Dissertations / Theses on the topic 'Electronic sensors'
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Cavanaugh, Curtis. "AN ADAPTIVE ELECTRONIC INTERFACE FOR GAS SENSORS." NCSU, 2002. http://www.lib.ncsu.edu/theses/available/etd-20020108-121219.
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CAVANAUGH, CURTIS C. An Adaptive Electronic Interface for Gas Sensors (Under the direction of H. Troy Nagle).This thesis focuses on the development of an adaptive electronic interface for gas sensors that are used in the NC State electronic nose. We present an adaptive electronic interface that allows for the accurate mapping of the sensor?s voltage output to sensor resistance profiles. The adaptive interface uses a linearized Wheatstone bridge in a constant current configuration. The balancing of the bridge and the adjustment of the subsequent gain stage is performed using programmable variable resistors. The programmable resistors are controlled by a LabVIEW® program. The same control program also determines and records all the resistor values in the interface circuit. The resistance of each sensor is accurately computed by LabVIEW® using the interface-circuit, resistor values, and the voltage output of the circuit. Compensating for sensor drift can be done in LabVIEW® by adjusting the programmable resistor values so that a zero-voltage output is produced during the reference cycle. By doing this zero adjustment between each ?sniff? of an odorant, the baseline drift can be minimized.A single channel of the adaptive electronic interface has been designed and tested. The interface can be calibrated so that it is 99% accurate when performing sensor resistance measurements.A new conducting polymer sensor chamber has also been designed and tested. The new radial flow sensor chamber was minimizes the dead volume in the chamber and also deliver the odorant to each sensor at the same time. Two operating modes were compared: continuous-flow and sniff-and-hold. Both modes gave good classification performance while testing four different coffee samples. Experimental testing indicates that sensor response is highly correlated with the sample flow rate. Future work to more fully characterize this correlation is recommended.
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Besrour, Marouen. "Wearable electronic sensors for vital sign monitoring." Master's thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/29543.
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On propose dans ce mémoire un nouveau type de capteur pour la mesure des fonctions respiratoires et cardiaques à des fins médicales. Le système offre la possibilité de mesurer le rythme respiratoire et la profondeur de respiration et de transmettre les données vers une station locale pour une analyse plus poussé et un diagnostic. Le capteur proposé est basé sur une approche électromagnétique où on utilise deux antennes posées sur la cage thoracique du patient. Lorsque le patient inspire et expire l’air avec ses poumons, le diamètre de la cage thoracique de ce dernier va augmenter et par conséquent la distance entre les deux antennes aussi. Le système mesure l’écart relatif entre les deux pour extraire le rythme respiratoire. Le point clé du capteur est d’encoder le signal de respiration sous forme de différence de phase entre l’onde émise et l’onde reçue conférant au système une bonne immunité contre les bruits des signaux externes. Le design a été implémenté sur un PCB (46mm x 46mm) pour fournir une preuve de concept de la méthode proposée. Les tests ont été conduits sur trois sujets de deux sexes et d’âges distincts. Les données mesurées démontrent que le système fonctionne sur différentes morphologies physiques. Finalement, le capteur a été capable de recueillir avec grande précision le rythme respiratoire et même la fréquence cardiaque.We propose in this project a wearable electronic Patch Radar sensor that can monitor respiration rate and respiration depth continuously in real-time and transmit data to a base station for analysis. The device relies on a two-antenna configuration. Both antennas are bent to the patient chest, and when the patient breathes, the mechanical movement of the chest wall changes the distance between them. The system measures the relative distance between the antennas to extract the respiration pattern. The key feature of the sensor is that it transduces respiration movements to phase shifts in RF wave signals which make it very robust against external interferences. The design was implemented on a PCB (46mm x 46mm) to demonstrate a proof of concept for the proposed device. The system was able to acquire respiration signals and even cardiac frequency. Experimental results are presented for three different subjects, an adult male and female and a child. The data gathered gives enough sensitivity and accuracy to state that the device can work with different physical morphologies.
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Zellers, Brian Andrew. "3D Printed Wearable Electronic Sensors with Microfluidics." Youngstown State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1575874880525156.
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Unander, Tomas. "System integration of electronic functionality in packaging application." Doctoral thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-14311.
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Sensor applications are becoming increasingly important as products are now being requested to be more and more intelligent and safe. As the costs involved in sensor technology decrease its usage will spread to new market segments including new areas with products that have never previously used such functionalities, including, wood fibre based products for packaging, hygiene or graphical use. Currently there is a significant interest in developing technology that will allow packages to become interactive and be integrated with digital services accessible on the Internet. In this thesis, the system integration of a hybrid RFID based sensor platform is presented. This proposed platform provides a trade-off between the communication performance and its compatibility with international standards and also includes flexibility in on‐package customization, including the type and number of sensors. In addition it combines the use of traditional silicon based electronics with printed electronics directly onto wood fibre based materials so as to enable the possibility of creating smart packages. Together with the system integration of the sensor platform, five printed moisture sensor concepts that are designed to work with the sensor platform are presented and characterized. Firstly, there is a moisture sensor that shows a good correlation to the moisture content of wood fibre based substrates. The second one involves a sensor that detects high relative humidity levels in the air and the third is an action activated energy cell that provides power when activated by moisture. The fourth one deals with two types of moisture sensors that utilize silver nano-particles in order to measure the relative humidity in the air. The final one is a printable touch sensitive sensor that is sensitive to the moisture contained in the hand. A concept of remote moisture sensing that utilizes ordinary low cost RFID tags has also been presented and characterized. The main focus is thus on system integration to, by combining silicon based electronics with printed electronics, find the most low cost solution with regards to flexibility, sensor functions and still meet the communication standards.När efterfrågan på mer intelligenta och säkra produkter ökar så ökar även intresset för olika typer av sensorer. När kostnaden för dessa sensorer sjunker så kommer användandet av dessa att utökas till nya marknadssegment som tidigare inte använt denna typ av funktionalitet, som tillexempel pappersbaserade förpackningar, hygienartiklar och papper för grafiskttryck. Det är för närvarande ett stort intresse att utveckla tekniker som tillåter förpackningar att bli interaktiva och integrerade med olika digitala tjänster kopplade till Internet. I denna avhandling så presenteras systemintegrationen av en RFID baserad sensor plattform som tillhandahåller en avvägning mellan kommunikationsprestanda, kompabilitet med internationella standarder och kundanpassningsflexibilitet. Där man direkt på förpackningen kombinerar fördelarna med traditionell kiselbaserad elektronik med trycktelektronik för att kunna skapa intelligenta förpackningar. I avhandlingen presenteras och utvärderas även fem trycka fuktsensorer som är designade att kunna användas tillsammans med sensor plattformen. Den första sensorn mäter fukthalten i cellulosabaserade substrat. Den andra kan detektera höga fukthalter i luften. Den tredje, som aktiveras vid en händelse, producerar en elektrisk ström när den blir fuktig. Den fjärde sensorn använder sig av silverbaserade partiklar i nanostorlek för att mäta fukthalten i luften. Den femte sensorn är en beröringskänslig sensor som ger utslag av fukten i handen. Utöver dessa sensorer så utvärderas även ett koncept med en fuktsensor som kan läsas av på avstånd. Fokus är således att på system integrationsnivå, med hjälp av att kombinera kisel elektronik med tryckt elektronik, hitta den mest kostnadseffektiva lösningen med avseende på flexibilitet, sensor funktionalitet och att även kunna möta kommunikationsstandarderna.
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Elliott, Joanne Margaret. "Conducting polymer odour sensors." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242764.
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Cooper, Christopher Robert. "Novel PET sensors." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368518.
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Norman, D. C. C. "Interrogation of fibre optic sensors." Thesis, Aston University, 2006. http://publications.aston.ac.uk/8022/.
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The aim of the research work described in this thesis was to investigate the interrogation of fibre optic sensors using "off the shelf optical components and equipment developed mainly for the telecommunications industry. This provides a cost effective way of bringing fibre optic sensor systems to within the price range of their electro-mechanical counterparts. The research work focuses on the use of an arrayed waveguide grating, an acousto-optic tuneable filter and low-coherence interferometry to measure dynamic strain and displacement using fibre Bragg grating and interferometric sensors. Based on the intrinsic properties of arrayed waveguide gratings and acousto-optic tuneable filters used in conjunction with interferometry, fibre Bragg gratings and interferometric sensors a number of novel fibre optic sensor interrogation systems have been realised. Special single mode fibre, namely, high-birefringence fibre has been employed to implement a dual-beam interrogating interferometer. The first interrogation scheme is based on an optical channel monitor, which is an arrayed waveguide grating with integral photo-detectors providing a number of amplified electrical outputs. It is used to interrogate fibre Bragg grating and interferometric sensors. Using the properties of polarisation maintainability in high-birefringent fibre an interrogating interferometer was realised by winding a length of the fibre around a piezoelectric modulator generating a low-frequency carrier signal. The system was used to interrogate both fibre Bragg grating and interferometric sensors. Finally, the use of an acousto-optic tuneable filter is employed to interrogate fibre Bragg gratings. The device is used to generate a very high frequency carrier signal at the output of an optical interferometer.
