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This method will become a new development trend in subgrade structure design for high speed railways.

This paper summarizes the structural types and design methods of subgrade bed for high speed railways in China, Japan, France, Germany, the United States and other countries based on the study and analysis of existing literature and combined with the research results and practices of high speed railway subgrade engineering at home and abroad.

It is found that in foreign countries, the layered reinforced structure is generally adopted for the subgrade bed of high speed railways, and the unified double-layer or multi-layer structure is adopted for the surface layer of subgrade bed, while the simple structure is adopted in China; in foreign countries, different inspection parameters are adopted to evaluate the compaction state of fillers according to their respective understanding and practice, while in China, compaction coefficient, subsoil coefficient and dynamic deformation modulus are adopted for such evaluation; in foreign countries, the subgrade top deformation control method, the subgrade bottom deformation control method, the subsurface fill strength control method are mainly adopted in subgrade bed structure design of high speed railways, while in China, dynamic deformation control of subgrade surface and dynamic strain control of subgrade bed bottom layer is adopted in the design. However, the cumulative deformation of subgrade caused by train cyclic vibration load is not considered in the existing design methods.

This paper introduces a new subgrade structure design method based on whole-process dynamics analysis that meets subgrade functional requirements and is established on the basis of the existing research at home and abroad on prediction methods for cumulative deformation of subgrade soil.

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.

The misalignment is generally inevitable in the process of machining and assembly of rotor systems with gas foil bearings, but the exploration on this phenomenon is relatively less. Therefore, the purpose of this paper is to carry out the thermo-elastohydrodynamic analysis of the foil bearing with misalignment, especially the inhomogeneous foil bearing.

The rotor is allowed to misalign in two non-rotating directions. Then the static and dynamic performance of the inhomogeneous foil bearing is studied. The thermal-elastohydrodynamic analysis is realized by combining the Reynolds equation, foil deformation equation and energy equation. The small perturbation method is used to calculate the dynamic coefficients, then the critical whirl ratio is obtained.

The gas pressure, film thickness and temperature distribution distort when the misalignment appears. The rotor misalignment can improve the loading capacity but rise the gas temperature at the same time. Furthermore, the rotor misalignment can affect the critical whirl ratio which demonstrates that it is necessary to analyze the misalignment before the rotordynamic design.

The value of this paper is the exploration of the thermo-elastohydrodynamic performance of the inhomogeneous foil bearing with misalignment, the analysis procedure and the corresponding results are valuable for the design of turbo system with gas foil bearings.

This paper aims to identify and systematically analyze the causal-effect relationships among barriers to circular food supply chains in China.

Grounded in multiple organizational theories, this paper develops a theoretical framework for identifying relevant barriers to integrating circular economy philosophy in food supply chain management. The study uses 105 responses from Chinese food supply chain stakeholders including food processors, sales and distribution channels, consumers and government officials. It applies a fuzzy decision-making trial and evaluation laboratory (DEMATEL) method to examine the causal-effect relationships among the identified barriers.

Overall, the results suggest two key cause barriers: first, weak environmental regulations and enforcement, and second, lack of market preference/pressure. Meanwhile, lack of collaboration/support from supply chain actors is the most prominent barrier. The key cause and prominent barriers are also identified for each of the supply chain stakeholder involved.

The study offers practical insights for overcoming barriers to integrating circular economy philosophy in the management of supply chains in the Chinese food sector, as well as in other contexts where similar challenges are faced. It also sheds light on which organizational theories are most suitable for guiding similar studies.

To the best of the authors’ knowledge, this is the first barrier study on circular food supply chains. The use of multiple organizational theories for the development of the theoretical framework is unique in barrier studies. The study offers insights from multiple stakeholders in the Chinese food supply chains.

This study examines the antecedents and dynamics of authoritarian leadership and extends the effects of managers' sleep quality to employee behavior.

On the basis of self-regulation theory, 513 unit day samples were analyzed using cross-level path analysis and a Monte Carlo simulation test.

Managers' sleep quality is positively related to authoritarian leadership and positive emotions play a mediating role. Authoritarian leadership is positively related to employees' counterproductive behavior. Managers' sleep quality affects employees' counterproductive behavior through managers' positive emotions and authoritarian leadership.

