High-rise Apartment Buildings Research Articles

Mitigating indoor air pollution in UAE's high-rise apartment buildings: a study on eco-friendly materials and adsorbents

PurposeThis study aims to evaluate the efficiency of various techniques for enhancing indoor air quality (IAQ) in construction. It analyzed the alterations in the concentration of indoor air pollutants over time for each product employed in controlling pollution sources and removing it, which included eco-friendly substances and adsorbents. The study will provide more precise and dependable data on the effectiveness of these control methods, ultimately supporting the creation of more efficient and sustainable approaches for managing indoor air pollution in buildings.Design/methodology/approachThe research investigates the impact of eco-friendly materials and adsorbents on improving indoor air quality (IAQ) in Dubai's tall apartment buildings. Field experiments were conducted in six units of The Gate Tower, comparing the IAQ of three units built with “excellent” grade eco-friendly materials with three built with “good” grade materials. Another experiment evaluated two adsorbent products (H and Z) in the Majestic Tower over six months. Results indicate that “excellent” grade materials significantly reduced toluene emissions. Adsorbent product Z showed promising results in pollutant reduction, but there is concern about the long-term behavior of adsorbed chemicals. The study emphasizes further research on household pollutant management.FindingsThe research studied the effects of eco-friendly materials and adsorbents on indoor air quality in Dubai's new apartments. It found that apartments using “excellent” eco-friendly materials had significantly better air quality, particularly reduced toluene concentrations, compared to those using “good” materials. However, high formaldehyde (HCHO) emissions were observed from wood products. While certain construction materials led to increased ethylbenzene and xylene levels, adsorbent product Z showed promise in reducing pollutants. Yet, there is a potential concern about the long-term rerelease of these trapped chemicals. The study emphasizes the need for ongoing research in indoor pollutant management.Research limitations/implicationsThe research, while extensive, faced limitations in assessing the long-term behavior of adsorbed chemicals, particularly the potential for rereleasing trapped pollutants over time. Despite the study spanning a considerable period, indoor air pollutant concentrations in target households did not stabilize, making it challenging to determine definitive improvement effects and reduction rates among products. Comparisons were primarily relative between target units, and the rapid rise in pollutants during furniture introduction warrants further examination. Consequently, while the research provides essential insights, it underscores the need for more prolonged and comprehensive evaluations to fully understand the materials' and adsorbents' impacts on indoor air quality.Practical implicationsThe research underscores the importance of choosing eco-friendly materials in new apartment constructions for better IAQ. Specifically, using “excellent” graded materials can significantly reduce harmful pollutants like toluene. However, the study also highlights that certain construction activities, such as introducing furniture, can rapidly elevate pollutant levels. Moreover, while adsorbents like product Z showed promise in reducing pollutants, there is potential for adsorbed chemicals to be rereleased over time. For practical implementation, prioritizing higher-grade eco-friendly materials and further investigation into furniture emissions and long-term behavior of adsorbents can lead to healthier indoor environments in newly built apartments.Originality/valueThe research offers a unique empirical assessment of eco-friendly materials' impact on indoor air quality within Dubai's rapidly constructed apartment buildings. Through field experiments, it directly compares different material grades, providing concrete data on pollutant levels in newly built environments. Additionally, it explores the efficacy of specific adsorbents, which is of high value to the construction and public health sectors. The findings shed light on how construction choices can influence indoor air pollution, offering valuable insights to builders, policymakers and residents aiming to promote public health and safety in urban living spaces.

Social impacts of living in high-rise apartment buildings: The effects of buildings and neighborhoods

ABSTRACT Social networks, social cohesion, and place attachment are positive social impacts that can stimulate people’s quality of life. High-rise apartment buildings are often criticized for their negative social impacts, such as social isolation and low levels of interaction and social cohesion. However, there is still insufficient empirical evidence on the relationships between neighborhood social networks, social cohesion, place attachment, and loneliness of high-rise apartment residents and how they are affected by the physical environment and neighborhood satisfaction. This study uses structural equation modeling (SEM) to investigate these relationships using data collected in four high-rise apartment complexes in Hanoi, Vietnam. While the number of neighbors in someone’s social network is found to stimulate social cohesion, which can foster neighborhood attachment and reduce feelings of loneliness, the possibility of improving these social impacts is affected by urban contexts, site properties, and the ability to provide communal spaces within and surrounding the buildings.

