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For oil film thickness measurement using ultrasonic spring model, obtaining the isolated reflection from the oil film layer is the key point. While for oil film thickness measurement in thrust bearings with thin liner, the reflection from the substrate-Babbitt interface will overlap with the reflection from the oil film layer. This overlapping will render the ultrasonic spring model invalid. To obtain the isolated reflected signal from the oil film layer accurately, an adaptive method was developed to recover the overlapping echoes.

A genetic-algorithm-based support matching pursuit (GA-based SMP) was developed to provide the optimal echo number and initial parameters guesses automatically and efficiently. Then, the traditional expectation maximization (EM) model was used to fine tune the accurate results.

The developed method was tested using both simulated echoes and the overlapping echoes encountered in the ultrasonic oil film thickness measurement of thrust bearings. The results demonstrated that the developed method performed well on recovering overlapping echoes adaptively.

The work shows an adaptive method to recover the ultrasonic overlapping echoes. When used in ultrasonic oil film thickness measurement, it can help extend the application of traditional ultrasonic spring model to objects with four or more layers.

Organizations' technological management capabilities (TMC) have emerged as a powerful tool to enable manufacturing firms to deal with environmental issues. This empirical investigation aims to introduce and validate a novel conceptual framework that seeks to uncover the latent relationships among the selected constructs of this study. Organizational TMC could enhance green production (GP) and reinforce the green competitive advantage (GCA) among manufacturing firms. Therefore, this research investigates the role of TMC of firms such as artificial intelligence capability (AIC), big data analytics capability (BDAC) and Internet of things capability (IOTC) in reshaping green innovation (RGI), employee development (ED), GP and GCA.

The Partial Least Squares-Structural Equation Modeling was proposed to test and validate this research’s conceptual model using 463 valid responses from manufacturing under the China–Pakistan Economic Corridor (CPEC) umbrella.

Our statistical findings confirmed that TMCs such as AIC, BDAC and IOTC supported the GP and CGA. ED and RGI positively correlated to GP. The hypotheses testing results also confirmed the mediating role of ED, RGI and GP and the moderating role of green firm innovativeness capability (GFIC) in the underdeveloped context of the manufacturing industry under the CPEC.

Moreover, the statistical findings of this study extend the existing literature by validating the possible direct, indirect/mediation and indirect/moderation relationship between TMC and GCA.

The impacts of COVID-19 on construction projects have attracted much attention in the construction management research community. Nevertheless, a systematic review of these studies is still lacking. The purpose of this paper is to systematically analyze the impacts of COVID-19 on the different stages of a project life-cycle, and comprehensively sort out the epidemic response measures adopted by project participants. In addition, the study also attempts to explore the challenges and opportunities faced by project management practitioners under the context of COVID-19.

This study comprehensively demonstrates the systematic review process of COVID-19 related research in the construction industry, systematically summarizes the research status of the impact of COVID-19 on construction projects, and defines the strategies to deal with COVID-19 in project management; and through the visualization research, determines the current key research topics and future research trends.

This study identifies 11 construction activities in the project management life cycle that are affected by COVID-19 and finds that the COVID-19 epidemic has the greatest impact on construction workers, construction standards, construction contracts and construction performance. The study further summarizes the six main epidemic countermeasures and mitigation measures taken within the construction industry following the arrival of the epidemic. In addition, the results of this study identify opportunities and future trends in intelligent construction technology, rapid manufacturing engineering and project management in the construction industry in the post-epidemic era through literature results, which also provide ideas for related research.

COVID-19 has brought severe challenges to society. It is of great significance for the future sustainable development of the construction industry to identify the impact of COVID-19 on all phases of the project and to promote the development of coping strategies by project stakeholders.

First of all, there is little study comprehensively reviewing the impacts of COVID-19 on the different stages of construction projects and the strategies to deal with the negative impacts. In addition, from a life cycle perspective, the used articles in this study were grouped into different categories based on project stages. This promotes an integrated and comprehensive understanding of historical studies. Moreover, on the basis of a comprehensive review, this paper puts forward future research directions to promote the sustainable development of the construction sector.

