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Ion‐acoustic wave propagation in plasma is discussed. Analytical and numerical solutions are given for one‐dimensional plane waves. The similarity of the ion‐acoustic waves to the waves associated with an electrical transmission line is pointed out and the solved examples are compared with experimental observations.

This paper aims to introduce the decomposed harmonic balance finite element method (HBFEM) to decrease the memory requirement in large‐scale computation of the DC‐biasing magnetic field. Harmonic analysis of the flux density and flux distribution was carried out to investigate the DC biased problem in a laminated core model (LCM).

Based on the DC bias test on a LCM, the decomposed HBFEM is applied to accurately calculate the DC‐biasing magnetic field. External electric circuits are coupled with the magnetic field in the harmonic domain. The reluctivity matrix is decomposed and the block Gauss‐Seidel algorithm solves each harmonic solution of magnetic field and exciting current sequentially.

The calculated exciting currents and flux density are compared with that obtained from measurement and time domain finite element analysis, respectively, which demonstrates consistency. The DC bias leads to the significant saturation of the magnetic core and serious distortion of the exciting current. The flux density varies nonlinearly with DC bias excitation.

The harmonic balance method is only applicable in solving the steady state magnetic field. Future improvements in the method are necessary in order to manage the hysteresis effects in magnetic material.

The proposed method to solve the DC biased problem significantly reduces the memory requirement compared to the conventional HBFEM. The decomposed harmonic balance equations are solved efficiently by the block Gauss‐Seidel algorithm combined with the relaxation iterative scheme. An investigation on DC bias phenomena is carried out through the harmonic solution of the magnetic field. The decomposed HBFEM can also be applied to solve 3‐D DC‐biasing magnetic field and eddy current nonlinear problems in a practical power transformer.

User resistance to change has been identified as a significant cause of information system (IS) implementation failure. Previous studies have proposed antecedents of user resistance to change. However, whether project leadership (e.g. authoritarian leadership) can lead to user resistance to change remains unclear. By drawing on project leadership, affective event theory and contingency theory of leadership, the authors address this void by empirically examining whether authoritarian leadership can lead to user resistance to change through the mediation of negative emotion and whether the magnitude of this mediation depends on the power distance level.

This study examines the authors’ research model that integrates authoritarian leadership, negative emotion, power distance and user resistance to change using data from a matched-pair survey of 278 users and their supervisors involved in IS project implementation in China.

Negative emotion plays a mediating role in the relationship of authoritarian leadership and user resistance to change. In addition, power distance moderates the relationship between authoritarian leadership and negative emotion and the indirect effect of authoritarian leadership on user resistance to change in IS project implementation through negative emotion.

The authors’ research provides a comprehensive understanding of the antecedents of user resistance to change in IS project implementation and ultimately contributes to the IS project implementation literature and practice.

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.

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.

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.

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.

The effect of SBF artificial body fluid on microstructure and morphology characteristics of AZ91D alloy was investigated using OM, SEM and XRD. The effect of corrosion on mechanical properties also was researched.

The results show that the corrosion weight loss rate initially increased, then clearly decreased, and finally remained steady. Pits began to appear when the sample was placed in a corrosive environment for five days and pitting gradually increased with longer exposure time.

The pits, which made the grain boundaries indistinct, first appeared near the grain boundary area and then gradually increased in area.

The main mode of corrosion is pitting and the primary corrosion product, MgOH2, could be observed after five days of corrosion.

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.

This paper aims to prevent gasket sealing failure in engineering, accurately predict gasket life, extend system life and improve sealing reliability. The accelerated life test method of flexible graphite composite–reinforced gaskets is established, the life distribution law of flexible graphite composite–reinforced gaskets is revealed, and the life prediction method of flexible graphite composite–reinforced gaskets with different allowable leakage rates is proposed, which can provide a reference for the life prediction of other types of gaskets.

In this study, flexible graphite composite–reinforced gaskets were tested for long-term high-temperature sealing performance on a multi-sample gasket accelerated life test rig. The data were also analyzed using the least squares method and the K-S hypothesis calibration method. A gasket time-dependent leakage model and an accelerated life model were also developed. Constant stress-accelerated life tests were conducted on flexible graphite composite–reinforced gaskets. On this basis, a gasket life prediction method at different allowable leakage rates was proposed.

The life distribution law of flexible graphite composite–reinforced gaskets is revealed. The results show that the life of the gasket obeys the Weibull distribution. The time-correlated leakage model and accelerated life model of the gasket were established. And the accelerated life test method of the flexible graphite composite–reinforced gasket was established. The life distribution parameters, accelerated life model parameters and life estimates of gaskets were obtained through tests. On this basis, a gasket life prediction method under different leakage rates was proposed, which can be used as a reference for other types of gaskets.

The research in this paper can better provide guidance for the use and replacement of gaskets in the project, which is also very meaningful for predicting the leakage condition of gaskets in the bolted flange connection system and taking corresponding control measures to reduce energy waste and pollution and ensure the safe operation of industrial equipment.

A multi-specimen gasket-accelerated life test device has been developed, and the design parameters of the device have reached the international advanced level. The life distribution law of the flexible graphite composite–reinforced gasket was revealed. The accelerated life test method for the flexible graphite composite–reinforced gasket was established. The life prediction method of the flexible graphite composite–reinforced gasket under different allowable leakage rates was proposed.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2023-0254/