Tesis: "PAPER SENSORS"

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Novell, Recasens Marta. "Paper-based potentiometric platforms for decentralised chemical analysis". Doctoral thesis, Universitat Rovira i Virgili, 2015. http://hdl.handle.net/10803/313994.

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En les darreres dècades, el món ha experimentat profunds canvis socials i tecnològics. Entre aquests, són destacables les tendències emergents d’anàlisis descentralitzats i de xarxes de sensors, que estan tenint un gran impacte en moltes àrees, especialment en el sistema sanitari. El desenvolupament d’eines per a realitzar anàlisis fora del laboratori de forma robusta, simple i econòmica, serà de gran ajuda per generar, per exemple, eines de diagnòstic assequibles. Per complementar aquestes tendències, aquesta tesis presenta el desenvolupament d’una eina analítica nova per anàlisis descentralitzats, usant paper modificat amb nanotubs de carboni com a substrat i la potenciometria com a tècnica de detecció. Els nanotubs de carboni s’han incorporat amb èxit sobre un paper de filtre convencional, convertint-lo així en conductor, i proporciona’t-li habilitat transductora ió-electró. Amb aquesta plataforma s’han desenvolupat elèctrodes selectius de ions per a diferents ions –mantenint el mateix rendiment analític que els elèctrodes convencionals- així com també un elèctrode de referència. La demostració de que aquesta plataforma pot solucionar un problema analític s’ha dut a terme a través del desenvolupament d’una cel·la potenciomètrica complerta de paper per a la detecció de liti en sang. Aquests elèctrodes també han estat combinats amb èxit amb un potenciòmetre d’identificació per radiofreqüència (RFID), cosa que permet el seu ús de forma descentralitzada. Altres aplicacions possibles, juntament amb les limitacions del sistema es discuteixen en detall. En definitiva, aquest treball obre la possibilitat de substituir sensors convencionals per aquesta plataforma més econòmica, obrint així tota una nova gama d’oportunitats.
En las últimas décadas, el mundo ha experimentado profundos cambios sociales y tecnológicos. Entre los cuáles son destacables las tendencias emergentes de análisis descentralizados y de redes de sensores, que tienen un gran impacto en muchas áreas, especialmente en el sistema sanitario. El desarrollo de herramientas para realizar análisis fuera del laboratorio de forma robusta, simple i económica, será de gran ayuda per generar, para generar, herramientas de diagnóstico asequibles. Para complementar estas tendencias, esta tesis presenta el desarrollo de una herramienta analítica nueva para análisis descentralizados, usando papel modificado con nanotubos de carbono como sustrato y la potenciometría como técnica de detección. Los nanotubos de carbono se han incorporado con éxito sobre un papel de filtro convencional, convirtiéndolo así en conductor, y proporcionándole habilidad transductora ion-electrón. Con esta plataforma se han desarrollado electrodos selectivos de iones para distintos iones manteniendo el mismo rendimiento analítico que los electrodos convencionales- así como también un electrodo de referencia. La demostración de que esta plataforma puede solucionar un problema analítico se ha hecho a través del desarrollo de una celda potenciométrica completa de papel para la detección de liti en sangre. Estos electrodos también se han combinado con éxito con un potenciómetro de identificación por radiofrecuencia (RFID), cosa que permite su uso de forma descentralizada. Otras aplicaciones posibles, junto con las limitaciones sistema se discuten en detalle. En definitiva, este trabajo abre la posibilidad de substituir los sensores convencionales por esta plataforma más económica, abriendo así tota una nueva gama de oportunidades.
During the last decades, the world has undergone deep social and technological changes. Remarkably are the emerging trends of decentralised analysis and sensing networks, which are having a deep impact in many areas, especially in the healthcare system. The development of tools for performing measurements out of the lab in a robust, simple and cost-effective way will be of great help to generate, for example, affordable diagnostic tools. To complement this trends, this thesis presents the development of a novel analytical tool for decentralised measurements, by using paper as a substrate modified with carbon nanotubes (CNT), and potentiometry as detection approach. CNTs have been successfully incorporated over a conventional filter paper making it conductive, and giving to it ion-to-electron transduction capability. Over this platform ion-selective electrodes for different ions have been developed –keeping the same analytical performance as conventional electrodes- as well as a reference electrode. The demonstration that this platform can solve an analytical problem has been proved through the development of a complete paper cell for the detection of lithium in blood. This electrodes have been also combined with a radio frequency identification (RFID) potentiometer, which will allows its use in a decentralised way. Other possible application of this platform together with its limitations are also discussed. All in all, this work opens the possibility to substitute conventional sensors for this low-cost paper sensors, thus unlocking a whole new range of possibilities.

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2

Jain, Ishan. "Paper-Based Sensors for Contaminant Detection Using Surface Enhanced Raman Spectroscopy". Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/53946.

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Surface enhanced Raman spectroscopy (SERS) is highly promising analytical technique for trace detection of analytes. It is particularly well suited for environmental analyses due to its high sensitivity, specificity, ease of operation and rapidity. The detection and characterization of environmental contaminants, using SERS is highly related to the uniformity, activity and reproducibility of the SERS substrate. In this thesis, SERS substrates were produced by gold nanoparticle formation on wax patterned chromatography paper. In situ reduction of hydrogen tetrachloroaurate (gold precursor) by trisodium citrate dihydrate (reducing agent) was used to produce gold nanoparticles within a paper matrix. These gold nanoparticle based SERS substrates were analyzed by FE-SEM, UV-Vis and Raman spectroscopy. This work discusses the SERS signal enhancements for Raman active MGITC dye for a series of substrates prepared by in situ reduction of gold salt and pre-produced gold nanoparticles. UV-Vis analysis was performed to understand the effect of different molar ratio (reducing agent to gold precursor) and reaction time on the size and shape of the localized surface plasmon resonance (LSPR) band that dictates the SERS enhancements. It was concluded that lower molar ratio (1:1 and 2:1) of citrate-to gold produced better SERS signal enhancements and broader LSPR band. Therefore, use of lower molar ratio (MR) was recommended for paper-based substrates using in situ-based reduction approach.
Master of Science

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3

Araujo, William Reis de. "Desenvolvimento de sensores eletroquímicos e colorimétricos para aplicações em amostras de interesse forense". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-18082016-084906/.

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Esta tese apresenta os estudos e esforços visando ao desenvolvimento de sensores químicos para aplicações diversas na área forense. Foram desenvolvidos métodos eletroanalíticos para detecção e quantificação de alguns compostos comumente encontrados na adulteração de amostras de drogas de abuso (procaína, fenacetina, aminopirina, paracetamol, levamisol), além da cocaína e estudos fundamentais sobre o comportamento eletroquímico desses compostos. Empregaram-se também métodos eletroquímicos para quantificação de compostos tóxicos e perigosos como explosivos (ácido pícrico) e melamina por exemplo. Os trabalhos utilizando sensores eletroquímicos contemplam modificações eletroquímicas das superfícies eletródicas, utilização de sensores com polímeros molecularmentes impressos (MIP) e eletrodos descartáveis em papel utilizando diferentes técnicas voltamétricas e amperométricas, eletrodo disco rotatório (EDR) e microbalança de cristal de quartzo. Além da fabricação de dispositivos analíticos descartáveis em papel empregando detecção eletroquímica utilizou-se também a detecção colorimétrica para quantificação de alguns dos principais adulterantes de amostras de apreensão de cocaína, como procaína e fenacetina, bem como análises e discriminações de compostos explosivos (peroxi e nitro compostos) nessas plataformas portáteis e de baixo custo. Os métodos foram sempre desenvolvidos visando característicos como: facilidade, praticidade, baixo custo e portabilidade para análises diretamente no local de medida com mínima infraestrutura laboratorial. Por fim, são apresentados alguns estudos realizados durante estágio de pesquisa no exterior (Universidade da Califórnia - San Diego (UCSD)) na área de Wearable Sensors, em que foram desenvolvidos métodos para análises de micronutrientes no suor (zinco) e um metabólito (ácido úrico) na saliva usando sensores aplicados diretamente no corpo humano.
This thesis shows studies and efforts to the development of chemical sensors for different applications in the forensic field. Electroanalytical methods were developed for detection and quantification of some compounds (procaine, phenacetin, aminopyrine, acetaminophen, levamisole) commonly found in the drug of abuse adulteration process and cocaine, as well as, fundamental studies about the electrochemical behavior of these compounds. It was also employed electrochemical methods for quantification of hazardous compounds such as explosives (picric acid) and melamine. Analytical methods with electrochemical sensors included electrochemical modification of electrodic surfaces, molecularly imprinted polymers (MIP), and paper disposable electrochemical devices using different voltammetric and amperometric techniques, rotating disc electrode (RDE) and quartz crystal microbalance. In addition to the fabrication of paper disposable analytical devices with electrochemical detection, it was also used the colorimetric detection to quantify some of the major adulterants in cocaine seizure samples, such as procaine and phenacetin, as well as analysis and discrimination of explosive compounds (peroxy and nitro explosives) in these low cost portable platforms. All proposed methods were always developed aming at theses characteristics: ease, convenience, low cost and portability for analysis directly at the measurement site with minimal laboratory infrastructure. Finally, we presented some studies conducted during research internship abroad (University of California - San Diego (UCSD)) in the area of Wearable Sensors, which have been developed methods for micronutrient analysis in sweat (Zn) and a metabolite (Uric Acid) in saliva using sensors applied directly to the human body

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Schoberg, Paul, Harry Beatty y Robert A. McKinley. "ITC TENA-Enabled Range Roadmap Paper". International Foundation for Telemetering, 2012. http://hdl.handle.net/10150/581847.

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This paper discusses the Department of Defense (DoD) direction to provide an environment for realistic Test & Evaluation in a Joint operational context and enhance interoperability and reuse with other test ranges and facilities though the use of the Test and Training Enabling Architecture (TENA) and connectivity to the Joint Mission Environment Test Capability (JMETC) joint test infrastructure. The intent of the "TENA-Enabled Range Roadmap" is to describe how TENA would be incorporated into PMRF's range infrastructure through both near-term upgrades and long-term system replacement. While details of this implementation plan are specific to PMRF, this roadmap can serve as a blueprint for TENA implementation at other ranges throughout the DoD.

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Koehly, Rodolphe. "Fabrication of sustainable resistive-based paper touch sensors: Application to music technology". Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104691.

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Building novel Digital Music Instruments (DMIs) requires the use of a variety of sensors to transduce human actions to electronic signals that will control sound synthesis variables. Among them, contact (force/pressure) sensors such as the Force Sensing Resistors (FSR) are the most commonly used in the design of DMIs. Similar commercial sensor designs based on conductive materials also enable to detect position, displacement or flexion. Unfortunately, although commercial sensors can be easily found at electronic resellers, only a few standardised models with predefined sizes, shapes and electric characteristics can be purchased. Moreover, the quality of the sensor appears to depend on their shape and dimension. These limitations have direct implications on the design of novel DMIs, which actually need to be adapted to the existing offer of commercial sensors. After various investigations with polymers, textiles, adhesives and glues, we finally chose to focus on conductive paper as a generic material for producing sustainable, flexible and customisable contact sensors. This thesis study presents two directions on paper sensors investigations: We first began by studying the potential of building paper contact sensors using industrial paper. This type of paper is originally produced to provide optimal colour properties and is not optimised for use as a conductive material. Nevertheless, it has been shown that it provides a very efficient choice for the design of custom sensors. Several sensor prototypes were built using samples of four industrial papers from three main manufacturers (ArjoWiggins (Canson), Fabriano, and PASCO) and have been used in the design of various gesture controllers. In order to verify the electrical behaviour of these prototypes, we developed a special test machine that enabled us to characterise the sensor's properties in terms of repeatability, drift and hysteresis, and to compare the results with commercial sensors. The second step was to consider how to produce such a paper. Laboratory experiments were performed to evaluate the influence of the papermaking process as well as the chemicals to be added to optimise the retention and formation of a uniform mix of pigments and fibres, enabling the fabrication of a rough, porous, compressible but still elastic material. Papers with various amounts of pigment and different sheet structures were made and characterised in order to evaluate the influence of the paper characteristics onto their electrical resistance. Resulting materials were also characterised with the test machine and compared to other types of resistive materials. This research contributes to the promotion of alternative solutions for the development of contact sensors. In particular, it shows that conductive paper and inks are an ecological alternative to conducting polymers for producing custom contact sensors. Paper sensors can replace industrial sensors in many applications, as they are equally efficient. Moreover they are recyclable or reusable, flexible and customisable, therefore extending the capabilities of industrial solutions. The production of such a paper will provide researchers with raw materials to produce their own sensors and realise new DMIs, such as the ones presented in this thesis. Apart from their usefulness in acquiring expert musical gestures, paper sensors have potential applications in many other fields such as medical (e.g. as hospital bed sheet), security (e.g. sensitive floors), intelligent packaging, etc. Multi-disciplinary research is a profitable way for creating new technological outputs. Conductive paper can provide new ways of building DMIs at moderate cost and with an environmental-friendly label. Music and arts can in return offer an efficient and sensitive proof-of-work to convince industries that conductive papers have a major potential in other applications.
La fabrication de nouveaux instruments musicaux numérique (IMN) nécessite l'utilisation de plusieurs types de capteurs afin de convertir les actions humaines en signaux électroniques pour le contrôle de variables de synthèse sonore. Parmi eux les capteurs de contact (force/pression) tels que les "Force Sensing Resistors" (FSR) sont les capteurs les plus utilisés. Même si des capteurs commerciaux peuvent facilement êtres trouvés chez des détaillants en électronique, seul un nombre limité de modèles standardisés, avec des tailles, des formes et des caractéristiques électriques prédéfinies, peuvent êtres achetés. Ces limitations ont des conséquences directes sur le design de nouveaux IMN qui doivent ainsi se limiter aux offres commerciales existantes.Après divers essais utilisant des polymères souples, des textiles, et des colles, nous avons choisi de nous concentrer sur les papiers conducteurs comme matières premières pour produire des capteurs de contact sensibles et adaptables. Ces recherches de thèse se sont alors orientées vers deux directions.Premièrement, nous avons commencé par fabriquer des capteurs à partir de papiers industriels à l'origine produit pour fournir des papiers colorés, et non pour une utilisation en tant que matériau conducteur. Nous avons montré néanmoins que ce papier conducteur est un matériaux sensible et exploitable. Plusieurs prototypes de capteurs ont ainsi été fabriqués en utilisant des échantillons de quatre types de papiers industriels provenant de trois manufacturiers (ArjoWiggins (Canson), Fabriano et PASCO). Ces prototypes ont ensuite été utilisés pour le développement de divers contrôleurs gestuels. Afin de vérifier le comportement des capteurs en action, nous avons développé un banc d'essai permettant de caractériser les propriétés électriques de ces capteurs en termes de répétabilité, dérive et hystérésis, et de les comparer à ceux des capteurs commerciaux.La seconde direction consistait à rechercher comment produire de tels papiers. Des expériences de laboratoires ont permis d'évaluer réglages des processus de fabrication à privilégier et les additifs chimiques à ajouter pour optimiser la rétention et la formation d'un mélange uniforme de pigments et de fibres et la formation d'un papier rugueux, poreux et compressible mais toujours élastique. Plusieurs types de papiers ont été réalisés en faisant varier la quantité de pigments et la structure des feuilles afin d'évaluer l'influence des caractéristiques d'un papier sur sa résistance électrique. Cette recherche contribue à la promotion de solutions alternatives pour le développement de capteurs de contact. Elle montre en particulier que les papiers conducteurs et les encres conductrices sont une alternative écologique aux polymères conducteurs pour la production de capteurs de contact. Les capteurs en papiers peuvent remplacer les capteurs industriels dans de nombreuses applications. De plus, ils sont recyclables et adaptables à tous types de design. La production d'un tel papier va procurer un stock de matières premières aux chercheurs afin qu'ils produisent leurs propres capteurs et conçoivent de nouveaux IMN tels que ceux qui sont présentés dans cette thèse. De plus, mis à part leurs capacités pour le contrôle de gestes musicaux experts, les capteurs en papier ont des applications potentielles dans d'autres domaines tels qu'en médecine (monitoring de lits d'hôpitaux), sécurité et domotiques (sols et murs sensibles), emballages intelligents, etc…La recherche multidisciplinaire est un moyen susceptible de générer de nouvelles technologies. Le papier conducteur offre de nouveaux moyens de produire des IMN pour un coût modéré en plus d'un label environnemental. La musique et les arts permettent en retour d'offrir une application ludique, attirante qui à fait ses preuves afin de convaincre les industries que les papiers conducteurs ont un gros potentiel dans d'autres applications.

