Dissertations / Theses: 'Environmental sensors'

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Benton, Erin Nicole. "Development and Testing of Gold(I) and Europium(III) Based Sensors for Environmental Applications." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1505138/.

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This dissertation focuses on the development, characterization, and analysis of luminescent materials and coatings for sensing applications, including CO2, heavy metals, and silver. Chapter 2 involves the use of a gold(I) pyrazolate trimer that is able to detect silver ions with an AgNP medium. Detection of silver is vital, because there is an influx of silver into our environment caused by the increased use of AgNP. Therefore, having a sensor that is able to differentiate between and detect only Ag ions is an important first step to solving the toxicity mystery of AgNPs. Chapter 3 focuses on the development of sensor coatings containing a Eu(III) based luminescent system for sensing dissolved CO2 without the aid of an absorption-based dye. It is well-known that monitoring CO2 levels in our environment is important since even at low concentrations it can cause adverse health effects to the human body. This work demonstrates a pH-sensitive Eu complex being used directly as a CO2 sensor without the aid of any other absorption-based dye. Chapter 4 explores the idea of developing a heavy metal sensor for lead and its ability to detect lead in wide concentration range upon changing the pH of the medium and the polymer matrix. Different heavy metals have toxicity at different concentrations, therefore, being able to change the dynamic range of the sensor is advantageous. This research is the first step towards developing a luminescent Pb sensor with a tunable dynamic range.

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Arrigo, Leah M. "Phosphinimines as potential technetium environmental sensors." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4694.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 4, 2007) Vita. Includes bibliographical references.

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Chang, Seung Cheol. "Disposable amperometric sensors for environmental monitoring." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310134.

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Gong, Weidong. "Ocean sensors, for marine environmental monitoring." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/143801/.

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Various sensors and instruments were developed to measure the chemical and physical properties of sea water, but many are expensive and too large to be used on mass deployed vehicles such as the Argo float and submersed gliders. Marine mammal and fish tags require further sensor miniaturisation. This thesis describes the development of new in-situ micro sensor technology for marine environmental monitoring. Nitrite and nitrate are two forms of dissolved inorganic nitrogen in sea water and their availability is a key factor in the regulation of primary productivity in the sea. The in-situ determination of nitrite and nitrate in sea water presents a significant analytical challenge. In this thesis, a simple, low cost double beam spectrophotometer for use in a nitrite sensor for sea water analysis is presented. The sensor uses a colorimetric method to determinate nitrite concentration in sea water, based on Greiss reaction that forms as Azo dye whose absorbance is measured at a wave length of 540nm. The design incorporates a green LED and integrated photo-detectors to make the nitrite sensor compact, with low-cost and low-power consumption. A Conductivity, Temperature, Depth (CTD) sensor is the primary tool for determining the physical properties of sea water. A new CT (Conductivity and Temperature) micro sensor is presented in this thesis. The temperature sensor uses a thermistor, and the conductivity sensor uses a novel design of four planar electrodes built in an insulated channel. Conductivity sensors built of planar electrodes can be easily mass-produced on PCB boards, thus significantly reducing cost. This thesis includes the background of the measurement of conductivity, temperature and nitrite concentration in sea water. It also presents a comprehensive analysis of conductivity cells with two, four and five electrodes, together with the detailed multi-sensor interface design. The design and construction of the prototype sensors are described in detail, the key issues and test results are also presented.

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Pino, Flavio. "Development of nanomaterials for environmental monitoring." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/325142.

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El monitoreig ambiental basat en sistemes de biosensors té molta rellevància, no només en el camp de la investigació sinó també en aplicacions reals a nivell industrial. Això és degut als avantatges d’aquestes plataformes analítiques com, especialment, la seva simplicitat i alta rendibilitat pel seu cost. A més, els avenços recents en nanociència i nanotecnologia incrementen donen lloc a nous nanomaterials que tenen propietats elèctriques interessants com ara la seva capacitat de millorar la conductivitat dels elèctrodes. Aixó té un interès particular de cara al desenvolupament de sistemes de biosensors electroquímics. La combinació de nanomaterials amb biosensors electroquímics permeten construir eines d’anàlisi poderoses per al monitoreig mediambiental. Aquest és l’objectiu principal d’aquesta tesi, que descriu el desenvolupament i l’aplicació de tres nous biosensors pel monitoreig mediambiental mitjançant l’ús de nanomaterials. El primer capítol de la tesi proporciona una introducció general sobre el monitoreig mediambiental de contaminants i dona una breu descripció i classificació d’aquests components nocius. També dona una visió de la rellevància de l’ús de nanomaterials en sistemes de biosensors pel monitoreig mediambiental amb una detallada revisió dels últims treballs publicats que descriuen aspectes innovadors així com possibles inconvenients. Al capítol 3 es descriu una plataforma de monitoreig mediambiental basada en la inhibició de l’enzim acetilcolinesterasa. El sistema desenvolupat utilitza partícules magnètiques i l’enzim acetilcolinesterasa sobre elèctrodes de diamant dopats amb Bor. Gràcies a l’ús de partícules magnètiques i a les característiques de la superfície de l’elèctrode, aquesta plataforma és utilitzada com a sistema multi ús amb una alta reproducibilitat que és capaç de mesurar el pesticida chlorpyrifos en mostres reals d’aigua de riu (riu Yokoama, Japó). Al capítol 4 s’explica el desenvolupament de d’un sistema de detecció simultània de contaminants, el catecol (un derivat fenòlic) i el chlorpyrifos (un pesticida del grup dels organofosfats). Aquesta detecció s’aconsegueix utilitzant elèctrodes serigrafiats de carboni (screen printed carbon electrodes, SPCE) modificats amb nanopartícules d’òxid d’Iridi i amb tirosinasa. El biosensor proposat millora la sensibilitat en la detecció del catecol si es compara amb altres biosensors ja descrits en la bibliografia. Aquest biosensor mostra també una elevada sensibilitat en la detecció de chlorpyrifos quan s’utilitza el mode d’operació d’inhibició de la tirosinasa. Finalment, s’ha explorat l’eficiència del biosensor per aplicacions reals en aigua de riu i aigua de l’aixeta mostrant grans possibilitats per futures aplicacions com a plataforma de baix cost. El tercer biosensor desenvolupat s’explica al capítol 5. En aquest capítol es proposa un sistema de biosensors sense enzims basat en nanopartícules d’òxid de coure (CuO) per la detecció de components fenòlics i d’un herbicida altament tòxic, el Diuron. La detecció es fa mitjançant SPCE on les nanopartícules de CuO formen un complex estable amb els components fenòlics que es mesuren a partir de la reacció electroquímica que té lloc a la superfície de l’elèctrode. Val a dir que és una de les primeres aplicacions que s’utilitzen pel monitoreig mediambiental mitjançant l’ús de nanopartícules de CuO. Aquestes nanopartícules mimetitzen el centre actiu de la tirosinasa obtenint resultats comparables a altres plataformes enzimàtiques. Aquesta plataforma analítica pot ser utilitzada en aplicacions amb mostres reals donat que el límit de detecció obtingut es troba en els nivells que demana el monitoreig establerts per la legislació vigent.
Environmental monitoring based on biosensing systems has increased its relevance not only in the research field but also in the real industrial application. This is due to the advantages of such analytical platforms especially their simplicity and their cost/efficiency. Moreover, the recent advances in nanoscience and nanotechnology increase the emerging of new nanomaterials which have interesting electrical properties such as their capacity to improve the electrode conductivity. This has a particular interest in the development of electrochemical biosensing systems. The combination of nanomaterials with electrochemical biosensing platforms can build up powerful analytical tools for the environmental monitoring. This represents the main objective of this PhD Thesis, that divided in six chapters describes the development and application of three new biosensing platforms for environmental monitoring using nanomaterials. The first chapter of the thesis gives a general introduction on environmental monitoring of pollutants and offers a brief description and classification of these compounds. This chapter also gives an overview of the relevance of the use of nanomaterials in biosensing systems for environmental monitoring with a detailed review of the last published works describing also their innovation aspects and also the possible drawbacks. In Chapter 3 the biosensing platform for environmental monitoring based on the inhibition of acetylcholinesterase is described. The developed system uses magnetic beads and acetylcholinesterase enzyme over Boron Doped Diamond Electrode. Moreover, through the use of magnetic beads and the surface characteristics of the electrode, this platform is used as multi use system with high reproducibility able also to measure the pesticide chlorpyrifos in real sample (Yokoama river, Japan). In Chapter 4 a simultaneous detection system of pollutants for catechol (a phenol derivative) and chlorpyrifos (an organophosphate pesticide), is developed. Such sensing is achieved through a SPCE modified with IrOx NPs and tyrosinase. The proposed biosensor reports improvement in the sensitivity for catechol compared to previously reported biosensors. This biosensor shows also a high sensitivity for chlorpyrifos while being used in a tyrosinase inhibition mode operation. Finally the efficiency of this biosensor is explored for real applications in river and tap water showing great possibilities for future application as a low cost platform. In Chapter 5 a free enzymatic bio-sensing system based on CuO nanoparticles for detection of phenols compounds and for a high toxic herbicide (Diuron) is proposed. Such sensing is achieved through a SPCE where CuO NPs create a stable complex with phenolic compounds that are measured through electrochemical reaction at electrode surface. Moreover it is one of the first applications using CuO NPs for environmental monitoring. CuO NPs have the function to mimic the active centre of tyrosinase obtaining results comparable with other enzymatic platforms. This analytical platform can be used for real sample applications due to the fact that the detection limit is within the requested levels of monitoring established by the legislation. Annex A shows a very interesting review over the biosensing systems inenvironmental monitoring using nanomaterials. This review was published in a very high impact factor journal (Chemical Review Impact factor of 46.658).

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Schädle, Thomas [Verfasser]. "Mid-infrared sensors for environmental monitoring / Thomas Schädle." Ulm : Universität Ulm, 2017. http://d-nb.info/1124067841/34.

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Fang, Xinwei. "Improving data quality for low-cost environmental sensors." Thesis, University of York, 2018. http://etheses.whiterose.ac.uk/21259/.

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Using low-cost sensors to monitor the urban environment has become increasingly popular, as they can provide better data resolution than current practices. However, these low-cost sensors often produce poorer data quality, and so the data may not be utilised directly without processing. This thesis presents a two-phase solution for improving the data quality of low-cost environmental sensors. The solution consists of a novel method for anomaly detection and removal, and a process of sensor calibration. In the first phase, an anomaly model is utilised to identify the anomalies, which is constructed using a Bayesian-based approach. New contextual information is used to build the anomaly model, that is to the best of our knowledge the first time it has been used for such purpose. The result shows that this solution is more practical and robust than the existing approaches. In the second phase, a systematic comparison of the state-of-the-art calibration approaches is performed. The comparison aims to understand the difference between the methods, and the result shows a regression based method could provide a more predicable result and require much less computational resources. As a result, a regression based method is used for calibrating sensors in this work. In contrast to the existing approaches, the proposed method for calibration is able to systematically and automatically select the calibration parameters. The parameter selection ensures the best set of parameters are used in the model, which makes the calibration process less sensitive to different environmental conditions. The overall evaluations are performed using real datasets. The results show the data quality in terms of general accuracy against the reference instruments can be significantly improved, especially for sensors at roadside.

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Schädle, Thomas Fabian [Verfasser]. "Mid-infrared sensors for environmental monitoring / Thomas Schädle." Ulm : Universität Ulm, 2017. http://d-nb.info/1124067841/34.

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Pol, Arcas Roberto. "Printing technologies for biotechnological and environmental sensing applications." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/667857.

