Neutral Temperature Research Articles

The Venus Global Ionosphere‐Thermosphere Model (V‐GITM): A Coupled Thermosphere and Ionosphere Formulation

AbstractThis paper introduces the new Venus global ionosphere‐thermosphere model (V‐GITM) which incorporates the terrestrial GITM framework with Venus‐specific parameters, ion‐neutral chemistry, and radiative processes in order to simulate some of the observable features regarding the temperatures, composition, and dynamical structure of the Venus atmosphere from 70 to 170 km. Atmospheric processes are included based upon formulations used in previous Venus GCMs, several augmentations exist, such as improved horizontal and vertical momentum equations and tracking exothermic chemistry. Explicitly solving the momentum equations allows for the exploration of its dynamical effects on the day‐night structure. In addition, V‐GITM's use of exothermic chemistry instead of a strong heating efficiency accounts for the heating due to the solar EUV while producing comparable temperatures to empirical models. V‐GITM neutral temperatures and neutral‐ion densities are compared to upper atmosphere measurements obtained from Pioneer Venus and Venus Express. V‐GITM demonstrates asymmetric horizontal wind velocities through the cloud tops to the middle thermosphere and explains the mechanisms for sustaining the wind structure. In addition, V‐GITM produces reasonable dayside ion densities and shows that the neutral winds can carry the ions to the nightside via an experiment advecting .

Energy Efficiency Assessment of Existing Rural Houses in Nantong Based on Human Thermal Comfort

Current research on rural houses in China mainly focuses on improving energy efficiency, with relatively few studies addressing energy-saving measures and enhancing thermal comfort for residents. Therefore, this paper focuses on existing rural houses in Nantong City, Jiangsu Province, as the research object. Through on-site measurements and questionnaire surveys, it was found that the average indoor temperature of rural houses is 28.5 °C in summer and below 10 °C in winter, failing to meet the comfort needs of the villagers. To further study human thermal comfort, a linear regression method was used to establish an indoor Mean Thermal Sensation (MTS) model for Nantong’s rural houses. The neutral temperature in summer was found to be 26.46 °C, and an adaptive thermal comfort model for rural residents in the Nantong area was established. Through single-factor simulation and orthogonal experiments, the optimal comprehensive energy-saving renovation scheme was proposed. Finally, a typical rural house in Zhangzhuang Village was used as a case for building renovation practice. After the renovation, the number of thermal comfort hours increased by 145 h per year, the thermal comfort compliance rate reached 47.07%, and the overall energy-saving rate was 57.41%.

Use of Microalgae-Derived Astaxanthin to Improve Cytoprotective Capacity in the Ileum of Heat-Induced Oxidative Stressed Broilers.

The gastrointestinal tract has a pivotal role in nutrient absorption, immune function, and overall homeostasis. The ileum segment of the small intestine plays respective roles in nutrient breakdown and absorption. The purpose of this study was to investigate the impact of heat-induced oxidative stress and the potential mitigating effects of an astaxanthin antioxidant treatment on the ileum of broilers. By comparing the growth performance and gene expression profiles among three groups-thermal neutral, heat stress, and heat stress with astaxanthin-thermal neutral temperature conditions of 21-22 °C and heat stress temperature of 32-35 °C, this research aims to elucidate the role of astaxanthin in supporting homeostasis and cellular protection in the ileum. Results showed both treatments under heat stress experienced reduced growth performance, while the group treated with astaxanthin showed a slightly lesser decline. Results further showed the astaxanthin treatment group significantly upregulated in the cytoprotective gene expression for HSF2, SOD2, GPX3, and TXN, as well as the upregulation of epithelial integrity genes LOX, CLDN1, and MUC2. In conclusion, our experimental findings demonstrate upregulation of cytoprotective and epithelial integrity genes, suggesting astaxanthin may effectively enhance the cellular response to heat stress to mitigate oxidative damage and contribute to cytoprotective capacity.

