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The emergence of greenwashing and corporate defaults is harming the effectiveness of green credit implementation, leading to a gradual increase in regulatory pressure on banks. The widespread use of blockchain technology in the financial sector provides banks with regulatory transparency. Blockchain will be introduced into the evolutionary game in this paper to analyze the behavioral choices of banks and firms regarding green credit and to discuss in depth the impact of blockchain-related and internal parameters through numerical simulations. The study shows that (1) blockchain penalties are more significant disincentives to enterprise default or greenwash, while banks are more sensitive to changes in blockchain costs; (2) greenwashing can lead to excessive losses or high regulatory costs for banks, increasing the likelihood that the game system will evolve toward an ideal state (keep, on the chain); (3) there is a threshold for green credit lines that can reduce greenwashing and increase the incentive for banks to adopt blockchain regulation, while exceeding this threshold leads to greenwashing or defaults and banks opting for traditional regulation. This paper puts forward corresponding suggestions from the blockchain technology application, government, and social levels to provide reference significance for the effective realization of green credit regulation. [ABSTRACT FROM AUTHOR]

Assembly Workshops with Island Layout (AWIL) possess flexible production capabilities that realize product diversification. To cope with the complex scheduling challenges in flexible workshops, improve resource utilization, reduce waste, and enhance production efficiency, this paper proposes a production scheduling method for flexible assembly workshops with an island layout based on digital twin technology. A digital twin model of the workshop is established according to production demands to simulate scheduling operations and deal with complex scheduling issues. A workshop monitoring system is developed to quickly identify abnormal events. By employing an event-driven rolling-window rescheduling technique, a dynamic scheduling service system is constructed. The rolling window decomposes scheduling problems into consecutive static scheduling intervals based on abnormal events, and a genetic algorithm is used to optimize each interval in real time. This approach provides accurate, real-time scheduling decisions to manage disturbances in workshop production, which can enhance flexibility in the production process, and allows rapid adjustments to production plans. Therefore, the digital twin system improves the sustainability of the production system, which will provide a theoretical research foundation for the real-time and unmanned production scheduling process, thereby achieving sustainable development of production. [ABSTRACT FROM AUTHOR]

It's important to improve the sealing performance of the inner packer in deepwater pipelines, which is an emergency sealing and oil control equipment. The deformation characteristics and sealing stress conditions of the packer's sealant cylinder are analyzed, and the hyperelastic constitutive model is determined based on uniaxial tensile experiments. The effective contact stress and effective contact range between the rubber cylinder and the pipe wall are the main parameters for evaluating the sealing performance. Through simulation, it was found that the rubber cylinder on the force application side plays a major sealing role, and severe stress can lead to shoulder protrusions. The location of fatigue damage on the rubber cylinder's shoulder is consistent with the sea trial. Therefore, special-shaped rubber cylinders with different structures are designed to address the shoulder protrusion. The simulation shows that the sealing performance of the right-angled trapezoidal double-layer rubber cylinder with force applied on the slope side(S-RARC) is significantly better than the original rubber cylinder(ORC), and it does not produce shoulder protrusions. [ABSTRACT FROM AUTHOR]

The ultrasonic rolling processing technology has been shown to significantly reduce surface roughness and enhance the residual stress of parts, thereby improving their surface properties and extending their service life. This technology is particularly effective for the precision machining and surface strengthening of ultra-high-strength steel 42CrMo. This study aims to investigate the impact of turning pre-processing on the distribution of residual stress during ultrasonic rolling, a simulation model incorporating turning pre-processing was developed and used to conduct ultrasonic rolling simulation experiments, enabling the analysis of residual stress distribution patterns. Concurrently, ultrasonic rolling strengthening experiments were performed to validate the accuracy of the simulation model. The results confirm that with increasing rotational speed and feed rate, residual stress decreases, whereas with increasing static pressure and amplitude, residual stress increases. The residual stress variation obtained from the simulation of combined turning and ultrasonic rolling closely matched the results of experimental ultrasonic rolling tests. This consistency validates the accuracy of the simulation model. This study offers a novel approach for simulating and experimentally validating ultrasonic rolling processes, particularly for shaft-like parts that undergo turning as a pre-processing step. [ABSTRACT FROM AUTHOR]

Plastic film mulching technology can effectively enhance crop yield and quality, and the use of mulch has been increasing in recent years; however, the problem of mulch residue is worsening due to the large amount of recycling work and slow natural degradation. In this study, a potato seedling killing and residual film recycling machine is designed to provide good working conditions for potato harvesters before harvesting in response to the problems of difficult separation of film tangles, the low net rate of recycling due to the mixing of residual film with soil, and the high soil content in residual film recycling operations in northwest China. The machine is based on the potato monoculture and double row planting mode in Gansu area. This paper puts forward the overall design scheme and carries out the theoretical analysis and parameter determination of the key components, such as the seedling killing device, the film surface cleaning device, the film unloading device, and so on. Using EDEM software to carry out the virtual simulation test and Design-Expert13 to analyze the test results, we determined the optimal working scheme for the machine, with a forward speed of 0.8 m/s, a film gap of 125 mm, and a spiral stirrer speed of 600 r/min. Based on a field test for verification, the test results show that the machine's residual film recovery rate was 83.3%, the impurity rate was 3.8%, and the rate of injury to the potatoes was 1.4%. The machine meets the requirements of national and industry standards, and it can simultaneously realize straw crushing, film surface cleaning, residual film recycling, and hydraulic film unloading operations, with better operating results and while reaching the expected results. It can also provide a reference for the design and testing of a seeding and residual film recycling machine. [ABSTRACT FROM AUTHOR]

