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The purpose of this paper is to present a weakly supervised learning method to perform health evaluation and predict the remaining useful life (RUL) of rolling bearings.

Based on the principle that bearing health degrades with the increase of service time, a weak label qualitative pairing comparison dataset for bearing health is extracted from the original time series monitoring data of bearing. A bearing health indicator (HI) quantitative evaluation model is obtained by training the delicately designed neural network structure with bearing qualitative comparison data between different health statuses. The remaining useful life is then predicted using the bearing health evaluation model and the degradation tolerance threshold. To validate the feasibility, efficiency and superiority of the proposed method, comparison experiments are designed and carried out on a widely used bearing dataset.

The method achieves the transformation of bearing health from qualitative comparison to quantitative evaluation via a learning algorithm, which is promising in industrial equipment health evaluation and prediction.

The method achieves the transformation of bearing health from qualitative comparison to quantitative evaluation via a learning algorithm, which is promising in industrial equipment health evaluation and prediction.

The purpose of this paper is to propose a new deep learning-based model to carry out better maintenance for naval propulsion system.

This model is constructed by integrating different deep learning algorithms. The basic idea is to change the connection structure of the deep neural network by introducing a residual module, to limit the prediction output to a reasonable range. Then, connect the Deep Residual Network (DRN) with a Generative Adversarial Network (GAN), which helps achieve data expansion during the training process to improve the accuracy of the assessment model.

Study results show that the proposed model achieves a better prediction effect on the dataset. The average performance and accuracy of the proposed model outperform the traditional models and the basic deep learning models tested in the paper.

The proposed model proved to be better performed naval propulsion system maintenance than the traditional models and the basic deep learning models. Therefore, our model may provide better maintenance advice for the naval propulsion system and will lead to a more reliable environment for offshore operations.

This study aims to perform flow simulations inside the acinus with fine alveolar pores (Kohn pores) using hexagonal cells and bottom-up geometric modeling, which enabled the elimination of invalid voids using previous top-bottom methods and spherical or circular cells.

Regular hexagonal cells were used to construct alveoli with no gaps via tessellation. Some hexagonal cells were fused to eliminate the inner boundaries to represent the structure of the bronchial tree. For the remaining hexagonal cells, the side lengths of the shared walls were adjusted to construct alveolar pores. Periodic moving boundaries with the same phase were set for all walls to describe synchronous contraction and expansion of the bronchi and alveoli.

More realistic flow characteristics in the distal lung were obtained. The effects of pore size and the mechanism of auxiliary ventilation of alveolar pores were revealed.

To the best of the authors’ knowledge, this is the first numerical simulation study on the function of multiple alveolar pores at the level of pulmonary acini, which will be helpful for simulating the dynamic process of cough and sputum excretion in the future.

The purpose of this paper is to investigate the relationship between union practices and two types of employees’ extra-role behaviors, namely, union citizenship behavior (UCB) and employee voice (EV), and the mechanisms that mediate this relationship.

Using matched data from 46 union leaders and 279 union members of 33 workplaces in China, this study utilized multilevel structural equation modeling to test the cross-level influences of union practices on employees’ extra-role behaviors and the mediation effects.

The results show that (1) union practices have a positive impact on employees’ UCB and EV, and (2) union practices increase UCB and EV through the improvement of industrial relations (IR) climate at the workplace level, as well as union commitment (UC) and union instrumentality (UI) at the individual level.

Although the authors collected data from multi-sources (i.e. union leaders and members), the cross-sectional data of this study limited the ability to make casual inferences.

This study contributes to the literature by providing theoretical explanation and empirical evidence to illustrate the role of union practices in increasing the extra-role behaviors of employees (i.e. UCB and EV). This is of particular importance in elaborating the effectiveness of enterprise unions under the recent reforms in China. In addition, the authors also unpacked the antecedents of extra-role behaviors in the union context by investigating how IR climate, UC and UI mediate the relationship between union practices and extra-role behaviors of employees.

We examine how social exclusion and temporal distance (i.e. being socially excluded in the present or the anticipation of exclusion in the future) shape whether people choose hedonic or utilitarian products.

We conduct four experiments to test the hypotheses. Study 1a and study 1b provide the initial evidence that consumers strategically engage in differentiation in response to social exclusion in the present and in the future. Study 2 and study 3 replicate the basic interaction effect of social exclusion and temporal distance on product choices and test the underlying mechanism.