Research on the effect of exercise behavior on thermal comfort and heating degree days in sports buildings

The exercise behavior has a significant impact on thermal comfort and energy consumption in heating buildings. It is crucial to strike a balance between building energy efficiency and indoor thermal comfort. In this study, we assessed thermal comfort during exercise under indoor conditions in winter by testing the exercise routine of 60 subjects and calculating the number of heating degree days and optimizing the heating cycle. The results showed that exercise behavior significantly affects thermal comfort, with the thermal sensory zone corresponding to thermal comfort shifting and expanding towards the neutral and cooler side. The actual thermal comfort range of the subjects expanded (14.5–17.1 °C) compared to the thermal comfort criterion, suggesting that exercise behavior enhanced the subjects' adaptive capacity. Specifically, at temperatures below thermal neutral (15.8 °C), subjects exhibited a high level of environmental satisfaction, reaching at least 80 %. Additionally, subjects demonstrated thermal 'superconductivity,' with preferred and comfort temperatures approximately 0.8 °C and 0.5 °C lower than the thermal neutral temperature, respectively, indicating a preference for neutral or slightly cooler environments in winter. Furthermore, the base temperature (15.7 °C) was 2.3 °C lower, indicating that heating degree days 18 significantly overestimated heating demand by a factor of at least 1.4. The upper and lower indoor heating set point temperatures (15–17 °C) are about 1–7 °C and 1–3 °C lower than the Chinese building energy efficiency standards, respectively, demonstrating superior energy efficiency in the context of exercise behavior.

Investigating the impact of a large river and its surrounding contextual conditions on pedestrians’ summer thermal perceptions in a Cfa-climate city

Thermal comfort studies are usually employed to find subjective thermal responses [indicated by neutral temperature (NT), i.e. the temperature with no thermal stress] of residents from a region towards thermal environments. According to the recently published works in the literature, NTs are affected by many factors, such as geographical location and microenvironments. To elucidate the origins of these effects, the impact of microenvironment elements around a water surface on pedestrians’ thermal perceptions was systematically investigated in this work. The Fujiang River (FJR) in Mianyang City was taken as the sample site. The municipal meteorology station is located next to the site by around 2.5 km. By performing meteorology measurements combining questionnaires, it was found that the riverside NT (indicated by physiologically equivalent temperature, PET) of Mianyang in the summer of 2023 was 21.4 °C. The relationship between the distance from the water (DFW) and NT was quadratic linear. The same phenomenon took place by using either PET or Universal Thermal Climate Index (UTCI) indexes. Meanwhile, the meteorological contexts also affected NTs, including relative humidity (RH) and air velocity (Va). Regarding RH, the NPET increased from 15.2 °C (RH = 50%) to 26.9 °C (RH = 90%). In contrast, the NPET dropped from 23.0 to − 50.6 °C when the Va increased from 0.2 to 2.5 m/s, respectively. From our analysis, it was demonstrated that human thermal responses are significantly affected by both the microenvironmental and meteorological backgrounds around the water surface. Our work provides valuable insights for the proper use of water surfaces in urban design for adjusting thermal comfort.

A study of street trees and their effects on pedestrians’ perceptions during summer