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Las actividades industriales han dejado contaminación en el suelo, el aire y el agua en todo el mundo. Las emisiones de SOx provenientes de gases de combustión requieren tratamiento antes de su liberación al medio ambiente. Los tratamientos fisicoquímicos convencionales utilizados hasta ahora son costosos y requieren mucho tiempo. Además, esos tratamientos también generan aguas residuales que requieren un procesamiento adicional. Para superar el desafío del tratamiento de SOx, se propone un nuevo enfoque que utiliza un método biológico respetuoso con el medio ambiente. El proceso se basa en una adsorción selectiva de SOx, seguida de un tratamiento biológico de dos etapas. Una vez adsorbidos los SOx, se someten a una primera etapa biocatalítica, en la que los microorganismos reductores de sulfato catalizan su conversión en sulfuro de hidrógeno. Posteriormente, se realiza una segunda etapa biocatalítica por microorganismos oxidantes de sulfuro, obteniendo finalmente azufre elemental. Un punto crucial que tratar en este proceso biotecnológico es la cuantificación en tiempo real de las especies de azufre antes y después de cada etapa biocatalítica. Los métodos convencionales, tales como la gravimetría, la turbidimetría, la nefelometría, la electroforesis capilar y la cromatografía iónica se han utilizado para la cuantificación de especies de azufre. Aunque esos métodos se han implementado de manera abrumadora hace unas décadas, no son adecuados para mediciones in situ y en tiempo real, requieren personal capacitado, son costosos y consumen mucho tiempo. Por lo tanto, existe la necesidad de proporcionar nuevos sistemas analíticos que puedan reemplazar a los convencionales. Las plataformas microfluídicas se han estudiado debido a su posibilidad de reemplazar un laboratorio convencional totalmente equipado. Las ventajas bien conocidas de estos sistemas de detección incluyen: compacidad, bajo consumo de muestra, producción de bajo coste, mejor monitoreo y control de procesos, análisis en tiempo real y una respuesta rápida. Estas características abren la posibilidad de realizar medidas in situ y en tiempo real. Además, funcionan de tal manera que el pretratamiento de la muestra y el ensayo químico se pueden realizar en su interior. Su diseño ergonómico y fácil de usar les permite adaptarse fácilmente para realizar el análisis deseado simplemente modificando la geometría de los canales. Estas características hacen que la microfluídica sea de interés en procesos que requieren múltiples análisis al mismo tiempo. Para la producción de sistemas analíticos miniaturizados se han utilizado varias técnicas de microfabricación (por ejemplo, micromaquinado, estampado en caliente, moldeo por inyección, ablación por láser, micromilling y litografía) y materiales (por ejemplo, silicio, polímeros, metales, cerámica, etc.). No obstante, todos estos métodos requieren personal capacitado, son costosos y requieren mucho tiempo. Además, requieren más pasos de procesamiento (por ejemplo, grabado químico, sellado, etc.) después de la fabricación. Hoy en día, los científicos han estado explorando nuevas metodologías para producir tales sistemas analíticos de una manera más factible y más barata. En esta tesis, se promueve el uso de tecnologías de impresión (impresión por chorro de tinta, serigrafía e impresión 3D) para producir plataformas analíticas para la cuantificación de compuestos químicos relevantes en reactores biotecnológicos y en el medio ambiente (S2-, SO42- and NO2-). Por lo tanto, el estado del arte de los dispositivos microfluídicos y los sistemas analíticos impresos se han desarrollado ampliamente:
Modern industrial activities have left wide-spread hazardous pollution in soil, air and water across the globe. Emissions of SOx coming from flue gases require treatment before their release into the environment. Conventional physic-chemical treatments used hitherto are expensive and time-consuming. Moreover, those treatments also generate wastewater that requires further processing. To overcome the SOx treatment challenge, a new approach using environmentally friendly biological method is proposed. The process is based on a selective adsorption of SOx, followed by a two-stage biological treatment. Once the SOx are adsorbed they undergo a first biocatalytic stage, in which sulfate-reducing microorganisms catalyze their conversion into hydrogen sulfide. Afterwards, a second biocatalytic stage by sulfide-oxidizing microorganisms is done, finally obtaining elemental sulfur. A crucial point to address in this biotechnological process is the real-time quantification of sulfur species before and after each biocatalytic stage. Conventional methods, such as gravimetry, turbidimetry, nephelometry, capillary electrophoresis and ionic chromatography have been widely used for sulfur species quantification. Although those methods have been overwhelmingly implemented a few decades ago, they are not suitable of in situ real-time measurements, require trained personnel and they are costly and time consuming. Therefore, there is a need to provide new analytical systems that can replace conventional ones. Microfluidic platforms have been extensively studied due to their possibility of replacing a fully equipped conventional laboratory. Well-known advantages of these microfluidic sensing systems include: compactness, low sample consumption, low-cost production, better overall monitoring and process control, real-time analysis and a fast response. These characteristics open the possibility of performing in situ and real-time measurements. Also, they operate in such a manner that sample pre-treatment as well as chemical assay can be performed therein. Their ergonomic and user-friendly design allows them to be easily adapted to perform a desired analysis just by simply modifying the geometry of the channels. These features make microfluidics of interest in processes that require multiple analyses at the same time. Several microfabrication techniques (e.g., micromachining, hot embossing, injection molding, laser ablation, micromilling and soft lithography) and materials (e.g., silicon, polymers, metals, ceramics, etc.) have been used for the production of miniaturized analytical systems. Nonetheless, all these methods require trained personnel and are expensive and time consuming. Moreover, they require further processing steps (e.g., etching, sealing, etc.) after the fabrication. Nowadays, scientists have been exploring new methodologies to produce such analytical systems in a more feasible and cheaper manner. In this thesis, the use of printing technologies (inkjet printing, screen-printing and 3D printing) to produce analytical platforms for quantification of relevant chemical compounds in biotechnological reactors and in the environment (S2-, SO42- and NO2-) are promoted. Hence, the state-of-the-art of microfluidic devices and the printed analytical systems have been widely developed.

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Chocarro, Ruiz Blanca. "Development of bimodal waveguide interferometric sensors for environmental monitoring." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/669867.

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La presente Tesis Doctoral está dedicada al desarrollo de novedosos sensores nanofotónicos como soluciones alternativas a las herramientas existentes de monitoreo medioambiental. En concreto, proponemos el uso de un novedoso sensor interferométrico, el dispositivo de guías de onda bimodales (BiMW), para el análisis selectivo, sensible, rápido y directo de contaminantes presentes en ambientes marinos y el aire. Para la detección de contaminantes en diferentes medios, agua y aire, se han seguido dos estrategias. La primera fue el desarrollo de un dispositivo biosensor basado en un inmunoensayo competitivo para la detección de bajas concentraciones de un pesticida directamente en agua de mar. Para lograr este objetivo, empezamos con un estudio en profundidad de diferentes estrategias de biofuncionalización porque la química de superficie debe optimizarse para maximizar la estabilidad, reproducibilidad y sensibilidad del inmunoensayo competitivo. Otro aspecto crucial para el desarrollo del biosensor fue la optimización de las condiciones del inmunoensayo. Nuestro inmunosensor final supera alguna de las técnicas analíticas actuales y ofrece una herramienta analítica avanzada para el control en tiempo real e in-situ de la contaminación del agua. La segunda estrategia propone la integración de redes metal- orgánicas porosas (MOFs) como receptores para desarrollar un sensor químico capaz de detectar pequeñas moléculas como los gases. Primero, se evaluó el tipo de MOF y se optimizó la integración en láminas delgadas. Luego, se evaluó el sensor MOF-BiMW de gases en términos de sensibilidad, selectividad, reproducibilidad y estabilidad. Los resultados demuestras que este nuevo sensor supera algunos de los inconvenientes de las metodologías actuales para la detección de gases. Este trabajo ha abierto el camino para una nueva línea de investigación basada en la implementación de herramientas avanzadas para el control medioambiental
This Doctoral Thesis is devoted to the development of novel nanophotonic sensors as alternative solutions for the existing environmental monitoring tools currently employed. In particular, we propose the use of a novel interferometric sensor, the bimodal waveguide interferometer device (BiMW), for the selective, sensitive, rapid and direct analysis of pollutants present in the marine and the air environments. For the detection of pollutants in different media, air and water, two strategies have been followed. The first approach was the development of a biosensor device based in a competitive immunoassay for the detection of traces of a pesticide directly in seawater. To achieve this objective, we started with an in-depth study of different biofunctionalization strategies because the surface chemistry needs to be optimized to maximize the stability, reproducibility and sensitivity of the competitive immunoassay. Another crucial step for the development of the pesticide biosensor was the optimization of the immunoassay conditions. Our final immunosensor overcomes some of the constraints of the current analytical techniques and offers an advanced analytical tool for the real-time and on-site monitoring of water pollution control. The second strategy proposes the integration of Metal-Organic Frameworks (MOFs) as receptors to develop a chemical sensor for the detection of small molecules such as gases. First, the type of MOF and the integration in thin films were evaluated and optimized. Then, the developed MOF-BiMW gas sensor was assessed in terms of sensitivity, selectivity, reproducibility and stability. Results show that this new sensor overcomes some of the drawbacks of the current methodologies for gas sensing. This work has opened the path of a new research line for the real implementation of advanced environmental monitoring sensing tools.

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Le, Goff Thierry. "Development of novel sensors for anions of environmental interest." Thesis, University of Plymouth, 2000. http://hdl.handle.net/10026.1/1134.

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A range of ion-selective electrodes (ISEs) for the determination of nitrate has been produced based upon rubbery membranes having covalently bound betaine salt sensor molecules. The best performing electrode contained N,N,N-triallyl leucine betaine (6.5 % m/m) covalently bound to polystyrene-block-polybutadiene-block-polystyrene (SBS) (43.5% m/m), with 2-nitrophenyIoctyl ether (2-NPOE) as solvent mediator (40 % m/m) and dicumyl peroxide (DCP) as free radical initiator (10% m/m). The Nemstian slope was -59.1 mV per decade over a linear range of 1 x 10'^-5 x 10"^ mol dm'^ nitrate, a limit of detection of 0.34 pmol dm'^ nitrate and a selectivity coefiBcient for nitrate against chloride ( ^ ° N 0 3 . , CI-) of 3.4 X IQ"^. The speed of response was less than 1 minute over the linear Nerastian range. The lifetime in the laboratory exceeded 5 months with no potentiometric drift over the linear Nemstian range. Temperafure dependency (0-25°C), pH range (2-12) and a selection of interfering anions (F', CI", B r , T, SCN, CIO4", HCO3", NO2", S04^ phthalate) were studied. A field evaluation by continuous immersion in both agricultural drainage weirs and a river were undertaken. The nitrate results obtained with the ISEs compared very favourably (R^=0.99) with those obtained with a segmented-flow instmment in a concentration range 0.47-16 ppm nitrate-N. The electrodes perfonned continuously for over 5 months in mnoff water from a field and over 2 months in river water. The ISEs did not require recalibration and no deterioration in performance or fouling of the membrane surface was observed. A preliminary investigation of a phosphate ionophore based upon a heterocyclic macrocycle was also undertaken. This work, based on previous literature, resulted in a dibasic phosphate electrode having a linear Nemstian range from 3 x lO"'' to 1 x 10"^ mol dm'^, a slope of -27 mV per activity decade and a Umit of detection of 1 x 10"^ mol dm"^ HP04^".

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Florea, Anca Stefana. "Electrochemical affinity sensors for biomedical, food and environmental applications." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10126/document.

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Les capteurs électrochimiques sont des outils pour la détection fiable, peu coûteux, avec une haute sensibilité et sélectivité, pour la détermination des composés biologiques et chimiques dans les domaines du diagnostic clinique, l'environnement et l'industrie alimentaire. Particulièrement, les Immunocapteurs, alliant une très grande spécificité. Également des nouveaux techniques produisent des résultats similaires, par exemple, les capteurs basés sur la technique des Polymères à empreinte moléculaire, la quelle produise des récepteurs artificiels. La technique devient très important dans les sciences bioanalytiques parce qu'il porte des avantages inhérents sur les récepteurs naturels: une grande stabilité dans des diffèrent environnement et conditions, également comptent avec une grande flexibilité dans la conception, une large gamme de molécules peuvent être utilisées. L'objectif du travail présenté ici est de développer des capteurs électrochimiques avec une très grande affinité et spécificité pour une analyte. Les quelles comprennent des applications très divers comme dans la protection de l'environnement, la sécurité alimentaire et le domaine biomédical. La première partie de la thèse présent l'état actuel de la conception et techniques de fabrication des biocapteurs. Ensuite, les aspects généraux des immuno capteurs électrochimiques et capteurs base sur des aptamères sont présentés ici, ainsi que plusieurs exemples rapportés dans la littérature pour la détection de marqueurs biologiques du cancer. Les avantages de l'intégration nanomatériaux dans les dispositifs de détection sont présentés. Ensuite, plusieurs aspects sur la technique des Polymères à empreinte moléculaire sont introduits. La partie personnelle de contribution est structuré en trois chapitres: en premier temps la méthodologie et les résultats obtenus pour le développement de deux essais biologiques pour la détection du marqueur tumoral Mucinl. Le premier chapitre est dédié sur un capteur à base de billes magnétiques, dans le deuxième chapitre une capteur aptamère base sur des nanoparticules d'or sans aucun marquage et finalement un capteur basée sur la technique des Polymères à empreinte moléculaire, cette protocole a été appliqué pour la détection d'explosifs, des médicaments, des hormones et les pesticides
Electrochemical sensors provide reliable and inexpensive tools for the determination of biological and chemical compounds with high sensitivity and selectivity, in the fields of clinical diagnosis, environment protection and food industry. Immunosensors hold particular promise, combining the high specificity of immuno- reactions with the sensitivity of electrochemical methods. Artificial receptors based on molecularly imprinted technique attracted considerable attention in bioanalytical sciences due to inherent advantages over natural receptors, such as high stability in harsh conditions and freedom of molecular design towards a wide range of molecules. The aim of the thesis presented here was to develop electrochemical affinity sensors based on various recognition receptors for environment monitoring, food safety and biomedical field. The first part of the thesis reviews the current state of knowledge in these fields. General aspects of electrochemical immuno- and apta-sensors are presented herein, together with several examples reported in the literature for the detection of cancer biomarkers. The advantages of integrating nanomaterials in sensing devices are then presented. At last, several aspects of the molecularly imprinted polymers are introduced. The personal contribution part is structured in three chapters, that include the methodology and results obtained for the development of biosensors for the detection of Mucinl tumor marker, the first chapter being focused on bioassays based on magnetic beads and second chapter on a label-free aptasensor based on gold nanoparticles, and finally, a third chapter dedicated to the molecularly imprinted-based sensors for the detection of explosives, drugs, hormones and pesticides

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Daher, Bassam William 1979. "Use of sensors in monitoring civil structures." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28629.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.
"September 2004."
Includes bibliographical references (p. 141-145).
This thesis surveys the use of sensors and sensor networks in monitoring civil structures, with particular emphasis on the monitoring of bridges and highways using fiber optic sensors. Following a brief review of the most widespread form of civil infrastructure inspection -- visual inspection -- the thesis describes the anatomy, mechanisms, and types of fiber optic sensors and characterizes the tradeoffs involved in choosing between fiber-optic and conventional sensor technologies. The thesis then presents a survey of contributions to this field, followed by a discussion of deployed applications of fiber-optic sensors, many of them in North America. The latter portion of the thesis first briefly discusses the emerging technology of wireless sensor networks and then presents an abbreviated case study comparing the costs and time required to deploy a fiber optic system to traditional visual inspection on the same structure. The case study suggests that the fiber optic sensors are a cost-effective technology, particularly when indirect savings are considered. The thesis concludes with some comments on the prospects and challenges for sensor technologies in civil infrastructure monitoring.
by Bassam William Daher.
S.M.