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Chen, Si. "Electronic Sensors Based on Nanostructured Field-Effect Devices." Doctoral thesis, Uppsala universitet, Fasta tillståndets elektronik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-194015.
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Point-of-care (POC) diagnostics presents a giant market opportunity with profound societal impact. In particular, specific detection of DNA and protein markers can be essential for early diagnosis of e.g. cancer, cardiovascular disease, infections or allergies. Today, identification of these markers often requires extensive laboratory work and hence is expensive and time consuming. Current methods for recognition and detection of specific biomolecules are mostly optics based and thus impose severe limitations as to convenience, specificity, sensitivity, parallel processing and cost reduction. Electronic sensors based on silicon nanowire field-effect transistors have been reported to be able to detect biomolecules with concentrations down to femtomolar (fM) level with high specificity. Although the reported capability needs further confirmation, the CMOS-compatible fabrication process of such sensors allows for low cost production and high density integration, which are favorable for POC applications. This thesis mainly focuses on the development of a multiplex detection platform based on silicon nanowire field-effect sensors integrated with a microfluidic system for liquid sample delivery. Extensive work was dedicated to developing a top-down fabrication process of the sensors as well as an effective passivation scheme. The operation mechanism and coupling efficiencies of different gate configurations were studied experimentally with the assistance of numerical simulation and equivalent circuits. Using pH sensing as a model system, large effort was devoted to identifying sources for false responses resulting from the instability of the inert-metal gate electrode. In addition, the drift mechanism of the sensor operating in electrolyte was addressed and a calibration model was proposed. Furthermore, protein detection experiments were performed using small-sized Affibody molecules as receptors on the gate insulator to tackle the Debye screening issue. Preliminary results showed that the directionality of the current changes in the sensors was in good agreement with the charge polarities of the proteins. Finally, a graphene-based capacitor was examined as an alternative to the nanowire device for field-effect ion sensing. Our initial attempts showed some attractive features of the capacitor sensor.
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Ioannides, Nicos. "Novel opto-electronic and plastic optical fibre sensors." Thesis, London Metropolitan University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287610.
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The design and performance of a novel displacement sensor is investigated both theoretically and experimentally. This is an optical, extrinsic and differential sensor based on the inverse square law and is insensitive to source intensity variations. It can, in principle, be implemented using only opto-electronic components or it can incorporate optical fibres to allow for EMI free and remote operation. The sensor is implemented using Plastic Optical Fibres (POF) as these offer considerable advantages over glass fibres or glass fibre bundles. The sensor head consists of three POFs positioned side by side and displaced from each other parallel to the axis of the sensor head by a separation X, (mm). The middle POF is coupled to a red LED and emits light onto a flat target with the two outer fibres receiving the reflected light from the target and guiding it to two silicon PIN photodiodes. Theoretical investigations on the behaviour of the sensor are presented for ranges between 0 mm and 100 mm, and for targets with different reflectivities. Non-linearities in the form of a spike are shown to exist in the very short ranges resulting in a minimum operational range of about 15 nun Beyond this minimum range the sensor response is linear and depends on the reflectivity of the target, the accuracy of calibration between the two detectors, any offset voltage present in any of the detectors, possible errors on the detected signals and the X, separation which in principle can be used to scale the sensor. Experimental results obtained confirm the long and linear operational range of the sensor (between 15 mm and 90 mm for a mirror target and between 20 mm and 100 mm for a matt white paper target). Likely variations in the source light intensity do not affect the performance and accuracy of the sensor. Measurements performed with various X, separations verify the scalability feature of the sensor in that by increasing X, one can achieve longer operational ranges. Temperature variations up to 40 °c do not affect the linearity of response. Effects arising from angular misalignment of the target and! or the ends of the three POFs are also investigated and could be minimised by rotating the emitting POF. Matt white paper is concluded as the preferred type of target since it offers a longer linear operational range with less stringent alignment requirements as opposed to reflective targets. Operation of the sensor under ambient illumination conditions is demonstrated using suitable electronic circuitry with filtering facilities. The result is a linear operational range of 60 mm with 1 % accuracy with a matt white paper target. An automated version of the sensor under software control is also demonstrated for monitoring large amplitude (0.15 mm - 6 mm), single degree vibrations. The maximum determined frequency of the vibrating surface is about 150 Hz and this is only limited by the target displacement which is close to the resolution limits of this version of the sensor (0.15 mm). This novel sensor offers considerable advantages over other sensors reported in the literature. It is shown to offer a very long and linear operational range in excess of 100 mm, with accuracy better than 1% and resolution better than 0.2 % of range, and currently this performance is only limited by the electronic circuitry used. Overall, the proposed sensor offers a superior sensor head arrangement and performance combination and its cost is expected to be very low. Suggestions for improvements and other applications are offered.
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Hodgins, Diana. "Vibrating solid-state sensors." Thesis, University of Hertfordshire, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314742.
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Simpson, Alexander George. "Optical fibre sensors and their interrogation." Thesis, Aston University, 2005. http://publications.aston.ac.uk/8006/.
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This thesis describes novel developments in the fabrication and understanding of type IA fibre Bragg gratings, the uses of said gratings as optical sensors and the interrogation of optical sensors using tilted fibre Bragg gratings. This thesis presents the most detailed study of type IA gratings performed to date and provides the basis of a dual grating optical sensor capable of independently measuring strain and temperature. Until this work it was not known how to reliably fabricate type IA gratings or how they would react to high ambient temperatures, nor was it known what effect external parameters such as fibre type, dopant levels, inscription laser intensity, or hydrogenation levels would have on the physical properties of the grating. This comprehensive study has yielded answers to all of these unknowns and produced several unexpected uses for type IA gratings, such as the use of the previously unreported strong loss band at 1400nm to locally heat fibres by optical absorption and thereby fabricate optically tuneable gratings which do not affect directly adjacent standard gratings. Blazed fibre Bragg gratings have been studied in detail and used to produce several high quality prototype sensor interrogation systems yielding stability an accuracy values unsurpassed by similar devices reported in literature. An accurate distribution map of light radiated by blazed gratings is shown for the first time and has been studied in respect of polarisation state showing that for certain easily achievable conditions a blazed grating spectrometer may be deemed to be polarisation insensitive. In a novel implementation of the system, it is shown that the dynamic wavelength range of a blazed grating spectrometer may be at least doubled by superimposing blazed gratings.
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Kritzinger, Pieter Christo. "The development of carbon nanostructured sensors." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5389.
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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: During this research the possibility of using carbon nanostructures in sensors were investigated. Graphene and carbon nanotubes (CNTs) are the nano- structures that were used in the developed sensors. Graphene is a single atomic layer of carbon and a carbon nanotube (CNT) is a rolled up sheet of graphene that forms a tube. The unique structure and incredible properties of both these materials make them ideal to be used in sensory applications. A graphene sensor was developed and experiments were performed to determine whether graphene is a viable candidate to be used in a wide range of sensory applications. The graphene sensor operated successfully as a humidity sensor and this led to the discovery that humidity can be used to control the bandgap in graphene. The absorption of CO2 in graphene was successfully measured using surface acoustic waves. As a result, any gas that graphene absorbs can be detected using this method. The use of graphene in three liquid applications was tested. The graphene showed no potential to be used as a pH sensor or as a ow sensor. An experiment was undertaken to determine whether graphene can increase the e ciency of a water electrolysis process, but it was established that the graphene does not make a signi cant di erence. A CNT gas sensor that identi es a gas based on its ionization characteristics was studied and designed. Due to the insu cient height of the grown CNTs, it was decided to focus on the creation of a model of the sensor that can be used to design it optimally. The results of the experiments con rmed that carbon nanostructures such as graphene and CNTs have potential to be used in future sensing applications.
AFRIKAANSE OPSOMMING: Hierdie navorsing ondersoek die moontlikheid om koolstof-nanostrukture in sensor-apparate te gebruik. Grafeen en koolstof-nanobuisies (KNB) is die nanostrukture wat in die ontwikkelde sensors gebruik is. Grafeen is 'n enkel atomiese koolsto agie en KNBs is 'n opgerolde grafeenlagie wat 'n buisie vorm. Die unieke struktuur en ongeloo ike eienskappe van beide hierdie materiale, maak hulle uiters geskik om in sensor-toepassings gebruik te word. 'n Grafeensensor is ontwikkel en eksperimente is uitgevoer om te bepaal of grafeen 'n goeie kanidaat is om in 'n wye verskeidenheid van toepassings gebruik te word. Die grafeensensor is suksesvol aangewend as 'n humiditeitsensor en dit het gelei tot die uitvindsel dat humiditeit gebruik kan word om die energiegaping in grafeen te varieer. Die absorpsie van CO2 in grafeen is suksesvol gemeet deur oppervlak akoestiese golwe te gebruik. Gevolglik kan enige gas wat grafeen absorbeer op hierdie manier gemeet word. Die gebruik van grafeen is in drie vloeistof-toepassings getoets. Die grafeen het geen potensiaal getoon om as 'n pH-sensor of as 'n vloei-sensor aangewend te word nie. 'n Eksperiment is ook uitgevoer om te toets of grafeen die e ektiwiteit van 'n water-elektroliese proses kan verhoog, maar die resultate het gewys dat dit nie 'n wesenlike verskil maak nie. 'n KNB-gassensor, wat 'n gas identi seer uit die ioniseerings eienskappe van die gas, is bestudeer en ontwikkel. Die lengte van die KNBs wat gegroei is, was onvoldoende en daar is gefokus op die ontwerp van 'n model van die sensor wat gebruik kan word om dit optimaal te ontwerp. Die resultate van die eksperimente het bevestig dat koolstof-nanostrukture soos grafeen en KNB baie potentiaal het om in toekomstige sensor-toepassings gebruik te word.