Poor thermal and light climates can have significant negative effects on human living qualities. Exploring sustainable ways to address these issues is an urgent task, and at the street level, trees pose a potential solution. This study aimed to determine the effect of street trees on pedestrians’ physiological comfort under different conditions. This was accomplished by field surveys, including questionnaires distributed at several forested streets in the Qingbaijiang District (QBD), a suburban area of Chengdu, China. Data analysis showed that people had different responses towards either physical or meteorological factors. They responded differently to various environmental factors, and the responses varied over physical and meteorological contexts. It was found that pedestrians’ neutral temperature and lighting levels were 28.64 °C, as indicated by physiologically equivalent temperature (PET, °C), and 0.91 klx, as indicated by illumination (klx). The percentage of people in favor of larger tree crowns increased considerably for PET (from 60 % at 30 °C to 90 % at 45 °C) and illumination (from 30 % at 0 klx to 100 % at 20 klx) elevations under small-sized trees. People preferred larger crowns and shorter trunks as they made them more comfortable. Their responses were also different for various PETs and daily periods. This is evident from the change in either thermal sensation vote (TSV) or overall comfort vote (OCV). The increase of either PET or illumination might result in TSV increase and OCV decrease. In relative terms, tree crown sizes (diameter, TCD) had a significant influence on pedestrians’ comfort. Increasing TCD by 1 m resulted in a TSV reduction of 0.449 and/or an OCV increase of 0.475 (sig. < 0.001). Results from this study may aid in future urban design and forestation works with the goal of improving pedestrians’ comfort.

Winter indoor thermal environment and livability analysis of traditional residential houses in northeast Sichuan, China

With the rapid development of the national economy, increasing attention has been given to the living environment in rural areas, especially indoor thermal and wind environments. This study conducted on-site measurements and questionnaire surveys during winter in the indoor environment of five villages in northeastern Sichuan. Eighty-nine traditional residences were selected to investigate their fundamental characteristics, indoor thermal environment, humidity conditions, and comfort levels. Questionnaires and comparative experiments were also conducted with natives and locals. This combination of objective data and subjective feedback provides a comprehensive perspective for assessing the indoor thermal environment. The results showed that when expressed as neutral temperature and humidity, the temperature difference was 2.36 °C, with little humidity difference. Residents exhibited higher tolerance towards the local thermal and humidity environment than nonlocal volunteers, who showed greater sensitivity to it. In addition, residents had a Predicted Mean Vote (PMV) value of −0.69 and a heat acceptance value of −1.78, while non-local volunteers had a PMV value of −0.76 and a heat acceptance value of −1.32. A detailed evaluation and analysis of the relationship between the indoor thermal environment and human comfort of local residential houses was carried out, providing technical guidance for energy conservation and thermal insulation of local buildings.

Disk Images of Neutral Temperature From the Global‐Scale Observations of the Limb and Disk (GOLD) Mission

AbstractObservations of far‐ultraviolet (FUV) dayglow by the Global‐scale Observations of Limb and Disk (GOLD) mission provide an opportunity for quantifying the global‐scale response of the thermosphere to solar extreme‐ultraviolet variability and geomagnetic activity. Relative temperature changes can be measured by monitoring changes in the rotational structure observed in molecular nitrogen Lyman‐Birge‐Hopfield (LBH) band emissions. We present a new technique for deriving effective neutral temperatures from GOLD FUV observations using optimal estimation fits to spectra containing LBH band emissions. We provide an overview of the theoretical basis for the GOLD Level 2 TDISK algorithm. Effects on derived effective neutral temperatures from instrument artifacts and particle background are reviewed. We also discuss GOLD Level 1C DAY and Level 2 TDISK data products and present representative examples of each. We show that effective neutral temperatures vary with local time, exhibit a strong dependence on season and solar zenith angle, and correlate strongly with geomagnetic and solar activity. Finally, we present results from a preliminary data product validation that show good agreement with coincident GOLD exospheric temperatures and predictions from a global reference atmospheric model.

From perception to prediction: A comparative study of thermal comfort assessment techniques in school facilities

