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To examine changes and socioeconomic patterns in indicators of a poor indoor environment in 2000 and 2021. Cross-sectional data from the Danish Health and Morbidity Survey in 2000 and 2021. The study included 27,068 participants. Indicators of indoor environment (annoyances from mould, temperature, draught, traffic and neighbour noise, and presence of water damage) were obtained from questionnaires (2021) and partly by interview (2000). Socioeconomic status included home ownership, educational level, and household income. The degree of social inequality in the indoor environment was estimated using the concentration index of inequality. The prevalence of annoyances due to draught, temperature, and noise increased significantly from 2000 to 2021 (e.g., temperature 5.9%–25.1%, odds ratio (OR) 6.72, 95% confidence interval (CI) 6.12–7.38), whereas the prevalence of water damage decreased (17.7%–13.8%, OR 0.85, 95% CI 0.76–0.96). No difference was seen in annoyances due to mould (3.1% in 2000 and 2.5% in 2021, OR 0.90, 95% CI 0.69–1.17). Social inequality was present for thermal conditions, annoyances due to noise and presence of water damage when assessed by income but not by educational level. Conditions were more prevalent among individuals with low income in both 2000 and 2021. The proportion of individuals reporting a poor indoor environment due to thermal conditions and noise increased in the period 2000–2021. Social inequality was observed in all indicators of a poor indoor environment for household income, whereas the inequality was less pronounced when assessed by educational level. [ABSTRACT FROM AUTHOR]

The Covid 19 pandemic has significantly affected the health, economy, and social impact of humanity. The continuous mutations of the virus variants have accelerated the demand for scientific research on disinfection techniques for a safer indoor environment. Among all the available surface disinfection techniques, ultraviolet germicidal irradiance at 254 nm wavelength has been proven for its disinfection efficacy; however, its usage is limited to unoccupied conditions due to the risk of ultraviolet exposure. This study investigated the efficacy of far-UVC-222 nm experimentally in both controlled environment and field setting. Staphylococcus epidermidis and Mycobacterium smegmatis were employed for surface disinfection in both the laboratory and a meeting room. Total plate count was used to determine the disinfection efficacy by a 20 W unfiltered far-UVC lamp. At 1.1 µW/cm2 far-UVC irradiation, a 1-log10 reduction of Staphylococcus epidermidis and Mycobacterium smegmatis contamination on tabletop can be achieved by 31.3 min and 101.8 min of far-UVC irradiation, respectively. Other pathogens of interest such as Staphylococcus aureus, Mycobacterium tuberculosis, Legionella pneumophila, SARS-CoV-2, and the Measles virus were also referred and compared in this study. This study carefully examined how far-UVC irradiation performs effectively for surface disinfection in a real meeting room setting. The results offer useful recommendations for alternatives to upper-room ultraviolet germicidal irradiance for continuous disinfection within the ultraviolet threshold limit value, with the goal of preventing the spread of any diseases in the future. [ABSTRACT FROM AUTHOR]

Office employees often face discomfort due to dry air, impacting their productivity. Existing solutions like standalone humidifiers or HVAC-integrated systems are either inefficient or costly. Thus, maintaining optimal air humidity remains a challenge. Green walls offer a potential solution by influencing humidity and air quality. A survey was conducted in five Warsaw office buildings involving 85 participants to investigate this issue. Measurements were taken in three stages: without humidifiers, with standalone humidifiers, and with green walls. The results showed a high acceptance of humidification systems, with green walls being perceived as the most effective in neutralizing air humidity perception. The air quality was rated highest with both humidifiers and green walls. Notably, well-being indicators significantly improved with humidifiers, particularly with the presence of green walls. This study underscores the potential of green walls in improving indoor environmental conditions and occupants' well-being, offering a promising avenue for enhancing office comfort and efficiency. [ABSTRACT FROM AUTHOR]

Purpose: Hoarseness and voice problems are one of the chronic conditions experienced by children. The aim of this study was to investigate the prevalence of hoarseness, possible risk factors and effects of the remediation of school buildings to the prevalence of hoarseness among school children. Methods: The material was gathered from all the schools in a large city in the south of Finland and the collection method used was an e-mail survey sent to the parents of the pupils and a simultaneous survey sent to the personnel in the schools. Results: All 51 schools participated, and 5889 pupils returned the questionnaire (39%). The exposure data was obtained from two building experts who knew the repair history of the schools. A subjective estimation of the quality of the indoor air was obtained from teachers and the parents. The overall prevalence of hoarseness among pupils was 6.3%; prevalence being higher in unrepaired school buildings than in schools in a good condition or buildings with a thorough remediation. Hoarseness was associated with asthma and allergies, several respiratory symptoms, and respiratory infections. Exposure to tobacco smoke increased the risk, and consumption of caffeine containing drinks seemed to reduce the risk. Noise, stuffiness of the indoor air and microbial smells correlated strongly with the occurrence of hoarseness in a logistic regression model when controlled for age, gender, asthma, passive smoking, and caffeine consumption. Conclusions: We recommend renovations in school buildings with the aim of providing better acoustics, sufficient ventilation, and a reduction in exposure to moisture damage microbes. [ABSTRACT FROM AUTHOR]

• The VOC emissions of leather with different grades and the health risk were studied. • The hexanal is the main cause of the unpleasant taste in low grade leathers. • The relationship between VOCs and health risk in sofa leathers were determined. • The leather materials barely pose health effects to residents. Furniture is identified as a vital volatile organic compound (VOC) emission source in the indoor environment. Leather has become the most common raw and auxiliary fabric material for upholstered furniture, particularly with extensive consumption in sofas, due to its abundant resources and efficient functions. Despite being widely traded across the world, little research has been conducted on the VOCs released by leather materials and their health risk assessment in the indoor environment. Accordingly, this study investigated the VOC emissions of leather with different grades and the health risk of the inhalation exposure. Based on the ultra-fast gas phase electronic nose (EN) and GC-FID/Qtof, the substantial emissions of aliphatic aldehyde ketones (Aks), particularly hexanal, appear to be the cause of off-flavor in medium and low grade (MG and LG) sofa leathers. The health risk assessment indicated that leather materials barely pose non-carcinogenic and carcinogenic effects to residents. Given the abundance of VOC sources and the accumulation of health risks in the indoor environment, more stringent specifications concerning qualitative and quantitative content should be extended to provide VOC treatment basic for the manufacturing industry and obtain better indoor air quality. [Display omitted] [ABSTRACT FROM AUTHOR]

Rising global temperatures can lead to heat waves, which in turn can pose health risks to the community. However, a notable gap remains in highlighting the primary contributing factors that amplify heat-health risk among vulnerable populations. This study aims to evaluate the precedence of heat stress contributing factors in urban and rural vulnerable populations living in hot and humid tropical regions. A comparative cross-sectional study was conducted, involving 108 respondents from urban and rural areas in Klang Valley, Malaysia, using a face-to-face interview and a validated questionnaire. Data was analyzed using the principal component analysis, categorizing factors into exposure, sensitivity, and adaptive capacity indicators. In urban areas, five principal components (PCs) explained 64.3% of variability, with primary factors being sensitivity (health morbidity, medicine intake, increased age), adaptive capacity (outdoor occupation type, lack of ceiling, longer residency duration), and exposure (lower ceiling height, increased building age). In rural, five PCs explained 71.5% of variability, with primary factors being exposure (lack of ceiling, high thermal conductivity roof material, increased building age, shorter residency duration), sensitivity (health morbidity, medicine intake, increased age), and adaptive capacity (female, non-smoking, higher BMI). The order of heat-health vulnerability indicators was sensitivity > adaptive capacity > exposure for urban areas, and exposure > sensitivity > adaptive capacity for rural areas. This study demonstrated a different pattern of leading contributors to heat stress between urban and rural vulnerable populations. [ABSTRACT FROM AUTHOR]