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Mascini, Marcello. "DNA and peptide based sensors for food and environmental applications." Thesis, Cranfield University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399122.

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Trustman, Benjamin D. "Characterizing Spatial and Temporal Variability of Snow Water Equivalent Using Pressure Sensors." Thesis, University of Nevada, Reno, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10126128.

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The goal of this study is to characterize spatial variability of snow water equivalent (SWE) at the meter scale. The study includes measurement of SWE with a new pressure sensor and use of meteorological sensor data to investigate physical properties within the snowpack that can affect sensor measurement. The new sensor, which can continuously measure a load equivalent to up to 5.5 meters of snow, is designed to be smaller and less expensive (< $1,500) than traditional pressure sensors (> $10,000). Manual snow cores and detailed snow pit analyses were performed to assess accuracy of the sensors and identify physical properties that may be related to sensor measurement error. SWE sensor response and accuracy were assessed between sensors and through comparison with bulk precipitation gage, manual SWE measurements, and snow pillows. SWE sensor readings compared favorably to other measurement methods, particularly in early and peak season. Spatial variability of SWE during the melt season of the two low-snow years during the study period confounded our ability to compare multiple sensor readings for validation. Spatial variability of SWE at study sites was calculated from sets of manual SWE measurements. The correlation length of 80 cm, determined using semi-variograms, highlights the small scale variability in SWE. Statistical resampling of manual measurements suggests that a minimum of ten manual measurements are needed to get within 10% of the spatial average of SWE. Although SWE can remain relatively stable during the melt period, this can be a result of increased density with decreasing snow depth, suggesting that simple inferences about SWE from depth measurements are not appropriate.

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Park, Jihyun. "Are Humans Good Sensors? Using Occupants as Sensors for Indoor Environmental Quality Assessment and for Developing Thresholds that Matter." Research Showcase @ CMU, 2015. http://repository.cmu.edu/dissertations/595.

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The indoor environmental quality (IEQ) of buildings can have a strong influence on occupants’ productivity and health. Post occupancy evaluation (POE) is the first step in assessing IEQ, and typically relies on subjective surveys of thermal quality, air quality, visual quality, and acoustic quality. However, the practice of conducting POE, from data collection during field studies to data coding, analyses and visualization, is very labor intensive. In addition, there is often a significant discrepancy between major IEQ standards and actual human perception. The Center for Building Performance and Diagnostics (CBPD) at Carnegie Mellon University (CMU) has expanded POE to include both objective IEQ measurements and records of the TABS that may affect indoor environment and user satisfaction. The suite of three tools including user satisfaction survey, technical attributes of building system and workstation IEQ measurements in the National Environmental Assessment Toolkit has been deployed in over 1600 workstations in 65 buildings, generating a rich database for statistical evaluation of the possible correlations between the physical attributes of workstations, measured environmental conditions, and user satisfaction. The database also supports a number of critical hypotheses relative to the complexity and depth of field data needed, the critical factors that must be collected, and the possibility that humans are indeed good sensors for many variables. The major statements that have been drawn from the research are as follows: (1) Because human health and performance outcomes are a result of an integration of indices, IEQ evaluation must include thermal, air, visual, and acoustic measures. (2) While POE with IEQ measurement is an ideal approach to assessing the full suite of environmental characteristics that impact human satisfaction, health and performance, field measurements are labor and cost intensive. (3) Building occupants can provide critical insights and even real measures of IEQ, and contribute to updating IEQ standards to reflect integrated realities. As such, this research revealed an integrated approach to POE +M by leveraging occupants as sensors to quickly capture IEQ conditions in a work environment. This approach can identify critical factors in the physical environment that impacts building occupant comfort and satisfaction. This approach provides practical IEQ assessment methods and procedures centered on the occupants’ perspective. The ultimate outcome of this research will contribute (1) correlations between occupant perception and measured data, (2) a refined survey method to assess building IEQ capable of robust prediction of building performance, and (3) metrics and guidelines for IEQ standards that capture new IEQ thresholds that impact building occupants’ comfort. The hypotheses tested in this thesis are summarized as follows: Hypothesis 1: Humans are effective sensors for POE+M. Combining occupant responses with key IEQ attributes can provide insight that is comparable to complex field instrumentation. Hypothesis 2: User satisfaction can inform design decisions. Comparing user satisfaction to instrumented IEQ measurements can inform acceptable thermal, air, visual, and acoustic design for occupant satisfaction. Hypothesis 3: Environmental thresholds are not adequate. Comparing user satisfaction to instrumented IEQ measurements can inform acceptable thermal, air, visual, and acoustic quality l conditions for occupant comfort. Multivariate regression, multiple correlation coefficient, and Pearson correlation statistical analysis of the database of 1600 workstations revealed the relationship between measured and perceived IEQ indices, interdependencies between IEQ indices and other satisfaction variables of significance. This research can contribute correlations between occupant perception and measured conditions, and metrics and guidelines for IEQ standards that capture new IEQ thresholds that impact building occupants’ comfort. The key findings of the IEQ data analysis are as follows: The result of the thermal quality revealed that smaller thermal zone, greater window quality, a level of control, measured air temperature at 60 cm from the floor, and radiant temperature asymmetry between exterior and interior walls are critical factors of temperature satisfaction. For air quality, operable windows, window quality, partition height, dedicated exhausts for printer and copy area, return air density are critical factors for overall air quality satisfaction. User satisfaction of the visual quality showed that seated view in the workstation is the most critical factor for user’s overall visual quality satisfaction. In addition, better ceiling fixture, ceiling lens type, window type and managing illuminance level on the work surface are important. Lastly, to ensure the acoustic quality satisfaction in both background noise and frequency from distraction from other people, bigger workstation, more partition sides, higher partitions and management of distributed noise source are critical for user comfort and perceived productivity. Overall, this thesis identified opportunities to improve the process of IEQ assessment by engaging occupants in POE, and define critical indicators for building occupant satisfaction. The results will contribute to the ongoing database of engaging humans as IEQ sensors. In the future, the findings and framework described here may be applied in different aspects of the building delivery process, such as building life cycle evaluation, building design, and the construction stage, to improve occupants’ thermal, air, visual, and acoustic conditions in the building.

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Tekle, Tesfalem Tsegay. "Ultrasonic stream bridge sensors (USBS) error in water level estimation." Thesis, University of Iowa, 2014. https://ir.uiowa.edu/etd/4770.

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After the flood event in 2008, Iowa Flood Center (IFC) designed a new water level measuring system, Ultrasonic Stream Bridge Sensors (USBS), to monitor stream water level in Iowa. The system is composed of an ultrasonic, a GSM cell modem, solar panel, and battery, and an internal temperature sensor; all components assembled in a weather proof box. The USBS are designed to be mounted in a bridge crossing and uses speed of sound to sense the distance from the sensor to the water surface. USBS are inexpensive compared to other system of water level measuring systems. However, ultrasonic sensor in USBS is very sensitive to variations in air temperature and changes in air density between the sensor and the water surface, which can be a major source of error in distance measurement. To reduce the effect of change in air density on the distance reading USBS internally compensates distance using temperature measured by its internal temperature sensor. IFC specifies that the sensor measures to an accuracy of 1% of the measurement range. However, more than three years of water level data collected by the sensors shows that there were fictional water level fluctuations to the order of +/- 7cm on average in most of the sensors. Spectral analysis done on the data also showed that the fluctuations have a strong diurnal cycle behavior. The cycle was stronger on South facing sensors. To reduce the error two methods of compensation were developed based on previous literatures and Senix Corporation advice. The first compensation method undoes the internal compensation and compensates the error using air temperature from nearby weather station. This method was applied to USBS who have close air temperature measurement from weather stations and to an experimental USBS installed in Iowa City airport. The method reduced the fluctuations by an average of 2cm in most of the sensor. The second method predicts local air temperature of the stream channel based on energy balance of the channel. The model predicted channel air temperature slightly less than air temperature from nearby weather station and we are able to reduce the fictional fluctuations on the order of 1cm.

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Kadara, Rashid. "Development of electrochemical sensors for heavy metal ions detection in environmental samples." Thesis, Cranfield University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398878.

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Milne, Rachel Mary. "Characterisation of Plasmodium and Trypanosoma brucei GPR89 homologues as candidate environmental sensors." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/20429.

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Plasmodium spp. and Trypanosoma brucei spp. are protozoan parasites with complex lifecycles, each having to adapt to the diverse environments of their insect vector and mammalian host. Each has multiple developmental forms that differ in their morphology and metabolism. Differentiation between these forms is a tightly regulated and often synchronised process in response to changes in the parasite's environment. The molecular mechanisms by which they perceive and respond to such environmental changes are largely unknown. The Plasmodium and T. brucei genomes encode a homologue of the phylogenetically widespread GPR89 family of putative receptors or channels. The mammalian GPR89 homologue has been implicated in the regulation of Golgo acidification, whilst in plants it has been shown to be involved in G protein signally pathways. This study set out to characterise the Plasmodium and T. brucei GPR89 proteins in order to assess their potential role as environmental sensors. Bioinformatic analyses demonstrated that the GPR89 proteins are a highly divergent family of multi-transmembrane domain proteins that may perform a channel or transporter function. Several expression strategies were employed to evaluate the role of the GPR89 proteins. Functional insight was gained from the ectopic expression of both the T. brucei and Arabidopsis thaliana GPR89 proteins in T. Brucei cells. Over-expression of TbGPR98 causes premature stumpy formation in pleomorphic T. brucei cells. This phenotype was replicated by over-expression of a A. thaliana homologue in T. brucei despite signigicatnt sequence divergence. Furthermore, both were demonstrated to act on the same pathway as the putatuve RNA binding protein, RBP7 that was receontly identified in a genome-wide screen for components of the stumpy differentiation pathway. Hence, TbGPR89 is likely a compnent of the slender to stumpy differentiation pathway in bloodstream form trypanosomes and there appears to be functional complementarity between T. brucei and A. thaliana GPR89 proteins.

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Suzuki, Takeharu, and n/a. "Integrated, Intelligent Sensor Fabrication Strategies for Environmental Monitoring." Griffith University. School of Microelectronic Engineering, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040813.131206.

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The humidity, temperature, wind speed/direction micro sensors can be manufactured individually, resulting in three individual substrates. The integration of the three sensors into a single substrate is a vital challenge to achieve an integrated intelligent sensor so called a multiple sensor. This requires the integration of process flows and is a major challenge because adequate sensor performance must be maintained. Polyimide was selected as a humidity sensing material for its compatibility with conventional integrated circuit fabrication technology, negligible temperature dependence and good resistance against contamination. Nickel was selected for the temperature and wind speed/direction sensor because of its useful temperature coefficient and the advantage of its cost. Since the known wet etchant for nickel requires hard-baked photoresist, a method which does not attack the polyimide while removing the photoresist must be developed. The method developed for etching nickel employs hard-bake-free photoresist. Other challenge was ensuring good thermal isolation for the wind speed/direction sensor fabricated on a silicon nitride layer preformed on top of a silicon wafer. Since silicon acts as a good heat sink, the silicon under the sensor was etched entirely away until the silicon nitride layer was reached. This structure achieved good thermal isolation resulting in small power consumption. This low power feature is essential for sensors deployed in fields where power access or replacement of power sources is restricted. This structure was compared with the structure created by polyimide plateau on a silicon nitride layer coated on a silicon substrate as a function of power consumption. Based on the examination of thermal isolation, the multiple sensor utilizing a MEMS technique was fabricated with a single-sided mask aligner. The characteristics of humidity sensors fabricated with polyimide were examined in detail with respect to variations of electrode structures, improvement of sensitivity, effect of process temperature, temperature and frequency dependence, and stability. The humidity sensor constructed with O2 plasma treated polyimide resulted an improvement in sensitivity and hysteresis. The investigation using XPS, FTIR and AFM concluded the chemical modification of polyimide played an important role in this improvement. The design, fabrication and results of a series of humidity sensors are quantified. There is always no unique packaging solution for sensors because of the application-specific nature of the sensors. This intelligent environmental monitoring system was designed to accommodate both an environmental sensor and its signal conditioning electronics circuitry (SICONEC) into a single package. The environmental sensors need direct exposure to the environment while SICONEC needs a sealed encapsulation to avoid environmental damage. A new style of packaging addressing these requirements was demonstrated using a hot embossing machine. The hot embossing machine was used to embed an integrated circuit (IC) in a bare die condition into a polycarbonate (PC) sheet. In this case, the IC was flipped down against the PC, which protects the front side of the IC from the environmental damages. In a test phase, a die containing operational amplifiers was embossed into the PC. A humidity sensor and surface mount resisters were placed on the same surface of the PC to test the validity of this new technique. Interconnection between the embossed die and the humidity sensor was established using bonding wires. Copper tracks were also used to ensure all electrical connections for the die, the humidity sensor and the resistors. The results clarified the method developed. Details of process methods, issues and further potential improvement are reported.

