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.

M.S.

The effects of fiber reactive and direct dyes on certain physical properties (tenacity, elongation, and initial modulus) of cotton fibers were investigated. Raw cotton fiber and raw yarn spun from the same batch of fiber were obtained. Fiber and yarn were processed by scouring, bleaching, and dyeing with both dyes, using an Ahiba Texomat Dyeing Apparatus, and the appropriate chemical systems. Fibers from treated fiber and fibers removed from treated yarns were tested after each treatment step, using an Instron Tensile Tester. The Wilks multivariate F test was used to determine whether or not significant differences existed between sequential treatments, and between fibers treated as fiber or as yarn. When significant differences were indicated, univariate analysis of variance was computed to identify the property(s) responsible. The results of this study indicated that the physical properties of both fiber reactive dyed and direct dyed fibers were not significantly different from each other or from the bleached fiber from which they were dyed. The properties of bleached (and dyed) fibers were significantly different (lower tenacity and elongation, higher initial modulus) from untreated or scoured fibers, indicating that the bleaching step was responsible for most of the changes noted. The properties of fibers treated as fiber were generally different (lower tenacity, higher elongation, lower initial modulus) than those of fibers removed from yarn. / M.S.

Tableau d’honneur de la Faculté des études supérieures et postdoctorales, 2015-2016 / Ce mémoire de maîtrise porte sur l’obtention d’une preuve de concept d’antenne textile capable de transmettre des données pertinentes, telles qu’un électrocardiogramme. Les antennes ont été fabriquées à l’aide de méthodes de métallisation chimique. En particulier, la déposition d’argent et de cuivre par réduction chimique ainsi que l’électrodéposition de cuivre ont été utilisés afin de métalliser des capillaires de différents matériaux. Ces capillaires ont été configurés en antennes filaires pour obtenir un dipôle demi-onde et une antenne boucle. Un travail parallèle a été fait pour développer l’antenne à fuite «Leaky CoaXial cable» (LCX) qui consiste en un câble coaxial dont la gaine métallique extérieure est ouverte en « fenêtres » afin de laisser fuir les champs électromagnétiques. Il existe de nombreuses applications potentielles aux antennes textiles, comme par exemple la localisation par Global Positioning System (GPS) de personnes kidnappées, la surveillance médicale à distance ou encore la transmission de données biométriques pour un entraînement physique de pointe. Pour démontrer la viabilité d’applications biométriques, nous avons décidé d’amplifier un signal cardiaque et de le transmettre via la bande de fréquence Industrielle, Scientifique et Médicale (ISM) à 2.45 GHZ aussi utilisée pour le Wi-Fi. / This master’s thesis treats the obtention of a proof of concept of a textile antenna able to transmit pertinent data such as electrocardiograms. Those antennas were fabricated using methods of chemical metalization. Particularly, the chemical reduction of silver and copper and the electrodeposition of copper was used to metallize capillaries made of different materials. These capillaries have been configured as filar antennas to obtain half-wave dipoles and loop antennas. A parallel work was done to develop the leaky feeder known as «Leaky Coax» (LCX) that consist in a coaxial cable of which the outer metallic layer is opened in windows to let the electromagnetic field leak out. There exist numerous potential applications to textile antennas, for example : clothesintegrated Global Positioning System (GPS) setups for the localization of kidnapped people, remote medical surveillance, or transmission of biometric data for cutting-edge sportive training. To demonstrate the viability of biometric applications, we decided to amplify a cardiac signal and to transmit it via the 2.4GHz Industrial, Scientific and Medical (ISM) frequency band that is also used for Wi-Fi networks.

