Dissertations / Theses on the topic 'Tyre sensor'
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He, Mingzhe, and Xinyu Lin. "Connected Tyres : Real-time Tyre Monitoring System for Fleet& Autonomous Vehicles with Tyre WearEstimation through Sensor Fusion." Thesis, KTH, Fordonsdynamik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-290080.
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Tyres are one crucial part for vehicles, as they are the only contact pointbetween the vehicle and the road. Intelligent tyres are a trending new subjectin the tyre industry. They are designed to monitor various tyre states and sendthis information to both drivers and remote servers. The master thesis focuseson the proposal of a real-time tyre monitoring system for fleet and autonomousvehicles. It includes developing a tyre wear model and analysis of the currenttyre pressure monitoring functionality by leveraging the connectivity of fleetvehicles equipped with a Volvo web cloud service. The tyre wear model indirectlymonitors the tread depth of the vehicles all four tyres by identifyingcharacteristics between worn and fresh tyres. The two characteristics are identifiedby monitoring and analyzing vehicle speed and braking signals. The twocharacteristics is input to a voting scheme which decides when a worn tyre isdetected. The test vehicle was a Volvo XC40 with three types of tyres: wintertyres, summer tyres and worn summer tyres. The wear model gives 90 %accuracy to 10 set of test data, randomly selected from all dataset at HälleredProving Ground (Sweden). The connectivity realizes the data transmissionfrom the raw data of onCAN and FlexRay signals stored in a Volvo web cloudservice to the tyre monitoring fleet system. The signals are filtered and resampled,leaving the required signals of the tyre pressure monitor system andthe tyre wear model. Two signals, Calibration Status and iTPMS Status, areused to perform a statistical analysis on tyre pressure by categorizing the calibrationstatus and the tyre pressure conditions.The project outcome is an interfacebuilt on MATLAB GUI for demonstration of vehicle identification andtyre health conditions, with the embedded tyre wear model and connectivity.Däck är en viktig del för fordon, eftersom de är den enda kontaktpunktenmellan fordonet och vägen. Intelligenta däck är ett trendigt nytt ämne i däckindustrin.De är utformade för att övervaka olika däcktillstånd och skicka dennainformation till både förare och fjärrservrar. Examensarbetet är inriktat på ettförslag till ett däckövervakningssystem i realtid för fordonsflottor och autonomafordon och inkluderar en däckslitagesmodell och anslutning. Det inkluderaratt utveckla en slitagemodell och analys av den aktuella däcktrycksövervakningsfunktionengenom att studera Volvos fordonspark som är utrustade medVolvos webbmolntjänst. Däckens slitagemodell övervakar indirekt slitbanedjupetpå alla fyra däck genom att identifiera egenskaper mellan slitna och nyadäck. De två egenskaperna identifieras genom att övervaka och analysera fordonshastighet och bromssignaler. De två egenskaperna är inmatade i ett röstningsschemasom avgör när ett slitet däck upptäcks. Testfordonet var en VolvoXC40 med tre typer av däck, vinterdäck samt nya och slitna sommardäck.Modellen ger 90 % noggrannhet för 10 uppsättningar testdata, slumpmässigtvalda från alla dataset på Hällered provbana (Sverige). Anslutningen genomfördataöverföringen av rådata från onCAN och FlexRay-signaler lagrade ienVolvoswebbmolntjänst till däcksövervakningssystemet. Signalerna filtrerasoch samplas på nytt för att skapa de nödvändiga signalerna till däcktrycksövervakningssystemetoch däckslitagemodellen. Två signaler, kalibreringsstatusoch iTPMS-status, används för att utföra en statistisk analys av däcktrycketgenom att kategorisera kalibreringsstatus och däcktrycksförhållanden. Projektetsresultat är ett gränssnitt byggt på MATLAB GUI för demonstration avfordonsidentifiering och däcktillstånd. med inbäddad däckslitagemodell ochanslutning.
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Cao, Siyang. "Flexible bond wire capacitive strain sensor for a vehicle tyre." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6619/.