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Wigent, Mark y Robert A. McKinley. "TENA Implementation at Pacific Missile Range Facility (PMRF) Paper". International Foundation for Telemetering, 2013. http://hdl.handle.net/10150/579669.

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ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV
PMRF provides a volume of space, which may include any combination of below-surface, surface, above-surface environments to safely test, gather data, and monitor in real time, the performance of systems being developed. This paper discusses how TENA implementation in range instrumentation; including radar, optics, video, GPS, and telemetry systems; will enhance data acquisition and distribution of systems under test. While details of this implementation plan are specific to PMRF, this approach can serve as a blueprint for TENA implementation at other ranges throughout the DoD.

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Silva, José Ricardo da. "Desenvolvimento de sensores químicos de baixo custo visando ao monitoramento da qualidade e da potabilidade de águas". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-08022019-094800/.

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A falta de acesso à água potável ainda é um problema de saúde pública no Brasil. O desenvolvimento de novos métodos analíticos de baixo custo para o reconhecimento de amostras contaminadas é uma necessidade, pois análises laboratoriais estão fora da realidade socioeconômica da população mais vulnerável. Visando contribuir para a resolução deste problema, esta tese apresenta esforços para o desenvolvimento de métodos de baixo custo para a análise de qualidade de águas ambientais. Foi estudada a associação de ferramentas quimiométricas com sensores voltamétricos para tentar discriminar amostras de águas contaminadas com espécies eletroativas. O modelo desenvolvido foi capaz de discriminar de forma satisfatória amostras contaminadas contendo chumbo(II), cobre(II), zinco(II) e nitrito. Os esforços para a redução do custo das análises também focaram no desenvolvimento de sensores com materiais de baixo custo. Um dos dispositivos voltamétricos propostos foi capaz de quantificar metais tóxicos e pesticidas, utilizando papel, grafite e cera. Foi desenvolvido também um sistema de agitação por som que resultou em um aumento significativo da sensibilidade dos dispositivos voltamétricos portáteis permitindo a quantificação de chumbo(II) até 48 nmol L-1, cádmio(II) até 370 nmol L-1 e zinco(II) até 340 nmol L-1. Outro sensor voltamétrico foi confeccionado utilizando apenas papelão como matéria prima, para o qual um laser de CO2 foi utilizado pela primeira vez com o intuito de pirolisar a superfície do papelão gerando estruturas de carbono condutoras. Sensores colorimétricos em papel foram testados com sucesso para a quantificação de fluoreto até 500 µmol L-1 em amostras de água mineral utilizando fotografias retiradas por um telefone celular para a construção de modelos12 de calibração. Com outro sistema colorimétrico em papel foi possível medir o pH de amostras utilizando um método de calibração multivariada. Como mostrado neste trabalho, o desenvolvimento e a integração dos dispositivos analíticos em papel é uma alternativa abrangente, confiável e de baixo custo para a análise da qualidade de águas ambientais.
The lack of access to safe water remains as a public health problem in Brazil. The development of new analytical methods for low cost contaminated samples recognition is necessary since the complete laboratorial procedures are away from the reality of the most socioeconomic vulnerable population. In order to contribute to solve this problem, this thesis shows our efforts to develop new low-cost analytical methods to evaluate environmental waters quality. The combination of chemometric tools with voltammetric sensors was studied to discriminate contaminated water samples with electroactive species. The proposed model was able to discriminate potable and contaminated samples containing lead(II), copper(II), zinc(II) and nitrite species. Efforts to reduce the analysis cost have also focused on the development of sensors using low-cost materials. A proposed voltammetric device fabricated with paper, graphite and wax was able to quantify heavy metals and pesticides. The use of a sound agitation system for the portable voltammetric devices resulted in a significant increase in the sensitivity allowing the quantification of lead(II) above 48 nmol L-1, cadmium(II) above 370 nmol L-1 e and zinc(II) above 340 nmol L-1 . Another voltammetric sensor was made for the first time using only cardboard as material and a CO2 laser to pyrolyze the cardboard surface generating conductive carbon structures. Paper colorimetric sensors were successfully tested for fluoride quantification in spring water samples based on photographs taken by a smartphone with a LOQ of 500 µmol L-1. Another paper colorimetric system was capable to measure the pH of samples using a multivariate calibration method. As shown in this thesis, the development and integration of analytical paper-based devices is a reliable and low-cost alternative for water quality analysis

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Hannani, Adnan. "Analysis of authentication systems : which is the most suitable for BTG?" Thesis, University West, Department of Technology, Mathematics and Computer Science, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-464.

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Gonçalves, Ricardo Miguel Romão. "Antenna design for passive sensors in non-conventional materials". Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17298.

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Doutoramento em Engenharia Eletrotécnica
Motivado pela larga expansão dos sistemas RFID e com o desenvolvimento do conceito de Internet das Coisas, a evolução no desenho e métodos de produção de antenas em suportes de materiais alternativos tem tido uma exploração intensiva nos últimos anos. Isto permitiu, não só o desenvolvimento de produtos no campo da interação homem-máquina, mas também tornar estes produtos mais pequenos e leves. A procura de novas técnicas e métodos para produzir eletrónica impressa e antenas em materiais alternativos e, portanto, uma porta aberta para o aparecimento de novas tecnologias. Isto aplica-se especialmente no mercado dos sensores, onde o peso, o tamanho, o consumo energético, e a adaptabilidade a diversos ambientes, têm grande relevância. Esta tese foca-se no desenvolvimento de antenas com suporte em materiais não convenvionais, como os já testados papel e têxteis, mas também na exploração de outros, desconhecidos do ponto de vista eléctrico, como a cortiça e polímeros biodegradáveis usados em impressão 3D. Estes materiais são portanto usados como substrato, ou material de suporte, para diversas antenas e, como tal, as propriedades electromagnéticas destes materiais têm de ser determinadas. Assim, e apresentado neste documento uma revisão de métodos de caracterização de materiais, bem como a proposta de um método baseado em linhas de trasmissão impressas, e a respectiva caracterização electromagnética de diversos materiais. Além disso, são propostos desenhos de antenas para diversos cenários e aplicações utilizando os materiais anteriormente mencionados. Com esta tese concluiu-se que a utilização de materiais alternativos e hoje uma realidade e os resultados obtidos são muito encorajodares para o desenvolvimento de um conjunto de sensores para aplicações RFID com uma grande capacidade de integração.
The advancement of the design and fabrication of antennas using textiles or paper as substrates has rapidly grown motivated by the boom of RFID systems and the developing concept of the Internet of Things. These advancements have allowed, not only the development of products for manmachine interaction, but also to make these products smaller and lighter. The search for new techniques and methods to produce printed electronics and antennas in alternative materials is therefore an open door for new technologies to emerge. Especially in the sensors market, where weight, size, power consumption and the adaptability to the target application, are of great importance. This thesis focuses on the development of antenna design approaches with alternative materials, such as the already tested paper and textiles, but also others relatively unknown, such as cork and biodegradable polymers used in 3D printing. These materials are applied to act as substrates, or support structures for the antennas. Therefore, their electromagnetic properties need to be determined. Due to that, a review of electromagnetic characterization methods, as well as the proposal of a custom method based on printed transmission lines, is presented in this document. Besides, several antenna designs, for di erent application scenarios, using the previously mentioned materials, are proposed. With this thesis it was proved that it is possible to develop passive sensors in di erent alternative materials for RFID applications and others, which shows great promise in the use of these materials to achieve higher integration in sensing and identi cation applications.

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Björk, Anders. "Chemometric and signal processing methods for real time monitoring and modeling using acoustic sensors : applications in the pulp and paper industry /". Stockholm, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4383.

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11

Zhu, Xuena. "Development of Point-of-Care Testing Sensors for Biomarker Detection". FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/2236.

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Point-of-care testing (POCT) is defined as medical testing at or near the site of patient care and has become a critical component of the diagnostic industry. POCT has many advantages over tests in centralized laboratories including small reagent volumes, small size, rapid turnaround time, cost-effectiveness, low power consumption and functional integration of multiple devices. Paper-based POCT sensors are a new alternative technology for fabricating simple, low-cost, portable and disposable analytical devices for clinical diagnosis. The focus of this dissertation was to develop simple, rapid and low cost paper-based POCT sensors with high sensitivity and portability for disease biomarker detection. Lateral flow strips (LFS) were used as the basic platform as it provides several key advantages such as simplicity, fast response time, on site and cost-effectiveness, and it can be used to detect specific substances including small molecules, large proteins and even whole pathogens, in a sample by immunological reactions. Earlier designs of paper strips lacked the quantitative information of the analyte concentration and could only provide single analyte detection at a time. In this study, a series of modifications were made to upgrade the platform to compensate for these limitations. First, we developed a gold nanoparticle based LFS for qualitative colorimetrical detection of bladder cancer related biomarkers in standard solutions and in urine samples. Second, by incorporating an image processing program “ImageJ”, a semi-quantitative LFS platform was established. The capability of the strip was evaluated by testing a small DNA oxidative damage biomarker in urine and cell culture models. Third, we combined the electrochemical method and colorimetrical method for quantitative biomarker detection. Finally, we integrated a commercialized blood glucose meter to quantitatively detection of two non-glucose biomarkers by converting their signals to that of glucose. The upgraded sensor could provide a noninvasive, rapid, visual, quantitative and convenient detection platform for various disease biomarkers. In addition, this platform does not require expensive equipments or trained personnel, deeming it suitable for use as a simple, economical and portable field kit for on-site biomarker monitoring in a variety of clinical settings.

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12

Alrammouz, Rouba. "Conception et réalisation d’un système de détection de gaz à faible coût sur substrat flexible". Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS134.

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Les préoccupations actuelles de protection de l’environnement et de la santé publique se focalisent sur la qualité de l’air dans l’industrie, les villes et foyers domestiques. De nos jours, les capteurs de gaz sur papier présentent un intérêt croissant au vu de leur faible coût, leur biodégradabilité, leur flexibilité, et leurs applications dans les textiles, les pansements et les emballages intelligents.L’oxyde de graphène (GO) est un dérivé du graphène qui présente des propriétés électriques, mécaniques et thermiques exceptionnelles. Ce matériau est très prometteur pour le développement de capteurs de gaz peu chers et fonctionnant à température ambiante.Dans ce contexte, cette thèse a pour objectif d’intégrer une couche sensible d’oxyde de graphène dans un papier poreux pour la détection de gaz. La première partie de ce travail est consacrée à la mise au point et à l’optimisation d’un processus de fabrication et de fonctionnalisation de capteurs capacitifs poreux sur papier. Un nouveau processus de réduction locale d’oxyde de graphène sur papier en électrodes est également introduit. Il s’agit de la thermocompression, économique et compatible avec la fabrication grande échelle.La seconde partie du travail porte sur l’étude des propriétés de détection d’humidité et d’ammoniac des capteurs. L’oxyde de graphène sur papier, présente une sensibilité élevée à l’ammoniac, l’humidité étant un gaz interférent. La réduction locale du GO en électrodes, et sa fonctionnalisation par de l’oxyde de zinc augmentent la sensibilité et la sélectivité des capteurs à l’humidité. Les capteurs fabriqués sont répétables, stables, reproductibles et flexibles
Current concerns for environmental protection and public health focus on air quality in industries, cities and households. Nowadays, paper-based gas sensors are of increasing interest due to their low cost, biodegradability, flexibility and applications in e-textiles, e-dressings and e-packaging.Graphene oxide is a derivative of graphene with exceptional electrical, mechanical and thermal properties. Graphène oxide is a promising material for the development of low-cost room temperature gas sensors.In this context, this thesis aims to integrate a graphene oxide sensing layer inside a porous paper substrate for humidity and ammonia detection. The first part of this work focuses on the fabrication, functionalization and optimization of capacitive porous gas sensors on paper. A new local reduction process of graphene oxide into electrodes is introduced. The process is hot-plating, a low cost technique compatible with large scale productionThe second part of this work studies the humidity and ammonia sensing capabilities of the sensors. Graphene oxide on paper exhibits a high sensitivity towards ammonia, with humidity as an interfering gas. The local reduction of graphène oxide into electrodes, and its functionalization with zinc oxide increased the sensitivity and selectivity of the device towards humidity. The fabricated sensors exhibit a good repeatability, reproducibility and flexibility

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Santhiago, Murilo 1984. "Construção e aplicação de dispositivos analíticos 2D e 3D à base de papel com detecção eletroquímica". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248388.