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Johnson, David Gary. "Integrating sensors and actuators for robotic assembly." Thesis, University of Hull, 1986. http://hydra.hull.ac.uk/resources/hull:11276.
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This thesis addresses the problem of integrating sensors and actuators for closed-loop control of a robotic assembly cell. In addition to the problems of interfacing the physical components of the work-cell, the difficulties of representing sensory feedback at a high level within the robot control program are investigated. A new level of robot programming, called sensor-level programming, is introduced. In this, the movements of the actuators are not given explicitly, but rather are inferred by the programming system to achieve new sensor conditions given by the programmer. Control of each sensor and actuator is distributed through a master-slave hierarchy, with each sensor and actuator having its own slave controller. A protocol for information interchange between each controller and the master is defined. If possible, the control of the kinematics of a robot arm is achieved through the manufacturer's existing control system. Under these circumstances, the actuator slave would be acting as an interface between the generic command codes issued from the central controller, and the syntax of the corresponding control instructions required by the commercial system. Sensor information is preprocessed in the sensor slaves and a set of high-level descriptors, called attributes, are sent to the central controller. Closed-loop control is achieved on the basis of these attributes. The processing of sensor information which is corrupted by noise is investigated. Sources of sensor noise are identified and new algorithms are developed to quantify the noise based on information obtained from the closed-loop servoing. Once the relative magnitudes of the system and measurement noise have been estimated, a Kalman filter is used to weight the sensor information and hence reduce the credibility given to noisy sensors; in the limit ignoring the information completely. The improvements in system performance by processing the sensor information in this way are demonstrated. The sensor-level representation and automatic error processing are embedded in a software control system, which can be used to interface commercial systems as well as purpose-built devices. An'industrial research project associated with the lay-up of carbon-fibre provides an example of its operation. A list of publications resulting from the work in this thesis is given in Appendix E.
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Taj, Murtaza. "Tracking interacting targets in multi-modal sensors." Thesis, Queen Mary, University of London, 2009. http://qmro.qmul.ac.uk/xmlui/handle/123456789/408.
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Object tracking is one of the fundamental tasks in various applications such as surveillance, sports, video conferencing and activity recognition. Factors such as occlusions, illumination changes and limited field of observance of the sensor make tracking a challenging task. To overcome these challenges the focus of this thesis is on using multiple modalities such as audio and video for multi-target, multi-modal tracking. Particularly, this thesis presents contributions to four related research topics, namely, pre-processing of input signals to reduce noise, multi-modal tracking, simultaneous detection and tracking, and interaction recognition. To improve the performance of detection algorithms, especially in the presence of noise, this thesis investigate filtering of the input data through spatio-temporal feature analysis as well as through frequency band analysis. The pre-processed data from multiple modalities is then fused within Particle filtering (PF). To further minimise the discrepancy between the real and the estimated positions, we propose a strategy that associates the hypotheses and the measurements with a real target, using a Weighted Probabilistic Data Association (WPDA). Since the filtering involved in the detection process reduces the available information and is inapplicable on low signal-to-noise ratio data, we investigate simultaneous detection and tracking approaches and propose a multi-target track-beforedetect Particle filtering (MT-TBD-PF). The proposed MT-TBD-PF algorithm bypasses the detection step and performs tracking in the raw signal. Finally, we apply the proposed multi-modal tracking to recognise interactions between targets in regions within, as well as outside the cameras’ fields of view. The efficiency of the proposed approaches are demonstrated on large uni-modal, multi-modal and multi-sensor scenarios from real world detections, tracking and event recognition datasets and through participation in evaluation campaigns.
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Barro, Alessandro. "Indirect TPMS improvement: sensor fusion with ultrasound parking sensors." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23765/.
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Pre-feasibility analysis on the optimization of the performance of the indirect tyre pressure monitoring system through a sensor fusion with a new generation of ultrasound parking sensors: from the idea to the development of macro project specifications and macro business case, with definition of the possible new scenario in
terms of performance, costs and perceived quality
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Besnard, Isabelle. "Improvement of conducting polymer gas sensors." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341716.
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Loday, Sylvie (Sylvie Johanna) 1977. "Electronic architecture and technoogy development of astronaut spaceflight load sensors." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/83679.
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Jabir, Saad A. A. "Thick film electronic ceramic sensors for civil structures health monitoring." Thesis, Edinburgh Napier University, 2011. http://researchrepository.napier.ac.uk/Output/4475.
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Buildings, roads, bridges and structures in general suffer many kinds of damages due to overstress caused by settlements of foundations, high winds, dynamic forces, passing traffic, vibration and unexpected external loads beyond the safe design forces. The damages manifest itself by cracks, falling of plaster and render uneven roads and some time complete collapse. The cost of maintaining and fixing damages caused by the above is quite high for the building and construction industry. The same phenomenon is common to many other structures like airplanes, wind turbine and machinery in general. Structural Health Monitoring (SHM) is the engineering branch, which aims to give, at every moment during the life of a structure, a diagnosis of the "state" of the constituent materials, of the different parts of a structure. The state of the structure must remain in the domain specified in the design, although this can be altered due to usage or due to normal aging by the action of the environment, and by accidental events. By using special electronic sensors to monitor the unexpected high concentration of stresses or changes of these stresses throughout the life of the structure and pavement, reduces the cost of maintenance and repair. Historic buildings would also benefit from using such sensors to monitor the overstress in the old and frugally stones and bricks. The sensors can be embedded in the lime mortar joints and an electronic meter is used periodically to check for any unusual overstress during the life of the building. The main aim of the proposed research project is to investigate the possibility of using thick-film technology stress sensors in masonry, concrete and building materials in general to monitor overstress and instability throughout the life of the structures. The sensors could be used in brick, block, stone, and concrete and they could be mounted on the surface or embedded in the materials. There are many research studies on strain gauge devices in structural monitoring; Thick Film (TF) piezo-resistive sensors are proposed as a direct alternative to the widely used metal Foil Strain Gauges (FSG). Due to the low cost of TF sensors, their ease of use, suitability to integrate electronics on board, and to have different geometrical shapes, they could be deployed at different locations in a building, road or be distributed in arrays. This offers the continuous monitoring of stresses at any time by using a data logger on two points on the surface or by using wireless electronic transmission. In this research, new thick film screen-printed ceramic piezo-resistive sensor has been developed and characterized as discrete device for deployment on surface of a structure and embedded into the structure during building material curing or after structure erection. The sensor response on different building materials has been experimented and compared. Mechanical and electronic simulation tools were used to characterise the sensor and to choose an adequate interface electronic circuit. The experimental results of the simulated sensor and circuitry, showed the suitability of the sensor to be embedded in building materials during curing period and on erected structures. Materials used were wood, concrete, brick and plaster. In addition, the overall linearity of response of the sensors applied on building material surface was asserted which makes the technology a candidate for a more wide deployment in SHM field.
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Northeast, David Bernard. "Hot electron bolometer sensors for millimetre-wave and terahertz wave detection." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6468.
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Thesis (MScEng (Electrical and Electronic Engineering))--Univerity of Stellenbosch, 2011.ENGLISH ABSTRACT: The design and simulation of hot electron bolometer sensors for the detection of millimeter and terahertz wave radiation is presented. These devices can be used for the formation of images or for spectroscopy in these frequency ranges. Many molecules resonate and have absorption spectra over these ranges, allowing for the identi cation, non-destructively and at a distance, of the constitution of many di erent materials. The penetrating ability of the radiation makes mm-wave and THz wave detectors ideal for security imaging. The design and simulation of these devices predicts performance as mixers and as interferometers. Manufacturing processes used while fabricating these thin lm devices are outlined and experimental results are reported.