This paper presents the design and validation of a high-precision angular vibration calibration system based on a laser vibrometer, aimed at meeting the high-precision requirements for measuring small angular vibrations. The system primarily consists of a self-driving angular vibration platform and a laser vibrometer. The platform is isolated from ground interference via an air-floating platform and uses a split-type motor to control the platform, generating specific angular vibrations. Detailed simulations of the platform's modal characteristics and the stability of the spring plates were conducted using the finite element analysis software ANSYS 11. Moreover, fundamental frequency testing and measurement accuracy testing were conducted on the system. Experimental results demonstrate that the system has a fundamental frequency of 2.69 Hz and a maximum measurement error of 0.00172″, confirming the system's effectiveness in dynamic characteristics, stability, and measurement accuracy. This research provides essential technical support for high-precision angular vibration control in spacecraft. [ABSTRACT FROM AUTHOR]

The efficient operation of electronic cards, which are used as a subcomponent in many products such as telephones, televisions, computers, automobiles and smart devices, depends on appropriate design, production and quality. High product variety in production processes, production capacity constraints and setup times in model changes can result in non-value-added intermediate operations and lead times, resulting in inefficiency. This study proposes an effective approach to the line assignment problem for electronic board production addressing efficiency increase and cost reduction. The resulting production plan, which will provide the highest production amount of electronic cards in different assembly and testing lines, considers different characteristics of electronic cards (e.g., bill of materials, common component use, number of components, demand, operation times and process flow). The PCB line assignment problem, which is in the NP-hard problem class, was solved by clustering analysis and a 0-1 mixed integer mathematical model. The results of the model were analyzed with a simulation model that models the operation of the production line. In the application made with real data, 22% improvement was achieved in the production amount compared to the current situation by using the proposed approach. The proposed approach can be applied to the scheduling of an electronic board manufacturer with multiple surface mount technology (SMT) assembly lines, multiple process flows, and multiple testing stations. [ABSTRACT FROM AUTHOR]

Copyright of China Petroleum Machinery is the property of China Petroleum Machinery Editorial Department 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.)

Management factors are among the most significant causes of construction safety incidents, and there is an issue of insufficient supervision at present. The degree of diligence exhibited by relevant entities is crucial, and the payoff can influence the decision-making behaviors of involved parties. Based on this, the aim of this paper is to investigate how to enhance the initiative of enterprises in fulfilling their safety responsibilities during the construction process. By developing a tripartite evolutionary game model that involves supervision companies, general contractors, and labor subcontractors and conducting numerical simulation analysis, we reveal that simultaneous proactive investment in safety by all three parties is challenging, with labor subcontractors being relatively more prone to opt for active safety investment. Supervision companies and general contractors often struggle to fulfill their safety duties at the same time. Factors such as the rewards and penalties stipulated in a contract, rent-seeking amounts, and accident-related losses have a significant impact on the evolution of the system. Based on the findings, we propose recommendations for construction management, which include the management of labor subcontracting in construction, the control of rent-seeking behaviors, and the establishment of a cooperative safety culture during the construction process. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management 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.)

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management 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.)

The objective of the kinematic model of rock chips is to examine the impact of the driving parameters of drilling tools on the effective chip removal speed, with a view to analyze the chip removal performance of rotary percussion ultrasonic drilling. The discrete element numerical simulation method, EDEM-2022 simulation software, was employed to establish a simulation model, match the simulation parameters, and conduct a simulation study of chip removal under the action of rotary percussion. This was performed to analyze the influence of the driving parameters on the chip conveying process. In order to ascertain the order of parameters affecting the degree of conveyance rate as well as the optimal driving parameters, orthogonal experiments were designed based on Taguchi's experimental analysis method. [ABSTRACT FROM AUTHOR]

Aiming at the problems of low efficiency and poor cleaning quality in the cleaning process of harvested tiger nuts (Cyperus esculentus) with lots of soil and fibrous roots on the surface to meet the demand for mechanized harvesting of tiger nuts in the Yellow River, Huaihe River, and Haihe River regions in China, a pulsating roll-cleaning device was devised. The analytical software for meshing the transmission of pitch curves of elliptical gears with arbitrary orders was developed based on Visual Basic 6.0, thus obtaining a pair of elliptical gears that meet the steady transmission requirement. The meshing of this pair of elliptical gears enables pulsating variable-speed rotation of a brush roller, which reduces the breakage and accumulation of tiger nuts. Circular screen holes are distributed uniformly on the upper and lower cylindrical walls. Tiger nuts are cleaned under friction with the brush roller and the circular screen holes, while residues (including soil) fall in the settlement and accumulation tank through the screen holes, which realizes the rapid discharge and collection of residues, including soil, and reduction of dust. The separation process of soil from tiger nuts in the cleaning device was studied using RecurDyn 2023-EDEM 2022 simulation software. Taking the rate of rotation of the brush roller, order of elliptical gears, and eccentricity of the elliptical gears as the test factors while taking the cleaning efficiency, breakage rate, and impurity rate as the evaluation indices, a test bench for the cleaning performance of tiger nuts was established. Design-Expert V8.0.6 was applied to carry out a three-factor three-level Box–Behnken design (BBD) using response surface methodology (RSM), thus ascertaining the optimal parameter combination of the cleaning device. When the rate of rotation of the brush roller, order of elliptical gears, and eccentricity of the elliptical gears are, separately, 280 rpm, 2, and 0.122, the cleaning efficiency, breakage rate, and impurity rate of tiger nuts are 1.83 t·h−1, 0.15%, and 0.16%, respectively. This satisfies the cleaning requirement of tiger nuts and provides a basis for the design of cleaning machines for tiger nuts. [ABSTRACT FROM AUTHOR]