Indoor environmental quality (IEQ) significantly affects learning, health, and productivity in educational buildings, particularly classrooms. Thermal comfort is crucial to IEQ in classrooms, and various approaches have been developed to assess it. This study compares subjective evaluation, fieldwork measurement, and simulation methods in naturally ventilated secondary school classroom environments in Abuja, Nigeria. It evaluates their reliability, validity, advantages, and limitations. In achieving this objective, fieldwork measurements, questionnaire surveys, and building simulations were conducted in 83 classrooms with 2758 respondents. The data were subjected to descriptive and inferential statistical analysis using the analytical software programs SPSS version 23 and Microsoft Excel. The study found that the Actual Mean Vote (AMV) comfort operative temperature for classrooms was 28.7 °C. Findings from the comparative analysis of the methods indicate that the PMV generally overestimates students’ thermal sensation and that the fieldwork measurement Predicted Mean Votes (PMVf) undervalues the neutral temperature by 4.2 °C. In contrast, the computer-simulated Predicted Mean Votes (PMVs) undervalues it by 3.9 °C. The study found that all three methods are valid and reliable, with some advantages and limitations, depending on the assessment’s specific context and goals. The findings provide valuable insights into improving indoor environmental quality and occupant satisfaction in educational buildings, contributing to the discourse on assessing thermal comfort in classrooms and informing the development of more effective assessment methods. The systematic comparison of these methods addresses a notable gap in the literature, providing practical insights to optimize thermal conditions in learning environments.

Effect of background wind and dissipation processes on the semidiurnal component of atmospheric solar tides

The equations governing the neutral wind velocities and temperature, which depict the oscillations of atmospheric tides, incorporate various elements of the atmosphere. These factors comprise background wind, temperature profiles, and the atmosphere’s composition, including ozone, oxygen, carbon dioxide, water, etc. The current work describes the method of solution of the atmospheric tidal model and investigates the effects of background wind and dissipation processes on the migrating semidiurnal tides during the March equinox. Thermal heating due to water vapour absorption in the troposphere, ozone in the stratosphere and oxygen absorption in the thermosphere is considered in this model. Furthermore, the model takes into account the various dissipation processes (i.e. ion drag and Hall coefficients, Newtonian cooling, divergence of momentum and heat fluxes due to molecular and eddy diffusion) and background wind. The semidiurnal tidal features obtained from the present model match well with the Global Scale Wave Model (GSWM-98). The bar charts are presented to quantify the effects of different parameters on horizontal winds for altitudes below 100 km and above 100 km, separately. It reveals that the background wind plays a vital role in deciding the semidiurnal tidal amplitudes of zonal and meridional winds. Momentum and heat flux coefficients also have a significant influence on semidiurnal tides. At higher altitudes (>100 km), the ion drag reduces the amplitude of semidiurnal tides considerably.

Associations between residential daytime indoor temperature and self-reported sleep disturbances in UK adults: A cross-sectional study

BackgroundIn the past few decades, research on the association between indoor temperature and sleep has primarily used laboratory rather than field data collected in epidemiological cohorts. MethodsSecondary data on 2493 individuals aged 43 years was obtained from the National Survey of Health and Development (NSHD). Logistic regression models were used to investigate the associations between temperatures (indoor at home, spot measurement when the nurses visited during the day; and outdoor, monthly average) and self-reported sleep disturbances, adjusting for socio-demographics, health variables, housing variables, and temperature-related variables. ResultsAssociations were found between daytime indoor temperature with difficulty initiating (OR: 0.95, 95%CI: 0.91–0.98) and maintaining sleep (OR: 0.96, 95%CI: 0.93–0.99). Compared with neutral indoor temperatures (17–28 °C), low indoor temperature (≤17 °C) was associated with difficulty initiating sleep (OR: 1.79, 95%CI: 1.21–2.65). Stratified analysis results across tertiles showed that associations with difficulty initiating (OR: 0.87, 95%CI: 0.77–0.99) and maintaining sleep (OR: 0.88, 95%CI: 0.79–0.98) were observed respectively in the lowest (≤20 °C) and highest tertile (≥23 °C) of indoor temperature. There was no association between outdoor temperature and self-reported sleep disturbances in this study. ConclusionIn this first UK-based epidemiology study investigating temperature and sleep, self-reported sleep disturbances were associated with residential daytime indoor temperatures. Low indoor temperature had significantly higher odds ratio for difficulty initiating sleep compared with the neutral indoor temperature. A warmer indoor environment might be more suitable for sleep maintenance than sleep initiation. Indoor temperature in this study was a superior indicator of sleep disturbances than outdoor temperature. Although these findings are based on a UK sample, they may be relevant to other high-income settings with similar housing stock and climatic conditions.

