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Indiana University-Purdue University Indianapolis (IUPUI) / Compressed air is a powerful source of stored energy and is used in a variety of applications varying from painting to pressing, making it a versatile tool for manufacturers. Due to the high cost and energy consumption associated with producing compressed air and it’s use within industrial manufacturing, it is often referred to as a fourth utility behind electricity, natural gas, and water. This is the reason why air compressors and associated equipment are often the focus for improvements in the eyes of manufacturing plant managers. As compressed air can be used in multiple ways, the methods used to extract and transfer the energy from this source vary as well. Compressed air can flow through different types of piping, such as aluminum, Polyvinyl Chloride (PVC), rubber, etc. with varying hydraulic diameters, and through different fittings such as 90-degree elbows, T-junctions, valves, etc. which can cause one of the major concerns related to managing the energy consumption of an air compressor, and that is the waste of air through leaks. Air leaks make up a considerable portion of the energy that is wasted in a compressed air system, as they cause a multitude of problems that the compressor will have to make up for to maintain the steady operation of the pneumatic devices on the manufacturing floor that rely on compressed air for their application. When air leaks are formed within the compressed air piping network, they act as continuous consumers and cause not only the siphoning off of said compressed air, put also reduce the pressure that is needed within the pipes. The air compressors will have to work harder to compensate for the losses in the pressure and the amount of air itself, causing an overconsumption of energy and power. Overworking the air compressor also causes the internal equipment to be stretched beyond its capabilities, especially if they are already running at full loads, reducing their total lifespans considerably. In addition, if there are multiple leaks close to the pneumatic devices on the manufacturing floor, the immediate loss in pressure and air can cause the devices to operate inefficiently and thus cause a reduction in production. This will all cumulatively impact the manufacturer considerably when it comes to energy consumption and profits. There are multiple methods of air leak detection and accounting that currently exist so as to understand their impact on the compressed air systems. The methods are usually conducted when the air compressors are running but during the time when there is no, or minimal, active consumption of the air by the pneumatic devices on the manufacturing floor. This time period is usually called non-production hours and generally occur during breaks or between employee shift changes. This time is specifically chosen so that the only air consumption within the piping is that of the leaks and thus, the majority of the energy and power consumed during this time is noted to be used to feed the air leaks. The collected data is then used to extrapolate and calculate the energy and power consumed by these leaks for the rest of the year. There are, however, a few problems that arise when using such a method to understand the effects of the leaks in the system throughout the year. One of the issues is that it is assumed that the air and pressure lost through the found leaks are constant even during the production hours i.e. the hours that there is active air consumption by the pneumatic devices on the floor, which may not be the case due to the increased air flow rates and varying pressure within the line which can cause an increase in the amount of air lost through the same orifices that was initially detected. Another challenge that arises with using only the data collected during a single non-production time period is that there may be additional air leaks that may be created later on, and the energy and power lost due to the newer air leaks would remain unaccounted for. As the initial estimates will not include the additional losses, the effects of the air leaks may be underestimated by the plant managers. To combat said issues, a continuous method of air leak analyses will be required so as to monitor the air compressors’ efficiency in relation to the air leaks in real time. By studying a model that includes both the production, and non-production hours when accounting for the leaks, it was observed that there was a 50.33% increase in the energy losses, and a 82.90% increase in the demand losses that were estimated when the effects of the air leaks were observed continuously and in real time. A real time monitoring system can provide an in-depth understanding of the compressed air system and its efficiency. Managing leaks within a compressed air system can be challenging especially when the amount of energy wasted through these leaks are unaccounted for. The main goal of this research was to find a nonintrusive way to calculate the amount of air as well as energy lost due to these leaks using time series pressure measurements. Previous studies have shown a strong relationship between the pressure difference, and the use of air within pneumatic lines, this correlation along with other factors has been exploited in this research to find a novel and viable method of leak accounting to develop a Continuous Air Leak Monitoring (CALM) system.

