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The outbreak of the COVID-19 pandemic brought about rapid changes in higher education (HE) pedagogies, with universities adding online options to their core face to face offering. The use of technology to facilitate learning has been a mainstay in traditional distance education settings. The paper aims to understand student and teacher experience of synchronous online learning in HE to develop practice and assist those newly coming to online teaching.

The authors conducted a ‘rapid review’ of articles related to this topic over the last 21 years. Thematic analysis of the 61 studies identified for inclusion were; Use of technology, planned pedagogy, comparison of synchronous and asynchronous learning, relationships online, teacher and student attitudes, COVID-19 reflections.

This study’s findings show many studies examined the transition from classroom to online learning, rather than the experience of being online. Building a community of learning, with interaction between all parties, was central to success in the development of an approach to online synchronous teaching.

Few of the early papers included here expressly explored student and teacher experiences of synchronous learning. Instead, they broadly discussed blended learning, or compared functionality and effectiveness of online teaching, with traditional in person or offline/asynchronous alternatives. An additional drawback was that educators were frequently involved in studies which investigated the experiences of their own students.

This study is one of the few to focus on the experience of staff and students in the online synchronous environment. The results show there is scope to achieve improvement in online learning, through research focussed on how students, lecturers and institutional administrators adapt to the new normal.

Permanent magnet synchronous spherical motors can have wide use in robotics and industrial automation. They enable three-DOF omnidirectional motion of their rotor. They are suitable for several applications, such as actuation in robotics, traction in electric vehicles and use in several automation systems. Unlike conventional synchronous motors, permanent magnet synchronous spherical motors consist of a fixed inner shell, which is the stator, and a rotating outer shell, which is the rotor. Their dynamic model is multivariable and strongly nonlinear. The treatment of the associated control problem is important.

In this paper, the multivariable dynamic model of permanent magnet synchronous spherical motors is analysed, and a nonlinear optimal (H-infinity) control method is developed for it. Differential flatness properties are proven for the spherical motors’ state-space model. Next, the motors’ state-space description undergoes approximate linearization with the use of first-order Taylor series expansion and through the computation of the associated Jacobian matrices. The linearization process takes place at each sampling instance around a time-varying operating point, which is defined by the present value of the motors’ state vector and by the last sampled value of the control input vector. For the approximately linearized model of the permanent magnet synchronous spherical motors, a stabilizing H-infinity feedback controller is designed. To compute the controller’s gains, an algebraic Riccati equation has to be repetitively solved at each time-step of the control algorithm. The global stability properties of the control scheme are proven through Lyapunov analysis. Finally, the performance of the nonlinear optimal control method is compared against a flatness-based control approach implemented in successive loops.

Due to the nonlinear and multivariable structure of the state-space model of spherical motors, the solution of the associated nonlinear control problem is a nontrivial task. In this paper, a novel nonlinear optimal (H-infinity) control approach is proposed for the dynamic model of permanent magnet synchronous spherical motors. The method is based on approximate linearization of the motor’s state-space model with the use of first-order Taylor series expansion and the computation of the associated Jacobian matrices. Furthermore, the paper has introduced a different solution to the nonlinear control problem of the permanent magnet synchronous spherical motor, which is based on flatness-based control implemented in successive loops.

The presented control approaches do not exhibit any limitations, but on the contrary, they have specific advantages. In comparison to global linearization-based control schemes (such as Lie-algebra-based control), they do not make use of complicated changes of state variables (diffeomorphisms) and transformations of the system's state-space description. The computed control inputs are applied directly to the initial nonlinear state-space model of the permanent magnet spherical motor without the intervention of inverse transformations and thus without coming against the risk of singularities.

The motion control problem of spherical motors is nontrivial because of the complicated nonlinear and multivariable dynamics of these electric machines. So far, there have been several attempts to apply nonlinear feedback control to permanent magnet-synchronous spherical motors. However, due to the model’s complexity, few results exist about the associated nonlinear optimal control problem. The proposed nonlinear control methods for permanent magnet synchronous spherical motors make more efficient, precise and reliable the use of such motors in robotics, electric traction and several automation systems.

