Effect of Cavity Vacuum Pressure Diminution on Thermal Performance of Triple Vacuum Glazing

open access articleLong-term durability of the vacuum edge seal plays a significant part in retrofitting triple vacuum glazing (TVG) to existing buildings in achieving progress towards a zero-energy building (ZEB) target. Vacuum pressure decrement with respect to time between panes affects the thermal efficiency of TVG. This study reports a 3D finite element model, with validated mathematical methods and comparison, for the assessment of the influence of vacuum pressure diminution on the thermal transmittance (U value) of TVG. The centre-of-pane and total U values of TVG are calculated to be 0.28 Wm−2 K−1 and 0.94 Wm−2 K−1 at the cavity vacuum pressure of 0.001 Pa. The results suggest that a rise in cavity pressure from 0.001 Pa to 100 kPa increases the centre-of-pane and total U values from 0.28 Wm−2 K−1 and 0.94 Wm−2 K−1 to 2.4 Wm−2 K−1 and 2.58 Wm−2 K−1, respectively. The temperature descent on the surfaces of TVG between hot and cold sides increases by decreasing the cavity vacuum pressure from 50 kPa to 0.001 Pa. Nonevaporable getters will maintain the cavity vacuum pressure of 0.001 Pa for over 20 years of life span in the cavity of 10-mm wide edge-sealed triple vacuum glazing, and enable the long-term durability of TVG

Investigation of woven commingled thermoplastic composite for the prosthetic application

Prosthetic Sockets serve as an integral link between the amputee’s residual limb and the rest of the prosthesis. Focusing on sustainability (recycling and bio-degradable), we explore the suitability of self-reinforced(sr) PLA and PET composite as alternative materials for manufacturing prosthetic sockets. For this purpose, we performed tensile and flexural testing on commingled woven srPLA and srPET composite. The srPLA exhibits elastic-brittle response having an average failure strain of 2%. In contrast, srPET displays elastic-plastic response with average failure strain reaching up to 20%. The tensile and flexural strength of srPET is 132MPa and 72MPa, respectively. This is on par with the standard prosthetic socket materials including Glass and Carbon fibre reinforced composite with thermoset matrix. Therefore, srPET could be the realistic alternative for manufacturing sustainable prosthetic sockets. In contrast, the srPLA has inferior mechanical properties to that of standard prosthetic socket materials. Since the srPLA composite has recyclability and bio-degradability, it can be used to manufacture the test or check sockets; thus reducing the plastic pollution due to discarded check sockets

Essays on Credence Goods with Applications to Health Care and News Markets

Motivated by the economics of credence goods, this thesis advances our understanding of the economic analysis of health care and media markets. Despite fundamental differences in purpose and nature, health care and media markets share – from an economic theory perspective – a number of important commonalities. In both markets, qualified experts provide a service (treatment, news content) to their consumers (patients, audience), who are often unable to verify the service quality on their own and therefore have to rely largely on their experts’ behavior. The thesis builds on three separate research papers. The second chapter presents a novel, efficiency-based rationale for the widespread use of price and entry regulatory policies in many real-world credence goods markets. It analyzes a credence goods market where experts have social preferences and many consumers share one common expert. It shows that, if market entry of experts is endogenous, price regulation should be accompanied by entry restrictions to realize efficiency gains. The third chapter develops a novel approach to measuring attitudes of news outlets towards migration and polarization in a news market. It analyzes a unique dataset consisting of news pictures that news outlets published in their news stories on migration during the 2015-16 migration crisis in Germany. To put these news pictures into a natural perspective, pictures from ideological campaigns -- that are strongly engaged in favor of or against immigration – have been also investigated. It finds that news outlets exploit less than 50 percent of the differentiation that is used by ideological campaigns. Apart from one tabloid news outlet, it finds that news outlets maintain their relative position over time even when public sentiment about migration shifted strongly. The fourth chapter introduces a more holistic measure to evaluate a news outlet’s attitude towards migration and polarization in the market for news. Human coders from a large-scale, representative survey evaluated a large sample of pictures from Chapter 3 with respect to their degree of positivity/negativity. It finds that news outlets use approximately 60 percent of the differentiation of ideological campaigns. Again, with the exception of one tabloid outlet, it finds that news outlets maintain their relative position over time even when public sentiment about migration shifted strongly