The available information on endotoxin in Chinese households is limited and there is inconsistency regarding its impact on asthma and allergies in children. A case-control study was performed in 324 homes in Tianjin, China. Linear regression analysis was performed to identify the determinants of endotoxin concentrations in household dust. Logistic regression models were employed to investigate the associations of endotoxin concentrations with asthma and allergies in children. Endotoxin concentrations were determined from 284 valid dust samples, ranging from 94 to 11,625 EU/g, with a mean concentration of 3638 EU/g. We found a significant positive association between endotoxin concentrations and children's current asthma. Old houses, ventilation systems without exhaust fans and windows opened infrequently were related to higher concentrations of endotoxins. In conclusion, endotoxin exposure in the home might be a risk factor for current asthma in children. Strategies for controlling endotoxin concentrations such as building maintenance and ventilation improvements are recommended. [ABSTRACT FROM AUTHOR]

Massive cultural objects made of wood are often situated in historic interiors in which they experience uncontrolled dynamic variations of relative humidity (RH). Although the objects usually have acclimatized to the natural climate variability, preventing risks related to any kind of modification of their environment requires an understanding of the object's response to the expected changes. In the present study, an analysis of the risk of cracking related to continuous or intermittent heating, or the transfer to hypothetically ideal conditions in a conservation studio was performed for the case of elements of Veit Stoss' altarpiece (1477–1489) preserved in St. Mary's Basilica in Krakow, Poland. Massive sculptures carved in lime wood and approximately one meter in diameter were analysed. The study aimed at determining safe margins of environment modifications that would not cause propagation of cracks that are known to have accumulated in wood during centuries of the altarpiece's existence. The mechanical properties of lime wood were determined experimentally to feed the numerical model. The energy release rates around the tips of cracks of various depths in a wooden sculpture were calculated using the finite element analysis and compared with the critical value of the parameter triggering the fracture propagation in the material, derived from the fracture energy measurement. It was shown that the church interior housing the altarpiece can be heated to 11 °C during the cold season to provide human comfort. The allowable duration of intermittent heating events to more comfortable 18 °C that would induce drops in RH of up to 40% was assessed as 12 h. The study demonstrated that moving the sculptures to the conservation studio would have to be done with extreme caution as it would be connected with risks depending on the depth of existing cracks and the duration of the RH change. [ABSTRACT FROM AUTHOR]

Developing mmWave radar sensors for indoor crowd motion sensing and tracking faces a critical challenge: the scarcity of large-scale, high-quality training data. Traditional human experiments encounter logistical complexities, ethical considerations, and safety issues. Replicating precise human movements across trials introduces noise and inconsistency into the data. To address this, this study proposes a novel solution: a movable platform equipped with a life-size mannequin to generate realistic and diverse data points for mmWave radar training and testing. Unlike human subjects, the platform allows precise control over movements, optimising sensor placement relative to the target object. Preliminary optimisation results reveal that sensor height impacts tracking performance, with an optimal sensor placement above the test subject yields the best results. The results also reveal that the 3D data format outperforms 2D data in accuracy despite having fewer frames. Additionally, analysing height distribution using 3D data highlights the importance of the sensor angle—15° downwards from the horizontal plane. [ABSTRACT FROM AUTHOR]

With the rapid development of wireless communication systems, particularly in the era of 5G and the Internet of Things, deploying wireless communication networks in indoor environments has become crucial. Indoor infrastructure deployment necessitates innovative approaches for efficiently and accurately obtaining received signal strength (RSS) maps. However, traditional methods for acquiring RSS maps, such as empirical and deterministic models, are limited by significant inaccuracies and high computational demands. Empirical models often fail to capture the complex dynamics of indoor environments, resulting in deviations from actual signal behaviours. On the other hand, deterministic models, while more accurate, are computationally intensive due to their reliance on detailed physical modelling of wave propagation. This study introduces a machine learning approach based on deep convolutional generative adversarial networks (DCGAN) aimed at reconstructing indoor RSS maps with minimal RSS measurements. By leveraging DCGAN's generative and adversarial training capabilities, the method not only surpasses traditional interpolation methods in efficiency and precision but also offers new possibilities for the rapid deployment and optimization of wireless communication systems in indoor environments. [ABSTRACT FROM AUTHOR]

The aim of the article is to analyze the perceived thermal comfort and indoor air quality of occupants and establish associations between these responses and the building-related, occupant-related characteristics, and environmental parameters of residential buildings (a total of 38 variables). The analysis is focused on the Swedish building stock as investigated during the latest national survey in 2008. The analysis covers 1035 residential buildings (multifamily and single-family dwellings). Analytical statistical analysis has been conducted, and logistic regression models have also been developed for the identification of statistically significant covariates. The analysis showed that users in this study demonstrated a significantly positive response to perceived thermal comfort and indoor air quality conditions. Perceived ratings were also highly correlated with each other. As the regression models indicated, the majority of the significant variables were related to the buildings. Nevertheless, this study also underscores the significance of contextual occupant attributes and behaviors as a crucial element influencing the subjective perception of indoor environments. Policymakers, guided by these insights, are encouraged to integrate considerations of occupant attributes into design and urban planning. [ABSTRACT FROM AUTHOR]

This paper experimentally analyses an indoor environment assessment of a large group of respondents regarding their subjective perception of overall comfort, indoor air quality and humidity. The questionnaire survey was applied as a testing method together with measurements of the physical parameters conducted with a microclimate meter. Two types of environment were analysed: educational rooms and the climate chamber. The comparative analysis of the sensations experienced within them indicates that they generate quite similar responses; however, some discrepancies have been identified. The overall comfort of the climate chamber was typically assessed as being higher than that of the educational rooms at the same air temperature. The most favourable air temperature in the climate chamber was ca. 20.7 °C, while in the educational rooms it was ca. 22.3 °C. The most preferable conditions in the climate chamber occurred at a thermal sensation vote of −0.4 ("pleasantly slightly cool"), while in the educational rooms it occurred at +0.2 ("neutral/pleasantly slightly warm"). Quite strong correlations between overall comfort and indoor air quality as well as between humidity assessment and humidity preference votes were observed, which did not seem to depend on the type of environment. These findings are important because results from the simulated conditions are often used in the analyses of actual living/working environments. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method for extracting the structure of an indoor environment using radar. When using the radar in an indoor environment, ghost targets are observed through the multipath propagation of radio waves. The presence of these ghost targets obstructs accurate mapping in the indoor environment, consequently hindering the extraction of the indoor environment. Therefore, we propose a deep learning-based method that uses image-to-image translation to extract the structure of the indoor environment by removing ghost targets from the indoor environment map. In this paper, the proposed method employs a conditional generative adversarial network (CGAN), which includes a U-Net-based generator and a patch-generative adversarial network-based discriminator. By repeating the process of determining whether the structure of the generated indoor environment is real or fake, CGAN ultimately returns a structure similar to the real environment. First, we generate a map of the indoor environment using radar, which includes ghost targets. Next, the structure of the indoor environment is extracted from the map using the proposed method. Then, we compare the proposed method, which is based on the structural similarity index and structural content, with the k-nearest neighbors algorithm, Hough transform, and density-based spatial clustering of applications with noise-based environment extraction method. When comparing the methods, our proposed method offers the advantage of extracting a more accurate environment without requiring parameter adjustments, even when the environment is changed. [ABSTRACT FROM AUTHOR]