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This thesis reports a novel flexible wire bond structured capacitive sensor design that can measure the strain in the tyres stably and reliably without any influence or disturbance to the tyre material during the measurement. An industry achievable fabrication method based on the design has been also investigated and it is also believed that there is a possibility of introducing the sensor into mass production. Bond wire technology, laser machining technology and photolithography technology are adopted to fabricate the strain sensor, in which the wire bonding technology is the most significant process for this design. An array of 25 micrometer bond wires that are normally employed for electrical connections in integrated circuits is built to create an interdigitated structure and generating approximately 10pF capacitance. The array that in an approximately 8*8 mm area consists of 50 wire loops and creates 49 capacitor pairs. The aluminium wires are bonded to a flexible PCB which is specially finished to allow direct bonding to copper surface. The wire array is finally packaged and embedded in a flexible and compliant material, polydimethylsiloxane (PDMS), which acts as the structural material that is strained. The implementations of the bond wire, the flexible PCB and PDMS embedding minimize the stiffness of the strain sensor while the PDMS can also prevent the sensor from any potential damage. When a tensile strain occurs, the wires are stretched further apart reducing the capacitance. On the contrary, the wires move closer and increase the capacitance if the strain sensor is compressed. Different from the traditional interdigital capacitor, the capacitance of the device is almost in a linear relationship with respect to the strain, which can measure the strain up to at least ±60000 micro-strain (±6%) with the resolution of 111 micro-strain (0.01%).
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DI, MONACO FRANCESCO. "Product development methodologies for self-powered sensor-nodes in vehicle tyres." Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2534687.
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In this work the study of new product development methodologies is applied to modelling and simulation of several components of a tyre sensor node. The purpose of the sensor node is to improve the active safety of the vehicle making additional information, with respect to traditional TPMS, available to the vehicle dynamic control system. The components involved in the study are the rubber housing and the energy harvester. The rubber housing is a patch that ensures the bonding of the sensor on the tyre inner-liner, and its behaviour is simulated by means of a quasi-static FEM model where deformations and inertial loads are sequentially applied in a static simulation as a function of wheel rotation angle. The proposed method was validated by on-the-field testing. The energy harvester is a device designed to replace the batteries recovering energy from the environment. The performance of this device is studied using analytical techniques as well as numerical models. The reliability of the modelling techniques is confirmed through experimental testing in a controlled environment. The possibility of integrating semi-active controls in an energy harvester is also discussed and confirmed analytically and numerically.
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Stariak, Gabriel. "Tenzometrické závěsy kol Formule Student." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254217.
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The diploma thesis deals with examinations of forces which are acting from road surface on tyres. The aim is to design and build measuring circuit which measure forces in front suspension. The thesis deals with designing of mathematical model in addition describes problematic of strain gauge sensors, their calibration and verification measure in details. The results are data obtained from static and dynamic measurement and outputs from multi-body system softwares. The results are evaluated and compared at conclusion.
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Johnson, Simon. "Field effect transistor type sensors." Thesis, Cardiff University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259174.
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Stamm, Christoph Georg. "Integrated-optical difference interferometer as direct bio-chemical sensor, refractometer, and humidity sensor /." [S.l.] : [s.n.], 1994. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10943.
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Suzuki, Y., D. Ogura, M. Shikida, Y. Hasegawa, and K. Sato. "Development of Fabric-Type of Tensional Force Sensor." IEEE, 2009. http://hdl.handle.net/2237/13918.
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Amiri, Parian Jafar Parian Jafar Amiri. "Sensor modeling, calibration and point positioning with terrestrial panoramic cameras /." [S.l.] : [s.n.], 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17094.
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Naddafzadeh, Shirazi Ghasem. "Optimization in wireless sensor and machine-type communication networks." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46658.
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Wireless sensor networks (WSNs) are systems used for detecting events and gathering information from an area of interest in many different application domains, from home and industry automation, to healthcare and transportation, to environmental monitoring. With regard to the communication task involved in WSNs, they can also be seen as an instance of the new paradigm, known as machine-type communication (MTC). Similar to traditional wireless sensors, MTC-enabled devices can communicate together without direct human interference.
Energy efficiency for the sake of longevity is perhaps the most challenging requirement for many WSNs and MTC networks. In this thesis, we consider ultra-wideband (UWB) transmission technology for energy-efficient communication in WSNs. UWB achieves frugal use of energy by transmitting with low spectral efficiency when compared to legacy wireless technologies. This also allows it to operate license-exempt in many jurisdictions around the world. More recently, however, wireless service operators consider the use of cellular technology also for low data-rate applications originally only served by WSN-type technology. In particular, long-term evolution (LTE) technology has moved into the focus for joint personal-communication and MTC networks. Recent releases of the LTE standard and ongoing work items in LTE standardization specifically accommodate low-cost and low-power MTC.
