COVID-19: a catalyst for revitalizing mixed-use urban centers? The case of Paris

Since the mid-1990s, the French public authorities have changed regulations to allow commercial building conversions into housing. The COVID-19 crisis has affected the global economy, social connections, environmental trajectories and energy demand/supply. Countries have been considering measures to reduce the pandemic's long-term impact and since the beginning of 2020, national governments have recommended that companies facilitate remote work. Thus, COVID-19 has prompted some office building depopulation. With working from home expected to continue after the pandemic, due to technological, environmental and economic considerations, there is a growing impetus to convert empty office space into residential uses. The present research aims, through the Parisian case study, to consider the impacts of the pandemic and the acceleration of homeworking. Using a mixed qualitative and quantitative methodology, the study aims to (1) critically analyse the policy tools implemented by the Paris municipality following the COVID-19 pandemic to accelerate commercial building conversions and (2) evaluate the potential for such conversions, considering former policies. We found that adaptive reuse policies have been implemented following the beginning of the COVID-19 crisis. However, according to the collected data, conversion potential is limited, due to the continuing demand for office space despite the changes and economic considerations. © 2022 Informa UK Limited, trading as Taylor & Francis Group.

Identifying COVID-19 english informative tweets using limited labelled data

Identifying COVID-19 informative tweets is very useful in building monitoring systems to track the latest updates. Existing approaches to identify informative tweets rely on a large number of labelled tweets to achieve good performances. As labelling is an expensive and laborious process, there is a need to develop approaches that can identify COVID-19 informative tweets using limited labelled data. In this paper, we propose a simple yet novel labelled data-efficient approach that achieves the state-of-the-art (SOTA) F1-score of 91.23 on the WNUT COVID-19 dataset using just 1000 tweets (14.3% of the full training set). Our labelled data-efficient approach starts with limited labelled data, augment it using data augmentation methods and then fine-tune the model using augmented data set. It is the first work to approach the task of identifying COVID-19 English informative tweets using limited labelled data yet achieve the new SOTA performance. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.

Positive predictive value of rapid antigen tests in school during SARS-CoV-2 Omicron variant surge

In Korea, we conducted a national observational study to calculate the positive predictive value of SARS-CoV-2 rapid antigen tests in K-12 schools during the Omicron variant surge in March 2022. The weekly positive predictive value ranged from 86.4% to 93.2%. The positive predictive value was the highest among elementary school students with symptoms (95.7%) and lowest among teachers/staff without symptoms (70.9%). .

Data-informed building energy management (DiBEM) towards ultra-low energy buildings

To support building operations in reaching ultra-low energy targets, this paper proposes a data-informed building energy management (DiBEM) framework to improve energy efficiency systematically and continuously at the operation stage. Specifically, it has two key features including data-informed energy-saving potential identification and data-driven model-based energy savings evaluation. The paper demonstrates the proposed DiBEM with a detailed case study of an office and living laboratory building located in Cambridge, Massachusetts called HouseZero. It focuses on revealing the performance of the energy-efficient interventions from two-years' building performance monitoring data, as well as evaluating energy savings from the interventions based on the data-driven approach. With Year 1 as baseline, several interventions are proposed for Year 2 including improvements to controls and operation settings, encouragement of occupants' behavior for energy savings, and hardware retrofitting. These were deployed to heating/cooling, domestic hot water, lighting, plug and other loads, and photovoltaic (PV) systems. To quantify the impacts of different interventions on energy end uses, several data-driven models are developed. These models utilize linear regression, condition model, and machine learning techniques. Consequently, the heating/cooling energy consumption that was already ultra-low in Year 1 (12.8 kWh/m2) is further reduced to 9.7 kWh/m2 in Year 2, while the indoor thermal environment is well maintained. The domestic hot water energy is reduced from 2.3 kWh/m2 to 1.2 kWh/m2. The lighting energy is only increased from 0.3 kWh/m2 in pandemic operations without occupancy in Year 1 to 0.8 kWh/m2 in partial normal operations in Year 2, while the indoor illuminance level meets occupants' requirements. Combined with other relatively constant loads and the reduction of plug and other loads due to COVID building operation restrictions, the total energy use intensity is thereby reduced from 54.1 kWh/m2 to 42.8 kWh/m2, where 5.4 kWh/m2 of energy reduction for Year 2 is estimated to be contributed by the energy-efficient interventions. PV generation is 36.1 kWh/m2, with an increase of 1.4 kWh/m2 from a new inverter. In summary, this paper demonstrates the use of DiBEM through a detailed case study and long-term monitoring data as evidence to achieve ultra-low energy operations. © 2022 Elsevier B.V.

