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While existing literature emphasizes the importance of empowerment in construction projects, the working mechanisms of empowering leadership in the project context are unclear. Based on conservation of resources (COR) theory, this study aimed to examine the relationship between empowering leadership and project performance, highlighting the mediation roles of creative self-efficacy and leadermember exchange and the moderation role of perceived overqualification.

The authors collected data from 287 project members in different projects and tested the integrated conceptual model through moderated mediation analysis with bootstrapping strategy.

The results revealed that empowering leadership was positively related to project performance through creative self-efficacy and leader–member exchange. Perceived overqualification served as significant moderator.

The findings contribute to the understanding of empowering leadership in projects by verifying and extending the resource acquisition and investment process in the project context. The results of this study also demonstrated that creative belief and social exchange facilitate the effectiveness of project members' task efforts and outcomes and that perceived overqualification might not exert a detrimental effect on project performance.

The development of project managers and leadership has been highlighted as crucial for improving project success and performance, resulting in a rise of interest in project leadership research over the last two decades. While several qualitative reviews have been conducted, there have been limited quantitative and systematic reviews on project leadership. This study fills this gap by portraying the knowledge landscape and tracking the evolution of project leadership research from 1998 to 2022 through bibliometric approaches.

Based on 816 records, including 793 articles extracted and selected from the Web of Science database and specific journals, and 23 articles selected from three non-SCI/SSCI indexed journals, the authors used CiteSpace and bibliometrix R-package to depict visualizations of the trajectory of co-cited references, the landscape of co-occurred keywords and emerging trends in project leadership via reference co-citation analysis, keyword co-occurrence analysis and thematic mapping.

The bibliometric analyses enabled the authors to understand the conceptual aspects of project leadership and its theoretical background. Three stages of the intellectual bases were identified and tracked: the infancy phase (1998–2007), the growth phase (2008–2014) and the new development phase (2015–2022). The results of keyword co-occurrence analysis indicated that the research focus evolved from investigating traits and competences to examining the effects of traditional leadership behaviors, and then considering context-specific leadership. The findings of thematic mapping and theoretical interpretation illustrate the potential directions of the competence comparison, new and appropriate leadership, and the interaction between leadership and context.

This study advanced the field by providing a systematic review of project leadership, developing potential future directions for project leadership research and providing practical implications for career development and training.

Project complexity is a critical issue that has increasingly attracted attention in both academic and practical circles. However, there are still many gaps in the research on project complexity, such as the differentiated conceptualization of complexity and disjointed operationalization in the measurements. Therefore, this paper aims to conduct a systematic and detailed literature review on the concept, dimensions, assessment, and underlying mechanisms of project complexity.

A systematic literature review methodology was applied to search and synthesize the research on project complexity, and a final sample of 74 journal articles was identified.

This study first summarizes the concepts of project complexity from three different theoretical perspectives, and then identifies different approaches of measurement, evaluation, or simulation to assess project complexity. This paper finally establishes an integrative framework to synthesize the antecedents, mediators and moderators, and outcomes of project complexity, generating four suggestions for future research.

This study summarizes the definition and operationalization of project complexity to reduce the discrepancies in the existing research and offers an integrative framework to offer a broad overview of the current understanding of project complexity, providing a potential way forward for addressing project complexity.

The welding areas of the workpiece must be consistent with high precision to ensure the welding success during the welding of automobile parts. The purpose of this paper is to design an automatic high-precision locating and grasping system for robotic arm guided by 2D monocular vision to meet the requirements of automatic operation and high-precision welding.

A nonlinear multi-parallel surface calibration method based on adaptive k-segment master curve algorithm is proposed, which improves the efficiency of the traditional single camera calibration algorithm and accuracy of calibration. At the same time, the multi-dimension feature of target based on k-mean clustering constraint is proposed to improve the robustness and precision of registration.

A method of automatic locating and grasping based on 2D monocular vision is provided for robot arm, which includes camera calibration method and target locating method.

The system has been integrated into the welding robot of an automobile company in China.

A method of automatic locating and grasping based on 2D monocular vision is proposed, which makes the robot arm have automatic grasping function, and improves the efficiency and precision of automatic grasp of robot arm.

The purpose of the study reported in this paper was to prepare modified C.I. Pigment Red (PR) 170 to reduce production cost and improve application performance. The structure of the modified pigment was characterised. The colour strength, thermal stability, mobility, aqueous dispersability and ultraviolet (UV) resistance of modified pigments were studied.

Silica fume was added into the diazonium salt solution under acidic condition, followed by the activation to generate new surface. Subsequently, coupling component was dropwise added to the system to form the modified pigments evenly on the surface of silica fume in situ. The structure and properties of the modified pigment were studied by fourier transform infrared spectoscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravity analysis (TG-DTA), UV-visible diffuse reflectance spectra (UV-Vis DRS), and commission internationale de L‘Eclairage (CIE L*a*b*) colour measurements.

The morphology and particle size of the modified pigment were controlled by the modification of the silica fume, and the organic pigment and silica fume formed a core–shell structure. The properties of the modified pigment including colour strength, thermal stability, mobility, aqueous dispensability and UV resistance were improved significantly.

The effect of the amount of silica fume on the thickness of the organic pigment layer and the effect of the thickness of the organic pigment layer on the properties of the modified pigment need to be studied further.

