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This paper aims to optimize the air pressure regulation scheme of the aeroengine pressure test bench.

Based on the requirements of pressure regulation process and the operating mechanism of aeroengine pressure test bench, a grey performance evaluation index system is constructed. The combination of principal component analysis and grey theory is employed to assign weights to grey indexes. The grey target evaluation model is introduced to evaluate the performance of historical regulation processes, and the evaluation results are analyzed to derive optimization mechanism for pressure regulating schemes.

A case study based on monitoring data from nearly 300 regulation processes verifies the feasibility of the proposed method. On the one hand, the improved principal component analysis method can achieve rational weighting for grey indexes. On the other hand, the method comparison intuitively shows that the proposed method performs better.

The pressure test bench is a fundamental technical equipment in the aviation industry, serving the development and testing of aircraft engines. Due to the complex system composition, the pressure and flow adjustment of the test bench heavily rely on manual experience, leading to issues such as slow adjustment speed and insufficient accuracy. This paper proposes a performance evaluation method for the regulation process of pressure test bench, which can draw knowledge from historical regulation processes, provide guidance for the pressure regulation of test benches, and ultimately achieve the goal of reducing equipment operating costs.

Surface defects are often present on the surface of continuous casting slabs and rolled products. A lot of surface defects of hot rolled products are inherited from initial defects on continuous casting slabs. This work aims to trace the original surface defect during the whole heavy rail rolling and avoid black line surface defect that appears on the surface of heavy rail finial product.

Artificial round hole-shaped surface defects on the surface of continuous casting slab during the hot rolling of 60 kg/m heavy rail are analyzed experimentally and by means of explicit dynamic finite element method (FEM) and modified model rebuilding method.

The calculated results of surface defect locations of heavy rail finial product are in good agreement with the experimental ones. It is shown that the explicit dynamic FEM and modified model rebuilding method can be used effectively to predict the flow behavior of surface defects in the hot rolling of 60 kg/m heavy rail.

The three-dimensional finite element model for whole heavy rail rolling is built using explicit dynamic code and modified model rebuilding method. Flow behavior of black lines is studied in the 60-kg/m heavy rail rolling. The simulation results of six typical points are in good agreement with the experimental results.

This paper aims to provide a new drilling entry board for printed circuit board (PCB) process, superior in heat dissipation, lubrication, water solubility and hole location accuracy, achieving an excellent drilling process.

Using a mixture of polyethylene glycol (PEG) and water-soluble adhesives as hydrosoluble, endothermic and lubricant resins and aluminum foils as baseplates, a series of coated and aluminous entry boards (CABs) for PCB drilling was successfully prepared. The surface appearance of the entry boards was observed clearly by scanning electron microscopy (SEM). The endothermic and lubricant effects of the resins applied on the CABs was characterized by differential scanning calorimetry (DSC) and their water solubility was tested in the normal-temperature water (25°C). Moreover, the CABs’ good drilling properties were tested when they were used for PCB drilling.

The SEM analysis showed that the surfaces of the resin layers coated on the CABs whose coating thicknesses were less than 80 μm were smoother and flatter, which could improve hole location accuracy and reduce drill breakage ratio. By virtue of DSC, the endothermic and lubricant effects of the CABs were proven. The fusion of PEG in the resin layers could absorb the heat produced by drilling, restrain the temperature of the drill bit and hole rising and lubricate the drill bit efficiently when a hole was being drilled, which could achieve high-quality holes with good production efficiency. The water-soluble test showed that the prepared CABs had excellent water solubility at normal temperature, enabling the resin left on the hole walls and in the flute of the drill bit to be washed away easily and thereby improving the drilling efficiency and quality. The drilling tests showed that the increase in the thickness of the CABs’ coating could improve the hole location accuracy and alleviate the bit wear. In addition, the suitable coating thickness could ensure the firm adhering of the resin coating the aluminum foil, effectively avoid drill intertwist and prevent the resin debris from blocking the drilled holes on the surface of the entry board, which could hinder chip removal, resulting in poor hole wall quality and drill breakage.

This paper has a remarkably high industrial practicality in the PCB manufacture process.

Criticality cognitions regarding the same workplace event often differ between leaders and employees. Nevertheless, its consequences on employee work outcomes remain unknown. In this study, we draw on cognitive dissonance theory to examine how and why leader–employee differences in cognitions of workplace event criticality impact employee job-related outcomes.

