Dynamic Insulation Systems to Control Airborne Transmission of Viruses in Classrooms: A Review of 'Airhouse' Concept

The discovery of the Covid-19 virus in China at the end of 2019 has drastically altered the global landscape. The virus, which has now become a pandemic, has wrought devastation on the world, infecting over 500 million people and killing over 6 million. The virus's mutation into a few variations, however, has enabled the world's alarming situation to continue until now. Airborne particles and viruses including the new Covid-19 variant -Omricon, is not only extremely contagious but also can be transferred by airborne transmission, putting vulnerable people like children at risk, particularly in classrooms. Amongst the strategies to control airborne transmission of viruses and to improve indoor thermal and air quality is using ventilation strategies -such as dynamic insulation. Thus, this paper will review at how dynamic insulation systems in conventional farming and residential buildings, cleanrooms and other controlled environments work to reduce airborne viruses and particles in a room. An innovative "Airhouse" concept that combines with activated carbon has been researched and investigated with regard to the dynamic insulation systems.This system has a high potential to reduce the air temperature, humidity, and airborne viruses including Covid-19 whilst maintaining a steady airflow rate in a normal room. Therefore, it has a great deal of potential to decrease or eliminate concerns about the transmission of airborne viruses and adapt ventilation systems to new pandemic threats.

Properties of composites based on recycled polypropylene and lignocellulosic agricultural waste

In the present work, composites based on recycled polypropylene (PPr) and 30% treated and untreated lignocellulosic waste were prepared. The recycled polypropylene comes from recovered surgical masks used during the COVID-19 pandemic, from which the elastic band and the metal strip have been removed. The lignocellulosic waste used as a reinforcing agent consisted of the depleted substrate from the culture of Pleurotus ostreatus fungi, being a sawdust enriched in chitin pellets of corn cobs treated with borhot from the brewing of beer. The composites with 30% of treated/untreated sawdust were obtained in dynamical conditions by melt processing. The effects of sawdust, both treated and untreated, on tensile properties (strength and modulus of elasticity), dynamic-mechanical properties (storage/loss modulus and loss factor), thermal conductivity and thermal stability were studied. The results showed improved thermal and mechanical properties of bio-composite materials based on recycled polypropylene from used face masks and sawdust, which can be used as construction materials. © 2023, Fundatia Serban Solacolu. All rights reserved.

Evaluating the technological properties of fired clay bricks incorporated with palm kernel shell

Stepping up the extraction of valuable resources from the oil palm agro-industry was fraught with palm kernel shell (PKS) disposal challenges. One mitigating measure was to recover these materials for use in fired brick production. So PKS and clay materials were characterized for their physical, mineral and thermal properties. These characterizations revealed the high content of SiO2 and Al2O3 in the clay resources and the 95.60% organic content of PKS along with its estimated 21, 774.94 (kJ/kg) higher heating value (HHV). Indexed minerals from X-ray diffraction (XRD) studies of the clay material were kaolinite, quartz, calcite and goethite. Bricks prepared with the inclusion of up to 16 wt% PKS were fired at 900 and 1000 °C. For bricks fired at 1000 °C, bulk densities decreased from 2.07 to 1.54 g/cm3, apparent porosity increased up to 89.14%, water absorption increased from 100% in reference bricks to 203.54% with the addition of 16 wt% PKS. While compressive strengths decreases were in the range of 21.67–6.07 MPa, thermal insulation improved by 22%. Similar trends were established for bricks fired at 900 °C. The analyses showed that PKS addition was more effective in tailoring the technical properties of the bricks than changes in firing temperature. The marginal differences in technical properties of bricks fired at 1000 °C relative to the 900 °C fired brick units were understood from scanning electron microscopy (SEM) studies. Therefore, this research has provided compelling evidences for use of PKS in fired brick production. © 2023 Elsevier Ltd

News From Japan

In today's international society, a vast amount of information that no one could have imagined a while ago is circulating in the world. This trend is expected to be further accelerated in the "new normal” life with COVID-19, where online social activities have become commonplace. Although organic polymers are also used for short-distance in-equipment information-transmission optical fibers, only amorphous silica (SiO 2 ) is used for long distances. In other words, what supports the information society is the insulating material familiar to readers of this IEEE Electrical Insulation Magazine.

