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Graded honeycombs are materials that exhibit better energy absorption performance compared to uniform honeycombs without adding additional weight. This paper introduces a novel modularized graded honeycomb into a commercial crash box to improve its crashworthiness.

A modularized graded honeycomb is inserted into a commercial crash box to develop a novel crash box. Finite element analyses are conducted to investigate the crashworthiness. Pareto cumulative influence analysis is conducted to rank the effects of design parameters on crashworthiness. A surrogate model-based multi-objective optimization is carried out to improve energy absorption while limiting the impact peak force. An optimal Pareto solution set is obtained.

Modularized honeycomb-filled crash box outperforms that of its corresponding uniform honeycomb-filled crash box and empty crash box in resisting impact. Pareto cumulative influence analysis reveals that for most crashworthiness indicators, cell-wall thicknesses of crash box tube contribute the most, followed by average relative density and graded coefficient of modularized honeycomb (MH). Graded coefficient contributes nearly 10% on mean force and maximum displacement, but it has insignificant influence on peak force and weight. Optimization results show that the optimal designs can not only absorb more energy but also limit the peak force compared with those of uniform honeycomb-filled crash box.

This paper fills a MH into a commercial crash box to propose a novel crash box and demonstrates the positive impact of modularized design on crashworthiness compared with that of uniform honeycomb-filled crash box. Moreover, modularizing honeycomb does not change the weight of the filler, and thus, the novel crash box would benefit development of crash box with lightweight and excellent energy absorption capacity.

Auxetics metamaterials show high performance in their specific characteristics, while the absolute stiffness and strength are much weaker due to substantial porosity. This paper aims to propose a novel auxetic honeycomb structure manufactured using selective laser melting and study the enhanced mechanical performance when subjected to in-plane compression loading.

A novel composite structure was designed and fabricated on the basis of an arrowhead auxetic honeycomb and filled with polyurethane foam. The deformation mechanism and mechanical responses of the structure with different structural parameters were investigated experimentally and numerically. With the verified simulation models, the effects of parameters on compression strength and energy absorption characteristics were further discussed through parametric analysis.

A good agreement was achieved between the experimental and simulation results, showing an evidently enhanced compression strength and energy absorption capacity. The interaction between the auxetic honeycomb and foam reveals to exploit a reinforcement effect on the compression performance. The parametric analysis indicates that the composite with smaller included angel and higher foam density exhibits higher plateau stress and better specific energy absorption, while increasing strut thickness is undesirable for high energy absorption efficiency.

The results of this study served to demonstrate an enhanced mechanical performance for the foam filled auxetic honeycomb, which is expected to be exploited with applications in aerospace, automobile, civil engineering and protective devices. The findings of this study can provide numerical and experimental references for the design of structural parameters.

The purpose of this paper is to examine how relative abusive supervision (i.e. team member’s perceived abusive supervision as compared with the team mean) influences team member’s job attitudes through the mediating role of relative leader–member exchange. This study also explores the cross-level moderating roles of team-level abusive supervision and team-level leader–member exchange (LMX) in the process.

This study used two-wave data from 1,479 employees in 145 work teams, and tested a cross-level moderated mediation model using multilevel structural equation modeling.

Results demonstrate that the negative indirect effects of relative abusive supervision on job satisfaction and team affective commitment through relative LMX are stronger when team-level abusive supervision is low rather than high.

Integrating LMX theory with a relative deprivation perspective, this study conceptualizes and operationalizes relative abusive supervision, develops an individual-within-group model of abusive supervision’s consequences in teams and demonstrates a cross-level moderating effect of team-level abusive supervision in buffering relative abusive supervision’s negative consequences.

The authors propose a new motivation construct, political self-efficacy, and investigate how and when leader political mentoring influences follower political behavior and promotability through political self-efficacy.

The authors collected four samples to develop a scale for political self-efficacy and conducted two field studies of leader-follower dyads to examine the model.

Leader political mentoring enhances followers' political behavior and promotability through increasing their political self-efficacy. These positive indirect effects are stronger when followers have a higher positive political perception.

This study integrates mentoring research with organizational politics literature and theorizes how a domain-specific self-efficacy—political self-efficacy, translates the positive impact of leader political mentoring on constructive behavioral and career-related outcomes.

With the massive use of fossil energy polluting the natural environment, clean energy has gradually become the focus of future energy development. The purpose of this article is to propose a new hybrid forecasting model to forecast the production and consumption of clean energy.

Firstly, the memory characteristics of the production and consumption of clean energy were analyzed by the rescaled range analysis (R/S) method. Secondly, the original series was decomposed into several components and residuals with different characteristics by the ensemble empirical mode decomposition (EEMD) algorithm, and the residuals were predicted by the fractional derivative grey Bernoulli model [FDGBM (p, 1)]. The other components were predicted using artificial intelligence (AI) models (least square support vector regression [LSSVR] and artificial neural network [ANN]). Finally, the fitting values of each part were added to get the predicted value of the original series.

This study found that clean energy had memory characteristics. The hybrid models EEMD–FDGBM (p, 1)–LSSVR and EEMD–FDGBM (p, 1)–ANN were significantly higher than other models in the prediction of clean energy production and consumption.

Consider that clean energy has complex nonlinear and memory characteristics. In this paper, the EEMD method combined the FDGBM (P, 1) and AI models to establish hybrid models to predict the consumption and output of clean energy.

With the rise of digital construction, using organizational capabilities to improve project performance in a turbulent environment has become critical for the high-quality development of the construction industry. However, the complex relationships among them remain unclear. Therefore, this study explores these linear relationships under the digital construction mode and reveals the driving mechanism of multi-factor linkage on project performance.