Crack Damages in Exterior Wall Structures of Korean High-Rise Apartment Buildings Based on Nonlinear Finite Element Analysis

Crack Damages in Exterior Wall Structures of Korean High-Rise Apartment Buildings Based on Nonlinear Finite Element Analysis

Safety and Security of the Environment for Flat Dwellers on the Granting of Building Rights Title (HGB) on Management Rights (HPL) for 80 Years

The development of high-rise apartment buildings is an alternative solution to meet the housing and settlement needs. After the enactment of the Job Creation Law (UUCK), the Government issued Regulation No. 18 of 2021 concerning Management Rights, Land Rights, High-rise Apartment Units, and Land Registration. In this regulation, the period of Building Use Rights (HGB) over Management Rights (HPL) can be granted for 80 (eighty) years for the construction of high-rise apartments. This study was conducted to determine whether granting HGB over HPL for 80 (eighty) years is appropriate to be implemented and whether it potentially threatens the safety and environmental security of the high-rise apartment residents. The study results show that based on the prevailing regulations, granting HGB over HPL for 80 (eighty) years is appropriate because there is periodic inspection of the feasibility of the function every 5 (five) years as a requirement for certificate of feasibility of function (SLF) extension. However, in terms of building reliability, granting HGB over HPL for high-rise apartments for 80 (eighty) years still potentially poses a threat to the safety and environmental security of the residents because the building's capability will decrease in strength that affects the building's reliability. Another risk arises because the sanctions given for the negligence of periodic inspections on the building's reliability in the process of extending SLF are only in the form of administrative sanctions, so more severe sanctions such as criminal sanctions need to be imposed on violators.

Benefits assessment of cool skin and ventilated cavity skin: Saving energy and mitigating heat and grid stress

This study assessed the energy-saving and climate-adaptive potential of cool skin and ventilated cavity skin facade technologies in Seoul's high-rise apartment buildings. We created weather scenarios for historical, mid-term future, and long-term future conditions using Coordinated Regional Downscaling EXperiment (CORDEX) method. Building energy simulations were conducted on a South Korean high-rise apartment model to evaluate their performance under different weather conditions. The results indicate that cool skin and ventilated cavity skin technologies can save cooling energy during summers but lead to heating energy penalties in winters. Ventilated cavity skin outperforms cool skin, offering better cooling energy savings and reduced heating penalties. Combining both technologies yields the highest overall energy savings, with 7 %, 9 %, and 10 % cooling energy savings for cool skin, ventilated cavity skin, and the combined package, respectively. However, cool skin increases heating energy consumption by 5 %, while ventilated cavity skin has minimal impact on heating energy. These envelope technologies also reduce peak electricity demand by at least 5 %, 8 %, and 9 %, respectively. They contribute to heat stress reduction, enhance resilience, and decrease extreme heat risks for occupants during power outages by at least 18 % under various weather conditions. Considering the prevalence of aging high-rise apartments in South Korea, adopting these envelope renovation strategies can effectively reduce cooling loads, enhance thermal comfort, and boost resilience under future climates, while avoiding costly reconstruction.

URBAN DEVELOPMENT AND WASTE MANAGEMENT PLANNING IN KABUL NEW CITY, AFGHANISTAN: A CASE STUDY

The municipal solid waste collection system and services of existing Kabul City are not acceptable socially, economically, and environmentally. This study was carried out in 2020–2021 for the Phase-1 area of Kabul New City (KNC). The study aims to analyze different MSWCSS for the KNC area and choose the best option during the planning stage. The average incremental cost for different collection systems was determined, and the results show that the total annualized cost (AN) of the proposed waste collection system (PWCS) is 855.3699 AFN/tonne, while the total operation and maintenance cost (OP) is 577.1235 AFN/tonne. The AN and OP of the stand-alone underground waste collection system (SAUWCS), tailored collection point system, traditional (prevailed) system, and alley waste collection system (AWCS) are 911.3032 AFN/tonne and 499.9017AFN/tonne, 1,681.762 AFN/tonne and 1,267.28 AFN/tonne, 308.9254 AFN/tonne and 186.3363 AFN/tonne, and 716.7706 AFN/tonne and 410.5375 AFN/tonne, respectively. The social and environmental analysis for the PWCS, SAUWCS, existing system, and AWCS obtained scores of 19, 29, -6, 17, and -5, respectively. From the cost-benefit analysis, it has been proposed that for the PWCS of low-rise residential areas, three wheelie bins of different colors will be provided to each housing unit. The total costs per tonne of solid waste for the PWCS, SAUWCS, TCPS, and traditional system are 2,832.1952, 3,638.137205, 3,888.6272, 751.45984, and 1,975.8152, respectively. For the PWCS of residential areas, chute waste collection systems are planned for high-rise apartment buildings and SAUWCSs are planned in commercial areas.