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Suzuki, Takeharu. "Integrated, Intelligent Sensor Fabrication Strategies for Environmental Monitoring." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367295.

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The humidity, temperature, wind speed/direction micro sensors can be manufactured individually, resulting in three individual substrates. The integration of the three sensors into a single substrate is a vital challenge to achieve an integrated intelligent sensor so called a multiple sensor. This requires the integration of process flows and is a major challenge because adequate sensor performance must be maintained. Polyimide was selected as a humidity sensing material for its compatibility with conventional integrated circuit fabrication technology, negligible temperature dependence and good resistance against contamination. Nickel was selected for the temperature and wind speed/direction sensor because of its useful temperature coefficient and the advantage of its cost. Since the known wet etchant for nickel requires hard-baked photoresist, a method which does not attack the polyimide while removing the photoresist must be developed. The method developed for etching nickel employs hard-bake-free photoresist. Other challenge was ensuring good thermal isolation for the wind speed/direction sensor fabricated on a silicon nitride layer preformed on top of a silicon wafer. Since silicon acts as a good heat sink, the silicon under the sensor was etched entirely away until the silicon nitride layer was reached. This structure achieved good thermal isolation resulting in small power consumption. This low power feature is essential for sensors deployed in fields where power access or replacement of power sources is restricted. This structure was compared with the structure created by polyimide plateau on a silicon nitride layer coated on a silicon substrate as a function of power consumption. Based on the examination of thermal isolation, the multiple sensor utilizing a MEMS technique was fabricated with a single-sided mask aligner. The characteristics of humidity sensors fabricated with polyimide were examined in detail with respect to variations of electrode structures, improvement of sensitivity, effect of process temperature, temperature and frequency dependence, and stability. The humidity sensor constructed with O2 plasma treated polyimide resulted an improvement in sensitivity and hysteresis. The investigation using XPS, FTIR and AFMconcluded the chemical modification of polyimide played an important role in this improvement. The design, fabrication and results of a series of humidity sensors are quantified. There is always no unique packaging solution for sensors because of the application-specific nature of the sensors. This intelligent environmental monitoring system was designed to accommodate both an environmental sensor and its signal conditioning electronics circuitry (SICONEC) into a single package. The environmental sensors need direct exposure to the environment while SICONEC needs a sealed encapsulation to avoid environmental damage. A new style of packaging addressing these requirements was demonstrated using a hot embossing machine. The hot embossing machine was used to embed an integrated circuit (IC) in a bare die condition into a polycarbonate (PC) sheet. In this case, the IC was flipped down against the PC, which protects the front side of the IC from the environmental damages. In a test phase, a die containing operational amplifiers was embossed into the PC. A humidity sensor and surface mount resisters were placed on the same surface of the PC to test the validity of this new technique. Interconnection between the embossed die and the humidity sensor was established using bonding wires. Copper tracks were also used to ensure all electrical connections for the die, the humidity sensor and the resistors. The results clarified the method developed. Details of process methods, issues and further potential improvement are reported.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Microelectronic Engineering
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Zhong, Guowei. "Rapid detection of trace metal ions on microfluidic platforms using gold nanoparticle sensors." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121545.

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The presence of metal ions, especially heavy metals, in various waters at elevated levels can pose a high risk to the environment and human health. Drinking water is one of the major sources that contributes to the daily intake of heavy metals by humans, and thus a rapid, low-cost and sensitive method for detection of heavy metal content in water is desirable. The goals of this study are to develop a chemical method for rapid testing of lead (PbII) ion in water solutions and to incorporate the method into a portable device for potential onsite applications. First, a rapid and sensitive colorimetric method for lead detection has been developed in this study by utilizing the unique optical properties and surface chemistry of gold nanoparticles (GNPs) and glutathione (GSH), which is a peptide used for lead recognition. In the reaction, GSH molecules serve as linkers to coordinate with both PbII and GNPs so as to aggregate the GNPs and thereby change the colour of the assay solution. The colour changes as measured by absorbance at selected wavelengths using UV-Vis spectrometry are proportional to the levels of PbII in aqueous samples, and thus quantification of PbII can be realized. As the reaction is based on label-free GNPs, no pre-modification is required. The limit of detection (LOD) of 6.0 ppb achieved by the method is lower than the maximum acceptable PbII concentrations (10 -15 ppb) in drinking water, indicating its high sensitivity and potential applicability in drinking water testing. The high selectivity for PbII against 10 metal ions has been demonstrated, and several masking agents were evaluated for their effectiveness in reducing potential inferences for an additional four metals. Second, a polydimethylsiloxane (PDMS) microfluidic chip was fabricated and coupled with a portable optical reader specifically designed for GNP probes. This device was first tested for detection of aluminum (AlIII) as a model compound by GNP probes to examine the compatibility of the microfluidic chip with the GNP probes and the sensitivity to the corresponding colour changes of the GNPs. It showed an LOD (1.2 ppm) comparable with that of UV-Vis Spectrometry (1.3 ppm) and operations were simple since only pipetting was required. The prominent feature of the device is that PDMS microfluidic chips are disposable and can be redesigned for other assays as well, such that the label-free GNP probes developed in this study for PbII detection can be possibly integrated in those microfluidic chips in the near future. The use of LED array light sources with controllable wavelengths is another feature to enable multi-analyte capability, which could be examined in the near future.
La présence d'ions métalliques en particulier les métaux lourds dans différents types d'eau à des niveaux élevés peut présenter un risque important pour l'environnement et la santé humaine. L'eau potable est l'une des principales sources qui contribuent à l'apport quotidien en métaux lourds chez l'humain, et donc une méthode rapide, peu coûteuse et sensible à la détection des métaux lourds dans l'eau est en grande demande. Les objectifs de cette étude est de développer une méthode chimique pour un dépistage rapide d'ion de plomb (PbII) en phase aqueuse et d'intégrer la méthode dans un dispositif portable à des fins d'applications potentielles sur place. Premièrement, une méthode colorimétrique rapide et sensible à la détection de plomb a été développée dans cette étude en utilisant les propriétés optiques uniques et la chimie de surface des nanoparticules d'or (GNPs) et le glutathion (GSH), qui est un peptide utilisé pour la reconnaissance de plomb. En réaction, les molécules de GSH servent de relieurs à fin de coordonner avec le PbII ainsi que le GNPs de manière à regrouper les sondes GNPs et ainsi changer la couleur du dosage. Les changements de couleur mesurée par absorption à des longueurs d'onde sélectionnées en utilisant la spectrométrie d'UV-Vis sont proportionnels au niveau du PbII dans des échantillons aqueux, permettant ainsi la quantification de PbII. Comme la réaction est basée sur l'utilisation des GNPs non-libellés, pas de pré-modification est requise. La limite de détection (LOD) de 6,0 ppb réalisée par la méthode est inférieure aux concentrations maximales de PbII acceptable (10 à 15 ppb) dans l'eau potable, ce qui indique sa haute sensibilité et applicabilité potentielle en analyse d'eau potable. Une haute sélectivité pour le PbII contre 10 ions métalliques a été démontrée, et plusieurs agents masquant ont été évalués pour leur efficacité dans la réduction des interférences potentielles pour quatre autres métaux. Deuxièmement, une puce microfluidique en polydiméthylsiloxane (PDMS) a été fabriqué et couplé à un lecteur optique portable spécialement conçu pour les sondes de GNPs. Cet appareil a été d'abord testé pour la détection de l'aluminium (AlIII) comme composé modèle, par des sondes de GNPs à fin d'examiner la compatibilité de la puce microfluidique avec les sondes de GNPs et la sensibilité aux changements de couleur correspondante du GNPs. Elle a démontré une LOD comparable (1,2 ppm) à celui de la spectrométrie UV-Vis (1,3 ppm) et les opérations étaient simples puisque seulement le pipetage était nécessaire. L'aspect remarquable du dispositif est que les puces microfluidiques de PDMS sont jetables et peuvent être reformulées pour d'autres dosages ainsi, de sorte que les sondes de GNPs non-libellées développées dans cette étude pour la détection de PbII peuvent être éventuellement intégrés dans des études futures. L'utilisation des sources de lumière à faisceau LED aux longueurs d'onde contrôlables est une autre caractéristique permettant une capacité multi-analyte, qui pourrait être examinée dans un proche avenir.

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Mathanlal, Thasshwin. "Design and Development of Perpetual Environmental Station (PES1)." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-64612.

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The Perpetual Environmental Station (PES1), designed and developed is robust, modularenvironmental station with a multitude of sensors, to study the precursors of Earthquakes and todisseminate a long term, quality data of various atmospheric parameters. The PES1 has beendesigned based on the Earthquake precursors, postulated in various research articles. Most ofthese postulated precursors have been tested in laboratory environments and PES1 will be thefirst station to validate these precursors on field. The PES1 has been designed from a modularpoint of view, considering perpetuity where modules can be easily added, replaced, or upgradedsuch that a long-term functioning of the system is guaranteed. The PES1 will be installed inIceland where the seismic activity is quite high, serving as an ideal test location.The thesis work outlines the precursors of Earthquakes and the seismicity in Iceland, where thePES1 is to be installed. The design and development of the PES1 is described from the hardwareand software point of view, with specifications of each sensor used in the Environmental Station.

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Darmawangsa, Darmadi. "Optical fiber sensors embedded in concrete structures : feasibility and durability studies." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/40154.

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Thesis (Civ. E.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1996.
Includes bibliographical references (leaves 292-295).
by Darmadi Darmawangsa.
Civ.E.

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Vickery, Kathryn J. "Southern African dust sources as identified by multiple space borne sensors." Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/4814.

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Includes abstract.
Includes bibliographical references (leaves 132-145).
Mineral aerosols emitted from arid and semi-arid regions effect global radiation, contribute to regional nutrient dynamics and impact local soil and water quality. Satellite imagery has been central to the identification and determining the distribution of source areas and the trajectories of dust around the globe. This study focuses on the dryland regions of Botswana, Namibia and South Africa. It uses the capabilities of the ultraviolet channels provided by the older Total Ozone Mapping Spectrometer (TOMS), the Ozone Monitoring Instrument (OMI) (a TOMS follow up), the visible bands of Moderate Resolution Imaging Spectroradiometer (MODIS), and the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard Meteosat Second Generation (MSG). This study compares various dust detection products but also focuses on the application of thermal infrared bands from MSG through the usage of the new "Pink Dust" visua lisation technique using channels 7 (8.7 ~m), 9 (lO.8 ~m), and 10 (12.0 ~m). This multisensor approach resulted in a regional maps highlighting the distribution of source points and establishing some of the prevalent transport pathways and likely deposition zones. Southern African dust sources include a few large and many small pans, subtle inland depressions and ephemeral river systems, which are subject to a range of climatic conditions as part of the Kalahari and Namib region. This work in particular examines if source points are productive due to favourable climatic conditions. The debate around transport limit verses supply limit can only be solved at the local scale which requires observation at higher spatial and temporal resolution as provided by the latest dust detection products. MSG and MODIS in particular have shown distinct source point clusters in Etosha and the Makgadikgadi Pans which based on the courser resolution of older TOMS, have so far been treated as homogeneous sources. Data analyses reveal 327 individual dust plumes over the 2005-2008 study period, some of which are more than 300 km in length. These are integrated into existing climate and weather records provided by National Centers for Environmental Prediction (NCEP) data. The results identified a set dust drivers such as the Continental High Pressure, Bergwinds, Tropical Temperate and West Coast Troughs, and Westerly and Easterly Wave lows. This enhances our ability to predict such events, in particular, if transport acts as the limiting driver. Some of these find ings also have the potential to enhance our knowledge of the aerosol generation process elsewhere. The quality of findings are still limited by problems associated with dust plume substrates and clearly require significant surface validation relating to hydrological and climatic controls at the micro-scale. It is furthermore evident that no current instrument fully meets the requirements of the mineral aerosol research community.

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Torres, Isis L. Fernandez. "Soil environment monitoring using sensors to predict microbial organic waste assimilation." Diss., Connect to online resource - MSU authorized users, 2008.

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Thesis (M.S.)--Michigan State University. Dept. of Biosystems and Agricultural Engineering, 2008.
Title from PDF t.p. (viewed on Aug. 10, 2009) Includes bibliographical references (p. 90-92). Also issued in print.