Dynamic digital capabilities and supply chain resilience: The role of government effectiveness

Organizations in recent times are increasingly investing in building supply chain resilience following disruptions due to natural disasters, geo-political crises, and pandemics. A lack of government support has exacerbated the disruption to supply chains in some regions of the world. The positive influence of digitalization on social inclusion, government accountability, and creating a more open environment is well understood. Despite this, different countries have shown varying degrees of digital responsiveness during the pandemic as they attempted to deal with the effects of various COVID strains. The influence of government policies on the supply chain has not been examined in the literature so far and, hence, to address this research gap, we examine the interaction effect of government support effectiveness i.e., tax credits, interest deferral, digital investment, soft loans on dynamic capabilities i.e., digital adaptabilities and digital agilities and on supply chain resilience, using a multi-method approach. To understand how digital adaptability and agility improve supply chain resilience, we conducted 13 semi-structured interviews. Additionally, we pretested our measurement instrument using qualitative semi-structured interviews to validate our hypothesized relationships. We collected data at a specific point of time using a survey-based instrument (N = 203) to address our research questions. Based on data analyses of both the qualitative and survey-based data, our findings indicate that digital adaptability is an important driver of digital agility. Furthermore, the results indicate that government effectiveness is crucial to enhancing supply chain resilience by enhancing digital adaptability and agility. Our research makes some useful contributions to the dynamic capability view by enhancing theoretical understanding, of the role of government in building digital capabilities in uncertain times, to improve supply chain resilience. It also bridges the research gaps between macro and micro perspectives, as identified by management scholars. Lastly, we noted the weaknesses and limitations in the study and therefore we have offered multiple research directions forward, that could help researchers to further develop our current work. © 2023 The Authors

The Teaching of Technology-Mediated Architectural Design

This work presents the strategies used in the development of the teaching of the subject of Architecture Project III of the School of Architecture and Urbanism of the Federal Fluminense University from the return to classes during the period of the Covid-19 Coronavirus pandemic which started in 2020. The course was carried out in the online teaching system mediated by technology. Considering the complexity that the teaching of architecture design requires in the fourth semester of the course, and given the conditions imposed by the pandemic, the development of technology-mediated design teaching was a challenge faced by the teachers of the subject. The teaching project theme is complex and extensive and considers a mixed-use high-rise building, with residential and commercial units in a consolidated urban environment, oriented towards the design and development of open and closed spaces, as well as public, collective and private spaces. This article covers the experiences, the strategies adopted, the difficulties and the results obtained in the teaching of architectural design from September 2020 until February 10, 2022. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Energy signature-based clustering using open data for urban building energy analysis toward carbon neutrality: A case study on electricity change under COVID-19

Under the necessity for urban energy savings and the importance of energy demand changes, this paper proposes energy analytics of urban buildings using a novel clustering method with open data. In the proposed method, the concept of energy signatures is introduced, and the signatures are defined as the representative symbols in the symbolic hierarchical clustering. This method can advance the existing clustering method or symbolic aggregate approximation (SAX) with limited energy usage patterns by introducing energy signatures with various pieces of energy information into the symbolic transformation. The proposed method can scientifically support tracking building energy usage and patterns, evaluating the existing concepts (such as green retrofitting and zero energy buildings) and advanced technologies, and the decision-making process for new policies under the global carbon neutrality scenarios. In a case study applied to a city using open energy data (in South Korea), the proposed method determined five representative clusters/areas, revealing the open data quality problems (anomaly and missing data), energy usage changes (e.g., energy usage polarization) caused by COVID-19, and the necessity of classifying building types in terms of energy usage patterns. Specifically, the cluster for decreasing energy patterns accounted for approximately 37%, and the increasing patterns accounted for 25%. Educational buildings accounted for 70% of the decreasing patterns, and technical and medical research facilities accounted for 76% of the increasing patterns under the COVID-19. Approximately 93% of missing data was found in the residential buildings. Anomaly data accounted for 10.9% in the total data.

