Browsing by Author "Wang, Lei"

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    Exploring a chemical input free advanced oxidation process based on nanobubble technology to treat organic micropollutants
    (Elsevier, 2023-11-04) Wang, Bangguo; Wang, Lijing; Cen, Wenxi; Lyu, Tao; Jarvis, Peter; Zhang, Yang; Zhang, Yuanxun; Han, Yinghui; Wang, Lei; Pan, Gang; Zhang, Kaili; Fan, Wei
    Advanced oxidation processes (AOPs) are increasingly applied in water and wastewater treatment, but their energy consumption and chemical use may hinder their further implementation in a changing world. This study investigated the feasibility and mechanisms involved in a chemical-free nanobubble-based AOP for treating organic micropollutants in both synthetic and real water matrices. The removal efficiency of the model micropollutant Rhodamine B (RhB) by oxygen nanobubble AOP (98%) was significantly higher than for air (73%) and nitrogen nanobubbles (69%). The treatment performance was not significantly affected by pH (3–10) and the presence of ions (Ca2+, Mg2+, HCO3−, and Cl−). Although a higher initial concentration of RhB (10 mg/L) led to a slower treatment process when compared to lower initial concentrations (0.1 and 1 mg/L), the final removal performance reached a similar level (∼98%) between 100 and 500 min. The coexistence of organic matter (humic acid, HA) resulted in a much lower reduction (70%) in the RhB removal rate. Both qualitative and quantitative analysis of reactive oxygen species (ROSs) using fluorescent probe, electron spin resonance, and quenching experiments demonstrated that the contributions of ROSs in RhB degradation followed the order: hydroxyl radical (•OH) > superoxide radical (•O2−) > singlet oxygen (1O2). The cascade degradation reactions for RhB were identified which involve N-de-ethylation, hydroxylation, chromophore cleavage, opening-ring and final mineralisation processes. Moreover, the treatment of real water samples spiked with RhB, including natural lake water and secondary effluent from a sewage works, still showed considerable removals of the dye (75.3%–90.8%), supporting its practical feasibility. Overall, the results benefit future research and application of chemical free nanobubble-based AOP for water and wastewater treatment.
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    Human performance assessment of a single air traffic controller conducting multiple remote tower operations
    (Wiley, 2019-11-13) Kearney, Peter; Li, Wen-Chin; Zhang, Jingyi; Braithwaite, Graham; Wang, Lei
    The innovative concept of multiple remote tower operations (MRTO) can maximize cost savings by applying video panorama‐based remote tower working positions, which can facilitate fewer air traffic controllers (ATCO) to provide the air traffic services (ATS) function for more airports. Five subject‐matter experts, qualified remote tower ATCOs, participated in this research work by applying the human error template (HET) and comparing workload between physical tower operations and MRTO using NASA‐TLX (Task Load Index). The results demonstrate that augmented visualization provided sufficient technical support for a single ATCO to perform tasks originally designed to be performed by four ATCOs, however, the demands of the associated multiple tasks induced significant workload. There were significant differences in ATCOs’ mental demand, temporal demand, effort, and frustration between MRTO and physical tower operations. This innovative technology may induce human–computer interaction (HCI) issues that impact ATCO's perceived workload. This creates a need for further research on how to manage ATCO's workload in a multiple remote tower environment. This research work provided scientific evidence that MRTO can achieve the objectives of Single European Sky Air Traffic Management Research program. The findings can be applied to both ATCO training design and remote tower system design.
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    Visual scan patterns reflect to human-computer interactions on processing different types of messages in the flight deck
    (Elsevier, 2019-04-28) Li, Wen-Chin; Zhang, Jingyi; Le Minh, Tam; Cao, Jiaqi; Wang, Lei
    The flight deck of commercial aircraft is sophisticated and searching for the necessary information at the right time is sometimes challenging. This research investigates pilot's visual parameters while interacted with two different designs of crew alerting system by eye tracking technology. There are 24 aviation professionals that participated in this experiment including commercial pilots, private pilots and avionic engineers. Compared with traditional design, the new integrated design applied proximity compatibility principles to assist pilots in searching necessary information to deal with urgent situations. The results demonstrated that the integrated design is superior to traditional design in providing accurate instructions as determined by visual behaviors. However, the integrated design increases pilot's situation awareness by redirecting attention from current task to the most critical task with the cost of a longer total fixation duration time. Pilot's visual parameters demonstrated significant differences while interacting with PFD mainly numeric, ND mostly by symbols and EICAS with presented text messages. Therefore, flight deck design has to adopt a holistic approach as pilot's visual attentions is shifting among all types of different displays to gain situation awareness rather than focus on only one display. The design of integrated EICAS can provide detailed instructions to deal with urgent situations which induced higher cognitive loads as pilot's pupil dilation is significant bigger than interacted with traditional design. By eye tracking technology, it is applicable to design human-centred flight decks to improve safety and human performance in aviation.