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The purpose of this study is to investigate the tribological performance of helical gear pairs with consideration of the properties of non-Newtonian lubricant and the real three-dimensional (3D) topography of tooth flanks.

Based on the mixed elastohydrodynamic lubrication (EHL) theory for infinite line contact, this paper proposes a complete model for involute helical gear pairs considering the real 3D topography of tooth flanks and the properties of non-Newtonian lubricant. Film thickness, contact load and contact area ratios at the mid-point of contact line are studied for each angular displacement of pinion. Both the total friction coefficient and surface flash temperature are calculated after obtaining the values of pressure and subsurface stress. Then, the influences of input parameters including rotational speed and power are investigated.

During the meshing process, contact load ratio and area ratio of the two rough surface cases first increase and then decrease; the maximum flash temperature rise (MFTR) on the gear is lower than that on the pinion first, but later the situation converses. For cylindrical gears, on the plane of action, there is a point or a line where the instantaneous friction reduces to a minimum value in a sudden, as the sliding–rolling ratio becomes zero. When rotational speed increases, film thickness becomes larger, and meanwhile, contact load ratio, coefficient of friction and MFTR gradually reduce.

A comprehensive analysis is conducted and a computer program is developed for meshing geometry, kinematics, tooth contact, mixed EHL characteristics, friction, FTR and subsurface stress of involute helical gear pairs. Besides, a numerical simulation model is developed, which can be used to analyze mixed lubrication with 3D machined roughness under a wide range of operating conditions.

The development and evolution of stakeholder collaborative innovation in megaprojects is impacted by various influencing factors. The effect of influencing factors on collaborative innovation performance (CIP) in megaprojects is not a simplistic linear relationship but an iterative and non-linear relationship that requires a dynamic perspective to analyze. Therefore, this paper adopts the system dynamic (SD) approach to investigate the dynamic and interactive relationships between the CIP and the influencing factors.

The study first develops a research framework with the system boundary of “CIP system – organizational collaboration subsystem – knowledge collaboration subsystem – strategic collaboration subsystem”. Then, the causal relationship model, the stock-flow model, and the mathematical equations were determined based on the literature review and the expert interviews. Finally, five performance improvement scenarios were designed according to the practice context of CIP in megaprojects, and simulations were performed using the Vensim PLE software to investigate the CIP from a dynamic perspective.

The findings reveal that the effect of different influencing factors on CIP grows non-linearly, with the cumulative effect becoming more pronounced as time advances. The incentive mechanism has the most significant effect, and the combined effect of multiple influencing factors has a highly significant facilitating effect on improving CIP. Strategic collaboration, organizational collaboration and knowledge collaboration are mutually conditional and reinforcing with each other, which ultimately promotes the improvement of CIP.

This study uncovers the inherent pattern and the interactive dynamic mechanism of factors for improving CIP in the context of megaprojects. It enriches the theoretical research in the area of collaborative innovation in megaprojects and provides practical management strategies for improving CIP.

Under extensive pressure from normal market competition, frequent technological change and extreme exogenous shock, firms are facing severe challenge nowadays. How to withstand discontinuous crises and respond to normal risks through improving resilience (RE) is an important question worth researching. Thus, drawing on the strategic entrepreneurship theory, the purpose of this study is exploring the relationship between entrepreneurial orientation (EO) and RE, and combining digitization to discuss the role of digital business capability (DBC), digital business model innovation (DBMI) and environmental hostility (EH).

Based on survey data from 203 Chinese firms, using the methods of linear regression and bootstrap to test our hypothesis. Furthermore, fuzzy-set qualitative comparative analysis (FsQCA) is used to identify previously unknown combinations which lead to strong/weak RE in digital context.

First, EO positively influenced DBC and RE. Second, DBMI promoted RE, DBC and DBMI served as sequential mediators that linked EO and RE. Third, EH positively moderated the effects of EO on RE. Further the study revealed that different configuration of DBMI and dimensions of EO and DBC can explain RE.

The study explains mechanism of RE from perspective of digitization. The conclusion is good for further consolidating strategic entrepreneurship theory, and providing a new frame for firms to build the ability of antifragile.

Innovation ambidexterity is crucial for fostering growth and gaining a competitive advantage in small and medium enterprises (SMEs). Previous research indicates that achieving a balance between exploration and exploitation is a multifaceted phenomenon occurring across various levels. This paper aims to examine the influence of individual, organizational and institutional factors on the ambidextrous innovation of Chinese niche leaders using a configurational perspective.

This study uses secondary data collected from 69 Chinese niche leaders in the new equipment manufacturing industry. The authors use fuzzy-set qualitative comparative analysis to investigate how owner openness, age, digitization, the formal institutional environment and the informal institutional environment jointly influence innovation ambidexterity.