To investigate the correlation between indoor environment and personnel learning performance, a typical classroom in a university in Xi'an was selected and continuously monitored for parameters such as indoor temperature and humidity, CO2 concentration, sound level and illumination, and 248 students were subjectively surveyed and field tested for learning efficiency using subjective questionnaires and neurobehavioural ability assessment software. The results show that during the transition season, students as a whole were in a cold but comfortable temperature range, with peak learning performance at 21.5 °C; Two-thirds of students feel comfortable in environments with CO2 concentration below 1 000 mg/m³ and the mean learning performance remained at a high level; Students preferred quiet environments but noise at 60 dB levels had an arousing effect on subjects; Brighter environments were more suitable for learning, but brighter than 340 lx could irritate the eyes and make students feel fatigued, resulting in lower learning efficiency; there were differences in the strength of correlations between environmental parameters and the four learning efficiency factors:concentration, perception, logic and memory, with concentration having a strong correlation with all four environmental parameters. [ABSTRACT FROM AUTHOR]

Siek building syndrome (SBS) is eharaeterized by a group of eommon symptoms that oeeur inside the building like working offiees, sehools, malls or industries. It eauses many adverse health effeets due to tightly paeked indoor environment. This is the first study done at the historieal plaee of Karaehi pertaining to SBS. A questionnaire based survey was eondueted in Empress market, Karaehi in Oetober 2018to find outthe negative impaet on human health as well as to give awareness about SBS to workers. This building eonsists of almost 280 shops and workers. The workers suffer from eommon health diseases like headaehe, fatigue and dryness of the throat. Congested areas, no ventilation, poor design and heavy traffie were observed. Fans were the only souree of ventilation. SBS effeets ean be redueed by the good ventilation souree, proper eleaning system, building maintenanee and proper bimonthly eheekup of the workers. [ABSTRACT FROM AUTHOR]

This work is proposed to evaluate the use of phytoremediation as a technique to eliminate the particulate matter lower than 10 and 2,5 µm (PM10 y PM2,5, respectively) present in indoor environments due to the associated adverse effects related to the public health damage and the population performance reduction at work level. For this purpose, arrangements made up of 6 ornamental plants readily available were used, such as the green miami (Epipremnum aureum), the aloe (Aloe vera), the peace flower (Spathiphyllum sp.), the curly fern (Nephrolepis exaltata), the syngonium (Syngonium podophyllum) and mother-in-law's tongue (Sansevieria trifasciata); which were installed in different dependencies of a higher education institution, where the level of PM2,5 and PM10 was previously determined. Once the arrangements were implemented, these measurements were averaged and compared with the data recorded to estimate their PM2,5 and PM10 removal percentage. In general, the positive effect associated with the implementation of the selected ornamental arrangements was evidenced, especially that one constituted by 2 individuals of Nephrolepis exaltata, in comparison with the dependencies used as a control. Therefore, phytoremediation may be considered as a solution to the environmental problem related to indoor air quality. [ABSTRACT FROM AUTHOR]

The existing monocular depth estimation methods based on deep learning have difficulty in estimating the depth near the edges of the objects in an image when the depth distance between these objects changes abruptly and decline in accuracy when an image has more noises. Furthermore, these methods consume more hardware resources because they have huge network parameters. To solve these problems, this paper proposes a depth estimation method based on weighted fusion and point‐wise convolution. The authors design a maximum‐average adaptive pooling weighted fusion module (MAWF) that fuses global features and local features and a continuous point‐wise convolution module for processing the fused features derived from the (MAWF) module. The two modules work closely together for three times to perform weighted fusion and point‐wise convolution of features of multi‐scale from the encoder output, which can better decode the depth information of a scene. Experimental results show that our method achieves state‐of‐the‐art performance on the KITTI dataset with δ1 up to 0.996 and the root mean square error metric down to 8% and has demonstrated the strong generalisation and robustness. [ABSTRACT FROM AUTHOR]

Background: Microplastics are persistent environmental pollutants. Their presence in water resources, air and food chains is a growing concern all over the world. Since air is a strong environmental substrate, the release and effects of airborne microplastics can remain localized or go far beyond the point of release. In this study, the indoor and outdoor air pollution of residential houses in Kermanshah, Iran, was investigated. Materials and Methods: In order to collect samples, different parts of the houses, including bedroom, living room, kitchen, corridor, yard and roof, were selected as the sampling points. Ten stations were selected as the sampling points. After washing with distilled water, the samples were transferred to the laboratory through a fiberglass filter (diameter 47 mm, 1.1 μm pore size) and filtered using a vacuum pump. After preparing and extracting the above samples, the visual method was used for the quantitative and qualitative detection of the microplastics. Results: The results of the study confirmed the presence of microplastics in all the samples. The frequency of microplastics was minimum 158 and maximum 4480 per square meter. The indoor samples were significantly more polluted than the outdoor samples. The highest frequency was related to black fiber, which can be attributed to a textile origin. Also, more than 78% of the samples were determined to be less than 500 micrometers in size. Conclusion: Exposure to microplastic-contaminated air is inevitable, and currently, our knowledge about the release of microplastics in indoor air as well as the factors affecting microplastic transmission is lacking. There is a need for more studies focusing on these issues, because they are of great importance in assessing the potential risk of microplastics on human health. [ABSTRACT FROM AUTHOR]

Room usage semantics in models of large indoor environments such as public buildings and business complex are critical in many practical applications, such as health and safety regulations, compliance, and emergency response. Existing models such as IndoorGML have very limited semantic information at room level, and it remains difficult to capture semantic knowledge of rooms in an efficient way. In this paper, we formulate the task of generating rooms usage semantics as a special case of room classification problems. Although methods for room classification tasks have been developed in the field of social robotics studies and indoor maps, they do not deal with room usage and occupancy aspects of semantics, and they ignore the value of furniture objects in understanding room usage. We propose a method for generating room usage semantics based on the spatial configuration of room objects (e.g., furniture, walls, windows, doors). This method uses deep learning architecture to support a room usage classifier that can learn spatial configuration features directly from semantically labelled point cloud (SLPC) data that represent room scenes with furniture objects in place. We experimentally assessed the capacity of our method in classifying rooms in office buildings using the Stanford 3D (S3DIS) dataset. The results showed that our method was able to achieve an overall accuracy of 91% on top-level room categories (e.g., offices, conference rooms, lounges, storage) and above 97% accuracy in recognizing offices and conference rooms. We further show that our classifier can distinguish fine-grained categories of of offices and conference rooms such as shared offices, single-occupancy offices, large conference rooms, and small conference rooms, with comparable intelligence to human coders. In general, our method performs better on rooms with a richer variety of objects than on rooms with few or no furniture objects. [ABSTRACT FROM AUTHOR]

