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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]

Addressing work environment design methods has become increasingly important due to pandemic-induced changes in the ways and locations of work. This research addresses work environment design through a theory-informed workplace design framework to study the co-design process, the impact of spatial atmosphere on workplace experience and satisfaction, and infrequently studied spaces, i.e. meeting rooms and breakout areas. This case study is based on co-design methods, a workplace design intervention study and its evaluation. Comprehensive design is addressed through analytical dimensions of design, i.e. instrumental, symbolic, aesthetic and perceived dimensions of atmosphere and affordances. Furthermore, the spatial experience is explored through need-supply fit theory and workplace satisfaction. The pre-design results showed that employees have distinct design preferences based on perceived and analytical dimensions for technical, hybrid and creative meetings and individual work and recovery events. The workspace interventions were designed using the design information gathered from the co-design process; the changes implemented in intervention spaces increased employee satisfaction towards them. The study's methodology contributes to establishing a theory-informed workplace design framework supporting user-centred workplace design and evaluation and indicates a role for spatial atmosphere in need-supply fit formation. [ABSTRACT FROM AUTHOR]

Single-phase multiferroics are fractional and rarely meet at room temperature. Direct magnetoelectric coupling in relaxor ferroic phase was observed in Bi6−xPrxTi3Fe2O18 (x = 0.0, 0.3, 0.6, 0.9, and 1.2) films, where the chemical disorder doping-induced effective internal pressure played a key role. It is analytically formulated from the phase-structure shift, ferroelectric domain, and origin of the magnetic order. The strip magnetic domains are broken into a dotted domain structure following a quantitatively increase in lattice stress. A Monte Carlo simulation including stress energy items is used to unveil the hitherto unexplored coupling mechanism by tuning the symmetric exchange restriction of Fe3+–O–Fe3+. Moreover, the observation of coefficient 78.8 mV/cm·Oe at room temperature is intriguing for potential application. [ABSTRACT FROM AUTHOR]

Background An escape room is a cooperative game that has been adapted into medical education and major academic conferences. Methods We describe the design, development, and implementation of an educational ID-themed escape room activity entitled "Out-BREAK!" at an international conference, IDWeek 2023. An anonymous survey was conducted to collect demographic data, assess participant satisfaction with the escape room puzzles, and gauge participant interest in game-based learning. Results Thirty escape room sessions were held over 3 days and included 201 participants. Escape room survey respondents (n = 132) were younger and more likely to be trainees compared with in-person IDWeek attendants. Among 131 responses, all respondents enjoyed the experience and would recommend the escape room activity to friends. Survey respondents enjoyed the puzzle solving (93%), medical content (92%), and team building (79%) components. Only 35% of the respondents had ever previously participated in game-based learning; 95% thought the escape room was a valuable teaching method. Among the 72 survey respondents involved in medical education, almost all (90%) said they were interested in incorporating escape rooms into medical education. Conclusions The Out-BREAK! escape room at IDWeek 2023 was successfully implemented and well received. Despite only a third of participants having prior experience with game-based learning, almost all respondents perceived the escape room to be an effective teaching method. [ABSTRACT FROM AUTHOR]

Purpose: Meetings with colleagues are an essential activity in workplace collaboration. The iterative nature of collaborative work demands spaces that team members can access quickly and easily. Creating suitable meeting spaces will become more critical if the hybrid work model continues and the workplace environment becomes the hub for face-to-face collaborative time, learning and training. Workspace and fit-out is expensive so it is crucial that the investment in meeting spaces supports employees' collaboration activities. Design/methodology/approach: This paper presents a case study of a corporate organisation undertaken in New Zealand to investigate how employees from two business units use their workspace to collaborate within their own team and across other teams in their organisation. The study uses ethnographic techniques, including participant observation and in-depth face-to-face interviews. Findings: The findings show that the frequency and nature of small group work in collaboration was underestimated in the initial planning of the new workspace. Although participants found the design and fit-out of the formal meeting rooms supportive of collaborative work, the meeting rooms were in high demand, and it was difficult to find a room at short notice. The breakout spaces were confusing because they lacked key design attributes identified by the participants as conducive to small group work. Design shortfalls together with fit-out features perceived as supportive of collaborative work are identified. Originality/value: The research reports on employees' perceptions and experiences across two functionally diverse business units, reflecting their different needs and concerns. [ABSTRACT FROM AUTHOR]

