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The air quality in classrooms significantly impacts school children's health and learning performance. It has been reported worldwide that classroom air quality does not meet the required standard and actions are pledged for improvement. However, it poses a challenge for decision-making in terms of prioritising taking-up measures. The aim of this study is to propose a method of identifying the action measures for improving classroom air quality and prioritising them. Case studies in the UK and China were conducted, and the key measures were identified through literature studies, open-ended questionnaire surveys, and workshop discussions, which are classified into three categories: B1, policy; B2, technology; and B3, information sharing. The analytical hierarchy process (AHP) is applied in the prioritisation of the action measures. A total of 138 teachers and parents from China and the UK participated in this case study. The genetic algorithm-optimised Hadamard product (GAOHP) method is applied to justify the consistency ratio (CR) within the required threshold value in order to ensure the consistency of the subjective perception and the accuracy of comparative weights. The results show that item B2, technology, is the most desired measure by both Chinese and British parents and teachers, despite the deviation from the optimal choice in China and the UK. Among the proposed action measures, the UK respondents strongly expected air purifiers with natural ventilation as opposed to their Chinese counterparts preferring to share the real-time status of classroom air quality. Our work will provide strong support for the subsequent selection of indoor air quality improvement strategies for schools. [ABSTRACT FROM AUTHOR]

In this study, 12 cases were investigated in an office-layout room using experiments and computational fluid dynamics (CFD) simulations. The heating performances of four ventilation methods (i.e. mixing ventilation (MV), stratum ventilation (SV), deflection ventilation (DeV) and impinging jet ventilation (IJV)) were comprehensively compared by various evaluation indexes (i.e. predicted mean vote (PMV), draught rate (DR), vertical air temperature difference (△T), air diffusion performance index (ADPI), energy utilization coefficient (EUC), air change efficiency (ACE) and contaminant removal efficiency (CRE)). Better thermal comfort was found in rooms heated by SV and DeV. The PMV, DR and △T under SV and DeV complied with Category B of ISO 7730:2005, and the ADPI was in full compliance with the stipulation of ANSI/ASHRAE 113-2022. For the energy-saving characteristic, the targeted-occupied-zone ventilation methods (i.e. SV, DeV and IJV) can effectively deliver warm air to the occupied zone, with the EUC values higher than unity and thus providing a good potential for energy saving. SV and IJV showed slightly higher ACEs in the breathing zone. The contaminant removal effectiveness of SV, DeV and IJV was comparable. Under the combined influence of occupant thermal plumes and locations of exhausts, MV showed a high CRE. However, the CRE under MV decreased significantly when the exhausts were not above occupants. In the case of supply air parameters in this study, the entropy-weight method indicated that DeV and SV had a better overall performance for winter heating, followed by IJV and then MV. [ABSTRACT FROM AUTHOR]

Purpose: The Internet of Things has made the shift to the digital era possible, even though the Architecture, Engineering and Construction (AEC) sector has not embraced nor integrated it within the core functions compared to other sectors. The need to enhance sustainable construction with the adoption of Internet of Things in this sector cannot be overemphasized. However, the real-world applications of Internet of Things in smart buildings remain relatively unexplored in the AEC sector due to several issues related to deployment and energy-saving potentials. Given these challenges, this paper proposes to identify the present state of development and research in Internet of Things and smart buildings, identify Internet of Things clusters and applications in smart buildings. Design/methodology/approach: Bibliometric analyses of papers from 2010 to 2023 using the Scopus database and scientometric evaluations using the VosViewer software were undertaken. The proper search keyword was identified by using the phrases " Internet of Things" and "Smart Building". A total of 1158 documents in all, written by 3540 different writers, representing 2285 different institutions from 97 different countries were looked at. A metasynthesis was conducted and a system of Internet of Things applications in a smart building is illustrated. Findings: The development of IoT and Smart Buildings is done in two phases: initiation (2010–2012) and development phase (2013–2023). The IoT clusters comprised Internet of things, energy efficiency, intelligent buildings, smart buildings and automation; while the most commonly used applications were analysed and established. The study also determined the productive journals, documents, authors and countries. Research limitations/implications: Documents published in the Scopus database from 2010 to 2023 were considered for the bibliometric analysis. Journal articles, conference papers, reviews, books and book chapters written in English language represent the inclusion criteria, while articles in press, conference reviews, letters, editorials, undefined sources and all medical and health publications were excluded. Practical implications: The results of this study will be used by construction stakeholders and policymakers to identify key themes and applications in IoT-enabled smart buildings and to guide future research in the policymaking process of asset management. Originality/value: The study utilised bibliometric analysis, scientometrics and metasynthesis to investigate Internet of things applications in smart buildings. The study identified Internet of things clusters and applications for smart building design and construction. [ABSTRACT FROM AUTHOR]

