‐2). © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.
Freedom and Responsibility
Authors: Feltz Adam , Cokely Edward T.
Published: June 2024

Judgments about freedom and moral responsibility have been argued to be essential to how we view ourselves and others. Being free and morally responsible (or at least a belief to that effect) has been argued to underwrite elements of human existence ranging from one’s sense of self-worth to having genuine, loving relationships. One extensively explored question in the philosophical literature about freedom and moral responsibility is: can you be free and morally responsible if all your actions are determined? There is substantial philosophical disagreement about the right answer to that question. Those who answer “yes” are called compatibilists and those who answer “no” are called incompatibilists. This chapter documents extensive evidence using representative and diverse materials and methods indicating that the global personality trait extraversion predicts those who tend to be compatibilists. These relations have also been observed to exist in diverse cultures and languages (e.g., those who speak English, Spanish, or German in North America and Europe). The evidence presented in this chapter represents the paradigmatic example in our book of personality predicting philosophically relevant judgments.
Philosophical Expertise
Authors: Feltz Adam , Cokely Edward T.
Published: June 2024

In this chapter we directly address one of the prominent objections to generalizing studies done on non-professional philosophers to experts in philosophy. The Expertise Defense holds that because of the special training, knowledge, or skills of professional philosophers, the potentially problematic biases found in non-professional philosophers will not likely be found in expert philosophers. To assess this argument, we provide a substantial discussion on how expertise is acquired. We focus on the facts that experts are always made and not born, general intelligence cannot explain all there is to expertise, and experts have different knowledge and skills than non-experts. We then use these general points to argue that philosophers are not likely to have the relevant kinds of learning environments, skills, or knowledge that prevents them from being biased in potentially problematic ways. We report results directly testing whether extraversion predicts compatibilist judgments about freedom and moral responsibility in philosophical experts, finding that indeed expert philosophers tend to be biased by their heritable personality traits. We conclude that without further evidence, we do not have reason to think that philosophical expertise will eliminate potentially problematic biases in philosophically relevant judgments.
The Philosophical Personality Argument
Authors: Feltz Adam , Cokely Edward T.
Published: June 2024

The philosophical heart of this book is embodied in the Philosophical Personality Argument, which is:

Philosophically relevant intuitions are used as some evidence for the truth of some philosophical claims.

Some differences in philosophically relevant intuitions used as evidence for the truth of some philosophical claims are systematically related to some differences in personality.

If philosophically relevant intuitions are used as some evidence for the truth of some philosophical claims and those intuitions are systematically related to some differences in personality, then one’s endorsement of some philosophical claims is at least partially a function of one’s personality.

Therefore, one’s endorsement of some philosophical claims is at least partially a function of one’s personality.

In this chapter, we provide reasons to think (1) is true. We review evidence from Chaps. 2–4 providing reasons to think (2) is true. We discuss how premise (3) seems to capture standard ways that intuitions could be used as evidence. We then argue that the conclusion (4) poses substantial challenges to some philosophical projects (e.g., Neo-Platonic projects) but not necessarily others (e.g., conceptual analysis). We then defend premises 1–3 from several objections.
Mixed Linear Quadratic Regulator Controller Design for Path Tracking Control of Autonomous Tracked Vehicles
Authors: Tian Baiyu , Lin Tianliang , Zhang Chunhui , Li Zhongshen , Fu Shengjie , Chen Qihuai
Published: June 2024

With the advancements in autonomous driving technology, artificial intelligence and computer science have facilitated the autonomous operation of machinery. Industrial production efficiency is enhanced by this autonomy in construction machinery. Furthermore, personal safety for machine operators is also improved. Among these advancements, path tracking control emerges as a critical component for the automation of construction machinery. It primarily focuses on the lateral and longitudinal control of the machinery, enabling stable tracking of a predefined path even under challenging operational conditions. To enhance the accuracy and robustness of path tracking, this paper proposes a mixed linear quadratic regulator (LQR) controller specifically designed for autonomous tracked vehicles. This approach uses the LQR control algorithm to suppress the noise generated by complex construction environments and accurately track the desired path. The effectiveness and practicality of this method are validated through simulation experiments.
Simulation and Comparative Analysis of Welding of the Safety End of the Pipe Based on Different Body Heat Source Models
Authors: Chen Wenjie , Ji Dongmei
Published: June 2024