ASSESSMENT OF THE FIRE RESISTANCE OF BUILDINGS FROM FIREPROOF REINFORCED CONCRETE BUILDING STRUCTURES

The authors conducted an analysis of the current state of evacuation of low-mobility population groups from high-rise residential buildings in the event of a fire. The analysis of the literature made it possible to formulate a number of obstacles to the effective evacuation of people from high-rise residential buildings. Norms in the field of fire safety are not perfect and, as a rule, are aimed at ordinary categories of citizens. The goal of approaches to evacuation calculations is to reduce the time it takes to evacuate residents of a high-rise building in the event of a fire. The authors substantiated the possibility of safe self-evacuation in the event of a fire of the less mobile population groups using fire elevators. Mathematical and graphical calculations of people's evacuation time were carried out using the Pathfinder software complex with the use (without use) of fire elevators. The authors performed a mathematical calculation of the time of evacuation of people and the time of blocking by dangerous factors of fire evacuation routes during a fire in accordance with the methodology of DSTU 8828:2019 Fire safety. Terms. Kyiv: Technical Committee "Fire Safety and Fire Fighting Equipment". To confirm the effectiveness of using fire elevators for the evacuation of people belonging to the M4 population groups with limited mobility (disabled people who move around in wheelchairs), the calculation part was performed. The object of the calculations is a high-rise apartment building on the street. Baidy Vyshnevetskoho, 68 in Cherkasy. The authors determined the dependence of the evacuation time on the movement parameters of people of different mobility groups. The authors compared calculations of evacuation time by stairwell and using fire elevators. Fire elevators are effective when evacuating people from floors for the category of mobility group M4. The researchers proposed management solutions to increase the level of fire safety, ensure the constant readiness and operability of fire elevators for evacuating people with reduced mobility from high-rise residential buildings. Keywords: evacuation routes, evacuation exits, high-rise residential buildings, fire elevators, evacuation time.

Passive Window Energy Performance in Buildings: Modeling of Apartment Buildings in Indonesia

Along with urban growth in urban areas and energy consumption, which continues to increase every year, the selection of windows in the initial design is essential to obtain buildings that are not energy intensive. Selecting the correct window in the blueprint design reduces building energy consumption. Smart windows, especially thermochromic windows, are one of the most promising window technologies because they are the most economical and have passive control with zero energy input, which holds good promise for energy-saving applications. Apart from that, double-glazing windows are also frequently used in energy-saving applications. Therefore, a study compared the energy-saving potential of thermochromic and double-glazing windows to clear glass windows, using computer modeling through EnergyPlus, in high-rise apartment buildings in cities throughout Indonesia's diverse climates. From the modeling results, total energy consumption can be reduced by around 8.91% to 10.96% of total building energy consumption by replacing the conventional clear glass with double-glazing windows or more able to reduce about 20.22% to 24.19% by replacing the conventional clear glass with thermochromic windows. Furthermore, this potential varies depending on geometric shapes, materials, building facades, local climate, and building orientation. Nevertheless, considering the potential benefits, these windows are highly suitable for application in buildings seeking to reduce their energy consumption and improve energy efficiency.