Rammed-earth dwellings have a long history in the construction field. It is a natural material that is both green and environmentally friendly. In recent years, the advantages of rammed earth, such as environmental protection, low cost, and recyclability, have attracted considerable attention. In this study, the thermal and humidity physical properties of rammed–earth materials in the northwest Sichuan region, the variation laws of thermal physical parameters, such as the thermal conductivity of rammed–earth under different moisture content conditions, and isothermal moisture absorption and desorption curves were investigated. The results indicated that the thermal physical parameters of the rammed earth measured in the experiment increased with an increase in moisture content, and its moisture absorption performance was better than the moisture release performance in the range of 11.31–97.3% relative humidity. The experimental site, Mianyang City, Sichuan Province, is a subtropical monsoon humid climate zone characterized by warm winters and hot summers with four distinct seasons. In this study, we investigated the hygrothermal coupling transfer of walls, as well as the indoor temperature and humidity changes in new rammed–earth buildings during summer and winter climates. During the test period, the maximum indoor temperature in summer was 35.08 °C, the minimum temperature was 33.76 °C, and the average daily temperature fluctuation was 3.62 °C. In winter, the maximum indoor temperature was 8.59 °C, the minimum temperature was 6.18 °C, and the average daily temperature fluctuation was 1.21 °C. An analysis was performed on the thermal insulation performance of rammed–earth buildings in an extremely high-temperature climate during summer, thermal insulation performance, the thermal–buffering capacity of walls in a low–temperature and high-humidity climate during winter, and thermal and humidity regulation of indoor environments provided by walls during summer and winter. The results showed that the rammed–earth buildings exhibited warmth in winter, coolness in summer, and a more stable and comfortable indoor environment. [ABSTRACT FROM AUTHOR]

The comprehensive and accurate assessment of the indoor air quality (IAQ) in large spaces, such as offices or multipurpose facilities, is essential for IAQ management. It is widely recognized that various IAQ factors affect the well-being, health, and productivity of indoor occupants. In indoor environments, it is important to assess the IAQ in places where it is difficult to install sensors due to space constraints. Spatial interpolation is a technique that uses sample values of known points to predict the values of other unknown points. Unlike in outdoor environments, spatial interpolation is difficult in large indoor spaces due to various constraints, such as being separated into rooms by walls or having facilities such as air conditioners or heaters installed. Therefore, it is necessary to identify independent or related regions in indoor spaces and to utilize them for spatial interpolation. In this paper, we propose a spatial interpolation technique that groups points with similar characteristics in indoor spaces and utilizes the characteristics of these groups for spatial interpolation. We integrated the IAQ data collected from multiple locations within an office space and subsequently conducted a comparative experiment to assess the accuracy of our proposed method in comparison to commonly used approaches, such as inverse distance weighting (IDW), kriging, natural neighbor interpolation, and the radial basis function (RBF). Additionally, we performed experiments using the publicly available Intel Lab dataset. The experimental results demonstrate that our proposed scheme outperformed the existing methods. The experimental results show that the proposed method was able to obtain better predictions by reflecting the characteristics of regions with similar characteristics within the indoor space. [ABSTRACT FROM AUTHOR]

Background: Indoor dust particles are an everyday source of human exposure to microorganisms and their inhalation may directly affect the microbiota of the respiratory tract. We aimed to characterize the changes in human nasopharyngeal bacteriome after short-term exposure to indoor (workplace) environments. Methods: In this pilot study, nasopharyngeal swabs were taken from 22 participants in the morning and after 8 h of their presence at the workplace. At the same time points, indoor dust samples were collected from the participants' households (16 from flats and 6 from houses) and workplaces (8 from a maternity hospital – NEO, 6 from a pediatric hospital – ENT, and 8 from a research center – RCX). 16S rRNA sequencing analysis was performed on these human and environmental matrices. Results: Staphylococcus and Corynebacterium were the most abundant genera in both indoor dust and nasopharyngeal samples. The analysis indicated lower bacterial diversity in indoor dust samples from flats compared to houses, NEO, ENT, and RCX (p < 0.05). Participants working in the NEO had the highest nasopharyngeal bacterial diversity of all groups (p < 0.05). After 8 h of exposure to the workplace environment, enrichment of the nasopharynx with several new bacterial genera present in the indoor dust was observed in 76% of study participants; however, no significant changes were observed at the level of the nasopharyngeal bacterial diversity (p > 0.05, Shannon index). These "enriching" bacterial genera overlapped between the hospital workplaces – NEO and ENT but differed from those in the research center – RCX. Conclusions: The results suggest that although the composition of nasopharyngeal bacteriome is relatively stable during the day. Short-term exposure to the indoor environment can result in the enrichment of the nasopharynx with bacterial DNA from indoor dust; the bacterial composition, however, varies by the indoor workplace environment. [ABSTRACT FROM AUTHOR]

Mycological cleanliness of rooms directly translates into the health of their users. This is important for athletes who are actively training. The aim of the study was to evaluate the sanitary and epidemiological status of sports changing rooms by determining the species diversity of their mycobiota in the context of prevention of athletes' health. The research was carried out in changing rooms of sports halls used by volleyball players in the city of Olsztyn (NE Poland). Standard mycological isolation and identification methods were used in this study. A total of 87 strains of microfungi were isolated. 52 belonged to the mold fungi, among which 18 species, belonging to 10 were found. The species isolated most frequently were: Aspergillus fumigatus, A. niger, Juxtiphoma eupyrena (previous name: Phoma eupyrena) and Westerdykella minutispora (previous name: Ph. minutispora). 35 yeast strains, belonging to 15 species and 10 genera were isolated. The most common species were: Candida glabrata, C. krusei, C. parapsilosis and Rhodotorula glutinis. 5 species were categorized as class BSL-2 fungi. The conducted research justify the need for preventive examinations of athletes and shows the necessity of constant monitoring of the sanitary condition of the sport changing rooms. [ABSTRACT FROM AUTHOR]

Background: In Korea, winter can cause skin dryness due to low relative humidity (RH); moreover, indoor heating devices promote moisture loss and air pollution. If dryness persists, dead skin cells accumulate, leading to skin problems; therefore, careful skin care is required. This study aimed to compare changes in skin conditions when exposed to an indoor environment for a short period of 6 h in winter, and to suggest proper winter skin care practices. Methods: A randomized, split‐face clinical study was conducted in which healthy female participants with normal skin were exposed to an indoor environment with a heater turned on for a short period at least 6 h per day in the winter season, and cream was applied to one side of the face. Skin temperature, hydration, sebum, transepidermal water loss (TEWL), elasticity, texture, pores, redness, and wrinkles were measured at the treated and nontreated sites. Results: After 6 h of exposure, skin temperature, pores, roughness, redness, and wrinkles significantly increased (p < 0.05) on the face, whereas TEWL significantly increased on the forearm (p < 0.05). However, sebum secretion appeared to function as a barrier to maintain homeostasis in the facial skin. Elasticity, pores, texture, and wrinkles in the cream‐treated ceramide site improved compared to those in the nontreated site (p < 0.05). The moisture content was also significantly higher in the forearm (p < 0.05). Conclusion: Changes in skin parameters of participants with healthy skin were observed even after short‐term exposure to an indoor environment in winter. Creams containing ceramide maintain skin homeostasis and protect the skin barrier; therefore, it is recommended to use such creams to prevent skin damage and maintain healthy skin, particularly during prolonged exposure to indoor environments during winter. [ABSTRACT FROM AUTHOR]

When performing indoor tasks, miniature swarm robots are suffered from their small size, poor on-board computing power, and electromagnetic shielding of buildings, which means that some traditional localization methods, such as global positioning system (GPS), simultaneous localization and mapping (SLAM), and ultra-wideband (UWB), cannot be employed. In this paper, a minimalist indoor self-localization approach for swarm robots is proposed based on active optical beacons. A robotic navigator is introduced into a swarm of robots to provide locally localization services by actively projecting a customized optical beacon on the indoor ceiling, which contains the origin and the reference direction of localization coordinates. The swarm robots observe the optical beacon on the ceiling via a bottom-up-view monocular camera, and extract the beacon information on-board to localize their positions and headings. The uniqueness of this strategy is that it uses the flat, smooth, and well-reflective ceiling in the indoor environment as a ubiquitous plane for displaying the optical beacon; meanwhile, the bottom-up view of swarm robots is not easily blocked. Real robotic experiments are conducted to validate and analyze the localization performance of the proposed minimalist self-localization approach. The results show that our approach is feasible and effective, and can meet the needs of swarm robots to coordinate their motion. Specifically, for the stationary robots, the average position error and heading error are 2.41 cm and 1.44°; when the robots are moving, the average position error and heading error are less than 2.40 cm and 2.66°. [ABSTRACT FROM AUTHOR]