AFRIKAANSE OPSOMMING: Hierdie tesis bespreek die ontwerp en simulasie van warm-elektron bolometers vir die waarneming van millimetergolf- en terahertz-straling. Sodanige toestelle kan in bogenoemde frekwensiebereike gebruik word vir beeldvorming of spektroskopie. Aangesien heelwat molekules binne hierdie bande resoneer, kan die samestelling van 'n verskeidenheid materiale oor 'n afstand en op 'n nie-vernietigende wyse gedenti seer word. Die deurdringingsvermo van millimetergolf- en terahertz-straling maak sulke detektors ideaal vir beeldvorming in veiligheidstoepassings. Met die ontwerp en simulasie van hierdie toestelle word gewys wat hul werkverrigting as mengers en interferometers kan wees. Die prosesse wat gebruik is om hierdie dun lmtoestelle mee te vervaardig word ook bespreek en eksperimentele resultate word aangebied.
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Jones, Alexander R. "The application of temperature sensors into fabric substrates." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/11991.
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Master of ScienceDepartment of Apparel, Textiles, and Interior Design
Diana Sindicich
With continuing advancements in the area of electronics, there are more ways in which they are utilized in order to improve the lives of humans. These advancements have to led to the incorporation of electronic components into fabric structures, creating electronic textiles (e-textiles). As it has become possible to place small electrical components within clothing without the performance of the electronics being hampered, research has been conducted in the use of e-textiles in measuring aspects of the human body, such as the heart rate and perspiration rate. In the area of skin temperature, research has been conducted in the past using e-textiles for skin temperature measurement, but past efforts have been unsuccessful in incorporating useable temperature sensors into a fabric substrate. This study compared three types of sensors incorporated into woven and knitted fabrics, using insulated thermocouples, un-insulated thermocouples, and resistance temperature directors (RTDs). Three incorporation methods (weaving, interlacing into knit, and stitching) were used in six fabric samples, with the three sensor types woven and stitched into three woven fabric samples, while the sensors were interlaced into knitted fabric and stitched into the three knitted samples. Fabric hand washing and temperature measurement tests were conducted, and the temperature readings were analyzed statistically for comparison. The analysis conducted showed that the thermocouples that were interlaced or stitched onto the knitted fabric samples were best for temperature measurement due to their accuracy and durability, while the RTDs were unusable as a temperature sensor, as the removal of the electrical connectors during washing eliminated the calibration that was established before washing. This research was supported in part by the Institute for Environmental Research at Kansas State University.
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Arab, Hassani Faezeh. "Resonant nano-electro-mechanical sensors for molecular mass-detection." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/336335/.
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This research is conducted as a part of EU FP7 project entitled NEMSIC (hybrid nanoelectro-mechanical/integrated circuit systems for sensing and power management applications) with project partners, EPFL, TU Delft, IMEC-NL, CEA-LETI, SCIPROM, IMEC-BE, Honeywell Romania, and HiQSCREEN. Nano-electro-mechanical (NEM) sensors are getting an increased interest because of their compatibility with “In-IC” integration, low power consumption and high sensitivity to applied force, external damping or additional mass. Today, commercial biosensors are developed based on mass-detection and electro-mechanical principles. One of the recent commercial mass-detection biosensors is a quartz crystal microbalance (QCM) biosensor which achieves the mass sensitivity of a few tens pico g/Hz. The newly developed in-plane resonant NEM (IP R-NEM) sensor in this thesis achieves the mass sensitivity less than zepto g/Hz that is over nine orders smaller than that of the commercial QCM sensor using a much smaller sensing area compared to the QCM sensor. This fact will make the IP-RNEM sensor a world-unique sensor that shows a very high sensitivity to a very small change in mass. The stated mass sensitivity is achieved by modelling the functionalization and detection processes of the suspended beam. For modelling the linker molecules in the functionalization process, a conformal coating layer in different configurations are added to the suspended beam and the sparse distribution of target molecules in the detection process is modeled by changing the density of the coating layer. I would like to clarify that the scaling rule of the mass responsivity is given by k4 regardless of the different functionalization configurations. I develop a completely new hybrid NEM-MOS simulation technology which combines three-dimensional finite element method (3D FEM) based NEM device-level simulation and circuit-level simulation for NEM-MOS hybrid circuits. The FEM device-level simulation module also includes new modelling of selfassembled monolayer for surface functionalization as well as adsorb ed molecules to be detected and facilitates quantitative evaluation of mass responsivity of designed NEM sensor devices. The basic part of the sensor, the NEM structure, includes a suspended beam and two side electrodes and that is fabricated at the Southampton Nanofabrication Centre (SNC). The fabrication at SNC includes a new sensor that uses a free-free beam that improves the quality factor up to five orders of magnitude at room temperature and atmosphere based on the numerical results. The IP R-NEM sensor consists of a suspended beam that is integrated with an in-plane MOSFET and is fabricated by CEA-LETI. The monolithically integrated NEM with the MOSFET on the same SOI layer for the sensor is a real breakthrough which makes it a potential low-cost candidate among the mass-detection based sensors. With respect to the conducted radio-frequency (RF) characterization for nano-wire devices in collaboration with the Tokyo Institute of Technology and NEM structures, the designing of an RF contact pad to reduce the effect of parasitic frequencies and doing the measurement at high vacuum to reduce the motional resistance and increase the quality factor are necessary for the characterization of devices with nano-scale dimensions. The integrated MOSFET in the IP RNEM sensor amplifies the output transmission signal from the resonating beam by its intrinsic gain. The fabricated sensors show a three orders of magnitude larger gain than that of the previously proposed resonant suspended gate FETs by biasing the MOSFET at the optimized voltage biases that are found based on the DC characterization of MOSFETs.
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Spångéus, Per. "New algorithms for general sensors, or, How to improve electronic noses /." Linköping : Univ, 2001. http://www.bibl.liu.se/liupubl/disp/disp2001/tek714s.pdf.
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Ameri, Ben. "Designing Laminate Composites to House Electronic Sensors for Drill Pipe Applications." Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/51892.
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This research demonstrated through technical evaluation and testing, that there is an optimum filament winding fabrication method for a composite material which will not compromise the material strength properties, when embedding electronic sensors within drill pipes manufactured from composite materials. A unique design and material selection analysis followed by this optimum fabrication process, allows the future development of ‘smart’ composite drill pipes.
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Lin, Ismael. "Combining dense short range sensors and sparse long range sensors for mapping." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-223572.
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Mapping is one of the main components of autonomous robots, and consist in the construction of a model of their environment based on the information gathered by different sensors over time. Those maps will have different attributes depending on the type of sensor used for the reconstruction. In this thesis we focus on RGBD cameras and LiDARs. The acquired data with cameras is dense, but the range is short and the construction of large scale and consistent maps is more challenging. LiDARs are the exact opposite, they give sparse data but can measure long ranges accurately and therefore support large scale mapping better. The thesis presents a method that uses both types of sensors with the purpose of combine their strengths and reduce their weaknesses. The evaluation of the system is done in an indoor environment, and with an autonomous robot. The result of the thesis shows a map that is robust in large environments and has dense information of the surroundings.Kartläggning är en av huvudkomponenterna för autonoma robotar, och består av att bygga en modell av miljön utifrån informationen som samlats in av olika sensorer över tid. Dessa kartor kommer att ha olika attribut beroende på vilken typ av sensor som används för rekonstruktionen. I denna avhandling är fokus på RGBD-kameror och LiDARs. Datan från kameror är kompakt men kan bara mäta korta sträckor och det är utmanande att konstruera storskaliga och konsistenta kartor. LiDARs är exakt motsatta, de ger gles data men kan mäta långa avstånd noggrant och stödjer därför storskalig kartering bättre. Avhandlingen presenterar en metod som använder båda typerna av sensorer i syfte att kombinera deras styrkor och minska svagheterna. Utvärderingen av systemet sker i en inomhusmiljö och med en autonom robot. Resultatet av avhandlingen visar en karta som är robust i stora miljöer och har tät information om omgivningen.
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Main, Andrew Stuart. "Low-cost interrogation of optical fibre Bragg grating sensors." Thesis, Aston University, 2007. http://publications.aston.ac.uk/8101/.
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Through the application of novel signal processing techniques we are able to measure physical measurands with both high accuracy and low noise susceptibility. The first interrogation scheme is based upon a CCD spectrometer. We compare different algorithms for resolving the Bragg wavelength from a low resolution discrete representation of the reflected spectrum, and present optimal processing methods for providing a high integrity measurement from the reflection image. Our second sensing scheme uses a novel network of sensors to measure the distributive strain response of a mechanical system. Using neural network processing methods we demonstrate the measurement capabilities of a scalable low-cost fibre Bragg grating sensor network. This network has been shown to be comparable with the performance of existing fibre Bragg grating sensing techniques, at a greatly reduced implementation cost.
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Van, Wyk Carel. "Markerless augmented reality on ubiquitous mobile devices with integrated sensors." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6790.