Based on ANSYS APDL, this paper simulates the welding process of the safety end of the pipe using different heat source models. The results show that the shape of the moving heat source under the body heat rate heat source model and the double ellipsoid heat source model is ellipsoidal shape. The body heat rate heat source has a larger high temperature area than the double ellipsoidal heat source. The variation law of temperature field and stress field is basically the same, but the overall stress field under double ellipsoid heat source load is about 20 MPa smaller than the total stress field under body heating rate. The comparison of different heat source models can provide some help for the numerical simulation of welding.
Dynamical Simulation Analysis of Faulty Gearbox in Quay Crane Under Dynamic Load
Authors: Feng Wenzong , Zhang Qing , Chen Zhuoxiang , Zhang Jianqun , Wang Haoyu
Published: June 2024

Dynamics simulations with faults can elucidate fault vibration characteristics, yet the vibrational properties of the quay crane lifting gearboxes under dynamic load excitation remain unclear. Based on multi-body dynamics theory, a multi-body dynamical model of the quay crane gearbox is established, simulating dynamic load excitation caused by cables and containers during the operation of a quay crane. The vibration responses under various working conditions and load types of different gear states are analyzed, and the corresponding fault frequency features are extracted by envelope spectrum. Simulations indicate that local gear faults enlarge the amplitude of gearbox vibrations, inducing the phenomenon of gear mesh frequency and its harmonics modulated by gear fault frequency. Based on these studies, a testbed for the quay crane gearbox is constructed. The experiment verifies the accuracy of the dynamic model and reveals that the simulation signal of load-as-dynamic-load is more consistent with reality than static load. The results provide a basis for fault diagnosis of quay crane lifting gearboxes under dynamic load, and can offer simulation data support for intelligent diagnosis models lacking fault samples.
Optimal Design of Frame Structure of Center Axle Trailer Under Heavy Load Conditions
Authors: Gao Dongyu , Ma Jinyu , Zheng Huisai , Zhang Menzhe , Zhao Jingyi
Published: June 2024

In recent years, the mid axle train has gradually entered the transportation market because of its large loading capacity and flexible steering. The static simulation of full load bending, full load torsion and full load braking were carried out for the upper and lower platforms of the trailer frame, and the stress and deformation were obtained. Through the topology optimization design, the pseudo density cloud image with material removal as the optimization objective was obtained. The response surface optimization method was used to adjust the main optimization parameters of the frame platform, and the sensitivity value of its influence on the strength, stiffness and mass of the lightweight frame was analyzed. Finally, the actual value of the optimization parameters was determined. The results showed that the strength, stiffness, and stability of the lightweight frame met the requirements, and the total weight loss of the lightweight frame is 437.07 kg, and the weight loss ratio reached 14.51%. Finally, the static strength test of the lightweight frame was carried out, and the results showed that the lightweight frame met the use requirements.
Characterization of Solder Mechanical Properties Based on Nanoindentation
Authors: Sheng Wenjun , Wang Zhihai , Cheng Huiming
Published: June 2024

This article systematically elaborates on the in-situ measurement of solder using nanoindentation technology, and combines numerical inversion methods to analyze its elastic–plastic and creep mechanical properties. The elastic–plastic and creep constitutive equations of solder are constructed, and the influence of temperature on the elastic–plastic and creep characteristic of solder is studied. This provides an effective in-situ measurement and analysis method for characterizing the mechanical properties of high-density micro solder interconnection structures in radar electronic equipment.
The Research on Structural Design of Vehicle Integrated Display and Control Console
Authors: Luo Xiancheng
Published: June 2024

The display console and vehicle platform designed in this paper adopt an integrated structure design, the structure is simple and beautiful, easy to operate and easy to maintain, and the standard function module is selected as far as possible to meet the standardization requirements. Based on the design idea of generalization, serialization and combination, the display console is divided into unit design, which can be successively divided into: display unit, control unit, display and control processing unit and cabinet unit. Among them, the display unit and control unit learn from the mature design technology to ensure the design quality; The display and control processing unit is designed separately, with rigid connections to both the display unit and control unit externally, and the internal air duct is set up to meet the heat dissipation requirements. The cabinet unit is arranged under the display and control processing unit and the two are rigidly connected to ensure the overall structural rigidity and provide required installation space for user devices. The display console adopts split designs to support quick installation, disassembly and handling of four units. 3D design software is used to analyse the installation space, visual field, hand operation space, knee space and maintenance space of the display console to ensure that the display console has a good human–computer interaction function. The internal space of the display console is designed with three-dimensional wiring, the routing path of each cable in each unit is planned, and the cable can be customized in advance, which greatly improves the efficiency of on-site electrical assembly. Mechanical analysis software is used to simulate the main structure of the display console to ensure that the whole display console meets the mechanical performance requirements. The above design and analysis have certain guiding significance for similar design work of vehicle display console.
Fault Simulation and Experimental Validation of Accessory Transmission System
Authors: Sun Yu , Cao Xuyang , Yuan Yunbo , Zhao Guang , Ma Song , Li Haofan
Published: June 2024