Single‐input single‐output (SISO) three‐dimensional (3D) wideband indoor directional measurements collected in a factory environment and an office environment at 38 and 70 GHz are presented. 3D single‐input multiple‐output (SIMO) dual polarised measurements with 1 × 2 antenna configurations were also carried out in a meeting room, a conference room, and an office room at the 60 GHz band. The measurements cover both azimuth and elevation by rotating the directional antenna (RDA) at the receiver side. Different statistical channel parameters such as power delay profile, power angle profile, root‐mean‐square delay spread, angular spread, and path loss were estimated for different possible antenna orientations between the transmitter and the receiver, which include line‐of‐sight, obstructed line‐of‐sight, and non‐line‐of‐sight. The polarisation effects on path loss models and the delay and angular spread models based on the surface area of the environment are studied. The results will be valuable for the design of indoor millimetre wave cellular networks. [ABSTRACT FROM AUTHOR]

Ultra-wideband radio signals have been the subject of study for several decades. They are used to solve problems of communications and ranging. Measuring the strength (power) of a radio signal is a technically simple way to estimate the distance between the emitter and the receiver of the signal. However, the conditions of signal propagation have a significant impact on the power of the received signal. This work is relevant because chaotic radio pulses are a relatively new type of carrier in wireless technologies, and actual knowledge about the change in signal power in different types of premises is relatively small, so such a study is necessary. In this paper, we study the variation in signal power with distance for chaotic ultra-wideband radio pulses under various propagation conditions. Using experimental measurements in several outdoor (field, roadside) and indoor (corridors, conference room, office) environments, we investigate the effect of propagation conditions on ultra-wideband chaotic radio signals and determine the limits within which the dependence of the calculated power on distance can be approximated by a power law. For this purpose, the results of experimental measurements of the received signal power (a total of about 17.5 M values) were accumulated and analyzed. The accuracy of distance measurement that can be achieved in different conditions is compared and analyzed. It was found that for a 9.5 dBm signal, the range of distances at which the average accuracy is only 15–50 cm when using a power law is 5–7 m indoors and 10–15 m outdoors. [ABSTRACT FROM AUTHOR]

This study explores modern residential buildings in rural areas of Wuhan and Guangzhou to assess the feasibility of achieving net zero energy buildings (NZEBs) through the transformation of existing buildings in southern China's hot-summer–cold-winter and hot-summer–warm-winter regions. Energy simulations under various climatic scenarios identify effective energy-saving measures, such as the use of photovoltaic power generation. The results highlight substantial renovation potential, with energy reductions of approximately 85 kWh/m² (RCP2.6), 90 kWh/m² (RCP4.5), and 115 kWh/m² (RCP8.5). Living patterns significantly influence energy use, especially in buildings with more rooms, where the gaps in the energy demand with net zero standards can reach 560.56 kWh. At the monthly scale, different climate scenarios impact the feasibility of achieving NZEBs, particularly under RCP8.5, where eight rural housing types fail to meet the requirements, with six exceeding 200 kWh energy deficits and the largest energy deficit occurs in June 2090 in Guangzhou, reaching 592.53 kWh, while under RCP2.6, only two buildings with more rooms fail to meet NZE. In summary, in the hot-summer cold-winter region, the energy demand is higher but so is the solar yield. Therefore, under the most adverse RCP8.5 scenario, NZEBs are achievable for 9 months of the year, which is 2 months more compared to Guangzhou under similar conditions. Even after net zero transformation, new rural housing will face greater energy-saving challenges in future climatic conditions, especially under higher concentration pathways. [ABSTRACT FROM AUTHOR]