En raison de la nature intime des interactions homme-textiles (essentiellement, nous sommes entourés par les textiles 24/7 - soit sous la forme de vêtements que nous portons ou comme rembourrage dans nos voitures, maisons, bureaux, etc.), les textiles intelligents sont devenus des plates-formes de plus en plus attrayantes pour les réseaux de capteurs innovants biomédicaux, transducteurs, et des microprocesseurs dédiés à la surveillance continue de la santé. En même temps, l'approche commune dans le domaine des textiles intelligents consiste en l'adaptation de la microélectronique planaire classique à une sorte de substrat souple. Cela se traduit souvent par de mauvaises propriétés mécaniques et donc des compromis au niveau du confort et de l'acceptation des usagers, qui à leur tour peuvent probablement expliquer pourquoi ces solutions émergent rarement du laboratoire et, à l'exception de certains cas très spécifiques, ne soit pas utilisés dans la vie de tous les jours. Par ailleurs, nous assistons présentement à un changement de paradigme au niveau de l'informatique autonome classique vers le concept de calculs distribués (ou informatique en nuage). Dans ce cas, la puissance de calcul du nœud individuel ou d'un dispositif de textile intelligent est moins importante que la capacité de transmettre des données à l'Internet. Dans ce travail, je propose une nouvelle approche basée sur l'intégration de polymère, verre et métal dans des structures de fibres miniaturisées afin de réaliser des dispositifs de textiles intelligents de prochaine génération avec des fonctionnalités de niveau supérieur (comme la communication sans fil, la reconnaissance tactile, les interconnexions électriques) tout en ayant une forme minimalement envahissante. Tout d'abord, j'étudie différents modèles d'antennes compatibles avec la géométrie des fibres et des techniques de fabrication. Ensuite, je démontre expérimentalement que ces antennes en fibres multi-matériaux peuvent être intégrées dans les textiles lors d’un processus standard de fabrication de textiles. Les tests effectués sur ces textiles ont montré que, pour les scénarios «sur-corps et hors-corps», les propriétés émissives en termes de perte de retour (S11), le patron (diagramme) de radiation, l'efficacité (gain), et le taux d'erreur binaire (TEB) sont directement comparables à des solutions classiques rigides. Ces antennes sont adéquates pour les communications à courte portée des applications de communications sans fil ayant un débit de données de Mo/s (méga-octets par seconde) (via protocoles Bluetooth et IEEE 802.15.4 à la fréquence de 2,4 GHz). Des simulations numériques de taux d'absorption spécifique démontrent également le plein respect des règles de sécurité imposées par Industrie Canada pour les réseaux sans fil à proximité du corps humain. Puisque les matériaux composites de fibres métal-verre-polymère sont fabriqués en utilisant des fibres de silice creuses de diamètre submillimétrique et la technique de dépôt d'argent à l'état liquide, les éléments conducteurs sont protégés de l'environnement et ceci préserve aussi les propriétés mécaniques et esthétiques des vêtements. Cet aspect est confirmé par des essais correspondant aux normes de l'industrie du textile, l'étirement standard et des essais de flexion. De plus, appliquer des revêtements superhydrophobes (WCA = 152º, SA = 6º) permet une communication sans fil sans interruption de ces textiles sous l'application directe de l'eau, même après plusieurs cycles de lavage. Enfin, le prototype de textile intelligent fabriqué interagit avec l'utilisateur à travers un détecteur tactile et transmet les données tactiles à travers le protocole Bluetooth à un smartphone. Cette démonstration valide l’approche des fibres multi-matériaux pour une variété d'applications. / As we are surrounded by textiles 24/7, either in the form of garments that we wear or as upholstery in our cars, homes, offices, etc., textiles are especially attractive platforms for arrays of innovative biomedical sensors, transducers, and microprocessors dedicated, among other applications, to continuous health monitoring. In the same time, the common approach in the field of smart textiles consists in adaptation of conventional planar microelectronics to some kind of flexible substrate, which often results in poor mechanical properties and thus compromises wearing comfort and complicates garment care, which results in low user acceptance. This explains why such solutions rarely emerge from the lab and, with the exception of some very specific cases, cannot be seen in the everyday life. Furthermore, we are currently witnessing a global shift from classical standalone computing to the concept of distributed computation (e.g. so-called thin clients and cloud storage). In this context, the computation power of the individual node or smart textile device in this case, becomes progressively less important than the ability to relay data to the Internet. In this work, I propose a novel approach based on the idea of integration of polymer, glass and metal into miniaturized fiber structures in order to achieve next-generation smart textile devices with higher-level functionalities, such as wireless communication, touch recognition, electrical interconnects, with minimally-invasive attributes. First, I investigate different possible fiber-shaped antenna designs and fabrication techniques. Next, I experimentally demonstrate that such multi-material fiber antennas can be integrated into textiles during standard textile manufacturing process. Tests conducted on these textiles have shown that, for on-body and off-body scenarios, the emissive properties in terms of return loss (S11), radiation pattern, efficiency (gain), and bit-error rate (BER) are directly comparable to classic ‘rigid’ solutions and adequately address short-range wireless communications applications at Mbps data-rates (via Bluetooth and IEEE 802.15.4 protocols at 2.4 GHz frequency). Numerical simulations of the specific absorption rate (SAR) also demonstrate full compliance with safety regulations imposed by Industry Canada for wireless body area network devices. Since metal-glass-polymer fiber composites were fabricated using sub-millimetre hollow-core silica fibers and liquid state silver deposition technique, the conductor elements are shielded against the environment and preserve the mechanical and cosmetic properties of the garments. This is confirmed by the textile industry standard stretching and bending tests. Additionally, applied superhydrophobic coatings (WCA=152º, SA=6º) allow uninterrupted wireless communication of the textiles under direct water application even after multiple washing cycles. Finally, I fabricated a user-interactive and wireless-communicating smart textile prototype, that interacts with the user through capacitive touch-sensing and relays the touch data through Bluetooth protocol to a smartphone. This demonstration validates that the proposed approach based on multi-material fibers is suitable for applications to sensor fabrics and bio-sensing textiles connected in real time to mobile communications infrastructures, suitable for a variety of health and life science applications.