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Bhattacharyya, Rahul. "Low-Cost, Passive UHF RFID Tag Antenna-Based Sensors for Pervasive Sensing Applications." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/73791.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 161-170).
In the future, large-scale sensor deployment would enable many areas such as infrastructure condition monitoring and supply chain management. However, many of today's wireless sensor technologies are still too expensive to meet this need. Radio Frequency IDentification (RFID) offers good potential for the development of pervasive sensors: RFID tags have a proven track record of large-scale, highly integrated deployment for object identification in the retail and consumer goods industry. Furthermore, the last decade has seen much progress in making RFID a reliable, standardized wireless communication medium with the ability to mass produce low-cost RFID tags. My thesis introduces the concept of RFID Tag Antenna-Based Sensing (RFID TABS). In this approach, a change in the sensed parameter of interest induces a controlled change in the geometry or boundary conditions of an RFID tag's antenna. The resultant change in the tag's response signal can then be detected by an RFID reader. My approach builds upon current developments in RFID technology. For instance, the manufacturing techniques for the mass production of low-cost RFID tags can be used for pervasive tag-sensor development. My thesis examines TABS in a two-pronged approach: First, I demonstrate how three fundamental tag and reader signal properties can be used for sensing and propose three classes of TABS: -- Amplitude Modifying (AM) TABS use RFID reader transmitted power and tag response power for sensing. I illustrate proof of concept using a displacement sensor. I demonstrate that both these power metrics can be used to reliably measure structural displacement to a precision of 2.5 mm using commercial RFID tags. -- Frequency Modifying (FM) TABS relate changes in the sensed parameter to a shift in the tag's optimal operating frequency - the carrier frequency for which the tag is best tuned to respond to the reader. I demonstrate proof of concept using a temperature threshold sensor - the crossing of a design temperature threshold results in a shift in the sensor's optimal operating frequency. I demonstrate that the sensor works reliably over a 3 m read range and in different environmental conditions. -- Phase Modifying (PM) TABS use tag backscatter phase for sensing. I provide a brief summary of the factors influencing RF phase and outline the design for a PM TABS fluid level sensor that uses RFID tag response phase to detect the presence or absence of fluid in a beverage glass. I highlight the challenges in the practical implementation of this approach by demonstrating the sensitivity of RFID tag phase to three extraneous factors. Second, I introduce the concept of Non-Electric Memory to record short timescale threshold crossovers in the sensed parameter that may occur when the tag-sensor is unpowered. When information about, rather than the exact time of, the threshold occurrence is sufficient, non-electric memory provides a solution. I demonstrate how non-electric memory can be integrated into sensor design at minimal added cost. In the proof of concept of a temperature threshold sensor, I design a thermally actuated shape memory polymer switch to permanently change the electrical properties of an RFID tag when the temperature threshold is crossed. I demonstrate that the design works reliably over a read range of 3 m and is independent of the material on which the sensor is deployed. In summary, this thesis demonstrates how an RFID tag can be adapted for low cost, pervasive sensing. Sensor prototypes illustrate proof of concept in three application areas. Extensions to two other applications are also discussed.
by Rahul Bhattacharyya.
Ph.D.

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Pokhrel, Lok R., Nicholas Ettore, Zachary L. Jacobs, Asha Zarr, Mark H. Weir, Phillip R. Scheuerman, Sushil R. Kanel, and Brajesh Dubey. "Novel Carbon Nanotube (cnt)-Based Ultrasensitive Sensors for Trace Mercury(ii) Detection in Water: A Review." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/2878.

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Infamous for “Mad hatter syndrome” and “Minamata disease”, mercury (Hg) is ranked high on the Agency for Toxic Substances and Disease Registry's priority list of hazardous substances for its potent neurologic, renal, and developmental toxicities. Most typical exposures are via contaminated water and food. Although regulations and advisories are exercised at various levels, Hg pollution from both natural and anthropogenic sources has remained a major public health and safety concern. Rapid detection of solvated aqueous Hg2+ ions at low levels is critical for immediate response and protection of those who are vulnerable (young children, pregnant and breast-feeding women) to acute and chronic exposures to Hg2+. Various types of sensors capable of detecting Hg in water have been developed. In particular, the novel use of engineered carbon nanotubes (CNTs) has garnered attention due to their specificity and sensitivity towards Hg2+ detection in solution. In this focused review, we describe the sensitivity, selectivity and mechanisms of Hg2+ ion sensing at trace levels by employing CNT-based various sensor designs, and appraise the open literature on the currently applied and “proof-of-concept” methods. Five different types of CNT-based sensor systems are described: potentiometric, DNA-based fluorescence, surface plasmon resonance (SPR), colorimetric, and stripping voltammetric assays. In addition, the recognized merits and shortcomings for each type of electrochemical sensors are discussed. The knowledge from this succinct review shall guide the development of the next generation CNT-based biochemical sensors for rapid Hg2+ detection in the environment, which is a significant first step towards human health risk analysis of this legacy toxicant.

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Salustiano, Rogerio Esteves 1978. "Aplicação de tecnicas de fusão de sensores no monitoramento de ambientes." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/262032.

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Orientador: Carlos Alberto dos Reis Filho
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
Made available in DSpace on 2018-08-05T17:36:56Z (GMT). No. of bitstreams: 1 Salustiano_RogerioEsteves_M.pdf: 3698724 bytes, checksum: a5c6d59ec19db38f5a0324243ddb1eb5 (MD5) Previous issue date: 2006
Resumo: Este trabalho propõe um sistema computacional no qual são aplicadas técnicas de Fusão de Sensores no monitoramento de ambientes. O sistema proposto permite a utilização e incorporação de diversos tipos de dados, incluindo imagens, sons e números em diferentes bases. Dentre os diversos algoritmos pertinentes a um sistema como este, foram implementados os de Sensores em Consenso que visam a combinação de dados de uma mesma natureza. O sistema proposto é suficientemente flexível, permitindo a inclusão de novos tipos de dados e os correspondentes algoritmos que os processem. Todo o processo de recebimento dos dados produzidos pelos sensores, configuração e visualização dos resultados é realizado através da Internet
Abstract: This work proposes a computer system in which Sensor Fusion techniques are applied to monitoring the environment. The proposed system allows the use and incorporation of different data types, including images, sounds and numbers in different bases. Among the existing algorithms that pertain to a system like this, those, which aim to combine data of the same nature, called Consensus Sensors, have been particularly implemented. The proposed system is flexible enough and allows the inclusion of new data types and their corresponding algorithms. The whole process of receiving the data produced by the sensors, configuration of produced results as well as their visualization is performed through the Internet
Mestrado
Eletrônica, Microeletrônica e Optoeletrônica
Mestre em Engenharia Elétrica

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Klug, Katherine E., and Katherine E. Klug. "Novel Portable Sensors and Techniques for Improving On-Site Water Quality and Environmental Monitoring." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/626354.

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Recent research advances have improved techniques and devices, both standalone and smartphone-integrated, in the hope of achieving traditional analytical instrument-grade quality in a portable format, but the broad applicability of this work in many resource-limited settings is still a challenge due to inherent limitations in platform sensitivity, environmental interference, and assay versatility. This dissertation encompasses a series of four research projects designed for answering the challenges of portable environmental monitoring for resource-limited settings. First, we investigated control measures for existing portable environmental sensing techniques for heavy metal, organic molecular, inorganic compound, and biological targets. Initially, we characterized assay performance across diverse intensity-based detection methods and under diverse lighting and imaging conditions. Subsequently, we implemented lighting and imaging control measures and compared assay performance under each set of conditions. Following these analyses, we investigated the applications of three novel sensing methods. The second project encompasses our investigations of a transducer mechanism relating pathogen concentration to capillary flow rate based on differing interfacial/rheological-properties of target and antibody-conjugated particle samples. Capillary flow models were constructed and validated with these assay results to characterize the underlying operational mechanisms. The third project details a novel fluorescence-based assay for identifying and quantifying bisphenol A, an emerging environmental contaminant and endocrine disrupting compound, from treated effluent sample models. Additionally, this method was demonstrated on two smartphone platforms for device performance comparison. The fourth and final project covers particle-scattering based detection of heavy metal ions based on differing adsorption to carboxyl groups on different size particles detection at different angles. This work included the development of multivariate classification models by statistical inference methods, which allowed distinction between some heavy metal ion species. These four projects offer but a few directions which may prove valuable toward developing versatile sensing methods for resource-limited settings.

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Walker, David. "Biofouling and its control for in situ lab-on-a-chip marine environmental sensors." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/354418/.

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Biofouling is the process by which biological organisms attach to surfaces in an aqueous environment. This occurs on nearly all surfaces in all natural aquatic environments, and can cause problems with the functioning of scientific equipment exposed to the marine environment for extended periods. At the National Oceanographic Centre in Southampton (NOCS), the Centre for Marine Microsystems (CMM) is developing lab-on-chip micro-sensors to monitor the chemical and biological environment in situ in the oceans. Due to the long periods (up to several months) that these sensors will be deployed, biofouling by microbial biofilms is an important concern for the efficient running of these sensors. The aim of this project was therefore to determine the potential level of fouling within the sensors and to investigate the potential use of low-concentration diffusible molecules (LCDMs) to remediate biofouling. Many of the sensors in development by CMM are designed to sense specific chemical species and they use various chemical reagents to achieve this. The effects of some of these reagents on the formation of biofilms by mixed marine communities were investigated. It was shown that Griess reagent and ortho-phthadialdehyde (OPA), used to sense nitrites and ammonium respectively, effectively stop biofilm formation by killing microorganisms before they can attach to surfaces. Biofouling on two different polymers, cyclic olefin copolymer (COC) and poly (methyl methacrylate) (PMMA), used in the construction of micro-sensors, was compared with biofouling on glass. No differences were observed between COC and PMMA, however a small but significant difference in surface coverage was observed between glass and COC at the early stages of exposure to the marine environment. The lack of differences between the two polymers suggests that biofouling is not an important consideration when deciding whether to construct sensors from COC or PMMA. However, the larger degree of fouling on hydrophobic COC compared with hydrophilic glass indicates a potential use of surface modifications as an antifouling strategy. The effects on biofouling of the LCDMs nitric oxide (NO), cis-2-decenoic acid (CDA) and patulin, were investigated to evaluate their potential for anti-fouling in marine micro sensors. All three molecules were shown to reduce the formation of biofilms by mixed marine communities, but colony counts suggested that the effect of patulin was due to toxicity as opposed to a physiological effect. Investigation of biofilm growth in the light and the dark revealed that there was less biofilm formation in the light that the dark and this effect was determined to be due to an interaction with the polystyrene growth substratum. Analysis of the biofilm communities grown in the presence of LCDMs by denaturing gradient gel electrophoresis (DGGE), showed no clear differences in community profiles depending on the LCDMs. However those biofilms grown in the light appeared to have a greater proportion of Alphaproteobacteria than those grown in the dark. Further study is needed to determine the level of fouling and the applicability of LCDMs in real micro-sensor systems. However, this study has shown that LCDMs have the potential to remediate, at least in part, the biofouling of marine micro-sensors.

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Nasir, Tauqir. "Electrochemical sensors of environmental pollutants based on carbon electrodes modified by ordered mesoporous silica." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0089/document.

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Dans cette thèse, nous présentons la détection électrochimique des herbicides, c'est-à-dire le paraquat et l'isoproturon dans des échantillons aqueux. Leur utilisation intensive est une source de contamination de l'environnement et leur toxicité constitue une menace pour la santé. La détection électrochimique est une technique prometteuse et avantageuse par rapport aux méthodes de détection conventionnelles en raison de ses propriétés telles que l'analyse rapide, la facilité d'utilisation, la rentabilité et la sensibilité élevée résultant de la modification de l'électrode de travail. Ici, nous avons modifié les électrodes modifiées avec des films minces de silice mésoporeuse pour agir comme capteurs d'herbicide. Ces électrodes ont été modifiées par un processus d'auto-assemblage assisté par électrochimie, un processus bien établi pour la modification des électrodes par notre groupe. Dans la première partie, l'adhérence du film de silice mésoporeux aux électrodes de carbone a été améliorée à l'aide d'une amine primaire qui a agi comme colle moléculaire pour une meilleure fixation de ces films à la surface des électrodes. Dans la partie suivante, ces électrodes modifiées ont été utilisées pour la détection électrochimique des herbicides susmentionnés. Les électrodes modifiées ont montré une sensibilité accrue et une limite de détection basse par rapport aux électrodes non modifiées. L'effet des différents paramètres de la solution ainsi que l'épaisseur du film et la géométrie de l'électrode ont également été étudiés et ont un impact critique sur la sensibilité du système
In this thesis, we present the electrochemical detection of herbicides i.e. paraquat and isoproturon in aqueous samples. These herbicides are used worldwide extensively for weed control in different crops. Their intensive use is a source of environmental contamination and their toxicity is a threat to Human health. Electrochemical sensing is a promising and advantageous technique as compared to conventional detection methods due to its properties such as rapid analysis, ease of operation, cost effectiveness and high sensitivity as a result of working electrode modification. Here, we modified electrodes modified with mesoporous silica thin films to act as herbicide sensors. These electrodes were modified by electrochemically assisted self-assembly process, a well-established process for electrode modification by our group. In the first part adhesion of mesoporous silica film at carbon electrodes was improved with the help of a primary amine which acted as molecular glue for better attachment of these films at electrodes surface. In the next part these modified electrodes were used for electrochemical detection of above stated herbicides. Modified electrodes showed enhanced sensitivity and low limit of detection as compared to unmodified ones. Effect of different solution parameters as well as film thickness and electrode geometry was also studied and found to have critical impact on sensitivity of the system

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Elvin, Niell Glen. "Damage detection in civil and aerospace structures with fiber optic sensors." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/37018.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1995, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1995.
Includes bibliographical references.
by Niell Glen Elvin.
M.S.

