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The characteristics of spherical robots, such as under-drive, non-holonomic constraints and strong coupling, make it difficult to establish its motion control model accurately. To improve the anti-interference performance of spherical robots in practical engineering, this paper proposes a spherical robot motion controller based on auto-disturbance rejection control (ADRC) with parameter tuning.

This paper considers the influences of the spherical shell, internal frame and pendulum on the movement of the spherical robot during the rotation to establish the multi-body dynamics model of the XK-I spherical robot. Due to the serious coupling problem of the dynamic model, the motion control state equation is constructed using linearization and decoupling. The XK-I spherical robot PSO-ADRC motion controller with parameter tuning function is designed by combining the state equation with the particle swarm optimization (PSO) algorithm. Finally, experiments are performed to evaluate the feasibility of PSO-ADRC in an actual case compared to ADRC, PSO-PID and PID.

By analyzing the required time to reach the expected value, the control stability and the fluctuation range of the standard deviation after reaching the expected value, the superiority of PSO-ADRC to ADRC, PSO-PID and PID is demonstrated in terms of the speed and anti-interference ability.

The proposed method can be applied to the robot control field.

A parameter-tuning method for auto-disturbance-rejection motion control of the spherical robot is proposed. According to the experimental results, the anti-interference ability of the spherical robot moving on uneven ground is improved. Therefore, it provides a foundation for the autonomous environmental monitoring of the spherical robot equipped with sensors.

In complex environments, a spherical robot has great application value. When the pendulum spherical robot is stopped or disturbed, there will be a periodic oscillation. This situation will seriously affect the stability of the spherical robot. Therefore, this paper aims to propose a control method based on backstepping and disturbance observers for oscillation suppression.

This paper analyzes the mechanism of oscillation. The oscillation model of the spherical robot is constructed and the relationship between the oscillation and the internal structure of the sphere is analyzed. Based on the oscillation model, the authors design the oscillation suppression control of the spherical robot using the backstepping method. At the same time, a disturbance observer is added to suppress the disturbance.

It is found that the control system based on backstepping and disturbance observer is simple and efficient for nonlinear models. Compared with the PID controller commonly used in engineering, this control method has a better control effect.

The proposed method can provide a reliable and effective stability scheme for spherical robots. The problem of instability in real motion is solved.

In this paper, the oscillation model of a spherical robot is innovatively constructed. Second, a new backstepping control method combined with a disturbance observer for the spherical robot is proposed to suppress the oscillation.

This study aims to present an automated guided logistics robot mainly designed for pallet transportation. Logistics robot is compactly designed. It could pick up the pallet precisely and transport the pallet up to 1,000 kg automatically in the warehouse. It could move freely in all directions without turning the chassis. It could work without any additional infrastructure based on laser navigation system proposed in this work.

Logistics robot should be able to move underneath and lift up the pallet accurately. Logistics robot mainly consists of two sub-robots, like two forks of the forklift. Each sub-robot has front and rear driving units. A new compact driving unit is compactly designed as a key component to ensure access to the narrow free entry of the pallet. Besides synchronous motions in all directions, the two sub-robots should also perform synchronous lifting up and laying down the pallet. Logistics robot uses a front laser to detect obstacles and locate itself using on-board navigation system. A rear laser is used to recognize and guide the sub-robots to pick up the pallet precisely within ± 5mm/1o in x-/yaw direction. Path planning algorithm under different constraints is proposed for logistics robot to obey the traffic rules of pallet logistics.

Compared with the traditional forklift vehicles, logistics robot has the advantages of more compact structure and higher expandability. It can realize the omnidirectional movement flexibly without turning the chassis and take zero-radius turn by controlling compact driving units synchronously. Logistics robot can move collision-free into any pallet that has not been precisely placed. It can plan the paths for returning to charge station and charge automatically. So it can work uninterruptedly for 7 × 24 h. Path planning algorithm proposed can avoid traffic congestion and improve the passability of the narrow roads to improve logistics efficiencies. Logistics robot is quite suitable for the standardized logistics factory with small working space.

This is a new innovation for pallet transportation vehicle to improve logistics automation.

The e-learning-based approach is critical in keeping the wheels of education turning in the face of the COVID-19 epidemic. In this scenario, analyzing the implementation of the e-learning system is required to properly grasp the needs. The purpose of this paper is to demonstrate the relationship between technical system quality, information quality, service quality, educational system quality, support system quality, learner quality, instructor quality, perceived satisfaction, perceived usefulness, e-learning system use and benefits.

This study was carried out by giving online questionnaires to students attending private institutions in Indonesia. A total of 593 students participated in the study and provided responses. The structural equation model, which is supported by the program WarpPLS7.0, is used to analyze the data.

Maintaining the quality of the technological system, the information system, the learners and the educational system can help achieve the goal of increasing perceived utility. In the meanwhile, factors such as inadequate service quality, educational system quality, support system quality and teacher quality can all pose challenges to perceived levels of satisfaction. To get the most out of e-learning apps, users' expectations about how fun, useful and easy to use they are need to be met.

This study was carried out in the midst of the COVID-19 epidemic with a restricted number of participants from Indonesian institutions of higher education. This research has the potential to be expanded into a variety of different types of higher education in the future.

The main thing that will determine whether an e-learning system model works is the quality of the learners.