Virginia A. LiVolsi, a renowned figure in the field of thyroid studies, passed away on March 7, 2024. She made significant contributions to the field through her research and numerous publications, particularly in the study of papillary carcinomas and oncocytic lesions. LiVolsi was not only a dedicated researcher and author, but also a compassionate mentor to many pathologists, inspiring and nurturing their success. Her impact on thyroid pathology and her legacy continue to be felt through the work of her mentees and colleagues. [Extracted from the article]

Ensuring fairness in the utilization of government-funded public facilities, such as co-working spaces, sports fields, and meeting rooms, is imperative to accommodate all citizens. However, meeting these requirements poses a significant challenge due to the high costs associated with maintaining digital infrastructure, employee wages, and cybersecurity expenses. Fortunately, Blockchain smart contracts present an economical and secure solution for managing digital infrastructure. They offer a pay-per-transaction schema, immutable transaction records, and role-based data updates. Despite these advantages, public blockchains raise concerns about data privacy since records are publicly readable. To address this issue, this study proposes a privacy-preserving mechanism for public facilities' reservation systems. The approach involves encrypting the reservation table with fully-homomorphic encryption (FHE). By employing FHE with binary masking and polynomial evaluation, the reservation table can be updated without decrypting the data. Consequently, citizens can discreetly book facilities without revealing their identities and eliminating the risk of overlapping schedules. The proposed system allows anyone to verify reservations without disclosing requested data and table contents. Moreover, the system operates autonomously without the need for human administration, ensuring enhanced user privacy. [ABSTRACT FROM AUTHOR]

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The diversification of mobility into services such as smart stores and conference rooms has accelerated the development of purpose-built vehicles (PBVs)—vehicles designed for specific purposes that utilize an extended electric vehicle chassis and autonomous driving technology. Despite the standards on speed bump dimensions stipulated by the National Land Transportation Act of the Republic of Korea, real-world speed bumps feature varying widths and heights that deviate from these standards. In this study, a velocity equation was derived via regression analysis to achieve the desired dynamic characteristics for a PBV passing over speed bumps with varying shapes through two types of semi-active suspension control: proportional–integral–differential (PID) and linear–quadratic–regulator (LQR). For a cargo-transport PBV, the PID and LQR controllers increased the velocity by 23.74% and 50.74%, respectively, under different speed bump widths and by 19.44% and 38.31%, respectively, under different speed bump heights. Moreover, an analysis of the vibration dose value (VDV), an indicator of ride comfort, revealed that the VDVs calculated using the velocity equation were within an acceptable error range of 10% above the target VDV. These findings provide insights into the speed control required for different types of autonomous PBVs to ensure ride comfort, as well as minimize the driving duration, depending on the specific purpose of the vehicle. [ABSTRACT FROM AUTHOR]

The article shares the story about the wedding ceremony of Catherine and Anthony at Ferndale Library in Washington where Catherine works as a clerk. It considers the Ferndale Library as the safe place and attributes the decision of the couple to hold their wedding ceremony at Ferndale Library to the sense of belonging that Catherine feels in this place. Also noted is the taking of photos of the couple at the main library area after the ceremony.

As IoT technology advances, using machine learning to detect user activities emerges as a promising strategy for delivering a variety of smart services. It is essential to have access to high-quality data that also respects privacy concerns and data streams from ambient sensors in the surrounding environment meet this requirement. However, despite growing interest in research, there is a noticeable lack of datasets from ambient sensors designed for public spaces, as opposed to those for private settings. To bridge this gap, we design the DOO-RE dataset within an actual meeting room environment, equipped with three types of ambient sensors: those triggered by actuators, users, and the environment itself. This dataset is compiled from the activities of over twenty students throughout a period of four months. DOO-RE provides reliable and purpose-oriented activity data in a public setting, with activity labels verified by multiple annotators through a process of cross-validation to guarantee data integrity. DOO-RE categorizes nine different types of activities and facilitates the study of both single and group activities. We are optimistic that DOO-RE will play a significant role in advancing human activity recognition technologies, enhancing smart automation systems, and enabling the rapid setup of smart spaces through ambient sensors. [ABSTRACT FROM AUTHOR]