Aims: The aim of the study was to describe child health in relation to housing renovations in more than 800 rental units, consisting of repairs of dilapidated kitchens and bathrooms, in the disadvantaged neighbourhood of Herrgården in Rosengård, Malmö, Sweden. Methods: Data on housing conditions and self-reported health were collected during home visits to families living in Herrgården (building renovations area) and a comparison area (neighbouring Törnrosen, with generally better housing conditions). At baseline, 130 families with 359 children participated, while 51 families with 127 children participated at follow-up. All data were collected between 2010 and 2012. Additionally, regional register data on health-care usage/in- and outpatient contacts within the public health-care system between 2008 and 2013 were also collected for all 8715 children registered as living in the two areas. Results: Self-reported health seemed to somewhat improve in both areas, with 74% versus 86% and 78% versus 88% reporting good or very good health in Herrgården and in the comparison area at baseline and follow-up, respectively. In Herrgården, crowdedness increased, while it decreased in the comparison area. The number of health-care contacts remained stable over time in Herrgården, while it decreased in the comparison area. Conclusions: Partial housing renovations did not seem to result in clear health improvements as measured with the indicators used in the present study. This could possibly be due to persisting health effects due to increased crowdedness or persisting poor housing conditions, as only kitchens and bathrooms were renovated. [ABSTRACT FROM AUTHOR]

Solar chimney (SC) is one of the important means of indoor natural ventilation driven by thermal pressure. It is of great significance to improve the utilization rate of solar energy and ventilation performance. An external solar thermoelectric chimney was proposed based on the concept of strengthening chimney ventilation with discrete heat sources, and the ventilation characteristics of the chimney and its influence on indoor environment were discussed. Firstly, based on flow heat transfer mechanism and the theory of thermoelectric energy conversion, a two-dimensional unsteady model of solar thermoelectric chimney model was established. Secondly, the location of different thermoelectric elements, such as TEG-outlet, TEG-mid, TEG-inlet, ventilation performance and indoor environment flow distribution were analyzed, and the performance of thermoelectric power generation was further discussed. Finally, the differences of ventilation and power generation between external discrete thermoelectric chimney (TEG-SC) and traditional chimney ( SC) were compared to clarify the advantages of TEG-SC. The results show that with the increase of solar intensity, the outlet velocity and ACH of TEG-inlet are the largest compared with TEG-outlet and TEG-mid. At this time, the generation power of TEG at each location has little difference, but with the increase of solar intensity, the generation power of TEG-outlet will gradually increase. At the same time, the outlet velocity of TEG-SC is higher than that of a single TEG, and the total generation power is increased by nearly 3 times. Moreover, the ventilated volume of TEG-SC is increased compared with that of traditional SC, and the velocity is increased by 18. 5% on average. The external solar thermoelectric chimney system proposed in this paper will provide a solid theoretical basis and technical guidance for strengthening indoor natural ventilation and improving the utilization rate of solar energy. [ABSTRACT FROM AUTHOR]

The recent Coronavirus Disease 2019 pandemic has highlighted the importance of indoor ventilation. In particular, ventilation is crucial in residential spaces and workspaces, where people spent most of their day. Natural ventilation is a cost-effective method for improving indoor ventilation. It can provide safe and comfortable residential and working environments without additional energy consumption. In this study, the ventilation performance was experimentally studied by measuring the concentration of ultrafine particulate matter according to the opening conditions of the windows and door of an office model in a wind tunnel. Furthermore, the internal flow structure in the office model was quantitatively analyzed through particle image velocimetry to determine the factors that affected the ventilation performance. The mean velocity inside the model and the ventilation performance increased with the opening angle of the windows. In particular, the opening condition of the door strongly affected the ventilation performance. This study is expected to provide a guideline for effectively improving the ventilation performance in indoor spaces. [ABSTRACT FROM AUTHOR]

Air curtains are frequently used as separation barriers to reduce the transfer of dust, heat, and smoke between two areas. When people travel from one location to another, they bring dust and airflow with them, known as slipstream. To limit the spread of toxins inside any indoor environment, it is critical to understand the human-induced slipstream. The usefulness of air curtains in preventing human-induced slipstream movement is investigated in this study. We also used an air curtain to monitor airflow, dust flow, and particulate matter transfer from a contaminated zone to a cleaner zone in the chamber. A dust sensor and a particulate matter sensor were used to assess real-time monitoring of dust and PM 2.5,10 particles created, as well as the human-induced slipstream. The experiment was performed at a different position (horizontal, vertical, wedge) of the air curtain unit (ACU) and different vane angles (10°−15°, 15°−30°, 30°−45°) with the human walking and without as well. The maximum efficiency for horizontal was 47% at 30°− 45°, for wedge position, it was 74% at 15°− 30°, and for the vertical, it was 81.4% at 30°− 45° angles. Maximum efficiency was found at 81.4% with vertical direction at 30°− 45°. This can help to achieve maximum PM reduction in commercial and public offices. [ABSTRACT FROM AUTHOR]

We present an open-source wireless network and data management system for collecting and storing indoor environmental measurements and perceived comfort via participatory sensing in commercial buildings. The system, called a personal comfort and indoor environment measurement (PCIEM) platform, consists of several devices placed in office occupants' work areas, a wireless network, and a remote database to store the data. Each device, called a PCFN (personal comfort feedback node), contains a touchscreen through which the occupant can provide feedback on their perceived comfort on-demand, and several sensors to collect environmental data. The platform is designed to be part of an indoor climate control system that can enable personalized comfort control in real-time. We describe the design, prototyping, and initial deployment of a small number of PCFNs in a commercial building. We also provide lessons learned from these steps. Application of the data collected from the PCFNs for modeling and real-time control will be reported in future work. We use hardware components that are commercial and off-the-shelf, and our software design is based on open-source tools that are freely and publicly available to enable repeatability. [ABSTRACT FROM AUTHOR]

High-rise urban development has been controversial for its inability to foster cohesive and flourishing neighbourhoods. A social value perspective can help to better understand and evaluate how new developments in dense urban settings affect places and communities. While the link between wellbeing and social value is well-established in the literature, the question of how design can affect wellbeing and thus contribute to the social value of a development still requires further research and clarification. A better understanding of this relationship can assist architects, developers or consultants during the design process. A review is presented of relevant quantifiable aspects of building design that affect wellbeing in relation to the indoor environment and to social value specifically. A framework for fostering wellbeing is developed to test these aspects and evaluate the indoor environment performance. A case study building is used to analyse the relationship between building design and wellbeing. These lessons can be used to inform and evaluate building design during the design phases to complement the assessment of qualitative factors within a social value framework. [ABSTRACT FROM AUTHOR]

Housing quality is essential for population health and broader well-being. The World Health Organization Housing and health guidelines highlight interventions that protect occupants from cold and hot temperatures, injuries, and other hazards. The COVID-19 pandemic has emphasized the importance of ventilation standards. Housing standards are unevenly developed, implemented, and monitored globally, despite robust research demonstrating that retrofitting existing houses and constructing high-quality new ones can reduce respiratory, cardiovascular, and infectious diseases. Indigenous peoples, ethnic minorities, and people with low incomes face cumulative disadvantages that are exacerbated by poor-quality housing. These can be partially ameliorated by community-based programs to improve housing quality, particularly for children and older people, who are hospitalized more often for housing-related illnesses. There is renewed interest among policy makers and researchers in the health and well-being of people in public and subsidized housing, who are disproportionately disadvantaged by avoidable housing-related diseases and injuries. Improving the overall quality of new and existing housing and neighborhoods has multiple cobenefits, including reducing carbon emissions. [ABSTRACT FROM AUTHOR]