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Zervaki, Orthodoxia. "Calibration and Evaluation of Low-Cost Optical Dust Sensors and Monitors." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535634263839935.

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Sherchan, Samendra Prasad. "Monitoring Microbial Water Quality via Online Sensors." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/293470.

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To protect public health, detection and treatment technologies have been improved to monitor and inactivate pathogens in drinking water. The goal of this dissertation is to evaluate and utilize multiple online sensors and advanced oxidation processes to document both the detection as well as destruction of microbial contaminants in real-time. Reviews of rapid detection technologies for real-time monitoring of pathogens in drinking water and advanced technologies to inactivate pathogens in water are shown in Appendices A and B. The study in Appendix C evaluated the efficacy of real-time sensors for the detection of microbial contaminants. Bacillus thuringiensis was used in this research as a surrogate for Bacillus anthracis to determine each sensor response and detection capability. The minimum threshold responses of sensors were determined by injecting B.thuringiensis into deionized (DI), raw (unfiltered) tap water, or filtered tap water over a concentration range of 10² - 10⁵ spores/ml. The BioSentry sensor responded to increases in concentration over the range of 10² - 10⁵ spores/ml. Below this range, sensors provided signals undistinguishable from background noise. The select sensors can detect microbial water quality changes, and these advanced technologies can be integrated to monitor intrusion events in water distribution systems. The study in Appendix D evaluated the efficiency of the UV reactor for inactivation of MS2 coliphage. The virus MS2 coliphage (ATCC 15597-B1) has been proposed by the U.S. Environmental Protection Agency as a standard for UV reactor validation in the United States. In addition, MS2 is used as a surrogate for enteric viruses due to its similar size and morphology. Following UV radiation at a flow rate of 2gpm, infective MS2 showed a reduction of 5.3- log₁₀ when quantified with cultural plaque counts, whereas corresponding quantitative polymerase chain reaction (qPCR) data showed only a 1.7- log₁₀ reduction in viral RNA copy number. In contrast, plaque assay revealed a 5.8- log₁₀ inactivation; a slight increase in infective MS2 coliphage reduction at 1 gal per min but qPCR results indicate a 2.8- log₁₀ reduction in viral RNA copy number; a one log more inactivation compared to 2 gpm. When H₂O₂ was added at either 2.5 or 5 mg/l with UV at either flow rate, enhanced MS2 inactivation occurred with a greater than 7 log₁₀ reduction observed via plaque counts, indicating that all added MS2 had been inactivated, since no plaques were formed after incubation at 37°C for 24 hours. Correspondingly, qPCR data only showed a 3-4 log₁₀ reduction in viral RNA copy number. The study in Appendix E utilized online sensor to document the destruction of E.coli and Bacillus thuringiensis spores by UV/H₂O₂ treatment. In this study, Escherichia coli was tested for potential UV/H2O2 treatment in DI water and online sensors were also integrated to monitor the destruction in real-time. Pilot-scale experiments were performed using a Trojan UVSwift SC reactor (Trojan Technologies, London, ON, Canada) at a flow rate of 1 gal./min (gpm). UV radiation and UV/H₂O₂ combination in E.coli cell suspensions resulted in a >6 log₁₀ reduction of the viable counts. Similar exposure to B.thuringiensis spores resulted in a 3 log₁₀ reduction in viable counts. Scanning electron microscopy of the treated samples revealed severe damage on the surface of most E.coli cells, yet there was no significant change observed in the morphology of the B. thuringiensis spores. Following UV/H₂O₂ exposure, the BioSentry sensor showed an increase in the unknown, rod and spores counts, and did not correspond well when compared to viable counts assays. Data from this study show that advanced oxidation processes effectively inactivate E. coli vegetative cells, but not B.thuringiensis spores which were more resistant to UV/H₂O₂.

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Kazkaz, Mohammad. "Compact Sensors for Evaluation the Thermal Comfort." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-364619.

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Teplota vzduchu je nejčastěji používaná k posouzení tepelného stavu vnitřního prostředí. Avšak teplota vzduchu sama o sobě, je v mnoha případech pro toto posouzení nedostatečná. Hlavním cílem disertační práce je vyhodnotit tepelný stav vnitřního prostředí a specifikovat parametry, které na něj mají vliv. Teplota vzduchu, střední radiantní teplota, rychlost vzduchu a vlhkost vzduchu jsou čtyři základní parametry, které určují tepelný stav vnitřního prostředí. Vzhledem k tomu, že tepelný stav prostředí závisí na mnoha aspektech, byly odvozeny veličiny, které zahrnují kombinovaný účinek několika nebo všech těchto parametrů k určení tepelného stavu prostředí. Jedná se např. o efektivní teplotu, teplotu kulového teploměru, operativní teplotu, ekvivalentní teplotu, PMV a PPD indexy... aj. V dnešní době existuje spousta vysoce přesných senzorů, které mohou zhodnotit tepelný stav vnitřního prostředí. Z důvodu jejich vysoké ceny jsou používané převážně pro účely výzkumu. Předkládaná práce se převážně soustředí na vývoj kompaktního deskového senzoru pro vyhodnocení tepelného stavu vnitřního prostředí. Zaměřuje se hlavně na nízkou cenu senzoru společně s dostatečnou přesností. K dosažení cíle této práce jsou provedeny následující postupy: • Analýza environmentálních faktorů ovlivňujících tepelný stav prostředí. • Studium dopadu teploty vzduchu, střední radiantní teploty a rychlosti proudění vzduchu na tepelné indexy: teplotu kulového teploměru a operativní teplotu. • Teoretické porovnání teploty kulového teploměru a operativní teploty. • Navržení, rozvoj a konstrukce nového deskového senzoru pro posouzení tepelného stavu vnitřního prostředí. • Navržení a konstrukce testovací komory pro porovnávání senzorů tepelného stavu prostředí. • Kalibrace zkonstruovaného senzoru měřením fyzikálních veličin charakterizujících tepelný stav prostředí. • Testy směrové závislosti vyvinutého deskového senzoru a porovnání s kulovým teploměrem v testovací komoře. • Srovnání teoretických řešení s provedenými měřeními v testovací komoře. Výsledkem této práce je vlastní teoretické srovnání teploty kulového teploměru a operativní teploty ve vybraném rozsahu teploty vzduchu, střední radiantní teploty a rychlosti vzduchu pro možnost hodnocení tepelného stavu vnitřního prostředí pomocí kulového teploměru. Hlavním výstupem je však navržení a zhotovení jednoduchého deskového senzoru, který by byl dostatečně přesný pro měření tepelného stavu prostředí. V rámci disertace byla postavena také testovací komora a bylo provedeno testování vyvinutého senzoru pomocí měřicího systému INNOVA.

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Jagolinzer, Scott R. "Design and Control of a Dynamic and Autonomous Trackless Vehicle Using Onboard and Environmental Sensors." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3173.

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The purpose of this thesis is to explore the current state of automated guided vehicles (AGVs), sensors available for the vehicles to be equipped with, control systems for the vehicles to run on, and wireless technology to connect the whole system together. With a technological push towards increasing automation and maximizing the possible throughput of systems, automated technology needs to improve for trackless and wireless systems such as vehicles that can be used to move loads in a vast array of applications. The goal of this research is to develop and propose improvements in both vehicle and control system design that allows for improved safety and efficiency. Right now the main issues are maneuverability of vehicles and control systems being adaptive enough to deal with connection issues between systems. While prolonged connection issues will result in a stoppage of operation of any system that relies on wireless communication, intermittent issues can also cause systems to have an emergency stop. I have looked into ways to offload tasks from the central system and allow the vehicles themselves to have more computational privileges such that they can operate in a semi-independent manner. The result is a proposed system that remedies or limits negative effects that currently cause issues with trackless vehicles and control systems working with remote systems that communicate via wireless means.

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Kim, Yongsig. "Characterization of the Arabidopsis Calcineurin B-like Calcium Sensors in Environmental and Developmental Signal Transduction." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/193680.

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In plants, the regulatory networks that have evolved to generate the appropriate cellular responses to external and internal stimuli often include a transient increase in intracellular calcium (Ca²⁺). One ten member, plant-specific family of Ca²⁺ sensing elements, the calcineurin B-like (CBL) protein family, is thought to relay the Ca²⁺ signal to downstream targets when plants experience an abiotic stress. The purpose of this study was to uncover critical functions of four CBL proteins. CBL10 was chosen for its distinct amino acid sequence and unique genomic structure among the CBL proteins. CBL1 and CBL9, generated by segmental duplication, were chosen based on their high level of amino acid identity. CBL8 was chosen based on its sequence and genomic structure similarities to SOS3/CBL4, the founding member of the CBL family. An Arabidopsis CBL10 knock-out insertion, cbl10-1, was isolated and found to have reduced stamen elongation, leading to male sterility. The mutant also showed growth arrest in aerial portions of the plant and developed chlorosis in response to increasing salt concentrations. Alternative pre-mRNA splicing generated five CBL10.2 variants whose transcript levels were regulated by cold or salt treatment, suggesting that CBL10 is involved in normal development and plant growth during abiotic stress via tight regulation of transcript levels. Phylogenetic analysis suggests that CBL1 and CBL9 may compensate for each other in the regulation of essential functions in the single mutant backgrounds. To investigate the crucial functions of these genes, a cbl1 cbl9 double mutant was generated. When grown under drought conditions, the double mutant was less sensitive to ABA, lost more water and produced more shriveled seeds than wild-type plants suggesting that both CBL1 and CBL9 play key roles in relaying drought stress signals during vegetative and reproductive growth. Because phylogenetic analysis and amino acid sequence comparisons suggest that CBL8 may function redundantly with SOS3/CBL4, a cbl4 cbl8 double mutant was generated. The cbl4 cbl8 double mutant phenocopied the sos3-1 (cbl4) mutant during salt and ABA treatments. CBL8 promoter activity in accessory cells of trichomes and root hairs suggests that CBL8 may have a function in development of these specialized epidermal cells.

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Silwana, Bongiwe. "Graphene supported antimony nanoparticles on carbon electrodes for stripping analysis of environmental samples." University of the Western Cape, 2015. http://hdl.handle.net/11394/5141.

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>Magister Scientiae - MSc
Platinum Group Metals (PGMs), particularly palladium (Pd), platinum (Pt) and rhodium (Rh) have been identified as pollutants in the environment due to their increased use in catalytic converters and mining in South Africa (as well as worldwide). Joining the continuous efforts to alleviate this dilemma, a new electrochemical sensor based on a nanoparticle film transducer has been developed to assess the level of these metals in the environment. The main goal of this study was to exploit the capabilities of nanostructured material for the development and application of an adsorptive stripping voltammetric method for reliable quantification of PGMs in environmental samples. In the study reported in this thesis, glassy carbon electrode (GCE) and screen-printed carbon electrode (SPCE) surfaces were modified with conducting films of nanostructured reduced graphene oxide-antimony nanoparticles (rGO-SbNPs) for application as electrochemical sensors. The rGO-SbNPs nanocomposite was prepared by Hummer`s synthesis of antimony nanoparticles in reaction medium containing reduced graphene oxide. Sensors were constructed by drop coating of the surfaces of the carbon electrodes with rGO-SbNPs films followed by air-drying. The nanocomposite material was characterised by: scanning and transmission electron miscroscopies; FTIR, UV-Vis and Ramanspectrosocopies; dc voltammetry; and electrochemical impedance spectroscopy. The real surface area of both electrodes were studied and estimated to be 1.66 × 10⁶ mol cm⁻² and 4.09 × 10³ mol cm⁻² for SPCE/rGO-SbNPs and GCE/rGO-SbNPs, respectively. The film thickness was also evaluated and estimated to be 0.36 cm and 1.69 × 10⁻⁶ cm for SPCE/rGO-SbNPs and GCE/rGO-SbNPs, respectively. Referring to these results, the SPCE/rGO-SbNPs sensor had a better sensitivity than the GCE/rGO-SbNPs sensor. The electroanalytical properties of the PGMs were first studied by cyclic voltammetry followed by indepth stripping voltammetric analysis. The development of the stripping voltammetry methodology involved the optimisation of experimental conditions such as selection of adequate supporting electrolyte, choice of pH and /or concentration of supporting electrolytes, deposition potential, deposition time, stirring conditions. The detection of Pd(II), Pt(II) and Rh(III) in environmental samples were performed SPCE/rGO-SbNPs and GCE/rGO-SbNPs at the optimised experimental conditions For the GCE/rGO-SbNPs sensor, the detection limit was found to be 0.45, 0.49 and 0.49 pg L⁻¹ (S/N = 3) for Pd(II), Pt(II) and Rh(III), respectively. For the SPCE/rGO-SbNPs sensor, the detection limit was found to be 0.42, 0.26 and 0.34 pg L⁻¹ (S/N = 3) for Pd(II), Pt(II) and Rh(III), respectively. The proposed adsorptive differential pulse cathodic stripping voltammetric (AdDPCSV) method was found to be sensitive, accurate, precise, fast and robust for the determination of PGMs in soil and dust samples. The simultaneous determination of PGMs was also investigated with promising results obtained. The AdDPCSV sensor performance was compared with that of inductive coupled plasma mass spectroscopy (ICP-MS) for the determination of PGM ions in soil and dust samples. It was found that though the metals could be determined by ICP-MS technique, it was limited from the standpoints of sensitivity, ease of operation and versatility compared to the AdDPCSV sensor. This study has show cased the successful construction and application of novel SPCE/rGO-SbNPs and GCE/rGO-SbNPs AdDPCSV sensors forthe determination of PGMs in environmental samples (specifically roadside dust and soil samples). The study provides a promising analytical tool for monitoring PGMs pollutants that are produced by automobiles and transported in the environment.