Comparing airborne infectious aerosol exposures in sparsely occupied large spaces utilizing large-diameter ceiling fans

In sparsely occupied large industrial and commercial buildings, large-diameter ceiling fans1 (LDCFs) are commonly utilized for comfort cooling and destratification;however, a limited number of studies were conducted to guide the operation of these devices during the COVID-19 pandemic. This study conducted 223 parametrical computational-fluid-dynamics (CFD) simulations of LDCFs in the U.S. Department of Energy warehouse reference building to compare the impacts of fan operations, index-person, and worker-packing-line locations on airborne exposures to infectious aerosols under both summer and winter conditions. The steady-state airflow fields were modeled while transient exposures to particles of varying sizes (0.5–10 μm) were evaluated over an 8-h period. Both the airflow and aerosol models were validated by measurement data from the literature. It was found that it is preferable to create a breeze from LDCFs for increased airborne dilution into a sparsely occupied large warehouse, which is more similar to an outdoor scenario than a typical indoor scenario. Operation of fans at the highest feasible speed while maintaining thermal-comfort requirements consistently outperformed the other options in terms of airborne exposures. There is no substantial evidence that fan reversal is beneficial in the current large space of interest. Reversal flow direction to create upward flows at higher fan speeds generally reduced performance compared with downward flows, as there was less airflow through the fan blades at the same rotational speed. Reversing flow at lower fan speeds decreased airflow speeds and dilution in the space and, thus, increased whole-warehouse concentrations. © 2023 Elsevier Ltd

Comparison of adaptive thermal comfort with face masks in library building in Guangzhou, China

During the COVID-19 pandemic, wearing masks in public spaces has become a protective strategy. Field tests and questionnaire surveys were carried out at a university library in Guangzhou, China, during June 2021 and January 2022. The indoor environmental parameters were observed, thermal sensation votes of students on various environmental parameters were collected, symptoms of students wearing masks were quantified, and the appropriate amount of time to wear masks was established. To identify acceptable and comfortable temperature ranges, the relationship between thermal sensation and thermal index was investigated. During summer and winter, people wearing masks are symptomatic for a certain duration. The most frequently voted symptom was facial heat (62.7 % and 54.6 % during summer and winter, respectively), followed by dyspnea. During summer, more than 80 % of the participants subjects were uncomfortable and showed some symptoms after wearing masks for more than 2 h (3 h during winter). In the summer air conditioning environment in Guangzhou, the neutral Top was 26.4 °C, and the comfortable Top range was 25.1–27.7 °C. Under the natural ventilation environment in winter, the neutral Top was 20.5 °C, and the comfortable Top range was 18.5–22.5 °C. This study may provide guidance for indoor office work and learning to wear masks in Guangzhou. © 2022 Elsevier Ltd

‘Personas for lighting'. Three methods to develop personas for the indoor lighting environment

The objective of this research is to describe and compare three different methods of generating ‘persona for lighting' to envision users' behaviour within the lighting environment. ‘Personas' are used to represent typical users, highlighting their needs, perspectives, and expectations to aid user-centric design approaches. The researchers looked for the most useful method of shaping ‘personas for lighting' to learn about users' satisfaction with the various lighting conditions to identify their needs. Method one of lighting persona development, was based on interviews with 87 users of five buildings of four different types: an office, a primary school, two university buildings, and a factory. The lighting conditions were observed and measured in all the buildings. As a result, 22 personas for lighting were created. In method two personas were generated based on pre-interviews, workshops on lighting and post-interviews with ten users along with the onsite lighting measurements. Later, due to the Covid-19 pandemic's lockdowns, an online survey on the visual lighting environment in home offices was carried out among 694 students and professionals from seven countries to create two more personas for lighting (method three). All 26 ‘personas for lighting' were generated in relation to observed lighting conditions, based on the satisfaction, preferences and needs of the users working within variously lit indoor environments. All the tested methods can be used for nearly any type of building and room, but the resulting personas are different due to the specific limitations of the methods. The created personas may help to identify future users' lighting preferences, needs and requirements and assist designers. However, to fully understand their impact on the lighting research practice they should be tested in real projects. © 2022 The Author(s)

