Search results

The aerodynamic differences between the head car (HC) and tail car (TC) of a high-speed maglev train are significant, resulting in control difficulties and safety challenges in operation. The arch structure has a significant effect on the improvement of the aerodynamic lift of the HC and TC of the maglev train. Therefore, this study aims to investigate the effect of a streamlined arch structure on the aerodynamic performance of a 600 km/h maglev train.

Three typical streamlined arch structures for maglev trains are selected, i.e. single-arch, double-arch and triple-arch maglev trains. The vortex structure, pressure of train surface, boundary layer, slipstream and aerodynamic forces of the maglev trains with different arch structures are compared by adopting improved delayed detached eddy simulation numerical calculation method. The effects of the arch structures on the aerodynamic performance of the maglev train are analyzed.

The dynamic topological structure of the wake flow shows that a change in arch structure can reduce the vortex size in the wake region; the vortex size with double-arch and triple-arch maglev trains is reduced by 15.9% and 23%, respectively, compared with a single-arch maglev train. The peak slipstream decreases with an increase in arch structures; double-arch and triple-arch maglev trains reduce it by 8.89% and 16.67%, respectively, compared with a single-arch maglev train. The aerodynamic force indicates that arch structures improve the lift imbalance between the HC and TC of a maglev train; double-arch and triple-arch maglev trains improve it by 22.4% and 36.8%, respectively, compared to a single-arch maglev train.

This study compares the effects of a streamlined arch structure on a maglev train and its surrounding flow field. The results of the study provide data support for the design and safe operation of high-speed maglev trains.

The purpose of this paper in the editorial review of manuscripts to highlight the emergent aspects of original thinking that provide new perspectives on issues central to management.

A synoptic perspective of a very broad range of topics covered in research by scholars is provided: education, corporate value, quality, corporate social responsibility, risk behavior, managing reputation, expatriation, growth and creativity. In this particular review, the editor emphasizes those facets of the paper that shed original, new light on management. Also, the areas where research provides a theoretical basis for consulting or managerial practice are highlighted to illustrate how research can be of practical relevance.

Some of the insights gained clearly indicate the importance of research. For example, tighter or more rigorous governmental regulations on food quality are unlikely to contribute to the enhancement of firms’ capability in improving food quality. The government needs to do much more than only regulate. Then, there is empirical reaffirmation that guan-xi with government matters: better the relationships, the higher corporate value but only if the firm is in private hands, not for state-owned enterprises (SOEs). Then, the Chinese local firms’ nexus with foreign, and international corporations influences their corporate social performance. Even more fascinating, a bank’s risk behavior is dependent on the structural composition of the board of directors. Indeed, research shows that a gender mix in fact lowers the propensity toward taking a high risk. Then, through reflecting upon their deep researches, the authors derive a theoretic framework for coping with reputation loss following a financial restatement. Here, authors showed SOEs to suffer much more in the event of restatement than the privately owned enterprises. Then, in a piece of innovative research of expatriation, authors relate a spectrum of the Chinese cultural values to performance. In a cross-country (civilization) study, the research motivation is: Whether SMEs in China, India and Pakistan are confronting the same environmental challenges? As expected, the answer would be yes in some aspects and no in others. This a significant finding, as the Chinese are raised on a milieu of suppressing one’s emotions: emotional expressiveness can contribute to creativity!

In this paper, the editor highlights some aspects on the original thinking of the authors within this issue of Chinese Management Studies. Also, the editor highlights on how research contained herein is contributing to managerial (consulting) practice.

The goal of this research is to develop a dynamic step path planning algorithm based on the rapidly exploring random tree (RRT) algorithm that combines Q-learning with the Gaussian distribution of obstacles. A route for autonomous vehicles may be swiftly created using this algorithm.

The path planning issue is divided into three key steps by the authors. First, the tree expansion is sped up by the dynamic step size using a combination of Q-learning and the Gaussian distribution of obstacles. The invalid nodes are then removed from the initially created pathways using bidirectional pruning. B-splines are then employed to smooth the predicted pathways.

The algorithm is validated using simulations on straight and curved highways, respectively. The results show that the approach can provide a smooth, safe route that complies with vehicle motion laws.

An improved RRT algorithm based on Q-learning and obstacle Gaussian distribution (QGD-RRT) is proposed for the path planning of self-driving vehicles. Unlike previous methods, the authors use Q-learning to steer the tree's development direction. After that, the step size is dynamically altered following the density of the obstacle distribution to produce the initial path rapidly and cut down on planning time even further. In the aim to provide a smooth and secure path that complies with the vehicle kinematic and dynamical restrictions, the path is lastly optimized using an enhanced bidirectional pruning technique.