The treated research topic is central for robotic and industrial automation. Permanent magnet synchronous spherical motors are suitable for several applications, such as actuation in robotics, traction in electric vehicles and use in several automation systems. The solution of the control problem for the nonlinear dynamic model of permanent magnet synchronous spherical motors has many industrial applications and therefore contributes to economic growth and development.

The proposed nonlinear optimal control method is novel compared to past attempts to solve the optimal control problem for nonlinear dynamical systems. Unlike past approaches, in the new nonlinear optimal control method, linearization is performed around a temporary operating point, which is defined by the present value of the system's state vector and by the last sampled value of the control inputs vector and not at points that belong to the desirable trajectory (setpoints). Besides, the Riccati equation which is used for computing the feedback gains of the controller is new, and so is the global stability proof for this control method. Compared to nonlinear model predictive control, which is a popular approach for treating the optimal control problem in industry, the new nonlinear optimal (H-infinity) control scheme is of proven global stability, and the convergence of its iterative search for the optimum does not depend on initial conditions and trials with multiple sets of controller parameters. It is also noteworthy that the nonlinear optimal control method is applicable to a wider class of dynamical systems than approaches based on the solution of state dependent Riccati equations (SDRE). The SDRE approaches can be applied only to dynamical systems which can be transformed into the linear parameter varying form. Besides, the nonlinear optimal control method performs better than nonlinear optimal control schemes, which use approximation of the solution of the Hamilton–Jacobi–Bellman equation by Galerkin series expansions. Furthermore, the second control method proposed in this paper, which is flatness-based control in successive loops, is also novel and demonstrates substantial contribution to nonlinear control for robotics and industrial automation.

This paper aims at identifying crucial factors that affect student satisfaction with synchronous e-learning. For this purpose, a research model comprised of perceived usefulness (PU), perceived ease of use (PEU), computer anxiety (CA), self-efficacy (SE), system accessibility (SA), perceived interaction (PI) and perceived flexibility (PF) was developed.

For the purpose of this research, an online questionnaire was used. All of the measures are adapted from previously validated instruments and adjusted to fit the research aim. Accordingly, the questionnaire resulted in 49 items, which yielded eight constructs. To test the hypothesized model, structural equation modeling was employed on a valid sample of 263 higher education students.

According to the results, PU, PI, CA and flexibility were all found to be significant. PU demonstrated the most contribution following by PF and PI.

Even though this study has included some critical factors theorized to influence e-learning settings, it does not incorporate all elements. In terms of sample size, a bigger sample would be more favorable. Lastly, the study took place during the COVID-19 pandemic, where free movement and social activities were restricted, which may have influenced students' perception of synchronous e-learning.

This research contributes to a greater understanding of the student experience with synchronous e-learning, and its findings can provide relevant stakeholders, particularly e-learning practitioners, with insights into effectively adopting and improving such settings.

This study uses an integrated model of several constructs to investigate student satisfaction in terms of just synchronous e-learning rather than e-learning in general. Several validated instruments were used and tested in a new context and sample. Additionally, the study provides evidence during COVID-19.

This paper investigates the moderating-mediation roles of synchronous and asynchronous learning, as well as virtual self-efficacy between digital learning space experience and continuous use among learners in Ghanaian institutions of higher learning.

A convenience sampling technique was used in the selection of 604 students who answered questions on digital learning space experience, synchronous and asynchronous learning, virtual self-efficacy and learner continuous use within the Greater Accra Region of Ghana. The study employed regression analysis to measure the hypothesized paths.

The findings show that asynchronous learning partially mediates between digital learning space experience and learner continuous use, but the mediating effect of synchronous learning between digital learning space experience and learner continuous use was not significant. Further, virtual self-efficacy significantly moderates the mediated relationship between asynchronous learning and learner continuous use, but the moderated mediated role of synchronous learning was not established in the study.

Generalization of the study findings is limited due to the sampling scope, which was restricted to students of IHL in the Greater Accra Region of Ghana.

In this research, the academic scope of digital transformation was expanded from both digital structure elements and psychological perspectives within the domain of higher education literature.