Wearable computers and e-textiles are becoming increasingly widespread in today's society. Motion capture is one of the many potential applications for on-body electronic systems. Previous work has been performed at Virginia Tech's E-textiles Laboratory to design a framework for a self-contained loose fit motion capture system. This system gathers information from sensors distributed throughout the body on a "smart" garment. This thesis presents the hardware and software components of the framework, along with improvements made to it. This thesis also presents an analysis of both the on-body and off-body network communication to determine how many sensors can be supported on the garment at a given time. Finally, this thesis presents a method for determining the accuracy of the smart garment and shows how it compares against a commercially available motion capture system. / Master of Science

Because of their ubiquity and low cost fabrication techniques, electronic textiles (e-textiles) are an excellent platform for pervasive computing. Many e-textile applications are already available in the commercial, military, and academic domains, but most are very highly specialized and do not lend themselves easily to reuse or alteration. The purpose of this work is threefold: development of a methodology for building flexible and reusable applications that facilitates their use in the evolution of more complex systems, creation of a resource manager that realizes the methodology and enforces quality of service guarantees on tightly constrained textile resources, and construction of a simulation environment that allows for the rapid development and reconfiguration of systems to circumvent the need for the expensive physical prototyping process. This work discuss the effectiveness and appropriateness of the deployed event-driven hierarchical service model for application development. Additionally, this work explores the results of providing fault tolerance and quality of service guarantees in a textile environment that is particularly susceptible to faults. Further addressed by this work is the success of rapid prototyping and evaluation of applications in the simulation environment. / Master of Science

No / The impregnation of items of clothing with drugs of abuse that are then smuggled through airports and ports of entry is a growing problem for law enforcement. This work describes the application of portable Raman spectroscopic techniques for the analysis of a range of natural and artificial fibre items of clothing impregnated with drugs of abuse. Textile pieces were soaked with the solutions of the drugs then left overnight to dry prior to spectroscopic examination. The feasibility of detection of the characteristic Raman spectral bands in the presence of background matrix signals is demonstrated, even for dyed clothing. Definitive evidence for contamination of the items of clothing concerned can be acquired within 20-25 s, without any form of sample pre-treatment or extraction being necessary. The feasibility of automatic spectral recognition of such illicit materials by Raman spectroscopy has been investigated by searching a database stored on the spectrometer computer and the use of principal component analysis. Copyright (c) 2014 John Wiley & Sons, Ltd.

Yes / This chapter describes a collaborative project funded by Grants for All, Arts Council England, led by artist Karina Thompson, together with researchers from the Biological Anthropology Research Centre (BARC), School of Archaeological and Forensic Sciences, University of Bradford. The artworks took digitised historic clinical radiographs and digitised human skeletal pathological data from the landmark Digitised Diseases, and From Cemetery to Clinic digital bioarchaeology resources developed by colleagues from Visualising Heritage as a starting point. In addition to a series of small-scale installations displayed alongside the Biological Anthropology Research Centre teaching collection, large-scale exhibition pieces were displayed as part of national and international exhibitions. Collectively these works draw attention to the potential of digital bioarchaeology, whilst ensuring the importance of humanising the documentation of disease through time.