Knowledge, Attitude, And Challenges of High-Rise Building Community Towards Waste Segregation and Recycling Practice in Metropolitan Kuala Lumpur, Malaysia

The increasing population of modern cities contributes to the development of more residential high-rise buildings as well as waste management challenges. Recycling and waste separation can be a challenge in high rise apartment buildings due to the high volume of residents and limited space for waste management. Therefore, the objectives of this study is to investigate the knowledge, attitude, and challenges of high-rise building communities towards waste segregation and recycling. Using cross-sectional analysis, online questionnaires were distributed to target respondents in Sentul Kuala Lumpur. Data were collected from 375 residents of high-rise buildings. The results show that the high-rise community has modest knowledge (57%) and challenges (61%) to practice waste sorting and recycling, however, showed a good attitude (81%) towards it. Waste separation and recycling were influenced by sociodemographic factors of education (p = 0.05), ownership (p = 0.02), marital status (p = 0.01), and floor of living (p = 0.02). There is positive correlation between knowledge an attitude (r = 0.57, p = 0.26), but negative correlation between knowledge and challenges (r = - 0.25, p = 0.0001). The result also indicates that this community lack information and knowledge to practice waste sorting and recycling. Intervention is required to convey the information to these dwellers.

Vertical dispersal of Aedes albopictus within multi-story buildings in downtown Shanghai, China

BackgroundShanghai has numerous high-rise apartment and office buildings, but the effects of these high-rise spaces on the vertical dispersal, oviposition and blood feeding behavior of Aedes albopictus are unknown.MethodsIn six multi-story building blocks in downtown Shanghai, 174 mosq-ovitraps (MOT) were placed both indoors and outdoors for Ae. albopictus collection at different vertical heights from the 1st to 6th floors and a terrace on the 8th floor. Collections were made for 4 months. The human landing catch (HLC) method for Ae. albopictus monitoring was also conducted on 6 consecutive days on six floors of two of the six buildings to study the feeding behavior of Ae. albopictus at different heights.ResultsBoth MOTs and HLCs collected Ae. albopictus at all monitored heights. The vertical distribution, oviposition pattern and biting behavior varied significantly among the seven heights (1st–6th floors and 8th floor) (mosq-ovitrap index (MOI): X2 = 140.616, df = 6, P < 0.001; HLC: F (5, 138) = 15.111, P < 0.001). The MOI at low heights (1st + 2nd floors) was significantly higher than that at medium (3rd + 4th floor, P < 0.001) and high heights (5th + 6th floors, P < 0.001), and there was no significant difference in the MOI for the 3rd–6th floors. The outdoor MOIs were significantly higher than indoor MOIs at all heights (outdoor 23.09% vs. indoor 9.58%, X2 = 74.121, df = 1, P < 0.001). Aedes albopictus HLC density on the ground floor was significantly higher than that on all other heights (5.04 vs. 0.13, 0.29, 0.58, 0.79 and 1.50 per half hour, P < 0.05), while no difference was detected among the heights above the ground floor (P > 0.05).ConclusionsAedes albopictus is more common near the ground level, but it can easily disperse to higher floors in the multi-story buildings of urban Shanghai. No significant differences in Ae. albopictus density were detected within the 3rd–6th floors using MOT or HLC. This suggests that Ae. albopictus might also disperse to areas above the 6th floor and seek hosts there. Aedes albopictus prefers to oviposit outdoors; however, Ae. albopictus was also able to inhabit, oviposit and engage in blood-feeding behavior indoors on different floors. The three-dimensional dispersal pattern of Ae. albopictus in urban areas could facilitate arbovirus transmission and increase the difficulty of dengue control.Graphical abstract

Value activation to increase consumers' intention to purchase green apartments

PurposeThis study examines the motivational forces of self-transcendence and self-enhancement values in consumers' green apartment purchase intention since the values have been seen as the key determinants of environmental beliefs and concerns that motivate pro-environmental behaviour adoption amongst consumers regardless of external barriers. Additionally, this study identifies the role of environmental content in strengthening the effects of self-transcendence value.Design/methodology/approachSurvey data were collected from 234 residents of three high-rise apartment buildings in Hanoi, Vietnam. Measure reliability and validity were tested by confirmatory factor analysis (CFA) before hierarchical ordinal least squares regression (OLS) was conducted to test the hypotheses.FindingsThe research results reveal a significant positive relationship between self-transcendence value and consumers' green apartment purchase intention. However, environmental problem-related content exposure was found to weaken the effect of self-transcendence value on the purchase intention whilst the effect was reported to be strengthened by pro-environmental action-related content exposure.Originality/valueTheoretically, this study emphasizes the importance of interaction effects between external factors and personal values in explaining consumer's decisions and behaviours. Practically, the research results provide valuable insights for marketers and developers into fostering the adoption of green building apartments amongst consumers.

