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This chapter reviews the competition between full-service carrier (FSC) and low-cost carrier (LCC) in China. More importantly, we discuss the impacts of the COVID-19 pandemic on FSC–LCC competition. Specifically, the airlines' route choices and also the market contact between FSCs and LCCs in China are examined and discussed. Our review results suggest that, despite the rapid growth of the independent LCC Spring Airlines and the establishment of new subsidiary LCCs by FSCs, China's LCC sector still plays relatively minor roles compared with many fully deregulated markets. Subsidiary LCCs serve more as competitive tools for their parent FSCs, primarily deployed on their parent FSCs' routes to jointly compete against rival FSCs. This competition is primarily focused on niche regional markets rather than engaging in full-scale competition. Spring Airlines also strategically avoided direct head-to-head competition with FSCs before the pandemic by mainly connecting with the secondary cities. However, the pandemic has introduced significant changes, notably the network differentiation between FSCs and LCCs in mainland China. With the relaxation of government's regulations on airline route entries into hub airports during pandemic, Chinese LCCs have shifted their focus toward serving more dense routes, especially those connected to the top five cities. This shift has led to an intensified head-to-head competition between LCCs and FSCs following the outbreak of the pandemic. Such a process is likely to continue in the years to come. This chapter's discussions could also provide new insights into LCC development and the impact of the pandemic on FSC–LCC competition interactions to supplement existing literature studying other major airline markets.

This chapter reviews the effects of air transport liberalization, and investigates the roles played by airport-airline vertical arrangements in liberalizing markets. Our investigation concludes that liberalization has led to substantial economic and traffic growth. Such positive outcomes are mainly due to increased competition and efficiency gains in the airline industry, and positive externalities to the overall economy. Liberalization allows airlines to optimize their networks, and thus may introduce substantial demand and financial uncertainty to airports. Vertical arrangements between airlines and airports may offer a wide range of benefits to the parties involved, yet such arrangements could also lead to airline entry barriers which reduce the effects of liberalization. Three approaches have been developed to model the effects of liberalization in complex market conditions, which include the analytical, econometric and computational network methods. These approaches should be selectively utilized in policy studies on liberalization.

This chapter reviews the key results obtained in previous studies of airline mergers. It is found that the effect of mergers on airfares is dependent on the network configurations of merging airlines. Fare increases are frequently observed on overlapped routes. However, if the networks of two merging airlines are complementary, the expanded network after the merger leads to cost savings, increase in travel options, and improvement in service quality. Therefore, in a deregulated market, with few entry barriers, relaxing merger regulations is likely to improve welfare. However, most welfare evaluations do not incorporate quality changes or dynamic competition effects. Empirical investigations are primarily ex post analysis of mergers that have already passed antitrust reviews. The relationship between market concentration and welfare might be nonlinear and market specific. Therefore, airline mergers and alliances should be reviewed case by case. Methodological improvements are needed in future studies to control for the effects of complicating factors inherent in ex post evaluations.

The purpose of this paper is to study the realization of turn‐over‐wok movement for a cooking robot.

First, the authors introduce the cooking robot's movement mechanism and its realization methods and then analyze the movement geometric of the movement mechanism. The authors conduct the force analysis of the material in the wok motion and suppose the moving situation of mass point m when turning over the wok and shaking the wok.

The problem of the cooking robot simulating the special cooking motion made by a chef is solved.

The robot is applicable to being a cooking robot for Chinese dishes.

The paper shows how to optimize the effect of material moving track and satisfies the requirements of wok motion of cooking robot.

This paper is supposed to provide a critical review of current research progress on thermal management in grinding of superalloys, and future directions and challenges. By understanding the current progress and identifying the developing directions, thermal management can be achieved in the grinding of superalloys to significantly improve the grinding quality and efficiency.

The relevant literature is collected from Web of Science, Scopus, CNKI, Google scholar, etc. A total of 185 literature is analyzed, and the findings in the literature are systematically summarized. In this case, the current development and future trends of thermal management in grinding of superalloys can be concluded.

