Correction: Babo et al. Characterization and Long-Term Stability of Historical PMMA: Impact of Additives and Acrylic Sheet Industrial Production Processes. Polymers 2020, 12, 2198

The authors wish to make a change to the published paper [...]

A Cost Benefit Analysis of Secondary Glazing as a Retrofit Alternative for New Zealand Homes

<p>Homes with single glazing represent a large majority of the New Zealand housing stock. With the recent changes to the NZ Building Code Clause H1 Energy Efficiency, new homes require higher glazing thermal performance. This will lead to an increased need for cost effective methods to improve window thermal performance in existing single glazed homes without completely replacing the windows, which includes 'secondary' glazing. There are several secondary glazing options available including 'stick-on' plastic glazing as well as aluminium framed glass solutions that are installed inside the existing joinery. Secondary glazing is marketed as a cost effective alternative to insulated glazing units, providing both improved acoustic and thermal insulation to existing windows. There is little information regarding the in-use performance and cost benefits of secondary glazing in New Zealand. This thesis explores the efficacy of the secondary glazing products when installed in existing single pane frames. A guarded hotbox was used to make thermal resistance measurements on a typical single glazed aluminium window with timber reveal liner. Four common secondary glazing systems were retrofitted into the window - (1) thin plastic film; (2) magnetically-attached acrylic sheet; (3) aluminium framed secondary glazing; and (4) aluminium framed low emissivity (low-E) secondary glazing. Models of 'typical' New Zealand homes created in the ALF building thermal simulation programme were used to explore the heating energy savings and cost benefits provided by the different secondary glazing systems in a range of locations. Of the tested products, the low-E secondary glazing produces the largest cost-benefits. At current energy and material costs, secondary glazing was found to not be a financially viable solution in warmer climates such as Auckland. In cooler climates such as Christchurch and Dunedin, secondary glazing was found to be a cost effective retrofit alternative for existing single glazed homes</p>

A Cost Benefit Analysis of Secondary Glazing as a Retrofit Alternative for New Zealand Homes

<p>Homes with single glazing represent a large majority of the New Zealand housing stock. With the recent changes to the NZ Building Code Clause H1 Energy Efficiency, new homes require higher glazing thermal performance. This will lead to an increased need for cost effective methods to improve window thermal performance in existing single glazed homes without completely replacing the windows, which includes 'secondary' glazing. There are several secondary glazing options available including 'stick-on' plastic glazing as well as aluminium framed glass solutions that are installed inside the existing joinery. Secondary glazing is marketed as a cost effective alternative to insulated glazing units, providing both improved acoustic and thermal insulation to existing windows. There is little information regarding the in-use performance and cost benefits of secondary glazing in New Zealand. This thesis explores the efficacy of the secondary glazing products when installed in existing single pane frames. A guarded hotbox was used to make thermal resistance measurements on a typical single glazed aluminium window with timber reveal liner. Four common secondary glazing systems were retrofitted into the window - (1) thin plastic film; (2) magnetically-attached acrylic sheet; (3) aluminium framed secondary glazing; and (4) aluminium framed low emissivity (low-E) secondary glazing. Models of 'typical' New Zealand homes created in the ALF building thermal simulation programme were used to explore the heating energy savings and cost benefits provided by the different secondary glazing systems in a range of locations. Of the tested products, the low-E secondary glazing produces the largest cost-benefits. At current energy and material costs, secondary glazing was found to not be a financially viable solution in warmer climates such as Auckland. In cooler climates such as Christchurch and Dunedin, secondary glazing was found to be a cost effective retrofit alternative for existing single glazed homes</p>

Application of transparent microperforated panel to acrylic partitions for desktop use: A case study by prototyping

There are various measures currently in place to prevent the spread of COVID-19; however, in some cases, these can have an adverse effect on the acoustic environment in buildings. For example, transparent acrylic partitions are often used in eating establishments, meeting rooms, offices, etc., to prevent droplet infection. However, acrylic partitions are acoustically reflective; therefore, reflected sounds may cause acoustic problems such as difficulties in conversation or the leakage of conversation. In this study, we performed a prototyping of transparent acrylic partitions to which a microperforated panel (MPP) was applied for sound absorption while maintaining transparency. The proposed partition is a triple-leaf acrylic partition with a single acrylic sheet without holes between two MPP sheets, as including a hole-free panel is important to a possible droplet penetration. The sound absorption characteristics were investigated by measuring the sound absorption in a reverberation room. As the original prototype showed sound absorption characteristics with a gentle peak and low values due to the openings on the periphery, it was modified by closing the openings of the top and sides. The sound absorption performance was improved to some extent when the top and sides were closed, although there remains the possibility of further improvement. This time, only the sound absorption characteristics were examined in the prototype experiments. The effects during actual use will be the subject of future study.

