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This paper aims to investigate the equivalent relationship between accelerated corrosion tests and real environmental spectrum of suspenders in long-span suspension bridge considering multiple factors action.

Based on Faraday's law, corrosion current was used as a measure of metal corrosion, and the equivalent conversion relationship between laboratory environment and real service environment was established. The equivalent conversion method for bridge structural steel had been determined under different temperature, humidity, pH value and NaCl concentration conditions. The compilation of environmental spectra for large span bridges considering multiple factors and the principle of equivalent conversion have been proposed.

Environmental factors, including temperature, humidity, pH value and NaCl concentration, have significant impact on the corrosion degree of suspension steel wires, and only considering these two factors for equivalent conversion cannot accurately reflect the true service environment of the bridge. The 33.8-h salt spray accelerated corrosion test using the standard conditions can be equivalent to one year of suspenders corrosion in a real service environment.

The equivalent accelerated corrosion method for steel wires proposed in this study can effectively predict the corrosion degree of the suspenders, which has been verified to be correct and can provide theoretical guidance for the development of corrosion test plans for steel wires and engineering technical basis for anti-corrosion control and calendar life research of suspension bridge suspenders.

The purpose of this paper is to propose and demonstrate a new additive manufacturing approach that breaks the layer-based point scanning limitations to increase fabrication speed, obtain better surface finish, achieve material flexibility and reduce equipment costs.

The freeform additive manufacturing approach conceptually views a 3D article as an assembly of freeform elements distributed spatially following a flexible 3D assembly structure, which conforms to the surface of the article and physically builds the article by sequentially forming the freeform elements by a vari-directional vari-dimensional capable material deposition mechanism. Vari-directional building along tangential directions of part surface gives surface smoothness. Vari-dimensional deposition maximizes material output to increase build rate wherever allowed and minimizes deposition sizes for resolution whenever needed.

Process steps based on geometric and data processing considerations were described. Dispensing and forming of basic vari-directional and vari-dimensional freeform elements and basic operations of joining them were developed using thermoplastics. Forming of 3D articles at build rates of 2-5 times the fused deposition modeling (FDM) rate was demonstrated and improvement over ten times was shown to be feasible. FDM compatible operations using 0.7 mm wire depositions from a variable exit-dispensing unit were demonstrated. Preliminary tests of a surface finishing process showed a result of 0.8-1.9 um Ra. Initial results of dispensing wax, tin alloy and steel were also shown.

This is the first time that both vari-directional and vari-dimensional material depositions are combined in a new freeform building method, which has potential impact on the FDM and other additive manufacturing methods.

Wind energy has become a distinguished field of energy among the alternative energy resources. Despite economical disadvantages, the production of wind energy is desired to fulfill the demand of the energy. Low reliability is a big issue in the development of wind energy technology that has affected wind farm operations. The purpose of the study is to find the reason for the low reliability and high downtime for wind turbines.

The systems engineering approach has a high success rate in handling complex systems such as wind farms. A failure finding model is presented based on the systems engineering, with the focus to analyze the failures at the interfaces. The required data have been collected by reviewing the literature.

Gear box interfaces are a vital reason for the higher downtime and frequent failures of wind turbines, and the bearing and the lubricant in the gear box are affected because of their inappropriate combination.

The reliability and the maintainability of the wind turbine is a topic of major importance. The study is an attempt to contribute to a more sophisticated solution to the reliability problem of the wind turbine. Moreover, it shows the importance of interfaces in designing the complex systems.

The purpose of this paper is to investigate the effect of boundary slip on hydrodynamic performance of liquid film seal considering cavitation.

A mathematical model of liquid film seal with slip surface was established based on the Navier slip model and Jakobsson–Floberg–Olsson (JFO) boundary condition. Liquid film governing equation was discretized by the finite difference method and solved by the SOR relaxation iterative algorithm and the hydrodynamic performance parameters of liquid film seal were obtained considering boundary slip and cavitation.

The results indicate that the values of performance parameters are affected significantly by the slip length under the condition of high speed and low differential pressure.

The performances of liquid film seal are investigated considering slip surface and cavitation. The results presented in the study are expected to provide a theoretical basis to improve the design method of liquid film seal.