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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2011.ENGLISH ABSTRACT: The computational power of mobile smart-phone devices are ever increasing and high-end phones become more popular amongst consumers every day. The technical speci cations of a high-end smart-phone today rivals those of a home computer system of only a few years ago. Powerful processors, combined with cameras and ease of development encourage an increasing number of Augmented Reality (AR) researchers to adopt mobile smart-phones as AR platform. Implementation of marker-based Augmented Reality systems on mobile phones is mostly a solved problem. Markerless systems still o er challenges due to increased processing requirements. Some researchers adopt purely computer vision based markerless tracking methods to estimate camera pose on mobile devices. In this thesis we propose the use of a hybrid system that employs both computer vision and integrated sensors present in most new smartphones to facilitate pose estimation. We estimate three of the six degrees of freedom of pose using integrated sensors and estimate the remaining three using feature tracking. A proof of concept hybrid system is implemented as part of this thesis.
AFRIKAANSE OPSOMMING: Die berekeningskrag van nuwe-generasie selfone neem elke dag toe en kragtige "slim-fone" word al hoe meer populêr onder verbruikers. Die tegniese spesifikasies van 'n nuwe slim-foon vandag is vergelykbaar met die van 'n persoonlike rekenaar van slegs 'n paar jaar gelede. Die kombinasie van kragtige verwerkers, kameras en die gemaklikheid waarmee programmatuur op hierdie toestelle ontwikkel word, maak dit 'n aantreklike ontwikkelingsplatform vir navorsers in Toegevoegde Realiteit. Die implimentering van 'n merker-gebaseerde Toegevoegde Realiteitstelsel op selfone is 'n probleem wat reeds grotendeels opgelos is. Merker-vrye stelsels, aan die ander kant, bied steeds interessante uitdagings omdat hulle meer prosesseringskrag vereis. 'n Paar navorsers het reeds rekenaarvisie-gebaseerde merker-vrye stelsels aangepas om op selfone te funksioneer. In hierdie tesis stel ons die ontwikkeling voor van 'n hibriede stelsel wat gebruik maak van rekenaarvisie sowel as geintegreerde sensore in die foon om die berekening van kamera-orientasie te vergemaklik. Ons gebruik geintegreerde sensore om drie uit ses vryheidsgrade van orientasie te bereken, terwyl die oorblywende drie met behulp van rekenaarvisie-tegnieke bepaal word. 'n Prototipe stelsel is ontwikkel as deel van hierdie tesis.
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Cabrera, Sandra F. "Chemical sensors for urea and organophosphate nerve agents." abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3221401.
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Loh, Tzu Liang. "Integrated microfluidics, heaters, and electronic sensors for Lab-on-a-Chip applications." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32355.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.Includes bibliographical references (leaves 123-125).
Microfluidics, microfabricated suspended heaters and electronic field effect sensors have been successfully integrated on a single device chip. This integration enables spatial cycling of as little as 11nL of reagents over different thermally isolated temperature zones, to be coupled with the field effect sensing capabilities, for label-free detection of biomolecules such as DNA. The microfluidic valves provide control over reagent flow, and flow rates of up to 1.8nLs⁻¹ have been demonstrated with the on-chip pumps. Initial characterization of the suspended heaters was successfully carried out using thermochromic crystals. Functionality of the heaters was shown and a rough calibration was obtained. The subsequent implementation of temperature measurement using fluorescent dyes, enabled real-time spatial temperature mapping. This method demonstrated the capability of monitoring fluid temperatures in microfluidic channels with 5ÌC accuracy at 2[mu]m² resolution. Thermal isolation of the suspended heaters was clearly observed from the steep gradients in the spatial temperature profiles captured. Finally, localized boiling of water in the microfluidic channels was achieved, with only 30mW supplied to the heaters. In order to evaluate the sensors, tests were carried out to determine its sensitivity to surface charge. Buffer solutions of different pH were injected, and the sensors have been able to measure pH values ranging from 2.2 - 7.4 and demonstrate sensitivity of up to 38.8mV per pH unit change. Highly charged poly-electrolytes were also investigated as model systems to validate sensor detection of charged biomolecules.
(cont.) The adsorption and layer-by-layer deposition of multiple poly-electrolyte layers to the sensor surface have been successfully detected. This device paves the way for future integration of multiple microfluidic compo- nents, for lab-on-a-chip applications.
by Tzu Liang Loh.
S.M.
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Kahn, Mohammed Tariq Ekeramodien. "Miniaturised dedicated application opto-electronic sensors in the evolution of smart systems." Thesis, Peninsula Technikon, 2002. http://hdl.handle.net/20.500.11838/1196.
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Thesis (DTech (Electrical Engineering))--Peninsula Technikon, Cape Town, 2002In the last decade, the South Amcan Electricity Supply Commission would have had their ability to serve an ever demanding public severely tested. With the dilemma of providing electricity supply through hazardous environmental conditions, and with prospects of supplying power even beyond South Afiican borders, the need for a comprehensive damage and power delivery assessment strategy becomes all the more relevant. The rapid growth being made in the evolution of so called "intelligent" structures, with inherent sensor, actuator and control mechanisms built in can have direct influence on a power distribution network. At least in the foreseeable future, the impact ofphotonic sensors with inherent miniaturization, a foremost candidate in Smart System technology, can play a vital role in damage assessment of a potentially large network such as that found in the supply ofelectricity. Smart systems are nonliving systems that integrate the functions of sensing, actuation, logic and control, to respond adaptively to changes in their condition or environment to which they are exposed, in a useful and usually repetitive manner. Sensors are a fundamental part of the evolution of such systems and form the basis for the topic of this dissertation. The use ofoptical fiber sensors is increasing widely mainly due to their (a) miniature size, (b) remote signal processing ability, and (c) multiplexing capabilities. Because of the above features a variety of optical fiber sensing techniques has evolved over the years having potential for a myriad of applications. In this work a systems model and equations was developed for modeling the propagation of light in a optical waveguide, in order to study a Fabry Perrot sensor topology for application as a miniaturised sensor in a new type of smart structure, namely a smart electrical power system.
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Paszkiewicz, B., M. Wosko, R. Paszkiewicz, and M. Tlaczala. "Growth and characterization of algan/gan heterostructures for electronic devices and sensors." Thesis, Sumy State University, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20591.
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Tong, Jingbo. "MEASUREMENT AND MODELING OF HUMIDITY SENSORS." UKnowledge, 2014. http://uknowledge.uky.edu/ece_etds/59.
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Humidity measurement has been increasingly important in many industries and process control applications. This thesis research focus mainly on humidity sensor calibration and characterization. The humidity sensor instrumentation is briefly described. The testing infrastructure was designed for sensor data acquisition, in order to compensate the humidity sensor’s temperature coefficient, temperature chambers using Peltier elements are used to achieve easy-controllable stable temperatures. The sensor characterization falls into a multivariate interpolation problem. Neuron networks is tried for non-linear data fitting, but in the circumstance of limited training data, an innovative algorithm was developed to utilize shape preserving polynomials in multiple planes in this kind of multivariate interpolation problems.
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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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Chevatco, Vladimir. "Calibration of Vibration sensors - Evaluation and Effectivization." Thesis, KTH, Teknisk informationsvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215097.
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In this thesis, the calibration process of a geophone based vibration sensor istreated and optimised. The purpose of calibration is to estimate the physicalparameters of the system in the form of gain, damping and eigenfrequency.The geophone is calibrated on a shaker, and this thesis deals with the choiceof input signals and parameter estimation methods. Three dierent inputsignals are evaluated, and a new calibration process based on a multi-toneexcitation coupled with system identication methods for parameter estimationis proposed.I detta examensarbete studeras kalibreringsprocessen för ett geofon-baseratmätinstrument. Målet med kalibreringen är att skatta mätinstumentets egenskaperi form av egenfrekvens, dämpning och förstärkning. Instrumentet kalibreraspå ett skakbord och valet av insignal till skakbordet samt parameterskattningsmetodenbehandlas. Tre olika insignaler testas och en ny kalibreringsprocesssom använder multiton-insignaler och systemidentifieringför parameterskattning presenteras.
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Md, Noor Mohammad Faizuddin. "Machine learning techniques for implicit interaction using mobile sensors." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7723/.
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Interactions in mobile devices normally happen in an explicit manner, which means that they are initiated by the users. Yet, users are typically unaware that they also interact implicitly with their devices. For instance, our hand pose changes naturally when we type text messages. Whilst the touchscreen captures finger touches, hand movements during this interaction however are unused. If this implicit hand movement is observed, it can be used as additional information to support or to enhance the users’ text entry experience. This thesis investigates how implicit sensing can be used to improve existing, standard interaction technique qualities. In particular, this thesis looks into enhancing front-of-device interaction through back-of-device and hand movement implicit sensing. We propose the investigation through machine learning techniques. We look into problems on how sensor data via implicit sensing can be used to predict a certain aspect of an interaction. For instance, one of the questions that this thesis attempts to answer is whether hand movement during a touch targeting task correlates with the touch position. This is a complex relationship to understand but can be best explained through machine learning. Using machine learning as a tool, such correlation can be measured, quantified, understood and used to make predictions on future touch position. Furthermore, this thesis also evaluates the predictive power of the sensor data. We show this through a number of studies. In Chapter 5 we show that probabilistic modelling of sensor inputs and recorded touch locations can be used to predict the general area of future touches on touchscreen. In Chapter 7, using SVM classifiers, we show that data from implicit sensing from general mobile interactions is user-specific. This can be used to identify users implicitly. In Chapter 6, we also show that touch interaction errors can be detected from sensor data. In our experiment, we show that there are sufficient distinguishable patterns between normal interaction signals and signals that are strongly correlated with interaction error. In all studies, we show that performance gain can be achieved by combining sensor inputs.