Application of transparent microperforated panel to acrylic partitions for desktop use: A case study by prototyping

There are various measures currently in place to prevent the spread of COVID-19; however, in some cases, these can have an adverse effect on the acoustic environment in buildings. For example, transparent acrylic partitions are often used in eating establishments, meeting rooms, offices, etc., to prevent droplet infection. However, acrylic partitions are acoustically reflective; therefore, reflected sounds may cause acoustic problems such as difficulties in conversation or the leakage of conversation. In this study, we performed a prototyping of transparent acrylic partitions to which a microperforated panel (MPP) was applied for sound absorption while maintaining transparency. The proposed partition is a triple-leaf acrylic partition with a single acrylic sheet without holes between two MPP sheets, as including a hole-free panel is important to a possible droplet penetration. The sound absorption characteristics were investigated by measuring the sound absorption in a reverberation room. As the original prototype showed sound absorption characteristics with a gentle peak and low values due to the openings on the periphery, it was modified by closing the openings of the top and sides. The sound absorption performance was improved to some extent when the top and sides were closed, although there remains the possibility of further improvement. This time, only the sound absorption characteristics were examined in the prototype experiments. The effects during actual use will be the subject of future study.

Application of transparent microperforated panel to acrylic partitions for desktop use: A case study by prototyping

There are various measures currently in place to prevent the spread of COVID-19; however, in some cases, these can have an adverse effect on the acoustic environment in buildings. For example, transparent acrylic partitions are often used in eating establishments, meeting rooms, offices, etc., to prevent droplet infection. However, acrylic partitions are acoustically reflective; therefore, reflected sounds may cause acoustic problems such as difficulties in conversation or the leakage of conversation. In this study, we performed a prototyping of transparent acrylic partitions to which a microperforated panel (MPP) was applied for sound absorption while maintaining transparency. The proposed partition is a triple-leaf acrylic partition with a single acrylic sheet without holes between two MPP sheets. The sound absorption characteristics were investigated by measuring the sound absorption in a reverberation room. As the original prototype showed sound absorption characteristics with a gentle peak and low values due to the openings on the periphery, it was modified by closing the openings of the top and sides. The sound absorption performance was improved to some extent when the top and sides were closed, although there remains the possibility of further improvement. This time, only the sound absorption characteristics were examined in the prototype experiments. The effects during actual use will be the subject of future study.

Changes of the Neutron Flux of the Nuclear Reactor Triga Mark III Since the Conversion from High to Low 235U Enrichment

The neutron flux of the Triga Mark III research reactor was studied using nuclear track detectors. The facility of the National Institute for Nuclear Research (ININ), operates with a new core load of 85 LEU 30/20 (Low Enriched Uranium) fuel elements. The reactor provides a neutron flux around 2 × 1012 n cm-2s-1 at the irradiation channel. In this channel, CR-39 (allyl diglycol policarbonate) Landauer® detectors were exposed to neutrons; the detectors were covered with a 3 mm acrylic sheet for (n, p) reaction. Results show a linear response between the reactor power in the range 0.1 - 7 kW, and the average nuclear track density with data reproducibility and relatively low uncertainty (±5%). The method is a simple technique, fast and reliable procedure to monitor the research reactor operating power levels.

DESIGN AND DEVELOPMENT OF MOBILE OPERATED PORTABLE VENTILATOR.

This paper describes the concept of full function portable ventilator, which have low cost, minimum weight, compact, small-sized. It can easily operate by mobile application and that application able to measure PEEP pressure, tidal volume and flow rate. The essential components used are stepper motor, rack and pinion, motor driver, Nod MCU, Acrylic sheet, Battery etc. There are some open sources Hardware ventilator (OSM-MVs) have been used during COVID-19 Pandemic. The ventilator device breaths by compressing a convention bag-valve mask (BVM) with a help of Rack and Pinion, that eliminate the need of human operator for the BVM. Initially the prototype is built out by Acrylic Sheets, it is work as thermal insulator and it's approximately 20% better than glass. The measurement of portable ventilator is 9.8*4.7*7 inches (250*120*180) mm and weighting 2.20lbs (1.5kg). It is driven by the motor driver powered by a VDC battery. The sensors are used to operate it by a mobile operation for measurement of tidal volume, PEEP pressure etc. The design is made up of CAD software and also makes Ansys for this device. The experimental results taking after testing on artificial lung that where the Positive Inspiratory Pressure (PIP), respiratory rate (RR), tidal volume, Positive end- expiratory pressure (PEEP) and its accuracy exceeding human capabilities in BVM.