This study emphasizes the critical role of air conditioning (AC) in preventing heat-related illnesses such as heat exhaustion and heatstroke. The challenge of limited geographic coverage and outdated AC availability data hampers effective heat risk mapping and prevention efforts. We identified areas with significant AC needs and examined factors related to AC ownership in Florida, U.S. Local Indicators of Spatial Association results displayed distinct AC ownership disparities, with high-high clusters in coastal and metropolitan areas and AC-deficient clusters inland. Vulnerable urban communities, predominantly inhabited by marginalized groups, had limited to no AC availability. The Spatial Durbin Model results revealed a significant correlation between AC ownership and socioeconomic and urban factors. Notably, a higher proportion of AC-deficient households were in predominantly African-American neighborhoods, underscoring racial disparities in AC ownership. These findings provide valuable insights for targeted interventions to mitigate heat-related risks and adapt to evolving climate conditions in vulnerable neighborhoods. [ABSTRACT FROM AUTHOR]

Modeling radon (222Rn) development in confined environments aids in predicting radon levels in dwellings and underground spaces, where radium 226Ra in building materials and soil emits radon gas via radioactive decay. Radon accumulates in poorly ventilated places, creating an inhalation hazard. In OpenFOAM, a C+ +-based computational tool, an existing heat conduction solver was adapted to simulate radon accumulation, considering radon's radioactive characteristics and material non-uniformity through which radon will permeate. The solver was validated against theoretical values in a one-dimensional system and then applied to study radon dispersion in containment, with potential for broader applications. [ABSTRACT FROM AUTHOR]

This study introduces an advanced method for reconstructing pollutant concentration fields in indoor ventilated environments, aimed at enhancing air quality and ensuring occupant health. Our newly developed Kernel DM + V/W+ method significantly refines existing models by accurately capturing variations in pollutant dispersion in downwind areas while minimizing overestimations in upwind zones. This innovative approach overcomes the limitations of the traditional Kernel DM + V method, which neglects the impact of airflow, and the Kernel DM + V/W method, which inadequately differentiates between upwind and downwind dispersion. The effectiveness of this method is validated through a dataset derived from previously confirmed computational fluid dynamics (CFD) simulations across two standard indoor ventilation scenarios. A subset of this dataset was randomly selected for evaluation using the three methods, enabling a detailed performance analysis. The results demonstrate that the Kernel DM + V/W+ method markedly enhances accuracy in estimating concentrations at unsampled locations and significantly improves the identification of pollution sources, providing substantial benefits for environmental engineering applications. [Display omitted] • Enhanced method for accurate indoor pollution mapping. • Differentiated airflow effects in upwind and downwind areas. • Improved pollutant visualization with fewer data points. • Better performance in locating pollution sources. • Applicable to environmental monitoring and health protection. [ABSTRACT FROM AUTHOR]

Contaminated hands of people and contaminated surfaces of inanimate objects (fomites) can spread microbes that cause enteric and respiratory infections. Thus, hand hygiene and surface hygiene are probably the most widely adopted public health interventions for controlling such infections. However, conclusions of studies on the effectiveness of these interventions are often inconsistent, likely because such studies have examined these interventions separately and thus not detected their interactions, leading to differing conclusions about their individual impact. In this study, it is proposed that hand and environmental surface hygiene (including disinfection) should be coupled to control contamination spread between surfaces, especially within heterogeneous surface touch networks. In these networks, surfaces and individuals have varying contact frequencies and patterns, reflecting the diverse and non-uniform interactions that typically occur in real-world environments. Accordingly, we propose a new theoretical framework to delineate the relationships between hand hygiene and surface hygiene. In addition, the performance of a model based on this framework that used real-world behavioural data from a graduate student office is reported. Moreover, a coupled hygiene criterion for heterogeneous networks is derived. This criterion stipulates that the product of the pathogen-removal rates for hands and surfaces must exceed a cleaning threshold to ensure the exponential decay of contamination. Failure to meet this threshold results in a non-zero steady prevalence of contamination. Furthermore, the cleaning threshold increases as the numbers of surfaces and hands increase, highlighting the significant impact of network structures on hygiene practices. Thus, extensive cleaning may be necessary in crowded indoor environments with many surfaces and occupants, such as cruise ships, to prevent super-large outbreaks of, for example, noroviral infections. Overall, the findings of this study reveal how improved and integrated hygiene control can prevent fomite transmission. [Display omitted] • A new coupled hygiene criterion derived for heterogeneous surface touch networks. • Combined surface and hand hygiene is required for contamination elimination. • Random cleaning is ineffective in heterogeneous surface touch networks. • Large surface touch networks pose a greater hygiene challenge than smaller ones. [ABSTRACT FROM AUTHOR]

Helicobacter pylori infection (HPI) is extremely common in the world, particularly in less developed areas, but the primary causes of childhood HPI are unspecified. To determine the influences of exposure to home environmental factors (HEFs), outdoor air pollutants (OAPs), and parental stress (PS), as well as their interactions on children's HPI. We implemented a retrospective cohort study with 8689 preschoolers from nine districts at Changsha, China, was conducted using questionnaires to collect data of health and HEFs. Temperature and OAPs data were collected from ten and eight monitoring stations, individually. Temperature and OAPs exposures were calculated for all home addresses using the inversed distance weighted (IDW) model. Multiple logistic regression analysis was carried out to determine the separate and combined impacts of HEFs, OAPs, and PS on HPI. Children's HPI was significantly associated with exposure to moisture-specific indoor allergens in one-year preceding conception, gestation, and first year, smoke-specific air pollution throughout life, and plant-specific allergens in previous year. Outdoor exposures to CO in the 7th-9th month before conception, as well as PM 2.5 in the second trimester and previous year, were associated with HPI, with ORs (95 % CIs) of 1.22 (1.05–1.41), 1.23 (1.03–1.46), and 1.33 (1.14–1.55). Parents' socioeconomic and psychological stress indicators were positively related to HPI. High socioeconomic indicators and psychological stresses increased the roles of indoor renovation and moisture indicators as well as outdoor SO 2 , PM 2.5 and O 3 on children's HPI over their entire lives. Parental psychological stress interacts with indoor renovation-specific air pollution, moisture- and plant-specific allergens, as well as outdoor traffic-related air pollution on HPI, during a critical time window in early life. Indoor and outdoor air pollutants, as well as allergens, separately and interactively exert important effects on childhood HPI, lending support to the "(pre-) fetal origin of HPI" hypothesis. [Display omitted] • Parental stress is associated with children's Helicobacter pylori infection (HPI). • Smoke-, moisture-, and plant-specific indoor air pollution and allergens increase HPI risk. • CO and PM 2.5 exposure played key roles in the development of childhood HPI. • Parental socioeconomic and mental stresses increase HPI risk of home renovation and dampness. • High parental socioeconomic stress enhances the impact of outdoor SO 2 and PM 2.5 on HPI. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pinewood VOC emissions improve atopic dermatitis disease parameters and dysbiosis. • Beneficial effects on disease phenotype and skin microbiome are dose-dependent. • Direct pinewood VOC exposures in mouse and human in vitro models. • Environmental compounds useful in prevention and/or control of atopic skin disease. Pinewood, increasingly used in construction and interior fittings, emits high amounts of volatile organic compounds (VOCs), which tend to accumulate in indoor air. Whether indoor VOCs affect the development of atopic dermatitis (AD) is a matter of debate. We aimed to evaluate the effects of pinewood VOCs on the development of AD-like inflammatory phenotype and linked microbiome alterations, both hallmarks of AD. An oxazolone-induced mouse model of AD was exposed to three different VOC concentrations emitted by pinewood plates throughout the experiment. The disease course and associated immunological and microbiological changes were evaluated. To validate and translate our results to humans, human keratinocytes were exposed to a synthetic pinewood VOCs mixture in an AD environment. Pinewood emitted mainly terpenes, which at a total concentration of 5 mg/m3 significantly improved oxazolone-induced key AD parameters, such as serum total IgE, transepidermal water loss, barrier gene alteration, inflammation, and dysbiosis. Notably, exposure to pinewood VOCs restored the loss of microbial richness and inhibit Staphylococci expansion characteristic of the oxazolone-induced mouse AD model. Most beneficial effects of pinewood VOCs were dose-dependent. In fact, lower (<3 mg/m3) or higher (>10 mg/m3) pinewood VOC levels maintained only limited beneficial effects, such as preserving the microbiome richness or impeding Staphylococci expansion, respectively. In the human in-vitro model, exposure of keratinocytes grown in an AD environment to a pinewood VOCs mixture reduced the release of inflammatory markers. In conclusion, our results indicate that airborne phytochemicals emitted from pinewood have beneficial effects on an AD-like phenotype and associated dysbiosis. These investigations highlight the effects of terpenes as environmental compounds in the prevention and/or control of atopic skin disease. [ABSTRACT FROM AUTHOR]