The institution should think about changing the material offered in the e-learning system to make it easier for students to grasp by describing the current material and providing digital handouts of lecturers' explanations. This study expanded the e-learning system success model and applied it to the evaluation of e-learning deployment in Indonesian higher education. This study will improve student comprehension of the e-learning model and contribute to the body of knowledge about e-learning applications and technology.

This study traces the boundaries of online-based social networks and its possible extensions and intersections with offline social networks. It focuses on the massive multiplayer online (MMO) gaming community. Most online gaming research has only addressed one side of the equation, that is, the online aspect of social interaction, omitting the offline context. The primary objective is to look at both offline and online social contexts of gamers. The data analyzed here are part of a bigger research project. Using a sample of 242 respondents and a total of 1,452 social ties (three online and three offline) this work addresses the differences and similarities between online gamer’s offline and online networks. Around 72% of the participants were between the ages of 18 and 37. This group provides insight into the management of social interactions and ties in the digital age among millennials and the coming-of-age of Generation Z. The analysis suggests that overall offline ties are slightly more important than online. Still, this does not imply that online ties are not meaningful at all. The length of their online relationships plays a significant role in how participants qualify their ties. Most participants that had not met face-to-face were willing to meet their online ties. They also reported sharing personal and everyday life matters with their online social network at a lower rate of their offline network. Time spent with online relationships stemming from online gaming and a cooperative environment is more likely to be considered higher quality time. This suggests that in MMOs the gap between online and offline relationships is becoming narrower.

In a past era, alchemists believed they could magically transmute lead into valuable gold. Science has progressed a substantial distance since then and for decades nuclear and particle physicists could change various materials into gold. When considering technology, leaders are faced with a comparable challenge: How does one leverage technology to create unique organizational value? To manage emerging technologies effectively to create organizational value, managers will need to lead the producers and practitioners of technology effectively. In the age of global interdependence, organizations must abandon old outdated perspectives.

Technology is a force which drives itself. Organizations must adopt to emerging technology or risk being obsolete. Leveraging technology to create value involves more then circumferentially managing technology. To create value, leaders must encourage staff to transmute technology. The principles and practices of quantum leadership provide for this possibility. This chapter will irradiate why simply managing technology does not offer organizations the maximum value from technology. The reader will be introduced to the four core features of quantum leadership: duality, superposition, entanglement, and observation. With this groundwork, the principles and practices of this leadership perspective will be discussed in context of transmuting technology into unique organizational value. Which lens one uses to see which possibility becomes reality are exclusively in the eyes of the viewer. Using information systems technology, artificial intelligence (AI), and 5G technology as the exemplars, readers can decide whether to accept, reject, or suspend judgement on using quantum leadership as the perspective to transmute technology into valuable organizational gold.

This paper aims to study the affecting factors on bird nesting on electronic railway catenary lines and the impact of bird nesting events on railway operation.

First, with one year’s bird nest events in the form of unstructured natural language collected from Shanghai Railway Bureau, the records were structured with the help of python software tool. Second, the method of root cause analysis (RCA) was used to identify all the possible influencing factors which are inclined to affect the probability of bird nesting. Third, the possible factors then were classified into two categories to meet subsequent analysis separately, category one was outside factors (i.e. geographic conditions related factors), the other was inside factors (i.e. railway related factors).

It was observed that factors of city population, geographic position affect nesting observably. Then it was demonstrated that both location and nesting on equipment part have no correlation with delay, while railway type had a significant but low correlation with delay.

This paper discloses the principle of impacts of nest events on railway operation.

This study relied on the job demands and resource model to understand employees’ turnover intentions. Recent studies have consistently lent support for the significant association between role ambiguity and turnover intentions; however, only a handful of studies focused on examining the potential mediators in this association. The authors argued that role ambiguity positively influences turnover intentions through affective mechanisms: job involvement and satisfaction.

To test the model, a large sample of working adults participated (N = 505).

Structural equation modeling results showed that role ambiguity, job involvement and job satisfaction were significantly associated with turnover intentions. Moreover, a serial mediation was found among the variables: employees with low levels of role ambiguity tended to report higher job involvement, which further increased their satisfaction with the job and subsequently decreased their turnover intentions.

The cross-sectional design is a limitation.

Practical suggestions regarding how organizations can reduce employee turnover are discussed.

The findings provide support for theory-driven interventions to address developing the intention to stay at work among working adults.

This chapter examines China’s corporate governance and accounting environment that shapes the adoption of internationally acceptable principles and standards. Specifically, it examines international influences, including supranational organizations; foreign investors and international accounting firms; domestic institutional influences, including the political system, economic system, legal system, and cultural system; and accounting infrastructure. China’s convergence is driven by desired efficiency of the corporate sector and legitimacy of participating in the global market. Influenced heavily by international forces in the context of globalization, corporate governance and accounting practices are increasingly becoming in line with internationally acceptable standards and codes. While convergence assists China in obtaining legitimacy, improving efficiency is likely to be adversely affected given that corporate governance and accounting in China operate in an environment that differs considerably from those of Anglo-American countries. An examination of the corporate governance and accounting environment in China suggests heavy government involvement within underdeveloped institutions. While the Chinese government has made impressive progress in developing the corporate governance and accounting environment for the market economy, China’s unique institutional setting is likely to affect how the imported concepts are interpreted and implemented.