Construction workers’ safety behavior has been proven to be crucial in preventing occupational injuries and improving workplace safety, and organizational safety support provides essential resources to promote such behavior. However, the specific mechanisms of how organizational safety support affects safety behavior have not been thoroughly explored. Therefore, this study explored the relationship between workers’ perceived organizational safety support (perceived supervisor/coworker safety support) and safety behavior (safety task/contextual behavior), while considering the mediating effects of safety motivation, emotional exhaustion, and the moderating effect of psychosocial safety climate.

Based on the quantitative research method, the hypothesis was tested. The data were collected from 500 construction workers using a structured questionnaire. Observed variables were tested using confirmatory factor analysis, and the path coefficient of fitted model was then analyzed including the associated mediating and moderating effects.

The study found that (1) safety support from both supervisors and coworkers directly forecasted both types of safety behavior, (2) safety motivation was primarily predicted by perceived supervisor safety support, and perceived coworker safety support better predicted emotional exhaustion. Safety motivation mediated the relationship between perceived supervisor safety support and safety contextual behavior, and emotional exhaustion mediated the relationship between both types of safety support and both types of safety behavior, (3) psychosocial safety climate moderated the pathway relationships mediated by safety motivation and emotional exhaustion, respectively.

The samples of this study were mostly immersed in eastern culture and the construction industry, and the cultural and industry diversity of the samples deserves further consideration to enhance the universality of the results. The cross-sectional approach may have some impact on the accuracy of the results. In addition, other potential mediating variables deserve to be explored in future studies.

This study provides a new basis for extending current theoretical frameworks of organizational safety support and safety behavior by using a moderated mediation model. Some practical insights on construction safety management have also been proposed based on the research findings. It is recommended that practitioners should further raise awareness of the critical role of supervisor-worker and worker-coworker relationships, as high levels of safety support from the supervisor/worker respectively effectively encourage safety motivation, alleviate emotional exhaustion, and thus improve workers’ safety performance. Meanwhile, the psychosocial health conditions of workers should also receive further attention.

Environmental sanctions and pressure from governments and customers can play an essential role in driving the manufacturing industry to adopt more sustainable practices and reduce their environmental impact. Thus, this study explores how pressures from customers and governments influence sustainable firm performance and customer satisfaction through green production, green creativity, green brand innovativeness and green brand image in the Chinese manufacturing industry? Further, the moderating role of green knowledge was analyzed.

640 valid responses from the Chinese manufacturing industry were collected through web-based and physical surveys and later assessed through structural equation modeling.

The findings of this study validated the direct relationship between the proposed construct. Mediation analysis found the mediating role of green brand innovativeness, green brand image green and customer satisfaction. Furthermore, the moderating impact of green knowledge was also proved.

The empirical findings of this research filled the literature gap on cleaner production and sustainable firm performance by focusing on green production, green creativity and green knowledge in the Chinese manufacturing industry context.

The Chinese construction industry is experiencing a rapid growth these days. Due to the requirements of energy conservation, emission reduction and construction waste management, the development of prefabricated buildings (PBs) has attracted much attention in the Chinese construction industry. However, the development of PBs are still in their infancy in China, which have been negatively impacted by many obstacles. It is of great significance to clarify and analyze these obstacles for the purpose of promoting the development of PBs in China. Due to the wideness and complex features of obstacles, the existing literature exploring the research topic lacks comprehensiveness. The purpose of this paper is to systematically identify and discuss the obstacles that hinder the development of PBs in China.

This paper adopts the method of news report analysis based on the news reports retrieved from China National Knowledge Infrastructure (CNKI) and nine major portals in China. The Term Frequency-Inverse Document Frequency (TF-IDF) method of content analysis was used to rank the obstacles according to their importance.

A total of 79 obstacles to the development of PBs in China are identified, and the 79 obstacles are divided into 8 dimensions. Among the Top 20 obstacles, the government dimension accounted for the highest number of 5, the market and consumer dimension and development organization dimension were 4, Manufacturing Enterprise of Prefabricated Components (PCs) dimension, construction organization dimension and design organization dimension were 2, logistics enterprise dimension was 1, and industry association dimension was 0. Among them, the biggest obstacle is the high transportation costs.