This thesis presents contributions that improve the performance of UWB WSN and LTE MTC networks in several aspects, namely lifetime, localization accuracy, and coverage. A common theme of these different contributions are the use of optimization methods for obtaining scalable, robust, and/or low-complexity solutions.
We first address the lifetime maximization problem in a UWB-based WSN designed for multiple event detection. The key contribution is the joint optimization of transmission and routing parameters of sensor nodes so that the energy consumption is distributed as evenly as possible among the entire WSN. We then investigate the challenges of localization in WSNs and provide a convex solution which is robust to measurement uncertainties. In the last part of this thesis we focus on providing coverage for low-cost LTE MTC networks, where the challenge is to develop efficient transmission strategies that maximize the coverage of MTC devices in an LTE cell.
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Li, Jun. "VM-based event-processing in sensor networks." Zurich : ETH, Swiss Federal Institute of Technology, Department of Computer Science, Systems Group, 2008. http://e-collection.ethbib.ethz.ch/show?type=dipl&nr=380.
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Le, Xuqing. "Fire Detection Robot using Type-2 Fuzzy Logic Sensor Fusion." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32471.
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In this research work, an approach for fire detection and estimation robots is presented. The approach is based on type-2 fuzzy logic system that utilizes measured temperature and light intensity to detect fires of various intensities at different distances. Type-2 fuzzy logic system (T2 FLS) is known for not needing exact mathematic model and for its capability to handle more complicated uncertain situations compared with Type-1 fuzzy logic system (T1 FLS). Due to lack of expertise for new facilities, a new approach for training experts’ expertise and setting up T2 FLS parameters from pure data is discussed in this thesis. Performance of both T1 FLS and T2 FLS regarding to same fire detection scenario are investigated and compared in this thesis. Simulation works have been done for fire detection robot of both free space scenario and new facility scenario to illustrate the operation and performance of proposed type-2 fuzzy logic system. Experiments are also performed using LEGO MINDSTROMS NXT robot to test the reliability and feasibility of the algorithm in physical environment with simple and complex situation.
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Guggenbühl, Gasser Barbara Elisabeth. "Sensory and non-sensory assessment of consumer quality of apples /." Zürich : ETH, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17014.
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Boltshauser, Thomas. "CMOS humidity sensors /." [S.l.] : [s.n.], 1993. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10320.
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Hasegawa, Y., M. Shikida, D. Ogura, and K. Sato. "Glove Type of Wearable Tactile Sensor Produced by Artificial Hollow Fiber." IEEE, 2007. http://hdl.handle.net/2237/9569.
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Meyer, Jan. "Textile pressure sensor : design, error modeling and evaluation /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18050.
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Vogt, Harald. "Protocols for secure communication in wireless sensor networks /." Zürich : ETH, 2009. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18174.
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Yokota, T., J. Naito, M. Shikida, and K. Sato. "Micro-Machined Stent-Type Flow Sensor for Evaluation of Nasal Respiration." IEEE, 2009. http://hdl.handle.net/2237/13915.
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Arecco, Daniel. "Analysis and preliminary characterization of a MEMS cantilever-type chemical sensor." Digital WPI, 2004. https://digitalcommons.wpi.edu/etd-theses/806.
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This Thesis relates to the continually advancing field of microelectromechanical systems (MEMS). With MEMS technology, there are many different areas of concentration available for research. This Thesis addresses analysis and preliminary characterization of a cantilever-type MEMS chemical sensor for detection of chemicals and organic components operating at room temperature (20˚C and sea level pressure of 1 atm). Such sensors can be useful in a wide variety of applications. There currently exist several different types of MEMS chemical sensors. Each is based on a different detection method, e.g., capacitive, thermal, resistive, etc., and is used for specific tasks. Out of all currently available detection methods, the most common is the gravimetric method. The gravimetric sensor works by absorbing the chemical in a special material, usually a polymer, which alters the overall mass of the sensing element that can then be measured, or detected, to identify the chemical absorbed. One of the more exciting developments in the field of gravimetric chemical MEMS has been with the advancement of cantilever-type sensors. These cantilevers are small and usually on the order of only about 300 m in length. In order to utilize the gravimetric method, a cantilever is coated with a polymer that allows an analyte to bond to it and change its mass, which in turn changes the resonant frequency of the cantilever. The change in frequency can then be measured and analyzed and from it, the amount of absorbed mass can be calculated. Current research in the cantilever-type resonating sensors for the detection of hydrogen is developing measurement capabilities of 1 ppm (part-per-million). In this Thesis number of sample cantilevers were qualitatively assessed and their dimensional geometry measured. Based on these measurements, frequency data were obtained. In addition, the overall uncertainty in the resonant frequency results was calculated and the contributing factors to this uncertainty were investigated. Experimental methods that include laser vibrometry, optoelectronic laser interferometric microscopy (OELIM), and atomic force microscopy (AFM), were utilized to measure the frequency responses of the samples. The analytically predicted natural frequencies were compared to the experimental data to determine correlation subject to the uncertainty analysis. Parametric analyses involving chemical absorption processes were also conducted. Such analyses considered different parameters, e.g., damping and stiffness as well as changes in their values, to determine contributions they make to the quality of the frequency data and the effect they have on sensitivity of the MEMS cantilever-type chemical sensors. Once these parametric analyses were completed, it was possible to estimate the sensitivity of the cantilever, or the ability for the cantilever to detect frequency shifts due to absorption of the target chemical. Results of the parametric analyses of the fundamental resonant frequency were then correlated with the sensitivity results based on the chemical absorption. This Thesis correlates many results and ideas and probes problems revolving around the analysis and characterization of a MEMS cantilever-type chemical sensor.