Optimization of Building Envelope in Terms of Sound Insulation and Thermal Performance-Case Study: Antalya 100.Yil Boulevard

The most important point to be considered in terms of ‘sustainability' and ‘energy conservation' in a building is the design of the building envelope. Although the importance of thermal and sound insulation in the envelope has increased in Turkey, various problems are experienced due to regulations that have not been strictly implemented. In particular, the fact that people spend most of their time at home due to the COVID 19 pandemic has increased the importance of indoor comfort conditions. In order to increase user comfort, the first thing to do is to take the necessary measures for sound and thermal insulation, which have different physical working principles and parameters on the facades of existing buildings. It is important to design optimal facades that will meet the needs of both types of insulation. In this study, the existing building stocks that emerged as a result of the deficiencies in the zoning plans within the settlement pattern of Antalya 100. Yıl Boulevard are examined. Necessary improvement suggestions are presented in order to increase the performance, depending on the envelope. Within the scope of the study, both insulation performances of the facades are compared and solutions for the optimal envelope design were revealed. © 2022, TUBITAK. All rights reserved.

Natural ventilation as a healthy habit during the first wave of the COVID-19 pandemic: An analysis of the frequency of window opening in Spanish homes

Since SARS-CoV-2 spread worldwide in early 2020, many countries established lockdowns for protection. With a main transmission by aerosols, ventilation was promoted. This article analyses natural ventilation of Spanish housing during the spring 2020. An online questionnaire was launched, obtaining for this study 1502 responses. The comparative window opening before and during confinement, and households, dwellings and home activity variables, were analysed. The binary logistic regression model before pandemic indicated that ventilating properly related to: a worse perceived IAQ (OR = 1.56);thermal adaptation measures, especially those that prefer to open/close windows (OR = 1.45);not having heating system (OR = 1.15);and using power to heat water (OR = 1.60). For the confinement period, the model highlighted: being an employee (OR = 1.88);using heavy clothing in the home (OR = 2.36);and again, open/close windows for adaptation (OR = 2.24). According to specific tasks in quarantine, frequent ventilation was boosted by: an increasing use of oven (OR = 14.81);and alteration of work-habits (OR = 2.70), sport-habits (OR = 1.79), and outdoor-activities (OR = 1.60). Thus, an adequate natural ventilation pattern during the quarantine was linked to low environmental comfort in general, by virtue of indoor air quality. This is corroborated by less acoustic-thermal insulation, worse indicators of heating use, and the adaptive response to opening/closing windows when external temperature changed. © 2022 The Authors

A critique on the UK's net zero strategy

Before the Covid-19 pandemic UK passed net-zero emission law legislation to become the first major economy in the world to end its contribution to global warming by 2050. Following the UK's legislation to reach net-zero emissions, a long-term strategy for transition to a net-zero target was published in 2021. The strategy is a technology-led and with a top-down approach. The intention is to reach the target over the next three decades. The document targets seven sectors to reduce emissions and include a wide range of policies and innovations for decarbonization. This paper aims to accomplish a much needed review of the strategy in heat and buildings part and cover the key related areas in future buildings standard, heat pumps and use of hydrogen as elaborated in the strategy. For that purpose, this research reviews key themes in the policy, challenges, recent advancement and future possibilities. It provides an insight on the overall development toward sustainability and decarbonization of built environment in the UK by 2050. A foresight model, Future Wheels is also used to visualize the findings from the review and provide a clear picture of the potential impact of the policy. © 2023

Just noticeable difference of loudness through building wall of masonry and drywall

In this study, the just noticeable difference (JND) of loudness with respect to sound transmission through walls corresponding to a weighted noise reduction index R-w of 43 dB is investigated. Two types of walls typically used in Argentina are evaluated. One is masonry composed of solid autoclaved aerated concrete bricks with a thickness of 25 cm, and the other is a drywall composed of two 12.5 mm plasterboards with a 25 cm air chamber in between them, filled with glass wool. The JND is determined using the method of constant stimuli for both ascending and descending variations. The source signals used are two types of vacuum-cleaner sounds and two music signals. Online tests are conducted owing to restrictions imposed by the COVID-19, and the presentation level of the stimuli is adjusted based on the sensation level of each individual. Responses from 148 different listeners show no significant difference in the subjective responses among the source signals. Regarding the masonry, the JND values are 3.02 and 1.62 cm for the ascending and descending variations, respectively (corresponding R-w difference of 2 and 1 dB), whereas they are 4.55 and 1.26 cm for the drywall, respectively (1 dB for both).

Real-time monitoring of food price policy interventions during the first two years of COVID-19.