OTTV'S Assessment on Thermal Performance of High-Rise Apartment Buildings in Penang

This study evaluates the envelope thermal performance of high-rise apartment buildings in Malaysia, which are being largely dominated due to the high economic development and increased population. The evaluation was conducted using the Overall Thermal Transfer Value (OTTV), which is the key tool used in the Green Building Index to assess the Energy Efficiency of buildings. Different high-rise apartment buildings were selected with different architecture styles, to account for several periods of building construction. The OTTV value was calculated for the west-oriented façade of the selected buildings, which is considered as a critical orientation that receives high solar radiation. The results showed that four out of the five investigated buildings achieved the minimum requirements for the OTTV, i.e., less than 50 W/m². The maximum and minimum OTTV values with the buildings’ original design were 82.60 W/m² and 41.54 W/m², respectively. However, one of the buildings achieved a lower OTTV value with the installation of shading devices by the owners, i.e., decreased from 48.39 W/m² to 37.60 W/m². The solar radiation penetration through the fenestration was found to be the major contributor to the total OTTV, while it can be controlled by the shading devices. Besides, using dark paints increased the heat conduction through the opaque walls by more than double compared to light paints. This study shows that some design considerations, such as paint colour, shading devices, and glazing material, can have a great influence on the heat gain in buildings.

High-rise apartment quality evaluation and related demographic factors: lesson from RentSafeTO programme

ABSTRACT With the rapid increase in urbanization and the number of residents living in high-rise apartment buildings, the quality of living environments in terms of the facility, safety and hygiene of high-rise housing has become an important topic. Although numerous studies have investigated occupant satisfaction through subjective assessment, only few studies have used objective assessment methods, such as expert evaluation, to elucidate the quality of high-rise apartments and the related occupancy factors. According to the dataset from Toronto's RentSafeTO programme, which provides the results for 9928 high-rise apartments evaluated using 20 quality indicators, this study conducted a factor analysis and identified two main factors for assessing high-rise housing: building structure and building facilities. Furthermore, this study used multiple regression models and census data to analyse the housing quality at the regional level. The results of social housing and private housing differed. Labour force attributes, education, immigration and ethnic origin significantly affected the quality of private housing. The results provide important directions for the post-occupancy evaluation of high-rise apartments. In addition, demographic factors significantly affected residential quality. This study provides a basis for the government to formulate equal and unbiased support for high-rise building maintenance and management.

Performance evaluation of high-rise apartment building using pushover analysis

Indonesia is a developing country that is experiencing rapid development growth. According to the Central Statistics Agency, in 2020 the population of Indonesia will be 270.20 million people. The increase in population from year-to-year results in increasingly narrow lands for development. Therefore, developers and businesspeople make the best use of this opportunity in the world of construction by carrying out developments, including high-rise apartments. As an earthquake-prone area, the planning process for buildings, especially tall buildings in Indonesia, must be carried out very carefully by considering the strength of the structure against high-intensity earthquake loads. Risk reduction strategies can be implemented through building vulnerability assessment by checking structural performance using pushover analysis. In this study, the performance of a 32-storey apartment building was examined using the pushover analysis method. The resulting calculation is that the performance of the structure is 0.0023 for the lateral direction and 0.0113 for the transverse direction. Through the ATC 40 method it is known that the result of structural performance is Damage Control, where after an earthquake the building is still habitable.

Увеличение этажности жилых зданий как элемент концепции «Компактный город» (на примере Казани)