Assessment of building energy performance integrated with solar PV: Towards a net zero energy residential campus in India

Building Applied Photovoltaics (BAPV) such as Roof-top Solar PV has gained significant attention in recent years for harnessing the untapped potential of renewable energy sources. However, rooftop PV poses hurdles of space restriction and shadowing in densely packed urban residential neighborhoods. This study aims to design and assess the feasibility of an integrated grid-connected Rooftop and Façade Building Integrated Photovoltaic (BIPV) for meeting the energy demand of residential buildings on an academic campus. Three distinctive groups of residential typologies have been investigated in this study, categorized based on built area and occupants' past energy usage. Additionally, the variation in the measured Energy Performance index of the three different residential groups is illustrated to pave the path for the development of a typology-based residential energy benchmarking and labelling system. The Solar PV system has been designed for the maximum household energy demand recorded in CoVID-affected years due to high residential electricity usage in this period. The study showcases that integration of façade BIPV for low-rise residential buildings increases the system energy production to up to 62.5 % based on the utilized surface area for active PV. Furthermore, the Net Zero Energy Building (ZEB) potential for each typology has been achieved by integration of the proposed Solar PV, evaluated as a function of the Energy Performance Index (EPI) and Energy Generation Index (EGI). The designed nominal PV power of the proposed grid-connected plant is 5.6 MW, producing 7182 MWh annually, meeting the maximum residential energy demand in the studied academic campus in CoVID affected year. © 2022 Elsevier B.V.

Resilience Index Framework for the Construction Industry in Developing Countries

The construction industry in many developing countries is considered the main engine for economic growth. Quantification of the resilience of the construction industry in developing economies is essential for stakeholders and decision makers. Many researchers have attempted to quantify the construction industry's resilience in the context of developed economies;however, there is lack of established measures of such quantification in developing countries. This paper proposes a framework for the composition of an index that quantifies the resilience of the construction industry in developing countries. The proposed framework is demonstrated in the context of three developing countries: Rwanda, Egypt, and Turkey. The index is composed of measures such as the construction value added to a country's gross domestic product (GDP) and employment in construction. Principal Component Analysis (PCA) is utilized for weighting and aggregation of the individual variables. Studying the causal relationship between construction growth and economic development from 1971 to 2022, results show that construction growth leads to economic development in each of the three countries. Results of the proposed index values indicate that the construction industry in each of the three countries demonstrated increased resilience by sustaining both its outputs and its employment generation aspect in the two years following the coronavirus pandemic in 2019. Quantification of the construction industry's resilience in countries where the construction growth leads to the economic growth would provide a crucial insight for stakeholders and decision makers. © 2023 American Society of Civil Engineers.

A SIMULATION-BASED APPROACH TO MITIGATE DISEASE TRANSMISSION RISK FROM AEROSOL PARTICLES IN BUILDINGS

Understanding the role of architectural design in identifying the risk of disease transmission is essential for creating resilience in buildings. Here we used a Grasshopper simulation workflow to execute aerosol disease transmission risk estimation coupled with EnergyPlus simulation inputs to assess the impact of architectural factors on the risk of COVID-19 transmission. We simulated the risk for a simple geometry with different window configurations and geographic locations. We observed that increasing the fractional opening of a single window as well as cross ventilation design can increase the outdoor air exchange, which corresponds to substantially reduced risk of disease transmission. Furthermore, indoor relative humidity in cold climates can be significantly lower in winter due to the impacts of increased mechanical heating which translates to an increased risk of infection. We demonstrate that early architectural design decisions implicate the resultant risk of disease transmission indoors that should be prioritized in the future. © 2022 Society for Modeling & Simulation International (SCS)

Delivering a new helicopter base at Kai Tak for the Hong Kong Government Flying Service

An additional helicopter base has been built for the Government Flying Service at the former Kai Tak airport runway site in Hong Kong, China. The base allows high-rise development to take place at Tung Chung new town near the service's existing base at Hong Kong International airport, which would have restricted emergency helicopter operations during poor weather. The project involved construction of a take-off and landing pad, parking bays and hangar for two helicopters, plus an office building for the flight planning centre and air command and control centre. This paper describes how use of an NEC contract helped ensure close collaboration between the employer and contractor, leading to timely completion with zero accidents despite restrictions caused by the Covid-19 pandemic.