An Observational Case Study of a Radiation Fog Event

A micrometeorological fog experiment was carried out in Budapest, Hungary during the winter half year of 2020–2021. The field observation involved (i) standard meteorological and radiosonde measurements; (ii) surface radiation balance and energy budget components, and (iii) ceilometer measurements. 23 fog events occurred during the whole campaign. Foggy events were categorized based on two different methods suggested by Tardif and Rasmussen (2007) and Lin et al. (2022). Using the Present Weather Detector and Visibility sensor (PWD12), duration of foggy periods are approximately shorter (~ 9%) compared to ceilometer measurements. The categorization of fog based on two different methods suggests that duration of radiation fogs is lower compared to that of cloud base lowering (CBL) fogs. The results of analysis of observed data about the longest fog event suggest that (i) it was a radiation fog that developed from the surface upwards with condition of a near neutral temperature profile. Near the surface the turbulent kinetic energy and turbulent momentum fluxes remained smaller than 0.4 m2 s–2 and 0.06 kg m–1 s–2, respectively. In the surface layer the vertical profile of the sensible heat flux was near constant (it changes with height ~ 10%), and during the evolution of the fog, its maximum value was smaller than 25 W m–2, (ii) the dissipation of the fog occurred due to increase of turbulence, (iii) longwave energy budget was close to zero during fog, and a significant increase of virtual potential temperature with height was observed before fog onset. The complete dataset gives an opportunity to quantify local effects, such as tracking the effect of strengthening of wind for modification of stability, surface layer profiles and visibility. Fog formation, development and dissipation are quantified based on the micrometeorological observations performed in suburb area of Budapest, providing a processing algorithm for investigating various fog events for synoptic analysis and for optimization of numerical model parameterizations.

Experimental evaluation of thermal environment built by decoupled radiant cooling system with low radiant cooling temperature

Decoupled radiant cooling system (DRCS)1, which utilizes an infrared-transparent membrane to isolate the radiant surface from the ambient air, can provide radiant cooling temperature below the dew point to prevent condensation and increase cooling capacity. However, whether the thermal environment built by DRCS with low radiant cooling temperature meets thermal comfort needs further investigation. This includes: 1) Do the environment parameters meet the comfort standard? 2) How do subjects evaluate the environment's comfort? Thus, environmental monitoring and questionnaire surveys were conducted to evaluate the thermal environment of DRCS in summer. Initially, the environment parameters were measured and 32 subjects were recruited to perform subjective and physiological response tests. Further, the environment was evaluated using thermal comfort models and thermal sensation votes. Finally, the applicability of the predicted mean vote (PMV) model was examined by comparing actual and predicted thermal sensations. The results confirmed that thermal environment built by DRCS satisfied the ASHRAE Standard criteria. The neutral operative temperature was around 24.8°C and the comfort environment was achieved between 23.3°C and 26.5°C. Moreover, PMV model has a high accuracy in predicting the thermal sensation of DRCS.

Understanding Health-Related Motivations for Urban Food Self-Production in the Light of Semantic Fields Analysis.

One of the contemporary challenges facing urban areas is the necessity to identify novel approaches to resident involvement in solution creation, with a particular focus on ensuring the best possible nutrition. By investigating the process of co-participation of city dwellers in a unique education project, this paper aims to gain a deeper understanding of the health-related motivations that underpin the decision of early adopters of the implemented technological innovations to join the social experiment. The qualitative study employed purposive sampling and in-depth interviews conducted in two waves, the first between October and November 2022 and the second between September 2023 and January 2024. The study comprised 42 participants drawn from two communities of residents in Łódź and Warsaw, Poland. Transcriptions of the interviews were carried out using semantic field analysis, employing a quantitative approach that counts the frequency of keyword occurrences. Three categories of semantic fields were identified: associations, oppositions, and actions toward the subject, including positive, neutral, and negative temperatures. The findings demonstrate that the health concerns of residents are a pivotal factor in their decision to participate in urban food self-production initiatives, given their limited access to nutritious and healthy vegetables. This is related to several factors, including restrictions related to urbanization and the displacement of local suppliers, lifestyle, and the fast pace of urban life. The dissemination of innovative solutions for growing food in urban environments could, therefore, facilitate awareness-raising and motivation to alter the dietary habits of inhabitants.