Background: Estimated 1.1 million children developed tuberculosis (TB) globally in 2020. Household air pollution has been associated with increased respiratory tract infections among children. Nonetheless, there are scarce data regarding the association of indoor environment with pediatric TB. Objectives: To determine the association of indoor urban environment and conventional risk factors for pulmonary TB among children 1–12 years and to discern the differences of these factors among younger (1–5 years) and older children (6–12 years). Materials and Methods: We conducted an age-matched case–control study among children in 2 hospitals (tertiary and secondary care) in megacity, Karachi, Pakistan. A total of 143 pulmonary TB cases, diagnosed on Pakistan Paediatric Association Scoring Chart for Diagnosis of Tuberculosis (PPASCT), were compared with 286 age-matched controls (ratio 1:2). Indoor urban environment and other conventional risk factors were ascertained through a questionnaire and analyzed by conditional logistic regression. Results: Overall, being a female child [matched odds ratio (mOR): 2.03, 95% confidence interval (CI): 1.16–3.53], having household TB contact (mOR: 8.64, 95% CI: 4.82–15.49), open kitchen for cooking in household (mOR: 1.99, 95% CI: 1.59–5.66), and poorly ventilated house (mOR: 2.37, 95% CI: 1.09–3.65) increased the risk of TB among children (1–12 years). Open kitchen was a risk factor for younger children (1–5 years), whereas poorly ventilated house and being female child was a risk factor for older children (6–12 years), respectively. Conclusions: This study strengthens the evidence that a poor indoor environment increases the risk for childhood TB. Concerted efforts are needed to improve the indoor air environment in urban areas for prevention of TB in addition to addressing the conventional risk factors. [ABSTRACT FROM AUTHOR]

In complex indoor environments, there is often no Line of Sight (LOS) path between the transmitter and the receiver due to walls, moving people, and many other obstacles. Traditional localization method based on LOS measurement is no longer available which provides lower localization accuracy in Non-Line of Sight (NLOS) environments. In response to this problem, this paper proposes a joint localization algorithm for scatterers and target user based on indoor prior information in NLOS scenarios. The algorithm makes use of the prior localization information of the access point (AP) and the wall to determine the position of the scatterers and target user simultaneously. Since the established constrained optimization problem is non-convex which is a difference of convex (DC) problem, it is transformed into a convex one based on a Taylor series expansion (TSE) method before it is solved. At the same time, as only a single AP signal can be received normally, the proposed method is then extended to the scenario with only one AP. Simulation and real-world testing results both show that not only the proposed method based on multiple APs, but also the method based on a single AP achieve high positioning accuracy, which are better than the existing positioning methods mentioned in this article as well. [ABSTRACT FROM AUTHOR]

Ventilation system performance in high‐rise multi‐unit residential buildings (MURBs) has a significant impact on resident wellbeing. While the importance of ventilation is well established, it is commonly overlooked since underperformance often goes undetected. This article presents a review and synthesis of ventilation system performance in high‐rise MURBs located in cold climates as it relates to the three pillars of sustainability: economic (capital and operational cost), social (airflow control, indoor environmental quality, and occupant behavior and interactions), and ecological (energy and carbon). A meta‐analysis revealed previous ventilation system designs generally prioritized economic sustainability, specifically, capital cost. However, priorities have recently shifted toward social and ecological sustainability. While this shift is positive, there is insufficient empirical evidence showing which ventilation system most effectively supports it. The decentralized heat/energy recovery ventilator (HRV/ERV) system shows the potential to improve upon the social and ecological sustainability of previous designs, such as the centralized pressurized corridor system, but the interconnected nature of performance metrics can cause improvements to one to negatively impact others. Therefore, further research is required to enhance ventilation system performance in cold climate, high‐rise MURBs, and facilitate decision‐making while designing and retrofitting these systems. [ABSTRACT FROM AUTHOR]

Control of temperature and relative humidity in storage areas and exhibitions is crucial for long-term preservation of cultural heritage objects. This paper explores the possibilities for developing a proactive system, based on a machine-learning model (XGBoost), for predicting the occurrence of unwanted indoor environmental conditions: either a too high or a too low relative humidity, within the forthcoming 24 h. The features used in the model were hourly indoor and outdoor climate recordings, and it was applied to two indoor heritage environments; a storage facility and a church building. The test accuracy (f1-score) of the model was good (0.93 for high RH; 0.93 for low RH) when applied to the storage building, but only 0.78; 0.62 (high RH; low RH) for the church building test. Challenges encountered include difficulties in obtaining good historical climate data sets for training and testing the model, and the dependency of external IT systems, which, if they fail, inactivates the model without a warning. Several issues call for more research: A desirable improvement of the model would be predictions for periods longer than 24 h ahead, still maintaining a high test accuracy. Further perspectives of using machine learning for indoor environmental forecasting could be for indoor air pollution, or energy consumption due to climate control. [ABSTRACT FROM AUTHOR]

This paper examines the large-scale path loss models for an indoor corridor environment at frequencies of 28 and 38 GHz. The measurement environment consists of an indoor corridor with both line-of-sight (LOS) and non-line of sight (NLOS) scenarios using vertical–vertical (V–V) and vertical–horizontal (V–H) antenna polarizations. The single-frequency close-in (CI), floating intercept (FI), free space large-scale path loss models and measured data from the measurement campaign were used to evaluate the performance analysis. The paper also focuses on various parameters, such as standard deviation, path loss exponent (PLE), accuracy, simplicity, and stability of the models. The analysis focuses on the peculiarity of the effect of the wall proximity on the path loss parameters as well as comparisons with the parameters in some of the reviewed literature studies. The FI and CI models produce comparable results for both antenna polarizations and clearly fit with the measured path loss. The PLE, with the highest value of 3.33 at 38 GHz (V–H), is much higher in the NLOS scenario with V–H polarization due to the signal degradation along the path from the transmitter (Tx) to the receiver (Rx). This is because there is no direct LOS between the Tx and Rx antennas. The Rx only relies on signal diffractions and reflections from obstacles as it transmits through the path from the Tx antenna. The path loss measurements and model analysis presented here are useful in designing 5G wireless communication systems for indoor environments, particularly for power budget calculations. [ABSTRACT FROM AUTHOR]

