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The purpose of this study is to systematically investigate the novel phenomenon of rail corrugation on small radius curves with rail joints in mountainous city metros, characterized by the coexistence of short and long wavelengths (30–40 mm and 150–200 mm) on the low rail.

The finite element model of the wheel-rail system in the section with rail joint is constructed based on field surveys. The friction-coupled vibration characteristics of the wheel-rail system are studied from the perspective of friction self-excited vibration of the wheel-rail system and feedback vibration of the rail irregularity.

The rail corrugation with short wavelength is primarily induced by the friction self-excited vibration of wheel-rail system. In contrast, the rail corrugation with long wavelength is predominantly caused by the feedback vibration of rail joint irregularity. Additionally, the feedback vibration of corrugated irregularity accelerates the progression of corrugation depth without triggering the emergence of rail corrugation with new wavelength.

The research advances the understanding of the vibration inducement behind rail corrugation in mountainous city metros.

Considering two types of subsidies for producers (supplier and manufacturer) and one for consumers based on product greenness and sales quantity, this study aims to formulate optimal supply chain green innovation and subsidy strategies, and to achieve this goal with the support of information systems.

This study introduces a composite green-product supply chain where suppliers focus on green innovation for component greenness and manufacturers focus on green innovation for manufacturing process greenness. Game theory modeling is applied to investigate the differences of product greenness, supply chain members’ profit and social welfare under different government subsidy strategies.

Increasing the unit greenness subsidy coefficient can boost product greenness and supply chain members’ profits, but does not always raise social welfare. When the government exclusively offers subsidies to producers, subsidies should be allocated to suppliers when there is a significant disparity in supply chain green innovation costs. Conversely, it is more beneficial to subsidize manufacturers. Consumer subsidies have the potential to enhance both environmental and economic performance in the supply chain compared with producer-exclusive subsidies, but may not always maximize social welfare when supply chain members have low unit costs associated with green innovation.

This study examines the optimal decisions for green supply chain innovation and government subsidy strategies. Supply chain members and the government can use the information system to collect and evaluate the cost of upstream and downstream green innovation, and then develop reasonable collaborative green innovation and subsidy strategies.

The replenishment of construction materials heavily relies on the functioning of heavy machinery, which often leads to confusion and negotiations among construction work groups regarding the allocation rights of these materials. When multiple groups require the same construction materials, they often struggle to determine whether the delivered materials are intended for their own use or if they have encroached upon supplies designated for others. Such uncertainties and negotiations frequently result in delays in construction progress and have the potential to escalate into conflicts. To minimize misunderstandings among work groups and mitigate the risk of severe safety consequences, it is crucial to understand the decision-making processes involved in the interaction between work groups.

This paper adopts a game theory approach to examine the interactions among work groups from a safety perspective. Quantum response equilibrium (QRE), as a specialized form of game with incomplete information, is assumed to govern the behavior of work groups in this study. By conducting a questionnaire survey, interactive scenarios were simulated. A resource overlap scenario for high-altitude construction is established, with the key factors being the importance of construction materials, the time required to supplement materials, whether managers are present and the climate within the groups. The model parameters were estimated using the expectation–maximization algorithm. Additionally, individual traits and safety awareness are surveyed in the questionnaire, further explaining the results of the game.

The findings indicate that the likelihood of conflicts between work groups under resource overlap can be quantified. The radical behavior of construction work groups exhibits a positive correlation with the importance of construction materials and the time required for material replenishment. Furthermore, the presence of a safety climate and the oversight of management personnel play a significant role in maintaining the composure of construction work groups. The expanded results of the questionnaire demonstrate that there is considerable room for improvement in workers' safety awareness, and management approaches can be further enhanced to prevent unsafe behaviors from occurring.

A novel game theory model was developed to evaluate the behavior of construction groups in situations of resource overlap. This model offers practical suggestions to improve safety performance and efficiency in construction projects.

The paper aims to identify a suitable generic brake force distribution ratio (β) corresponding to optimal brake design attributes in a diminutive driving range, where road conditions do not exhibit excessive variations. This will intend for an appropriate allocation of brake force distribution (BFD) to provide dynamic stability to the vehicle during braking.

Two techniques are presented (with and without wheel slip) to satisfy both brake stability and performance while accommodating variations in load sharing and road friction coefficient. Based on parametric optimization of the design variables of hydraulic brake using evolutionary algorithm, taking into account both the laden and unladen circumstances simultaneously, this research develops an improved model for computing and simulating the BFD applied to commercial and passenger vehicles.

The optimal parameter values defining the braking system have been identified, resulting in effective β = 0.695 which enhances the brake forces at respective axles. Nominal slip of 3.42% is achieved with maximum deceleration of 5.72 m/s² maintaining directional stability during braking. The results obtained from both the methodologies are juxtaposed and assessed governing the vehicle stability in straight line motion to prevent wheel lock.

Optimization results establish the practicality, efficacy and applicability of the proposed approaches. The findings provide valuable insights for the design and optimization of hydraulic drum brake systems in modern automobiles, which can lead to safer and more efficient braking systems.