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Santos, Figueroa Luis Enrique. "New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest." Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/43216.

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El presente proyecto de investigación está enfocado al desarrollo de sensores químicos fluoro-cromogénicos, para la detección y determinación de especies químicas de interés biológico, industrial y medioambiental de forma selectiva y con alta sensibilidad. En forma general, se busca el diseñar nuevos sistemas sensores basados en compuestos (receptores) formados por dos unidades: una unidad coordinante que interacciona con el anión a determinar y una unidad generadora de señal que alerta del reconocimiento molecular efectuado. Durante este estudio se están preparando diversas moléculas receptoras funcionalizandas con grupos modificadores de estructura para evaluar su influencia sobre las capacidades de detección y selectividad como receptores de especies específicas en diferentes condiciones y medios. Las diferentes aproximaciones en prueba implican a su vez el diseño y síntesis molecular, así como el análisis de las diferentes señales ópticas producidas en el reconocimiento, con el fin de diseñar sistemas de alta eficacia y eficiencia, y con posibilidades reales de aplicación.
Santos Figueroa, LE. (2014). New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/43216
TESIS
Premiado

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K, C. Milan. "Applicability of Soil Moisture Sensors in Determination of Infiltration Rate." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1509217475534338.

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YU, JINSONG. "Development of Microfabricated Electrochemical Sensors for Environmental Parameter Measurements Applicable to Corrosion Evaluation and Gaseous Oxygen Detection." Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1206981091.

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Ogilvie, Iain R. G. "Novel fabrication techniques for microfluidic based in-situ oceanographic nutrient sensors." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/342947/.

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This work presents an investigation into the production of components for in-situ oceanographic nutrient sensors. These devices are based on a micro fluidic chip platform, taking the lab-on-a-chip (LOC) system concept out of the laboratory and into a real world environment. The systems are designed to provide data on nutrient concentrations in the ocean and as such are built from robust low cost materials designed for deployments from 24 hours to 3 months. This report focuses on the challenges faced in designing a micro fluidic system for these harsh deployment situations including a study of the relevant literature to indicate short falls in current technologies. The aim of this work was to develop the next generation of micro fluidic chip based nutrient sensors. A novel solvent vapour bonding technique has been developed for the production of polymer based micro fluidic chips which produces robust chips while simultaneously reducing the surface roughness of the substrates during bonding. This has allowed micromilling of polymer substrates to quickly and easily develop new chip designs with optical quality features. The surface reduction technology has enabled development of a method to integrate absorbance cells into tinted PMMA devices which is also discussed. Integration of polymer membranes to produce valve and pump structures is discussed and a novel bonding technique for chemically robust Viton R membranes is demonstrated. The final chapter includes a discussion on system topologies, concentrating on the need for high resolution sampling and the implications on system design that arise. A novel multiplexed stop ow system is demonstrated. Questions about the role of traditional micro fluidic components, such as mixers, in high-throughput low temporal response system designs are discussed and a micro fluidic mixer suitable for some of these systems demonstrated.

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Lo, Presti Maria. "Optical detection of chemical species of environmental and biological relevance using molecular sensors and hybrid materials." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/172664.

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[ES] La presente tesis doctoral titulada "Detección óptica de especies químicas de importancia ambiental y biológica utilizando sensores moleculares y materiales híbridos" se centra en el diseño, preparación, caracterización y evaluación de sensores químicos moleculares. El trabajo realizado se puede dividir en dos partes: (i) síntesis de sensores de cationes metálicos en disolución y (ii) síntesis y caracterización de nanopartículas híbridas orgánico-inorgánicas para el reconocimiento de especies químicas y biológicas. En el primer capítulo se introduce el marco en el que se engloban los fundamentos teóricos de la química supramolecular en que se basan los estudios prácticos realizados durante la presente tesis doctoral. A continuación, en el capítulo dos, se presentan los objetivos generales de la tesis. En el tercer capítulo se presenta un quimiodosímetro cromo-fluorogénico, capaz de detectar selectivamente cationes trivalentes entre cationes y aniones monovalentes y divalentes mediante una reacción de deshidratación en agua. En el cuarto capítulo se presenta una unidad (BODIPY) conectada electrónicamente con un macrociclo dithia-dioxa-aza. Las soluciones de acetonitrilo y agua-acetonitrilo 95: 5 v / v de la sonda mostraron una banda ICT en la zona visible y son casi no emisivas. Cuando se utilizó acetonitrilo como disolvente, la adición de Hg (II) y cationes metálicos trivalentes indujo un cambio hipsocrómico de la banda de absorción y mejoras moderadas de la emisión. Se obtuvo una respuesta altamente selectiva al utilizar medios competitivos como agua-acetonitrilo 95:5 v/v. En este caso, sólo el Hg (II) indujo un cambio hipsocrómico de la banda de absorción y una mejora marcada de la emisión. El quinto capítulo explora el desarrollo de sensores para berberina y amantadina. Dos moléculas de interés biológico por su uso como fármacos. Se han preparado tres sistemas de sensores basados en la aproximación de puertas moleculares. En concreto, sobre nanopartículas MCM-41 cargadas con rodamina B como unidad de señalización, se ha llevado a cabo la funcionalización con diversas aminas y el bloqueo de poros con cucurbituril CB7. Las aminas utilizadas son ii ciclohexilamina, bencilamina y amantadina. Los materiales obtenidos se han caracterizado por técnicas de difracción de rayos X y microscopía electrónica de transmisión confirmando la estructura mesoporosa de las nanopartículas. Los materiales preparados muestran una respuesta a la berberina y la adamantina, quitando el tapón y liberando el tinte fluorescente al medio. La respuesta de los materiales a las dos sustancias de interés (berberina y amantadina) depende de la estructura química de cada uno de los materiales en función de las constantes de afinidad entre el analito y CB7. Los resultados obtenidos abren el camino al uso de puertas moleculares como sensores de berberina y amantadina.
[CA] La present tesi doctoral titulada "Detecció òptica d'espècies químiques d'importància ambiental i biològica utilitzant sensors moleculars i materials híbrids" se centra en el disseny, preparació, caracterització i avaluació de sensors químics moleculars. El treball realitzat es pot dividir en dues parts: (i) síntesi de sensors de cations metàl·lics en dissolució i (ii) síntesi i caracterització de nanopartícules híbrides orgànic-inorgànics per al reconeixement d'espècies químiques i biològiques. En el primer capítol s'introdueix el marc en el qual s'engloben els fonaments teòrics de la química supramolecular en què es basen els estudis pràctics realitzats durant la present tesi doctoral. A continuació, en el capítol dos, es presenten els objectius generals de la tesi. En el tercer capítol es presenta un quimiodosímetro crom-fluorogénic, capaç de detectar selectivament cations trivalents entre cations i anions monovalents i divalents mitjançant una reacció de deshidratació en aigua. En el quart capítol es presenta una unitat (BODIPY) connectada electrònicament amb un macrocicle dithia-dioxa-aza. Les solucions de acetonitril i aigua-acetonitril 95:5 v/v de la sonda van mostrar una banda ICT a la zona visible i són gairebé no emisivas. Quan es va utilitzar acetonitril com a dissolvent, l'addició de Hg (II) i cations metàl·lics trivalents va induir un canvi hipsocròmic de la banda d'absorció i millores moderades de l'emissió. Es va obtenir una resposta altament selectiva a l'utilitzar mitjans competitius com aigua-acetonitril 95:5 v/v. En aquest cas, només el Hg (II) va induir un canvi hipsocròmic de la banda d'absorció i una millora marcada de l'emissió. El cinquè capítol explora el desenvolupament de sensors per berberina i amantadina. Dues molècules d'interès biològic pel seu ús com a fàrmacs. S'han preparat tres sistemes de sensors basats en l'aproximació de portes moleculars. En concret, sobre nanopartícules MCM-41 carregades amb rodamina B com a unitat de senyalització, s'ha dut a terme la funcionalització amb diverses amines i el bloqueig de porus amb cucurbituril CB7. Les amines utilitzades són ciclohexilamina, bencilamina i amantadina. Els materials obtinguts s'han caracteritzat per tècniques iv de difracció de raigs X i microscòpia electrònica de transmissió confirmant l'estructura mesoporosa de les nanopartícules. Els materials preparats mostren una resposta a la berberina i la adamantina, llevant el tap i alliberant el tint fluorescent a l'mig. La resposta dels materials a les dues substàncies d'interès (berberina i amantadina) depèn de l'estructura química de cada un dels materials en funció de les constants d'afinitat entre l'anàlit i CB7. Els resultats obtinguts obren el camí a l'ús de portes moleculars com a sensors de berberina i amantadina.
[EN] The present doctoral thesis entitled "Optical detection of chemical species of environmental and biological importance using molecular sensors and hybrid materials" focuses on the design, preparation, characterization and evaluation of molecular chemical sensors. The work carried out can be divided into two parts: (i) synthesis of metal cation sensors in solution and (ii) synthesis and characterization of hybrid organic-inorganic nanoparticles for the recognition of chemical and biological species. The first chapter introduces the framework that encompasses the theoretical foundations of supramolecular chemistry on which the practical studies carried out during this doctoral thesis are based. Next, in chapter two, the general objectives of the thesis are presented. In the third chapter, a chromium-fluorogenic chemodosimeter is presented, capable of selectively detecting trivalent cations by means of a dehydration reaction in water. The fourth chapter presents a new compound containing a BODIPY unit electronically connected with a dithia-dioxa-aza macrocycle. Acetonitrile and water-acetonitrile 95:5 v/v solutions of the probe showed an ICT band in the visible zone and were nearly non-emissive. When acetonitrile was used as a solvent, addition of Hg(II) and trivalent metal cations induced an hypsochromic shift of the absorption band and moderate emission enhancements. A highly selective response was obtained when using competitive media such as water- acetonitrile 95:5 v/v. In this case only Hg(II) induced a hypsochromic shift of the absorption band and a marked emission enhancement. The fifth chapter explores the development of sensors for berberine and amantadine; two molecules of biological interest due to their use as drugs. Three sensing systems based on a "molecular gate" approximation have been prepared. Specifically, MCM-41 nanoparticles were loaded with Rhodamine B as a signalling unit, functionalized with various amines and capped with cucurbituril CB7. The amines used are cyclohexylamine, benzylamine and amantadine., The materials obtained were characterized by X-ray diffraction techniques and transmission vi electron microscopy, confirming the mesoporous structure of the nanoparticles. The prepared materials showed a response to berberine and adamantine, which induced release of the fluorescent dye to the medium. The response of the materials to the two substances of interest (berberine and amantadine) depends on the chemical structure of the capping ensemble and it is a function of the affinity constants between the analyte and CB7. The results obtained open the way to the use of gated materials as berberine and amantadine probes.
We thank the Spanish Government (MAT2015-64139-C4-1-R) and Generalitat Valenciana (PROMETEOII/2014/047). M. L. P. thanks Generalitat Valenciana for her Grisolia fellowship. Thanks are also due to Fundação para a Ciência e Tecnologia (Portugal) for financial support to the Portuguese NMR network (PTNMR, Bruker Avance III 400-Univ. Minho), FCT and FEDER (European Fund for Regional Development)-COMPETEQREN- EU for financial support to the research centre CQ/UM [PEst-C/ QUI/UI0686/2013 (FCOMP-01-0124-FEDER-037302)], and a post- doctoral grant to R. M. F. Batista (SFRH/BPD/79333/2011).
Lo Presti, M. (2021). Optical detection of chemical species of environmental and biological relevance using molecular sensors and hybrid materials [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/172664
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Derrick, Douglas C. "Special-Purpose, Embodied Conversational Intelligence with Environmental Sensors (SPECIES) Agents: Implemented in an Automated Interviewing Kiosk." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/145272.

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I utilized a design science approach to create an automated kiosk that uses embodied intelligent agents to interview individuals and detect changes in arousal, behavior, and cognitive effort by using psychophysiological information systems. This dissertation achieves three primary purposes.First, I describe the creation of this new Information Technology artifact, discuss design choices, and show the completed prototype.Second, related to this new system, I propose a unique class of intelligent agents, which are described as Special Purpose Embodied Conversational Intelligence with Environmental Sensors (SPECIES). I outline a system model that frames the conceptual components of SPECIES agents, provide design principles for developing SPECIES agents, and discuss some of the research implications of the various components in the model.Third, based on the SPECIES paradigm, I present five studies that evaluate different parts of the model. These studies form the foundational research for the development of the automated kiosk. In the first study, participants interacted with an automated interviewing agent via a chat-based modality (108 participants). The study clearly demonstrates the strong, positive correlation of both response time and the number of times a message is edited to deceitful responses. The software developed became the heart of the kiosk. The second study evaluated changing human decision-making by including influence tactics in decision aids (41 participants). This paper-based decision experiment showed that framing decision aids as appeals to individuals' values possibly change individuals' decisions and was the basis for study 4. The third study examined human-computer interaction and how SPECIES agents can change perceptions of information systems by varying appearance and demeanor (88 participants). Instantiations that had the agents embodied as males were perceived as more powerful, while female embodied agents were perceived as more likeable. Similarly, smiling agents were perceived as more likable than neutral demeanor agents. The fourth study assessed how incorporating impression management techniques into embodied conversational agents can influence human perceptions of the system (88 participants). The impression management techniques proved to be very successful in changing user perceptions. Specifically, agents that performed self-promotion were perceived as more powerful, trustworthy and expert. Agents that performed ingratiation were perceived as more attractive. In the fifth study, I used an embodied agent to interview people who had either constructed a fake bomb and packed it into a bag or had only packed clothes into a bag (60 participants). The agent used eye-tracking technology to capture pupil dilation and gaze behavior. When combined with vocal measurements, the kiosk technology was able to achieve over 93% accuracy in one trial.