The paper analyses thermal comfort in intelligent and traditional buildings in Poland. It provides a comprehensive study on the subjective assessment of indoor environment conditions as well as on parameters that influence human thermal sensations and preferences. Direct measurements of physical parameters (e.g., air and globe temperature, relative humidity) as well as simultaneously conducted anonymous questionnaire studies were used to provide the necessary data. The study covered all seasons and a large number of participants representing various age groups and body build types, who completed a total of 1778 questionnaires. The results indicate that typically smart buildings offer higher levels of thermal comfort than the traditional ones and that people tend to prefer warmer environments. Moreover, it has been observed that the BMI index, air movement and the number of people per surface area can have an impact on the perceived thermal sensations. [ABSTRACT FROM AUTHOR]

Quilts play a vital role in the thermal comfort of sleeping people. This study aims to investigate the comfortable indoor temperatures and thermal responses when people sleep in different quilts. The experiment tested three kinds of quilts (down, silk, and polyester), and each kind of quilt involved six filling weights. Sixteen participants (eight males and eight females) conducted whole‐night sleeping trials to acquire skin temperatures, bedding temperatures, and thermal perceptual responses. The lower and upper limits of air temperatures (Tlower$$ {T}_{lower} $$ and Tupper$$ {T}_{upper} $$) for comfortable sleeping were obtained. The results indicated that thermal sensation votes were in the range from 0.1 (close to "neutral") to 1.3 (close to "slightly warm") when participants felt comfortable and preferred "no change" in thermal preference. The corresponding comfortable mean skin and bedding temperatures were 34.6 ~ 35.2°C and 31.2 ~ 32.7°C, respectively. Tlower$$ {T}_{lower} $$ and Tupper$$ {T}_{upper} $$ had good linear correlations with bedding insulations. For the same bedding insulation, the Tlower$$ {T}_{lower} $$ and Tupper$$ {T}_{upper} $$ were highest for using silk quilts, followed by down and polyester quilts. The comfort ranges of air temperatures and quilt insulations were finally determined. The findings may benefit understanding the thermal requirement of quilts and help people select and design quilts to achieve thermal comfort. [ABSTRACT FROM AUTHOR]

In indoor low-texture environments, the point feature-based visual SLAM system has poor robustness and low trajectory accuracy. Therefore, we propose a visual inertial SLAM algorithm based on point-line feature fusion. Firstly, in order to improve the quality of the extracted line segment, a line segment extraction algorithm with adaptive threshold value is proposed. By constructing the adjacent matrix of the line segment and judging the direction of the line segment, it can decide whether to merge or eliminate other line segments. At the same time, geometric constraint line feature matching is considered to improve the efficiency of processing line features. Compared with the traditional algorithm, the processing efficiency of our proposed method is greatly improved. Then, point, line, and inertial data are effectively fused in a sliding window to achieve high-accuracy pose estimation. Finally, experiments on the EuRoC dataset show that the proposed PLI-VINS performs better than the traditional visual inertial SLAM system using point features and point line features. [ABSTRACT FROM AUTHOR]

Antibacterial filtration materials have been used effectively to control biological pollutants and purify indoor air. This study aimed to assess the antibacterial capability of three fiber filter materials treated with triclosan: glass fiber (GF), non-woven fabric (NF) and chemical fiber (CF). Triclosan was loaded onto the filtration materials by the impregnation method. The triclosan-treated filter materials exhibited antibacterial zones obviously: the average antibacterial bands against E. coli were 11.8 mm (GF), 13.3 mm (NF) and 10.5 mm (CF); against S. albus, they were 25.5 mm (GF), 21.0 mm (NF) and 23.5 mm (CF). The percent reductions of bacteria for the antibacterial air fiber materials treated with triclosan against E. coli were 71.4% (CF) and 62.6% (GF), while the percent reductions against S. albus were 61.3% (NF) and 84.6% (CF). These findings could help to reduce the transmission and threat of epidemic and purify the environment through the use of environmentally friendly antibacterial filter fibers. [ABSTRACT FROM AUTHOR]

We consider the problem of localizing a smartphone user using received signal strength (RSS) measured by a set of known network nodes in a harsh indoor environment. While the RSS of a wireless signal can be conveniently accessed, using it to estimate location is non-trivial in the presence of multipath propagation, shadowing and radio interference. Auxiliary information, such as the indoor building map and user's orientation information, potentially can help to improve localization performance. As the indoor layout is usually known as a priori, a user's moving direction or orientation in a given indoor map may contain valuable information to assist for reducing location ambiguities at estimation, typically when the radio signal channel is corrupted with noise. In this paper, we propose a double-layer hidden Markov model (DHMM) within a Bayesian learning framework for combining user orientation information and processing RSS data in the localization process to deal with RSS fluctuations induced by human body shadowing and multipath interference. Simulation and experimental results show that incorporating user orientation can potentially provide promising indoor positioning results. [ABSTRACT FROM AUTHOR]

The complex and uncertain causes of sick building syndrome (SBS) have become one of the most challenging and hot issues worldwide. Studies on the correlation between indoor environment and SBS based on local characteristics are relatively limited in China. We studied typical SBS risk factors related to the indoor environment and lifestyle in two northern Chinese cities. The study population was drawn from parents of pre‐school children in randomized daycare centers in Taiyuan, Shanxi, and Urumqi, Xinjiang, China (N = 6838). Data on SBS and indoor environment were obtained from cross‐sectional questionnaires. Odds ratios (OR) were estimated by multilevel logistic regression and adjusted using gender, atopy, own smoking, home size, and dampness index. Results showed that location, homeownership, year of construction completion, changes in the indoor environment (new furniture and decorations), and changes in indoor air (smoking, burning mosquito repellent and incense, cooking fuels including electricity, natural gas, coal, and wood) might contribute to different levels of SBS in Chinese adults, including eye, nasal, throat, dermal symptoms, and headache and tiredness. The results of the subgroup analysis suggest city and gender differences in susceptibility. Daily cleaning, window opening, and improved ventilation effectively improved SBS. People should improve their indoor environment and lifestyles based on sensitivity factors, gender, and geographic characteristics to reduce SBS risks. [ABSTRACT FROM AUTHOR]

As more and more people stay inside the building for a long time, the indoor environment has a great effect on their health, mood, and work efficiency. Electroencephalography (EEG) signals reflect electrical activity originating from neuronal firing when a task or activity is performed. Since there was no study on the effect of indoor air on nerves, this study utilized EEG to preliminarily explore the brain functions of subjects during working memory tasks with different difficulties. The subjects were divided into two groups according to the volatile organic compounds (VOCs) as odor irritants in the air. We expected to find the difference in subjects' EEG signals between VOCs and low‐VOCs. The EEG signals from 60 electrodes were analyzed by event‐related potential (ERP), event‐related spectral power (ERSP), and correlation network methods to describe the brain activity. We compared the results of subjects in VOCs and low‐VOCs and found significant differences between ERP and ERSP in the alpha band during a simple working memory task. Subjects were more sensitive to the VOCs in simple tasks than in complex tasks. Our work provided evidence of odor effects on brain functions and could be used to guide the design of indoor odor in home, offices, and classrooms. [ABSTRACT FROM AUTHOR]