As an important part of the aero-engine, the accessory transmission system affects the operation status of the engine, and it is of great significance to carry out fault mechanism analysis and fault identification. This paper takes a certain type of aero-engine accessory transmission system as the research object, flexes the box using ANSYS, establishes a rigid-flexible coupling model under normal working conditions and fault conditions through ADAMS, and studies the vibration characteristics in single fault and multi-fault combination modes, such as unbalance of the shaft system, gear misalignment and gear broken tooth. Considering different load loading conditions, the dynamic simulation of the transmission system is carried out, the shafting displacement and box acceleration response are extracted, the time–frequency domain feature information of the vibration signal is analyzed, and the fault characteristics and fault types are corresponded one-to-one. The test bench for the principle prototype of the accessory transmission system is designed and built, and the experimental research is carried out. The results show that the simulation results have good consistency with the principle prototype test results, which verifies the rationality of the simulation model.
Lateral Control of Autonomous Concrete Mixer Truck Based on Multiple Look Ahead Distances and Fuzzy Controller
Authors: Fu Ling , Yang Qiangrong , Liu Yanbin
Published: June 2024

Automated driving and working have been attracted considerable attention in the construction machinery industry due to their safety and efficiency. In this paper, multiple look ahead distances are calculated for lateral error and heading-angle error and multiple fuzzy inference engines are proposed with vehicle speed and the above-mentioned errors. Moreover, a kinematic model of mixer truck was proposed in this paper to address the length and width of the concrete mixer truck. Satisfactory simulation and experimental results have been obtained for different reference paths.
Research on Bilateral Servo Control Strategy for the 3T Redundant Freedom Parallel Robot
Authors: Gong Mingde , Hu Kongming , Zhang Yue
Published: June 2024

In this paper, a force feedback position bilateral servo control strategy with position difference compensation for a 3T redundant degree of freedom parallel robot is proposed. We have designed master and slave controllers based on fuzzy control, and conducted single motor bilateral servo control experiments and single branch bilateral servo control experiments on the experimental platform. The experimental results show that this method can effectively reduce the error accumulation caused by using non redundant inverse kinematics methods to solve redundant parallel robots, and maintain good position following performance of the master slave robot, Improved the transparency of force displacement control in the master–slave remote control robot system.
A Review of Intelligent Vehicle Trajectory Tracking Control Methods Based on Overtaking Lane Change Scenarios
Authors: Yang Dongzhao , Hu Lin , Yi Xiaojian , Zhang Xin
Published: June 2024

In order to achieve safe, comfortable, and stable control of lane-changing trajectories for intelligent vehicles, this paper reviews various trajectory tracking control methods for intelligent vehicles. Focusing on overtaking lane-changing trajectories, the paper provides a comprehensive review of research progress in PID, LQR, MPC, and SMC control methods both domestically and internationally. Striking a balance between addressing the challenges posed by non-integrity and multiple constraints of the vehicle, coping with the time-variability of the vehicle dynamics model, and ensuring the accuracy and computational efficiency of the vehicle model is essential for fostering the continuous development and enhancement of intelligent vehicle technology.
Dynamic Synovial Control Method of Four-Cable-Driven Parallel Robot Based on Interference Observer
Authors: Zhang Ke , Xu Jiabao , Tong Shenghao , Shi Huaitao , Duo Zhiqiang , He Cai
Published: June 2024

Aiming at the problem of high-precision trajectory tracking of four-cable-driven parallel robot, a dynamic non-singular fast terminal sliding mode surface based on the estimation output of interference observer is proposed. Firstly, based on the combination of traditional fast terminal sliding mode control and non-singular terminal synovial control, the estimation value of interference observer is introduced, and a new nonlinear sliding mode surface is established to suppress the influence of unknown disturbance, and at the same time track the desired trajectory from unstable state to steady state. Based on the Lyapunov stability theory of the controller, the effectiveness of the control scheme is proved. Finally, in the Matlab/Simulink environment, a comparative simulation with the existing linear synovial film and non-singular fast terminal sliding mode is carried out, and the designed control method realizes high-precision fast tracking of the desired trajectory of the end grab under the uncertainty of modeling error, external interference and joint friction, which verifies the effectiveness and feasibility of the proposed control method.
Research on Path Tracking Control of Driverless Trucks
Authors: Song Wei , Min Junying , Zhang Tao , Zhang Yong , Zhao Fengkui
Published: June 2024