COVID-19 has resulted in a shock to agrifood systems around the world, with the potential for low- and middle-income countries to be particularly affected. Although policy responses were more muted than during the 2007-2008 world food crisis, efforts to insulate from supply shocks and ensure local availability during COVID-19 have generally included export restrictions and import tariff reductions, among other responses. In an effort to enable rapid market monitoring and realignment, we develop a new indicator defined as a monthly nominal rate of protection "express" which seeks to indicate how policies enacted are affecting prices domestically in real-time in order to understand how they responded. This analysis examines changes to this indicator during the first two years of the pandemic in 24 low- and middle-income countries for the most-consumed staple cereals of the poor and food insecure. We show that gaps between domestic and international prices declined by a median of 20.3 percentage points compared to the same months in recent previous years. While policies were enacted to mitigate price increases that would have eventually been transmitted to poor consumers, other factors related to international demand and supply chain disruptions may also have contributed to the observed trend in the analyzed countries. Moreover, impacts on prices varied across countries and commodities, depending on region, net trade, and previous gap levels. Finally, this indicator can contribute to examining primary drivers of changes and conducting causal analysis to facilitate adequate agrifood policy responses to support economic recovery in the post-COVID-19 era.

Environmental evaluation of a prefab construction method employed to build the Evandro Chagas National Institute of Infectious Diseases

As a result of the global pandemic of Covid-19, there was a need to adjust to the sanitary tragedy that occurred during this time, which stimulated the construction of emergency support units to support the existing health system. In the study presented in this paper, the authors evaluate the potential environmental impacts of modular typologies through quantification and analysis of carbon emissions of a typical hospitalar module throughout its life cycle. A systematic Life Cycle Assessment analysis was carried out to quantify GHG emissions related to the construction of a module of the Evandro Chagas National Institute of Infectious Diseases in Brazil and understand the benefits of reuse and recycling processes by comparing a single-use scenario to a cradle-to-cradle approach. Another objective is to compare Polyisocyanurate (PIR), Expanded Polystyrene (EPS) and Rock wool when used as insulation, given that their thermal performance is similar but their density influences the impact rates. Overall, EPS panels present a better environmental performance while maintaining thermal comfort standards found in comparison to rock wool and PIR boards. Lastly, concrete for the slab was responsible for the highest emission rates of kg CO2eq/module year, followed by the rigid PIR foam and steel in the production and sanitary landfill disposal stages.

The impacts of price insulation on world wheat markets during the 2022 food price crisis

This paper begins with a survey of recent commodity price developments that highlights the magnitude of this price surge and identifies the rapid rise in wheat prices as a key element. The analysis in this paper focuses on the extent to which domestic markets are insulated from these changes and on the resulting impacts on world prices. An econometric analysis using error-correction models finds stable long-term relationships between world wheat prices and most domestic prices of wheat and wheat products, but with considerable variation across countries in the rate of price transmission. A case study of the price shocks during the COVID-19 pandemic and the Ukraine food price crisis finds that price insulation roughly doubled the overall increase in world wheat prices and raised their volatility both during periods of price increase and price decline.

Guest Editorial Special Issue on Electrical Discharges in Vacuum

This Special Issue contains the expanded version of selected papers presented at the 29th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV). The Symposium was scheduled to take place in June 2020 in Padua, Italy, but due to the Covid-19 pandemic, it was held on September 26–30, 2021, in virtual mode. The Symposium was hosted by the Consorzio RFX, Padua, which is a research infrastructure whose mission is the research on fusion science, implemented through the participation to the European Fusion Program, through the development and exploitation of RFX—the largest Reversed Field Pinch Fusion machine—and through the development and exploitation of the Neutral Beam Test Facility (NBTF)—the prototype of the Neutral Beam Injectors for ITER. Members of the Consorzio RFX are the Italian National Research Council (CNR), the National Agency for Energy and Sustainable Development (ENEA), the National Institute on Nuclear Physics (INFN), and Padova University. The Conference was attended remotely by 167 participants from 17 different countries.

Surface Coating of Needle-Punched Nonwovens with Meltblown Nonwovens to Improve Acoustic Properties

Unlike the term sound insulation, which means reducing the penetration of noise into other areas, sound absorption means reducing the reflection and energy of the sound on the surface. It has become a highly noticed issue in recent years because the noise in our daily life is increasing day by day, and it causes some health and comfort disorders. In many areas, textiles have been used for acoustics control and noise absorption purposes. The purpose of this work is to determine the most effective media for sound absorption performance and its relation to thermal conductivity from needle-punched nonwoven, meltblown nonwoven and hybrid forms in different arrangements of these fabrics. To provide comparable samples, both needle-punched nonwoven and meltblown nonwoven samples were produced from 100% Polypropylene fibres. According to sound absorption tests, the hybrid-structured sample having a composition similar to the needle-punched nonwoven sample placed at the bottom of our study, while the meltblown nonwoven sample placed as a face layer outperformed the rest of the samples in terms of sound absorption and thermal conductivity. ‘Meltblown only’ samples had remarkably higher sound absorption efficiency than most of the samples, while the ‘needle-punched nonwoven only’ sample had the lowest sound absorption efficiency in all frequencies.

