A review of mitigating strategies to improve the thermal environment and thermal comfort in urban outdoor spaces

In the context of global climate change and accelerated urbanization, the deterioration of the urban living environment has had a serious negative impact on the life of residents. However, studies on the effects of forms and configurations of outdoor spaces in residential areas on the outdoor thermal environment based on the particularity of climate in severe cold regions are very limited. Through field measurements of the thermal environment at the pedestrian level in the outdoor space of residential areas in three seasons (summer, the transition season and winter) in Harbin, China, this study explored the effects of forms and configurations of three typical outdoor spaces (the linear block, the enclosed block, and the square) on the thermal environment and thermal comfort using the Physiologically Equivalent Temperature (PET). The results show that the thermal environment of all outdoor space forms was relatively comfortable in the transition season but was uncomfortable in summer and winter. The full-enclosed block with a lower sky view factor (SVF) had a higher thermal comfort condition in summer and winter. The linear block with higher buildings and wider south–north spacing had a higher thermal comfort condition in summer and winter. When the buildings on the south side were lower and the south–north spacing was wider, the thermal environment of the square was more comfortable in winter.

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Analyzing the Effect of Water Body on the Thermal Environment and Comfort at Indoor and Outdoor Spaces in Tropical University Campus

International Journal of Environmental Science and Development ◽

10.18178/ijesd.2021.12.10.1352 ◽

2021 ◽

Vol 12 (10) ◽

pp. 282-288

Author(s):

Farhadur Reza ◽

◽

Shoichi Kojima ◽

Wataru Ando

Keyword(s):

Thermal Comfort ◽

Thermal Environment ◽

Outdoor Thermal Comfort ◽

University Campus ◽

Clothing Insulation ◽

Comfort Index ◽

Outdoor Spaces ◽

Globe Temperature ◽

And Performance ◽

University Spaces

Water bodies play a significant role in its surrounding thermal environment. Thermal comfort in university spaces is critical that affects the students’ health and performance as well as the staffs. This study investigated thermal environment and comfort near lakeside and non-lakeside tropical university spaces. Standard Effective Temperature (SET*) have been calculated using recorded air temperature, relative humidity, globe temperature, air velocity, clothing insulation and metabolic rate to evaluate the thermal comfort in outdoor and indoor spaces. The effects of weather parameters have been clearly visible on the comfort index. The calculated SET* values indicate that the outdoor thermal comfort near a lake is much closer to the standard comfort zone than non-lakeside outdoor space. In the case of indoor thermal comfort, however, slightly a different scenario has been observed. To achieve the desirable indoor thermal environment, some design considerations are recommended based on findings.

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A Seasonal Field Investigation to Perceive Outdoor Thermal Comfort and Thermal Adaption at Malacca Tourist Area- A Pilot Test

10.20944/preprints202102.0370.v1 ◽

2021 ◽

Author(s):

Golnoosh Manteghi

Keyword(s):

Thermal Comfort ◽

Seasonal Variations ◽

Thermal Environment ◽

Thermal Sensation ◽

Outdoor Thermal Comfort ◽

Utilization Rate ◽

Equivalent Temperature ◽

Physiological Equivalent Temperature ◽

Outdoor Spaces ◽

Different Seasons

Season plays a key role in the development of outdoor spaces for pedestrians in hot humid cities. This research studies the influence of seasonal variations on pedestrian thermal comfort on the pedestrian level by means of meteorology and field observations of selected footpaths in the major tourist area of Malacca. This experiment was carried out on selected clear calm days indicative of each season during the development of a research project, and hourly meteorological transects from 10:00 am to 6:00 pm and questioned 200 respondents on their thermal awareness, comfort, and preferences were conducted. Adaptation, thermal comfort vote, thermal preference, age, season and hour of the day were significant non-meteorological factors, apart from meteorological information. The findings of analyzes showed that the thermal experience and expectation existed and in different seasons people changed perceptions for the outside thermal environment. Almost 80% local tourist and 55 % international tourist was accepted Physiologically Equivalent Temperature (PET) range affected by the local climate and thermal adaptation. The subjective thermal sensation on physiological equivalent temperature generated an acceptable physiological equivalent temperature of 32.6°C to 36.8°C based on the seasonal variations for Malacca tourist zone in Malaysia. These findings shed light on the optimal design of outdoor spaces for increasing the utilization rate. The seasonal variation must be taken into account so that the outdoor landscape design provides more opportunities for different seasons to communicate with the atmosphere and so enhance thermal comfort and utilization.