Path tracking is a crucial function for achieving unmanned driving. This paper addresses the challenge of low tracking accuracy and poor stability in driverless trucks caused by uncertain model parameters and steady-state errors during path tracking. A linear quadratic regulator (LQR) controller optimization by an improved genetic algorithm has been designed. Firstly, the paper formulates the dynamic model of a two-degree-of-freedom vehicle as well as the model for tracking error. Subsequently, path tracking control is achieved through the utilization of feedforward control and LQR feedback control algorithms. Secondly, the weight coefficient of the LQR controller is enhanced through the utilization of an improved GA in order to boost the precision of path tracking. Ultimately, the devised controller undergoes simulation and validation in the TruckSim-Matlab/Simulink platform across diverse operational circumstances. The findings from the simulation demonstrate that the controller, optimized through improvements in the genetic algorithm, exhibits excellent tracking accuracy and stability.
Prediction of Mechanical Properties and Analysis of Damage Evolution of Fiber Bundles in Carbon Fiber Reinforced Composite Materials
Authors: Guo Rongjiao , Yan Renjun
Published: June 2024

Fiber bundles are an important component of woven composite materials, and predicting the mechanical properties of fiber bundles can provide a basis for the study of the mechanical properties of woven composite materials. This paper establishes the micro representative volume element (RVE) model of composite materials, and obtains the equivalent elastic constant of yarn through the model homogenization theory and periodic boundary conditions. Strength prediction is performed through the VUMAT user subroutine of ABAQUS. This paper uses the maximum stress standards and Von Mises standards to predict the damage initiation of TC33 carbon fiber and epoxy resin matrix, respectively. Combined with the constant degradation method, the simulation of the damage behaviors of the micro model is achieved, and the equivalent strength of the fiber bundle is obtained. The effectiveness and correctness of this method are verified by comparing the numerical model results with the Chamis theoretical model results. The accurate prediction of mechanical properties and damage process of fiber bundles provides theoretical support for the analysis of mechanical properties of composites, and has guiding significance for the performance design of composite materials.
An Efficient Strategy for Creep-Fatigue Assessment of Pipelines with Complex Local Structures and High Computational Demands
Authors: Han Mingda , Liu Hetong , Tang Yujian , Zhang Yibo , Zhang Weixu
Published: June 2024

Thermal pipelines are extensively utilized in power plants, and they operate in high-temperature and high-pressure environments. Consequently, creep and fatigue are two crucial factors that need to be considered in the design and operation of main pipelines. Assessing the safety of main pipelines considering creep-fatigue is of paramount importance. However, the current assessment of main pipelines faces challenges such as large computational requirements and susceptibility to complex local structures, making efficient evaluation a longstanding problem. Furthermore, there is a lack of commercially available software capable of automating the creep-fatigue assessment for structurally discontinuous pipelines. To address these issues, this paper proposes an efficient strategy for evaluating creep-fatigue in pipelines with complex local structures and significant computational requirements. By approximating non-critical irregular pipelines with equivalent stiffness of regular pipelines, computational accuracy and efficiency are improved. The proposed approach also enables the identification of critical locations prone to creep-fatigue. Additionally, a post-processing software based on ASME standards and utilizing existing commercial finite element software has been developed to automate the assessment of main pipelines. Compared to other computational strategies, this approach significantly enhances computational efficiency.
Research on the Swing Characteristics of Lifting Load Based on the Contact Relationship Between Pulley and Wire Rope
Authors: Cao Xuyang , Xu Zhihe , Wang Siqi
Published: June 2024

In the process of lifting operations, the complex contact relationship of the rope-pulley system is inevitably related to the swing of the lifting load. However, in previous research, the quality of the pulley and wire rope is often overlooked and the wire rope is simplified as a spring. The object of this paper is to use virtual prototyping technology to establish the rope-pulley system model that the mass and contact relationship of the pulley and wire rope are considered, and to investigate the influence of the contact relationship of the rope-pulley system on the swing characteristics of the lifting load. According to the characteristics of the rope-pulley system, the matching parameters and winding ratio of the rope-pulley system are selected as the research variables. The research method of this paper is to establish three discrete system simulation models of the rope-pulley system with different winding ratio by ADAMS/Cable module. Simulation results show that as the winding ratio of the rope-pulley system increases, the swinging amplitude of the lifting load increases; and the change in wire rope diameter has a more obvious effect on the sway of the lifting load than the change in the angle of pulley groove. The results of the study can provide a certain reference for the study on the swing of lifting loads with the rope-pulley system.
Moment-Frequency Characteristics of Limited-Angle Torque Motors for Direct-Drive Servo Rotary Valve
Authors: Shan Junfeng , Shi Youcheng , Ji Hong , Cao Shengbing , Li Zheng , Zhang Hucheng
Published: June 2024