By using fuzzy set analysis, this study categorizes combinations of interdependent factors that promote innovation ambidexterity. In particular, the authors pinpoint three configurations that foster high innovation ambidexterity and two configurations that lack such high levels of innovation ambidexterity. The analysis results suggest that innovation paradoxes in SMEs are linked to a nested system comprising leadership, organizational factors and the institutional environment.

This study elucidates the mechanism of innovation ambidexterity through a configurational perspective. This research proposes and validates a framework that enables SMEs to develop ambidextrous innovation capabilities, thereby integrating organizational ambidexterity theory and shedding light on the intricately complex nature of innovation ambidexterity.

Despite the extensive research on post-disaster reconstruction projects (PDRP), there is a paucity of studies that examine critical challenges for the project practices in post-war-developing countries, particularly, Africa. The purpose of this research is to investigate the key project management challenges impacting the post-disaster reconstruction projects (PDRP) during the construction and planning stages in Angola, with an aim to fill the knowledge gap.

The primary data was collected from 130 project management practitioners working with planning, provincial government organisations including consultants, and contractors within the Angolan public sectors organisations. Response data was subjected to descriptive statistics, mean scores, and inferential statistics (One sample t-tests) and Kendall's concordance.

The descriptive and empirical analysis demonstrated a disparity of the ranking of the 21challenges affecting the PDRP among the groups; with statistically significant differences amongst the 10 challenges. Based on the overall sample, 6 out of 10 critical challenges are between (24–25) levels of agreement close to the mean. The results of the mean score ranking indicate that “working with poor or restricted access to location”, “project culture that fits the needs of local people”; “improving the capacity of local government”, “minimizing the negative effects of local people” and “relocation issues by establishing property rights during the reconstruction project” were the five critical challenges to managing PDRP whereas “improving information and communication processes”, “securing adequate resources (material and machinery)”, “dealing with rising costs of materials and labour” were considered to be the least critical.

The study was restricted to one province and Country (out of 18) namely, Luanda, Angola. Therefore, the findings may not be generalized to public sector organisations operating in different countries with different contexts, political settings and disaster complexities.

The establishment of challenges in PDRPs helps the key stakeholders by providing the foundation to project teams to address the challenges during planning and construction stages, and thus improving project delivery in the future. Understanding the uniqueness of PDRPs and interdependency of project management from the implementing organization is of particular value for the managers of future projects and other decision-makers, especially in the emerging countries. Moreover, the findings could be used to reflect on the need to formulate policies appropriate to post disaster environments, which among other issues could address building policies, which could include land ownership regulations and procedures together with property rights.

This study contributes to the body of knowledge on the subject within a previously unexplored post-war context with a focus on public organizations perspective. The study provides insights on the challenges affecting the post-disaster reconstruction across the Angolan public sector.

Rotating machineries are widely used in manufacturing, petroleum, chemical, aircraft, and other industries. To accurately identify the operating conditions of such rotating machineries, this paper aims to propose a fault diagnosis method based on sensitive dimensionless parameters and particle swarm optimization (PSO)–support vector machine (SVM) for reducing the unexpected downtime and economic losses.

A relatively new hybrid intelligent fault classification approach is proposed by integrating multiple dimensionless parameters, the Fisher criterion and PSO–SVM. In terms of data pre-processing, a method based on wavelet packet decomposition (WPD), empirical mode decomposition (EMD) and dimensionless parameters is proposed for the extraction of the vibration signal features. The Fisher criterion is applied to reduce the redundant dimensionless parameters and search for the sensitive dimensionless parameters. Then, PSO is adapted to optimize the penalty parameter and kernel parameter for SVM. Finally, the sensitive dimensionless parameters are classified with the optimized model.

As two different time–frequency analysis methods, a method based on a combination of WPD and EMD used to extract multiple dimensionless parameters is presented. More vital diagnosis information can be obtained from the vibration signals than by only using a single time–frequency analysis method. Besides, a fault classification approach combining the sensitive dimensionless parameters and PSO-SVM classifier is proposed. The comparative experiment results show that the proposed method has a high classification accuracy and efficiency.

To the best of the authors’ knowledge, very few efforts have been performed for fault classification using multiple dimensionless parameters. In this paper, eighty dimensionless parameters have been studied intensively, which provides a new strategy in fault diagnosis field.