This article explores how sound technologies are deployed by government agencies to produce legitimacy in the struggle over oil pipelines in British Columbia, Canada. Activists seeking to stop the Northern Gateway and Trans Mountain pipelines have mobilized noise and silence as tactics of protest and refusal. For example, one thousand demonstrators make a cacophony outside a Vancouver hotel in protest of the Northern Gateway pipeline. Communications technology, though, is deployed here by the state to compress and control. In one of the hotel's small, impregnable conference rooms, public hearings over the pipeline are taking place—only the public is not allowed inside: the proceedings are being livestreamed to a hotel two kilometers away. On unceded Coast Salish territory, the legitimacy of pipeline hearings is also contested because the continued existence of Indigenous legal orders represents a challenge to the pipelines in question. Technological mediation makes it possible to satisfy one requirement of legitimacy: democratically granted representative power. The challenge to the legal system highlighted by the continued existence of the Indigenous, though, is managed through audile techniques deployed as anthropotechnologies. The implications for a politics of sound must be considered in light of sound's mediation, which is never politically neutral. [ABSTRACT FROM AUTHOR]

The current cases and studies show that the aerosol propagation of COVID-19 is possible in the office buildings. The paper explored the ventilation level and monitoring methods for indoor infection risk in office buildings, improved the Wells-Riley equation and ventilation rate equation, providing the possibility of real-time monitoring of the transmission risk of COVID-19 in office buildings. Then, the main influencing factors of the exposure risk of SARS-CoV-2, including working density, dwell time, and fresh air volume per person, were field measured in three office areas and three conference rooms of an office building in Shenzhen, China. In addition, the field monitored carbon dioxide (CO2) data were used to estimate the possibility of COVID-19 infection in offices and conference rooms. The results show that the number of staff, ventilation rate, and office hours are all important factors affecting the infection risk of workers in the office building environment, but the existing literature rarely considers these three points at the same time. In addition, the paper adopted the method of assessing the infection risk from place to place, time to time, and person to person in the building environment, providing early warning for office buildings and helping to control the spread of airborne diseases. The results can be beneicial to understanding and taking necessary safety considerations against the infection risk in closed public or governmental environments. The paper explored the ventilation level and monitoring methods for indoor infection risk in office buildings and improved the Wells-Riley equation and ventilation rate equation, providing the possibility of real-time monitoring of the transmission risk of COVID-19 in office buildings. The results showed that the number of staff, ventilation rate, and office hours are all important factors affecting the infection risk of workers in the office building environment, but the existing literature has rarely considered these three points at the same time. Meanwhile, research has further demonstrated the connection between the risk of virus infection and indoor monitoring environmental indicators, providing a new path for further accurate prediction of indoor infection risk. The results can be beneficial to understanding and taking necessary safety considerations against the infection risk in closed public or governmental environments. Therefore, evaluating indoor transmission risks through monitoring environmental indicators is feasible and could be used as a reference basis for practical applications. [ABSTRACT FROM AUTHOR]

Unquestioned vicious identifications with dubious (e.g. political) figures seem central in today's multiple crises. As in former dark times, when M. Klein described the dynamics triggered by an 'inner Hitler', the approach offered in this contribution is to explore present forms, which we meet in the consulting room. As will be shown, a crucial step in this process lies in working through those challenges in the countertranserence. [ABSTRACT FROM AUTHOR]

Space sharing services like vacation rentals and meeting rooms are being equipped with smart devices such as cameras, door locks and many other sensors. However, the sharing of such devices poses privacy and security problems, as there is typically no clear control transfer between owners and users. In this article, we propose Spacelord, a system to time-share smart devices contained in a shared space privately and securely while allowing users to configure them. When a user stays at a space, Spacelord ensures that the smart devices contained in it run code and configurations the user trusts while removing pre-installed code and configurations. When the user leaves the space, Spacelord reverts any changes the user has introduced to the smart devices, deletes any remaining private data and lets the owner take back control over the devices. We evaluate Spacelord for two realistic space-sharing cases—smart home and coworking meeting room—and observe smart space provisioning delays of ~82sacross three different platforms. Moreover, the average runtime overhead of our system varies from 7.8% to 11.8% across different hub hardware, running native applications. [ABSTRACT FROM AUTHOR]