Direct-drive rotary valve (DDRV) is directly driven by a limited-angle torque motor (LATM), which is characterized by anti-pollution, high efficiency and high frequency response. A LATM is designed for the DDRV. The main dimensions and electromagnetic parameters of the motor are calculated by analytical expression of electromagnetic torque. The torque–angle characteristics and torque characteristics of LATM were analyzed by using finite element method for ensure that the motor can have stable torque output in a wide range of turning angle, the results of theoretical and simulation agree well. On the basis, the motor was improved. The results show that the motor has a working angle of ≥±20°, the torque fluctuation within the working angle is less than 5%, and is suitable for driving the DDRV.
Simulation Research on Cutting of Shield Machine Cutter Tool Based on Anisotropic Composite Materials
Authors: Wang Qiuping , Li Wanli , Wang Daozhi
Published: June 2024

In order to study the cutting force and variation of anisotropic composite materials such as plastic vertical drainage board left in soft soil foundation by the cutter on the cutterhead of shield machine. Finite element model of orthogonal cutting theory based on macroscopic anisotropic composite materials was established by numerical simulation. Based on the above model, the finite element analysis software LS-DYNA was used to numerically simulate the cutting of plastic vertical drainage board by shield machine cutter in a project in Singapore. Meanwhile, the single cutter test device and triaxial force sensor were used to build a test platform to focus on the cutting ability test of the cutting tool on the plastic vertical drainage board under the cutting conditions of 0° and 90°. The validity and rationality of the simulation model are verified by comparing the simulated cutting force value with the experimental value. The results show that the cutting process of the plastic vertical drainage board is from the notch generation to the notch expansion and then to the final breaking process. So it can be concluded that the sharp-edge cutter is more suitable for the cutting of the plastic vertical drainage board. In the actual construction, ensuring the wear resistance and impact resistance of the sharp-edge cutter is the key to improve the service life. Sponsored by Shanghai Rising-Star Program (22QB1401900).
Study on Wind-Induced Response and Wind Vibration Coefficient of Tower Crane Under Different Wind Speed Spectra Excitation
Authors: Wang Xiangxiang , Zhang Hongsheng , Liu Wenwu
Published: June 2024

The wind-induced response and wind vibration coefficient of tower cranes under different wind speed spectra and wind direction angles are investigated to reveal the influence of wind speed distribution on the wind vibration characteristics of tower cranes. Firstly, the theoretical formula for the wind vibration coefficient based on random vibration theory is derived. Then, the APDL modeling method establishes a parametric finite element analysis model with the QTZ25 tower crane as a research object, and wind speed time history at various heights is simulated using the harmonic synthesis method. Finally, the wind speed is converted into wind loads, and the finite element model of the QTZ25 crane is subjected to random vibration analysis and spectra analysis under wind loads. The displacement time history response and displacement power spectral density at different heights are obtained, and the wind vibration coefficients are derived accordingly. The analysis results show that the wind vibration coefficient in descending order is Simiu, Davenport, and Harris wind speed spectra excitation (WSSE), respectively. The maximum deviation of the wind vibration coefficient is 12.01% at 26.09 m height with a 45° wind direction angle. In contrast, the maximum deviation of the wind vibration coefficient is 18.57% at the same height with a 0° wind direction angle. This study demonstrates that the wind-induced response of the QTZ25 tower crane remained the same under different wind speed spectra. Meanwhile, the wind vibration coefficient varied for different heights and wind direction angles, and the wind vibration coefficient was higher under Simiu WSSE and lower under Harris WSSE.
Research Progress of Remanufacturing Technology in the Field of Construction Machinery
Authors: Wang Kaiming , Liu Wei , Pang Xiaotong , Hu Yongle , Tong Yonggang
Published: June 2024

Excavator bucket teeth are often in direct contact with abrasive particles in the soil during work, resulting in the tip being severely worn. This study used laser cladding to synthesize (Ti, Nb)C reinforced coatings on the surface of Q550 steel of bucket teeth of commonly used excavators to improve the wear resistance, and researches the effects of different Ti, Nb, Cr3C2 powder ratios on the hardness, wear resistance, and wear loss of laser cladding (Ti, Nb)C reinforced coatings. The results show that the optimal powder ratio is 80% Ni-based + 1.26% Ti + 7.54% Nb + 11.2% Cr3C2. Under the optimal powder ratio, the hardness of the coating is 213.4 HV, the wear amount is 32.7 mg, and the wear failure form is abrasive wear and slight adhesive wear.
A Fast Vision-Based Algorithm for Automated Container Pose Measurement System
Authors: Zhang Yujie , Mi Chao
Published: June 2024

