Study on Environment Regulation of Residential in Severe Cold Area of China in Winter: Base on Outdoor Thermal Comfort of the Elderly

Study on the outdoor thermal comfort of college students under different activity intensities in a high-altitude climate zone

Introduction

Research on the outdoor thermal comfort (OTC) of a university campus is beneficial to the physical and mental health of college students.

Methods

In this study, the OTC of students attending Tibet University in Lhasa, which experiences high-altitude cold climate conditions, under different activity intensities was studied using field measurements and a questionnaire survey.

Results

With the increase in activity intensity, the comfort physiologically equivalent temperature (PET) value gradually increased in summer, while the comfortable PET value gradually decreased in winter. The most comfortable PET value is 17.6°C in summer and 11.5°C in winter. The neutral PET of Tibetan college students during outdoor activities in summer was 16.3°C, and the neutral PET of outdoor activities in winter was 12.1°C. Gender and ethnicity had different effects on thermal sensation under different activity intensities. Under vigorous-intensity activities, PET in winter and summer had the greatest influence on thermal sensation. The situation was different under moderate-intensity activity. PET had the greatest influence on thermal sensation in summer, and Tmrt had the greatest influence on thermal sensation in winter.

Discussion

These findings provide a basis for an improved design of the outdoor environment under different outdoor activity intensities in high-altitude areas.

Effect of Environmental Planning on Elderly Individual Quality of Life in Severe Cold Regions: A Case Study in Northeastern China

With the development of urbanization and the ageing population, the improvement of the urban environment and the quality of life (QOL) of the elderly in cities with a cold climate have become critical issues to be addressed. However, only a few studies have focused on this aspect. According to a review of the literature, the contents of the built environment (BE) in severe cold regions are defined as thirteen key factors of four categories (density, environmental aesthetics, outdoor environment, and accessibility) and the QOL of old people consists of three aspects (residential, health, and social satisfaction). This study explores how BE variables are associated with the QOL of older adults by using ordered logit and gologit2 models. The data consist of the results of 1945 questionnaires from field surveys in 11 different residential areas, across two cities in northeastern China. The results show: (1) Walkability in winter, distance to a public park of 400–1000 m, outdoor shelters and seating, less than five buses available, and a mixture of evergreen and deciduous trees are five of the most important variables of BE that have a significant positive impact on QOL compared with other climatic regions; (2) “Pocket parks” and pedestrian walkway safety are appropriate approaches to improve wellbeing under local economic conditions. For public transportation, metro and rail transit systems are encouraged, and some rules are needed to reduce the number of buses in harsh weather conditions; (3) Compared with spatial distribution in other climates, the scope of a 15 min city should be less than 1km in severe cold areas. From the findings, we conclude that there are six possible pattern languages to improve the urban environment, and they can provide information for further study on environmental planning in severe cold regions.

How to design comfortable open spaces for the elderly? Implications of their thermal perceptions in an urban park

Elderly residents are prominent users of urban parks and comfortable open spaces in parks have been shown to improve their physical health and mental well-being. In this study, the thermal perceptions (thermal sensation, thermal comfort and thermal acceptability) of elderly visitors to an urban park in Xi'an, China was investigated using meteorological measurements, questionnaire surveys and activity records. Physiological equivalent temperature (PET) was used to determine thermal benchmarks. Spatial-temporal distributions of the elderly in open spaces were recorded and relationships among elderly residents' thermal perceptions, their age and chronic disease were analyzed. Finally, optimal design strategies for open spaces suitable for the elderly were proposed based on meteorological characteristics, elderly residents' attendance patterns and their thermal perceptions. Results showed that: 1) globe temperature (T_g) and air temperature (T_a) were the primary meteorological factors that influenced elderly residents' thermal sensation while clothing insulation and activity intensity were negatively correlated with their thermal sensation. 2) Attendance was significantly affected by the outdoor microclimate, space functionality and facilities in spaces. The elderly mainly participated in dynamic activities and social interaction. 3) The neutral PET (NPET) was 13.2 °C, with NPET range (NPETR) of 3.1-23.2 °C. The 90% thermal acceptable PET ranged between 10.9 and 25.9 °C, and the preferred PET was 14.4 °C. Compared with the ISO7730 standard, the predicted percentage of dissatisfied (PPD) elderly park users was lower than users of indoor spaces when -1 ≤ MTSV ≤ + 1, indicating that the elderly preferred to conduct activities outside when the environment was comfortable. Additionally, NPET for the elderly with respiratory disease was higher than those with cardiovascular diseases and diabetes. 4) Optimal design strategies for open spaces were proposed for elderly residents based on their physical, physiological and psychological preferences.