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The purpose of this paper is to study the aerodynamic characteristics and uplift force tendencies of pantographs within the operational height span of 1,600–2,980 mm, aiming to offer valuable insights for research concerning the adaptability of pantograph-catenary systems on double-stack high container transportation lines.

Eight pantograph models were formulated based on lines with the contact wire of 6,680 mm in height. The aerodynamic calculations were carried out using the SST k-ω separated vortex model. A more improved aerodynamic uplift force method was also presented. The change rule of the aerodynamic uplift force under different working heights of the pantograph was analyzed according to the transfer coefficients of the aerodynamic forces and moments.

The results show that the absolute values of the aerodynamic forces and moments of the upper and lower frame increase with the working height, whereas those of the collector head do not change. The absolute values of the transfer coefficients of the lower frame and link arm were significantly larger than those of the upper frame. Therefore, the absolute value of the aerodynamic uplift force increased and then decreased with the working height. The maximum value occurred at a working height of 2,400 mm.

A new method for calculating the aerodynamic uplift force of pantographs is proposed. The specifical change rule of the aerodynamic uplift force of the pantograph on double-stack high container transportation lines was determined from the perspective of the transfer coefficients of the aerodynamic forces and moments.

In view of the current difficulty of separation of troxerutin, the purpose of the paper is to separate and purify semi-synthetic flavonoid compound troxerutin by macroporous adsorption resin (SZ-3).

Comparing the adsorption performance and resolution of three different polar resins and choosing a resin to optimize the process parameters such as sample volume, eluent concentration and elution temperature to obtain high-purity troxerutin. After separating and enriching by resin column chromatography, detected the sample by LC-MS analysis.

This research found that the optimal conditions of the adsorption and desorption were sample volume S = 90 mg/g resin, methanol concentration C = 25%, T = 20 °C. the content of troxerutin increased significantly from 88% to more than 96%. Then confirmed the sample was troxerutin by LC-MS. In addition, the resin could be used for at least 10 cycles in the separation and purification experiments of troxerutin.

Purification of troxerutin with new SZ-3 resin for the first time. Under the optimal conditions, the purity and recovery of troxerutin was 96.4% and 39%. In this study, the authors established a purification process of troxerutin successfully that was simple, economical, environment friendly, with high purity and high recovery rate to provide a reference program for changing the status of troxerutin separation difficulties.

The purpose of this study is to investigate the impact of customer concentration on the provision of reverse trade credit at the firm level.

Utilizing unbalanced panel data of Chinese A-share listed firms from 2007 to 2022 as the study sample, this paper employs a fixed-effects model to investigate the association between customer concentration and firms’ reverse trade credit.

This study finds that firms with higher customer concentration receive less reverse trade credit. Heterogeneity tests reveal a significant amplification of reverse trade credit in high-tech firms but a detrimental impact in large-sized, competitive and high-analyst-following firms. Further studies conclude that firms’ motivations, including bargaining power, financing and transaction guarantee motivations, collectively influence the extent of reverse trade credit acquisition.

To our knowledge, this paper represents the first attempt to conduct a comprehensive investigation of reverse trade credit, specifically through the lens of customer concentration, utilizing firm-level panel data sourced from a singular country.

Based on goal orientation theory, this study aims to examine how and when employees' performance goal orientations (PGOs) affect their change-supportive behavior in entrepreneurial firms undergoing change.

A two-wave time-lagged research design was applied to collect data from companies undergoing change in China.

The results showed that employees' performance-proving goal orientation (PPGO) was positively related to change-supportive behavior, and employees' performance-avoiding goal orientation (PAGO) was negatively related to change-supportive behavior. Openness to change played a mediating role in these mechanisms, and employees' learning goal orientation (LGO) played a moderating role.

By solving the mechanism of the relationship between PGOs and change-supportive behavior that has not been explored before, this study answers the question of how and when different PGOs affect support behavior.

With the rapid development of the pipeline transportation and exploitation of mineral resources, it is urgent requirement for the high-performance polymer matrix composites with low friction and wear to meet the needs of solid material transportation. This paper aims to prepare high-performance ultrahigh molecular weight polyethylene (UHMWPE) matrix composites and investigate the effect of service condition on frictional behavior for composite.

In this study, UHMWPE matrix composites with different content of MoS₂ were prepared and the tribological performance of the GCr15/composites friction pair in various sliding speeds (0.025–0.125 m/s) under dry friction conditions were studied by ball-on-disk tribology experiments.

Results show that the frictional behavior was shown to be sensitive to MoS2 concentration and sliding velocity. As the MoS2 content is 2 Wt.%, composites presented the best overall tribological performance. Besides, the friction coefficient fluctuates around 0.21 from 0.025 to 0.125 m/s sliding speed, while the wear rate increases gradually. Scanning electron microscopy images, energy-dispersive spectroscopy and Raman Spectrum analysis present that the main wear mechanisms were abrasive and fatigue wear.