The concept of “compact city” involves the intensive development of the central and middle zones of large settlements by increasing the efficiency of using the territories that have the greatest value. One of the directions contributing to the implementation of this concept, which consists in the development of the vertical component of the city, increasing the height and number of floors of buildings, is known in geourbanism as “superurbanization”. The increase in the number of floors of buildings is a modern trend in the development of cities in almost all highly urbanized countries. The purpose of this work is a spatiotemporal analysis of changes in the number of floors of residential buildings in the city of Kazan. The authors created a register of housing construction objects in Kazan, built over the period 1860–2016, which contains information about 5317 multi-apartment residential buildings; a thematic map reflecting the distribution of residential buildings in the city of Kazan, depending on the number of floors of these objects, was built. Within the analyzed period, there was a tendency to increase the construction of residential buildings with an increased number of floors, as well as high-rise buildings. The number of high-rise apartment buildings built in 2001–2016 increased especially intensively: their number was 11.4 times higher than the same indicator for 1986–2000. As a rule, spatial differences in the number of floors of residential buildings have a clearly expressed historical conditionality and administrative height regulation: peripheral, relatively young areas (where there is no regulation on building height) are characterized by indicators of the average number of floors of buildings erected there within 12–14 units. High-altitude restrictions during construction in the central, historical part of the city led to lower average number of floors, which is 8 units. This measure is aimed at preserving the unique architectural appearance of historical buildings. The introduction and implementation of the ideas of “vertical” urbanism contribute to the spatial concentration and compact distribution of the activities of the population in the urban space.

Investigation of elevator-aided evacuation strategies for older people in high-rise elderly housing

Staircase evacuation is the major means of fire evacuation for current high-rise residential buildings. However, its feasibility may be questioned as the increasing aging population and many recent constructions of elderly community estates comprising high-rise apartment buildings. The weakness in physical strength and mobility impairment of older people may impede the successful implementation of staircase evacuation. Therefore, it is reasonable to consider facilitating older people's evacuation with elevators, shorted as elevator-aided evacuation (EAE). In order to find the most appropriate EAE strategy for high-rise elderly housing evacuation, three possbile strategy modes for EAE are proposed: horizontally rationed EAE (S1), vertically rationed EAE (S2), and refuge floor gathered EAE (S3). Using evacuation simulation to examine evacuation efficiencies of these proposed strategy modes varying in different evacuation scenarios, we find that S2 is appropriate for middle high-rise building (12 & 24 stories) evacuation; S3 is suitable for ultra high-rise building (36 & 48 stories) evacuation with a low occupants' density per floor; S1 is the most preferable for evacuation of ultra high-rise buildings (36 & 48 stories) with a high occupants' density per floor. More importantly, the ratio of occupants assigned to use elevators and stairs for evacuation needs to be regulated according to the occupancy information. Thus, a smart elevator-aided building fire evacuation scheme is suggested, which aims to determine the optimal EAE strategy according to the real-time on-site situation.

Substantiation of Passenger Elevators Maintenance Intervals Based on Studies of Modes and Conditions of Their Operation

Introduction. Maintenance is one of the factors of elevator systems safe operation. In regulatory documents, the influence of the loading mode of elevators on the frequency of maintenance is not taken into account and is assumed to be the same for objects operating in disparate conditions. This suggests the need to determine rational intervals between maintenance to ensure safe and economically feasible operation of the equipment in question. The work objective is to substantiate the required maintenance frequency of passenger elevators based on comprehensive assessments of their technical condition.Materials and Methods. The domestic and foreign experience of choosing the maintenance frequency of elevator units is considered. The paper evaluates the possibilities of substantiating the required maintenance intervals on the basis of established comprehensive assessments of technical condition, taking into account the conditions and operating modes. Since the problem has no direct analytical solution, an alternative approach is proposed. It is based on the hypothesis of the interrelation between the regulatory resource characteristics of assemblies and the modes and conditions of their operation. The authors obtained the necessary indicators through measurements in high-rise apartment buildings in Rostov-on-Don, experiments and adequate simulation modelling.Results. A structural and logical model has been developed to solve this problem. It consists of procedures that can be described in detail and clarified. A method for adjusting the maintenance frequency of elevators is proposed and tested. The standards of the system resource in terms of time and number of work cycles for the control time are summarized and tabulated. In this light, the gearbox, electric motor, brake, door drive and elevator ropes in 9-storey buildings are described at a cabin speed of ≤ 1 m/s. For example, the paper provides the calculated normative indicators:Kmcp норм — coefficient of net machine time (NMT);ncp норм — specific number of switching-on of the main drive and the doorAccording to the calculation results, Kmcp норм for the electric motor is 0.228; ncp норм for the brake is 1.065 per NMT minute. To assess the overall load level, the resulting technical condition of the elevator and its main components, a single generalized indicator is proposed — the load index WΣ. It is calculated as the sum of coefficients reflecting the relative level of load on the elevator assembly. It is established that as the resource is being depleted, while maintaining the value of time and power indicators, the estimated maintenance frequency will decrease. The recommended change threshold is 15–20 %.Discussion and Conclusion. The developed methodology for assessing the technical condition of the elevator unit allows us to develop a complex index by which we can judge the need to revise the regulatory intervals of the elevator unit assemblies. The proposed procedures are applicable to existing, installed and designed elevators. Simulation modeling in a specially developed computer program determines the main indicators of the technical condition of the power units of the elevator: the coefficient of net machine time, switching-on specific number, the power load and the share of the expired service life. Simulation modelling also takes into account the parameters of the building: population density and random external and internal influences. The method of adjusting the maintenance frequency allows you to quickly plan and optimize the costs of operating elevator equipment without losing the level of reliability and safety.