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Soleimanpour, Amir Masoud. "Synthesis, Fabrication and Surface Modification of Nanocrystalline Nickel Oxide for Electronic Gas Sensors." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1365071722.
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Blair, Neil. "The development and characterisation of conducting polymer based sensors for use in an electronic nose." Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363297.
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Poopalasingam, Shivani. "Neural network based digital compensation schemes for industrial pressure sensors." Thesis, Coventry University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387520.
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Thong, Yee Keat. "A novel computer interface tool using low cost inertial sensors." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246360.
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Carbó, Cubero Paula. "Toward localization and mapping with heterogeneous depth sensors." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-286285.
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Heterogeneous collaborative Simultaneous Localization and Mapping (SLAM) can be defined as the solution to the SLAM problem that can handle different devices with different sensors, such as a monocular camera and a 3D LiDAR sensor, building a map and performing localization all at the same time. Research regarding this field is still at a very early stage, and it is hard to find solutions to the data association problem for these different types of sensor outputs. The increasing presence of devices and autonomous agents in our surroundings and everyday life is raising the question of how to make these very different devices collaborate. The goal of this thesis is to expand on previouswork regarding the use of SegMap as a map representation solution based on segmentation of point clouds that can handle heterogeneous data coming from sensor-specific and device-specific SLAM modules, and in this particular case, stereo and LiDAR data interchangeably. Stereo depth reconstructed point clouds do not share the same properties as LiDAR point clouds as is. Therefore, this thesis benchmarks the previous framework, introduces a new post-filtering module for stereo data that includes outlier filtering and point cloud registration, and finally shows results pointing out how the framework could be used robustly for heterogeneous place recognition.
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Taylor, Eric F. "Power delivery to remote sensors over optical fiber." abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1460784.
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Hendrickson, Benjamin William. "Dark Current RTS-Noise in Silicon Image Sensors." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4475.
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Random Telegraph Signal (RTS) noise is a random noise source defined by discrete and metastable changes in the magnitude of a signal. Though observed in a variety of physical processes, RTS is of particular interest to image sensor fabrication where progress in the suppression of other noise sources has elevated its noise contribution to the point of approaching the limiting noise source in scientific applications.
There have been two basic physical sources of RTS noise reported in image sensors. The first involves a charge trap in the oxide layer of the source follower in a CMOS image sensor. The capture and emission of a charge changes the conductivity across the source follower, altering the signal level. The second RTS source in image sensors has been reported in CCD and CMOS architectures and involves some metastability in the structure of the device within the light collection area.
A methodology is presented for the analysis of RTS noise. Utilizing wavelets, a time-based signal has white noise removed, while RTS transitions are preserved. This allows for the simple extraction of RTS parameters, which provide valuable insight into defects in semiconductor devices. The scheme is used to extract RTS transition amplitudes and time constants from radiation damaged CMOS image sensor pixels.
Finally, the generation of ionizing radiation induced RTS centers is investigated and discussed. Surprisingly, the number of RTS centers does not scale linearly with absorbed dose, but instead follows a quadratic dependence. The implications and possible mechanisms behind the generation of these RTS centers are discussed.
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Forsberg, Johan. "Mobile robot navigation using non-contact sensors." Doctoral thesis, Luleå tekniska universitet, EISLAB, 1998. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26184.
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This thesis concerns localization and control of mobile robots using range measurements from optronic sensors, in particular scanning time-of-flight lasers. The thesis covers the localization algorithms, on-line sensor calibration and tele-operation for semi-autonomous control of mobile robots. A real-world application of an autonomous mobile robot equipped with an arm for surface finishing operations is also developed. The Range Weighted Hough/Radon transform is introduced for robust detection of walls and extraction of geometric parameters. Thus a robot can automatically create a map of its environment and update it using an extended Kalman filter. The required association of observations with the map features uses a Bayesian classifier. New walls are added to the map as they are observed and classified as new. Navigation is performed with typical fluctuations of 1 cm and 1 degree (standard deviation) at speeds of 0.5 m/s. The navigation is robust even in cluttered environments and with several persons moving around. Sheet-of-light range cameras have also been tested for mobile robot navigation. A calibration algorithm for simultaneous calibration and localization integrates the calibration into the localization system. The only absolute reference needed by the calibration algorithm is the relative motion of the robot. The resulting system performs calibration during normal operation without lowering the localization performance. The algorithms above were applied to two applications: - A mobile robot capable of autonomously spray-plastering the walls and ceiling of a room. The prototype was successfully tested at construction sites. - A semi-autonomous robot tele-operated using tele-commands. The tele- commands include navigation along corridors, through open doors, following walking persons and automatic map generation of the remote site.Godkänd; 1998; 20061122 (haneit)
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Afaneh, Akef. "Computational investigations of the electronic structure of molecular mercury compounds: ion-selective sensors." Springer International Publishing AG, 2012. http://hdl.handle.net/1993/30661.
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This thesis presents the basic concepts of electronic structure theory and the chemical properties of mercury. The theoretical foundation of DFT and the consequences of relativity are also introduced. The electronic structure of Hg(II) ions, [Hg(L)n(H2O)m]q (L = HO-, Cl-, HS-, S2-) has been studied. We show, in this thesis, that the charge transfer (that is calculated from the hard-soft-acid-base principle (Pearson’s principle)), the total NBO charge and the interaction energies are strongly correlated. Our studies indicate the effect of the solvent on the global electrophilicity, the charge transfer and consequently the interaction strength between Hg(II) and ligand L. The formation constants, logK, of Hg2+−complexes are calculated. The procedure that we follow in this thesis to calculate the formation constants, logK’s, are in good agreement with the extrapolated experimental values. We introduce and explain why it is important adding water molecules explicitly during the calculations of the logK. The recommended logK value of HgS is 27.2. We examined two different types of organic compounds as sensors for heavy metal ions: lumazine (Lm) and 6-thienyllumazine (TLm). We found that the simple calculation of pKa values using DFT methods and implicit solvent models failed to reproduce the experimental values. However, calculated orbital energies and gas phase acidities both indicate that the compound TLm is inherently more acidic than the parent species Lm. We demonstrate that: (1) we need to take in our consideration the population of each tautomer and conformer during the calculations of the pKa values, and (2) thienyl group has indirect effect on the acidity of the proton on N1 in the uracil ring. Last but not least, the fluorescence spectrum of the sensors (L) and their [(L)nM(H2O)m]2+ complexes (L = Lumazine (Lm) and 6-thienyllumazine (TLm) and M = Cd2+and Hg2+) are calculated using time dependent DFT (TDDFT). The results show that TDDFT is in good agreement with experimental results. This chapter provides a new concept in the design of fluorescence turn-on/off sensors that has wider applicability for other systems. Finally, we provide a summary of the works compiled in this thesis and an outlook on potential future work.October 2015
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Collins, Gregory Earl. "New molecular electronic materials: Gas phase chemical sensors and organic molecular beam epitaxy." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/186045.
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The trivalent metallophthalocyanines, GaPc-Cl and InPc-Cl, have been investigated with respect to: (1) their possible application as gas-phase chemical sensor coatings for the detection of O₂, NH₃ and NO₂; and (2) the development of a new class of molecular electronic materials based upon the epitaxial growth of these large organic molecules. UHV analyses of InPc-Cl coated interdigitated array transducers have indicated that impurity phthalocyanines (such as FePc, MnPc and CuPc) have a dramatic impact upon the electrical nature and responsivity of these devices toward various gas analytes. Each of the different gas analytes examined, O₂, NH₃ and NO₂, were found to possess at least two different types of chemisorption sites on the surface of these organic films. Chemical sensor devices prepared and characterized under vacuum (including quartz crystal microbalance, surface acoustic wave and interdigitated array transducer devices), were also examined within an atmospheric sensing chamber in order to assess their ultimate feasibility as chemical sensors. The simultaneous monitoring of both electrical and microgravimetric changes within these devices allowed for complimentary information to be obtained concerning the chemisorption events taking place on the surface of these materials. Photoelectrochemical metal modification of the surface of these phthalocyanines provided a means for further enhancing the response of the chemical sensors toward NH₃, while a modification of the phthalocyanine surface with reducing agents such as polyvinyl ferrocene and MnPc provided an analogous enhancement in sensitivity to NO₂. The epitaxial growth of InPc-Cl has been demonstrated on both bulk SnS₂(0001) and MBE grown SnS₂ on muscovite. The optical absorbance and photoaction spectra obtained from these highly ordered phthalocyanine films have, in some cases, been found to be as narrow as the solution absorption spectra for these materials (FWHM = 40-60 nm). The epitaxial growth of CuPc, perylene tetracarboxylic dianhydride, C₆₀ and coronene were demonstrated on the MoS₂(0001) surface, with specific models developed to explain the nature of these organic overgrowths on the metal dichalcogenide surface. The formation of highly ordered heterojunctions or bilayer films based upon various combinations of these organic semiconductor materials has also been investigated as a precursor to the development of organic superlattice structures.