In the context of locomotive traction systems, the power electronic traction transformer (PETT) represents a pivotal component, fulfilling essential functions pertaining to electrical isolation and power control. The majority of existing PETT prototypes employ a combination of a cascade structure and an ISOP structure. The aforementioned scheme effectively reduces the voltage withstand level of the power devices on the input side, yet it also necessitates the utilisation of a greater number of power devices and passive components within the PETT. In order to further reduce the number of power devices used, this paper proposes a new cascaded PETT design. The proposed PETT will adopt a scheme combining a cascade structure and a hardware circuit multiplexing. This paper first analyses the operation principle of the new circuit under non-single frequency PWM control. It then derives the design equations for some hardware parameters and control circuits. Finally, it verifies the effectiveness of the proposed PETT through simulation analysis. [ABSTRACT FROM AUTHOR]

There are a series of problems in the maintenance of transmission towers. In this paper, based on the existing structure, a climbing robot that can be applied to the transmission tower is designed, and the reliability of the grasp is analyzed. Key parts are optimized with Ansys analysis software and planning for climbing gait is completed with Adams simulation software; Robot control system is designed based on hierarchical and decentralized control architecture and the paw position adjustment decisions are optimized, and the fuzzy control algorithm is used to realize the gait adjustment of the robot The experiment result shows, the robot can complete the task of climbing and crossing the obstacle of the steel surface of the tower angle. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

Rotate vector (RV) reducers are the two-stage deceleration device comprising involute and cycloid-pin gear transmission mechanisms. As the typical deceleration elements, they are widely applied in industrial robots, digitally controlled machine tools and automation fields due to their compact structure and high precision. However, a reducer may lose precision after a long-term operation. Moreover, pitting and metal peeling of internal components may also occur, leading to a fatigue failure. Therefore, it is necessary to conduct investigations on lifespan evaluation for RV reducers. In this study, the CRV-80E reducer is taken as the research object. Firstly, according to its transmission characteristics, the lifespan evaluation model for a standard RV reducer is established based on fatigue strength theory and Palmgren-Miner linear cumulative damage law, with the internal crankshaft bearing is considered as the key component. Then, the simulations are carried out on crankshaft bearing by the ANSYS Workbench and SKF SimPro. The contact stress, deformation on bearing rollers, and the rated lifespan of the reducer are simulated. Finally, the accelerated life test is conducted on an RV reducer by increasing the external load with the positioning precision as an output and criterion. After the test, the reducer is disassembled, and metal peeling failure is observed on the crankshaft bearing while other parts are relatively intact. The test results validate the feasibility and accuracy of the service life evaluation model and simulation analysis. This study provides a new research approach for researchers and manufacturers and a design reference for engineers to improve the lifespan of RV reducers by optimizing crankshaft bearings, which have a certain academic value. [ABSTRACT FROM AUTHOR]

To enhance the reliability of mine mechanical and electrical systems, promptly detect and prevent potential failures, improve mining production efficiency, ensure worker safety, and maintain normal equipment operation, a fault information data diagnostic system was established to collect fault data from mine mechanical and electrical systems. A Bayesian fault network was constructed and converted into a binary decision diagram using the ITE structure for qualitative and quantitative analysis of system faults. The results show that the constructed model achieved a diagnostic accuracy rate of over 98% across different mining software platforms. In an actual evaluation of a mine mechanical and electrical system, insulation aging or damage, overload or overheating, electronic component failures, and internal short circuits were found to have the highest impact on fault, approximately 0. 972. This significantly improved the accuracy and efficiency of fault diagnosis in mechanical and electrical systems and provided an effective assessment of underlying fault nodes. The findings can serve as a reference for fault diagnosis and reliability assessment in similar mechanical and electrical systems. [ABSTRACT FROM AUTHOR]