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Fourie, Dehann. "Multi-modal and inertial sensor solutions for navigation-type factor graphs." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/114000.
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Thesis: Ph. D., Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science; and the Woods Hole Oceanographic Institution), 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 335-357).
This thesis presents a sum-product inference algorithm for in-situ, nonparametric platform navigation called Multi-modal iSAM (incremental smoothing and mapping), for problems of thousands of variables. Our method tracks dominant modes in the marginal posteriors of all variables with minimal approximation error, while suppressing almost all low likelihood modes (in a non-permanent manner) to save computation. The joint probability is described by a non-Gaussian factor graph model. Existing inference algorithms in simultaneous localization and mapping assume Gaussian measurement uncertainty, resulting in complex front-end processes that attempt to deal with non-Gaussian measurements. Existing robustness approaches work to remove "outlier" measurements, resulting heuristics and the loss of valuable information. Track different hypotheses in the system has prohibitive computational cost and and low likelihood hypotheses are permanently pruned. Our approach relaxes the Gaussian only restriction allowing the frontend to defer ambiguities (such as data association) until inference. Probabilistic consensus ensures dominant modes across all measurement information. Our approach propagates continuous beliefs on the Bayes (Junction) tree, which is an efficient symbolic refactorization of the nonparametric factor graph, and approximates the underlying Chapman-Kolmogorov equations. Like the predecessor iSAM2 max-product algorithm [Kaess et al., IJRR 2012], we retain the Bayes tree incremental update property, which allows for tractable recycling of previous computations. Several non-Gaussian measurement likelihood models are introduced, such as ambiguous data association or highly non-Gaussian measurement modalities. In addition, keeping with existing inertial navigation for dynamic platforms, we present a novel continuous-time inertial odometry residual function. Inertial odometry uses preintegration to seamlessly incorporate pure inertial sensor measurements into a factor graph, while supporting retroactive (dynamic) calibration of sensor biases. By centralizing our approach around a factor graph, with the aid of modern starved graph database techniques, concerns from different elements of the navigation ecosystem can be separated. We illustrate with practical examples how various sensing modalities can be combined into a common factor graph framework, such as: ambiguous loop closures; raw beam-formed acoustic measurements; inertial odometry; or conventional Gaussian-only likelihoods (parametric) to infer multi-modal marginal posterior belief estimates of system variables.
by Dehann Fourie.
Ph. D.
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Choi, Woo-Hyuck. "Needle-Type Sensor For In Situ 3-D Multi-Analyte Mapping." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1321641570.
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Arecco, Daniel. "Analysis and preliminary characterization of a MEMS cantilever-type chemical sensor." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0511104-150948.
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Thesis (M.S.)--Worcester Polytechnic Institute.Keywords: frequency; vibration; vibrometry; detection; resonance; micromechanical; polymer; absorption; AFM; SEM; holography; optoelectronic; silicon; hydrogen; palladium. Includes bibliographical references (p. 151-161).
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Wilson, Emma Rachel. "Cellular pathomechanisms in hereditary sensory neuropathy type 1." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/10037613/.