Individuals should learn to reduce stress and maintain a positive mood. Organizations should reduce employees' overtime work and work stress and find other ways to improve employees' sleep quality.

First, we considered authoritarian leadership to be dynamic and studied it on a daily basis. Second, we studied the antecedents of authoritarian leadership from the perspective of leaders' states (sleep quality and emotions). Third, we discussed the effect of managers' sleep quality on employee behavior.

Small and medium enterprises (SMEs) are expected to be more creative and innovative to survive in the business competition and to make their businesses environmentally friendly, to develop global supply chain strategies, and to make innovations in products and business processes to become indispensable. This study discusses the effect of green supply chain integration (GSCI) and environmental uncertainty on performance through the moderation of green innovation. Structural equation modeling and maximum likelihood estimation were used to analyze a sample of 130 SMEs in East Java, Indonesia. The result shows that GSCI and environmental uncertainty significantly affect performance, and green innovation significantly moderates the effect. This research found that SME’s performance is influenced by GSCI concept and green innovation application as well as SME’s understanding about recent and future environmental uncertainties; this fits the market demand.

In past decades, artificial neural network (ANN) models have revolutionised various stock market operations due to their superior ability to deal with nonlinear data and garnered considerable attention from researchers worldwide. The present study aims to synthesize the research field concerning ANN applications in the stock market to a) systematically map the research trends, key contributors, scientific collaborations, and knowledge structure, and b) uncover the challenges and future research areas in the field.

To provide a comprehensive appraisal of the extant literature, the study adopted the mixed approach of quantitative (bibliometric analysis) and qualitative (intensive review of influential articles) assessment to analyse 1,483 articles published in the Scopus and Web of Science indexed journals during 1992–2022. The bibliographic data was processed and analysed using VOSviewer and R software.

The results revealed the proliferation of articles since 2018, with China as the dominant country, Wang J as the most prolific author, “Expert Systems with Applications” as the leading journal, “computer science” as the dominant subject area, and “stock price forecasting” as the predominantly explored research theme in the field. Furthermore, “portfolio optimization”, “sentiment analysis”, “algorithmic trading”, and “crisis prediction” are found as recently emerged research areas.

To the best of the authors’ knowledge, the current study is a novel attempt that holistically assesses the existing literature on ANN applications throughout the entire domain of stock market. The main contribution of the current study lies in discussing the challenges along with the viable methodological solutions and providing application area-wise knowledge gaps for future studies.

The purpose of this paper is to apply He's variational iteration method (VIM) coupled with an auxiliary parameter, which proves very effective to control the convergence region of approximate solution.

The proposed algorithm is tested on generalized Hirota‐Satsuma coupled KdV equation.

Numerical results explicitly reveal the complete reliability, efficiency and accuracy of the suggested technique.

It is observed that the approach may be implemented on other nonlinear models of physical nature.

Green entrepreneurship is gaining more attention as the interest in sustainability is growing. This is mainly because consumer awareness is rising and thus many regulations have been implied and several research are proving positive relationship from the use of green entrepreneurship. Using enterprise data for the Republic of Albania (ALB), this study examines the effects of green entrepreneurship on firm performance. Our findings when we investigate the determinants of firm performance, the green entrepreneurship, certification, innovation activities, foreign ownership, and monitoring energy appear to have a positive impact on firm performance, while the effect of direct export is negative.

The purpose of this paper is to review and integrate cross-disciplinary research on the role of information technology (IT) on innovation published in the past 10 years.

The study follows the recommendations for systematic integrative literature review. The authors focus on the manuscripts published in the period between 2009 and 2018 in the top 8 Information Systems journals. Further, the authors specifically focus on the studies conducted at the individual and/or group level of analysis.

First, the authors find that there has been relatively little research published focusing on the role of IT in innovation at the individual and/or group level of analysis. Among the published studies the authors find equivocal insights on the role of IT in innovation. While IT can support innovation, it can also cause technostress and become an impeding element by institutionalizing established organizational practices.

Despite the importance of the topic, there has been little research on the role of IT in supporting innovation published in the small-and medium-size enterprise development journals. Through cross-disciplinary integration, the authors’ provide a foundation for future research on the topic.