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This research aims to provide a theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and V-shaped substrate, which also gives guidance for those complicated welding operation objects in brazing technique.

Wetting experiments were performed to measure the contact angles at different temperatures of molten Sn-3.0Ag-0.5Cu wetting on the quartz substrate with an included angle of 90°. According to the experimental results, the theoretical spreading morphology of molten solder on V-shaped substrate at corresponding temperature was simulated by Surface Evolver.

The theoretical morphology profiles of the molten solder sitting on the V-shaped substrate are simulated using Surface Evolver when the molten solder reaches spreading equilibrium. The spreading mechanisms as well as the impact of surface tension and gravity on interfacial energy of the molten solder wetting on the V-shaped groove substrate are also discussed where theoretical results agree well with experiment results. The contact area between the gas and liquid phases shows a tendency of first increasing and later decreasing. Otherwise, the spreading distance and the height of the molten solder increases as the droplet volume increases as the included angle and the contact angle are given as constants, and both the interfacial energy and the gravitational energy increase as well. This research has a wide influence on predicting the outcomes in commercial impact and also gives guidance for those complicated welding operation objects in brazing technique.

It is of very important significance in both science and practice to investigate the differences between the flat surface and V-shaped surface. Some necessary parameters including intrinsic contact angle and surface tension need to be directly measured when the droplet spreads on the flat surface. The relevant simulation conclusions on the inherent characteristics can be given based on these intrinsic parameters. Compared with the flat surface, the V-shaped substrate is chosen for further discuss on the effects of gravity on the droplet spreading behavior and the changes of apparent contact angle which can only occurs as the substrate is inclined. Therefore, this research provides theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and substrate.

The research is developed for verifying the accuracy of the model built in Surface Evolver. Based on this verified model, other researches on the spreading distance along y-axis and the contact area that are especially difficult to be experimentally measured can be directly simulated by Surface Evolver, which can provides a convenient method to discuss the changes of horizontal spreading distance, droplet height and contact area with increasing the included angle of V-shaped substrate or with increasing the droplet volume. Actually, the modeling results are calculated for supplying the theoretical parameters and technical guidance in the welding process.

This research provides theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and substrate, which has a wide influence on prediction the outcomes in commercial impact and also gives guidance for those complicated welding operation objects in brazing technique.

Surface Evolver, can also be used to discuss the structure and spreading mechanism of droplets on V-shaped substrates, which have not been discussed before.

The purpose of this study is to investigate the influence of varying concentrations of nano-SiO₂ particle doping on the structure and properties of the micro-arc oxidation (MAO) coating of 7075 aluminum alloy. This research aims to provide novel insights and methodologies for the surface treatment and protection of 7075 aluminum alloy.

The surface morphology of the MAO coating was characterized using scanning electron microscope. Energy spectrometer was used to characterize the elemental content and distribution on the surface and cross section of the MAO coating. The phase composition of the MAO coating was characterized using X-ray diffractometer. The corrosion resistance of the MAO coating was characterized using an electrochemical workstation.

The results showed that when the addition of nano-SiO₂ particles is 3 g/L, the corrosion resistance is optimal.

This study investigated the influence of different concentrations of nano-SiO₂ particles on the structure and properties of the MAO coating of 7075 aluminum alloy.

Finite element analysis of underwater transducers typically requires a high level of expertise, and the iterative process of testing various sizes, material parameters and other factors is often inefficient. To address this challenge, this paper aims to introduce underwater transducer parametric simulation (UTPS) software to streamline the design and optimization process.

The design methodology integrates the strengths of ANSYS Parametric Design Language (APDL) for parametric design with the Qt Creator framework for developing a visual interface. C++ is used to encapsulate complex, hard-to-master APDL macros and interact with ANSYS software to execute the relevant APDL macros, performing finite element analysis on the underwater transducer in the background. The results are then processed and displayed on the visual interface.

UTPS enables parametric modeling, modal analysis, harmonic response analysis and directivity analysis of underwater transducers. Users only need to input parameters into the software interface to obtain the transducer’s performance, significantly improving work efficiency and lowering the professional threshold. A prototype transducer was fabricated and tested based on UTPS results, which confirmed the accuracy of the software.

This paper presents an innovative parametric simulation tool for underwater transducers, combining finite element analysis and APDL to simplify and expedite the design process. UTPS reduces the need for specialized knowledge, cutting down on training costs, while its parametric design capabilities accelerate the design process, saving resources.

In the absence of previous work, this study investigates how the psychological contract (PC) influences the safety performance of construction workers in China.