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Orientador: Lauro Tatsuo Kubota
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
Made available in DSpace on 2018-08-24T12:03:31Z (GMT). No. of bitstreams: 1 Santhiago_Murilo_D.pdf: 3375339 bytes, checksum: 5d945dd23cfef732a3e3d083685bedc0 (MD5) Previous issue date: 2014
Resumo: Neste trabalho descreve-se a construção e aplicação de dispositivos analíticos 2D e 3D à base de papel com detecção eletroquímica (ePAD). Os dispositivos foram construídos empregando o método de impressão com cera e diferentes tipos de papéis. Eletrodos de ouro foram utilizados juntamente com o conceito da separação cromatográfica em dispositivos microfluídicos. No canal microfluídico à base de papel foi possível realizar a separação de ácido ascórbico e dopamina em 14 minutos. A necessidade por processos de fabricação mais simples e de baixo custo nos motivou a estudar eletrodos de carbono em ePADs. Assim, eletrodos de grafite de lapiseira foram selecionados visando o desenvolvimento de um biossensor para glicose. O biossensor apresentou uma excelente resposta eletroquímica e um tempo de análise de 4 minutos. O mesmo eletrodo de grafite foi acoplado com um sistema de informação para determinação de p-nitrofenol. Assim, foi possível detectar 1,0 mmol L de p-nitrofenol em amostras de água e analisar/interpretar os resultados empregando um celular. Por fim, a necessidade por sistemas eletroquímicos com menores limites de detecção nos impulsionou a fabricar microeletrodos de pasta de carbono. Os microeletrodos foram fabricados em folhas de transparência e acoplados no papel empregando uma configuração do tipo sanduíche. Os dispositivos foram caracterizados eletroquimicamente na presença de cisteína e apresentaram uma constante cinética de 10 L mol s. Um limite de detecção de 4,8 mmol L para cisteína foi obtido empregando um arranjo de microeletrodos. Por fim, os microeletrodos de pasta de carbono foram utilizados para a construção de um biossensor visando a determinação de metil paration. O ePAD foi construído de modo a acomodar o substrato (acetiltiocolina) e a enzima (acetilcolinesterase) no mesmo dispositivo
Abstract: This thesis describes the construction and application of 2D and 3D electrochemical paper-based analytical devices (ePADs). The devices were constructed using the wax printing method and different types of papers. Gold electrodes were employed along with the concept of chromatographic separation in microfluidic devices. By using the paper-based microfluidic channel it was possible to perform the separation of ascorbic acid and dopamine in 14 minutes. The need for simpler and low cost manufacturing processes motivated us to study carbon electrodes in ePADs. Thus, pencil graphite electrodes were selected for the development of a biosensor for glucose. The biosensor exhibited excellent electrochemical response and analysis time of 4 minutes. The same graphite electrode was coupled to an information system for the determination of p-nitrophenol. Thus, it was possible to detect 1.0 mmol L of p-nitrophenol in water samples and analyze/interpret the results using a smartphone. Finally, the need for electrochemical systems with lower limits of detection made us to search for carbon paste microelectrodes. The microelectrodes were fabricated on transparency sheets and coupled on paper using a sandwich-type configuration. The devices were characterized electrochemically in the presence of cysteine and had a rate constant of 10 L mol s. A detection limit of 4.8 mmol L for cysteine was obtained using an array of microelectrodes. By last, carbon paste microelectrodes were used to construct a biosensor in order to determine methyl parathion. The ePAD was constructed to accommodate the substrate (acetylthiocholine ) and enzyme ( acetylcholinesterase ) in the same device
Doutorado
Quimica Analitica
Doutor em Ciências

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Duarte, Alcídia Micarla Afonseca. "Sensores passivos em suporte de papel". Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12814.

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Mestrado em Engenharia Eletrónica e Telecomunicações
O presente trabalho propõe-se superar o problema do funcionamento da tecnologia RFID num meio em presença de líquidos. Desta forma procedeu-se ao desenvolvimento de um rótulo que visa ser aplicado em garrafas de vinho ou champanhe. Incorporar RFID em rótulos permite maior velocidade e robustez na identificação do produto, sendo o principal interesse a sua versatilidade que permitirá associar diferentes funcionalidades. Para construir as antenas das tags foi necessário primeiramente estudar as caraterísticas do meio dielétrico, tendo sido necessário para isso, desenvolver um método de caraterização dielétrica. Estudou-se o papel e o vidro usando um método baseado em linhas de transmissão. Uma vez estudadas as caraterísticas dielétricas, foram dimensionadas e produzidas diferentes antenas, nomeadamente o rótulo com a presença de uma garrafa com água.
This work proposes a possible solution, in order to make RFID technology functional in the proximity of liquid. Thus we developed an intelligent label to be applied to wine or champagne bottles. Incorporate RFID in labels allows greater speed and robustness in product identification, being the versatility of it the main interest that will allow to associate different functionalities. To develop the tags antennas we had to first, study the dielectric characteristics, for which we developed a dielectric characterization method, based on transmission lines. Paper and glass were studied using this method. After the extraction of the different types of antennas were scaled and produced, namely the label for a water filled glass bottle.

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Ammineni, Chandini Muniratnam. "Design of Lignin Sensor for Identification of Paper Grades for an Automatic Waste Paper SortingSystem". NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20010907-181312.

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AMMINENI, CHANDINI MUNIRATNAM. Design of Lignin Sensor forIdentification of Paper Grades for an Automatic Waste Paper SortingSystem. (Under the direction of Dr. M. K. Ramasubramanian.)The purpose of this research has been to design a lignin sensor fornon-destructive, real-time identification of waste paper grades, toaid in automating a waste paper sorting process. The sensor iscapable of identifying about 500 papers in one second. It is based onthe principle that fluorescence light emitted from paper followingabsorption of visible light has a wavelength distribution determinedby the chemical composition of the paper. The sensor is the most critical part in waste paper sorting, whichhas hitherto not been automated due to the inability to design asensor that distinguishes paper grades. This sensor is vastlysuperior to all other sensors previously designed for this purposebecause, it does not use the conventional reflective type opticalproperties of paper, and this is the only sensor that can identifyall grades unlike the previous sensors that could identify only whiteledger papers.

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Hasan, Meqdad y Rahul Kali. "Method for Autonomous picking of paper reels". Thesis, Högskolan i Halmstad, Intelligenta system (IS-lab), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-16212.

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Autonomous forklift handling systems is one of the most interesting research in the last decades. While research fields such as path planning and map building are taking the most significant work for other type of autonomous vehicles, detecting objects that need to move and picking it up becomes one of the most important research fields in autonomous forklifts field. We in this research had provided an algorithm for detecting paper reels accurate position in paper reels warehouses giving a map of the warehouse itself. Another algorithm is provided for giving the priority of papers that want to be picked up. Finally two algorithms for choosing the most appropriate direction for picking the target reel and for choosing the safest path to reach the target reel without damage it are provided. While working on the last two algorithms shows very nice results, building map for unknown stake of papers by accumulating maps over time still tricky. In the following pages we will go in detail by the steps that we followed to provide these algorithms started from giving an over view to the problem background and moving through the method that we used or we developed and ending by result and the conclusion that we got from this work.

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Srinivas, Achanta. "A Measurement Tool for Consumption Pattern of Hand wiping Tissue Paper". Thesis, Blekinge Tekniska Högskola, Avdelningen för maskinteknik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2902.

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Due to environmental concerns and competition within the industry there is an imminent need by paper manufacturers to asses the paper consumption depending on the quality of the tissue paper. For this purpose, the consumption of tissue paper from a tissue vending machine needs to be monitored and calculated. A Hall Effect Sensor coupled with a Passive Infrared Sensor was used to monitor the flow of paper per Person. MATLAB is used as the programming language to read the signals from the sensors. The consumption obtained would be used to obtain better, less bulky design models. As well deduce an optimum paper dimensions to get reduce the paper consumption. Also, the FEM was done in ABAQUS for better blade design of Hand wiping system.
achantasrinivas@gmail.com +46 704406894

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Akin, Meriem [Verfasser]. "Paper-based anisotropic magneto-resistive thin film sensor for educational applications / Meriem Akin". Düren : Shaker, 2019. http://d-nb.info/119091767X/34.

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Jacquemoud-Collet, Fanny. "Etiquette RFID bas coût sur support papier : Optimisation du procédé industriel innovant / intégration d’une fonctionnalité capteur". Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20194.

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La RFID, pour Identification par Radio Fréquence, s'est considérablement développée depuis quelques années devenant un mode d'identification et de traçabilité incontournable. Les acteurs du marché sont nombreux et parmi eux, Tageos, société Montpelliéraine, a mis en place dès 2008 un procédé innovant de fabrication de l'étiquette RFID sur papier, économique et écologique. Cependant, même si les performances obtenues lors d'un précédent travail (Thèse C. Ramade 2008-2011) ont été suffisantes pour permettre la production de masse, elles ne sont pas optimales notamment vis-à-vis des résultats établis en laboratoire. C'est dans ce cadre-là que se positionne ce travail de thèse qui s'est réalisé toujours en étroite collaboration entre l'Institut d'Electronique du Sud et la société TAGEOS S.A.S. Nos efforts se sont focalisés : sur l'optimisation du processus de réalisation d'antenne RFID en travaillant sur l'analyse, les méthodes ou protocoles et les moyens techniques sur la préparation du substrat papier, sur des solutions alternatives et complémentaires de réalisation d'antenne RFID et de collage de la puce RFID et sur la fiabilisation et la qualité des produits finis. Par ailleurs, dans ce travail nous avons également démontré la valorisation de notre tag RFID bas coût par l'intégration d'un capteur et de sa fonctionnalité. Le processus de réalisation industriel d'un tel tag est abordé en tenant compte de celui de TAGEOS
The RFID, for Radio Frequency Identification, has grown considerably in recent years become an essential mode of traceability and identification. Market players are numerous and among them, Tageos (Montpellier, France) established since 2008 an innovative process for manufacturing the RFID tag on paper, economic and ecologic. However, even if the performances obtained during a previous work (Thesis C. Ramade 2008-2011) were sufficient to allow mass production, they are not optimal in particular with respect to the established results in laboratory. It is in this context that ranks this work which is always carried out in close collaboration between the Institute of Electronics of South and TAGEOS company S.A.S. Our efforts were focused : on process optimization of realization of RFID antenna working on the analysis, methods or protocols and technical resources on the preparation of the paper substrate, on alternative and complementary solutions to realize RFID antenna and RFID chip bonding and on the reliability and quality of finished products. Moreover, in this work we have also demonstrated the valorization of our low cost RFID tag by integrating a sensor functionality. The industrial process of producing of this tag taking accounts of TAGEOS process

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Rondão, Ana Inês Batista Lourenço. "Papel do eletrólito e elétrodos na performance de sensores de oxigénio". Doctoral thesis, Universidade de Aveiro, 2018. http://hdl.handle.net/10773/22961.

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Doutoramento em Ciência e Engenharia de Materiais
Os sensores de oxigénio são instrumentos de uso comum em diversos setores da indústria, em particular para controlo da atividade de oxigénio no aço fundido. O rigor da medição está intrinsecamente ligado às propriedades dos seus componentes, nomeadamente eletrólito e elétrodos. É neste âmbito que surge este trabalho, em parceria com a Rauschert Portuguesa, visando criar uma base de conhecimento sólida sobre este tipo de sensores. O eletrólito típico usado nestes sensores é a zircónia parcialmente estabilizada com magnésia (Mg-PSZ), devido a uma excelente combinação de propriedades, em grande parte relacionadas com o teor de fases cristalinas (monoclínica (C), tetragonal (T) e cúbica (C)). Na Mg-PSZ a percentagem de cada fase e a sua distribuição em termos microestruturais dependem da composição química e da temperatura máxima de sinterização, mas também das condições de arrefecimento. O estudo das relações entre composição, processamento e propriedades da Mg-PSZ foi o objetivo central deste trabalho. Prepararam-se materiais com composições entre os 2,5 e os 10% (percentagem molar) de MgO, sinterizados a 1700 °C, mas envolvendo diferentes perfis de arrefecimento. Estes materiais, juntamente com outros disponíveis no mercado ou fornecidos pela empresa (com reserva de informação sobre composição e processamento), foram primeiramente caracterizados por difração de raios-X (DRX), microscopia eletrónica de varrimento (MEV) e análise térmica dilatométrica (DIL). A caracterização elétrica incluiu espectroscopia de impedância (EI), condutividade total (usando uma técnica de 4 elétrodos), e determinação do limite inferior do domínio iónico (usando uma célula de concentração). Nos dois últimos casos usaram-se células de medição inteiramente desenvolvidas neste trabalho. Os resultados confirmaram um efeito composicional acentuado, mas igualmente uma forte relevância do perfil de arrefecimento no teor de fases, comportamento térmico e microestrutura. A caracterização elétrica evidenciou a complexidade dos efeitos composicionais e microestruturais, e originou alguma reflexão original face aos modelos usuais de tratamento desta informação. A quantificação de fases assumiu e assume grande importância na avaliação destes materiais, tendo sido desenvolvida uma metodologia original de tratamento de resultados de DIL que permite ultrapassar as limitações de análises superficiais envolvendo técnicas convencionais. Abre-se também assim uma porta para um estudo cinético mais detalhado sobre as transições de fases neste sistema. A determinação do limite inferior do domínio iónico, utilizando elétrodos com base no Al, revelou-se bastante eficaz face às técnicas geralmente utilizadas, permitindo demonstrar que os materiais ensaiados se posicionam de forma muito confortável face a materiais alternativos. Alguns testes com sensores, usando pares metal/óxido metálico como referência, confirmaram mais uma vez o bom posicionamento competitivo dos materiais ensaiados em termos de sinal e resistência ao choque térmico.
Oxygen sensors are instruments commonly used in various industrial sectors, in particular to control the oxygen activity in molten steel. The accuracy of the measurement is intrinsically linked to the properties of the sensor components, namely electrolyte and electrodes. This work, in partnership with Rauschert Portuguesa, is conceived to create a sound knowledge on this type of sensors. The typical electrolyte used in these sensors is partially stabilized zirconia with magnesia (Mg-PSZ), due to an excellent combination of properties, largely related to the content of crystalline phases (monoclinic (M), tetragonal (T) and cubic (C)). In Mg-PSZ the percentage and distribution of each phase in microstructural terms depend on the chemical composition and maximum sintering temperature, but also on cooling conditions. The study of the relationships between composition, processing and properties of Mg-PSZ was the central objective of this work. Several materials were prepared with compositions ranging from 2.5 to 10% (molar percentage) of MgO, sintered at 1700 °C, but involving different cooling profiles. These materials, along with others available in the market or supplied by the company (involving private information on composition and processing), were primarily characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and dilatometric thermal analysis (DIL).The electrical characterization included impedance spectroscopy (EI), total conductivity (using a 4 probe technique), and determination of the lower limit of the ionic domain (using a concentration cell). In the latter two cases, specific measurement cells were fully developed in this work. The results confirmed a strong compositional effect, but also a clear relevance of the cooling profile on phase content, thermal behavior and microstructure. The electrical characterization evidenced the complexity of the compositional and microstructural effects, and originated some original reflection with respect to the usual treatment of this information. Phase quantification was and is of great importance in the assessment of these materials. An original methodology of treatment of DIL data was developed circumventing the limitations of surface (only) analyses involving conventional techniques. This solution can be further used in detailed kinetic studies on phase transformations in this system. The determination of the lower limit of the ionic domain, using Al-based electrodes, proved to be quite effective against the techniques generally used, allowing to demonstrate that the tested materials are well positioned against alternative materials. Some sensor tests using metal/metal oxide reference couples confirmed again the good competitive positioning of the materials hereby tested in terms of signal and resistance to thermal shock.