First, data collection may not be very comprehensive. Second, this paper is only based on the obstacles in the development of PBs in China, and the universality of the management conclusions needs to be further strengthened.

The research results help the stakeholders in the Chinese PBs industry to better understand the barriers hindering the industry development in a systemic way, which will help propose appropriate strategies to address these barriers.

This paper clarifies the obstacles of China's PBs and makes an analysis, which is of great value to the development of China's PBs.

The purpose of this paper is to summarize the current applications of BIM, the integration of related technologies and the tendencies and challenges systematically.

Using quantitative and qualitative bibliometric statistical methods, the current mode of interaction between BIM and other related technologies is summarized.

This paper identified 24 different BIM applications in the life cycle. From two perspectives, the implementation status of BIM applications and integrated technologies are respectively studied. The future industry development framework is drawn comprehensively. We summarized the challenges of BIM applications from the perspectives of management, technology and promotion, and confirmed that most of the challenges come from the two driving factors of promotion and management.

The technical challenges reviewed in this paper are from the collected literature we have extracted, which is only a part of the practical challenges and not comprehensive enough.

We summarized the current mode of interactive use of BIM and sorted out the challenges faced by BIM applications to provide reference for the risks and challenges faced by the future industry.

There is little literature to integrate BIM applications and to establish BIM related challenges and risk frameworks. In this paper, we provide a review of the current implementation level of BIM and the risks and challenges of stakeholders through three aspects of management, technology and promotion.

This paper aims to measure the oil film thickness between the roller and the inner ring in roller bearings by the ultrasonic method. The oil film thickness between the roller and the inner ring in roller bearings is a key performance indicator of the bearing lubrication condition. As the oil film is very thin and the contact region is very narrow, measurement of this film thickness is very challenging. A promising ultrasonic method was used to measure this film thickness, and this method was expected to overcome some drawbacks in other methods.

A simplified roller bearing only configured one roller, and an inner ring was built up to investigate this measurement. A miniature piezoelectric element is bonded on the inner surface of the inner ring to measure the reflection coefficient from the layer of oil between the roller and the inner raceway. As the width of the line contact region is smaller than the width of the piezoelectric element, a ray model is used to calibrate the reflection coefficient measured. The quasi-static spring model is then used to calculate oil film thickness from the corrected reflection coefficient data.

The results measured by this method agree reasonably well with predictions from elastohydrodynamic lubrication (EHL) theory. Also, a dynamic displacement of the rig caused by the skid of the roller versus the inner ring was found under light-load and high-speed conditions.

This work shows that the oil film between the roller and the inner raceway in roller bearings can be measured accurately by ultrasound and shows a deal method when the contact width is smaller than the piezoelectric element width.

The purpose of this paper is to provide a nondestructive monitoring method based on wireless sensor technology to measure the continuous circumferential film pressure on radial cross-section of water-lubricated bearing, in addition, to study the influence factors to wireless communication.

The unique shaft and wireless equipments are designed, the pressure sensors are installed in right shoulder of shaft, the wireless transmitter is installed at the end of shaft and the sensors are connected with wireless transmitter by data cable. By this way, the film pressure can be obtained via wireless communication. The film pressure of eight grooved water-lubricated rubber bearings with concave staves is measured, the performance evaluation of wireless equipments is conducted and the influence factors to wireless communication is analyzed by Doppler frequency shift theory.

The rupturing and nonuniform water film is observed, the grooves decrease the film pressure of rubber bearing which is in mixed lubricating state. The main influence factor to wireless communication is shaft speed which has greater effect on packet loss rate than that on bit error rate.

By studying the actual continuous water film pressure, the bearing properties can be studied in-depth, and this has significant meaning to the design and application of bearing. Moreover, the study on influence factors to wireless communication can be used for references to other wireless monitoring on rotating machinery.

The continuous water film pressure can be monitored by this method, the lubricating state of bearing working surface cannot be damaged and the signal attenuation can be avoided. Therefore, the measuring accuracy is promoted and the measuring process also becomes convenient and high efficiency.