Race and Ethnicity in the Pandemic

This study begins with the historical understanding of race and its modern perspectives as a social construct amid social identity and critical race theories. Next, race and ethnicity are explored within the context of COVID-19, whereby those of non-white backgrounds are seeing different disastrous health outcomes and experiencing heightened levels of racism in the pandemic. Examples and analyses from around the world are then provided, which have resulted in health disparities and increased racism against non-white people, such as the high-rise apartment building disasters, rural Indigenous communities, and the Black Lives Matter movement. Adding fuel to the fire, there have been rumours internationally of certain ethnic groups carrying and spreading COVID-19.

Home gardening in Singapore: A feasibility study on the utilization of the vertical space of retrofitted high-rise public housing apartment buildings to increase urban vegetable self-sufficiency

In land-scarce cities, high-rise apartment buildings may provide vertical spaces for natural-light home gardening along corridors, rooftops, balconies as well as façades. The vertical space can improve not only urban environmental sustainability but also food security. Using an experimental approach, we investigated the food production potential of a high-rise public housing apartment building based on different gardening systems, food crops, and sunlight availability. A gardening prototype system for building corridors was shown to increase the unit area yield of corridor gardening by fivefold compared to a commercial trough planter system. Additionally, this commercial trough planter system was mainly for leafy vegetable production, whereas the gardening prototype system for corridors is also suitable for climbing crops, such as legumes and cucurbits. Nevertheless, because of the limited space along corridors of the apartment building and the relatively low-light levels on average, corridor gardening was estimated to meet only 0.5 % of the demand for vegetables of the residents living in the apartment building. Rooftop gardening with shallow growing medium (depth < 15 cm) was estimated to meet 3 % of demand, and façade gardening 43 %, given the larger space available. Although the vegetable production potential in this study was estimated based on a particular typology of public housing apartment buildings in Singapore, our results showed that vegetable production in public housing apartment buildings is feasible, and home gardening can produce a substantial amount of vegetables for consumption if well deployed. Governments of highly urbanized cities may wish to invest in better home garden designs for high-rise public housing apartment buildings and encourage residents’ participation in home gardening, which would increase high-rise greenery coverage and improve urban food system resilience. Future studies should also investigate the environmental sustainability and food safety aspects of home gardening in highly urbanized cities.

Predictability quantification of occupant presence in high-rise residential apartment buildings

In recent decades, many studies have attempted to develop a reliable occupancy model using either rule-based, stochastic, data-driven, or agent-based approaches. These are based on the hypothesis that occupant presence can become predictable provided sufficient knowledge and data are provided. However, a different view propounds that occupant presence could follow a random-walk pattern or become unpredictable in certain types of rooms/buildings, for example, university labs and library buildings. In this study, the authors report the predictability of occupant presence in high-rise residential apartment buildings in South Korea. The authors collected occupant presence data from 31 households over 147 days using occupancy sensors installed in each household. The predictability of occupant presence was then analyzed using the normalized cumulative periodogram (NCP) and Bartlett’s test. It was found that (1) the predictability of occupant presence is significantly influenced by temporal and spatial resolutions, (2) extending measurement periods (e.g., 7 days vs 147 days) can increase the predictability of occupant presence, (3) for a measurement period of 7 days, the occupant presence for 14 households became unpredictable, and (4) the predictability of occupant presence significantly differs among 31 households.