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Efecto de la temperatura de bulbo seco y humedad relativa en la sensación térmica percibida en espacios exteriores en clima cálido seco

Revista de Invención Técnica ◽

10.35429/joti.2020.13.4.21.29 ◽

2020 ◽

pp. 21-29

Author(s):

Gonzalo Bojórquez-Morales ◽

Aníbal Luna-León ◽

Ramona Romero-Moreno ◽

Verónica Jiménez-López

Keyword(s):

Relative Humidity ◽

Thermal Comfort ◽

Thermal Environment ◽

Thermal Sensation ◽

Warm Period ◽

Cold Period ◽

Adaptation Level ◽

Activity Levels ◽

Critical Effect ◽

Outdoor Spaces

Conditions of the thermal environment in outdoor spaces determine not only its quality, but also the risk of morbidity from remaining in it. The objective of this research was to estimate the effect of dry bulb temperature and relative humidity on the perceived thermal sensation in outdoor spaces in hot dry climate. The thermal comfort adaptation approach was used with the thermal sensation interval means method, the analysis considered three activity levels for the warm period (with 823 observations) and cold period (with 863 observations), and the adaptation level of subjects based on their thermal sensation. The results indicate that even when the critical effect is due to the dry bulb temperature, the relative humidity has an important effect on the perceived sensation.

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A Pilot Test to Analyse the Differences of Pedestrian Thermal Comfort Between Locals and Internationals in Malacca Heritage Site

Environment and Urbanization Asia ◽

10.1177/0975425320946311 ◽

2020 ◽

Vol 11 (2) ◽

pp. 326-341

Author(s):

Golnoosh Manteghi ◽

Tasneem Mostofa ◽

Hasanuddin Bin Lamit

Keyword(s):

Thermal Comfort ◽

Thermal Environment ◽

Thermal Sensation ◽

Outdoor Thermal Comfort ◽

Pilot Test ◽

Physiological Equivalent Temperature ◽

Demographic Groups ◽

Human Thermal Comfort ◽

Heritage Site ◽

Outdoor Spaces

The present study aims to establish a correlation between the physiological equivalent temperature (PET) and subjective thermal sensation in the Tropics, assessing their impact on local as well as international pedestrians. The pilot test was conducted in six scenarios in the Malacca region of Malaysia. The RayMan model calculated the PET, which is further used to synthetically evaluate the thermal environment for six scenarios, each with a different river width and pavement material. The independent t-test and regression analysis determined the correlation between human thermal comfort acceptability and the thermal environment indices of outdoor spaces. Most of the outdoor thermal comfort assessments have been carried out focusing on local urban residents, while the same assessments on tourists are limited. This research provides necessary insight into the perception of outdoor microclimatic conditions in the Malacca heritage area and also identifies the perception on a few important psychological factors of these two demographic groups. An awareness of such issues would be fruitful for architects, planners and urban designers engaged in the process of designing and planning tourist destinations.

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A Review of Cultural Background and Thermal Perceptions in Urban Environments

Sustainability ◽

10.3390/su13169080 ◽

2021 ◽

Vol 13 (16) ◽

pp. 9080

Author(s):

Sanober Naheed ◽

Salman Shooshtarian

Keyword(s):

Thermal Comfort ◽

Thermal Environment ◽

Secondary Data ◽

Thermal Conditions ◽

Cultural Background ◽

Urban Environments ◽

Outdoor Thermal Comfort ◽

Complex Nature ◽

Physical Factors ◽

Outdoor Spaces

Thermal comfort is among the chief indicators of the sustainability of outdoor spaces. However, the complex nature of comfort represents the interaction of several determinants that leads to a perception of the thermal environment. Recently, researchers have paid particular attention to non-physical factors to understand the mechanisms involved in thermal perceptions in urban environments. The extant literature has contended that culture and cultural background are determinants to individuals’ thermal perceptions. Therefore, this study aimed to review how the link between outdoor thermal comfort (OTC) and cultural background is investigated. This is, to the best of our knowledge, the first review study on the subject. The study used a systematic literature review approach based on secondary data available in relevant and contemporary literature. The findings first showed the scarcity of research on cultural background and OTC; however, all studies identified corroborated the significant impact of cultural background on thermal perceptions. Notably, the cultural background was found to be the source of variation in thermal perceptions, tolerance to, and preference for certain thermal conditions, thermal comfort requirements and expectations, choice of clothing, and environmental attitudes. The findings provide a sound basis for future researchers to address the research gaps identified. The study also raises policy makers’ and designers’ awareness of urban environment users’ genuine needs and requirements.