Investigating the Problems of Letters-Based Pronunciation

Letters (alphabet) are important elements of writing and pronunciation in many languages around the world. In the English language, letters are useful only for writing, but in pronunciation, they're more problematic. There are a lot of exceptions in English spelling. The letters and their pronunciations are not fixed and do not match. This confuses foreign learners and speakers of the English language when they pronounce words based on letters. The data for this article was collected after reading and analyzing updated books and articles from reliable sources like libraries and internet sites. It is noteworthy that a descriptive-analytical method is used in this research. Since there is no research with the same title and subject, it can be interesting and useful work for those who want to study in this field. The current article discusses the problems that arise from letter-based pronunciation by considering the consequences between letters and sounds, some exceptions in letters or spelling, and inflectional morphemes

Drilling resistance: A method to investigate bone quality

Purpose: Bone drilling is a major part of orthopaedic surgery performed during the internal fixation of fractured bones. At present, information related to drilling force, drilling torque, rate of drill-bit penetration and drill-bit rotational speed is not available to orthopaedic surgeons, clinicians and researchers as bone drilling is performed manually. Methods: This study demonstrates that bone drilling force data if recorded in-vivo, during the repair of bone fractures, can provide information about the quality of the bone. To understand the variability and anisotropic behaviour of cortical bone tissue, specimens cut from three anatomic positions of pig and bovine were investigated at the same drilling speed and feed rate. Results: The experimental results showed that the drilling force does not only vary from one animal bone to another, but also vary within the same bone due to its changing microstructure. Drilling force does not give a direct indication of bone quality; therefore it has been correlated with screw pull-out force to provide a realistic estimation of the bone quality. A significantly high value of correlation (r2 = 0.93 for pig bones and r2 = 0.88 for bovine bones) between maximum drilling force and normalised screw pull-out strength was found. Conclusions: The results show that drilling data can be used to indicate bone quality during orthopaedic surgery

Development of affordable hot box calorimeter to determine the U-value of inhomogeneous building material

open access articleIn recent years, the use of three-dimensional printing to create construction components has advanced quickly; it is possible now to simplify construction, increase speed, and lower cost while using natural resources responsibly. It also allows us to use recycled material to produce building envelopes while increasing design flexibility. However, the thermal performance of building materials must be characterized to achieve the necessary energy efficiency of the building envelopes. This study aims to develop, produce, and calibrate a hot box calorimeter at a reasonable price for thermal testing components building envelope. The heat loss through these components using a hot box can be measured in a lab to get an idea of the thermal performance of the building envelopes. In order to evaluate and analyze the thermal performance of various 3D-printed building brick samples made in the labs, this study explains the design and creation of an inexpensive hot box. The hot box can conduct a conventional thermal experiment, which involves monitoring heat flux, surface temperatures, and air temperatures. The testing process, instrumentation, test conditions, and validation of the new metering box are all covered in the article. The U-value of the brand-new lattice-based 3D printed building blocks was afterward determined using the validated new hot box. It was observed that the U-values values of 1.04 W/m2.K and 0.99 W/m2.K, respectively, for small components utilizing developed hot box and larger lattice panels using commercial equipment, with a maximum variance of 5%. It highlights the dependability of the hot box apparatus, which is also made affordable to operate by using less material for specimen preparation and less energy to maintain the temperature in the hot and cold chambers. Its small size also makes setup and thermal testing of construction materials simple

Drilling resistance: a method to investigate bone quality

Purpose: Bone drilling is a major part of orthopaedic surgery performed during the internal fixation of fractured bones. At present, information related to drilling force, drilling torque, rate of drill-bit penetration and drill-bit rotational speed is not available to orthopaedic surgeons, clinicians and researchers as bone drilling is performed manually. Methods: This study demonstrates that bone drilling force data if recorded in-vivo, during the repair of bone fractures, can provide information about the quality of the bone. To understand the variability and anisotropic behaviour of cortical bone tissue, specimens cut from three anatomic positions of pig and bovine were investigated at the same drilling speed and feed rate. Results: The experimental results showed that the drilling force does not only vary from one animal bone to another, but also vary within the same bone due to its changing microstructure. Drilling force does not give a direct indication of bone quality; therefore it has been correlated with screw pull-out force to provide a realistic estimation of the bone quality. A significantly high value of correlation (r2 = 0.93 for pig bones and r2 = 0.88 for bovine bones) between maximum drilling force and normalised screw pull-out strength was found. Conclusions: The results show that drilling data can be used to indicate bone quality during orthopaedic surgery