We find that temporal distance affects consumer product choices through people’s coping strategies. When consumers are socially excluded, they are more likely to have a problem-solving tendency and more likely to choose utilitarian products. In contrast, when consumers imagine being socially excluded in the future, they are more likely to have to use emotions to solve problems and choose hedonic products.

Our study contributes to the literature in several ways. First, it deepens our understanding of the psychological drivers of social exclusion in consumer research. Second, it offers insights into understanding prior findings that document both problem-solving and emotion-regulating behavior in response to social exclusion. Third, by showing that social exclusion and temporal distance can influence the type of products selected, our findings contribute to a new stream of work that examines the impact of people’s fundamental desire for control on consumer behavior.

The purpose of this paper is to identify and evaluate faculty and academic staff perceptions, experiences and expectations with respect to a voluntary, bilingual peer assisted learning (PAL) program, which operates for the benefit of students studying in the Faculty of Business at a regional Australian University.

A survey instrument and semi-structured interviews were used to faculty executive and academic staff in order to collect information about the perceived benefits of the program and identify opportunities for improvement.

Based on an analysis of student results, the bilingual PAL program is shown to have a positive effect on performance of students participating in the program. Results from interviews with executive and academic staff indicate a high level of support for this type of student learning program.

Although the value of both bilingual teaching and PAL has been explored in the teaching and learning literature, few studies have examined the integration of these two approaches. This research contributes to the literature by exploring the practical contribution of integrating these approaches. This research also provides valuable information regarding executive and academic perceptions of PAL programs, which is infrequently addressed in the literature. Findings may be used to inform institutions of the value of bilingual PAL programs in relation to international student retention and learning support and provide a starting point for discussions around the practical implications of such programs.

In order to systematically grasp the changes and matching characteristics of wheel and rail profiles of high speed railway (HSR) in China, 172 rail profile measurement points and 384 wheels of 6 high-speed electric motive unites (EMUs) were selected on 6 typical HSR lines, including Beijing–Shanghai, Wuhan–Guangzhou, Harbin–Dalian, Lanzhou–Xinjiang, Guiyang–Guangzhou and Dandong–Dalian for a two-year field test.

Based on the measured data, the characteristics of rail and wheel wear were analyzed by mathematical statistics method. The equivalent conicity of wheel and rail matching in a wheel reprofiling cycle was analyzed by using the measured rail profile.

Results showed that when the curve radius of HSR was larger than 2,495 m, the wear rate of straight line and curve rail was almost the same. For the line with annual traffic gross weight less than 11 Mt, the vertical wear of rail was less than 0.01 mm. The wear rate of the rail with the curve radius less than 800 m increased obviously. The wheel tread wear of EMUs on Harbin–Dalian line, Lanzhou–Xinjiang line and Dandong–Dalian line was relatively large, and the average wear rate of tread was about 0.05–0.06 mm·(10,000 km)⁻¹, while that of Beijing–Shanghai line, Wuhan–Guangzhou line and Guiyang–Guangzhou line was about 0.03–0.035 mm·(10,000 km)⁻¹. When the wear range was small, the equivalent conicity increased with the increase of wheel tread wear. When the wear range of wheel was wide, the wheel–rail contact points were evenly distributed, and the equivalent conicity did not increase obviously.

This research proposes the distribution range of the equivalent conicity in one reprofiling cycle of various EMU trains, which provides guidance for the condition-based wheel reprofiling.

The purpose of this paper is to establish a three‐dimensional service house of quality (HOQ). The new service HOQ adds a dimension of quality economics to solve the problems of economic evaluation in the process of transferring customer requirements into service characteristics by traditional HOQ.

Based on the traditional two‐dimensional HOQ, this paper constructs a three‐dimension service HOQ by adding an economic dimension into the traditional structure, so that the transformation process from customer requirements into service characteristics can be evaluated with quality economic perspective. The key concern of this new model is to balance the quality improvement and economic gain of a service. The other improvement of this paper is that it uses structural equations to present the coefficient matrix in the new HOQ model to avoid human errors in the evaluation. A case study is used to verify the effectiveness of the new model.

Quality gains and costs should be considered in service design and quality improvement. The three‐dimensional service HOQ uses the dimension of quality economics to balance customer requirements and service characteristics, which is more effective than the traditional one.

The method exposed in the paper can be used by service companies for decision making in service design and quality improvement.

This paper establishes a new three‐dimensional HOQ, by which quality economics can be effectively analyzed in service design and quality improvement.