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Hereditary sensory neuropathy type 1 (HSN-1) is a peripheral neuropathy most frequently caused by missense mutations in the SPTLC1 or SPTLC2 genes, which code for two subunits of the enzyme serine palmitoyltransferase (SPT). SPT catalyzes the first and rate-limiting step of de novo sphingolipid synthesis. Mutations in SPT result in a change in enzyme substrate specificity, which generates two atypical products, deoxysphinganine and deoxymethylsphinganine, rather than the normal enzyme product, sphinganine. Levels of these abnormal compounds are elevated in the blood of HSN-1 patients and this is thought to cause the peripheral sensory and motor nerve damage characteristic of the disease. However, the mechanisms underlying nerve damage are largely unresolved and there remain no effective treatments. In this study, the cellular pathomechanisms that underlie the peripheral nerve damage in HSN-1 were examined using three in vitro models of disease. Firstly, primary motor and sensory neurons from wildtype mice were treated with either the typical enzyme product, sphinganine, or the atypical enzyme products, deoxysphinganine and deoxymethylsphinganine. The abnormal enzyme products were found to have dose- and time- dependent neurotoxic effects in both motor and sensory neurons. In addition, functional analyses revealed that the deleterious effects of the abnormal enzyme products may be mediated, at least in part, by abnormal calcium handling and mitochondrial dysfunction. In order to further explore the disease pathomechanisms and confirm whether these deficits were also present in models that more closely resemble the genetic aspect of this disease, two additional in vitro models were examined. In the first of these models, a lentiviral vector was generated in order to deliver wildtype and mutant SPTLC1 to primary motor and sensory neurons, and in the second, control and HSN-1 patient fibroblasts were obtained and examined. The results of this Thesis suggest that alterations in mitochondrial function and cellular calcium handling may contribute to the pathomechanism of HSN-1, and may therefore represent a potential target for therapeutic development.
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Lenggenhager, René. "CMOS thermoelectric infrared sensors /." [S.l.] : [s.n.], 1994. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10744.
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Correr, Wagner Rafael. "Development of impedimetric DNA sensor for diagnosis of Human Papillomavirus type 18 infection." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-05032015-144417/.
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Currently, the most common strategy employed to detect DNA sequences is PCR (Polymerase Chain Reaction). Nevertheless, in the last few years research on DNA biosensors has increased significantly. Such sensors represent an alternative to PCR in the detection of specific DNA sequences, once they exhibit fast response, low limits of detection, and require simpler sample preparation. The development of a biosensor for detection of DNA from Human Papillomavirus type 18 is reported. To immobilise DNA probe onto indium-tin oxide (ITO) electrodes, a silanisation was carried out using 3-Aminopropyltryethoxysilane (APTES). Silanisation was studied and optimised using ultra-violet absorption spectroscopy, atomic force microscopy, fluorescence microscopy, and cyclic voltammetry. After immobilisation, the hybridisation with target sequence is detected by changes in surface properties of ITO electrode by Cyclic Voltammetry and Electrochemical Impedance Spectroscopy, using the Ferri-Ferrocyante redox couple. The detection of synthetic target sequence was performed in the range of 12.5 to 100 nM, and 300nM for PCR products. The sensor did not show significative response for non-complementary sequence at 50 nM. This sensor can be applied for fast and low cost detection of HPV genetic material at nanomolar levels.A estratégia mais empregada atualmente na detecção de sequência de DNA é a PCR (Reação em Cadeira da Polimerase). Contudo, nos últimos anos, a pesquisa em biossensores de DNA tem aumentado significativamente. Estes sensores representam uma alternativa a PCR na detecção de sequências específicas de DNA, uma vez que exibem resposta rápida, baixos limites de detecção e requerem preparação simples da amostra. Nesta dissertação descrito o desenvolvimento de um biossensor para a detecção do DNA do Papilomavirus Humano tipo 18. A fim de imobilizar a sequência de captura de DNA em eletrodos de óxido de estanho e índio (ITO), realizou-se uma silanização usando 3-Aminopropiltrietoxisilano (APTES). A reação de silanização foi estudada e otimizada através das técnicas de Espectroscopia de Absorção Ultravioleta, Microscopia de Força Atômica, Microscopia de Fluorescência e Voltametria Cíclica. Após a imobilização, a hibridização com a sequência alvo é detectada através de alterações nas propriedades de superfície do eletrodo através de Voltametria Cíclica e Espectroscopia de Impedância Eletroquímica, usando o par redox Ferri-ferrocianeto. A detecção da sequência alvo sintética foi realizada no intervalo de 12.5 a 100 nM, e para o produto de PCR, 300 nM. O sensor não demonstrou resposta significativa para sequência não complementar a 50 nM. Este sensor pode ser aplicado na detecção rápida e de baixo custo de material genético do HPV a níveis nanomolares.