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Kamasani, Jyotheesh Reddy, Uday Suhas Nakkapalli, and Sai Jaswanth Yadala. "Arduino Based Home Electronics Labs : Basic- & Advanced-Electronics and Sensors Approaches." Thesis, Blekinge Tekniska Högskola, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-20034.
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Background. Engineering is incomplete without the practical knowledge so laboratories and practical experiments play a quite vital role in the study. Engineering requires both practical knowledge and skills along with theoretical background. However, new technology provides opportunity to perform experiments on distance or at home, what in current situation of COVID-19 pandemic has created a great motivation to have a deep study on distance education of Engineering. This report proposes the Home Labs for basic course in electronics. It shows both technical and educational approaches in terms of communication between a student and instructor. Objectives. The main objective of this project is to design and implement three labs of dedicated to basic electronics, linear integrated circuit and sensors. Each lab consists of five experiments. All experiments need to be accessed from home. Surveillance of lab results is one of the keys of the Home Labs, which cannot be compromised. Miniaturization of commonly used heavy lab equipment is one of the main project issue. Documentation of each and every experiment should be prepared in feasible way to help students to perform their experiments easily. The reporting template should also be easy to understand and implement. Methods. Most of the experiments apply Arduino as control unit. The microcontroller does not only control the experiments and connect it to the Internet as an element of IoT concept, but it also take responsibility for measurements and visualisation. The Arduino kit along with electronic components is owned by each student and could be handle anytime. Some extra components such as mini digital oscilloscope facilitate the experiments. Conclusions. Laboratories are the prime requirement of the Engineering Programs for developing students' practical skills. As implementation of all the experiments shows they can be done by not only real time lab equipment but also with miniaturized components. The proposed Home Lab budget was so friendly and economical compared to the campus labs. The Arduino based home electronic labs is the replica of the real time lab for the students who are doing their distance education and cannot have proper resource of the campus labs.
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De, Jager Nicolaas Jacobus. "The investigation and development of gas sensors with carbon nanomaterials." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/17872.
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Thesis (MScEng)--Stellenbosch University, 2011.ENGLISH ABSTRACT: In this research the possible utilization of carbon nanomaterials in gas sensing applications are investigated. These materials include the 2-dimensional honeycomb-lattice carbon structure called graphene, and the 1-dimensional structures referred to as carbon nanotubes (CNTs). The extraordinary properties and unique morphology of these nanomaterials, make them excellent candidates for sensory applications. This research thus entails the investigation and development of gas sensors with these carbon nanomaterials. This includes the synthesis of CNTs via a chemical vapour deposition (CVD) technique and the fabrication of resistive thin film sensors with the various materials. The functionalization of carbon nanomaterials is also explored, which delivers promising results for sensing gases at room temperature, especially acetylene (C2H2). Furthermore, a unique method is developed to fabricate ultra thin aluminium microstructures. These metallic electrodes are found to be ideal for nanomaterial integration. An experiment is performed to manufacture an integrated sensor with MWCNTs and following the results, a refinement of the procedure and the investigation of FET-based devices are recommended. The results obtained during this work, indicate that engineered carbon nanostructures, such as CNTs and graphene, can potentially be applied in future sensing technologies.
AFRIKAANSE OPSOMMING: Hierdie navorsing ondersoek die moontlike toepassing van koolstof nano-materiale as gas-sensor tegnologie. Hierdie materiale sluit die 2-dimensionele koolstof struktuur, grafeen, asook die sogenaamde 1-dimensionele koolstof nano-buise in. Die buitengewone eienskappe en unieke morfologie van hierdie nano-materiale, maak hul uitstekende kandidate vir sensor toepassings. Hierdie navorsing ondersoek dus die ontwikkeling van gas-sensors met koolstof nano-materiale, insluitend die sintese van koolstof nano-buise deur middel van ’n chemiese damp-neerslag proses, asook die fabrikasie van resistiewe dun film sensors. Die funksionalisering van koolstof nano-materiale is ook ondersoek en belowende resultate is opgelewer met betrekking tot die deteksie van gasse by kamertemperatuur, veral vir asetileen (C2H2) gas. Verder is ’n unieke metode ontwikkel om ultra dun aluminium mikrostrukture te vervaardig en hierdie metaal elektrodes word as ideaal beskou vir die integrasie van nano-materiale. ’n Eksperiment is uitgevoer om ’n geïntegreerde sensor te vervaardig met multi-wand koolstof nano-buise, waarvan die resultate aandui dat die proses verfyn moet word en dat die moontlike toepassing van veld-effek-transistor toestelle ondersoek moet word. Die resultate wat opgelewer is gedurende hierdie navorsing dui daarop dat ontwikkelde nanostrukture, soos koolstof nano-buise en grafeen, as toekomstige sensor tegnologie geïmplementeer kan word.
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Martins, Gilmar Antonio dos Santos. "Identificação de plásticos comerciais por meio de um nariz eletrônico baseado em polímeros condutores." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-31052011-152800/.
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O presente trabalho consiste no desenvolvimento de uma nova técnica de identificação de materiais poliméricos por meio do uso de um nariz eletrônico. Narizes eletrônicos têm sido desenvolvidos para detecção automática e classificação de odores e gases. São instrumentos capazes de medir a concentração ou intensidade odorante de modo similar a um olfatômetro, mas sem as limitações inerentes ao uso de painel humano, o que é altamente desejável. O nariz eletrônico é composto por um sistema de sensores, no nosso caso, utilizamos um arranjo de quatro sensores, que foram confeccionados pela deposição de finos filmes de polímeros condutores dopados sobre a superfície de eletrodos interdigitados. Estes sensores foram conectados a condutivímetros acoplados a um computador de uso pessoal (PC) através de um conversor AD. O PC era dotado de softwares de aquisição e tratamento de dados. Amostras dos materiais a serem analisados foram aquecidas a 257°C e o arranjo de sensores foi exposto aos compostos voláteis produzidos durante esse aquecimento. Realizaram-se 30 ensaios formados por períodos de exposição (5 segundos; compostos voláteis) intercalados por períodos de recuperação (45 segundos; ar puro). Os dados obtidos foram tratados estatisticamente por Análises de Componentes Principais (PCA). Esse arranjo de sensores mostrou-se eficiente, sendo capaz de diferenciar nove tipos de materiais poliméricos testados. Apresentou 100% de acerto em 30 ensaios de classificação realizados.This research consists in the development of a new technique capable of the identification of polymeric materials using an electronic nose. Electronic noses have been developed for automatic detection and classification of odors, vapors and gases. They are instruments capable of measuring the concentration or intensity of an odorant similarly to an olfactometer, but without the inherent limitations of the human panel, which is highly desired. The electronic nose is composed by a system of chemoresistive sensors, in this case, an array of four sensors was used, which were made through a deposition of thin films of doped conductive polymers, on the surface of interdigitated electrodes. These sensors were connected to conductivity meters coupled to a personal computer (PC) through AD converters. The PC had acquisition and data processing softwares installed on it. Thirty readings were made or each analyzed polymer consisting of alternated 5 seconds exposure periods and 45 seconds recovery periods. The collected data were statistically processed by Principal Component Analysis (PCA). This electronic nose was efficient, being able to identify nine types of polymeric materials through the analysis of the different volatile compounds released when these materials were heated to the heat of 257ºC. A 100% correct classification score was obtained in the 30 sets of analysis.
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Munoz, Torrico Max O. "Experimental characterisation of body-centric radio channels using wireless sensors." Thesis, Queen Mary, University of London, 2012. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8686.