Integrating the Living Wall with Mechanical Ventilation to Improve Indoor Thermal Environment in the Transition Season

A living wall, when integrated with a mechanical ventilation system, can effectively improve the indoor thermal environment and reduce indoor CO2 concentration during the transition season. In this study, a control experiment was conducted to analyze the effect of a living wall integrated with mechanical ventilation (LW-V) on indoor air quality. During the experiment, indoor air temperature, relative humidity, indoor air speed, and CO2 concentration were measured, while the skin temperature was monitored and subjective questionnaires were administered to 60 subjects. The results show that the indoor environment was effectively improved by employing the LW-V system, with the average indoor temperature decreasing by 1.45 °C, while relative humidity increased by 19.1%. Due to the plant photosynthesis, CO2 concentrations were reduced by 13.83 ppm. Meanwhile, the mean skin temperature was reduced by 0.18 °C and was closer to the neutral mean skin temperature. Questionnaire analysis reveals the LW-V system improved overall air freshness sensation and thermal comfort level by 1.09 and 0.53, respectively. The LW-V system improved the indoor thermal environment as well as air quality during the transition season significantly.

Optical characterization of nanosecond-pulsed discharge in liquid nitrogen

We report the optical characterization of nanosecond-pulsed plasma ignited directly in liquid nitrogen. Using imaging and optical emission spectroscopy, we estimate neutral temperatures and densities, as well as local electric field values, and the obtained results indicate that the discharge develops via streamer (‘electronic’) mechanism. We show that millimeter-scale plasma propagates in liquid nitrogen at velocities of ∼500 km s−1 with the corresponding required local electric fields as high as 25 MV cm−1, while the estimated local electric fields in the ‘core’ of the discharge are around 6–8 MV cm−1 (corresponding to reduced electric field values of 600–1000 Td). The neutral and electron densities in the ‘main body’ of the discharge were estimated using broadened argon lines, indicating that the neutral densities in the near-electrode region are around 1020 cm−3 (tens of atmospheres), while the maximum recorded temperature is just a few tens of degrees above the surrounding liquid. Electron densities were estimated to be ∼1017 cm−3, about two orders of magnitude lower than those measured for water discharge.

Field Investigation on Adaptive Thermal Comfort in Rural Dwellings: A Case Study in Linyi (China) during Summer

A large number of people in China still live in rural villages. The indoor environment of these rural dwellings directly affects the quality of life of the occupants. Nevertheless, constrained by the quality of dwelling construction, rural buildings have poorer indoor environments and, at the same time, have a higher operating energy consumption. However, inadequate attention has been given to the summer thermal environment in cold regions. This work has been carried out around the thermal environment of rural residences in cold regions during summer. Field measurements, questionnaires, and data analysis were used in this study. We recorded the indoor and outdoor thermal environment parameters on a typical summer day in the Linyi rural area. Moreover, the subjective sensations and thermal adaptive behaviors of the participants were recorded in detail with a questionnaire. Linear regression showed that the neutral temperature for residents in summer was 27.52 °C, with acceptable temperatures ranging from 25.14 °C to 29.9 °C. Age and gender differences were found to affect the occupants’ sensation of thermal comfort and humidity, as well as their thermal adaptive behavior. In addition, a thermal adaptive model has been constructed in the study, which will further enrich the thermal adaptive investigation and provide a scientifically sound reference for the renovation and development of the local rural areas.