The literature is first consulted to obtain a set of PC and safety performance measures that fits the specific situation of construction workers, which is then moderated by five construction experts. A questionnaire survey of 206 workers from 4 different construction sites is followed by a descriptive statistical analysis of the nature of the PC and level of the safety performance of the respondents. Finally, a regression analysis is used to ascertain the level of influence of the PS, and an analysis is made of the influence of PC on safety performance.

A set of PC and safety performance measures is identified that fits in the construction workers' specific situation. The PC of the respondents is found to be intact and well-performed, and their safety performance is maintained at a high level. Safety performance is highly influenced by the state of the PC, with the three dimensions of safety performance (safety result, safety compliance and safety participation) positively correlated with the three dimensions of the PC (normative, interpersonal and developmental).

Suggestions are made to improve safety production management and safety performance by providing adequate material and economic conditions, helping the workers establish good interpersonal relationships and realize their personal values.

The digital economy is profoundly transforming the manufacturing industry's fundamental concepts and value creation logic, making digital transformation (DT) strategy a crucial decision for manufacturers. And faced with increasingly severe environmental issues, DT may become an important means to achieve sustainable development. This paper mainly discusses the strategic choice of the manufacturer's DT and analyzes the impact of DT on carbon emissions.

Based on the carbon cap-and-trade mechanism, the authors have constructed two decision models to study the DT strategy of the manufacturer, further exploring the impact of the mechanism on the DT strategy and production strategy of the manufacturer. Finally, the authors discussed the effect of manufacturers' DT on their carbon emissions.

The authors found that the manufacturer should initiate DT to enhance their competitiveness, regardless of whether they are in a low digital technology scenario or a high digital technology scenario. Notably, DT can enhance the ability of the manufacturer to respond to external emergencies. In a low digital technology market scenario, both carbon emissions per unit of product and carbon price are positively affecting the digitization level of the manufacturer. In a high digital technology market scenario, the manufacturer will initiate a full degree of DT. Moreover, the impact of DT on total carbon emissions varies in markets with different levels of digital technology.

Innovatively, the authors divided the DT of the manufacturer into market scenarios with low digital technology and high digital technology. Provide the manufacturer with DT decisions according to different scenarios. At the same time, it verifies the uncertainty of DT on carbon emission and enriches the related research.

Drawing upon the cognitive-affective processing system (CAPS) framework, the current study proposes a dual-pathway model that suggests self-serving leadership has a positive influence on employee knowledge hiding. The study also examines the mediating effects of relative deprivation and emotional exhaustion, as well as the moderating effect of political skill, to provide a comprehensive understanding of these relationships.

This study employed two-wave time-lagged survey data collected from 644 employees in 118 teams within a company based in Shenzhen, China. Moreover, hierarchical linear modeling (HLM) was used to test the hypothesized relationships.

The results indicated that self-serving leadership positively influenced employee knowledge hiding, and this relationship was mediated by relative deprivation and emotional exhaustion. Additionally, political skill was found to negatively moderate both the direct relationship between self-serving leadership and relative deprivation and emotional exhaustion, and the indirect path from self-serving leadership to employee knowledge hiding through relative deprivation and emotional exhaustion.

This study makes a unique contribution to the knowledge management literature in several ways. First, it introduces self-serving leadership as a predictor of employee knowledge hiding, expanding the current understanding of this phenomenon. Second, it offers a novel conceptualization, suggesting that employees coping with self-serving leadership may experience relative deprivation and emotional exhaustion, and these factors can predict their engagement in knowledge hiding. Third, the research findings on the moderating role of political skill push the boundaries of the knowledge-hiding literature, providing new insights into the conditions under which this behavior occurs.

The purpose of this paper is to examine the joint congruence effect of leadership styles and organizational culture on project members’ innovative behaviors in the construction projects setting.

The proposed hypotheses are tested using polynomial regression with a sample of 217 project managers and employees of different construction projects in China, and plotted through response surface analysis.

The results of polynomial regressions support the congruence effect hypothesis, indicating that more innovative behaviors of the project members could be elicited by a high level of congruence between transformational or transactional leadership styles and organizational culture. Furthermore, asymmetrical incongruence effects are found wherein project members with lower levels of innovative behaviors when project organizational culture is stronger as compared with when two leadership styles are at higher levels. Specifically, the condition is found under the innovation dimension of organization culture, but higher level of innovative behavior conversely displays when the harmony culture is weaker than two leadership styles.