The PWM voltage pulses output by the inverter reaches the stator winding of the wind turbine generator through the cable. Due to the impedance mismatch between the motor and the cable, the voltage at the motor end rises under the action of the circuit wave process; on the other hand, electromagnetic oscillation occurs within the motor winding. Higher overvoltage is generated under the combined effect of both, which greatly accelerates the aging and breakdown of the insulation layer of the permanent magnet synchronous wind turbine. In this paper, a three-dimensional electromagnetic model of the permanent magnet synchronous wind turbine generator is established. The distribution circuit parameters of the stator winding of the permanent magnet machine are calculated using the finite element method, and its circuit model is based. The voltage distribution of the stator winding under different PWM excitations is investigated by simulation software, and the effects of the time of the rising edge and the pulse width of the PWM pulse on the stator winding voltage to ground and the turn-to-turn voltage distribution are studied. The results show that the effect of the rising edge time is larger when the rising edge time is shorter, the maximum voltage to ground occurs in the first coil, and the amplitude can be up to 1.5 times of the output voltage. When the rising edge time is longer, the maximum voltage to ground occurs in the end coil, and the amplitude is slightly higher than the output voltage. The trend of turn-to-turn voltage variation is similar for different rising edges; only the maximum turn-to-turn voltage amplitude is different. Pulse width has a small effect on overvoltage and only occurs when the pulse width is less than 10 μs. The research results of this paper are of great significance in revealing the aging and breakdown mechanism of the generator stator insulation, as well as the insulation coordination and design. [ABSTRACT FROM AUTHOR]

Low-credibility gossip information in social networks is a trigger for online opinion distortion. Since fragmented information always appears along with low content credibility and gossip, this paper put forward an online opinion distortion model based on DW algorithm, and information credibility, gossip intensity and opinion leaders were integrated in order to find out the mainly factors which induce opinion distortion. Then, four groups of experiment by using MATLAB were conducted, and the results show that the credibility of information is a key factor affects the speed of opinion, and also very important for the direction of the opinion dynamic of the whole network. Online opinions can easily impact by the gossip information, and extreme gossip information causes serious division of opinion group, and the whole network opinions cannot be converged even in a quite long-time iteration. Super opinion leaders have the ability to balance the influence of gossip, even in an online environment full of gossip information. Based on these, a case study including 315 thousand records of posts and comments from Weibo is conducted for confirming the mainly findings in the simulation analysis, and strategies like high credibility information, low gossip probability, and behalf opinion leader are put forwarded finally for reduce opinion distortion. [ABSTRACT FROM AUTHOR]

Knowledge innovation is the driving force and guarantee of regional development. Inspired by population ecology, this article uses symbiosis theory to explore the symbiotic relationship of subjects in the regional knowledge innovation ecosystem. The nonlinear Lotka–Volterra model is constructed with the main subjects to measure the knowledge innovation ability of knowledge innovation subjects. The symbiotic relationships among the knowledge innovation subjects in each region are identified. Taking Beijing, Shanghai, and Guangzhou as examples, a sensitivity analysis of the initial value and coopetition relationship is conducted. The results show that the initial value change has no significant effect on the development of knowledge innovation subjects. The interaction relationships among subjects directly affect the symbiotic evolution trend. The study extends the application scope of the symbiosis theory and develops a theoretical framework for the development of subjects in regional knowledge innovation ecosystem. It offers regions a reference to use Lotka–Volterra model adjusting the knowledge innovation structure in various regions. [ABSTRACT FROM AUTHOR]

The safety status of immersed tube tunnel(ITT) joints is continuously evolving, making direct deformation sensing challenging. Therefore, a case study is conducted on the subsea ITT of the Hong Kong-Zhuhai-Macao bridge. By examining existing monitoring data, the deformation patterns of ITT joints are summarized to reveal the strong correlation between the expansion/contraction deformation of joints and structural temperature as well as the significant impact of tidal variations on the shear deformation at joints. Furthermore, a knowledge-data-driven rapid inference method is proposed for joint deformation. This method involves constructing a refined finite-element model of the tunnel, analyzing its mechanical behavior under various typical deformation modes, and generating a dataset of deformation service behaviors. By employing a back-propagation neural network, a comprehensive cross-sectional deformation inference model is developed for tunnel joints based on the simulated joint service behaviors. This enables the rapid reconstruction of joint deformations using limited actual measurement data. The proposed analytical method has been successfully applied to the on-site maintenance of the ITT of the Hong Kong-Zhuhai-Macao bridge. The case study demonstrates that during Typhoon Saola in 2023, the overall impact of the typhoon on the ITT joint system was relatively sma [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology 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.)

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology 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.)

Copyright of Chinese Medical Equipment Journal is the property of Chinese Medical Equipment Journal 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.)

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry 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.)

With technological advances and industrial upgrading, electro-mechanical actuators (EMAs) have gradually replaced traditional hydraulic actuation systems. During operation, force servo systems inevitably suffer from external force or position disturbances, thus affecting the output performance of the system. Therefore, it is of significant engineering application value to develop EMA anti-disturbance control strategies that exhibit strong robustness and are more easily applicable to engineering practice. In this study, an open-loop transfer function of the system with command signals and disturbance signals as inputs was established based on the nonlinear mathematical models built for the core components of EMAs. To overcome the impact of external position disturbances on the motion performance of the force servo system, a proportional integral derivative (PID) controller was introduced and a high-order transfer function associated with various parameters such as speed and acceleration was derived and obtained as feedforward compensation based on the mathematical model. By incorporating a three-loop PID controller, the impact of external disturbance forces on the motion performance of the position servo system was overcome and the tracking accuracy of the system was also improved. Finally, simulation models were built using AMESim software (AMESim 2020, LMS Imagine.Lab, Roanne, France) and a dual-channel EMA performance testing system was developed. Simulation and test results indicated that both anti-disturbance control methods exhibited strong robustness and excellent anti-disturbance performance, with the control accuracy and dynamic performance almost unaffected by disturbances. This verified the correctness of the single-channel EMA anti-disturbance control strategy and the usability of the simulation model. [ABSTRACT FROM AUTHOR]