The purpose of this paper is to provide an updated and theory-driven meta-analysis of work–family conflict (WFC). The authors quantitatively review the relationships between WFC and three pairs of antecedents and several consequences.

A meta-analysis was conducted to investigate the research model. Specifically, the authors adopt a resource-based perspective (i.e. conservation of resources (COR) theory) to investigate the relationships between three pairs of antecedents (demand/control, autonomy/hours spent at both work and family domains and role overload/flexibility) and WFC. While COR theory argues that resource loss perceptions would generate much more influential impact on individuals comparing to that of resource gain, both favourable and unfavourable antecedents, representing resource gain and resource loss, respectively, are incorporated in each pair of antecedents. This inclusion of contrary antecedents allows the authors to investigate the comparison of the relationships between the favourable antecedents – WFC relationships and the unfavourable factors – WFC relationships. In addition, the authors analyse how and to what extent WFC influences employees’ attitudes (i.e. commitment), behaviours (i.e. performance) towards both work and family, and their career consequences.

The meta-analytical findings generally support the hypotheses. Work and family demands are found positively related to WFC, while having a control at either work or family would be negatively related to WFC. Perceiving a high level of autonomy at work is negatively related to WFC, and hours spend at work has a positive relation with WFC. Role overload at both work and family are associated with WFC, while having flexibility from work schedule would be negatively related to WFC. In addition, WFC is negatively related to employee career development outcomes.

First, the authors adopt a resource-based view to organise both favourable and unfavourable antecedents of WFC. Second, this paper aims at extending the investigation on WFC consequences to performance at both work and family, commitment to both work and family, and employee career outcomes, because all of them are critical consequences but not fully explored in previous meta-analyses. Third, this paper has incorporated newly explored correlates of WFC (e.g. employee career development-related outcomes) and quantitatively reviewed their relationships with WFC.

The poor corrosion resistance of the ferrite-pearlite steel limits its application in marine engineering because of the enhanced galvanic effect caused by continuously accumulated cementite. Cr as one principal alloying element is commonly used to improve the corrosion resistance of steels. This paper aims to study the effect of Cr on corrosion behaviors of ferrite-pearlite steels in an acidic environment.

The tested steels were immersed in a simulated solution of 10 Wt.% NaCl with pH 0.85 for 72 h to evaluate the corrosion rate. After the immersion test, the corrosion morphologies and products were tested by scanning electron microscopy, energy dispersive X-ray analysis and X-ray diffraction. Meanwhile, an electrochemical workstation was used to study the electrochemical behaviors of samples.

At the initial corrosion stage, the corrosion rate increased in the sequence of Cr₀, Cr_0.5 and Cr₁ steels, which was because of the competitive effect between the area ratio and the driving force caused by alloyed Cr. However, Cr₁ steel exhibited the best corrosion resistance after a 72-h immersion test. This was because the alloyed Cr promoted the formation of protective Fe₂O₃ and FeCr₂O₄, which suppressed the preferential dissolution of ferrite and, thus, reduced the accumulation rate of carbides, resulting in the weakened galvanic corrosion.

This paper reports the role that Cr plays in the galvanic corrosion of ferrite-pearlite steels, which is important for the engineering application of ferrite-pearlite steels in marine environment.

The purpose of this study was to conduct a comprehensive analysis of the impact and its mechanism on the transfer of agricultural labor forces in the surrounding areas resulting from the establishment of a natural reserve, which holds great significance. The significance of this analysis is on the ecological protection of the natural reserve and the coordinated development of local social economy.

This study first performs an analysis on the impact and its mechanism on the establishment of the natural reserve on the transfer of agricultural labor forces from two aspects, which are push and pull factors. Then, based on county panel data in Jiangxi Province from 1995 to 2012, this study builds a generalized difference-in-difference model and performs an empirical study on the impact, heterogeneity and its mechanism on the establishment of the natural reserve on the transfer of agricultural labor forces.

The empirical analysis reveals that the establishment of natural reserves would significantly promote the transfer of agricultural labor forces to non-agricultural sectors. The robust test and placebo test with changed estimation methods verify the robust of the result. The result passes the parallel trend test and shows that the impact is most significant within one year after the implementation of the policy. From the mechanism analysis, the impact mainly comes from the “push” effect brought by the restricted development of agricultural production and primary industry on agricultural labor forces, and the “pull” effect brought by the development of local tertiary industry.