This paper shows a feasible method of the modification of the PR170 with the silica fume, and the modification can improve the properties of the PR170. The use of silica fume to modify organic pigment can realise the reuse of solid waste and reduce the production cost of the organic pigment.

This modification method of the organic pigment is adaptive and it can be adjusted to the modification of other species of the organic pigment.

The modification of the PR170 with the silica fume was carried out in its preparation process, which synchronised the preparation and modification of the organic pigment. The properties of the modified pigment were improved, which were beneficial for their application in inks and coatings.

Melting, fusion and solidification are the principal mechanisms used in selective laser melting to produce a product. Several thermal phenomena occur during the fabrication process, such as powder melting, melt pool formation, mixing of materials (fusion), rapid solidification, re-melting, high thermal gradient, reheating and cooling. These phenomena result in several types of pores, defects, irregular surfaces, bending and residual stress. This paper aims to focus on the physical behaviors of Ti-6Al-4V alloy at several scanning speeds and their effect on porosity and metallurgical properties.

Seven scanning speeds between 150  and 1000 mm/s were chosen to observe the occurrence of different pores, defects and microstructural formations and their effect on hardness and tensile properties.

The various mentioned malformations occur due to the results of possible uncertainties during the melting-fusion-solidification process. Size, shape, number, location and content of the pores varied in different samples. The a cicular a' size changes with different scanning speeds. Eventually, both porosity and microstructure have shown influential consequences on the hardness and tensile properties in the samples manufactured with different scanning speeds.

This study showed the adverse effects of different physical behaviors that occurred during the fabrication process, leading to the formation of complex pores. The causations and plausible solutions of the pore formation are interpreted in this paper. The authors observe that a circular a' size differed with scanning speeds, and these influence the mechanical properties.

This study aims to examine the evolution of spatial–temporal patterns in China’s hotel industry from 1978 to 2018.

A database comprising over 140,000 hotels with more than 30 rooms was created. The exploratory spatial–temporal data analysis (ESTDA) method, based on space–time cube model, was used to explore and visualize the spatial–temporal pattern of hotels.

The Chinese hotel industry can be divided into two development stages, namely, a large hotel-dominant stage before 2000 and a small–medium-sized hotel-dominant stage after 2000. China’s prefecture-level cities were clustered into four tiers. The higher the tier, the earlier the city will initiate hotel development. The Chinese hotel industry has four continuous hotspots (the Yangtze River Delta, Pearl River Delta, Bohai Rim and Sichuan and Chongqing) and some temporary hotspots.

This study lacks quantitative investigation, which could show the underlying mechanism of the evolution of the Chinese hotel industry.

This study is the first to investigate China’s hotel evolution over 40 years by applying big data and the ESTDA method. The systematic and evolutionary exploration will enable hotel researchers to understand the spatial–temporal nature of hotel distribution better. Introducing the ESTDA method into tourism and hotel research also provides an additional tool to researchers. Hotel investors and operators, city and tourism planners and market regulators can learn from the evolution of location patterns to make better where and when decisions.

This paper aims to illustrate the logics that have shifted in the Chinese hotel industry since 1949 and discuss its implications for advance a better understanding of how and why the Chinese hotel industry has evolved into its present situation. The logic evolution and future trends in this market were also discussed.

As this research is aimed at answering the “how” and “why” aspects in the evolution of Chinese hotel industry, qualitative approach is applied to answer the questions.

This paper divided the history of contemporary Chinese hotel industry into three stages: 1949-1977, 1978-2001 and 2002 to the present. Hotel business in each period was dominated by state logic, profession logic and market/corporation logic, respectively.

The authors applied institutional logics perspective to explore how and why China hotel industry evolved in the past 70 years.

This study aims to optimize the structure of gold-sputtered U-shaped plastic fiber sensors.

A group of U-shaped Au-sputtered plastic optical fiber sensing probes with polishing angles of 45°, 90° and 135° is prepared.

The experimental results show that the spectral response and sensitivity of the sensor at 45°polishing angle is twice that of the sensor at 90°.

Due to the limitations of laboratory temperature and equipment, the overall effect has not reached the ideal, but the expected effect has been obvious. Experiments also optimize the sensor.

Optical fiber sensing has always been an indispensable part of various fields.

Sensor optimization is of great help to the progress of technology and the development of science and technology.

The authors have no conflicts of interest to disclose.

This paper aims to employ data envelopment analysis (DEA) models to evaluate the efficiency level and the change of efficiency of the hotel industry in major Chinese cities from 2001 to 2011. The study also aims to investigate the determinants of this efficiency.

The DEA models were used to calibrate the scores of technical efficiency, pure technical efficiency and scale efficiency in each city, and the Malmquist productivity index was introduced to trace the efficiency change. Furthermore, the panel Tobit and linear regression models were applied to look into various factors contributing to efficiency scores.

The inefficiency of the hotel industry generally comes from the pure technical inefficiency. Moreover, the efficiency of the hotel industry has been considerably improved over the research period due to the change in technical efficiency. In addition, it was found that political hierarchy, degree of openness and level of tourism dependence help explain the cross-city differences in efficiency scores, whereas ownership structure dominantly contributes to the improvement of efficiency over time.

The benchmark analysis of efficiency is of great importance to cities with an unproductive hotel industry, as it helps them make critical adjustments towards the efficiency frontier.

This study represents one of the first studies to rigorously and systematically investigate the efficiency and efficiency change of the hotel industry in major Chinese cities and identify the possible factors explaining the efficiency score.