In response to problems such as insufficient adhesion, difficulty in adjustment, and weak obstacle-crossing capabilities in traditional robots, an innovative design has been developed for a five-wheeled climbing robot equipped with a pendulum-style magnetic control adsorption module. This design effectively reduces the weight of the robot, and sensors on the magnetic adsorption module enable real-time monitoring of magnetic force. Intelligent control adjusts the pendulum angle to modify the magnetic force according to different wall conditions. The magnetic adsorption module, using a Halbach array, enhances the concentration effect of the magnetic field, ensuring excellent performance in high-load tasks such as building maintenance, bridge inspection, and ship cleaning. The five-wheel structural design enhances the stability and obstacle-crossing capability, making it suitable for all-terrain environments. Simulation experiments using Maxwell analyzed the effects of the magnetic gap and the angle between the adsorption module and the wall, and mechanical performance analysis confirmed the robot's ability to adhere safely and operate stably. [ABSTRACT FROM AUTHOR]

Copyright of China Forest Products Industry is the property of China Forest Products Industry 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.)

Panax notoginseng belongs to the long stemmed crop, and the harvesting of its stems and leaves is one of the important processes. Aming at the problems of high labor intensity and lack of mature harvesting equipment, based on the agronomic requirements of Panax notoginseng cultivation and the mechanical parameters of Panax notoginseng stems, a harvesting device for Panax notoginseng stems and leaves under the forest was designed, which mainly consisted of a control box, a frame, and a leaf cutting device. The overall size, cutting stroke, forward speed and cutting pair width of the device were determined, and the device structure was compacted, which met the requirement of harvesting. The design of key structural parameters for reciprocating cutters mainly included moving blade, fixed blade, crank connecting rod mechanism, blade protector, etc. The reciprocating cutter could meet the technical requirements while didn't damage seedlings and miss cutting Panax notoginseng stems and leaves. A kinematic analysis was conducted on the cutter, and it was determined that the cutting speed was 0.4~0.8 m·s-1, which ensured the cutting effect while also ensuring the stability and safety of the entire machine. A rigid flexible coupling simulation model of Panax notoginseng stem and cutting blade was constructed, and cutting blade simulation analysis was carried out with the maximum cutting force as evaluation index. Based on three factors and three levels test results, it was found that the factors affecting cutting from large to small were cutting angle, cutting speed and tool configuration. The reduction effect of blade shape on Panax notoginseng stem cutting force was determined, with triangular blade>trapezoidal blade>rectangular blade, The optimal parameter combination for the stem cutting blade of Panax notoginseng was cutting angle of 90.5°, triangular blade shape, and cutting speed of 0.52 m·s-1. At this condition, the maximum cutting force was 7.46 N, which met cutting requirements. [ABSTRACT FROM AUTHOR]

Abstract The ultrasonic rolling processing technology has been shown to significantly reduce surface roughness and enhance the residual stress of parts, thereby improving their surface properties and extending their service life. This technology is particularly effective for the precision machining and surface strengthening of ultra-high-strength steel 42CrMo. This study aims to investigate the impact of turning pre-processing on the distribution of residual stress during ultrasonic rolling, a simulation model incorporating turning pre-processing was developed and used to conduct ultrasonic rolling simulation experiments, enabling the analysis of residual stress distribution patterns. Concurrently, ultrasonic rolling strengthening experiments were performed to validate the accuracy of the simulation model. The results confirm that with increasing rotational speed and feed rate, residual stress decreases, whereas with increasing static pressure and amplitude, residual stress increases. The residual stress variation obtained from the simulation of combined turning and ultrasonic rolling closely matched the results of experimental ultrasonic rolling tests. This consistency validates the accuracy of the simulation model. This study offers a novel approach for simulating and experimentally validating ultrasonic rolling processes, particularly for shaft-like parts that undergo turning as a pre-processing step.

This paperwork explores the transshipment operations at the Port of Constanta, Romania, focusing on the unloading of big bags from barges. Utilizing Business Process Management (BPM) software, the study models the transshipment process to identify optimization opportunities. The investigation reveals challenges such as coordination complexities and potential cargo damage, alongside the benefits of cost-efficiency and flexibility offered by transshipment services. Through literature review and analysis, the study emphasizes the importance of efficient business processes and the role of BPM software in enhancing operational efficiency. By employing Aura Portal Modeller for simulation, the study identifies bottlenecks and proposes optimization strategies for the transshipment process. The proposed measures include real-time cargo assessment, inventory tracking systems, equipment analysis, and storage layout optimization. This research contributes to the understanding of transshipment operations and highlights the effectiveness of BPM software in process visualization and analysis, offering insights for enhancing efficiency and mitigating delays in supply chain management.