The conceptual model and hypotheses are examined by analyzing cross-sectional and self-reported data collected in China. The findings could be further examined through multi-source or longitudinal, more systematic research.

The findings highlight the pivotal role played by the value congruence of leaders-organizations in motivating employees to be innovative in project organizations. This paper provides knowledge for project managers to help them understand whether and how project members’ innovative behaviors are better motivated by the fit or misfit between the styles of leadership and project organizational cultures. Besides, this study provides the approach or direction for the project leaders training.

This study is one of the first to examine the joint effects of leadership styles and organizational culture on innovative behavior based on the person-organization fit theory and from the perspective of value congruence.

Drawing upon ego depletion theory, the authors developed a serial mediation model linking job insecurity with employee political behavior in which resource depletion and moral disengagement operated as two sequential mediators. The authors further identified employee moral identity as an important boundary condition that impacts the strength of this serial mediation effect.

Multilevel analyses were utilized to test the proposed hypotheses by analyzing a sample included 306 employees nested in 71 groups.

Results revealed that job insecurity induced resource depletion that activated moral disengagement, which in turn instigated political behavior. Furthermore, employee moral identity weakened this serial indirect effect. Specifically, this indirect effect was positive when moral identity was low, whereas did not present when moral identity was high.

Prior studies have primarily concentrated on the detrimental effects of job insecurity. However, less study has investigated how individuals proactively cope with job insecurity. The authors contribute to this stream of research by exploring whether and how job insecurity facilitates employee political behavior.

This study aims to investigate how the strength of ties (i.e. strong ties and weak ties) in megaproject networks influences project performance in terms of types of conflicts.

A questionnaire survey was undertaken with professionals in Chinese megaprojects and 445 valid responses were received. A conflict-based theoretical model was developed and tested with structural equation modeling.

The results indicated that task conflict had a constructive effect on project performance, whereas relationship conflict and process conflict had destructive effects. Both strong and weak ties positively affected project performance, and that weak ties exerted greater effects on performance. The introduction of conflicts significantly weakened the effect of strong ties on project performance. Strong ties indirectly affected project performance via task conflict and relationship conflict, whereas weak ties affected performance only through task conflict. Task conflict had a constructive effect on project performance, whereas relationship conflict and process conflict had destructive impact.

This study identified the positive effect of strength of ties on project performance as well as the constructive and destructive roles of conflicts. Furthermore, the findings provided evidence that strength of ties and conflicts were critical factors for project performance. While, there are still limitations. There are other attributes of megaproject networks, such as network nodes’ characteristics and network structure, which may influence conflicts and project performance. Future research would be conducted to explore the role of these variables. Meanwhile, because different types of conflicts may mutually transform under certain conditions, future research would also address this issue in megaprojects.

As for the management strategies, project stakeholders should know the existence of project networks, exactly assess their resource endowment, especially their external and internal relationship network. In accordance with changes of the project network, stakeholders should share knowledge and learn techniques about how to respond to relationship disturbances, thus reducing relationship conflict and process conflict. Furthermore, stakeholders should place an emphasis on fostering and reinforcing communication and trust, thus effectively resolving task conflict, ambiguity and uncertainty engendered from network ties in a megaproject network.

The main contribution of this study is threefold. First, this study will enrich the literature on strength of ties by accentuating the roles of conflicts in megaproject context. Second, this study contributes to the theoretical development of a conceptual model for explaining the interrelationships among strength of ties, conflicts and project performance. Third, this study will respond to the call “which dimension, i.e. strong ties or weak ties, is more influential” by exploring the direct and indirect effects of strength of ties on project performance.

Drawing from cognitive and emotional perspectives, the purpose of this paper is to theorize and test a dual-pathway model in which moral disengagement and anger toward organization act as two explanatory mechanisms of the association between perceived overqualification and employee cyberloafing. The authors further proposed that the strengths of these two mediating mechanisms depend on employee moral identity.

The authors used hierarchical linear modeling to examine the hypotheses by analyzing a sample of 294 employees working in 71 departments in China.

Results revealed that moral disengagement and anger toward organization mediated the positive link between perceived overqualification and cyberloafing beyond the influence of social exchange. Furthermore, moral identity attenuated the association between the mediators (i.e. moral disengagement and anger) and cyberloafing and the indirect relationship between perceived overqualification and cyberloafing.

Extant studies have examined the effects of perceived overqualification on employee behaviors in terms of task performance, organizational citizenship behavior, proactive behavior, as well as withdrawal behavior. The study expands this line of research by empirically investigating whether and how perceived overqualification influences cyberloafing.