Addressing the current issues of low accuracy in container positioning and posture recognition, as well as long response times during the port automation loading and unloading process, this paper designs a rapid container target recognition and measurement device and method for automated loading and unloading, thereby optimizing the acquisition of key parameters in automated loading and unloading operations. This method combines advanced convolutional neural networks and traditional image processing algorithms to achieve precise detection and tracking of container corner fittings. Furthermore, this paper proposes a high-speed response method for small target measurement, which integrates minimized deep learning network technology and fuzzy image morphology matching algorithms to enhance the accuracy and stability of corner fitting detection. Through experimental verification, this method effectively improves the speed of single detection and reduces the localization error of small targets.
The Relationship Between “Nominal Pressure” and Pressure Terms Related to Lightweight Design and Manufacture of Hydraulic Cylinders
Authors: Liu Yao , Zhao Jingyi , Guo Rui , Tang Yingda
Published: June 2024

Lightweight design and manufacture of hydraulic cylinders is receiving increasing attention in construction machinery and vehicle engineering. Hydraulic cylinders, designed based on some current standards such as JB/T 10205-2010 hydraulic cylinder, have a common issue that they need to be built with a large size. This “thick and heavy” is not conducive to improving equipment performance and achieving energy conservation and emission reduction. This paper identified the root causes leading to that issue and managed to make clear the interrelation between terms used in the “nominal pressure” system and the lightweight design and manufacturing method of hydraulic cylinders. A set of novel specifications to design and test hydraulic cylinders have also been proposed which adopts the “rated pressure” as the base parameter, after referring to some related standards. Furthermore, this approach would solve the lightweight problem of hydraulic cylinder manufacturing and lay a reliable foundation for the promotion of hydraulic cylinder technology in China.
Comparative Analysis of Mathematical Models of Hydro-pneumatic Suspension Damping
Authors: Li Zeguang , Li Laiping , Huang Wei
Published: June 2024

At present, for the study of the dynamic characteristics of the hydro-pneumatic suspension of vehicles, the elastic force is mainly modeled by the variable gas equation of state, and the damping force is modeled by thin-walled orifice theory, which only considers the turbulent flow. Here, based on expressing the whole flow field including laminar flow, transition flow, and turbulence with piecewise function, the turbulence region is modeled by the Brasius formula and thin-walled orifice theory respectively. By applying vibration signals collected from real roads, the responses of two piecewise function damping force models and traditional thin-walled orifice model of 1/4 suspension system in the time domain and frequency domain respectively are calculated. The average absolute error MAE and root mean square error RSME are used to compare them with the real upper fulcrum data of the suspension cylinder. The results show that different models can simulate suspension vibration well in the low-frequency range, but there are obvious deficiencies in the middle and high-frequency range, while the short-hole flow theoretical model in the form of a piecewise function is closer to the real value in the frequency domain.
Plastic Constitutive Relation for Improving the Calculation Accuracy of Mechanical Performance of Die-Cast Al-Si Aluminium Alloy Products
Authors: Wang Xueqiang , Peng Liming , Li Siping
Published: June 2024

With the interaction in automobile manufacturing technology, products made of integrated die-cast aluminum alloy are becoming more and more widespread. However, engineers frequently ignore the impact of structural features on mechanical properties when utilizing simulation software to determine a product's strength, and current constitutive models do not account for structural flaw studies. To examine the correlation between structural flaws and mechanical properties of the die-cast aluminum alloy, quasi-static tensile tests were performed on JDA1b alloy specimens. The defect rates were varied by adding circular holes with varying diameters at the center of the specimens. The results showed that the JDA1b alloy’s tensile strength and elongation significantly decreased as the fault rate increased. A constitutive model with defect rates is proposed, which has higher accuracy than the J–C model. Simulations and experimental findings effectively validated the accuracy of the proposed constitutive model. The proposed model provides support for high-precision computing for analyzing the mechanical performance of materials.
High Temperature Creep Property of Nanoparticle Reinforced Composite by Discrete Dislocation Dynamic Method
Authors: Wang Jian , Zhang Zhengwei , Zhang Kai , Zhang Hua
Published: June 2024

Metal-matrix composites (MMCs) reinforced by nanoparticles exert much fine mechanical performance such as high strength, high modulus and good conductivities. The creep property of nanoparticle reinforced MMCs is investigated by discrete dislocation dynamic (DDD) method in this study. Both motions of dislocation glide and climb are involved in the present scheme and a dual time step strategy is adopted to deal with the velocity gap between dislocation glide and climb. The results reveal a transition of creep mechanism as the creep stress increases, and a negative correlation between the threshold stress and the environmental temperature.
Research on Path Planning of Concrete Pouring Construction Robot Based on Online Obstacle Avoidance Algorithm
Authors: Fan Siwen , Li Wanli , Yin Ruihao
Published: June 2024