Magnesium alloys have received a lot of attention in aerospace, automotive, electronic communications and other fields due to their low density, high specific strength and damping performance. However, magnesium alloy sheets prepared by conventional thermomechanical processing usually have a strong basal texture, resulting in poor formability. In this paper, Mg–Mn–Ce alloys with good plastic forming ability were prepared by studying and optimizing the annealing process. Under the low-temperature annealing condition, it can promote the static recrystallization and grain refinement of Mg–Mn–Ce alloy, and also eliminate the internal stress. With the increase of annealing temperature, a large amount of dispersed Mg12Ce as a stable second phase effectively hindered the grain boundary migration, while the nanoscale α-Mn forms a fine second phase to inhibit grain growth, and both of them together greatly stabilize the deformation structure of the alloy, and maintain a good grain organization under the condition of annealing temperature of 300 °C and holding time of 30 min. The present work also improves the Arrhenius constitutive equation for the Mg–Mn–Ce alloy with respect to the degree of deviation, which significantly improves the accuracy of the model in predicting the thermoforming behavior. Meanwhile, to address the shortcomings of the traditional forming method of magnesium alloy, the processing process of spreading the centrifugal casting tube flat is proposed, the forming process is simulated, and the location of easy breakage in the forming process is predicted. These findings provide microanalytical support for the improvement of forming properties of magnesium alloys by annealing.

Multi-competitor races often feature complicated within-race strategies that are difficult to capture when training data on race outcome level data. Models which do not account for race-level strategy may suffer from confounded inferences and predictions. We develop a generative model for multi-competitor races which explicitly models race-level effects like drafting and separates strategy from competitor ability. The model allows one to simulate full races from any real or created starting position opening new avenues for attributing value to within-race actions and performing counter-factual analyses. This methodology is sufficiently general to apply to any track based multi-competitor races where both tracking data is available and competitor movement is well described by simultaneous forward and lateral movements. We apply this methodology to one-mile horse races using frame-level tracking data provided by the New York Racing Association (NYRA) and the New York Thoroughbred Horsemen's Association (NYTHA) for the Big Data Derby 2022 Kaggle Competition. We demonstrate how this model can yield new inferences, such as the estimation of horse-specific speed profiles and examples of posterior predictive counterfactual simulations to answer questions of interest such as starting lane impacts on race outcomes. [ABSTRACT FROM AUTHOR]

Abstract This study presents a major advance in grid management: the development and deployment of an integrated network command system for the main distribution network. The system integrates cutting-edge information technology, including modules such as command issuance, intelligent routing, security assurance and in-depth data analysis, opening a new era of refined and intelligent power grid management. The research focuses on the application of core technologies such as information communication technology, distributed control system, artificial intelligence and big data analysis, and strengthens the system operation foundation. The chapter on system architecture details the innovative integration of DDQN algorithm and attention mechanism, and carefully constructs intelligent scheduling engine and status monitoring and early warning system, which significantly improves real-time response, decision optimization and active security defense capabilities. Simulation experiments and actual case analysis verify the effectiveness of the system, specifically, the response time is reduced by 75.7%(from 2.1 s to 0.51 s in the traditional system), the data processing speed is still maintained at a high level under high load (100,000 data processing rate is 300/s), and the system stability is as high as 99.97%. The new system also achieved a high degree of automation, reducing annual operation and maintenance costs by 20%, and increasing user satisfaction to 90%, an increase of 28.6% over the previous period. These improvements not only optimize power quality and grid efficiency, but also further confirm that the fault response time is reduced by 30% and the user outage time is reduced by 25%. Therefore, this study not only highlights the innovation of the proposed system, but also demonstrates its significant contribution to accelerating the modernization of power grid management and ensuring safe operation with empirical data.

The end-window Geiger-Miller counter (end-window GM counter) is one of the core detectors in the field of radiation detection. End-window GM counter has many advantages such as low cost, high reliability, and strong versatility, especially in being able to measure alpha, beta, and gamma rays simultaneously, and meets various radiation measurement needs. The electric field distribution of the end-window GM counter is one of the important parameters for evaluating its working performance. The paper aims to solve the difficulty in determining core design parameters such as operating voltage and anode/cathode structure, during the development and design process of a new type of end-window GM counter. The international advanced type of end-window GM counter was took as the research object, key simulation input parameters were identified, refined electromagnetic simulation model was established, and the electric field distribution characteristics inside the counter was analyzed. Finally, the influence mechanism and pattern of the core design parameters of the counter on electric field distribution were researched. The simulation results show that parameters such as operating voltage, power supply mode, anode structure, relative position of anode and cathode, and end-window structure all have an impact on the electric field distribution in the counter. The electric field intensity in the bottom area of the counter is higher than that in the top area of the counter, and is relatively highest in the central area at the bottom, the charged particles mainly drift between the reticulated anode and the bottom surface of the counter. The electric field inside the counter is mainly distributed near the anode, which is the main area where particle multiplication effects occur. The peak electric field intensity appears at the edges of each anode ring and increases with the increase anode ring radius. The peak and mean electric field intensity inside the counter increase linearly with the operating voltage, and uniformity of the electric field is not affected. Negative power supply method can improve the dead time of the counter, but the peak and mean electric field intensity inside the counter decrease, and the uniformity deteriorates. The electric field distribution is more sensitive to thickness of the anode. The anode is more suitable to be arranged in bottom of the counter. The conductive coating can further improve working performance of the counter. The paper provides theoretical, methodological and data support for the development, optimization design, and engineering practice of new and advanced end-window GM counter, and has certain guiding significance for the simulation analysis methods of other gas radiation detectors.

