Background matching, a form of camouflage, involves species developing patterns and coloration that closely resemble their environment. Humans have utilized camouflage and background matching, particularly in military applications, to reduce detectable characteristics, known as signatures. Recent advancements in sensor systems necessitate the development of effective camouflage in the short-wave infrared (SWIR) range (0.9 – 2.5 µm). However, absorption of SWIR radiation is heavily influenced by water, and dry textile materials may be easily detectable against a forest background due to their low water content. To address this challenge, this master's thesis explores the integration of hydration onto a textile fabric to reduce the signature in SWIR. Various fabric types were included in this study. The optical properties of these textiles, both when wet and dry, were evaluated using SWIR imaging and UV-VIS-NIR spectroscopy, and compared to foliage. Surface modifications were employed to introduce hydrophobic properties to the fabric, such as the application of water-repelling agents (Nikwax and OrganoTex) or functionalized silica nanoparticles. The water evaporation rates of untreated and surface-treated fabrics were assessed. However, the hydrophobic surface did not significantly reduce water evaporation from the fabrics. Similarly, the addition of a nanocellulose-based hydrogel on the fabric surface did not result in a significant change in evaporation. Combining the hydrogel with water-repelling solutions in a multilayer configuration indicated prolonged evaporation, but further tests are required to validate this finding. This master's thesis demonstrates that introducing water into a dry textile fabric alters its spectral properties, making it more similar to foliage. However, the primary challenge lies in retaining water within the material for improved camouflage in SWIR wavelengths.

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Modern firefighter protective equipment is excellent at protecting firefighters from surrounding heat, but how effective is at deflecting incoming radiant heat, and would the use of more reflective textiles, be able to further increase the equipment’s protective properties? This study aims to understand the different properties that reflective materials, compared to standard firefighter outer layers, have against radiative heat flux. The textiles of firefighter turnout gear and the reflective textiles used in the smelting industry have been examined when exposed to varying levels of radiant heat in a cone calorimeter. The materials were examined before and after a layer of soot was applied to them, to understand their capabilities if used in a soot-rich environment. The change in material emissivity, when soot was applied, could then be calculated for each material. The heat reducing properties of the sooted and non sooted materials emissivities were tested, using computer simulations of a firefighter’s full turnout gear. First the radiative and convective heat fluxes were compared within a computational fluid dynamics software called FDS, second the skin level temperature was calculated using VGP, a finite element software that accounts for heat flow further into the skin and body.  During the experiment it was found that the emissivity of the reflective material even after soot application, performed better than that of the standard firefighter gear. In the simulations, the sooted reflective material emissivity would reduce the total heat flux to the firefighter with an average of 19% compared to the sooted standard turnout gear. Using the temperature of 44 °C as the limit for human skin damage, the use of a reflective emissivity would allow a 19% longer exposure to the same incident heat before possible skin damage would occur. Reducing the emissivity of current turnout gear would prove valuable as a method of reducing heat accumulation in a firefighter, especially at key areas more susceptible to the radiative heat flux from smoke-layers and radiative flames. This would in turn provide safer work environments for structural firefighting by reducing heat stress during active operations.

This paper is about MusiCushions: Interactive cushions to control external speakers in a living room. The interactive cushions are made of smart and interactive textiles, which acceptance has been profoundly investigated. Several studies have come to the conclusion that the most important feature for acceptance of smart and interactive textiles is the aesthetics of the textile interface. Therefore, this study investigates the question: How is integration of interactive cushions in the home environment affected by design concepts with different levels of explicit interaction and types of use cues? The method used in this study is based on constructive design research (CDR), where the design process consisted of moodboarding, sketching, prototyping and evaluation. Three prototypes were built and tested in two different user observations. The interactive cushions were considered well integrated in the home environment but there is room for improvement of usability. The evaluation showed that visual cues were the most important feature for usability but that there is a trade off between use cues and aesthetics. / Denna studie handlar om MusiCushions: Interaktiva kuddar att kontrollera externa högtalare med i ett vardagsrum. De interaktiva kuddarna är gjorda av smarta och interaktiva textilier, vars acceptans har varit grundligt utforskad i tidigare studier. Flera studier visar att den viktigaste faktorn för acceptans av smarta och interaktia textilier är estetiken av ett textilt gränssnitt. Därför undersöker denna studie frågan: Hur är integrering av interaktiva kuddar i hemmet påverkad av design koncept med olika nivåer av explicit interaktion och typer av use cues? Metoden som denna studie är baserad på är "Constructive design research" (CDR) och design processen bestod av utformande av moodboards, sketcher, prototyper och utvärdering. Tre prototyper var utvecklade och testade i två olika användarobservationer. De interaktiva kuddarna ansågs vara väl integrereade i hemmet, men det finns utrymme för användbarheten att förbättras. Utvärderingen visade också att visuella use cues var den viktigaste faktorn för användbarhet, men att det måste göras en avvägning mellan use cues och estetik då den ena påverkar den andra.

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Yes / Nowadays Fiber Reinforced Polymers (FRPs) represent a well-established technique for rehabilitation of Reinforced Concrete (RC) and masonry structures. However, the severe degradation of mechanical properties of FRP under high temperature and fire as well as poor sustainability represents major weak points of organic-based systems. The use of eco-friendly inorganic geopolymeric matrices, alternative to the polymeric resins, would be highly desirable to overcome these issues. The present work aims to investigate the bond characteristic of a novel Steel Reinforced Geopolymeric Matrix (SRGM) strengthening system externally bonded to a concrete substrate having low mechanical properties. SRGM composite material consists of stainless steel cords embedded into a fireproof geopolymeric matrix. Single-lap shear tests by varying the bonded length were carried out. The main failure mode observed of SRGM-concrete joints was debonding at the fiber-matrix interface. Test results also suggest the effective bond length. On the basis of the experimental results, a cohesive bond-slip law was proposed. / Part of the analyses were developed within the activities of Rete dei Laboratori Universitari di Ingegneria Sismica (ReLUIS) for the research program funded by the Dipartimento di Protezione Civile (DPC), Progetto DPC/ReLUIS 2016–AQ DPC/ReLUIS 2014–2016.

The huge advancement in the textiles industry and the accurate control on the mechanization process coupled with cost-effective manufacturing offer an innovative environment for new electronic systems, namely electronic textiles. The abundance of fabrics in our regular life offers immense possibilities for electronic integration both in wearable and large-scale applications. Augmenting this technology with a set of precepts and a simulation environment creates a new software/hardware architecture with widely useful implementations in wearable and large-area computational systems. The software environment acts as a functional modeling and testing platform, providing estimates of design metrics such as power consumption. The construction of an electronic textile (e-textile) hardware prototype, a large-scale acoustic beamformer, provides a basis for the simulator and offers experience in building these systems. The contributions of this research focus on defining the electronic textile architecture, creating a simulation environment, defining a networking scheme, and implementing hardware prototypes. / Ph. D.