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Rida, Amin H. "Conductive inkjet printed antennas on flexible low-cost paper-based substrates for RFID and WSN applications". Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28083.

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Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Dr. Manos Tentzeris; Committee Member: Dr. Gregory Durgin; Committee Member: Dr. Joy Laskar.

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Ataide, Vanessa Neiva de. "Desenvolvimento de sensores eletroquímicos de carbono visando à detecção de furosemida em amostras farmacêuticas e clínicas". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-20072018-083427/.

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Nos últimos anos, materiais baseados em grafeno têm atraído grande interesse na área eletroquímica devido às suas excelentes propriedades eletrônicas. Neste trabalho, apresentamos a obtenção de óxido de grafeno reduzido utilizando métodos eletroquímicos. A redução eletroquímica do óxido de grafeno (OG) foi realizada na superfície de um eletrodo de carbono vítreo (ECV) utilizando voltametria cíclica. O óxido de grafeno reduzido eletroquimicamente (OG-RE) foi caracterizado utilizando espectroscopia Raman, microscopia eletrônica de varredura (MEV), microscopia de força atômica (MFA), espectroscopia de fotoelétrons excitados por raios-X (XPS) e espectroscopia de impedância eletroquímica. A relação ID/IG obtida através dos espectros Raman do OG e do OG-RE foram de 0,98 e 1,15, respectivamente, indicando que o processo de redução resultou em uma maior desorganização estrutural. A espectroscopia de fotoelétrons de raios-X mostrou que a proporção entre C e O no OG foi de 45,7% e, que após a redução eletroquímica essa relação diminuiu para 38,5%. O eletrodo modificado com OG-RE foi empregado para quantificação de furosemida (FUR) em amostras farmacêuticas utilizando voltametria de pulso diferencial e análise por injeção em fluxo com detecção amperométrica. Os limites de detecção e quantificação calculados para o método proposto foram de 0,35 e 1,18 µmol L-1, respectivamente. Visando à aplicação em amostras de interesse clínico, fabricou-se um sensor descartável e de baixo custo para a detecção de FUR utilizando papel sulfite pintado com lápis de desenho e ativado por laser de CO2. Os estudos voltamétricos utilizando o [Ru(NH3)6]Cl3 mostraram que o transporte de massa neste dispositivo foi governado por difusão e que o tratamento com laser diminui a resistência a transferência de carga, assim como resultou em um menor problema relacionado ao envenenamento da superfície do eletrodo
In recent years, graphene-based materials have attracted great interest in the area of electrochemistry due to its excellent electronic properties. In this work, we present the production of reduced graphene oxide using electrochemical methods. The electrochemical reduction of graphene oxide (GO) was carried out on the surface of a glassy carbon electrode (GCE) using the cyclic voltammetry technique. Electrochemically reduced graphene oxide (ER-GO) was characterized using Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), Xray excited photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). ID / IG ratio obtained through Raman spectra of GO and ER-GO were 0.98 and 1.15, respectively, indicating that the reduction process resulted in greater structural disorganization. XPS showed that the ratio between C and O in the GO was 45.7% and that after electrochemical reduction this ratio decreased to 38.5%. The ER-GO modified electrode was used as a sensor for furosemide (FUR) in pharmaceutical samples using the techniques of differential pulse voltammetry and flow injection analysis with amperometric detection. The limits of detection and quantification for the proposed method were 0.35 and 1.18 µmol L-1, respectively. Aiming to the application in clinical samples a disposable, low-cost paper-based sensor for the detection of FUR was fabricated using office paper painted with drawing pencil and activated by CO2 laser. Voltammetric studies using [Ru(NH3)6]Cl3 have shown that mass transport in this device was controlled by diffusion and the laser decreases resistance to charge transfer, as well as, avoided the problem with electrode surface poisoning

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Paudyal, Janak 9255967. "Carbon Nanotube- and Gold Nanoparticle-Based Materials For Electrochemical and Colorimetric Sensing Applications". FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2996.

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Carbon nanotubes (CNTs) and gold nanoparticles (AuNPs) are widely used for sensing applications due to their distinctive electrical and optical properties, and we have explored the development of methods that enable the incorporation of these nanomaterials into new and improved sensing devices. As a means for fabricating simple, low-cost and fast detection platforms for various applications, we have developed paper-based electrochemical detection platforms based on CNTs or platinum nanoparticle (PtNP)-CNT composite materials. We describe the use of a paper-based, low density, a three-dimensional thin film of interconnected CNTs as an electrode material. We studied the electrochemical properties of these paper-based CNT electrodes and demonstrated their use as an electrochemical sensor for the sensitive detection of guanine-based nucleotides. We further describe the functionalization of this paper-based electrode by fabricating a PtNP-SWCNT hybrid film via a vacuum filtration-based method. The interconnected PtNP structure formed on top of the CNT-coated paper was directly used as an electrocatalyst for methanol oxidation. Compared to paper-based PtNP-SWCNT hybrid films formed by electrochemical deposition, hybrid films formed by vacuum filtration showed a higher electrochemical surface area and enhanced electrocatalytic response to methanol oxidation. We have also developed methods based around DNA-modified AuNPs, which offer an excellent colorimetric platform for target detection. The DNA density on the surface of modified AuNPs affects enzymatic activity, colloidal stability of AuNPs, the orientation of the probe DNA and its hybridization efficiency. The combination of all these factors ultimately dictates the reaction time and sensitivity of colorimetric assays. We demonstrate the use of DTT as a modulator to control DNA surface coverage on the surface of AuNPs. Using this DTT treatment and a novel probe for exonuclease III activity, we have developed a colorimetric assay based on DTT-treated, DNA-modified AuNPs that can achieve more sensitive and rapid detection of DNA and enzymes relative to existing sensor platforms.

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Feng, Yi. "Printed RFID Humidity Sensor Tags for Flexible Smart Systems". Doctoral thesis, KTH, Industriell och Medicinsk Elektronik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-162152.

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Radio frequency identification (RFID) and sensing are two key technologies enabling the Internet of Things (IoT). Development of RFID tags augmented with sensing capabilities (RFID sensor tags) would allow a variety of new applications, leading to a new paradigm of the IoT. Chipless RFID sensor technology offers a low-cost solution by eliminating the need of an integrated circuit (IC) chip, and is hence highly desired for many applications. On the other hand, printing technologies have revolutionized the world of electronics, enabling cost-effective manufacturing of large-area and flexible electronics. By means of printing technologies, chipless RFID sensor tags could be made flexible and lightweight at a very low cost, lending themselves to the realization of ubiquitous intelligence in the IoT era. This thesis investigated three construction methods of printable chipless RFID humidity sensor tags, with focus on the incorporation of the sensing function. In the first method, wireless sensing based on backscatter modulation was separately realized by loading an antenna with a humidity-sensing resistor. An RFID sensor tag could then be constructed by combining the wireless sensor with a chipless RFID tag. In the second method, a chipless RFID sensor tag was built up by introducing a delay line between the antenna and the resistor. Based on time-domain reflectometry (TDR), the tag encoded ID in the delay time between its structural-mode and antenna-mode scattering pulse, and performed the sensing function by modulating the amplitude of the antenna-mode pulse. In both of the above methods, a resistive-type humidity-sensing material was required. Multi-walled carbon nanotubes (MWCNTs) presented themselves as promising candidate due to their outstanding electrical, structural and mechanical properties. MWCNTs functionalized (f-MWCNTs) by acid treatment demonstrated high sensitivity and fast response to relative humidity (RH), owing to the presence of carboxylic acid groups. The f-MWCNTs also exhibited superior mechanical flexibility, as their resistance and sensitivity remained almost stable under either tensile or compressive stress. Moreover, an inkjet printing process was developed for the f-MWCNTs starting from ink formulation to device fabrication. By applying the f-MWCNTs, a flexible humidity sensor based on backscatter modulation was thereby presented. The operating frequency range of the sensor was significantly enhanced by adjusting the parasitic capacitance in the f-MWCNTs resistor. A fully-printed time-coded chipless RFID humidity sensor tag was also demonstrated. In addition, a multi-parameter sensor based on TDR was proposed.The sensor concept was verified by theoretical analysis and circuit simulation. In the third method, frequency-spectrum signature was utilized considering its advantages such as coding capacity, miniaturization, and immunity to noise. As signal collision problem is inherently challenging in chipless RFID sensor systems, short-range identification and sensing applications are believed to embody the core values of the chipless RFID sensor technology. Therefore a chipless RFID humidity sensor tag based on near-field inductive coupling was proposed. The tag was composed of two planar inductor-capacitor (LC) resonators, one for identification, and the other one for sensing. Moreover, paper was proposed to serve as humidity-sensing substrate for the sensor resonator on accounts of its porous and absorptive features. Both inkjet paper and ordinary packaging paper were studied. A commercial UV-coated packaging paper was proven to be a viable and more robust alternative to expensive inkjet paper as substrate for inkjet-printed metal conductors. The LC resonators printed on paper substrates showed excellent sensitivity and reasonable response time to humidity in terms of resonant frequency. Particularly, the resonator printed on the UV-coated packaging paper exhibited the largest sensitivity from 20% to 70% RH, demonstrating the possibilities of directly printing the sensor tag on traditional packages to realize intelligent packaging at an ultra-low cost.

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25

Skedung, Lisa. "Tactile perception : role of physical properties". Licentiate thesis, Stockholm : Skolan för kemivetenskap, Kungliga Tekniska högskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11891.

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Baldé, Mamadou Saliou. "Etude et développement de microtechnologies sur substrat papier : application à la structuration d'AL2O3 poreux pour la faisabilité d'un capteur d'humidité". Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20065.

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L'objectif premier de ce projet est la mise au point de procédés de fabrication microélectroniques/microtechnologiques compatibles avec l'utilisation d'un support papier. Pour cela, des techniques comme l'évaporation thermique sous vide, la photolithographie, l'électrodéposition et l'anodisation d'aluminium ont été développées et adaptées à ce support. Des bancs de caractérisations structurels, électriques et flexibles ont été aussi mis en œuvre pour étudier la fiabilité des couches déposées sur un tel substrat. En application, un capteur d'humidité à base d'oxyde d'aluminium flexible a été fabriqué et les tests en humidité ont montré d'excellents résultats permettant de valider le travail effectué
The primary objective of this project is the implementation of microelectronics/microtechnology processes compatible with the use of paper-based substrate. For this purpose, techniques such as thermal vacuum evaporation, photolithography, electroplating and anodizing aluminum have been developed and adapted to this substrate. Structural, electrical and flexible characterizations benches have also been implemented to study the reliability of the layers deposited on such substrate. A moisture sensor based on flexible aluminum oxide was made and humidity tests have shown excellent results which validate the work

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27

Chindondo, Peregrino. "O papel da Informação e da Tecnologia na gestão da prevenção de conflitos". Master's thesis, Academia Militar. Direção de Ensino, 2013. http://hdl.handle.net/10400.26/6811.

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Os actuais modelos de prevenção estratégica de conflitos, na perspectiva analisada neste estudo, estão com algumas excepções, associados a instituições dos serviços de informações dos Estados ou afins, que facilmente são negligenciáveis, à medida que o papel dessas pessoas de bem se torna cada vez menos interventivo e os seus actores comprometidos em altas esferas de abordagem multilateral. Gerir a prevenção de conflitos através de um sistema de informação e tecnologia, é uma pesquisa académica baseada em diversas teorias e práticas de informação e do conhecimento. Além disso, apresenta uma proposta sobre a componente tecnológica, através da criação de um Centro Digital de Alerta (CDA) para a colheita e processamento sistemático de informação conflituosa, adaptado a modelos culturais e históricos, de gestão pública e privada de informação, aplicável em Angola. Designado por BTIP (Banco Tecnológico de Informações Preventivas) e fazendo parte do Sistema Nacional de Gestão e Prevenção de Conflitos (SNGPC), o Centro pretende ser uma plataforma digital complementar em aplicação de sistemas e novas tecnologias de informação. Há que multiplicar e valorizar todas as possíveis capacidades de prevenção face às sociedades modernas, cuja regra é a conflitualidade, por causa da pluralidade, disponibilidade e intensidade de escolhas em informação. Eis uma proposta auto-sustentável em segurança, preservação e desenvolvimento humano. É também uma questão de gestão estratégica em economia de recursos, saúde pública e empreendedorismo comunitário.
ABSTRACT The current conflict prevention models, in the perspective of this study, they are with some exceptions, associated to the State intelligence services or linked, which become neglected while this bonna fide entities role become less and less intervening and their actors compromised at the higher levels of the multi-lateral approaches. Managing conflict prevention by an information and technology system, it is an academic research based upon various theories and practices on information and knowledge. Furthermore, it brings at our attention a technological proposal, by the creation of a digital centre for a systematic gathering and processing of conflict data, adaptable to the current Angolan cultural and historical public and private management information models. Under the name TPIB (Technological Preventive Information Bank) and as part of the National Conflict and Prevention Management System (NCPMS), this Centre it is aimed at becoming a complementary digital platform in the use of new information and technological systems. There is a need for a multiplier and value effort for all the possible prevention capacities facing modern societies, which have the conflict as a rule, due to the diversity, availability and intensity of existing choices on information. This is a self-sustainable proposal on security, preservation and human development. It is as well a matter of strategy in resources economy, public health and the empowerment for communities.