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Radhakrishnan, Praveen Kumar. "Stratified Arrays of Needle-Type Oxidation Reduction Potential Sensors." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1250709803.

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Beneditti, Cristina Aparecida [UNESP]. "Imagens multitemporais ALOS/PALSAR baseada em orientação a objeto na discriminação da cobertura da terra." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/86778.

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Made available in DSpace on 2014-06-11T19:22:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-30Bitstream added on 2014-06-13T19:07:52Z : No. of bitstreams: 1 beneditti_ca_me_prud.pdf: 3065249 bytes, checksum: b10d04069c7a91011443ee9fcf72ab9c (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Sensores ópticos são amplamente utilizados para mapeamento da cobertura da terra em escala local e pequenas regiões, com uma ampla variedade de aplicações, incluindo planejamento urbano, inventario agrícola e florestal, gerenciamento de bacias hidrográficas e monitoramento ambiental. Mapeamento de cobertura da terra com dados da banda L SAR tem focado primariamente em florestas e área úmidas de regiões tropical e boreal, com ênfase no monitoramento de desmatamento tropical e reflorestamento. No inicio de 2006, aquisições sistemáticas do ALOS PALSAR tem fornecido conjunto de dados multisazonais com alta resolução (12,5m), com potencial para substituir ou complementar os conjuntos de dados ópticos para mapeamento de cobertura da terra em regiões que a cobertura de nuvens é menos problemática, mas ainda um limitante para a variação sazonal da cobertura da terra. Este estudo avalia a utilização de dados PALSAR multitemporal, combinados com modelo digital de superfície (DSM) derivado do ALOS PRISM, para o mapeamento da cobertura da terra em uma região central do estado de São Paulo, Brasil. A área de estudo (22.5ºS 47.8 ºW) está situada na região oeste do reservatório de Barra Bonita, próximo a confluência dos rios Tietê e Piracicaba, com elevações variando entre 300 e 1000m. Os usos da terra dominante são agricultura ( cana de açúcar, cítricas e gramíneas) e florestal (eucaliptos). A vegetação natural é restrita a vegetação riparia, mata na front da cuesta e macrofitas aquáticas sazonais. Áreas urbanas presente na região são São Pedro e Aguas de São Pedro. Duas cenas PALSAR no modo Fine-Beam Single-polarization (FBS) (08 de abril de 2008 e 09 de janeiro de 2009...
Optical sensors are widely used for land cover mapping at local and small region scales, for a wide variety of applications including urban planning, forest and crop inventory, watershed management, and environmental monitoring. Land cover mapping with L-band SAR data has focused primarily on forest and wetland areas in tropical and boreal regions, with particular emphasis on monitoring tropical deforestation and regrowth. Beginning in 2006, systematic acquisitions of ALOS PALSAR have provided multi-season, near-global data sets at high (12.5 m) resolution, with the potential to substitute for or complement optical data sets for land cover mapping in regions where cloud cover is less problematic, but still limiting for seasonally varying land cover. This study evaluates the utility of multi-temporal PALSAR data, combined with a digital surface model (DSM) derived from ALOS PRISM, for land cover mapping at a site in central São Paulo state, Brazil. The study area (22.5ºS 47.8 ºW) is situated at the west end of the Barra Bonita Reservoir, at the entrance point of the Tietê River, with elevations ranging from about 300 to 1000 m. Dominant land uses are agriculture (sugar cane, citrus, pasture) and forestry (eucalyptus). Natural vegetation is largely restricted to riparian forest, forests on steep slopes, and seasonal aquatic macrophytes. Urban areas include the cities of São Pedro and Águas de São Pedro. Two PALSAR Fine-Beam Single-polarization (FBS) mode scenes (8 April 2008 and 9 January 2009... (Complete abstract click electronic access below)

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Lee, Jin-Hwan. "MEMS Needle-Type Multi-Analyte Microelectrode Array Sensors for In Situ Biological Applications." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1212146149.

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Vanarse, Anup. "Interfacing of neuromorphic vision, auditory and olfactory sensors with digital neuromorphic circuits." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2016. https://ro.ecu.edu.au/theses/1802.

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The conventional Von Neumann architecture imposes strict constraints on the development of intelligent adaptive systems. The requirements of substantial computing power to process and analyse complex data make such an approach impractical to be used in implementing smart systems. Neuromorphic engineering has produced promising results in applications such as electronic sensing, networking architectures and complex data processing. This interdisciplinary field takes inspiration from neurobiological architecture and emulates these characteristics using analogue Very Large Scale Integration (VLSI). The unconventional approach of exploiting the non-linear current characteristics of transistors has aided in the development of low-power adaptive systems that can be implemented in intelligent systems. The neuromorphic approach is widely applied in electronic sensing, particularly in vision, auditory, tactile and olfactory sensors. While conventional sensors generate a huge amount of redundant output data, neuromorphic sensors implement the biological concept of spike-based output to generate sparse output data that corresponds to a certain sensing event. The operation principle applied in these sensors supports reduced power consumption with operating efficiency comparable to conventional sensors. Although neuromorphic sensors such as Dynamic Vision Sensor (DVS), Dynamic and Active pixel Vision Sensor (DAVIS) and AEREAR2 are steadily expanding their scope of application in real-world systems, the lack of spike-based data processing algorithms and complex interfacing methods restricts its applications in low-cost standalone autonomous systems. This research addresses the issue of interfacing between neuromorphic sensors and digital neuromorphic circuits. Current interfacing methods of these sensors are dependent on computers for output data processing. This approach restricts the portability of these sensors, limits their application in a standalone system and increases the overall cost of such systems. The proposed methodology simplifies the interfacing of these sensors with digital neuromorphic processors by utilizing AER communication protocols and neuromorphic hardware developed under the Convolution AER Vision Architecture for Real-time (CAVIAR) project. The proposed interface is simulated using a JAVA model that emulates a typical spikebased output of a neuromorphic sensor, in this case an olfactory sensor, and functions that process this data based on supervised learning. The successful implementation of this simulation suggests that the methodology is a practical solution and can be implemented in hardware. The JAVA simulation is compared to a similar model developed in Nengo, a standard large-scale neural simulation tool. The successful completion of this research contributes towards expanding the scope of application of neuromorphic sensors in standalone intelligent systems. The easy interfacing method proposed in this thesis promotes the portability of these sensors by eliminating the dependency on computers for output data processing. The inclusion of neuromorphic Field Programmable Gate Array (FPGA) board allows reconfiguration and deployment of learning algorithms to implement adaptable systems. These low-power systems can be widely applied in biosecurity and environmental monitoring. With this thesis, we suggest directions for future research in neuromorphic standalone systems based on neuromorphic olfaction.

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Sendra, Compte Sandra. "Deployment of Efficient Wireless Sensor Nodes for Monitoring in Rural, Indoor and Underwater Environments." Doctoral thesis, Editorial Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/32279.

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Existen muchos trabajos relacionados con el diseño y desarrollo de nodos sensores, donde se presentan gran variedad de aplicaciones. Las redes de sensores inalámbricos pueden facilitarnos y mejorar algunos aspectos de nuestra vida diaria. Es fácil, pensar que si este tipo de dispositivo es tan beneficioso para nosotros y para el entorno donde vivimos, su precio debería ser relativamente barato. Pero podemos comprobar que esto no es así. ¿Por qué estos dispositivos son tan caros? ¿Sería posible desarrollar dispositivos con las mismas capacidades y precios más económicos? ¿Cómo puedo fabricar mis nodos sensores de bajo coste? Esta tesis responde a estas preguntas y muestra algunas de las muchas aplicaciones que los nodos sensores pueden tener. En esta tesis hemos propuesto (e implementado en algunos casos) el desarrollo de nodos sensores para la monitorización del medio, a partir de dispositivos de bajo coste. Para la implementación de un nodo sensor, y en definitiva la red que une a todos estos nodos, es importante conocer el medio donde trabajarán. A lo largo de este documento se presentan las investigaciones llevadas a cabo para el desarrollo de sensores en tres ámbitos de aplicación. En el primero de ellos, se desarrollan dispositivos multisenores para la monitorización del medio. La aplicación de las redes de sensores inalámbricas al medio natural, precisa un estudio de cómo se ven afectadas las señales, en función de la distancia, vegetación, humedad del ambiente, etc. Focalizamos nuestros desarrollos en la verificación de incendios en zonas rurales y en el control de plagas en viñedos donde la detección precoz de estos eventos genera elevados ahorros económicos. También proponemos el desarrollo de una red de collares sensores para ganado domestico, que nos ayudará a reducir y prevenir en muchos casos, los ataques de lobos y hurtos de crías. Por último, dentro de este grupo, presentamos una red permite detectar anomalía de los materiales en edificios y red de sensores que nos permite monitorizar las personas mayores o deficientes, que se mueven junto con un grupo, en una excursión o actividad. El segundo grupo de aplicaciones, hace referencia a la monitorización de espacios en entornos de interior. Para ello hemos analizado el comportamiento de las señales inalámbricas en diferentes escenarios. Los resultados, nos han permitido extraer un nuevo método de diseño de las redes inalámbricas en interiores. Nuestro método, permite definir la mejor ubicación de los dispositivos de red y nodos sensores en interiores con un ahorro en el número de sensores del 15%. Por último, se presenta el estudio sobre las comunicaciones subacuáticas basadas en las ondas electromagnéticas donde analizamos la dependencia de las comunicaciones subacuáticas en agua dulce en función de la frecuencia, temperatura, tasas de transferencia de datos y modulación. Relacionado con el medio subacuático, presentamos 2 propuestas. La primera de ellas hace referencia a la implementación de una red de sensores para granjas marinas que nos permite reducir la cantidad de residuos depositados en el lecho marino y reducir el porcentaje de comida desperdiciada. La segunda propuesta es el desarrollo de dos sensores oceanográficos que nos permitirían controlar la cantidad de comida y heces depositadas en el suelo y controlar la turbidez del agua de manera muy simple y económica Todos estos desarrollos y propuestas, han estado precedidos por un exhaustivo estudio sobre los problemas energéticos que las redes de sensores inalámbricas presentan y las técnicas que pueden emplearse, para prolongar la vida útil de la red y mejorar su estabilidad.
There are many works related to the design and development of sensor nodes which present several applications. Wireless sensor networks can facilitate and improve some aspects of our daily lives. It is easy to think that if this type of device is so beneficial to us and to our environment, its price should be relatively cheap. But we can see that this is not true. Why these devices are so expensive? Would it be possible to develop devices with the same capabilities and lower prices? How can I make my low-cost sensor nodes? This dissertation answers these questions and shows some of the many applications that sensor nodes may have. In this dissertation, we propose (and implement in some cases) the development of sensor nodes for environmental monitoring, from low-cost devices. For the implementation of a sensor node and network which joins all these nodes, it is important to know the environment where they will work. Throughout this dissertation, we present the research carried out for the development of sensors in three main application areas. In the first of these areas, we present multisensor devices developed for environmental monitoring. The application of wireless sensor networks to the environment requires a study of how signals are affected depending on the distance, vegetation, ambient humidity, etc. We focus our developments on the fire detection in rural areas and on the control of pests in vineyards where the early detection of these events generates high economic savings. We also propose the development of a sensor network which will help us to reduce and prevent wolves¿ attacks and theft in livestock. Finally, within this group, we present a network to detect material anomalies in building and a sensor network which allows us to monitor the elderly or disabled people who move along with a group on a tour or activity. The second group of applications is related to the monitoring of spaces in indoor environments. For this, we analyze the behavior of wireless signals in different scenarios. These results allowed us to extract a new method for designing wireless networks in indoor environments. Our method allows defining the best location of network devices and sensor nodes indoors saving 15% of the sensors needed. Finally, we present a study on underwater freshwater communications based on electromagnetic waves, where we analyze the dependency of underwater communications as a function of working frequency, temperature, data transfer rates and modulation. Related to underwater environment, we present two proposals. First one refers to the implementation of a sensor network for marine farms which allows us to reduce the amount of waste deposited on the seabed and reduce the percentage of wasted food. The second proposal is the development of two oceanographic sensors which allow us to control the amount of food and feces deposited in seabed and the water turbidity control in a very simple and inexpensive way. All these developments and proposals have been preceded by a comprehensive study on the energy problems in wireless sensor networks. We have also presented several techniques which can be used to prolong the network lifetime and improve its stability.
Sendra Compte, S. (2013). Deployment of Efficient Wireless Sensor Nodes for Monitoring in Rural, Indoor and Underwater Environments [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/32279
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Dissertations / Theses on the topic 'Environmental sensors'

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