Aiming at the problem of harsh concrete construction environment and low level automation of concrete pouring operation, this paper proposes an autonomous concrete pouring planning method based on real-time obstacle avoidance algorithm. A new 3-DoF articulated concrete pouring robot is designed and kinematically modeled. Rectangular fitting is adopted to simplify irregular obstacles. Then generate obstacle maps and apply intelligent obstacle avoidance algorithms based on the maps, which adopt the reward mechanism in reinforcement learning. The effectiveness of the proposed method in autonomous obstacle avoidance path planning for pouring robots is demonstrated through simulation and prototype experiments.
Customer Needs Assessment and Screening for Transmission Solution Selection
Authors: Wang Hegen
Published: June 2024

When selecting technology for transmission in the process of product development and design, various methods available for choose ideal solution from many different technical alternatives. However, this does not guarantee that a very good developed product will achieve ideal market result. This is often because there is a difference between the functionalities provided by the product and the actual customer demands. This article explores the use of the KANO model to analyze customer requirements in the early stages of product development. By categorizing customer needs and selecting the ideal solution based on different categories of customer needs, it ensures that the product development aligns with customer demands.
Study on Intelligent Driving School Vehicle System Based on Digital Twin Technology
Authors: Zhang Xinran , Bian Yongming , Yang Meng , Shao Jie
Published: June 2024

The development of intelligent vehicle systems has progressed through multiple stages, evolving from initial basic functionalities to the integration of intelligent and automated technologies, achieving significant advancements. With technological advancements, intelligent vehicle systems have gradually introduced driving assistance features such as autonomous driving assistance and adaptive cruise control. In response to the developmental needs of intelligent driving school vehicle systems, a comprehensive research proposal is presented based on digital twin technology. By incorporating a multi-source data acquisition module, real-time collection and monitoring of various sensor data within the driving school vehicles are achieved, ensuring the acquisition of crucial information during the driving process. To facilitate efficient communication between the data monitoring center and the driving school vehicles, a driving school local area network is established, providing a solid foundation for data transmission and real-time monitoring. A user-friendly and intuitive front-end interface is designed to visualize vehicle status information and student driving data for instructors, enhancing the efficiency and effectiveness of driving school education. Finally, based on practical application tests, data processing of coordinate information is conducted and showcased in the front-end interface, validating the feasibility and practicality of the designed system in driving school vehicle management and educational training.
Research on Architecture of Intelligent Simulation System for Automatic Quay Crane Training Based on Embedded Digital Twin Technology
Authors: He Mengjie , Zhang Yujie , Shen Yang , Mi Chao
Published: June 2024

The training of automated container gantry crane drivers faces with challenges, such as high safety risks, difficult training, and high learning cost. Therefore, we have designed an intelligent simulation system architecture for automated container quay cranes training based on embedded digital twin technology. This system can be directly embedded into the real quay crane remote control console without changing the original quay crane hardware equipment. It enables real-time switching between virtual quay crane remote control operation simulations and real gantry crane remote control operation, providing training for quay bridge drivers while also accounting for the real quay crane operation in time. To achieve seamless switching between real control and simulation training, we have designed two types of controllers: an automatic quay bridge remote control operation simulation system based on OPC UA communication protocol, and a real quay crane automation controller based on PLC control bus. Both controllers can communicate bidirectionally with the remote control room operating station PLC. Practical application at a wharf has demonstrated that our designed system offers high safety, real operation experience, and significant training effectiveness, effectively improving automated quay crane training outcomes, efficiency, and effectiveness.
Recognition Method for Train Coupler Handle Based on YOLOv5 Model
Authors: Liu Zhiyuan , Li Yan , Xu Zhanmou , Li Jialu , Ding Jiayi , Zhang Xiong , Wan Shuting , Zhao Jingyi , Guo Rui , Cai Wei
Published: June 2024

To solve the problem of identifying different types of car couplers during the operation of the automatic uncoupling robot of a tippler, a method for recognizing the handle of a car coupler based on the YOLOv5 model has been proposed. This method selects YOLOv5n, which is relatively simple in the YOLOv5 series, as the benchmark model for the detection network. The overall structure is more concise, effectively reducing the number of model parameters while ensuring detection accuracy. The YOLOv5n model used for feature extraction and target recognition on two types of coupler datasets: upper action and lower action, greatly reducing the time required for training and testing, and achieving extremely high recognition accuracy. Compared with the commonly used SSD300 model and Faster R-CNN model, it shows significant advantages in terms of parameter quantity, computational complexity, predictive inference speed and weight file size.
Numerical Study of Heat Transfer Effects on Non-Newtonian Nanofluid Flow Between Two Parallel Plates in the Presence of Darcy Brinkman Forchheimer
Authors: Bashir Muhammad , Abbas Munawwar Ali , Sun Bo , Chen Li , Muhammad Saima
Published: June 2024

