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This paper aims to explore a new wavelet adaptive threshold de-noising method to resolve the shortcomings of wavelet hard-threshold method and wavelet soft-threshold method, which are usually used in gear fault diagnosis.

A new threshold function and a new determined method of threshold for each layer are proposed. The principle and the implementation of the algorithm are given. The simulated signal and the measured gear fault signal are analyzed, and the obtained results are compared with those from wavelet soft-threshold method, wavelet hard-threshold method and wavelet modulus maximum method.

The presented wavelet adaptive threshold method overcomes the defects of the traditional wavelet threshold method, and it can effectively eliminate the noise hidden in the gear fault signal at different decomposition scales. It provides more accurate information for the further fault diagnosis.

A new threshold function is adopted and the multi-resolution unbiased risk estimation is used to determine the adaptive threshold, which overcomes the defect of the traditional wavelet method.

This paper aims to explore a new way to extract the fault feature of a rolling bearing signal on the basis of a combinatorial method.

By combining local mean decomposition (LMD) with Teager energy operator, a new feature-extraction method of a rolling bearing fault signal was proposed, called the LMD–Teager transform method. The principles and steps of method are presented, and the physical meaning of the time–frequency power spectrum and marginal spectrum is discussed. On the basis of comparison with the fast Fourier transform method, a simulated non-stationary signal was processed to verify the effect of the new method. Meanwhile, an analysis was conducted by using the recorded vibration signals which include inner race, out race and bearing ball fault signal.

The results show that the proposed method is more suitable for the non-stationary fault signal because the LMD–Teager transform method breaks through the difficulty of the Fourier transform method that can process only the stationary signal. The new method can extract more useful information and can provide better analysis accuracy and resolution compared with the traditional Fourier method.

Combining the advantage of the local mean decomposition and the Teager energy operator, the LMD–Teager method suits the nature of the fault signal. A marginal spectrum obtained from the LMD–Teager method minimizes the estimation bias brought about by the non-stationarity of the fault signal. So, the LMD–Teager transform has better analysis accuracy and resolution than the traditional Fourier method, which provides a good alternative for fault diagnosis of the rolling bearing.

Pyrolysis for coal gas generation changes the composition, pore structure, permeability and adsorption capacity of coal. This work aims to discuss the utilization of coal pyrolysis on enhancing coalbed methane (CBM) production in the Gujiao area, Shanxi province, China.

This research was conducted mainly by the methods of thermogravimetry mass spectrometry (TG-MS) analysis, liquid nitrogen adsorption experiment and methane isothermal adsorption measurement.

The results can be concluded as that 400-700°C is the main temperature range for generating CH₄. Pore volume and specific surface area increase with increasing temperature; however, the proportion of micro pore, transition pore and macro pore has no difference. The optimum temperature for enhancing CBM production should be letter than 600°C because the sedimentation of tar and other products will occupy some pores and fissures after 600°C.

Here in, to accurately recognize the suitable maximum temperature for heating development, a method enhancing CBM production, TG-MS, was adopted to analyze the products and the weight loss of coals with different ranks in the Gujiao area at temperature of 30-1,100°C. And then the pore structure, porosity, permeability, methane adsorption capacity and thermal maturity of coals during pyrolysis were investigated with increased temperature from 30°C to 750°C. On these bases, the favorable condition for enhancing CBM production and the thermal evolution of coal were recognized.

The purpose of this paper is to examine the impact of two typical relationship management approaches (trust relationship with suppliers and reciprocity) on manufacturer resilience in the context of the COVID-19 crisis. Moreover, this paper aims to deepen the understanding of environmental uncertainty's moderating effect on the association between the trust relationship with suppliers (TRS) and reciprocity.

Structural equation modeling has been used to test the hypotheses on 361 Chinese manufacturing firms' managers and independent directors during the COVID-19 crisis.

The results reveal that reciprocity positively enhances three dimensions of manufacturer resilience, namely, preparedness, responsiveness and recovery capability. Reciprocity positively mediates the relationships between TRS and preparedness, responsiveness and recovery capability. Moreover, environmental uncertainty moderates the association between TRS and reciprocity.