This paper aims to investigate the effect of learning styles on HyFlex learning towards equity of learning in higher education.

A quantitative approach was used, with data collection through a structured online questionnaire. The study participants were undergraduate students (n = 451) studying at various public and private universities in Indonesia. Measurement analysis is used to test the validity of the instrument used. Analysis of structural equations is used to test the relationships between the constructs under study.

Survey instruments have satisfactory internal validity and consistency. The learning style of students in higher education positively influences the use of HyFlex’s three learning modalities. All three modalities of HyFlex learning positively affect learning equity, especially the asynchronous online modality. However, the synchronous online effect is insignificant. Active/reflective learning styles only affect face-to-face mode but do not significantly affect the two online modalities, synchronous and asynchronous. Some of the learning style dimensions have an indirect effect on equity through three HyFlex learning modalities. Face-to-face and online asynchronous mediate well the indirect relationship between learning style and equity. The impact of gender and higher education status was not shown to strengthen the relationship between learning styles, HyFlex learning modalities and equity.

This study will provide valuable understanding for lecturers, educators and developers to adapt and develop HyFlex learning strategies based on the positive dimensions of the Felder–Silverman learning style that can support equitable and inclusive learning. The study forms a foundation for researchers to investigate more constructs that could improve HyFlex learning in future studies.

This research is a pioneer in using learning styles to investigate trends in using three HyFlex learning modalities, particularly emphasising modalities that can provide equitable learning.

Industrial drives require appropriate control systems for reliable and efficient performance. With synchronous reluctance machines (SynRMs) slowly replacing the most commonly used induction, switched reluctance and permanent magnet machines, it is essential that the drive and its control be properly selected for enhanced performance. But the major drawback of synchronous reluctance motor is the presence of high torque ripple as its design is characterized by large number of variables. The solutions to reduce torque ripple include design modifications, choice of proper power electronic inverter and PWM strategy. But little has been explored about the power electronic inverters suited for synchronous reluctance motor drive to minimize torque ripple inherently by obtaining a more sinusoidal voltage. The purpose of this paper is to elaborate on the potential multilevel inverter topologies applicable to SynRM drives used in solar pumping applications.

The most significant field-oriented control using maximum torque per ampere algorithm for maximizing the torque production is used for the control of SynRM. Simulation results carried out using Matlab/Simulink are presented to justify the choice of inverter and its control technique for SynRM.

The five-level inverter drive gives lesser core or iron losses in the SynRMin comparison to the three- and two-level inverters due to lower Id current ripple. The five-level inverter reduces the torque ripple of the SynRM significantly in comparison to the three- and two-level inverter fed SynRM drives. The phase disposition-PWM control method used for the inverter shows the least total harmonic distortion (THD) levels in output voltage compared with the other level shifted PWM techniques.

Among the available topologies, a fitting topology is proposed for use for the SynRM drive to have minimal THD, minimal current and torque ripple. Additionally, this paper presents various modulation techniques available for the selected drive system and reports on a suitable technique based on minimal THD of output voltage and hence minimal torque ripple.

This paper aims first to describe the most prevalent teachers’ and students’ behaviors in synchronous online classes in emergency remote teaching; second, to discern behavior profiles and third, to investigate what features explain the observed behaviors.

An adapted COPUS observation protocol was employed to observe 292 online classes from 146 higher education teachers.

The most prevalent behaviors were: Presenting for teachers and Receiving for students, followed by Teachers Guiding and Students Talking to Class. Furthermore, cluster analysis showed two groups: Traditional and Interactive. The variables that better explained belonging to the Interactive lecture group were disciplinary area – social sciences and humanities –and teaching in technical institutions.

In a context where higher education institutions intend to project the lessons learned into post-pandemic learning experiences, this study provides observational evidence to realize the full potential expected from online and blended teaching and learning.

Despite the prevalence of synchronous online lectures during COVID-19, there is a paucity of observational studies on the actual behaviors that occurred in this context. Most research has been based on surveys and interviews. This study addresses this gap.