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28

Fastier-Wooller, Jarred W. "Innovative Tactile Sensing Systems for Robotic Applications". Thesis, Griffith University, 2022. http://hdl.handle.net/10072/413983.

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Tactile sensing is essential to the way humans and robots physically interact with the world. Humans use a complex system of nerves to touch and feel their surroundings. Researchers are attempting to achieve the same for robotics by studying and improving tactile sensing systems. Notably, tactile sensing for anthropomorphic robotics is of ongoing interest in homecare/ assistant, culinary, agriculture, and medical areas. The contribution to the development of tactile feedback systems can aid in advancing these robotic systems, allowing for more complex tasks to be performed. However, many of the available tactile sensing systems are currently very expensive and not practical for use in education and areas without access to expensive equipment. The price and complexity of available tactile sensing systems are currently challenging problems. This project investigates and explores sensing mechanisms, sensor structures, and fabrication methods to develop and evaluate several low-cost and accessible tactile sensors. Introducing novel designs and implementations of low-cost tactile sensors may bring more robotic systems closer to public application, positively affecting the funding and development of robotic advancements. Sequential implementation of varying materials and methods is performed to balance cost and complexity. This thesis reports: (1) An ultra low-cost graphite on paper sensor boasting an incredibly high response rate; (2) A low-cost and soft ionic liquid filled sensor capable of discerning directional pressures and temperature; (3) An easily integrable and flexible multifunctional pressure and temperature sensor; (4) A low-cost and easily integrable, flexible, and highly versatile multimodal pressure sensor. Evaluation of tactile sensing performance in robotic grippers successfully demonstrates the potential for these sensors in practical applications. This work has introduced and diversified existing technologies in robotic tactile sensing, improving the overall understanding and effectiveness of the materials and processes reported within. Presented works show the feasibility for ongoing research in areas that have been tapped into, furthering the development of smart and highly reliable low-cost tactile sensors.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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Hayashi, Roberto Kenji. "Desenvolvimento de um sensor de baixo custo e descartável para o monitoramento de odor". Universidade Federal de São Carlos, 2015. https://repositorio.ufscar.br/handle/ufscar/7222.

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The research proposal was found low cost alternative solution to automatize the classification and selection process to recognize fruit ripeness level using biologic behavior instead of human visual inspection. The goal was to develop low cost and disposable solid state sensor made of office paper with respective equipment for odor monitoring. The concept used to development this sensor was replace the interdigitated electrode with a conductive track using office paper impregnated with an electrolyte that "turns" cellulose fiber in an electrical conductor under gas action. In order to get gas adsorbing surface property for odor monitoring were tested some electrolytes like: Magnesium Chloride, Potassium Iodide, Calcium Hydroxide and others. This configuration replaced the interdigitated electrode per cellulose fiber doped with an electrolyte, it´s the originality of this research. In the fruit ripening process, the major enzymes involved are pectinase to crack the cell walls responsible for the fruits softening, amylase which degrades carbohydrates to simple sugars responsible for the flavor and hydrolase which reduces the amount of chlorophyll responsible for the fruit color change. The reaction that produces ethylene gas (C2H4) is lipids oxidation, the main gas exhaled during the fruits ripening process. The equipment adopted to pick up electrical signal is based on resistance and capacitance measuring that showed reversible electrical signal variation basically due the track geometry and cellulose fiber doping with an electrolyte. Another feature found was the office paper sensor decrease resistivity with fruit odors presence. The sensor manufacturing process is simple, basically consist in printing a mask with a negative image of the track by laser printing and office paper impregnation by an electrolyte.
A proposta da pesquisa foi buscar uma alternativa de baixo custo para automatizar o processo de seleção e classificação do nível de maturação da banana, utilizando-se do reconhecimento de gás exalado no processo de maturação via biológica, em vez da inspeção visual humana. O objeto da pesquisa foi desenvolver um sensor de estado sólido, de baixo custo e descartável, à base de papel sulfite, com o seu respectivo equipamento de monitoramento de odor. O conceito utilizado no desenvolvimento do sensor foi eliminar o eletrodo condutor interdigitado e substitui-lo por uma trilha condutora via dopagem do papel sulfite, impregnando com um eletrólito que “transforma” a fibra de celulose em um condutor elétrico sob a ação de gás. Visando conferir a propriedade de adsorção superficial dos gases no processo de monitoramento de odor, foram testados os seguintes eletrólitos: Cloreto de Magnésio, Iodeto de Potássio, Hidróxido de Cálcio entre outros. Essa configuração de substituir o eletrodo interdigitado por fibra de celulose dopada com um eletrólito traduz a originalidade desta pesquisa. No processo de amadurecimento das frutas, as principais enzimas envolvidas foram: pectinase, que quebra as paredes celulares, responsável pelo amolecimento das frutas; amilase, que degrada carboidratos em açúcares simples, responsável pelo sabor e a hidrolase, que reduz a quantidade de clorofila responsável pela mudança de cor da fruta. A reação que produz o gás etileno (C2H4) é a oxidação de lipídios, principal gás exalado durante o processo de amadurecimento das frutas. O equipamento de captação de sinal elétrico do sensor de estado sólido foi baseado na medição de resistência e capacitância, que apresentou variação de sinal elétrico reversível, basicamente em função da geometria da trilha e da dopagem da fibra de celulose com um eletrólito. Outra característica do sensor de papel sulfite foi a queda da resistividade com a presença de odores da fruta. O processo de fabricação do sensor é simples: consiste basicamente em uma impressão a laser de uma máscara com imagem negativa da trilha e a impregnação do papel sulfite com um eletrólito.

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Crivellaro, Fernando Sacilotto. "Estudo e desenvolvimento de sistema baseado em sensores de pressão aplicados à ortodontia". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/157806.

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Este trabalho tem por objetivo o estudo e o desenvolvimento de uma solução de engenharia para o mapeamento e caracterização da oclusão dentária, não somente no âmbito de sua distribuição ao longo da arcada, mas também através da mensuração da intensidade de pressão nos pontos de contato oclusal interarco. Neste sentido, empregaram-se esforços no aprofundamento do conhecimento neste campo da Odontologia, assim como, na elaboração de um sistema experimental que, utilizando sensores de pressão/força resistivos (FSR) específicos para uso odontológico, viabilizou a análise do estado da oclusão, atuando como agente facilitador no diagnóstico de desequilíbrios oclusais. Inicialmente, são apresentados e esclarecidos os principais conceitos da esfera odontológica, os quais são tomados como base para todos os projetos deste trabalho, além da abordagem referente às formas de contato entre os dentes, aos diferentes tipos de oclusão e seus problemas. Em relação ao desenvolvimento do sistema, foram projetadas duas placas de circuito impresso para interface com os sensores e elaborados o firmware de acesso ao hardware, assim como o software de gerenciamento global do sistema. Todos os blocos do circuito de condicionamento foram avaliados e as suas funcionalidades validadas. Do mesmo modo, a caracterização da resposta dos sensores e a sua homogeneidade ao longo da extensão sensível foram analisadas, demonstrando que a resistência elétrica varia de forma análoga em todas as áreas do sensor. Através de ensaios realizados com sujeito envolvido no projeto, estabeleceu-se um comparativo entre a utilização do papel carbono e o sistema desenvolvido, mostrando as vantagens na utilização do segundo, principalmente atreladas à capacidade de avaliação da intensidade dos contatos oclusais. Por fim, ainda se valendo do uso paralelo do papel carbono, foram efetuados ensaios de análise da oclusão em sujeito envolvido no projeto utilizando placa miorrelaxante, possibilitando a utilização da capacidade do sistema desenvolvido para executar ajustes precisos na placa, com a finalidade de manter o balanço de pressões oclusais entre ambos os lados da arcada.
This essay has as objective the study and development of an engineer solution for the dental occlusion mapping and characterization, not only related to the interarch occlusal contact distribution, but also through the pressure magnitude measuring in each. In this sense, was employed effort in the Odontological knowledge increasing and also in the system elaboration allowing the occlusion state evaluation and acting as an easier agent in the occlusion disturbs diagnosing using a specific pressure/force sensing resistor (FSR) for dental use. Initially the main concepts of the Odontological sphere are presented, clarified and took as a base for all the projects in this essay. Besides this, different teeth contacts shapes are shown, as well as the occlusion’s types and its problems. In the system development, two printed circuit boards were designed for sensor interfacing. The hardware access through the firmware was elaborated, even as the global system managing software. All the conditioning circuit blocks and functionalities were evaluated and validated. In the same way, the sensor’s output and its homogeneity through all the sensible extension were evaluated, showing that the sensor’s electric resistance changes in the same form in all the sensor’s areas. In addition, it was showed the advantages of the developed system over the articulation paper through trials with a subject that is part of the project, showing the capacity of the system in the occlusion contacts magnitude evaluation. Ultimately, also in an articulation paper versus the developed system comparison, it was made occlusion analysis trials with subject using a night guard for teeth grinding (bruxism), showing the system capacity of precisely adjust the night guards for pressure balance between the both arch sides.

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Holmqvist, Johan. "Development of Free-Standing Interference Films for Paper and Packaging Applications". Thesis, Linköping University, The Department of Physics, Chemistry and Biology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11398.

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The newfound capability of creating moisture sensitive interference multilayered thin films (MLTFs) comprising microfibrillated cellulose and polymers has not previously been possible to implement on surfaces other than silicon wafer strips. Being able to incorporate interference MLTFs on fibre-based materials would introduce the possibility for new applications within authentication, sensing and customer attraction for the paper and packaging industry. By using trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane we were able to hydrophobically modify silicon substrates, enabling interference MLTF lift-off and thus the creation of free-standing MLTFs of approximately 400 nm thickness. Contact dried MLTFs approximately 250 nm thick, were successfully transferred to copy- and filter paper as well as to cellulose-based dialysis membranes. We can also report on the successful synthesis of interference MLTFs directly on a fibre composite material and on aluminium. Initial tests of a method to quantify the pull-off conditions of the MLTFs from the fluorinated surfaces using the Micro Adhesion Measurement Apparatus showed promising results.

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Almeida, Bruno Augusto Teixeira de. "O Desempenho dos voluntários e profissionais na organização de eventos desportivos internacionais : O Papel das relações humanas". Master's thesis, Instituições portuguesas -- UP-Universidade do Porto -- -Faculdade de Ciências do Desporto e de Educação Física, 2001. http://dited.bn.pt:80/29313.

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Dissertação de Mestrado em Ciência do Desporto, área de especialização em Gestão Desportiva, apresentada à Faculdade de Ciências do Desporto e de Educação Física da Universidade do Porto
Os grandes eventos desportivos internacionais, são dos projectos mais complexos a ter em consideração para o próximo século, sobretudo devido à sua dimensão e pelo facto de envolverem inúmeros recursos humanos para a sua execução.As questões relacionadas com o envolvimento e compromisso por parte dos recursos humanos participantes, tornam-se por isso essenciais para um correcto desenrolar do evento. Assim:O envolvimento em regime de voluntariado ou profissional não condiciona a percepção do sucesso da organização do evento desportivo ?Através de um questionário, avaliou-se a percepção do sucesso e envolvimento dos recursos humanos na organização de eventos desportivos. A amostra constou de 80 pessoas que participaram na organização do VI Campeonato Mundial Universitário de Futebol de 5 (1998) e no Campeonato Mundial de Voleibol Escolar ISF 2000.O questionário foi ministrado aos dois grupos estratégicos (voluntários e profissionais) considerados no estudo, que desempenharam tarefas na estrutura organizativa do evento desportivo.A conclusão a que se chegou foi que, apesar de existirem diferenças na percepção do sucesso e envolvimento dos voluntários e profissionais, ambos consideram que o envolvimento e interacção pessoal é fundamental para o seu comprometimento com o evento.

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33

Almeida, Bruno Augusto Teixeira de. "O Desempenho dos voluntários e profissionais na organização de eventos desportivos internacionais : O Papel das relações humanas". Master's thesis, Universidade do Porto. Reitoria, 2001. http://hdl.handle.net/10216/10012.

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Dissertação de Mestrado em Ciência do Desporto, área de especialização em Gestão Desportiva, apresentada à Faculdade de Ciências do Desporto e de Educação Física da Universidade do Porto
Os grandes eventos desportivos internacionais, são dos projectos mais complexos a ter em consideração para o próximo século, sobretudo devido à sua dimensão e pelo facto de envolverem inúmeros recursos humanos para a sua execução.As questões relacionadas com o envolvimento e compromisso por parte dos recursos humanos participantes, tornam-se por isso essenciais para um correcto desenrolar do evento. Assim:O envolvimento em regime de voluntariado ou profissional não condiciona a percepção do sucesso da organização do evento desportivo ?Através de um questionário, avaliou-se a percepção do sucesso e envolvimento dos recursos humanos na organização de eventos desportivos. A amostra constou de 80 pessoas que participaram na organização do VI Campeonato Mundial Universitário de Futebol de 5 (1998) e no Campeonato Mundial de Voleibol Escolar ISF 2000.O questionário foi ministrado aos dois grupos estratégicos (voluntários e profissionais) considerados no estudo, que desempenharam tarefas na estrutura organizativa do evento desportivo.A conclusão a que se chegou foi que, apesar de existirem diferenças na percepção do sucesso e envolvimento dos voluntários e profissionais, ambos consideram que o envolvimento e interacção pessoal é fundamental para o seu comprometimento com o evento.