The current paper included studying the effects of soft storey locations on dynamic response of reinforced concrete (RC) buildings under the impacts of earthquakes. Soft storey is essential to provide the building with a functional space such as vehicle garages or open meeting rooms. Further analytical investigation was necessary to understand the impact of these flexible floors on the building's response during earthquakes, as conducting experimental research to address this issue is highly difficult. The research encompassed the effects of soft storey location in two types of buildings, one with equal spans and the other with unequal spans, on the nonlinear time history response. Each building consists of a 10-stories (G+9) RC residential structure subjected to earthquake effects. The analysis was carried out using program sap2000 v23. An analogous diagonal strut was used to illustrate the infill panels. The study included the effect of soft storeys on the natural period, the change in base shear with time, and the change of displacement and acceleration along time for each building. The obtained results showed that including a soft storey in the analysis for buildings having either equal or unequal spans increased the time period, displacement, and storey drift, causing a decrease in the acceleration and base shear forces. Building with the soft storey on the fifth floor (at the mid-height of the building) showed a better dynamic response compared with that using the soft storey on the ground and last floors. [ABSTRACT FROM AUTHOR]

The acoustic quality of learning spaces, such as classrooms, is a worldwide issue. Some countries have regulations or guidelines for these environments, which does not happen properly in Brazil. Beyond the lack of nationwide research related to classroom acoustics, Brazil has two standards with a few information related to classroom acoustics. One of them was written in 1992, having a single demand concerning an appropriate reverberation time for conference rooms at the 500 Hz frequency, without detailed requirement, in contrast to other national guidelines. Another one, updated in 2020, recommends the sound pressure levels for indoor environments, having classrooms in its list. The aim of this study is to analyze the acoustic quality of two Brazilian classrooms over a public university in the south part of Brazil. Several impulse responses were taken within the learning environments and then processed in Matlab with the ITA ToolBox. The classrooms were also modeled into RAVEN and I-SIMPA software aiming to identify different sound absorption schemes to improve their speech intelligibility. The findings showed that the classrooms had a bad acoustic environment, with a measured reverberation time of approximately 1. 60 s. However, the simulation suggested that implementing sound absorption strategies could reduce the reverberation effects by half, bringing it closer to optimal levels. The estimated costs for implementing sound absorbers were U S $ 7 , 500. 00 for Classroom 01 and U S $ 7 , 100. 00 for Classroom 02. [ABSTRACT FROM AUTHOR]

In environments where silent communication is essential, such as libraries and conference rooms, the need for a discreet means of interaction is paramount. Here, we present a single-electrode, contact-separated triboelectric nanogenerator (CS-TENG) characterized by robust high-frequency sensing capabilities and long-term stability. Integrating this TENG onto the inner surface of a mask allows for the capture of conversational speech signals through airflow vibrations, generating a comprehensive dataset. Employing advanced signal processing techniques, including short-time Fourier transform (STFT), Mel-frequency cepstral coefficients (MFCC), and deep learning neural networks, facilitates the accurate identification of speaker content and verification of their identity. The accuracy rates for each category of vocabulary and identity recognition exceed 92% and 90%, respectively. This system represents a pivotal advancement in facilitating secure and efficient unobtrusive communication in quiet settings, with promising implications for smart home applications, virtual assistant technology, and potential deployment in security and confidentiality-sensitive contexts. [ABSTRACT FROM AUTHOR]

