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The purpose of this paper is to explore two dimensions of leadership practices (i.e. teaching and learning and sources of power) used by two exemplary principals in mainland China against a background of education reform and to identify how broader contextual factors have shaped these two dimensions of their leadership.

An exploratory case study was used that drew upon semi‐structured interviews, observations and document analysis. Interviews were conducted with two principals, six teachers from each of the two schools and a superintendent who was the supervisor of the two principals.

The findings reveal that there are some common elements in both of the leaders' practices but also some subtle differences. Both leaders emphasise teaching and learning. One sees herself as curriculum expert; the other delegate teaching responsibilities. While both uses a top down approach, one principal uses an adversarial approach and the other a more facilitative approach.

The study used a small sample size. It explored the leaders' practices in the light of broader contextual factors rather than personal factors or gender‐based factors

Given the limited empirical research conducted on female principals in mainland China, this qualitative study provides insights into two dimensions of leadership used by two exemplary principals and explains their practices in the light of critical contextual factors such as contemporary and traditional Chinese culture and the school's organisational context.

This study aims to characterize the mechanical properties of sintered nano-silver under various sintering processes by nano-indentation tests.

Through microstructure observations and characterization, the influences of sintering process on the microstructure evolutions of sintered nano-silver were presented. And, the indentation load, indentation displacement curves of sintered silver under various sintering processes were measured by using nano-indentation test. Based on the nano-indentation test, a reverse analysis of the finite element calculation was used to determine the yielding stress and hardening exponent.

The porosity decreases with the increase of the sintering temperature, while the average particle size of sintered nano-silver increases with the increase of sintering temperature and sintering time. In addition, the porosity reduced from 34.88%, 30.52%, to 25.04% if the ramp rate was decreased from 25°C/min, 15°C/min, to 5°C/min, respectively. The particle size appears more frequently within 1 µm and 2 µm under the lower ramp rate. With reverse analysis, the strain hardening exponent gradually heightened with the increase of temperature, while the yielding stress value decreased significantly with the increase of temperature. When the sintering time increased, the strain hardening exponent increased slightly.

The mechanical properties of sintered nano-silver under different sintering processes are clearly understood.

This paper could provide a novel perspective on understanding the sintering process effects on the mechanical properties of sintered nano-silver.

Research about the modern mutually beneficial nonprofit organizations (MBNPOs) has great value because of the increasingly important role that the MBNPO plays in society. The establishment and management of MBNPOs are critical for its development.

Integrated marketing communications (IMC) theory is applied to the research on establishment and management innovation. The establishment of MBNPOs needs four sequential steps: identifying the target group, providing services to meet the demand of stakeholders, designing appropriate communication tactics and deploying proper organizational structure to accomplish efficient communication.

Three types of approach enable traditional enterprises to transform into MBNPOs: product innovation, operational innovation and synergetic development. The application of IMC theory accomplishes management innovation of MBNPOs in three aspects: leading market-orientation specific to stakeholder-orientation, making management innovation systematic in MBNPOs and clarifying targets of management innovation in MBNPOs.

This is one of the first examinations of establishment path and management innovation of MBNPO based on IMC theory.

Through a lot of investigation, many times of demonstrating scheme, the in-depth theoretic analysis, a large scale numeric simulation tests and the field tests, the operating line of the rapid excavation is equipped which are consisting of the way of the drilling and blasting, the bolt-mesh-spurting supporting and the trackless transportation. The key technology which includes the stable technology of controling the surrounding rock, the optimization technology of transportation system, the excavating technology of layered drilling and the technology of parallel and cross operation develops the integral management framework and the advanced technology framework with the operating line, which realizes the safe and efficient construction and provides rich experience for the similar mines.

The purpose of this extended editorial is to elaborate on the possible future trajectories of critical perspectives on international business. In addition, the content of the current issue is introduced.

This editorial reviews recent reflections on the field of international business to identify the concerns of mainstream scholars and to contrast these with those of central concern to critical scholars of international business. In the light of this, consideration is given to how critical perspectives on international business seeks to facilitate the development of academic debates that continue to question orthodox approaches to international business whilst also offering relevance for all stakeholders in international business activities from managers, shareholders and policy makers to workers, consumers and citizens, including future generations.

Taking stock of recent reflections on the future of the field of international business is useful in determining possible topics for future contributions to critical perspectives on international business.

This is the first attempt to review reflections on the future of international business since the Global Financial crisis of 2008. As such it offers an assessment of the current thinking in the field and offers directions for the development of critical perspectives on international business.

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.

This research aims to present a novel cooperative control architecture designed specifically for roads with variations in height and curvature. The primary objective is to enhance the longitudinal and lateral tracking accuracy of the vehicle.

In addressing the challenges posed by time-varying road information and vehicle dynamics parameters, a combination of model predictive control (MPC) and active disturbance rejection control (ADRC) is employed in this study. A coupled controller based on the authors’ model was developed by utilizing the capabilities of MPC and ADRC. Emphasis is placed on the ramifications of road undulations and changes in curvature concerning control effectiveness. Recognizing these factors as disturbances, measures are taken to offset their influences within the system. Load transfer due to variations in road parameters has been considered and integrated into the design of the authors’ synergistic architecture.

The framework's efficacy is validated through hardware-in-the-loop simulation. Experimental results show that the integrated controller is more robust than conventional MPC and PID controllers. Consequently, the integrated controller improves the vehicle's driving stability and safety.

The proposed coupled control strategy notably enhances vehicle stability and reduces slip concerns. A tailored model is introduced integrating a control strategy based on MPC and ADRC which takes into account vertical and longitudinal force variations and allowing it to effectively cope with complex scenarios and multifaceted constraints problems.

This paper aims to develop an additive manufacturing technique for complex zirconia ceramic dental bridges.

To carry out this study, a dental bridge model was obtained by three-dimensional reverse engineering, and a light-curable zirconia ceramic suspension was formulated. Zirconia bridges were manufactured by stereolithography and then treated by vacuum freeze drying, vacuum infiltration and sintering. The optimal scanning speed was determined according to the shape precision comparison. Then, characteristics of the sintered ceramic parts were tested as size shrinkage, relative density, surface Vickers hardness, surface roughness and microstructure.

The method for preparation of light-curable zirconia suspension (40 volume per cent solid loading) with a viscosity value of 127 mPa·s was proposed. The optimal laser scanning speed for zirconia bridge fabrication was 1200 mm/s. A relative density of 98.58 per cent was achieved; the obtained surface Vickers hardness and surface roughness were 1,398 HV and 2.06 µm, respectively.

This paper provides a potential technical method for manufacturing complex zirconia dental bridges and other small complex-shaped ceramic components which are difficult to be made by other manufacturing techniques.