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34

Pokpas, Keagan William. "Microfluidic graphenised-paper electroanalytical devices (μGPED) for adsorptive cathodic stripping voltammetric detection of metal contaminants". University of the Western Cape, 2017. http://hdl.handle.net/11394/5506.

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Philosophiae Doctor - PhD
The need for clean, non-toxic drinking water supplies, free of pollutants and metal contamination is vital in impoverished areas and the developing world alike. With this in mind, the development of accurate, inexpensive, portable and simple devices for remote sensing applications is therefore pivotal for early detection and the prevention of illnesses. Over the last two decades, adsorptive stripping voltammetry (AdSV) has emerged as a superior detection method over common analytical techniques due to its low-cost instrumentation, unskilled labour and ability to detect a wide range of analytes.
2020-08-31

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Larsson, Jonathan. "PH-MÄTNING I PAPPERSPRODUKTION : En studie i optimeringar av elektriska mätsystem". Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184577.

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Den fundamentala principen för tillverkning av papper är inte en särskilt komplicerad sådan. Men för att pappret skall erhålla specifika egenskaper blir processen alltmer komplicerad. Bland annat tillsätts olika typer av kemikalier och processen övervakas ständigt av olika system. Ett av dessa system mäter pH-halten i pappersmassan. Mätsystemet är dock utsatt för frekventa mätfel vilket medför en felaktig dosering av den koldioxid som används för att sänka pH-värdet. Detta kan slutligen ha negativ påverkan på papprets egenskaper. Syftet bakom arbetet är att mätsystemet ska bidra till en jämn reglering av pH och därigenom garantera jämn papperskvalitet. För detta arbete har en frågeställning och ett antal mål och delmål etablerats. De övergripande målen omfattar att etablera en statistisk modell över mätfel och beräkna eventuella ekonomiska besparingar. För att uppfylla mål och besvara frågeställningen måste en grunduppfattning byggas uppför berörda delar av tillverkningsprocessen, pH-värdets påverkan i processen, pH-sensorns mätprincip, mätsystemets utformning och rutiner som berör mätsystemet. Med denna grund undersöks uppkomsten av mätfel för de sex mätpunkterna. Detta utförs med två tillvägagångssätt: Sammanställning av lagrade historiska data och sammanställningar avprovtagningar utförda under kontrollerade förhållanden. De aspekter som undersöks är magnitud, frekvens och hur dessa förhåller sig till olika processrelaterade värden. En kalkyl för kostnader berörande mätsystemet upprättas även. Denna omfattar aktuella kostnader för koldioxid och underhåll. I resultatet presenteras en statistisk modell över mätfel, uppdelat på historiska och i närtid. Den historiska modellen visar, för samtliga behandlade positioner, en medelavvikelse på <0,3 pH-enheter. Den min- och maximala avvikelsen kan däremot uppgå till >0,8 pH-enheter. Modellen för närtid visar på kraftiga avvikelser för fyra av de sex behandlade systempositionerna, som relaterar både till papperskvalitet och ytvikt. Denna statistiska modell används sedan för att beräkna möjliga besparingar. Här påvisades att viss besparing fanns, både för koldioxid och för underhållskostnader. Slutsatsen för detta arbete är att ett mätfel existerar för majoriteten av de behandlade positionerna. Det har även kunnat påvisas ett samband med de undersökta processrelaterade aspekterna, men resultatet kan inte garanteras fullständigt. Med detta kunde även en möjlig besparing av koldioxid uppskattas vid bättre mätnoggrannhet. Besparingen uppgick till c:a 200 tkr, vilket i jämförelse med företagets omsättning endast utgör 0,075‰ av denna.
The fundamental principle for manufacturing paper is not a complicated one. However, for the paper to acquire specific properties, the process becomes increasingly complicated.Among other things, different chemicals are added, and the process is continuouslymonitored by various systems. One of these systems measures the pH-level of the pulp. This system is however constantly affected by measuring errors, which in turn leads to the incorrect dosage of the carbon dioxide used to lower the pH-level. This could in turn have a negative impact on the properties of the final paper. The underlaying purpose of this project is for the measuring system to ensure an even regulation of pH and therethrough guarantee an even paper quality. For this project, several question at issue, goals and subgoals have been established. The general goals cover establishing a statistical model for the error and estimate possible economical savings. To fulfil the goals and answer the questions at issue, firstly a basic understanding must be established for: concerned parts of the manufacturing process, the effect pH-level has on the process, the measuring principle of the pH-sensor, the design of the measuring systemand the routines concerning the measuring system. With this basis, the occurrence of measuring error is examined for the six measuring points. This is accomplished with two methods: The compilation of historical data and the compilation of manual measurementsexecuted under controlled conditions. The aspects examined are magnitude, frequency and the relation to process related values. Finally, a calculation for costs regarding the measuring system was established. This includes current carbon dioxide and maintenance costs. The result presents a statistical model for the measuring error, divided into historical and near time. The historical model shows that for all the addressed positions, a mean deviation occurred <0.3 pH-units. However, the minimum and maximum deviation could reach >0.8 pH-units. The model for near time shows significant deviations for four out of the six covered positions, which in turn shows relations to both paper quality and surface weight. With this statistical model possible savings were calculated. This in turn showed the possibility of savings for both carbon dioxide and maintenance. The conclusion for this project is the existence of a measuring error. Also, a connection between this and the process related aspects could be established. Although, the result cannot be completely guarantied. With this, possible savings through better accuracy could be estimated. Though, these were only in the size of 0.075‰ of the company’s total revenue.

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Moura, Glenda Miranda. "Cantar A palo seco: o papel do intérprete na geração do sentido na canção". www.teses.ufc.br, 2014. http://www.repositorio.ufc.br/handle/riufc/9699.

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MOURA, Glenda Miranda. Cantar A palo seco: o papel do intérprete na geração do sentido na canção. 2014. 76f. – Dissertação (Mestrado) – Universidade Federal do Ceará, Departamento de Letras Vernáculas, Programa de Pós-graduação em Linguística, Fortaleza (CE), 2014.
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In this dissertation, we objectify to analyze the part played by the singer in the process of generating senses in the song. For that propose, we analyzed four cover versions of the song A palo seco, composed by Belchior, in the intend of noticing which elements are used to actualize the senses only virtualized in the lyric. To the study and analisis of songs as syncretic texts we adopted the Semiotic of Song developed by Luiz Tatit (2008, 2011) from Greimas Semiotics, as well as the further contributions of Dietrich (2004), Carmo Jr (2005), Coelho (2007) and Machado (2012). Our analysis shows that the singer can actualise the senses from different ways and all the elements that make a song (from the human voice to the instruments voice) take part in the process or generating senses, but in the universe of songs analyzed, the singer who was shown to approaches the senses in the lyrics is Oswaldo Montenegro, mainly because of the passionalization he puts in the melody.
Este trabalho tem como objetivo analisar o papel do intérprete na geração de sentidos da canção. Para tanto, foram analisadas quatro versões de A palo seco e comparadas à versão do compositor Belchior, a fim de perceber que elementos os intérpretes mobilizam para realizar os sentidos virtualizados na letra. Para o estudo e a análise da canção enquanto texto sincrético, adotamos o aporte teórico-metodológico da Semiótica da Canção, desenvolvida por Luiz Tatit (2008, 20011), e o da Semiótica Discursiva, de origem greimasiana. Apoiamo-nos igualmente nas contribuições de Dietrich (2004), Carmo Jr. (2005) e Coelho (2007) para discutir os modos de existência semiótica da canção, bem como o papel gerador de sentidos exercido pelos instrumentos musicais, e nas de Machado (2012) para a compreensão do gesto enunciativo do intérprete. Nossos resultados mostram que, do universo analisado, o intérprete que mais se aproxima de um cantar a palo seco é Oswaldo Montenegro, o que se justifica principalmente pela passionalização que o cancionista imprime na melodia da canção. Porém, é válido notar que o intérprete pode realizar os sentidos virtualizados na letra da canção de diferentes maneiras e que todos os elementos que compõem a peça cancional (da voz humana à voz dos instrumentos) atuam no processo de geração e integralização desses sentidos.

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37

Vivancos, Prellezo Ana. "Papel de la peroxirredoxina Tpxl y del factor de trascripción Pap1 en la respuesta a H2O2 en Schizossaccharomyces pombe". Doctoral thesis, Universitat Pompeu Fabra, 2006. http://hdl.handle.net/10803/7091.

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La vida aeróbica conlleva la formación de especies reactivas derivadas del oxígeno: el radical hidroxilo (OH·), el ión superóxido (O2·-) y el peróxido de hidrógeno (H2O2). En Schizosaccharomyces pombe, dos rutas controlan las respuestas antioxidantes en respuesta a estrés oxidativo por H2O2: la del factor de transcripción Pap1 y la de la MAP quinasa Sty1.
En esta tesis doctoral, hemos determinado que la activación de Pap1 se da en respuesta a dosis moderadas, pero no severas, de H2O2. Hemos identificado a la peroxirredoxina Tpx1 como sensor y transmisor de la señal de estrés oxidativo a Pap1. La inactivación temporal de Tpx1, durante estrés oxidativo severo, por oxidación a sulfínico de su cisteína catalítica inhibe la transmisión de señal a Pap1. En dichas condiciones, se activa la ruta de Sty1, que media la inducción de Srx1, cuya función es reducir y, con ello, reactivar a Tpx1. Finalmente, hemos estudiado el papel esencial de Tpx1 en aerobiosis.
Aerobic life involves formation of reactive oxygen species: hydroxyl radical (OH·), superoxide ion (O2·-) and hydrogen peroxide (H2O2). In Schizosaccharomyces pombe, two pathways respond to H2O2 and trigger independent antioxidant-gene responses: the Pap1 and the Sty1 pathways.
In this thesis project, we have determined that the activation of the transcription factor Pap1 occurs only at low, but not elevated, H2O2 concentrations. We have identified the peroxiredoxin Tpx1 as a H2O2-sensor and redox activator of Pap1. The temporal inactivation of Tpx1 during severe oxidative stress, by oxidation of its catalytic cysteine to sulfinic acid, inhibits signal transduction to Pap1. During these conditions, the MAP kinase Sty1 is activated and expression of the sulfiredoxin Srx1 is triggered. Srx1 functions to reduce and thus reactivate Tpx1. Finally, we have analysed the essential function of Tpx1 in aerobiosis.

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Moura, Glenda Miranda. "Cantar A palo seco: o papel do intÃrprete na geraÃÃo do sentido na canÃÃo". Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=12811.

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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Este trabalho tem como objetivo analisar o papel do intÃrprete na geraÃÃo de sentidos da canÃÃo. Para tanto, foram analisadas quatro versÃes de A palo seco e comparadas Ã versÃo do compositor Belchior, a fim de perceber que elementos os intÃrpretes mobilizam para realizar os sentidos virtualizados na letra. Para o estudo e a anÃlise da canÃÃo enquanto texto sincrÃtico, adotamos o aporte teÃrico-metodolÃgico da SemiÃtica da CanÃÃo, desenvolvida por Luiz Tatit (2008, 20011), e o da SemiÃtica Discursiva, de origem greimasiana. Apoiamo-nos igualmente nas contribuiÃÃes de Dietrich (2004), Carmo Jr. (2005) e Coelho (2007) para discutir os modos de existÃncia semiÃtica da canÃÃo, bem como o papel gerador de sentidos exercido pelos instrumentos musicais, e nas de Machado (2012) para a compreensÃo do gesto enunciativo do intÃrprete. Nossos resultados mostram que, do universo analisado, o intÃrprete que mais se aproxima de um cantar a palo seco Ã Oswaldo Montenegro, o que se justifica principalmente pela passionalizaÃÃo que o cancionista imprime na melodia da canÃÃo. PorÃm, Ã vÃlido notar que o intÃrprete pode realizar os sentidos virtualizados na letra da canÃÃo de diferentes maneiras e que todos os elementos que compÃem a peÃa cancional (da voz humana Ã voz dos instrumentos) atuam no processo de geraÃÃo e integralizaÃÃo desses sentidos.
In this dissertation, we objectify to analyze the part played by the singer in the process of generating senses in the song. For that propose, we analyzed four cover versions of the song A palo seco, composed by Belchior, in the intend of noticing which elements are used to actualize the senses only virtualized in the lyric. To the study and analisis of songs as syncretic texts we adopted the Semiotic of Song developed by Luiz Tatit (2008, 2011) from Greimas Semiotics, as well as the further contributions of Dietrich (2004), Carmo Jr (2005), Coelho (2007) and Machado (2012). Our analysis shows that the singer can actualise the senses from different ways and all the elements that make a song (from the human voice to the instruments voice) take part in the process or generating senses, but in the universe of songs analyzed, the singer who was shown to approaches the senses in the lyrics is Oswaldo Montenegro, mainly because of the passionalization he puts in the melody.

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39

JÃnior, JerÃnimo Junqueira. "Efeito gastroprotetor da amifostina (ETHYOLÂ) na lesÃo gÃstrica induzida por etanol em ratos: papel dos grupos sulfidrÃlicos nÃo-protÃicos e neurÃnios sensoriais aferentes". Universidade Federal do CearÃ, 2008. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1306.