With the increasing energy consumption in buildings, the proportion of energy consumption in public buildings continues to grow. As an essential component of public buildings, sports buildings are receiving more attention regarding energy-saving technologies. This paper aims to study the passive energy-saving design methods of small-and medium-sized sports halls in hot summer and cold winter regions, exploring how to reduce building energy consumption by improving the spatial design and thermal performance of the enclosure structures of sports halls. Taking the Wuhu County Sports Center as an example, this study uses computer simulation software to analyze the building’s wind environment and the thermal performance of its external walls and roof. The results show that the large volume of the sports hall significantly impacts the distribution of wind speed and pressure around it, and this impact decreases with height. The thermal simulation of the enclosure structures demonstrates that adding insulation layers to the interior and exterior of the walls and roof of the sports hall is an effective way to reduce energy consumption in both winter and summer. Additionally, wind environment simulations of different roof shapes reveal that flat roofs have the most significant blocking effect on wind and are prone to inducing strong vortices on the leeward side; concave arch roofs have the least blocking effect on airflow, and arch and wave-shaped roofs maintain lower vortex intensity on the leeward side. Hopefully, this study can provide significant references for the energy-saving design of future small- and medium-sized sports buildings.

Abstract To address the low efficiency and high labor demands of manual Codonopsis pilosula cultivation, as well as the limitations of existing flat-type transplanting machines that create trenches of inconsistent depth hindering root growth and seedling emergence, a C. pilosula film-covered outcrop tilted transplanting machine was developed. Based on theoretical analysis of the prototype's key components and agronomic requirements for oblique C. pilosula transplanting, the structure and working parameters of the rotary tiller soil throwing device, soil lifting device, track-type soil conveying device, seedling throwing device, and film covering device were determined. The core components' working principles were analyzed, and the soil throwing process of the rotary tiller device was simulated using the discrete element method (DEM). A calculation domain was established, and the results showed that the average mass of the rotary tiller device was 49.44 kg, while the required soil lifting amount for the scraper-type soil lifting device was 21.84 kg, meeting the soil throwing requirements. Field experiments in 10 test areas demonstrated an average qualified rate of 89.50% for planting depth, 84.00% for planting posture, 90% for exposed plant spacing, 4.51 cm for plant spacing, and 8.67% coefficient of variation for planting spacing. These results meet industry standards for planting depth and planting spacing, confirming the machine's effectiveness in achieving high-quality tilted transplanting of C. pilosula seedlings.

This study investigates the problem of beam deflection in curved continuous beam bridges. Taking the D0–D6 spans of the Gongbin Road viaduct as a basis, the main factors influencing the deflection of curved beam bridges are analyzed. The Midas/Civil finite element simulation software is used to calculate and analyze the causes of transverse and longitudinal deflection in curved beam bridges. The results show that the main influencing factor for beam deflection during operation is the system temperature, which causes a displacement greater than the combined displacement caused by self-weight, construction stage, gradient load, vehicle load, and bearing settlement. Damages to expansion joints during operation change the boundary conditions of the beam, preventing longitudinal free expansion under temperature load, and increasing the transverse displacement to 2–3 times the normal working state of the expansion joint, resulting in beam deflection. In the design phase, the selection of curvature radius and fixed support displacement is also a major factor affecting deflection. The smaller the curvature radius, the greater the influence on transverse and longitudinal deflection of the beam. However, when the curvature radius R is greater than 400 m, the impact on beam deflection can be neglected. The closer the fixed support position is to the ends of the bridge, the higher the possibility of bearing detachment, ultimately leading to beam deflection.

Objective As construction error of the rigid catenary at 160km /h train speed affects the dynamic performance of the pantograph catenary, the technical parameters that meet the condition for the pantograph and rigid catenary system at 160 km/h are designed based on the on-site measurement data and the simulation analysis of rigid pantograph catenary system. Method Firstly, the guiding height (vertical distance from catenary to rail surface) parameters of Guangzhou Metro Sanbei Line are measured, and the probability distribution of guiding height is analyzed. It is concluded that the guiding height distribution is basically consistent with the static height distribution of the fixed points, both following the normal distribution. Then, in consideration of the construction error of the guiding height, the DSA250 pantograph is selected and the dynamic simulation model of the pantograph is established according to TB/T 3271. Finally, the dynamic performance of the pantograph catenary under different construction errors is simulated and analyzed, and the technical parameters of the pantograph catenary system meeting 160 km/h requirements are designed. Result & Conclusion The construction error of rigid suspension device guiding height follows the probability distribution model of normal distribution. The standard deviation of the contact force with construction error is 2 to 3 times that without construction error, indicating that the construction error of the guiding height has significant influence on the dynamic coupling performance of the pantograph catenary. For the construction error of rigid suspension device guiding height, the height of 6 fixed points at the anchor segment joints strictly follows the normal distribution with the mean being the nominal height of the overhead line and the standard deviation being 2 mm, and the height of other fixed points strictly follows the normal distribution with the mean being the nominal height of the overhead line and the standard deviation being 3 mm.