Variations in Gender Perceptions of Summer Comfort and Adaptation in Colonial Revival-Style Homes

Past investigations have assessed gender variations in thermal comfort and adaptation in different buildings. However, no reported study has evaluated differences in gender perceptions of the thermal environment in US Colonial Revival-style homes. As a result, this study aims to provide an understanding of variations in gender perceptions of summer comfort and adaptation in the buildings. The study evaluated data collected during the field studies of thermal comfort (FSTC), including physical measurements of environmental variables and subjects’ votes. In this study, 67% females and 33% males participated in the field surveys in summertime. The mean neutral temperature of 25.5 °C and preferred temperature of 24.9 °C were noted for females. For males, the mean neutral and preferred temperatures of 25.8 °C and 25.6 °C were observed. Females feel neutral and prefer “no change” to the thermal environment at lower temperatures than males. A difference of 0.3 °C was noted between the average heat indices for females and males. Male respondents who feel warm perceive less air quality more than females. Females and males who perceive being thermally comfortable also perceive good air quality. Females and males who are thermally comfortable rated air humidity to be acceptable. There are similarities and differences between gender perceptions of the thermal environment. The investigation suggests interventions that can help users regulate their skin temperatures and use control measures that are sensitive to clothing insulation. The research also calls for policies that can promote building users’ pivotal adaptive measures to improve their indoor thermal environment. The study enhances our understanding of sustainable indoor environments and how to improve living conditions and adaptive modifications among different groups of occupants in buildings.

Research on Summer Indoor Air Conditioning Design Parameters in Haikou City: A Field Study of Indoor Thermal Perception and Comfort

Escalating global climate change and the intensification of urban heatwaves have led to an increase in summer air conditioning cooling energy consumption. This phenomenon is particularly critical in tropical regions, as it may trigger an energy crisis. The rational setting of indoor thermal design parameters can help conserve energy to the maximum extent while ensuring thermal comfort for occupants. This study selected Haikou City, a unique tropical city in China, as the research location. Indoor environment measurements and a questionnaire survey were conducted with participants, and the outdoor thermal environment sensitivity, population attributes and differences in thermal sensation, thermal neutral temperature, and comfort range were calculated and analyzed. The following results were obtained. Based on the overall population, long-term residence, and temporary residence classification, the indoor thermal comfort needs of residents in tropical cities in Haikou were effectively identified. The actual thermal neutral temperature of the overall population is 25.7 °C, and 90% of the acceptable thermal comfort temperature range is 23.2 °C–28.0 °C. The actual thermal neutral temperature of the regular residents is 27.3 °C, and 90% of the acceptable thermal comfort temperature range is 23.3 °C–31.4 °C. The actual thermal neutral temperature of the temporary population is 25.5 °C, and 90% of the acceptable thermal comfort temperature range is 23.0 °C–28.0 °C. These research results have an important reference value for improving the setting of the temperature of air conditioning in tropical areas in summer and further reducing energy consumption, which is conducive to sustainable development.

Fluid simulation of atmospheric argon RF dielectric barrier discharges: Role of neutral gas temperature

For atmospheric argon RF dielectric barrier discharges, a self-consistent one-dimensional fluid model based on the drift-diffusive approximations of the particles is established to investigate the role of the neutral gas temperature on the discharge process and the plasma characteristics. A finite difference method is used to solve numerically the model, and the numerical results are obtained for the cases that the neutral gas temperature varies from 300 to 600 K. It shows that an increase in the neutral gas temperature causes a decrease in the ionization rate peak and a decrease in the plasma density, but the electric field and the electron temperature do not change very much. Moreover, the discharge mode transition from α mode to α-γ mode occurs because the growing ion flux induces more secondary electron flux, even if the ions entering the sheaths decrease. In addition, the ground state ionization and the ground state excitation are the main collisions in the argon discharges. When metastable atoms are focused on, the three-body quenching is also an important collision progress.