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INTRODUÃÃO: A amifostina (WR-2721) tem sido largamente estudada como agente citoprotetor em diferentes ÃrgÃos e contra os mais diversos agressores do organismo humano. Recentemente, um efeito gastroprotetor deste fÃrmaco foi observado em modelo de lesÃo gÃstrica induzida por indometacina (MOTA et al., 2007). OBJETIVOS: Este trabalho investigou o efeito da amifostina na lesÃo gÃstrica por etanol e o papel dos neurÃnios sensoriais aferentes, grupos sulfidrÃlicos nÃo-protÃicos, Ãxido nÃtrico, canais de potÃssio sensÃveis ao ATP e ciclooxigenase-2 nesse processo. MÃTODOS: Ratos Wistar foram tratados com amifostina (22,5, 45, 90 ou 180 mg/kg, v.o. ou s.c.). ApÃs 30 minutos, os animais receberam etanol absoluto (5 ml/kg v.o.). Decorridos 60 minutos da administraÃÃo de etanol, os animais foram sacrificados. Foram realizados estudos macroscÃpicos e histolÃgicos, bem como dosagem de grupos sulfidrÃlicos nÃo-protÃicos e de hemoglobina em fragmentos de estÃmago. Outros grupos foram prÃ-tratados com L-NAME (10 mg/kg i.p.), glibenclamida (10 mg/kg v.o.), celecoxibe (10 mg/kg v.o.) ou salina. ApÃs 30 minutos os ratos receberam amifostina (90 mg/kg v.o. ou s.c.) e depois de mais 30 minutos etanol absoluto (5 ml/kg), com sacrifÃcio ocorrendo 60 minutos depois. Um grupo de animais foi desensibilizado com capsaicina (125 mg/kg s.c.) entre 10 a 14 dias antes do protocolo de tratamento com amifostina. RESULTADOS: A amifostina preveniu de forma significativa o dano macroscÃpico causado por etanol no estÃmago nas doses de 45, 90 e 180 mg/kg quando administrada por via oral e 90 e 180 mg/kg quando utilizada por via subcutÃnea. Os parÃmetros histolÃgicos, edema, hemorragia e perda de cÃlulas epiteliais, tambÃm foram reduzidos (p<0,05) com o uso de amifostina. Os animais que receberam apenas etanol apresentaram nÃveis reduzidos de GSH no estÃmago. A amifostina reverteu esse efeito atravÃs de um estÃmulo Ã produÃÃo de novo de GSH ou pela prevenÃÃo do consumo destes grupos. A gastroproteÃÃo da amifostina na lesÃo induzida pelo etanol foi revertida pela administraÃÃo prÃvia de doses neurotÃxicas de capsaicina, mas nÃo pelo uso de L-NAME, glibenclamida ou celecoxibe. CONCLUSÃES: A amifostina protege a mucosa gÃstrica contra a injÃria induzida pelo etanol atravÃs de um aumento dos nÃveis de GSH e estimulaÃÃo de neurÃnios sensoriais aferentes no estÃmago. Esse efeito parece ser independente da ativaÃÃo de canais de potÃssio sensÃveis ao ATP e da atividade de Ãxido nÃtrico sintase e ciclooxigenase-2
INTRODUCTION: Amifostine (WR-2721) has been widely tested as a cytoprotective agent against a number of aggressors in different organs. Recently, a gastroprotective effect was observed for this drug in a model of indomethacin-induced gastric injury (MOTA et al., 2007). OBJECTIVES: We investigated the effect of amifostine on ethanol-induced gastric injury and the role played by afferent sensory nerves, non-protein sulfhydryl groups, nitric oxide, ATP-sensitive potassium channels and cyclooxygenase-2 in the mechanism. METHODS: Wistar rats were treated with amifostine (22.5, 45, 90 or 180 mg/kg, p.o. or s.c.). Thirty minutes after amifostine administration, the animals were given 100% ethanol (5 ml/kg p.o.). Sixty minutes after ethanol administration the animals were euthanized. Macroscopic and histological studies were carried out and stomach fragments were retrieved and submitted to analysis for non-protein sulfhydryl groups and hemoglobin. Some animals were pretreated with L-NAME (10 mg/kg i.p.), glibenclamide (10 mg/kg p.o.), celecoxib (10 mg/kg p.o.) or saline solution. Thirty minutes after pretreatment the animals were given amifostine (90 mg/kg p.o. or s.c.) and, after another 30 minutes, 100% ethanol (5 ml/kg). The animals were euthanized 60 minutes later. Other rats were desensitized with capsaicin (125 mg/kg s.c.) 10-14 days before amifostine treatment. RESULTS: Amifostine treatment significantly reduced ethanol-induced macroscopic stomach injury at 45, 90 and 180 mg/kg p.o. and at 90 and 180 mg/kg s.c. The histological parameters (edema, hemorrhage and epithelial cell loss) were also reduced (p<0.05) when the animals were treated with amifostine. Animals receiving ethanol only presented reduced GSH levels in the stomach. Amifostine reverted this effect either by stimulating de novo GSH production or by preventing the consumption of GSH. Amifostine-promoted gastroprotection against ethanol-induced stomach injury was reversed by pretreatment with neurotoxic doses of capsaicin, but not by L-NAME, glibenclamide or celecoxib. CONCLUSIONS: Amifostine protects against ethanol-induced gastric injury by increasing GSH levels and stimulating the afferent sensory nerves in the stomach independently of ATP-sensitive potassium channels activation, nitric oxide synthase and cyclooxygenase-2 activity

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Skedung, Lisa. "Tactile Perception : Role of Friction and Texture". Doctoral thesis, KTH, Yt- och korrosionsvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-103916.

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Tactile perception is considered an important contributor to the overall consumer experience of a product. However, what physical properties that create the specifics of tactile perception, are still not completely understood. This thesis has researched how many dimensions that are required to differentiate the surfaces perceptually, and then tried to explain these dimensions in terms of physical properties, by interconnecting human perception measurements with various physical measurements. The tactile perception was assessed by multidimensional scaling or magnitude estimation, in which methods human participants assign numbers to how similar pairs of surfaces are perceived or to the relative quantity of a specified perceptual attribute, such as softness, smoothness, coarseness and coolness. The role of friction and surface texture in tactile perception was investigated in particular detail, because typically tactile exploration involves moving (at least) one finger over a textured surface. A tactile approach for measuring friction was developed by means of moving a finger over the surfaces, mounted on a force sensor. The contribution of finger friction to tactile perception was investigated for surfaces of printing papers and tissue papers, as well as for model surfaces with controlled topography. The overarching research goal of this thesis was to study, systematically, the role of texture in tactile perception of surfaces. The model surfaces displayed a sinusoidal texture with a characteristic wavelength and amplitude, fabricated by surface wrinkling and replica molding techniques. A library of surfaces was manufactured, ranging in wavelengths from 270 nm up to 100 µm and in amplitudes from 7 nm up to 6 µm. These surfaces were rigid and cleanable and could therefore be reused among the participants. To my knowledge, this is the first time in a psychophysical experiment, that the surface texture has been controlled over several orders of magnitude in length scale, without simultaneously changing other material properties of the stimuli. The finger friction coefficient was found to decrease with increasing aspect ratio (amplitude/wavelength) of the model surfaces and also with increasing average surface roughness of the printing papers. Analytical modeling of the finger’s interaction with the model surfaces shows how the friction coefficient increases with the real contact area, and that the friction mechanism is the same on both the nanoscale and microscale. The same interaction mechanism also explains the friction characteristics of tissue paper. Furthermore, it was found that the perceptions of smoothness, coarseness, coolness and dryness are satisfactorily related to the real contact area at the finger-surface interface. It is shown that it is possible to discern perceptually among both printing papers and tissue papers, and this differentiation is based on either two or three underlying dimensions. Rough/smooth and thin/thick were the two main dimensions of surface feel found for the printing papers, whereas friction and wavelength were strongly related to the perceptual cues employed in scaling the model surfaces. These experimental results support the duplex theory of texture perception, which holds that both a “spatial sense”; used to discriminate the roughest textures from the others, and a “vibration sense”; used to discriminate among the smoother textures, are involved. The perception of what is considered rough and smooth depends on the experimental stimulus context. It is concluded that friction is important for human differentiation of surface textures below about 10 µm in surface roughness, and for larger surface textures, friction is less important or can even be neglected. The finger friction experiments also allowed the following conclusions to be drawn: (i) The interindividual variation in friction coefficients is too large to allow direct comparison; however, the trends in relative friction coefficients for a group of participants are the same. (ii) Lipids are transferred to the test surface of study, and this lowers the friction. (iii) Many of the studies point to a characteristic frequency during sliding of about 30 Hz, which is both characteristic of the resonance frequency of skin and the expected frequency associated with the fingerprints. (iv) The applied load in surface interrogation is in fact regulated in response to the friction force. The limits in tactile perception were indirectly researched by similarity scaling experiments on the model surfaces. Wrinkle wavelengths of 760 nm and 870 nm could be discriminated from untextured reference surfaces, whereas 270 nm could not. The amplitude of the wrinkles so discriminated was approximately 10 nm, suggesting that nanotechnology may well have a role to play in haptics and tactile perception.
Taktil perception bidrar starkt till den sammantagna upplevelsen av en produkt, men hur materials olika ytegenskaper påverkar och styr perceptionen är ännu inte helt klart. Den här avhandlingen undersöker hur många och vilka egenskaper som är viktiga när känslan mellan två ytor jämförs. Tillvägagångssättet är tvärvetenskapligt där fysikaliska mätningar kopplas ihop med perceptions mätningar där människor används som instrument. Två typer av perceptionsförsök har utförts, multidimensionell skalning där försökspersoner sätter siffror på hur lika två ytor känns, samt magnitud estimation där i stället intensiteten på specifika perceptuella storheter som t.ex. upplevt lenhet, upplevd mjukhet och upplevd strävhet bedömdes. Eftersom taktil perception innebär kontakt samt relativ rörelse mellan hud och ytor, har fokus i avhandlingen varit att undersöka hur friktion och ytans struktur (ytråhet) påverkar och bidrar till den taktila perceptionen. Förutom fysikaliska mätningar på friktion och ytstruktur har värmekonduktivitet, mjukhet samt olika standard mätningar inom pappersindustrin mätts. En metod för att mäta friktion mellan ett finger och olika ytor har utvecklats för att i möjligaste mån återspegla friktionskomponenten i upplevt taktil perception. Friktionskoefficienter beräknades och jämfördes mellan alla ytor. De stimuli som har studerats är tryckpapper och mjukpapper samt modellytor, gjorda för att systematiskt undersöka hur ytstruktur påverkar perceptionen. Tillverkningsmetoden för modellytorna valdes så att ytorna var tåliga och kunde tvättas och därmed återanvändas. Strukturen på ytorna bestod av ett vågformat mönster där våglängden varierade mellan 270 nm och 100 µm och amplituden mellan 7 nm och 6 µm. Enligt vår vetskap är det första gången som strukturer i de här skalorna har gjorts utan att samtidigt ändra andra material egenskaper. Friktionskoefficienten minskade med ökad kvot mellan amplituden och våglängden på modellytorna samt med ytråheten på tryckpappren. En analytisk modell tillämpades på kontakten mellan ett finger och ytorna som visade att friktionskoefficienten beror av den verkliga kontaktarean. För de mycket grövre mjukpappren uppmättes inga stora skillnader i friktion förmodligen för att kontakarean mellan de olika mjukpapprena var lika. Den faktiska kontakarean visade sig också vara viktig för perceptionen av lenhet, strävhet, torrhet och svalhet. Det visade sig vara en stor perceptuell skillnad mellan olika typer av tryckpapper och mjukpapper utifrån hur stimuli placerade sig på en taktil karta. För de tre materialen användes enbart två alternativt tre egenskaper hos materialet för att särskilja mellan alla olika par. För tryckpapper verkade en viktig dimension kunna beskrivas av alla de perceptuella och fysikaliska egenskaper som har med kontaktarean att göra, d.v.s. lenhet, svalhet, torrhet, ytråhet, värmekonduktivitet samt friktion. För att taktilt särskilja mellan olika ytor där bara strukturen är varierade, kunde friktion och våglängden relateras till spridningen i kartan. Båda studierna stödjer duplex theory of texture perception, där ett spatialt sinne används för att särskilja en av de grövre ytorna från en slät, och ett vibrationssinne för att särskilja mellan olika släta strukturer. Friktionen visade sig alltså vara en viktig fysikalisk egenskap för strukturer under åtminstone 10 µm i ytråhet. Från fingerfriktions mätningar kunde även följande slutsatser dras: (i) Stora skillnader i friktionskoefficient mellan olika personer uppmättes, men trenderna mellan olika individer var samma, vilket gör att relativa skillnader i friktion från en individ är representativa. (ii) Lipider (fingerfett) som överförs från fingret till ytan vid kontakt sänker friktionen. (iii) Frekvensinnehållet i friktionskraften varierar mellan olika ytor och den frekvenstopp som ses vid 30 Hz kan möjligtvis bero på fingrets struktur eller resonansfrekvensen på huden. (iv) Den pålagda kraften under en friktionsmätning visar sig omedvetet regleras av den friktionskraft som fingret möter under rörelse. Hur små strukturer som kan diskrimineras har indirekt undersökts genom likhetsförsöket på modellytorna där försökspersoner skulle bedöma hur lika alla par av ytor kändes. Resultaten visade att ytorna med våglängder på 760 nm och 870 nm upplevdes olika jämfört med referens ytor utan något systematiskt mönster, medan ytan med 270 nm i våglängd inte kunde särskiljas. Amplituden på ytan som kunde diskrimineras var endast ca 10 nm, vilket indikerar att nanoteknologi mycket väl kan bidra inom haptiken och för att i framtiden kontrollera den taktila perceptionen.

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Simão, Miguel Martim Chambel. "Skin sensors for health care: paper-based flexible and wearable pressure sensor". Master's thesis, 2021. http://hdl.handle.net/10362/134280.

