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To ensure the normal operation of teaching and meet the needs of teaching quality assessment in the COVID-19 situation, universities in various countries have adopted online proctoring for assessment. The epidemic has accelerated the development of online education. Online proctoring, as an integral part of future online teaching, has not yet drawn sufficient attention. To understand students' experiences and attitudes towards initial online proctoring, an extended technology acceptance model was utilised to examine the motivations and barriers that influence students' online proctoring acceptance in terms of technology perception, presence and social influence. Structural equation models were used to analyse data from a questionnaire survey of 760 university students. Results revealed that social influence, social presence and perceived usefulness are the significant predictors of online proctoring acceptance. Social influence and social presence have significant positive effects on online proctoring acceptance through perceived usefulness, and social presence has a positive effect on perceived ease of use. However, perceived ease of use has a significant negative effect, while place presence has no significant effect. Implications, limitations and future work are discussed at the end.

With oilfields enter the late stage of development, which is difficult to extract residual oil in the reservoirs. Microbial oil displacement is favored as an efficient and clean stimulation method. As an important mechanism of the technology, biosurfactants are being studied and applied. Differ from traditional synthetic surfactants, biosurfactants are more practical, economically valuable and environmentally friendly. This article describes the three action mechanisms of biosurfactants and introduces the current research status and technological achievements of glycolipids, lipopeptides, fatty acids, polymers, and phospholipids. Compare the advantages and limitations of each the above, introduce the field application method and effect, and prospect the future development direction of this technology and provide reasonable suggestions. The results show that biosurfactants have obvious advantages, which can change oil water interfacial tension, emulsify crude oil, and achieve wetting reversal, improving crude oil recovery rate. It has enormous development potential in oilfield production, further on-site testing is needed for technology in the future. It is necessary to enhance its compatibility in different types of formations, especially to achieve good results in special reservoirs. By controlling the oil displacement cost, it can achieve the goal of reducing costs, increasing efficiency, and further improving crude oil recovery. [ABSTRACT FROM AUTHOR]

The inherent complexity of listening activities poses considerable challenges to second language listeners. For decades, researchers have been exploring effective strategies to help improve L2 learners' listening proficiency. Note-taking, which is frequently and strategically employed to complete listening tasks and to learn content, has also been examined extensively from various perspectives. However, it seems that little is known about the effect of L2 learners' linguistic choices in note-taking on their listening performance. Employing pedagogical translanguaging as an analytical lens, the current research sets out to investigate whether or not L2 learners' multilingual notes, compared to monolingual notes, significantly enhance their performance in academic listening activities. Conducted in a Chinese university EFL context, this study adopts a mixed-methods approach. A total of 90 participants were assigned to three groups and were asked to take notes in Chinese, English, and a combination of all languages, symbols, drawings, etc., respectively. Data were collected from the results of two listening tasks (a listening comprehension test and a retelling task), a questionnaire survey designed to focus on their attitudes to the linguistic choices they made in note-taking, and the multilingual notes taken. The findings revealed that students who were allowed to make full use of their linguistic and semiotic resources in note-taking were able to perform significantly better in both listening tasks. The same group of students also demonstrated a diverse and flexible mobilization of their multilingual and multimodal assets in the notes they took. This study provides evidence for applying pedagogical translanguaging as an effective approach in designing note-taking instructions. It is suggested that L2 learners should be encouraged to deploy their entire linguistic repertoire when taking notes during listening activities, which could lead to improved performance. [ABSTRACT FROM AUTHOR]

Summary: False data injection attacks can disrupt the steering control actions and make a real threat to both the security and safety of autonomous vehicles. In this paper, a secure event‐triggered lateral control approach of autonomous vehicles subject to actuator attacks is investigated. Firstly, an arbitrary unknown actuator attacks is considered in the secure lateral steering control of autonomous vehicles. Thus, to save communication resources for the limited bandwidth CAN bus, the periodic event‐triggered transmission scheme is utilized, transforming the established lateral steering control into a time‐delay system through the consideration of periodic event‐triggered sampling. Then, an adaptive control compensation scheme is developed to mitigate the malicious effects caused by actuator attacks. The proposed secure control approach is skilled in compensating the unknown attacked steering control actions in an adaptive way. The stabilization criteria under the adaptive secure control law is well derived by Lyapunov–Krasovskii method and some linear inequality matrices operations. At last, the effectiveness of the proposed secure control scheme is verified by some numerical experiments borrowed from a practical vehicle. [ABSTRACT FROM AUTHOR]