Due to its vast industrial applications and biological context, the investigation of the inconsistent heat and mass transfer that drives the flow of squeezing viscous nanofluids between two plates is a fascinating topic. In this study, we investigated the heat transfer analysis of unsteady viscous nanofluid between two parallel plates. The partial differential equations illustrating the flow model are converted to nonlinear ordinary differential equations by suggesting similarity transformations. The resulting dimensionless and nonlinear ODEs of temperature functions and velocity are solved using the well know numerical technique shooting method by transforming the problem into initial value problem from boundary value problem. The results found are consistent with this numerical solution. Graphically explore the impacts of different parameters on temperature profiles and velocity. The results are compared with the results solved by HPM. The results concurred with this numerical solution. These findings are considered much be useful in the application of polymer processing, power transmission, compression, temporary loading of mechanical parts, food processing, cooling water, gravity machinery, modeling of plastic transport in vivo, chemical processing instruments, and demolition due to freezing.
The Perfect Fluid Characteristic of the Quark Gluon Plasma
Authors: Li Ke , Ma Cheng , Qu Jiahua , Zhang Jiayi
Published: June 2024

This article explores the unique characteristics of the Quark Gluon Plasma (QGP) by analyzing open data obtained from the ALICE experiment for Pb–Pb collisions and from the CMS experiment for Xe–Xe collisions at the Large Hadron Collider (LHC). The total integrated luminosity of the analyzed data is 3.42 $$\mu {b}^{-1}$$

μ

b

-
1

. The findings indicate that there are similar patterns in the correlation between the transverse momentum ($${P}_{t}$$

P
t

) and the flow coefficients ($${v}_{2}$$

v
2

and $${v}_{3}$$

v
3

) in both Xe–Xe and Pb–Pb collisions. Additionally, the paper estimates the shear viscosity to entropy density ratios of the QGPs by comparing the $${P}_{t}$$

P
t

dependence of $${v}_{2}$$

v
2

and $${v}_{3}$$

v
3

, as obtained from the experiments, with the calculations derived from relativistic hydrodynamics equations using various shear viscosity to entropy density ratios.
Thermal Error Modeling Method of Machining Center Linear Axis for Heat Conduction Mechanism
Authors: Ding Qiangqiang , Guo Shijie , Chen Geng , Tang Shufeng
Published: June 2024

To address the thermal deformation of machine tool components, a thermal error prediction model based on the ROA-LSSVM network was proposed. First of all, the heat transfer mechanism of the linear feed system was analyzed. By analyzing temperature distribution characteristics during the heat transfer process, the best temperature measurement point position was determined to ensure that the thermal error could be accurately predicted. Secondly, in order to build a prediction model with high accuracy and strong robustness, Raccoon optimization algorithm (ROA) was proposed to optimize the hyperparameters of the least square support vector machine (LSSVM) network model, which was difficult to determine the kernel function and penalty function. Finally, the experiment was measured on a VDL-600A machining center, and the accuracy and practicability of the proposed thermal error prediction model were verified by the thermal deformation in the measurement process. The experimental results show that The ROA-LSSVM model reduces the RMSE by 42% compared with the LSSVM network and 45% compared with the SVM network.
Model-independent estimates for loop-induced baryon-number-violating nucleon decays
Authors: Gargalionis John , Herrero-García Juan , Schmidt Michael A.
Published: June 2024

Abstract

Baryon number is an accidental symmetry of the Standard Model (SM) Lagrangian that so far has been measured to be exactly preserved, although it is expected to be violated at higher energies. In this work we compute order-of-magnitude estimates for the matching contributions of generic ultraviolet models to effective operators that generate nucleon decay processes. This is done in a systematic and automated way using operators constructed from SM fields up to dimension nine and working in a framework that has proved useful in the study of lepton-number violation. For each of the operators we derive estimates for the rates of different nucleon-decay channels. These allow us to establish model-independent lower bounds on the underlying new-physics scale and identify potential correlations between the various decay modes. The results are most relevant for families of models that generate the considered operator. This analysis is especially timely given the expected future sensitivities in numerous experiments such as Hyper-K, DUNE, JUNO and THEIA.