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Existing operation methods of air conditioning and mechanical ventilation system ignore actual occupant distribution, resulting in energy waste due to overcooling and overventilation. To create an acceptable indoor environment while reducing energy consumption of operation, occupant-centric control (OCC) strategy has been proposed and developed. In this study, the proposed OCC strategy adjusts on/off of air supply vents and sub-zone air supply parameters according to sub-zone occupancy, involving two sub-zone air supply volume allocation methods, so as to prioritize thermal comfort and air quality in local occupied zone. Computational fluid dynamics was employed to evaluate the OCC strategy's performance in the case of applying stratum ventilation. The results show that the predicted mean vote at 0.6 m height is kept at 0.29–0.53, and the CO₂ concentration at 1.1 m is controlled below 1100 ppm, which can achieve energy savings of 18–51 % (compared to Baseline 1) and 4–16 % (compared to Baseline 2). Moreover, the larger the difference in the number of occupants between sub-zones, the more energy savings the OCC strategy can achieve. It is suggested that sub-zone air supply volume should be allocated according to sub-zone cooling load and the outdoor air ratio in critical sub-zone should be employed to compensate for total outdoor air volume. This study provides an approach to combine the OCC strategy with non-uniform air distribution, offering insights into the balance of energy efficiency and occupied environmental comfort in system operation.

In order to explore reasonable prebedtime interventions to improve the sleep quality of the youth population, this experiment comprehensively investigated the effect of prebedtime footbath on the improvement of youth sleep quality. The experimental conditions of the experimental group were to take a 30-min footbath at 40°C 1 h before bedtime, to compare the experiment with the control group that did not take footbath, and to strictly control other environmental parameters that may affect sleep quality. We recorded the sleep of 16 male subjects using a subjective sleep quality questionnaire and polysomnography (PSG) and recorded their distal skin temperature (DST) and proximal skin temperature (PST) during footbath and sleep using temperature records. The skin temperature data showed that footbath before bedtime helped to increase DST and accelerate heat dissipation from the terminal skin, which in turn increased the distal–proximal skin temperature gradient (DPG), and we found that the DPG of the experimental group was higher than that of the control group for 84.8% of the time during the whole night’s sleep. Both subjective questionnaire and PSG monitoring results showed that sleep quality and sleep calmness could be effectively improved by taking a 30-min 40°C bedtime footbath 1 h before bedtime. The subjective sleep quality questionnaire score of the control group was only 84.1% of that of the experimental group. There were significant differences between the control and experimental groups in total sleep time (TST), sleep-onset latency (SOL), wake after sleep onset (WASO), and arousal index (AI) (p < 0.05). Compared to the control group, the experimental group showed a 43.4-min increase in TST, a 14.9-min decrease in SOL, a 32-min decrease in WASO, a 3.28 beats/hour decrease in AI, and a 9.0% increase in sleep efficiency by performing a prebedtime footbath. This study quantitatively describes the effect of prebedtime footbath on the improvement of sleep quality in young men and provides an effective reference for the rational improvement of sleep quality in young people.

The construction process is a dynamic one, and the complexity of the working conditions and the high level of uncertainty make the construction industry the third most dangerous industry after mining and agriculture. And since the construction industry is vital to the development of a country, safety during construction is of particular importance. A great deal of research, studies and practices have been conducted to reduce potential risks and improve worker efficiency during the construction process. In recent years, with the rapid development of cognitive neuroscience and the integration of medical technology, various wearable monitoring devices have been widely used in the field of building construction for real-time monitoring of workers’ physical and mental conditions. Among them, the application of EEG (electroencephalogram) in the building construction process enables researchers to gain insight into the physical and mental state of construction workers while performing construction tasks. This paper introduces EEG technology and portable EEG monitoring equipment and summarizes its application in monitoring workers’ adverse reactions (emotion, fatigue, psychological burden, and vigilance) and construction hazard identification during the process of construction in recent years, which provides future EEG research in the field of building construction and construction site safety management.