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The interest and need in portable, comfortable and durable health care sensors have increased along the years, due to their practicability and potential in helping people monitoring their vital signs. However, an all biodegradable low-cost sensor still poses a challenge to fabricate. So, cellulose is being used in the nanoscale form, due to filling all the necessary requirements with their excellent properties. The same can be said for metals like gold, silver and copper, which in the form of nanowires makes them great alternatives as sensing materials for pressure sensors. This work aims to develop a facile craft, low-cost, completely biodegradable, paper-based flexible and wearable pressure sensor for health care. The AgNWs are produced by the microwave-assisted polyol synthesis and purified with 3 decantation phases. The sensor substrate is made by pressing the bacterial nanocellulose (BNC) of nata de coco. The interdigitated electrodes (IDEs) are then screen-printed on its surface. The tissue paper is dip coated with the AgNWs, placed in the middle of the IDEs and encapsulated with the BNC, concluding the sensor construction. The sensor displayed a fast response time of 1.8 ms, a recovery time of 0.8 ms and it also showed high stability during 15000 cycles. The best sensitivity values achieved were 12.05 kPa-1 (0.031-1.4 kPa), 4.29 kPa-1 (1.4-2.8 kPa), 1.59 kPa-1 (2.8-5.6 kPa) and 0.38 kPa-1 (5.6-14 kPa), with the 6 dip coating cycles paper Tork on the sensor. The lowest detectable pressure was 31 Pa and the minimum and maximum energy consumption values recorded were 3.75×10-5 W and 1.32×10-2 W with a 2V working voltage.
O interesse e a necessidade em sensores de saúde portáteis, confortáveis e duráveis têm aumentado ao longo dos anos, devido à sua praticabilidade e potencial em ajudar as pessoas a monitorizarem os seus sinais vitais. No entanto, a produção de um sensor completamente biodegradável de baixo custo ainda representa um desafio. Por isso, vários tipos de celulose estão a ser usados à nanoescala por preencherem os requisitos necessários com as suas excelentes propriedades, assim como metais como o ouro, prata e cobre, que na forma de nanofios os torna ótimas alternativas como materiais de deteção em sensores de pressão. Este projeto tem como objetivo desenvolver um sensor de pressão fácil de fabricar, de baixo custo, completamente biodegradável, à base de papel, flexível e de fácil uso em cuidados de saúde. Os nanofios de prata são produzidos pela síntese poliol assistida por micro-ondas e purificados em 3 fases de decantação. O substrato do sensor é criado pressionando a nanocelulose bacteriana da nata de coco. Os elétrodos interdigitais são produzidos na sua superfície por impressão em tela. O papel é revestido com nanofios de prata por imersão, colocado no meio dos elétrodos interdigitais e encapsulado com a nanocellulose bacteriana, concluindo assim a construção do sensor. O sensor apresentou um rápido tempo de resposta de 1.8 ms, um tempo de recuperação de 0.8 ms e uma elevada estabilidade durante 15000 ciclos. Os melhores valores de sensibilidade obtidos foram 12.05 kPa-1 (0.031-1.4 kPa), 4.29 kPa-1 (1.4-2.8 kPa), 1.59 kPa-1 (2.8-5.6 kPa) e 0.38 kPa-1 (5.6-14 kPa) com o sensor a utilizar 6 ciclos de revestimento por imersão no papel Tork. O sensor também conseguiu detetar uma baixa pressão de 31 Pa e apresentou um consumo mínimo e máximo de energia de 3.75×10-5 W e 1.32×10-2 W, com uma tensão de trabalho de 2V.

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42

Cherebin, Oreoluwa. "Electrochemical tape-and-paper-based sensors suitable for oral pH measurements". Thesis, 2021. http://dx.doi.org/10.7912/C2/66.

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Indiana University-Purdue University Indianapolis (IUPUI)
Low oral pH (<5.5) has been shown to play an important role in dental erosion. The measurement of oral pH can be useful in preventative care, in aiding the dental caregiver in determining the likeliness of future dental cavities. The measurement of oral pH has become a popular area of research in an effort to develop a more quantitative method for the diagnosis of dental caries. We are developing an electrochemical tape-and-paper-based pH sensor for future applications in oral pH measurements. These tape-and-paper-based devices are low-cost, easy to fabricate, sterilizable, disposable and portable. The presence of intrinsic material defects of the painted graphite electrode generates oxo-groups which are electroactive. Some of these electroactive species, such as quinone, are pH-dependent and allow for the measurement of pH using cyclic voltammetry. There is shift in the potential of the redox peaks corresponding to the sensing species that can be correlated with the pH of a sample. We optimized the assay with a conditioning oxidative potential pre-treatment step and an ionic adjuster to carry out the pH measurements. We characterized the devices in different buffer solutions, as well as commercial pH standards and establish calibration curves. The reproducibility of the electrochemical response of the devices was also successfully across multiple devices and users. Their shelf-life was demonstrated to be at least three months. The devices successfully measured the pH of beverage and mouthwash, and different formulations of artificial saliva. Their performance in the presence bacteria and in growth media was assessed. Some complex matrices such as growth media required some additional optimization. Towards this objective we fabricated and tested devices with various formulations of carbon paste for the painted working electrode. These flexible tape-and-paper-based devices are promising sensors for pH measurements in oral samples and potentially even for in vivo and in situ pH measurements.

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43

Chuang, Tzu-Hsuan y 莊子萱. "Applications of polyaniline/cellulose nanofibrils composite at homemade paper-based sensors". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/7q29f9.

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碩士
國立交通大學
環境工程系所
107
Firstly, cellulose is extracted from rice straw by using different pretreatment factors. After that, Tetramethyl pyridine oxyl (TEMPO) oxidation method was implemented at room temperature to obtain the nanofibrillated cellulose. The hydrocarbon group on the cellulose surface are convert to carboxyl group. By electrostatically nucleating of the carboxyl group, We can overcome the hydrogen bond between the chain and the chain, and the cellulose nanofibrils is successfully obtained with a diameter of about 5 nm; Second, polyaniline are prepared with different concentrations of sulfuric acid and aniline. The conjugated structure makes it have good electrochemical properties after acid doping. However, at high concentration, the agglomeration of pure polyaniline hinders the movement of free radicals and reduces its electrochemical properties. Thus we try to prepare PANI/Cellulose nanofibrils. The fiber composite material provides an aniline adsorption template to avoid agglomeration. The conclusion is that when the cellulose nanofibrils is added, the redox current of the polyaniline/cellulose nanofibrils is 3 times of the original electrode. Third, we use polyaniline/cellulose nanofibrils for preparing paper-based sensor. The working electrode and auxiliary electrode are drawn by conductive carbon paste ,and the reference electrode is drawn by silver/silver chloride conductive paste. The hydrophobic barrier is drawn with a crayon. The thickness of the conductive carbon paste affects the electrochemical characteristics. When the number of printing times is increased to 6 times or more, the impedance tends to be gentle. The hydrophobic barrier is heated at 120 ° C for 5 minutes to avoid penetration of the wax liquid into the reaction zone. After the completion of the paper-based sensor, the polyaniline/cellulose nanofibrils were prepared under the same reaction conditions of the second part, and the sensitivity was tested with potassium ferricyanide system. Under optimum conditions, the Cu/PANI/ cellulose nanofibrils electrode exhibited a linear response range from 0.1 mM to 0.9 mM and low detection limit of 0.126 mM (n=7).

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44

CHEN, YAU-PING y 陳耀平. "Paper-based nano-composite electrodes and glucose sensors produced by inkjet printing". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/6d47rq.

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碩士
國立高雄應用科技大學
機械與精密工程研究所
104
The study aimed to apply inkjet printing (IJP) to generating the electrodes without the mask. Moreover, in this study, we established hydrophilic and hydrophobic regions on qualitative filter paper by polydimethylsiloxane (PDMS) to define the reaction area. An amperometric glucose biosensor with three electrodes was known to have excellent sensitivity and low detection limit featuring low cost, easy access, small volume, easy to operation, and convenient use. This sensing device was therefore fabricated with inkjet-printed nanosilver electrodes different from traditional screen-printed carbon electrodes (SPCEs). Using a fibrous filter paper and a material printer, the electrodes were printed directly in this work. The glucose biosensor allowed a small amount (1 μL) of sample solution for glucose analysis. The glucose biosensor had a linear calibration range of 1.66 to 7.77 mM glucose (R2=0.9914) with a sensitivity of 4.35 μA mM-1 cm-2. Finally, coating the structure of composite electrode with three-dimensional origami to produce glucose biosensors, the sensor can keep chemical solution without degeneration for a long time. Also it was measured with larger currents signal generated at a concentration of 2 to 5 mM range showing a high linearity (R2 = 0.9862) with a sensitivity of 68.19 μA mM-1 cm-2. This new paper-based electrochemical glucose biosensor was easy to operate and inexpensive. It can be used in the less developed countries for saving cost and time for the public.

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45

Matias, Maria Leonor Joaquim do Nascimento. "Paper-based nanoplatforms for multifunctional applications". Master's thesis, 2018. http://hdl.handle.net/10362/58117.

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In this work, zinc oxide (ZnO) and titanium dioxide (TiO2) nanostructures were grown on different cellulose paper substrates, namely Whatman, office, and commercial hospital papers, using a hydrothermal method assisted by microwave irradiation. Pure ZnO and TiO2 nanostructures were synthesized, however the growth of TiO2 above the ZnO was also investigated to produce a uniform heterostructure. Continuous ZnO nanorod arrays were grown on Whatman and hospital papers, however on office paper, it could be observed the formation of nanoplates originating nanoflower structures. TiO2 nanoparticles homogeneously covered all the substrates and, in some conditions, forming uniform TiO2 films. The structural characterization was carried out by SEM coupled with EDS, XRD and Raman spectroscopy. The optical characterization of all the materials was carried out. The produced materials were investigated for multifunctional applications, like photocatalyst agents, bacterial inactivators and ultraviolet (UV) sensors. To evaluate the photocatalytic activity under UV and solar radiations, rhodamine B was the model-test contaminant indicator and the best photocatalytic activity was achieved with Whatman paper. Hospital paper with TiO2 nanoparticles showed significant antibacterial properties against Staphylococcus aureus. ZnO-based UV sensors on Whatman demonstrated a responsivity of 0.61 μA W-1.

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46

Monteiro, Miguel Pedro da Conceição. "Flexible sensors technology for Point-Of-Care diagnostics with integrated micro fluidics on paper". Master's thesis, 2018. http://hdl.handle.net/10362/61574.

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Nowadays the hospitals and the medical centres face a huge challenge finding solutions to improve the efficiency of medical diagnosis. The scope of this project was to develop a “Point-of-Care Diagnostic” (POCD) device, that can give a better alternative for genetic analysis, instead of the usual methods of PCR (polymerase chain reaction). This device is composed by three layers. The first layer which works as a transporter and filter was built on paper. The second layer is the substitute of the regular thermocycling phase in the PCR technique and the third layer incorporates an interdigital capacitor that works as a DNA (deoxyribonucleic acid) sensor with high sensitivity to detect DNA hybridisation. These last two layers were made in kapton film. The devices were produced with microfabrication methods using inkjet printing, lithographic and deposition processes. The device’s characterisation was based on impedance spectroscopy methods. With the purpose of testing the device, the capacitor was functionalised with the YWHAZ gene. However, this process can be performed with any other gene. Due to its characteristics, the device under study was designed to run RT-qPCR (Real time quantitative polymerase chain reaction) and presents itself as an effective way to substitute the traditional PCR techniques. Even more, as the transport of samples to a laboratory and the recruitment of specialised personnel are not necessary, costs and response time are reduced.

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47

Tseng, Shih-Yu y 曾詩喻. "Paper-Based Sensors Prepared by Reversal Nanoimprint Technique in Food Safety and Heavy Metal Detection". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/hv7m4q.

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48

Chen, Chih Yao y 陳芝瑤. "A study on paper structure of sensory design". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/71813485086240564277.

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碩士
國立臺灣藝術大學
視覺傳達設計學系碩士班
101
In busy modern life, creative design is extremely important. Useful and creative design meets functional and sensory needs, in addition to easing pressure and making life better. Sensitive element in daily design adds fun to ordinary life. Shopping behavior is about "using" and "enjoy". Combining sensory demands, aesthetic and interaction between consumer and products, including vision, smell, sound, taste,is important for designers and corporations nowadays. Paper is simple, efficient, easy to produce for ordinary people. Paper is closely related to life. By experiment of combining paper techniques, paper become important in all aspects in everyday life. In order to take as references, the research categorize design cases of paper structure which uses sensitive element in everyday design. Theme: 紙享生活Paper in Life Human life in not only materials but spiritual needs. Designers develop human living quality by sharp sense to life. Works inspired by paper design give imagination to life with light, shadow and paper structure. With theme"Paper in Life", I developed series of "flower" and "afternoon tea", which shows different structure of one single element with various ways of aspects and display. The research creates atmosphere with sensory needs and study three element of sensory design: story, texture and fun, as inspiration of works. With paper texture and vision element, paper structure design make connection between consumer and product and introduce unique culture of paper to the world.

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49

Lin, Yu-Hsuan y 林侑萱. "A Study On The Paper Art Creations For Sensory Experience". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/07557966465109438218.

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碩士
國立臺灣藝術大學
視覺傳達設計學系碩士班
100
With the world-wide trend of shifting from service-based economy to experience-based economy, the “personal experience” has become an important criterion of modern industry’s expectations. By the articulating the human interaction with objects, services, and activities, it is possible to produce positive experiences that are profoundly beneficial to corporate image and the consumer as well. The prospect of active interaction and participation on client’s account necessitates the prominence of sensory experiences. With the advent of the information age and the dominance of its visual elements, a creative designer must call upon the virtues of alternative sensory experiences and use them to his or her advantage. Create unique designs that recall the forgotten senses from the dynamism of life. According to Martin Lindstrom’s 2005 study on sensory experience and consumer behavior, Lindstrom states that the sense of touch only ranks second to sight as one of the the decisive factors in subject’s purchase assessment. This means the articulation on the sense of touch is a viable and potent design approach, as the external texture and the quality of material play a crucial part in the beholder’s first impressions. This creative project has chosen paper as its primary medium due to its intimacy with virtually the entire sphere of human civilization. The works will be designed with a sensory-based approach, and be evaluated by the theories derived from research materials. This project aims to create works that (1).stimulate alternative senses apart from sight alone (2).relate to real-life scenarios. (3).offer the possibility of participation, and analyze the combination of the five senses in design. This will depend on the malleability of the material as the basis of creative process. Themes：Texture, image This project emphasizes on “texture-oriented creation” and “stimulation of five sensory experiences” as its two major focuses, expressing the vigor of life by the companionship with light. The project explores natural object and phenomenon that contains notion of time and uses them as inspirations, seven works have been created with this thought in mind, they are The Clouds, Rainbow, Pond, Moon, Trajectory of Wind, Bubbles, and Life. These works have been processed with a various techniques to express the malleability of paper, providing a different approach to observe and operate and become intimate to the beholder. Since the creation of these works, the following key points have been listed for future references and suggestions. 1. Design from a sensory-based approach: aims to deliver emotionally potent information and resonate with the beholder through design. 2. Articulate medium with aims to stimulate: (1).sensory stimulation (2).shape and texture stimulation. 3. Provide interaction through the processing of paper 4. Rethink and promote innovative paper craft design

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50

Chandini, Muniratnam Ammineni. "Design of lignin sensor for identification of waste paper grades for an automatic waste paper sorting system". 2001. http://www.lib.ncsu.edu/etd/public/etd-713187810152491/etd.pdf.

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Tesis sobre el tema "PAPER SENSORS"

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