Appropriating the dramatic genre, whose procedures are cited in the body of the text, this article reflects on some of the aspects involved in the teaching of literature in contemporary Brazilian universities. In a five-act sequence --each act referring to a different space in the university environment (the classroom, the meeting room, etc.)--, this paper explores different notions of learning and teaching, comments on responses to recent changes in the corpus and university bodies in Brazil, considers the relationship between the endogenous tradition of Brazilian patriarchal culture and immunitarian policies, and reflects on the complexity of the notion of heritage, in dialogue with the specters that haunt both Hamlet and the institutions where literature is taught. Throughout the text, I seek to highlight the materiality of daily life at university. [ABSTRACT FROM AUTHOR]

Though we spend a significant amount of time in indoor and built environments as general occupants of residential or commercial spaces, we do not necessarily know how the heating, cooling, and ventilation services work in our occupied spaces. As the mechanical systems of buildings become more complex for energy saving and better indoor air quality, it is beneficial for occupants to learn more their built environment so that they can cooperate effectively for the building's performance. In this context, the purpose of this research is to develop and evaluate how virtual reality (VR) technology can support occupants in understanding their built environment. An educational building on campus was selected for the development as it provides familiar spaces for potential participants in this research. This research was carried out in two stages. In Stage One, we, as researchers in mechanical engineering, explored the workflow for VR development and developed VR tours for four spaces: a classroom, an auditorium, a conference room, and a mechanical room. In Stage Two, we conducted a survey study to examine the VR experience from the perspective of users. In this survey study, we recruited 34 participants from engineering students/graduates, industry participants, and a sustainability group. The participants generally indicated a positive experience with the VR tours, although the quiz scores on the VR content were weak. From our reflection, we consider that positive and effective VR experiences for the education of the built environment require collaboration from three domains: (1) mechanical systems of buildings, (2) VR technology, and (3) pedagogy. [ABSTRACT FROM AUTHOR]

In industrial applications, local exhaust systems have been used extensively for capturing and confining contaminants at their source. The present study investigates the efficacy of these systems in mitigating the spread of exhaled pollutants by combining them with mixing and displacement ventilation. Experiments were conducted in a simulated meeting room with six closely situated workstations, featuring five exposed persons (simulated with heated dummies) and one infected person (simulated with a breathing manikin). Six overhead local exhaust units, merged with panels, corresponding to workstations, were installed using a lowered false ceiling. Additionally, a table plenum setting for air inlets was introduced to enhance displacement ventilation effectiveness along with local exhaust systems. Results from 16 experimental cases are presented, using the local air quality index and ventilation effectiveness in the breathing zone. The local exhaust system improved the local air quality at the measuring locations closest to the infector in almost all test scenarios. The improvement, particularly significant with displacement ventilation, marked a maximum 35% increase in the local air quality index adjacent to the infector and 25% in the entire breathing zone of the tested meeting room. Moreover, the table plenum settings, coupled with displacement ventilation, further enhanced conditions in the breathing zone. Under the specific conditions of this investigation, the number of operational local exhausts had a marginal impact on mixing ventilation but a significant one on displacement ventilation tests. The efficacy of local exhaust systems was also influenced by the levels of heat gains present in the room. Overall, the study aims to contribute to ongoing efforts to identify sustainable solutions to mitigate indoor airborne diseases with a combination of supply and local exhaust units. [ABSTRACT FROM AUTHOR]

Ubiquitous computing aims to seamlessly integrate computing into our daily lives, and requires reliable information on human activities and state for various applications. In this paper, we propose a device-free human activity recognition system that leverages the rich information behind WiFi signals to detect human activities in indoor environments, including walking, sitting, and standing. The key idea of our system is to use the dynamic features of activities, which we carefully examine and analyze through the characteristics of channel state information. We evaluate the impact of location changes on WiFi signal distribution for different activities and design an activity detection system that employs signal processing techniques to extract discriminative features from wireless signals in the frequency and temporal domains. We implement our system on a single off-the-shelf WiFi device connecting to a commercial wireless access point and evaluate it in laboratory and conference room environments. Our experiments demonstrate the feasibility of using WiFi signals for device-free human activity recognition, which could provide a practical and non-intrusive solution for indoor monitoring and ubiquitous computing applications. [ABSTRACT FROM AUTHOR]