A Guideline for Developing Resilient Office Buildings using Nanotechnology Applications

Resilient buildings have become a widely researched topic in the engineering discipline. A building has enabled connectivity between building systems, including air conditioning, ventilation, safety and security system. They are even more important with growing pandemic risks and the spread of airborne viruses such as Covid-19. The literature indicates that nanotechnology applications can have a great role in the designing resilient office buildings. Nanotechnologies play a major role in architectural design;building materials combined with nanotechnology became smaller, lighter, and more efficient than conventional materials. Thus, this research aims to develop design guidelines for resilient office buildings in Egypt using nanotechnology applications. The methodology applied includes a review on nanotechnology and resilient office buildings key design features, following a simulation using design builder program where conducted to modify the nanomaterials in resilient office buildings recorded through quantified data. After applying the nanotechnology concept on walls, the roof and glazing types by inserting nanomaterials. The research concluded that the use of vacuum insulation panel, Nano-gel glass and Nano-painting had the highest impact on decreasing the total energy consumption by 14.5% and carbon dioxide emissions by 42%.

Simulation and analysis of different heating method for bio-digester substrate

This report is on topic of simulation and analysis of different heating method for bio-digester substrate. Now-a-days the energy demand is increasing so we have to look other options and devise a method to optimize the production from other sources. Due to Covid-19 mass migration and increased hospital admission occurs, to fulfill the food supply biogas is sought. This report focus on digesters on a small scale that can be employed for household activities. To increase the biogas yield among different influencing factors temperature is chosen and worked upon. Along with insulation there is a heating method installed to maintain the stable temperature which facilitates breakdown of organic materials and improve the productivity. In colder climates maintaining mesophilic temperature can be a challenge, therefore three heating methods are simulated and analyzed. The study reveals about floor heating, in-vessel heating and floor + in-vessel heating method. In-vessel heating method provides uniform cooling, whereas floor heating can be applied at relatively cold climates because it give significant temperature rise (about ∼14 °C). Out of these three methods floor + in-vessel heating method is found suitable as it optimize the benefits of both floor and in-vessel heating methods with 5 °C temperature raise. © 2022

Techno-economic assessment of manufacturing process in small scale industry to evaluate energy saving potential

Energy is an essential input for smooth functioning of manufacturing industry. Small scale industries employ a significant portion of unskilled labor in India. With ever increasing competition, these industries are forced to reduce their production cost. However, these industries lack the adequate expertise about monitoring the energy usage and consequently derive the benefits of reduction in energy consumption on production cost. Cost reduction through energy saving avenues becomes particularly important after facing the impact of COVID-19 pandemic on survival and growth of such industries. This paper aims to provide a practical, grass root level perspective about utilization of energy audit as an effective energy conservation tool. This tool gives the plant management a factual idea about technical and economic feasibility of various Energy Conservation Measures (ECMs) suggested, in quantitative terms. This paper puts forth the outcomes of energy audit conducted in a small-scale industry engaged in the manufacturing of non – ferrous flat and shape wires, high precision rolling mills, slab caster etc. Energy audit was focused on energy savings in electrical as well as thermal systems. Energy audit study revealed that this small scale manufacturing plant can save 6226 kW h of electrical energy per annum, which is total saving potential of 22.82% of the plant's annual energy consumption. Suggested ECMs exhibit an average payback period of 4 months which is considerably good. © 2022

Optimal Balance between Heating, Cooling and Environmental Impacts: A Method for Appropriate Assessment of Building Envelope’s U-Value