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Evaluating the Connection between Thermal Comfort and Productivity in Buildings: A Systematic Literature Review

Buildings ◽

10.3390/buildings11060244 ◽

2021 ◽

Vol 11 (6) ◽

pp. 244

Author(s):

Ana Maria Bueno ◽

Antonio Augusto de Paula Xavier ◽

Evandro Eduardo Broday

Keyword(s):

Literature Review ◽

Thermal Comfort ◽

Systematic Literature Review ◽

Thermal Environment ◽

Final Analysis ◽

Personal Factors ◽

Exclusion Criteria ◽

Environment Variables ◽

Main Factors ◽

Combination Of Methods

The thermal environment is one of the main factors that influence thermal comfort and, consequently, the productivity of occupants inside buildings. Throughout the years, research has described the connection between thermal comfort and productivity. Mathematical models have been established in the attempt to predict changes in productivity according to thermal variations in the environment. Some of these models have failed for a number of reasons, including the understanding of the effect that several environment variables have had on performance. From this context, a systematic literature review was carried out with the aim of verifying the connection between thermal comfort and productivity and the combinations of different thermal and personal factors that can have an effect on productivity. A hundred and twenty-eight articles were found which show a connection between productivity and some thermal comfort variables. By means of specific inclusion and exclusion criteria, 60 articles were selected for a final analysis. The main conclusions found in this study were: (i) the vast majority of research uses subjective measures and/or a combination of methods to evaluate productivity; (ii) performance/productivity can be attained within an ampler temperature range; (iii) few studies present ways of calculating productivity.

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Development of a Deep Neural Network Model for Estimating Joint Location of Occupant Indoor Activities for Providing Thermal Comfort

Energies ◽

10.3390/en14030696 ◽

2021 ◽

Vol 14 (3) ◽

pp. 696

Author(s):

Eun Ji Choi ◽

Jin Woo Moon ◽

Ji-hoon Han ◽

Yongseok Yoo

Keyword(s):

Neural Network ◽

Thermal Comfort ◽

Deep Neural Network ◽

Mean Squared Error ◽

Thermal Environment ◽

The Body ◽

Estimation Accuracy ◽

Accurate Estimation ◽

Body Parts ◽

Joint Location

The type of occupant activities is a significantly important factor to determine indoor thermal comfort; thus, an accurate method to estimate occupant activity needs to be developed. The purpose of this study was to develop a deep neural network (DNN) model for estimating the joint location of diverse human activities, which will be used to provide a comfortable thermal environment. The DNN model was trained with images to estimate 14 joints of a person performing 10 common indoor activities. The DNN contained numerous shortcut connections for efficient training and had two stages of sequential and parallel layers for accurate joint localization. Estimation accuracy was quantified using the mean squared error (MSE) for the estimated joints and the percentage of correct parts (PCP) for the body parts. The results show that the joint MSEs for the head and neck were lowest, and the PCP was highest for the torso. The PCP for individual activities ranged from 0.71 to 0.92, while typing and standing in a relaxed manner were the activities with the highest PCP. Estimation accuracy was higher for relatively still activities and lower for activities involving wide-ranging arm or leg motion. This study thus highlights the potential for the accurate estimation of occupant indoor activities by proposing a novel DNN model. This approach holds significant promise for finding the actual type of occupant activities and for use in target indoor applications related to thermal comfort in buildings.

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How Can We Adapt Thermal Comfort for Disabled Patients? A Case Study of French Healthcare Buildings in Summer

Energies ◽

10.3390/en14154530 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4530

Author(s):

Youcef Bouzidi ◽

Zoubayre El Akili ◽

Antoine Gademer ◽

Nacef Tazi ◽

Adil Chahboun

Keyword(s):

Thermal Comfort ◽

Thermal Environment ◽

Residential Buildings ◽

Linear Regression Analysis ◽

Environmental Parameters ◽

Physical Parameters ◽

Mean Radiant Temperature ◽

Operative Temperature ◽

Neutral Temperature ◽

Radiant Temperature

This paper investigates adaptive thermal comfort during summer in medical residences that are located in the French city of Troyes and managed by the Association of Parents of Disabled Children (APEI). Thermal comfort in these buildings is evaluated using subjective measurements and objective physical parameters. The thermal sensations of respondents were determined by questionnaires, while thermal comfort was estimated using the predicted mean vote (PMV) model. Indoor environmental parameters (relative humidity, mean radiant temperature, air temperature, and air velocity) were measured using a thermal environment sensor during the summer period in July and August 2018. A good correlation was found between operative temperature, mean radiant temperature, and PMV. The neutral temperature was determined by linear regression analysis of the operative temperature and Fanger’s PMV model. The obtained neutral temperature is 23.7 °C. Based on the datasets and questionnaires, the adaptive coefficient α representing patients’ capacity to adapt to heat was found to be 1.261. A strong correlation was also observed between the sequential thermal index n(t) and the adaptive temperature. Finally, a new empirical model of adaptive temperature was developed using the data collected from a longitudinal survey in four residential buildings of APEI in summer, and the obtained adaptive temperature is 25.0 °C with upper and lower limits of 24.7 °C and 25.4 °C.

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