Wu used multilevel polynomial regression analyses from a time-lagged, multi-source field study with 145 leader–employee dyads to test our proposed model.

Leader–employee differences in cognitions of workplace event criticality can bring both benefits and perils to employees. Specifically, such differences can cause employee rumination, which in turn leads to an increase in both employee voice and fatigue.

This study contributes to the event and cognitive discrepancy literature in four ways. First, prior event studies largely adopted a singular employee perspective for investigation (e.g. Chen et al., 2021; Lin et al., 2021). By examining the impacts of event criticality from the dual perspective of leaders and employees, we attain a more comprehensive understanding of the implications of workplace events in organizational life. Second, extant studies have predominantly focused on the dark side of cognitive discrepancy (e.g. Bashshur et al., 2011; Erdogan et al., 2004; Grandey et al., 2013). Our study reveals that leader–employee differences in criticality cognitions can have both a bright and a dark side on employee outcomes, offering a more balanced and dialectical view of the consequences of cognitive discrepancy. Third, drawing on cognitive dissonance theory, we introduce employee rumination as an underlying mechanism to explain the impacts of leader–employee differences in criticality cognitions on employee voice and fatigue. Finally, while prior cognitive dissonance research has primarily employed an intrapersonal perspective (e.g. Sivanathan et al., 2008; Pugh et al., 2011; Grandey et al., 2013), our study adopts an interpersonal lens and underscores that interpersonal differences in cognitions can also serve as an example of cognitive discrepancy to instigate internal dissonance processes. By doing so, we enrich our understanding of cognitive dissonance theory.

The purpose of this paper is to explore the variation law between the clay microstructure and macro external force by using soil scanning electron microscope (SEM) images.

First, SEM images of clay were pre-processed by MATLAB, and quantitative statistical parameters such as directional probability entropy, fractal dimension and shape factor are extracted. Second, the distribution force model was proposed, considering that the microscopic parameters of soil particles were independent of each other, and the distribution coefficient was determined according to the analytic hierarchy process (AHP). Then, the fitted formula of quantitative statistical parameters based on the distribution force model was obtained by taking the macroscopic distribution force as independent variable and the microscopic parameters of soil particles as dependent variable. Finally, the correctness of corresponding fitting formula was verified.

The results showed that the change of external consolidation pressure has great influence on the directional probability entropy and fractal dimension, while the shape factor reflecting the regular degree of soil particle shape is less sensitive to the consolidation pressure. The fitting formula has high accuracy, and mostly the R value can reach more than 0.9. All the data have passed the test, which proves that the distribution force model proposed in this paper is rational.

The model can be used to connect the macroscopic stress of soil with the micro-structure deformation of soil particles through mathematical formula, which can provide reference for engineering practice.

In this study, suggestions on the protection and development of marine resources, sea area use and management, improvement of laws and regulations, monitoring of marine resources and impact assessment of marine environment are put forward.

Literature research method.

A major factor contributing to the decline in fishery resources is excessive fishing. At present, there are many problems to be solved in the exploitation and utilization of marine mineral resources in China. The pollution problem of marine tourism resources is becoming increasingly serious. Overmining of coastal sea resources has led to planning and management failures.

This paper discusses the current situation of marine resource exploitation and protection in China and analyzes the reasons for excessive resource exploitation from three aspects of marine concept, laws and regulations and marine management.

The purpose of this paper is, from a resource accumulation and resource allocation perspective, to examine the variant effects of government subsidies among firms with varying levels of market power and to test how industry competition moderates the relationship between market power and allocative efficiency of government subsidies.

This study explores the relationship between government subsidies and firm performance from a resource-based view. The authors study the moderating role of market power and three-way interaction between subsidy, market power and industry competition on firm performance. The authors test their hypotheses using a sample of Chinese A-share manufacturing firms from 2006–2019. The authors apply firm-level panel data regressions and conduct a series of robustness tests. The marginal effect of market power and industry competition is explored via three-way moderator effect models.

This study finds that government subsidies are negatively related to firm performance. Market power, on average, strengthens the negative effect of government subsidies on performance, but such a reinforcement effect is neutralized when industry competition is intense. Government subsidies are least efficiently used when firms have market power and industry competition is low. In addition, the authors use different forms of firm performance and a various of robustness tests to verify their assumptions.