The knowledge obtained herein will facilitate the design of UHMWPE matrix composites with promising self-lubrication performances which used in slag transport engineering field.

The wavelet neural network (WNN) has the drawbacks of slow convergence speed and easy falling into local optima in data prediction. Although the artificial bee colony (ABC) algorithm has strong global optimization ability and fast convergence speed, it also has the drawbacks of slow speed while finding the optimal solution and weak optimization ability in the later stage.

This article uses an ABC algorithm to optimize the WNN and establishes an ABC-WNN analysis model. Based on the example of the Jinan Yuhan underground tunnel project, the deformation of the surrounding rock of the double-arch tunnel crossing the fault fracture zone is predicted and analyzed, and the analysis results are compared with the actual detection amount.

The comparison results show that the predicted values of the ABC-WNN model have a high degree of fitting with the actual engineering data, with a maximum relative error of only 4.73%. On this basis, the results show that the statistical features of ABC-WNN are the lowest, with the errors at 0.566 and 0.573, compared with the single back propagation (BP) neural network model and WNN model. Therefore, it can be derived that the ABC-WNN model has higher prediction accuracy, better computational stability and faster convergence speed for deformation.

This article uses firstly the ABC-WNN for the deformation analysis of double-arch tunnels. This attempt laid the foundation for artificial intelligence prediction in deformation analysis of multi-arch tunnels and small clearance tunnels. It can provide a new and effective way for deformation prediction in similar projects.

This study examines the interdependent relationships between green supply chain management (GSCM), carbon neutrality capability (CNC), digital transformation (DT) and firm performance (FP) among enterprises listed on the Chinese stock market. The primary objective is to provide a scholarly examination that may help these organisations to enhance their GSCM practices significantly.

Drawing on data from mainland Chinese publicly listed firms over the period from 2014 to 2021, this study posits and methodically evaluates four hypotheses: (1) GSCM practices are positively associated with an increase in CNC; (2) GSCM practices have a beneficial impact on FP; (3) DT moderates the GSCM–FP relationship and (4) CNC mediates the effect of GSCM on FP.

Contrary to initial assumptions, the findings suggest that GSCM practices may initially have a negative impact on FP. However, a concerted focus on CNC has the potential to convert this negative trajectory into a positive influence on FP. The findings further identify that DT has a significant moderating effect on the GSCM–FP relationship.

The findings of this study enrich the academic discourse concerning the symbiotic effects of GSCM, CNC and DT on FP. By systematically analysing these dynamics, the study underscores the critical importance of CNC and DT in the successful application of GSCM practices, thus offering valuable contributions to the literature on sustainable corporate operations.

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 purpose of this study is to develop an optimization method for charging plans with the implementation of time-of-day (TOD) electricity tariff, to reduce electricity bill.

Two optimization models for charging plans respectively with fixed and stochastic trip travel times are developed, to minimize the electricity costs of daily operation of an electric bus. The charging time is taken as the optimization variable. The TOD electricity tariff is considered, and the energy consumption model is developed based on real operation data. An optimal charging plan provides charging times at bus idle times in operation hours during the whole day (charging time is 0 if the bus is not get charged at idle time) which ensure the regular operation of every trip served by this bus.

The electricity costs of the bus route can be reduced by applying the optimal charging plans.

This paper produces a viable option for transit agencies to reduce their operation costs.

Specific types of Hispanic-owned banks (HOBs), including those related to Brazilian, Cuban, Mexican or Puerto Rican heritage, have not be analyzed to date. There are important differences between the relevant communities, including geographic location, language barriers, population size and the importance of remittances to foreign nations. The analysis here sheds light on these differences.

HOBs with the Federal Deposit Insurance Corporation (FDIC)-designated minority-owned depository institution (MDI) designation are identified, along with bank ownership heritage. Financial data, a measure of market competition, and demographics of depositors from 2003 to 2017 are utilized in an exploratory analysis comparing banks by HOB type, with random effects regressions for the pre-collapse (2003–2006) and post-collapse (2009–2017) periods.

Although each of the four types of HOBs serve Hispanic and poor communities, there are substantial differences. For example, Brazilian and Puerto Rican banks on the island held high levels of nonperforming loans (NPLs) post-collapse, with the Brazilian and Mexican banks expanding levels of risky commercial real estate (CRE) lending post-collapse, while the Cuban banks contracted CRE lending. Differences in terms of return on assets (ROAs), the cost of borrowed funds and the tier-1 risk-based capital ratio are also identified.

HOBs, like Latinos in the USA, are culturally heterogeneous and likely operate in different ways depending upon the culture and economic circumstances of the communities where they operate.

Although there is substantial research on MDIs, this is the first analysis which treats HOBs as culturally heterogeneous. Further research of this type is warranted.