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Wireless sensors and their applications have become increasingly attractive for industry, building automation and energy control, paving the way for new applications of sensor networks which go well beyond traditional sensor applications. In recent years, there has been a rapid growth in the number of wireless devices operating in close proximity to the human body. Wearable sensor nodes are growing popular not only in our normal living lifestyle, but also within healthcare and military applications, where different radio units operating in/on/off body communicate pervasively. Expectations go beyond the research visions, towards deployment in real-world applications that would empower business processes and future business cases. Although theoretical and simulation models give initial results of the antenna behaviour and the radio channel performance of wireless body area network (WBAN) devices, empirical data from different set of measurements still form an essential part of the radio propagation models. Usually, measurements are performed in laboratory facilities which are equipped with bulky and expensive RF instrumentation within calibrated and controllable environments; thus, the acquired data has the highest possible reliability. However, there are still measurement uncertainties due to cables and connections and significant variations when designs are deployed and measured in real scenarios, such as hospitals wards, commercial buildings or even the battle field. Consequently, more flexible and less expensive measurement tools are required. In this sense, wireless sensor nodes offer not only easiness to deploy or flexibility, but also adaptability to different environments. In this thesis, custom-built wireless sensor nodes are used to characterise different on-body radio channels operating in the IEEE 802.15.4 communication standard at the 2.45 GHz ISM band. Measurement results are also compared with those from the conventional technique using a Vector Network Analyser. The wireless sensor nodes not only diminished the effect of semi-rigid or flexible coaxial cables (scattering or radiation) used with the Vector Network Analyser (VNA), but also provided a more realistic response of the radio link channel. The performance of the wireless sensors is presented over each of the 16 different channels present at the 2.45 GHz band. Additionally, custom-built wireless sensors are used to characterise and model the performance of different on-body radio links in dynamic environments, such as jogging, rowing, and cycling. The use of wireless sensors proves to be less obstructive and more flexible than traditional measurements using coaxial cables, VNA or signal generators. The statistical analysis of different WBAN channels highlighted important radio propagation features which can be used as sport classifiers models and motion detection. Moreover, specific on-body radio propagation channels are further explored, with the aim to recognize physiological features such as motion pattern, breathing activity and heartbeat. The time domain sample data is transformed to the frequency domain using a non-parametric FFT defined by the Welch’s periodogram. The Appendix-Section D explores other digital signal processing techniques which include spectrograms (STFT) and wavelet transforms (WT). Although a simple analysis is presented, strong DSP techniques proved to be good for signal de-noising and multi-resolution analysis. Finally, preliminary results are presented for indoor tracking using the RSS recorded by multiple wireless sensor nodes deployed in an indoor scenario. In contrast to outdoor environments, indoor scenarios are subject to a high level of multipath signals which are dependent on the indoor clutter. The presented algorithm is based on path loss analysis combined with spatial knowledge of each wireless sensor.
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Danzeca, Salvatore. "The new version of the Radiation Monitor system for the electronics at the CERN : electronic components radiation hardness assurance and sensors qualication." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS196/document.
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La mesure des niveaux de rayonnement est une exigence essentielle dans le LHC et ses lignes d'injection afin de quantifier les effets des radiations sur l'électronique et de fournir une connaissance détaillée du champ de rayonnement. Le système de surveillance des rayonnements pour l'électronique au CERN, le "RadMon '', a été installé dans les zones critiques où l'équipement est ou sera placé. Les problèmes rencontrés au cours des dernières années d'utilisation du Radmon, et la nécessité d'améliorer la précision et la résolution des mesures a conduit au lancement d'une nouvelle conception du moniteur.Ce travail décrit l'architecture du nouveau RadMon (V6), sa fiabilité dans les environnements radiatifs et de la stratégie adoptée pour choisir et qualifier les capteurs utilisés pour surveiller le champ de rayonnement mixte des accélérateurs du LHC. Les directives du CERN ont été adoptées pour qualifier les composants RadMon sous rayonnement afin de développer une nouvelle architecture à la fois plus tolérante au rayonnement et plus polyvalente que celui de la version précédente. Dans ce contexte, les défis que les tests de rayonnement imposent pour mesurer les Single Event Upsets (SEUs) sur un composant complexe à signaux mixtes tels que le convertisseur analogique-numérique, ont conduit au développement d'une technique de test innovant, qui sera décrit dans cette thèse.L'environnement radiatif complexe du LHC impose un processus de qualification particulier qui sera décrit et discuté dans ce travail pour les RadFets (capteur dose ionisante) et les mémoires SRAM (capteur de fluence High Energy Hadrons).L'utilisation du RadFet dans un champ mixte de rayonnement a été étudié et analysé au moyen de sources de 60Co et de faisceaux de protons de différentes énergies.Les RadFets ont été ré-étalonné en étudiant le débit de dose, les sources de particules, la température, la guérison thermique en fonction de l'épaisseur d'oxyde. En outre, grâce à la nouvelle architecture de la RadMon, de nouvelles configurations de polarisation ont été testées pour améliorer la résolution.Deux types de mémoires SRAM avec des nœuds technologiques de 400 et 90 nm ont été testés et calibrés en suivant une méthode de qualification stricte qui comprend des tests protons,dans la plage de 30 à 400 MeV et neutrons, depuis les énergies thermiques jusqu'à des énergies intermédiaires (~ 14 MeV). La mémoire 90 nm améliore la précision et la résolution de la mesure de la fluence hadronique. En outre, l'utilisation simultanée des deux types de mémoires améliore la précision de la détection des neutrons thermiques par rapport à la version précédente, grâce à d'une procédure qui sera détaillée dans ce travail.Les efforts en vue de l'amélioration de la résolution des mesures de TID pour le nouveau RadMon conduisent à la recherche et à l'étude d'un nouveau type de dosimètre : le dosimètre a Grille Flottante (FGDOS). Le capteur intégrant une électronique complexe, une qualification complète sous rayonnement était nécessaire. Des tests en champ mixte, des tests au 60Co et des tests au protons ont été réalisés afin d'évaluer les performances et les problèmes potentiels du capteur. Dans ce contexte, un modèle analytique du capteur a été conçu pour démontrer que la structure à Grille Flottante pouvait être utilisée comme instrument de mesure du ‘charge yield' à température ambiante et sous des champs électriques faibles.La caractérisation de la tolérance au rayonnement du matériel, le processus de qualification et les étalonnages des capteurs ont considérablement amélioré la fiabilité globale et la qualité des mesures sur la nouvelle version du RadMon. Ces améliorations font du RadMon un instrument de référence pour la surveillance des rayonnements des champs mixtes complexes, tels que ceux rencontrés dans le LHC et sa chaîne d'injecteurs, mais aussi pour d'autres centres de recherche en physique des particules, comme JLAB aux États-Unis, J-PARC au JaponThe measurement of the radiation levels is an essential requirement in the LHC and its injection lines in order to quantify radiation effects on electronics and provide a detailed knowledge of the radiation field. The radiation monitoring system for the electronics at CERN, the “RadMon'', was installed in critical areas where equipment is or will be placed. Issues experienced in the last years of Radmon operation, the obsolescence of a few fundamental components of the electronic board and the necessity to improve both the accuracy and the resolution of measurements led to the launch of a new design of the monitor.This work describes the architecture of the new RadMon (V6), its reliability in radiation environments and the strategy adopted to choose and qualify the sensors, used for monitoring the mixed radiation field of the LHC accelerators. The CERN guidelines were adopted to qualify the RadMon components under radiation in order to develop a new architecture both more tolerant to radiation and more versatile than that of the previous version. In this context, the challenges that radiation tests impose for measuring Single Event Effects (SEUs) on a complex mixed-signal component such as the Analog to Digital converter, led to the development of an innovative test technique, which will be described in this thesis.The reliability of the RadMon measurements strongly depends on the calibration of its sensors. The complex radiation environment of the LHC imposes a peculiar qualification process which will be described and discussed in this work for the RadFets (Total Ionizing Dose sensor) and the SRAM memories (High Energy Hadrons fluence sensor).The use of the RadFet in a mixed field radiation environment has been studied and analyzed by means of 60Co sources as well as proton beams at different energies.The RadFets have been re-calibrated by studying the dose rate, particle sources, temperature, annealing and fading effects as a function of the oxide thickness. Furthermore, thanks to the new architecture of the RadMon, new biasing configurations have been tested to improve the resolution.Two types of SRAM memories with technology nodes of 400 and 90nm have been tested and calibrated by following a strict qualification methodology which includes tests with protons in the range 30-400 MeV, and with neutrons from thermal energies up to intermediate energies (~14 MeV). The 90nm memory improves the accuracy and resolution of the hadron fluence measurement. Moreover, the simultaneous use of both types of memories permits an improvement on the accuracy of the thermal neutron detection with respect to the previous version, as a result of a procedure which will be detailed in this work.The efforts towards the improvement of the TID measurements resolution for the new RadMon lead to the research and study of a new type of dosimeter sensor: the Floating Gate dosimeter (FGDOS). The sensor embeds complex circuitry, thus a full radiation qualification was necessary. Mixed field radiation tests, 60Co and protons tests have been carried out in order to evaluate the performance and the possible issues of the sensor. In this context, an analytical model of the sensor was developed to prove that the floating gate structure can be used as charge yield measurement instrument at room temperature and at low electric fields.The radiation tolerance characterization of the hardware, the qualification and calibration process of the sensors have significantly improved the overall reliability and quality of the measurements of the new RadMon. These improvements turned it into a reference instrument for radiation monitoring of complex mixed fields, such as the one encountered in the LHC, its injectors chain, and other particle physics research centers, such as JLAB in US, J-PARC in Japan
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Wu, Chi-Hao. "Enhancing the production performance of automotive sensor assembly lines through the statistical design of experiments." Diss., Online access via UMI:, 2008.
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Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Systems Science and Industrial Engineering, 2008.Includes bibliographical references.