手術後の呼吸器からの空気漏出（エアリーク）と腹部及び胸部癒着はそれぞれ、未だに臨床にて大きな課題である。本研究では、安全性に優れた植物性多糖類のアルギン酸ナトリウムに着目し、ゲルやスポンジの材形に加工した。これをPGA不織布と併用して新規エアリーク防止材を開発した。この新規材料は、エアリーク防止だけでなく癒着防止に対しても優れた効果を発揮した。将来的に、この新規材料は、従来材料よりも優れた医療材料として臨床応用されることが期待できると考えられる。 / Sodium alginate is polysaccharide extracted from seaweed and used as a biomaterial clinically. The alginate in this study was used as gel- or sponge-formed and combined with a polyglycolic acid (PGA) mesh, a useful biomaterial clinically; namely this combination was the new sealing material. The purpose of this study was to prevent pulmonary air leak without inducing adhesion. This study was composed of the four animal experiments; the first half of them was about preventing air leak and the latter was about preventing adhesion. All experiments showed that new sealing material was superior to the conventional treatments. Therefore the new sealing material was expected to be applied clinically to a sealing material, which also has an anti-adhesive effect. / 博士(理学) / Doctor of Philosophy in Science / 同志社大学 / Doshisha University

Syfte: Syftet är att genom en strukturell jämförelse av fallstudiens undersökningsobjekt få en överblick över kostnaden för arbetsutförandet av två luttätnings- och provtryckningsmetoder. Detta för att ta fram vilken metod som är lämpligast att tillämpa med avseende på kostnad.  Metod: Metoderna som tillämpats för att besvara målet var observationer, mätningar, beräkningar, litteraturstudie samt intervjuer. Den huvudsakliga metoden som användes var observationstekniken ”observatör som deltagare”. Intervjuer tillämpades för att anbringa ny kunskap men även verifiera empirin hämtad från observationerna.  Resultat: Studien visar att det finns både mindre och markanta skillnader mellan objektens lufttätnings- och provtryckningsmetoder som genererar både för och nackdelar. De största skillnaderna var framförallt vid fönster- och dörrutförandet, materialvalet i installationsväggen och om en tidig provtryckning utförs eller inte. Fördelarna med Gripen var att de inte var beroende av utomstående aktörers utförande vid fönsteranslutningen samt att de hade ett moment mindre under kontrollen av klimatskalet. Studien visar även att Gripen hade en lägre totalkostnad för lufttäthetsarbetet än Vimans Trädgård. Dock var kostnaden per kvadratmeter desto högre för varje färdigställd kvadratmeter. Efter en noggrann strukturell jämförelse bedömdes Vimans Trädgårds tillvägagångssätt var den mest kostnadseffektiva lufttätnings- och provtryckningsmetoden utifrån kr/kvm, se Tabell 13. Konsekvenser: Studien visar att båda objektens metoder fungerar för att nå byggnadens ställda lufttäthetkrav. Då metoderna liknade varandra på många punkter kunde slutsatsen dras att lufttätningsutförandet av fönster- och dörranslutningar hade en stor inverkan på tiden samt kostnaden. Slutligen kan följande rekommendationer ges, en byggnads lufttäthet bör säkerställas i ett tidigt skede, företagens luftätningsmetoder bör fortsätta utvecklas samt en enhetlig lufttätnings- och provtryckningsmetod bör utformas och appliceras inom hela företaget. Begränsningar: Rapportens undersökningsstrategi är en kvantitativ fallstudie. Studien begränsas till fallstudiens båda undersökningsobjekt och deras lufttätnings- samt provtryckningsmetod utan avseende till materialkostnader. Undersökningen begränsas även till objektens förutsättningar som materialval men tar ingen hänsyn till geografisk placering eller väderstrecksorientering. Detta medför att studien är giltig under specifika förhållanden. Vid en eventuell upprepning kan studien påvisa andra resultat och generera skilda slutsatser än det som vidtagits i denna utredning. / Purpose: The purpose is to provide an overview of the cost of the work performance of two air tightening and pressure testing methods through a structural comparison of the case study's investigative objects. This is to find out which method is most appropriate to apply in terms of cost. Method: The chosen methods, used to answer the goal, were observations, measurements, calculations, literature studies and interviews. The main method used was the observation technique "observer as a participant". Interviews were applied to conceive new knowledge, but also to verify the information from the observations. Findings: The study shows that there are both minor and significant differences between the objects air tightening and pressure testing methods that generate both pros and cons. The main differences were mainly the execution of the windows and doors, the choice of materials in the installation wall and if an early pressure test is performed or not. The benefits of Gripen were that they were not dependent on external operator’s performance at the window connection and that they had a moment less under the control of the climate scale. The study also shows that Gripen had a lower total cost of air tightness than Vimans Trädgård. However, the cost per square meter was the higher for each completed square meter. After a careful structural comparison, Vimans Trädgård ́s approach was evaluated as the most cost-effective air tightening and pressure testing method, see Table 13.  Implications: The study shows that the air tightening methods of both objects work to reach the building's airtightness requirements. As the methods were similar at many points, it could be concluded that the air tightening of window- and door connections had a major impact on time as well as the cost. Finally, the following recommendations that can be given is, building airtightness should be ensured at an early stage, companies' air tightening and pressure testing methods should continue to evolve and a uniform air tightening and pressure testing method should be designed and applied throughout the companies. Limitations: The report's investigation strategy is a quantitative case study. The study is limited to two study objects of the case study and their air tightening and pressure testing method without regard to material costs. The investigation is also limited to the object's conditions as material choice, but does not consider geographical location or weather-orientation. This means that the study is valid under specific conditions. In the event of a repeat, the study can demonstrate other results and generate different conclusions than those undertaken in this investigation.