This study highlights the critical role of reciprocity, the relational governance approach, in enhancing manufacturer resilience in practice. This paper suggests that during emergencies such as the COVID-19 pandemic, managers should adopt trust and reciprocity in supplier relationship governance to strengthen the resilience of manufacturing companies and adapt effective strategies according to the environment.

This study is unique in developing new scales of manufacturer resilience through interviews and surveys with Chinese manufacturers and theoretical research. Based on the social capital theory and social exchange theory, this study shed light on the role of trust and reciprocity. It also bridges relational governance theory with the literature on manufacturing firm resilience literature to help manufacturers better understand the transdisciplinary links between relationship management and resilient operations in emergencies.

Given the importance of frugal innovation for small and medium-sized enterprises (SME) in developing countries, this study aims to explore the role of IT resources on frugal innovation through the mediating roles of knowledge sources and to what extent the relationship between sources of knowledge and frugal innovation is strengthened or weakened under the moderating effects of market turbulence.

This is an empirical study. Data were gathered from 355 SME employees of Pakistan through a questionnaire survey; the variance-based PLS-SEM approach was used to analyze the data.

Findings reveal the significant impacts of IT resources on different aspects of frugal innovation, namely, frugal functionality (FF), frugal cost (FC) and frugal ecosystem (FE). Moreover, the paper highlights the mediating roles of sources of knowledge in the relationship between IT resources and frugal innovation in frugal functionality and frugal cost. Findings also revealed that the moderation of market turbulence strengthens the effects of sources of knowledge on frugal functionality and ecosystem, but surprisingly weakens the relationship between sources of knowledge and frugal cost.

To bring a deeper understanding of the significant role of IT and knowledge sources, future research should examine the potential moderating role of environmental factors or perceived organizational support or mediating role of knowledge management processes in the relationship between IT resources and frugal innovation.

The paper provides a valuable understanding and novel approach for directors of SMEs in developing countries to improve their frugal innovation capability through IT and knowledge resources.

This study contributes to bridging research gaps in the literature and advances how IT resources, directly and indirectly, help firms improve frugal innovation capability via mediating roles of sources of knowledge.

This study empirically tests a conceptual framework that shows how integration practices are significantly associated with supply chain (SC) performance. This study also intends to achieve the following purposes: first, how the performance is influenced by the integration practices, i.e. internal and external; second, to measure the mediating effect of organizational antecedents (market orientation, learning orientation) between integration practices and firm’s SC performance.

In a noncontrived study environment, a cross-sectional study design was used with a questionnaire. The study used a stratified proportionate random sample of 205 managers from manufacturing firms in China. Six hypothesized relationships were examined using the structural equation modeling (SEM) technique in AMOS software, and five were shown to be valid. The proposed model was validated through various techniques.

Results of this study indicate that both external and internal integration influence SC performance and confirms the mediating role of organizational antecedents between integration practices and SC performance. According to the findings, five out of the six hypotheses are accepted. Findings of this research also offer very expedient insights for the companies’ management which can help them to ensure optimal output by giving due importance to external as well as internal integration.

The data for the study were only obtained from one province, which was Henan Province, and one industry, which was manufacturing; this constrained the generalizability of the study. The findings may be further validated in the future by expanding the scope of the studies to include various cultural contexts and types of businesses. Second, this study used data from a cross-sectional analysis; however, future research may potentially make use of a longitudinal design in order to more thoroughly confirm the findings.

Findings of this study offer substantial managerial insights suggesting various ways to develop better internal as well as external integration to get better results. Management of the company should focus and give more importance to job rotation, trainings and management commitment as part of internal integration. Moreover, management should strive for improving the capabilities of integration in internal functions prior to external integration as internal collaboration, teamwork and interaction within the company are considered as a precondition to maintain integration with external stakeholders. It is also a social process which needs to be built up over a longer period of time.

The authors contribute to the literature by experimentally evaluating the effects of integration practices on SC performance using a conceptual model drawn from current theories. The study also offer additional empirical evidence for Han et al. (2007), who found that SCI enhances firm performance through quality management in their analyses of the relationships between SCI, quality management practices and firm performance.

The purpose of this paper is to examine the effects of the government intervention and bank competition on small and medium enterprise (SME) external debt financing in Chinese capital market.