Although leveraging social media to access healthcare information is nothing new, a boom in short video apps offers new potential for disseminating health-related information. However, it is still unclear how short video apps might facilitate and benefit users’ consumption of health information. Furthermore, the technology features of short video apps complicate attempts to conduct research about them; as a consequence, they have been understudied. For addressing these concerns, this study adopts an affordance perspective to investigate the relationship between affordances and user experience and to examine factors that contribute to users’ intention to continue using short video apps to obtain health information.

Drawing upon affordance theory, we constructed a research model that integrates four types of affordances (livestreaming, searching, meta-voicing and recommending), three types of user experience (immersion, social presence and credibility perception), and user’s intention to continue use. We employed an online survey and obtained a sample of 372 valid responses from TikTok (DouYin) users in China. The partial least squares (PLS) method was used to analyze the data.

The study found that the user experience, in terms of social presence, immersion and credibility perception, can significantly predict users’ intention to continue using short video apps to obtain health information. Furthermore, the user experience was positively associated with the different affordances provided by the short video apps.

The findings of this study have several implications. First, the study contributes to the health information behavior literature by incorporating the aspect of user experience. Moreover, the study extends the application of affordance theory to users’ health information acquisition, and it carries some practical implications on how to leverage the great potential of short video apps to serve public health communication better.

Green innovation (GI) in megaprojects has become a significant research topic that attracts both megaproject management scholars' and practitioners' attention. Green transformational leadership (GTL) is acknowledged as an important antecedent to GI in the permanent context. However, limited research investigates the mechanism and condition of how GTL effectively affects GI in the temporary (i.e. megaproject) context. This study seeks to examine the mechanism and condition of GTL in improving GI by assessing the mediating role of green knowledge sharing (GKS) and the moderating effect of innovation climate (IC).

Regression analysis was performed on data obtained from 303 experts who have been involved in megaprojects.

GTL has a significant positive impact on two aspects of GI, including green product innovation (GPDI) and green process innovation (GPCI). Besides, GKS mediates the relationship between GTL and the two aspects of GI. Moreover, IC plays a significantly positive moderating role in the relationship between GTL and GKS and the relationship between GKS and the two aspects of GI.

This study adds knowledge to the theory and practice by unveiling the “black box” between GTL and GI in the temporary (i.e. megaproject) context. First, this study extends the continuing discussion on the direct effect of GTL on GI to the temporary (i.e. megaproject) context. Second, this study facilitates the understanding of the mechanism to generate better GI performance considering the mediating role of GKS and the moderating effect of IC in the temporary (i.e. megaproject) context. The results can illuminate megaproject practitioners on generating better GI performance.

The purpose of this paper is to investigate how China's rural public pension affects farmers' formal borrowing, which has always been rationed.

This paper uses a difference-in-difference (DID) estimation to evaluate the effect of the implementation of the New Rural Pension Scheme (NRPS) at the end of 2009 on farmers' formal borrowing.

The results show that the NRPS significantly reduces farmers' formal borrowing from rural credit cooperatives (RCCs). The effect is significant among the elderly, eastern China and high-income groups.

This study contributes to the literature by identifying another potential reason for rural formal credit shortage. Policymakers and rural formal financial institutions should consider the demand side problem of lending.

Environmental crises and resource shortage have been matters of concern worldwide particularly, as the beginning of the twenty-first century. Remanufacturing can be one of the best approaches to promoting the development of circular economy and realizing the efficient use of resources. However, research studies indicate that the general public still remains unaware of the merits of remanufactured products. Hence, investigating main motivations of consumers to purchase remanufactured products is certainly worth exploring. The purpose of this paper is to find out consumers’ key motivations to purchase remanufactured products. A new multi-attributes decision-making method based on prospect theory (PT) is conducted.

Firstly, according to the prior literature, 12 main factors that influence consumers to purchase a remanufactured product are selected. Then, the single valued triangular neutrosophic numbers and triangular neutrosophic weighted geometric averaging operator are applied to rank them. Secondly, a multi-attribute decision-making method with PT is used to evaluate the utilities of new and remanufactured products, respectively. Based on the utilities, consumers’ preferred choice between the new and remanufactured products can be elicited.

The proposed method has been applied to a real survey. The results demonstrate that the proposed method is not only capable of recognizing the consumers’ key motivations for purchasing a remanufactured product but also able to deal with the ranking of the new and remanufactured products.

The contributions of this paper are threefold. Firstly, this paper attempts to explore the main motivations that encourage consumers to purchase a remanufactured product, instead of a new one. Secondly, the proposed method is established based on PT, taking consumers’ psychological behavior into consideration, which can obtain a relatively reasonable result. Thirdly, it can enrich the remanufacturing literature, serving as a guideline for consumers when purchasing a remanufactured product. In addition, this paper can help the remanufacturers make pricing and production decisions where necessary.