Effects of different exercise types on outdoor thermal comfort in a severe cold city.

The promotion of China's National Fitness Program has caused an upsurge in the construction of outdoor sports venues and sparked an interest in research on the thermal comfort of people exercising outside. The design of exercise facilities and parks is usually function-oriented, and the spatial layout and arrangement of exercise paths are based on the exercise type. However, few studies compared the thermal comfort of different exercise types. This study investigated seasonal differences in thermal sensation, thermal comfort, and other influencing factors among people who engaged in various types of exercise in a severe cold city in China. The results showed significant differences in thermal comfort among the different exercise types. The acceptable thermal range of exercising people is greater than that of the resting ones. In the cold season, the thermal comfort of different exercise types had a significant correlation with thermal sensation, but not with humidity and wind sensations. On the other hand, the thermal comfort of jogging respondents was more affected by humidity, wind, and sun sensations during the hot season. The modified UTCI range of thermal stress category was proposed as a design reference for the thermal environment of outdoor exercise venues. Overall, this study can help enrich and guide outdoor thermal comfort research in severe cold regions and aid the design of urban exercise spaces.

Study on the multivariate prediction model and exposure level of indoor and outdoor particulate concentration in severe cold region of China.

Atmospheric particulate matter( PM10, PM2.5) has been the main pollutant in most cities of China in recent years, and the exposure concentration is related to the incidence of human diseases and mortality. The time spent indoors is more than 80% for modern people. Therefore, study on the correlation and exposure level of indoor and outdoor atmospheric particles is important. To research the exposure level in the heating season and non-heating season of indoor and outdoor particulate concentration in severe cold region of China, a total of 110 samples of four types of buildings (office, classroom, urban residence and rural residence) in Daqing, a typical city of severe cold region in China, were tested by particle monitor. Based on the indoor and outdoor environmental parameters, multiple linear regression (MLR) and principal component regression (PCR), established the indoor particulate concentration prediction models. The short and long term exposure of different people in different environments in severe cold region of China was analyzed based on the people's time-activity pattern with the measured data and model. The results showed that as for the short term indoor and outdoor exposure of different people, the average combined exposure of urban people in heating season is 60.0% higher than that in non-heating season, and rural people in heating season 30.2% higher than that in non-heating season. As for the long term indoor and outdoor exposure of different people, the annual average combined exposure of urban people was 9.6% higher than that of rural people. While all for urban and rural people, differences in respiratory rates between genders resulted in an average potential dose of 21. 8% higher in male than in female.

Field Study on Indoor Thermal Environments of Monastic Houses and Thermal Comfort of Monks.

Monastic houses are an essential part of the Tibetan monastic system in China. In this study, the monastic houses of Labrang in the Tibetan region of Gannan were used as the research objects. Physical parameters such as indoor temperature, humidity, and radiation temperature of the monastic houses were measured. The measured results were compared with the standard values, while the air temperature was linearly fitted using TSV, PMV, and aPMV. The results show that the temperature inside and outside the monastic houses fluctuates considerably; the theoretical thermal neutral temperature of the tested monks in winter is 22.46 °C, which is higher than the measured thermal neutral temperature in winter of 16.43 °C. When analyzing the results, it was found that the local climate, dress code, and the monks' specific habits all impact the perception of thermal comfort, which creates a discrepancy between the accurate results and the standard values. The above findings provide a more comprehensive reference for the thermal comfort requirements of the monks in cold areas, which can be used as a guide for the improvement and evaluation of the monastic houses in cold areas.

Study of enhanced nitrogen removal efficiency and microbial characteristics of an improved two-stage A/O process.

During the cold winter in northern China, the temperature is generally below 8°C, and low water temperature significantly inhibits biological treatment processes, especially the biological denitrification process. To solve this problem, this study proposed an improved two-stage A/O process with built-in submerged biofilm modules. Experimental water was acquired from the Sanbaotun Wastewater Treatment Plant, which is situated in the city of Fushun, Liaoning Province. After one year of experimental research, the improved two-stage A/O process proved to be significantly better than the traditional two-stage A/O process, especially in winter. In the one-year experiment, the average removal rates of COD, TN, and NH4+-N in the improved two-stage A/O process were 85.2%, 77.6%, and 96.9%, respectively. Microbial properties of the process were studied by means of high-throughput sequencing. High-throughput sequencing was conducted on the biofilm of the improved two-stage A/O terminal aerobic tank and the activated sludge of the conventional two-stage A/O aerobic tank. The result showed that the microbial diversity and abundance of the biofilms were considerably higher than those of the activated sludge during stable operation in winter. Under low-temperature conditions, the main denitrifying bacteria of the improved two-stage A/O process was Terrimonas, belonging to the sphingolipid class of Bacteroides, and the main genus of nitrifying bacteria was Nitrospira, belonging to the nitrite oxidizing bacteria.

A Design Strategy for Energy-Efficient Rural Houses in Severe Cold Regions.

In the past decade, Chinese urban areas have seen rapid development, and rural areas are becoming the next construction hotspot. The development of rural buildings in China has lagged behind urban development, and there is a lack of energy-efficient rural buildings. Rural houses in severe cold regions have the characteristics of large energy exchange, a long heating cycle, and low construction costs. Energy consumption is a crucial issue for rural houses in severe cold regions. How to balance the energy efficiency and building cost become a crucial problem. To solve this problem, we investigate the energy consumption of rural housing in cold regions, using Longquan Village in Heilongjiang Province, northeast China, as a case study. A low-energy design framework is established that considers the spatial layout, building type, enclosure system, and heating system. With the support of project funds, a demonstration house is constructed, and the energy savings performance of the building is investigated during the heating period. The results indicate that the energy savings rate of the demonstration house is 66%. The demonstration building enables local residents to learn construction methods for low-energy houses and promotes energy efficiency.