Most educational institutions worldwide have suddenly switched to online instruction due to the outbreak of the COVID-19 pandemic, and English language teaching took its part in this transition. The immediate transition from face-to-face to fully online instruction affects its effective implementation, especially in developing countries like Ethiopia where online learning is in its early stage. Therefore, the main purpose of this study is to investigate postgraduate EFL students’ perceptions and practices of online learning.

This study uses a descriptive survey design. Using simple random sampling, 91 postgraduate EFL students were selected from four universities. Online questionnaires were employed to collect data. To analyze the data, both descriptive (mean and standard deviation) and inferential (one sample t-test) statistics were used.

The findings of the study indicate that the students had favorable perceptions of online learning. Despite the students' positive perceptions, the results of the study showed that the practice of online learning in the universities was limited; especially the practice of synchronous online learning was low.

The results suggest that the concerned bodies at the universities should consider implementing a blended (both synchronous and asynchronous) learning system to deliver an online learning approach.

This is one of the first studies in a higher education context in Ethiopia, which tries to investigate the postgraduate EFL students' perceptions and practices of online learning during the COVID-19 pandemic. The paper is original because it investigated the status of online learning during the pandemic in a developing country like Ethiopia; it provides a real and convincing idea of a new way of learning in the post-COVID-19 context. The study can also be useful for related future research in the context of a pandemic-like COVID-19.

The purpose of this paper is to present the influence of inter-turn short circuit faults (ITSF) on electromagnetic vibration in high-voltage line-starting permanent magnet synchronous motor (HVLSPMSMS).

In this paper, the ampere–conductor wave model of HVLSPMSM after ITSF is established. Second, a mathematical model of the magnetic field after ITSF is established, and the influence law of the ITSF on the air-gap magnetic field is analyzed. Further, the mathematical expression of the electromagnetic force density is established based on the Maxwell tensor method. The impact of HVLSPMSM torque ripple frequency, radial electromagnetic force spatial–temporal distribution and rotor unbalanced magnetic tension force by ITSF is revealed. Finally, the electromagnetic–mechanical coupling model of HVLSPMSM is established, and the vibration spectra of the motor with different degrees of ITSF are solved by numerical calculation.

In this study, it is found that the 2np order flux density harmonics and (2 N + 1) p order electromagnetic forces are not generated when ITSF occurs in HVLSPMSM.

By analyzing the multi-harmonics of HVLSPMSM after ITSF, this paper provides a reliable method for troubleshooting from the perspective of vibration and torque fluctuation and rotor unbalanced electromagnetic force.

HyFlex course design is an effective instructional course design that combines active and transformative learning techniques. HyFlex course design encourages active learning by focusing on interactive activities, discussions, and collaboration. It also allows learners to collaborate effectively and flexibly as a community, providing peer support and opportunities for authentic dialogue and learning experiences. HyFlex course design provides the opportunity for transformative learning through its ability to offer personalized educational experiences to individuals. It facilitates greater customization of the learning experience, allowing individual learners to access tailored educational modules, offer personalized educational experiences to individuals, and effectively develop and build independent and critical thinking skills. This conceptual review, supported by implications from HyFlex literature and triangulated with experts' views undertaking a Delphi study, facilitates understanding the current state of research in HyFlex course design and future application strategies. Existing research has identified HyFlex courses as a promising means of engaging students in active learning. Allowing students to learn through flexibly predesigned mixed online and in-person experiences enables higher levels of student autonomy and supports students in taking more ownership of their learning. This approach can facilitate an understanding of how HyFlex courses can improve active learning practices in higher education. The review study findings identify the reported alignment issues and challenges, suggest four strategies and actions for policymakers and stakeholders, and provide a suggested research agenda for bridging identified research gaps.

Future research can provide evidence of the benefits of HyFlex course design and how flexible course design can address the challenges of traditional face-to-face courses, such as reduced student engagement, lack of student-centered approaches, and limited support for different learning styles. Further research can focus on strategies that can be used to promote active learning in HyFlex courses. Moreover, research can investigate how this kind of course design can equip educators with the skills and knowledge needed to design and implement effective and meaningful active learning experiences. Finally, research can assess the potential impact of HyFlex course design on student outcomes, including performance, satisfaction, and engagement.