This study uses ordinary least squares with standard errors clustered at the firm level. In addition, the authors use the dynamic system generalized method of moments to address the possible endogeneity issue in the regressions.

Using a sample of 908 firms from 2000 to 2010, the authors found that SMEs are more likely to access bank loans only in regions with higher level of government intervention than median government intervention. Further, the result shows that the government is motivated to help SMEs to obtain more external debt in regions where the level of bank competition is lower than the median bank competition index. Last, the authors found evidence that firms with politically connected CEOs are likely to access bank loans.

This paper highlights that government intervention enables the SMEs to secure more bank loans. Second, the authors’ results imply that the government is motivated to help SMEs to obtain more external debt in regions with low level of bank competition.

This study contributes to the current literature by revealing that government intervention is the driving force alleviating SMEs’ constraints in accessing external financing. Second, this study finds the evidence to supports the argument that government has a strong motive to help SMEs to secure long-term credits for political purpose (Fan et al., 2012), when the level of bank competition is low (Berger and Udell, 2006).

This study aims to propose a semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the high-speed railway (HSR) subgrade under cyclic load.

According to the basic framework of critical state soil mechanics and in view of the characteristics of the coarse-grained soil filler for the HSR subgrade to bear the train vibration load repeatedly for a long time, the hyperbolic empirical relationship between particle breakage and plastic work was derived. Considering the influence of cyclic vibration time and stress ratio, the particle breakage correction function of coarse-grained soil filler for the HSR subgrade under cyclic load was proposed. According to the classical theory of plastic mechanics, the shearing dilatation equation of the coarse-grained soil filler for the HSR subgrade considering particle breakage was modified and obtained. A semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the HSR subgrade under cyclic load was further established. The backward Euler method was used to discretize the constitutive equation, build a numerical algorithm of “elastic prediction and plastic modification” and make a secondary development of the program to solve the cyclic compaction model.

Through the comparison with the result of laboratory triaxial test under the cyclic loading of coarse-grained soil filler for the HSR subgrade, the accuracy and applicability of the cyclic compaction model were verified. Results show that the model can accurately predict the cumulative deformation characteristics of coarse-grained soil filler for the HSR subgrade under the train vibration loading repeatedly for a long time. It considers the effects of particle breakage and stress ratio, which can be used to calculate and analyze the stress and deformation evolution law of the subgrade structure for HSR.

The research can provide a simple and practical method for calculating deformation of railway under cyclic loading.

This paper aims to first, examine teachers' conception of e‐learning and second, is to reveal how e‐learning is applied in teaching and learning in the field of Chinese higher education.

Various issues are reviewed in the instruction part, i.e. e‐learning applications in China, research and practices of e‐learning. The methodology applied in this study is phenomenography. Twenty‐four Chinese participants were interviewed in‐depth based on a protocol developed in the planning stage. The interviews are analysed from a grounded theory perspective and a set of conceptual categories are proposed.

Five categories, i.e. the centrality of the lecture, online cooperation learning, network learning, student learning, and infrastructure and access are identified in terms of the phenomenographic study. The findings demonstrate that the traditional teaching methods that dominate in China are unlikely to present conditions for mainstreaming e‐learning in the near future.

Traditional Chinese teaching culture still dominates in higher education, and teachers' conceptions do influence their teaching behaviours. Therefore, a training programme could be developed based on the categories of teachers' conceptions of e‐learning.

This study helps us to understand how Chinese teachers understand e‐learning and how they utilise e‐learning in their teaching and learning.

In the emerging economy, knowledge is now recognized as an important basis for competitive advantage and many firms are beginning to establish knowledge management systems (KMS). Within the last few years, although the topic of knowledge management (KM) has been studied, our understanding of how the design of the KMS affects its use and definition of KM is still rather limited. This paper presents a model of the enterprise’s knowledge trees, which is related to several knowledge management processes. The gray information and knowledge are, in their respective capacities, to provide the enterprise with great effectiveness. The gray dimension of enterprise knowledge is defined in line with the model of enterprise knowledge and fractal dimension. Also the key factors of KMS of shared knowledge are discussed in this paper. The results of the study will benefit not only the design of KMS, but also the business model transformation of competitive advantage.