The presence of dampness and visible molds leads to concerns of poor indoor air quality which has been consistently linked with increased exacerbation and development of allergy and respiratory diseases. Due to the limitations of epidemiological surveys, the actual fungal exposure characteristics in residences has not been sufficiently understood. This study aimed to characterize household fungal diversity and its annual temporal and spatial variations. We developed combined cross‐sectional survey, repeated air sampling around a year, and DNA sequencing methods. The questionnaire survey was conducted in 2019, and 4943 valid cases were received from parents; a follow‐up case–control study (11 cases and 12 controls) was designed, and onsite measurements of indoor environments were repeated in typical summer, transient season, and winter; dust from floor and beddings in children's room were collected and ITS based DNA sequencing of totally 68 samples was conducted. Results from 3361 children without changes to their residences since birth verified the significant associations of indoor dampness/mold indicators and prevalence of children‐reported diseases, with increased adjusted odd ratios (aORs) >1 for studied asthma, wheeze, allergic rhinitis, and eczema. The airborne fungal concentrations from air sampling were higher than 1000 CFU/m3 in summer, regardless of indoors and outdoors, indicating an intermediate pollution level. The DNA sequencing for dust showed the Aspergillus was the predominant at genus level and the Aspergillus_penicillioides was the most common at species level; while the fungal community and composition varied significantly in different homes and seasons, according to α and β diversity analyses. The comprehensive research methods contribute to a holistic understanding of indoor fungal exposure, including the concentrations, seasonal variations, community, and diversity, and verifies the relations with children's adverse health outcomes. The study further elucidates the role of microbiome in human health, which helps setting health‐protective thresholds and managing mold treatments in buildings, to promote indoor air quality and human well‐beings. [ABSTRACT FROM AUTHOR]

The philosophy of building 'lean' workplaces, to maximise occupant performance, has seen a stripping away of nature within built environments. However, the biophilia hypothesis indicates that a severance in human connection with nature can lead to significant reductions in health, well-being and performance. The aim of this study was to determine whether introducing and removing living plants within an office environment can affect occupants' perceived health, well-being and performance metrics. 40 occupants took part within a modern office building with 2 potted plants per person introduced into individual offices, and 8 in break-out spaces. Changes in occupants' perception were tested using questionnaires. Whether the location of planting impacted measured parameters and occupants' workplace satisfaction was also investigated. Introducing plants into offices had significantly positive effects on occupants' perceived attention, creativity and productivity; plants' removal elicited significantly negative effects in perceived attention, productivity, stress and efficiency. Planting had no significant effect on perceived health, tiredness, motivation or well-being. Furthermore, interactions with plants during break times had no significant effect on perceived performance metrics. This study showed occupants to have improved satisfaction with their overall workplace environment when they have physical and visual access to plants within their offices and break-out spaces. [ABSTRACT FROM AUTHOR]

In recent years, computational fluid dynamics (CFD) has been widely used as a method of simulating airflow and addressing indoor environment problems. The complexity of airflows within the indoor environment would make experimental investigation difficult to undertake and also imposes significant challenges on turbulence modelling for flow prediction. This research examines through CFD visualization how air is distributed within a room. Measurements of air temperature and air velocity have been performed at a number of points in an environmental test chamber with a human occupant. To complement the experimental results, CFD simulations were carried out and the results enabled detailed analysis and visualization of spatial distribution of airflow patterns and the effect of different parameters to be predicted. The results demonstrate the complexity of modelling human exhalation within a ventilated enclosure and shed some light into how to achieve more realistic predictions of the airflow within an occupied enclosure. [ABSTRACT FROM PUBLISHER]

Met Office station data from 1980 to 2012 has been used to characterise the interannual variability of incident solar irradiance across the UK. The same data are used to evaluate four popular historical irradiance products to determine which are most suitable for use by the UK PV industry for site selection and system design. The study confirmed previous findings that interannual variability is typically 3–6% and weighted average probability of a particular percentage deviation from the mean at an average site in the UK was calculated. This weighted average showed that fewer than 2% of site‐years could be expected to fall below 90% of the long‐term site mean. The historical irradiance products were compared against Met Office station data from the input years of each product. This investigation has found that all products perform well. No products have a strong spatial trend. Meteonorm 7 is most conservative (MBE = −2.5%), CMSAF is most optimistic (MBE = +3.4%) and an average of all four products performs better than any one individual product (MBE = 0.3%). [ABSTRACT FROM AUTHOR]