Data were collected from 263 project participants in digital construction projects in China using a questionnaire. Hypothesis testing was conducted using partial least square structural equation modeling, and the differentiated patterns of project performance formation were revealed through fuzzy-set qualitative comparative analysis.

Organizational information technology, innovation, coordination, integration management and emergency management capabilities improve project performance. Environmental turbulence is a positive moderator between coordination capabilities and project performance, while other capabilities do not align with environmental turbulence. The research obtained five equivalent configurations for achieving high project performance, such as “capability layout” and “internal driven,” and two paths that lead to non-high project performance. Finally, in contrast to existing studies, we discovered the outstanding contribution of emergency management capabilities to project performance and the auxiliary effect of information technology capabilities.

This study innovatively integrates a dimensional framework of construction project organizations’ capabilities under a digital construction mode and extends the organizational capabilities to the specific and operational capability dimension level. Furthermore, this study opens the “black box” of the influence of organizational capabilities on project performance in environmental turbulence and reveals the differentiated and equivalent configurations for the formation of project performance. The study broadens the theoretical perspective of organizational capabilities on project performance research in the digital context and provides practical enlightenment for guiding the capability configuration of construction project organizations in a turbulent environment. The study broadens the theoretical perspective of organizational capabilities on project performance research in the digital context and provides practical enlightenment for guiding the capability configuration of construction project organizations in a turbulent environment.

The purpose of this paper is to introduce the concept of time lag to grey system models, and propose the grey system models with time lags.

The models were applied to calculate the time lags between spring flow and precipitation (i.e. hydraulic response time) and simulate karst spring discharge in Liulin Springs Basin, China.

The results show that the time lags of Lishi, Zhongyang, and Fangshan are three, five, and eight, respectively. By considering the time lags, we set up the grey system GM(1,4) response model of Liulin Springs discharge to precipitation of Lishi, Zhongyang, and Fangshan.

The results are in agreement with regional geological structure and provide a better understanding of karst hydrological processes of Liulin Springs Basin.

The purpose of this paper is to reveal the identification-based mechanisms through which servant leadership affects desired outcomes (organizational citizenship behavior (OCB) toward coworkers and turnover intention) in the service industry in China.

The data of 293 pairs of valid subordinate-supervisor dyads were collected from the hospitality industry in China with a time lag of 30 days to reduce common method bias. Hypotheses were tested by a bootstrapping method and rival model comparisons.

The authors demonstrate that both the subordinate’s identification with the supervisor and identification with the organization play crucial roles in translating servant leadership’s effects to subordinate’s coworker-oriented OCBs and turnover intention. However, the occurrence of the two identifications seems to be not parallel but in sequence (i.e. pointing from identification with the supervisor to identification with the organization). In addition, results show that servant leadership’s ability to reduce subordinate’s fear of being close to the immediate supervisor is an equally significant route through which subordinate’s identification with the organization can be established.

The research has extended the literature and provided a nuanced explanation of the identification processes underlying servant leadership. The differentiation between relational identification with supervisor and collective identification with organization has shed light on a socialization mechanism through which subordinates come to demonstrate other-oriented service behavior and choose not to leave the organization. Additionally, the way that servant leadership helps eliminate subordinate’s fear in a supervisory relationship has proved to be in-negligible in enhancing organizational identification.

The purpose of this paper is to describe the tribological characteristics with different area density of concave-convex micro-texture on the mold surface. It is a new technology to improve the quality of the workpiece to control the tribological properties through the application of concave-convex micro-texture on the mold surface.

Five groups of laser micro-texture with different area density (ratio of the concave-convex micro-texture area to the all-area) were processed on the surface of the mold steel, and the tribological properties were compared with the smooth surface of the reference sample.

The time of the running-in stage in different experimental groups was about 300 s. The fluctuation amplitude of concave-convex micro-texture friction coefficient is much larger than that of smooth plane specimen in the running-in stage. After the running-in stage, the friction coefficients were lower than that in the smooth condition and decreased with the increase of the concave-convex micro-texture area density. When the area density reached 25%, the friction coefficients no longer decreased significantly. In addition, the wear of concave-convex micro-texture surface is much lower than that of smooth surface and decreases with the increase of concave-convex micro-texture area density.

Domestic and foreign scholars have done a lot of research on the relationship between concave micro-texture and tribological properties. However, the object of this paper is a new concave-convex micro-texture, which is rarely studied in the field of tribology.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2020-0081/

Concerning that limited explanation exists examining the function of corporate governance in trust processing within entrepreneurial network development, the purpose of this paper is to explore trust evolution and the role of corporate governance in an entrepreneurial network.

This paper makes an innovative exploration based on the case study of NVC Lighting Holding Limited.

It proposes that in the initial period of network relationship which is based on entrepreneur’s individual social network and embodies sole social network embeddness, entrepreneurial network relies more on affective trust than contractual trust. When stepping into extending period of network relationship which reflects separate embeddedness of social and market network, however, entrepreneurial network has an equal reliance on both affective trust and contractual trust. With further development, when ushering in the phase of maturity which undergoes superimposing embeddedness of both social and market network, entrepreneur network inclines to rely more heavily on affective trust than contractual trust. During the whole process, it can be found that the reliance of entrepreneurial network on trust has the tendency to transfer from affective trust to contractual trust. Furthermore, decreasing of equity ratio of founders and strengthening of controlling right heterogeneity in the corporate governance have facilitated the transfer process and the entrepreneurs’ authority has restraining effect on the evolution of the process.

Through case study, this paper presents the trust evolution process in different stages of entrepreneurial network. Another important theoretic contribution of this paper is that it reveals the function of corporate governance in trust processing within entrepreneurial network development.