This paper contributes to the literature as follows. First, the authors look into subsidy–performance problem from the perspective of the resource-based view and contribute to explaining and mitigating the divergence of current findings on the subsidy–performance relationship. Second, the authors introduce market power and industry competition as moderators to study how resource allocative efficiency affects the subsidy–performance relationship. Third, the authors propose that managerial incentives have played an important role in the allocation of government subsidies, which enriches management practices.

With the help of multi-body dynamics software UM, the paper uses Kik–Piotrowski model to simulate wheel-rail contact and Archard wear model for rail wear.

The CRH5 vehicle-track coupling dynamics model is constructed for the wear study of rails of small radius curves, namely 200 and 350 m in Guangzhou East EMU Depot and those 250 and 300 m radius in Taiyuan South EMU Depot.

Results show that the rail wear at the straight-circle point, the curve center point and the circle-straight point follows the order of center point > the circle-straight point > the straight-circle point. The wear on rail of small radius curves intensifies with the rise of running speed, and the wearing trend tends to fasten as the curve radius declines. The maximum rail wear of the inner rail can reach 2.29 mm, while that of the outer rail, 10.11 mm.

With the increase of the train passing number, the wear range tends to expand. The rail wear decreases with the increase of the curve radius. The dynamic response of vehicle increases with the increase of rail wear, among which the derailment coefficient is affected the most. When the number of passing vehicles reaches 1 million, the derailment coefficient exceeds the limit value, which poses a risk of derailment.

An increasing number of customers are using customer-to-customer (C2C) platforms to buy and sell products and services. Despite this growth, little research has examined customer experiences with C2C e-commerce. This study examines how informational and emotional interactions affect customer patronage behaviors by increasing customer trust in both sellers and platforms.

A self-administered questionnaire was used to collect data from 181 customers of C2C platforms in the United States. Partial least squares structural equation modeling was used to analyze the data.

The results show that informational interactions affect customer trust both in sellers and platforms, resulting in customer loyalty. The findings also show that emotional interactions affect customer trust in sellers. Multi-group analyses suggest that the impacts of informational and emotional interactions on trust vary depending on customer demographics.

Theoretical implications in this study arise from (1) examination of customer experiences with C2C platforms using the stimulus-organism-response framework, (2) identification of the role of informational and emotional interactions in the formation of trust and (3) exploration of the ways in which customer gender, age and income affect the connection between experiences and consequences in C2C settings.

From a practical perspective, this study provides useful guidelines to help C2C business practitioners increase customer patronage behavior by means of interactions and trust.

This study provides practical and academic implications by examining how customer interactions affect customer trust in e-commerce C2C platforms.

Tremendous growth and worldwide expansion of Islamic banking industry has gained widespread attention of economist, bankers, investors and financial experts regardless of economic and political volatility in global banking industry. To compete with conventional banking, Islamic banks are setting up themselves with innovative technologies to gain competitive edge and market share. The establishment of mobile banking has been proven a technological wonder by eliminating time and space boundaries, and one can access financial services anywhere and at any time. For effective market segmentation, recognizing gender differences in factors affecting the adoption patterns of m-banking may provide competitive edge. Therefore, this paper aims to investigate how gender differences impact the intention to adopt Islamic mobile banking in Pakistan.

The study uses extended technology acceptance model (TAM) on final 243 participants from Pakistan. Confirmatory factor analysis (CFA) and structural equation modeling (SEM) methodology has been applied for data analysis using SPSS 21 and AMOS 21.

Results have identified two interesting and different models for males and females in intention to adopt Islamic mobile banking. It is inferred that males are more task driven and desire for personality, value and status, so their intention is significantly impacted by perceived usefulness and perceived self-expressiveness. Whereas, females have found lack of IT knowledge and trust; therefore, their intention is significantly impacted by perceived credibility. However, the perceived financial cost was found of no concern for both males and females and social norms influenced the adoption, but there existed no significant gender differences.

The contribution of this study to existing literature is twofold. First, the existing research on mobile banking has mainly applied TAM on conventional banking overlooking the important ethnic group, the Muslims, who prefer Islamic banking. Second, the impact of gender differences is investigated in factors affecting intention to adopt Islamic mobile banking that has not been studied previously. The study fills the gap.