Abstract Temperature and humidity variations in burial stone relics can easily cause water vapor condensation, which is an important factor leading to their deterioration. However, the water vapor condensation mechanism and the evaluation of risk ratings have always been difficult problems in the protection of cultural relics. In this study, the water vapor condensation mechanism in Yang Can's tomb was comprehensively investigated through on-site monitoring, indoor experiments and software simulations, on the basis of which a physical model of water vapor condensation in this tomb was established and a water vapor condensation risk rating assessment method was proposed. The proposed method considers the difference between the dew point and wall temperatures within the tomb (dew–wall temperature difference) and the duration of water vapor condensation, and corresponding preventive and control measures were formulated for different risk ratings. The study revealed that when the wall temperature of the chamber is lower than the dew point temperature, water vapor starts to condense. The larger the dew–wall temperature difference is, the greater the risk of condensation. In addition, specific water vapor condensation prevention and control measures were proposed for Yang Can's tomb, and the prevention and control effects were simulated. The simulation results showed that favorable prevention and control effects could be achieved, and the proposed measures could be applied in practice. This study holds notable significance for investigating the water vapor condensation mechanism and evaluating the risk ratings of burial stone relics and provides a theoretical basis and reference for water vapor condensation prevention and control in burial stone relics.

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This study presents a major advance in grid management: the development and deployment of an integrated network command system for the main distribution network. The system integrates cutting-edge information technology, including modules such as command issuance, intelligent routing, security assurance and in-depth data analysis, opening a new era of refined and intelligent power grid management. The research focuses on the application of core technologies such as information communication technology, distributed control system, artificial intelligence and big data analysis, and strengthens the system operation foundation. The chapter on system architecture details the innovative integration of DDQN algorithm and attention mechanism, and carefully constructs intelligent scheduling engine and status monitoring and early warning system, which significantly improves real-time response, decision optimization and active security defense capabilities. Simulation experiments and actual case analysis verify the effectiveness of the system, specifically, the response time is reduced by 75.7%(from 2.1 s to 0.51 s in the traditional system), the data processing speed is still maintained at a high level under high load (100,000 data processing rate is 300/s), and the system stability is as high as 99.97%. The new system also achieved a high degree of automation, reducing annual operation and maintenance costs by 20%, and increasing user satisfaction to 90%, an increase of 28.6% over the previous period. These improvements not only optimize power quality and grid efficiency, but also further confirm that the fault response time is reduced by 30% and the user outage time is reduced by 25%. Therefore, this study not only highlights the innovation of the proposed system, but also demonstrates its significant contribution to accelerating the modernization of power grid management and ensuring safe operation with empirical data. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the Osprey Optimization Algorithm (OOA) does not have high optimization accuracy and is prone to falling into local optimum, an Improved Osprey Optimization Algorithm Based on a Two-Color Complementary Mechanism for Global Optimization (IOOA) is proposed. The core of the IOOA algorithm lies in its unique two-color complementary mechanism, which significantly improves the algorithm's global search capability and optimization performance. Firstly, in the initialization stage, the population is created by combining logistic chaos mapping and the good point set method, and the population is divided into four different color groups by drawing on the four-color theory to enhance the population diversity. Secondly, a two-color complementary mechanism is introduced, where the blue population maintains the OOA core exploration strategy to ensure the stability and efficiency of the algorithm; the red population incorporates the Harris Hawk heuristic strategy in the development phase to strengthen the ability of local minima avoidance; the green group adopts the strolling and wandering strategy in the searching phase to add stochasticity and maintain the diversity; and the orange population implements the optimized spiral search and firefly perturbation strategies to deepen the exploration and effectively perturb the local optimums, respectively, to improve the overall population diversity, effectively perturbing the local optimum to improve the performance of the algorithm and the exploration ability of the solution space as a whole. Finally, to validate the performance of IOOA, classical benchmark functions and CEC2020 and CEC2022 test sets are selected for simulation, and ANOVA is used, as well as Wilcoxon and Friedman tests. The results show that IOOA significantly improves convergence accuracy and speed and demonstrates high practical value and advantages in engineering optimization applications. [ABSTRACT FROM AUTHOR]

In the developmental phase of passenger automobile hoods, it is crucial to take dent resistance and pedestrian head protection performances into account. And maintaining a performance balance between the two aspects has proven challenging. With few studies on how to effectively maintain the balance, in this paper, a certain passenger car hood was used as a basic model to investigate structural improvement directions that benefit both performances, by modifying several key variables of the honeycomb shaped inner panel one at a time and then outputting results of hood dent resistance and headform impact through Abaqus and LS-DYNA, respectively. The results indicated that raising the honeycomb inner panel structure at positions with poor stiffness contributes to improvements in dent resistance and pedestrian head protection performance, reflecting in a maximum stiffness increase of 50% and a reduction of 2.98% in the average value of HIC15 change rate. And other alternative improvement options, as well as their effects on dent resistance and pedestrian head protection performance, were provided, providing insights for optimizing the structure of vehicle hood inner panels. [ABSTRACT FROM AUTHOR]