The conclusion of this study enriches the understanding of the internal mechanism between the establishment of natural reserves and the transfer of agricultural labor forces from the push and pull factors, and can provide reference for formulating policies to promote the coordinated development of natural reserve construction and regional social economy.

The purpose of this paper is to study the influence of alkyl chain length and kind of anions of ionic liquids on the tribological properties with different materials as friction pairs (steel-aluminum, steel-copper and steel-Si3N4 ceramic).

Tribological properties were evaluated by an optimol-SRV-IV reciprocation friction tester with a ball-on-block configuration at room temperature and high temperature, respectively. Friction-reducing and anti-wear properties of the ionic liquids for steel/aluminum, steel/copper and steel/ceramic contacts were evaluated on the ball-on-block reciprocating UMT-2MT tribometer. The morphologies of the worn surfaces were observed by a scanning electron microscope. The chemical states of several typical elements on the worn surfaces were examined by X-ray photoelectron spectroscopy.

Both the alkyl chain length and kind of anion influence the tribological properties of ionic liquids, especially for the length of alkyl chains. With the increase of alkyl chain length, the load carrying capacity of ionic liquids is improved at both room temperature and high temperature, and the friction reducing and antiwear behaviors are also significantly enhanced.

The paper presents potentially useful and highly efficient lubricants.

Owing to their good friction-reducing and wear resistance properties, these ionic liquids are promising candidates for versatile applications.

This work might provide a promising research direction for design and application of ionic liquids as lubricants.

More enterprises adopt open innovation by breaking technological or organizational boundaries to seek internal and external knowledge when they face a fiercely competitive environment, complex market demands, and increasingly rapid technological change. In this context, a knowledge search strategy is regarded as an effective means of obtaining inside and outside resources and an important way to break the innovation bottleneck. Moreover, information technology (IT) is deemed an important asset for sourcing knowledge, whereas absorptive capacity is seen as an indispensable ability for utilizing novel knowledge. Thus, this paper aims to test the role of knowledge search in open innovation and examine the mediating effect of absorptive capacity and the moderating effect of IT capability.

Using a sample of 1,088 Chinese firms’ data collected by the World Bank in 2012, this paper employs logistic regression to test the hypotheses.

This study finds that local and boundary-spanning search strategies positively influence both product and process innovation, and absorptive capacity has a mediating role in the relationships between knowledge search and product and process innovation. Moreover, IT capability has a positive moderating effect on the relationship between local search and innovation performance; however, IT capability strengthens the relationship between boundary-spanning search and process innovation while weakens that between boundary-spanning search and product innovation.

This study explores the impact of different knowledge search behaviors on different types of innovation and probes the role of absorptive capacity and IT capability in mediating and moderating the above relationships. By drawing on knowledge-based theory and cognitive-developmental theory, this paper provides a novel perspective to explain the mechanism between knowledge search and innovation performance.

The purpose of this study is to understand how ethical leadership and coworker ethical behavior will influence employee unethical pro-organizational behavior (UPB). In particular, the authors examine the mediating effect of moral disengagement on the relationship between ethical leadership and UPB and also investigate the moderating effect of coworker ethical behavior on the aforementioned effect.

Data were collected from 251 employee–coworker dyads from five organizations in Taiwan at two time points. Moderated mediation analysis was conducted to test the hypotheses.

The results show that moral disengagement mediates the relationship between ethical leadership and employee UPB. Moreover, the results show that coworker ethical behavior moderates the relationship between moral disengagement and employee UPB, as well as the mediated relationship between ethical leadership and employee UPB via moral disengagement. Specifically, both the moral disengagement–UPB relationship and the ethical leadership–moral disengagement–UPB relationship become weaker when coworker ethical behavior is high.

The results highlight the importance of creating an ethical work environment to get everyone behaving ethically in the workplace, because nurturing an ethical atmosphere in organizations will be useful in reducing the occurrence of UPB even for those who have high levels of moral disengagement.

This study shows that coworkers matter morally as much as leaders, demonstrating the importance of social influence from coworkers in organizations.