The recent developments in grinding superalloys, demands, challenges and solutions are analyzed. The theoretical basis of thermal management in grinding, the grinding heat partition analysis, is also summarized. The novel methods and technologies for thermal management are developed and reviewed, i.e. new grinding technologies and parameter optimization, super abrasive grinding wheel technologies, improved lubrication, highly efficient coolant delivery and enhanced heat transfer by passive thermal devices. Finally, the future trends and challenges are identified.

Superalloys have excellent physical and mechanical properties, e.g. high thermal stability, and good high-temperature strength. The superalloys have been broadly applied in the aerospace, energy and automobile industries. Grinding is one of the most important precision machining technologies for superalloy parts. Owing to the mechanical and physical properties of superalloys, during grinding processes, forces are large and a massive heat is generated. Consequently, the improvement of grinding quality and efficiency is limited. It is important to conduct thermal management in the grinding of superalloys to decrease grinding forces and heat generation. The grinding heat is also dissipated in time by enhanced heat transfer methods. Therefore, it is necessary and valuable to holistically review the current situation of thermal management in grinding of superalloys and also provide the development trends and challenges.

The aim of this paper is to provide a new wafer prealigning robot for the photo‐etching facility during the manufacturing of IC products.

The shape center is measured by a reflection‐style laser sensor in the wafer's radial direction, and the position is measured by a penetration‐style laser sensor. A dynamic error compensation is applied to eliminate the radial runout and wobble of the rotary stage, which have effects on the measurement of the wafer's shape center.

It is found that the new wafer prealigning robot can satisfy the accuracy requirement.

The robot requires that the shape center can be accurately calculated.

The robot is applicable to wafer prealigning for the photo‐etching facility.

A wafer prealigning robot based on the shape center calculation method has been developed and is described in the paper.

The proposed DHHFLOWLAD is used to design a recommendation system, which aims to provide the most appropriate treatment to the patient under a double hierarchy hesitant fuzzy linguistic environment.

Based on the ordered weighted distance measure and logarithmic aggregation, we first propose a double hierarchy hesitant fuzzy linguistic ordered weighted logarithmic averaging distance (DHHFLOWLAD) measure in this paper.

A case study is presented to illustrate the practicability and efficiency of the proposed approach. The results show that the recommendation system can prioritize TCM treatment plans effectively. Moreover, it can cope with pattern recognition problems efficiently under uncertain information environments.

An expert system is proposed to combat COVID-19 that is an emerging infectious disease causing disruptions globally. Traditional Chinese medicine (TCM) has been proved to relieve symptoms, improve the cure rate, and reduce the death rate in clinical cases of COVID-19.

The purpose of this paper is to present a serial produced industrial robot for thin‐type space solar cells (SSC), which is applied to perform the bonding process of SSC.

An optimized process of adhesive coating and bonding for SSC is designed, based on an analysis of hydromechanics model. In order to perform the process, a novel robot is developed, which mainly consists of a three‐axis Cartesian coordinates' motion platform, coating‐and‐bonding device, solar cell and glass cover orientation plate, control system, pneumatic system, constant temperature module, and industrial personal computer software. The coating and bonding operation is based on the three‐axis Cartesian coordinates' motion and the help of pneumatic system.

Compared with the experimental prototype and handwork, the robot is more effective and reliable for the bonding process of the thin‐type solar cells.

The robot is very useful to realize automatic production of SSC.

This paper aims to present a robust design approach to realize disturbance attenuation for a yaw – pitch gimballed system subject to actuator saturation and disturbances.

To minimize the impacts of disturbances in the presence of saturation nonlinearity and acquire desired response performance, the control approach is of double closed-loop configuration. State feedback controllers are synthesized via convex optimization and used to stabilize the inner loops; robust controllers are synthesized via mixed H _∞ optimization and used to stabilize the outer loops.

It is shown through performance simulations that the proposed control scheme is effective in terms of command following, stability and disturbance attenuation.

The presented robust control approach provides a theoretical method to facilitate designing a stable servo control loop for a yaw – pitch gimballed seeker.

This paper supplies an effective way of addressing stabilization problem induced from actuator saturation and system uncertainties.