In Europe, the recent application of regulations oriented to zero-energy buildings and climate neutrality in 2050 has led to a reduction in energy consumption for heating and cooling in the construction sector. The thermal insulation of the building envelope plays a key role in this process and the requirements about the maximum allowable thermal transmittance are defined by country-specific guidelines. Typically, high insulation values provide low energy consumption for heating;however, they may also entail a risk of overheating in summer period and thus negatively affect the overall performance of the building. In addition, the embodied energy and related emissions caused by the manufacturing and transportation processes of thermal insulation cannot be further neglected in the evaluation of the best optimal solution. Therefore, this paper aims to evaluate the influence in terms of embodied and operational energy of various walls’ thermal insulation thicknesses on residential buildings in Europe. To this end, the EnergyPlus engine was used for the energy simulation within the Ladybug and Honeybee tools, by parametrically conducting multiple iterations;53 variations of external wall U-value, considering high- and low-thermal-mass scenarios, were simulated for 100 representative cities of the European context, using a typical multifamily building as a reference. The results demonstrate that massive walls generally perform better than lightweight structures and the best solution in terms of energy varies according to each climate. Accordingly, the wall’s thermal transmittance for the samples of Oslo, Bordeaux, Rome and Almeria representative of the Continental, oceanic temperate, Mediterranean, and hot, semi-arid climates were, respectively: 0.12, 0.26, 0.42, and 0.64 W/m2K. The optimal solutions are graphically reported on the map of Europe according to specific climatic features, providing a guidance for new constructions and building retrofit.

A simulation study of the impact of the COVID-19 crisis on the energy demand of a building located in a semi-arid climate in Morocco

The COVID-19 epidemic increases the uncertainty of energy demand. This paper aims to study the impact of containment measures due to the COVID-19 epidemic on the energy demand of a group of buildings in a neighborhood and evaluate the different techniques studied on thermal performance and energy savings. Indeed, this study shows the importance of using natural and recycled waste-based materials and nighttime radiative cooling during the summer period. For this purpose, a full-scale cell located in Casablanca was considered a case study to build a simulation model performed on TRNSYS, validated using the experimental results. This model is then used to impact the techniques studied on energy performance and hours of discomfort inside another cell in Marrakech. As a result, this study has shown that the passive techniques integrated into the cell, using the material based on sisal/wool nonwoven, and night-time radiative cooling during summer, reduce energy requirements compared to the reference configuration. © 2022 IEEE.

Thermo-Energy Performance of Lightweight Steel Framed Constructions: A Case Study

The building sector continues to play an essential role in reducing worldwide energy consumption. The reduced consumption is accompanied by stricter regulation for the thermotechnical design of the building envelope. The redefined nearly Zero Energy Building levels that will come into force for each member state will pressure designers to rethink the constructive details so that mandatory levels can be reached, without increasing the construction costs over an optimum level but at the same time reducing greenhouse gas emissions. The paper aims to illustrate the main conclusions obtained in assessing the thermo-energy performance of a steel-framed building representing a holistically designed modular laboratory located in a moderate continental temperate climate, characteristic of the south-eastern part of the Pannonian Depression with some sub-Mediterranean influences. An extensive numerical simulation of the main junctions was performed. The thermal performance was established in terms of the main parameters, the adjusted thermal resistances and global thermal insulation coefficient. Further on, the energy consumption for heating was established, and the associated energy rating was in compliance with the Romanian regulations. A parametric study was done to illustrate the energy performance of the investigated case in the five representative climatic zones from Romania. An important conclusion of the research indicates that an emphasis must be placed on the thermotechnical design of Light Steel Framed solutions against increased thermal bridge areas caused by the steel’s high thermal conductivity for all building components to reach nZEB levels. Nevertheless, the results indicate an exemplary behaviour compared to classical solutions, but at the same time, the need for an iterative redesign so that all thermo-energy performance indicators are achieved.

Understanding Sustainability of Construction Products: Answers from Investors, Contractors, and Sellers of Building Materials

Preventing environmental degradation and climate changes are some of the primary challenges of our civilization. Changes to the construction sector, which consumes vast amounts of raw materials, emits significant amounts of greenhouse gas and significant amounts of waste, are very important to reduce emissions and stop negative environmental changes. Regardless of the type of goal, an essential element to achieve it is understanding the purpose and tools necessary to implement appropriate and efficient solutions. This paper presents the survey results on understanding issues related to assessing construction products, including their environmental impact. The survey was conducted among professional groups related to construction, i.e., 181 investors, 522 contractors, and 116 sellers of construction products from various regions of Poland. Questions concerning thermal insulation materials and the external thermal insulation composite system (ETICS), the most widely used solution in the EU for the improvement of thermal performance of buildings, were asked. The obtained results indicate that the knowledge of the basic requirements of construction works under the Construction Products Regulation (CPR) is not too high (the share of correct answers was respectively 33.5%, 23.2%, and 16.2% in contractors, sellers, and investors groups). Similarly, the awareness of the tested, related to the environmental burden in terms of GWP of insulation materials and components of ETICS, should be assessed (49.7% of investors, 57.1% sellers of construction products, and 76.4% contractors indicated the thermal insulation material as the ETICS component with the highest environmental impact in terms of GWP). The obtained research results indicate the need for further education for evaluating construction products and sustainability.