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[Display omitted] • Temple skin temperature reflects an increased level of thermal stress in high temperatures. • The cognitive performance significantly changed with the increase in temple skin temperature. • An inverted U-shaped curve demonstrates the relationship between the accuracy of cognitive performance and temple skin temperature. • Introducing the temple skin temperature-cognitive performance(TST-CP) model to predict cognitive performance based on temple skin temperature. • The TST-CP model has demonstrated strong reliability in predicting cognitive performance. The study aimed to explore temple skin temperature as a potential physiological indicator reflecting the impact of high temperatures on cognitive performance. The feasibility of this indicator was substantiated through a thorough analysis of climate-controlled experimental data conducted at varying high temperatures: 33 °C, 37 °C, and 39 °C. The temple skin temperature was carefully monitored during the experiments, alongside cognitive tests that measured work memory, concentration, and neurobehavioral abilities. In total, 1459 valid samples were collected, contributing to the robustness of the study. The results elucidated a noteworthy finding: a significant decline in cognitive test accuracy commenced when the temple skin temperature reached 37 °C (p < 0.05). Intriguingly, the correlation between the relative accuracy of cognitive tests and temple skin temperature showcased a distinctive inverted U-shaped pattern. Employing a quadratic regression model facilitated the quantification of this relationship, yielding coefficients of determination (R2) for the fitted models that were close to or exceeded 0.9. These findings imply that temple skin temperature can be used to assess the effect of high temperature on cognitive performance. Furthermore, this research suggests the promising prospect of employing temple skin temperature for real-time monitoring of job safety in high-temperature environments. [ABSTRACT FROM AUTHOR]

This study investigated the effects of four important microclimate parameters on outdoor thermal sensation and neutral temperature. A long term (almost 2 years) field investigation was conducted at six typical public spaces in Changsha China, with hot-summer and cold-winter climate. During a single investigation of one day (from 9:00 to 18:00), outdoor air temperature, air humidity, global temperature and wind speed were continuously measured at one measuring point. People visiting the public spaces (near the measuring site) were randomly invited to fill out a questionnaire describing their feelings of thermal comfort and other important psychological factors. Based on the field data (7851 samples), relationship between people’s outdoor thermal sensation and the microclimate parameters were quantified. Further, the effect of the microclimate parameters on outdoor thermal sensation and neutral temperatures was analyzed. The results revealed that outdoor microclimate parameters, especially outdoor air temperature, play important roles on outdoor thermal sensation when people stay outdoors. The variation in outdoor microclimate parameters led to the biggest change of outdoor neutral temperature in winter. Seasonal and regional differences in outdoor neutral temperature were found, which reflects different thermal comfort requirements under distinct outdoor microclimate conditions. [ABSTRACT FROM AUTHOR]

Abstract: The indoor air diffusion of a typical office equipped with a floor-standing type air-conditioner (FSAC) in summer was evaluated and optimized. Two existing evaluation indexes, the air diffusion performance index and the energy utilization coefficient, were modified for their more reasonable application in the evaluation on air diffusion performance of a FSAC. And also, a new index, fast cooling effect index, was presented to evaluate the fast-cooling effect. Based on the indoor airflow simulation using computational fluid dynamics, the three indexes were applied to evaluate the air diffusion performance of the FSAC. As a result, the optimal indoor air diffusion types with best thermal feelings, fine energy utilization efficiency and excellent fast-cooling effect were obtained, and also, a control scheme was suggested. [Copyright &y& Elsevier]

Abstract: An evaluation model for individual thermal comfort is presented based on the BP neural network. The train data came from a thermal comfort survey. The evaluation results of the model showed a good match with the subject''s real thermal sensation, which indicated that the model can be used to evaluate individual thermal comfort rightly. Taken a room air conditioner as an example, the application of the NNEM in creating a microenvironment for individual was discussed. The result showed that the NNEM can play an important role of connecting individual thermal comfort with the control on the air conditioner. [Copyright &y& Elsevier]

• A dynamic setting temperature that adapts to climate change was proposed. • The method was based on clothing adjustment behavior which adapts to thermal comfort. • The dynamic setting temperature had significant energy saving potential. • The dynamic setting temperature is useful for intelligent control of air-conditioner. Saving energy consumption of air-conditioning is essential to building energy conservation while satisfying the thermal comfort requirements of indoor environment. On the basis of human clothing adjustment behavior, a dynamic setting temperature (DST) that adapts to climate change was proposed in this paper, i.e. indoor air-conditioning setting temperature changes dynamically with outdoor air temperature; furthermore. A method was established to obtain the DST. The daily mean clothing insulation was predicted according to the historical temperature at first, then indoor thermal comfort temperature was calculated based on the variable clothing insulation, and finally the DST was determined. According to the value or range of predicted mean vote (0, -0.5~0.5, -1~+1) corresponding to the thermal comfort, three levels of DST were defined. The corresponding thermal acceptability rates were 95%, 90% and 73%, respectively. A simulation of DST was conducted in a public building in Changsha, China based on meteorological data of 2017. Three levels of DST ranges were obtained, varied from 20.1 to 27.8 °C in level I, 17.8 to 28.7 °C in level II and 15.4 to 29.7 °C in level III, respectively. The simulation results of operational air-conditioning energy consumption shows that the application of DST could save up to 65.5% of energy consumption compared with the traditional fixed setting temperature (FST), and the operational energy consumption decreased by 59.1% due to the application of level-III DST compared with level-I DST. Therefore, the DST proposed in this paper has significant energy saving potential while meeting the thermal comfort requirements. [ABSTRACT FROM AUTHOR]