Experimental and numerical evaluation of a novel dual-channel windcatcher with a rotary scoop for energy-saving technology integration

With the increasing requirements for fresh air supply in buildings after the COVID-19 pandemic and the rising energy demand from buildings, there has been an increased emphasis on passive cooling techniques such as natural ventilation. While natural ventilation devices such as windcatchers can be a sustainable and low-cost solution to remove indoor pollutants and improve indoor air quality, it is not as reliable as mechanical systems. Integration with low-energy cooling, heating or heat recovery technologies is necessary for operation in unfavourable outdoor conditions. In this research, a novel dual-channel windcatcher design consisting of a rotary wind scoop and a chimney was proposed to provide a fresh air supply irrespective of the wind direction. The dual-channel design allows for passive cooling, dehumidification and heat recovery technology integration to enhance its thermal performance. In this design, the positions of the supply and return duct are "fixed” or would not change under changing wind directions. An open wind tunnel and test room were employed to experimentally evaluate the ventilation performance of the proposed windcatcher prototype. A Computational Fluid Dynamic (CFD) model was developed and validated to further evaluate the system's ventilation performance. The results confirmed that the system could supply sufficient fresh air and exhaust stale air under changing wind directions. The ventilation rate of the rotary scoop windcatcher was higher than that of a conventional 8-sided multidirectional windcatcher of the same size. © 2023 The Author(s)

THE INFLUENCE OF COVID RELATED VENTILATION RATE CHANGES ON THE ENERGY CONSUMPTION AND INFECTION PROBABILITY OF THE BUILDINGS: UNDERFLOOR AND OVERHEAD AIR DISTRIBUTION SYSTEMS

The COVID-19 pandemic has urged the need to reconsider how our built environments influence our health conditions. The new guidelines have highlighted the importance of environmental settings in the virus transmission process. Given that external air ventilation is a major element of a building's energy performance, it is necessary to investigate the influence of the new settings on the building's energy consumption. This study aims to determine the energy performance and infection risk of underfloor air distribution UFAD and overhead systems OH when exposed to varying levels of external air ventilation. The findings indicate that raising the rate of outside ventilation increases a building's energy usage in all climates. It is also shown that the UFAD system shows its energy-saving potential the most in cold climates and higher ventilation rates. These findings suggest that it is critical to consider distinct ventilation techniques to prevent rising energy consumption rates while lowering the risk of viral transmission. © 2022 Society for Modeling & Simulation International (SCS)

An international survey on residential lighting: Analysis of summer-term results.

Obtaining visual comfort, satisfaction and well-being in residential interiors are now becoming more important, especially in times of extreme events such as the COVID-19 pandemic. It also became important to collect users' evaluations and their own solutions for residential lighting in order to improve the current lighting conditions. For this aim, with a group of international and inter-disciplinary researchers, a comprehensive study was conducted. This study is the last part of a three-stage investigation aimed at increasing our knowledge of the current lighting conditions in residential areas during and after the COVID-19 pandemic. For the current study, an online survey and in-depth interviews were conducted between June and August 2022 in Poland, Turkey, Sweden, and the U.K., with 520 participants. As results of this study show, a correlation was found between daylight satisfaction and its sufficiency. Similar correlations were found between artificial lighting satisfaction, its sufficiency, and its uniformity. The differences between seasons were detected for being very satisfied with daylight quality. Also, the correlation between satisfaction with daylighting and the ratio of windows showed difference among seasons. Stronger correlations between satisfaction with artificial lighting, its sufficiency and uniformity were found in summerterm according to winter-term results. Correlations between artificial lighting brightness - CRI and uniformity weakened in summer-term. Results from open-ended questions and in-depth interviews showed, removing the shading device and augmenting the characteristics of artificial lighting were the mostly done adjustments during the COVID- 19 pandemic. The most prominent theme is visual comfort according to the in-depth interview responses.'