• Subjects performed 10 kinds of cognitive tests in the three phase experiments. • The cognitive test scores had significant learning effect. • The speed of all tests and the accuracy of a few tests increased significantly. • The improvement rate of cognitive test speed was higher compared with accuracy. • The learning effect model based on logistic function had higher R2 (> 0.99). This study aimed to identify the law of cognitive test scores with the number of repetitions, and to establish a prediction model that quantitatively describes the changes in cognitive test scores. The experiments were conducted in a chamber that simulated an office environment. Participants performed neurobehavioral, Tsai-Partington, typing and d2 tests at 26 ℃. The speed and accuracy were used to reflect the cognitive test scores. The results demonstrated that a significant learning effect occurred in these cognitive test scores. The speed and accuracy of completing cognitive tests increased as the number of repetitions increased. The majority of cognitive tests could achieve stability after five repetitions and, at most, eight repetitions. The learning effect had different effects on the speed and accuracy. The percentage improvement of the speed was higher compared with accuracy, but it took more attempts to reach stability. The regression model based on the logistic function could accurately quantify the tendency for the variation in cognitive test scores with the number of repetitions. Compared with the power, linear and logarithmic functions, the logistic function had a higher R2(> 0.99). A method for correcting the learning effect of these cognitive tests was proposed based on the prediction model. [ABSTRACT FROM AUTHOR]

Abstract: Although variable-air-volume system (VAVS) can save much energy compared with other kind of HVAC system (e.g. constant-air-volume system (CAVS), fan-coil system (FCS)), it demands more investment. The rate of return of variable-air-volume system, which is closely related to the energy-saving rate of the system, ought to be taken into account by the engineers in the course of design. China has a wide territory and different climates that will impact on the energy-saving rate of variable-air-volume system. To help the engineers have a good idea of the rate of return of variable-air-volume system in different areas of China, it is necessary to establish such program that can evaluate the energy-saving rate of variable-air-volume system compared to constant-air-volume system and fan-coil system. In this paper, the specific energy models of the primary equipments in HVAC system are established, and the evaluation program for the energy-saving of variable-air-volume system compared to constant-air-volume system and fan-coil system are expounded. The parameters in the energy models, which may impact the validity of the evaluation program, can be obtained from the field-testing data or the performance data provided by the product manual. One small office building is taken as an example, the year-round energy simulations of the three kinds of HVAC systems (variable-air-volume system, constant-air-volume system and fan-coil system) of the same building have been made, and the energy-saving of the variable-air-volume system has been evaluated in six cities of China by the program. The evaluation program can also be used to analyze the energy-saving of variable-air-volume system in medium and big office buildings. [Copyright &y& Elsevier]

• A recirculated air curtain was arranged inside a room for transient zonal isolation. • Air curtain was installed on the basis of existing mixed ventilation in the room. • Isolation initially increased and then decreased as discharge velocity increased. • Air curtain performed better when the air was recirculated from the floor below it. • Reducing protected area did not significantly improve regional protection capacity. An air curtain is an aerodynamic barrier for regional isolation and protection; however, research on its application in ventilated rooms is insufficient. This study investigated the effect of a recirculated air curtain on transient contaminant transport when used inside a room with diluted ventilation. The effects of the discharge air velocity, air intake position, and air curtain position were studied using a numerical method. The results were compared with those of diluted ventilation only. The results showed that even when the air curtain recirculated the polluted indoor air, adding a recirculated air curtain based on traditional ventilation significantly reduced the pollution in the protected zone. The containment effect on pollution initially increased and then decreased as the discharge air velocity of the air curtain increased from 0.5 to 4 m/s. A moderate velocity of 1 m/s for a jet width of 0.06 m acted as an effective aerodynamic barrier, with the average concentration in the protected zone reduced by up to 66 % at 600 s. The air intake of the air curtain strengthened the deflection of the air supply jet and vortex in the region. The air curtain exhibited better performance when the air was recirculated from the floor below it. Reducing the protected area did not significantly improve the regional protection capacity. This study guides the joint design of air curtains and air distribution patterns in healthy indoor environments. [ABSTRACT FROM AUTHOR]

Indoor thermal environment design parameters have a significant impact on human thermal comfort, health and building energy consumption. The methods of determining indoor thermal environment design parameters in China and around the world are mainly based on the PMV model. This method often results in certain errors deviations from the actual situation and has difficulty reflecting the differences in the thermal environmental requirements in different climate regions, seasons, building types, etc. This paper proposes a data-driven method based on Chinese Thermal Comfort Database and uses a logistic regression to obtain the indoor air temperature range that 80% of occupants find thermally acceptable under different conditions. The results indicate that the prediction of this model are in good agreement with the actual data and have as higher accuracy in predicting the percentage of thermal acceptability than a linear regression method. This model shows that different regions, seasons, and building types have different acceptable temperature ranges and that the acceptable air temperature ranges are on average 2.0 °C wider than the ISO 7730 and 0.7 °C wider than the GB50736-2012. This method is conducive to the determination of air temperature thresholds and better reflects people's equirements for thermal environment under different conditions. [ABSTRACT FROM AUTHOR]