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Pant, Bharat Raj. "A Comparative Study on P-type Nickel Oxide and N-type Zinc Oxide for Gas Sensor Applications." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1525473245395728.
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Kasten, Oliver. "A state-based programming model for wireless sensor networks /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17397.
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Zhang, Chengyang. "Toward a Data-Type-Based Real Time Geospatial Data Stream Management System." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc68070/.
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The advent of sensory and communication technologies enables the generation and consumption of large volumes of streaming data. Many of these data streams are geo-referenced. Existing spatio-temporal databases and data stream management systems are not capable of handling real time queries on spatial extents. In this thesis, we investigated several fundamental research issues toward building a data-type-based real time geospatial data stream management system. The thesis makes contributions in the following areas: geo-stream data models, aggregation, window-based nearest neighbor operators, and query optimization strategies. The proposed geo-stream data model is based on second-order logic and multi-typed algebra. Both abstract and discrete data models are proposed and exemplified. I further propose two useful geo-stream operators, namely Region By and WNN, which abstract common aggregation and nearest neighbor queries as generalized data model constructs. Finally, I propose three query optimization algorithms based on spatial, temporal, and spatio-temporal constraints of geo-streams. I show the effectiveness of the data model through many query examples. The effectiveness and the efficiency of the algorithms are validated through extensive experiments on both synthetic and real data sets. This work established the fundamental building blocks toward a full-fledged geo-stream database management system and has potential impact in many applications such as hazard weather alerting and monitoring, traffic analysis, and environmental modeling.
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Lee, Hyoung Chul. "On the development of a batch type inclusion sensor in liquid steel." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28479.
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An inclusion sensor system for liquid metals first developed at McGill and dubbed with the acronym, LIMCA, is now in daily use for monitoring metal quality in ALCAN's casting centers. This method can simultaneously provide the number density, and size distribution, of inclusion particles in molten metals.Attempts have been made to extend the LIMCA technique to analyses of steel cleanliness. In order to commercialise the LIMCA system, a batch type probe, similar to an oxygen sensor, was developed and tested in low carbon steel melts.
For industrial applications, a series of experiments was carried out in a 60 ton tundish at DOFASCO. The data derived from these LIMCA measurements were compared to those obtained by DOFASCO personnel using the 'slime' technique for inclusion detection.
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Sahner, Kathy [Verfasser]. "Modeling of p-type semiconducting perovskites for gas sensor applications / Kathy Sahner." Aachen : Shaker, 2006. http://d-nb.info/1166513262/34.
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Shirzadfar, H., D. Kourtiche, R. Haraszczuk, M. Nadi, and S. Yamada. "Detecting and Estimating Magnetic Fluid Properties by a Needle- Type GMR Sensor." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/34967.
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Magnetic fluid or magnetic liquid are colloidal solutions of ultra-fine magnetic materials. Ferromagnet-ic materials consist of magnetic or other compound containing iron, nickel or cobalt, by a particle size of 5 to 50 nanometers, generally in a superparamagnetic, ferromagnetic or diamagnetic state. Magnetic fluids have a unique combination of strength and ability to interact with the magnetic field. This paper proposes to estimate and detect magnetic fluid weight density (concentration as low as 1%) by giant magnetore-sistance (GMR) sensor. The high sensitivity of the sensor is around 11 μV/μT. We propose to use it for bio-applications to characterize magnetic microfluides. For this application a Helmholtz coil was simulated and fabricated to make more uniform magnetic flux density.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34967
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Knecht, Wolfgang. "On nonlinear filtering for noise reduction using a sensor array /." [S.l.] : [s.n.], 1995. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11052.
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Radhakrishnan, Praveen Kumar. "Stratified Arrays of Needle-Type Oxidation Reduction Potential Sensors." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1250709803.
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Müller, Thomas. "An industrial CMOS process family for integrated silicon sensors /." [S.l.] : [s.n.], 1999. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13463.
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Avniel, Y. C. "Investigation of beta-alumina type electrolytes for use in high temperature sulphur detection." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338000.
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Gassmann, Felix. "Elektrooptischer Sensor für die isotrope Messung des elektrischen und magnetischen Feldes /." [S.l.] : [s.n.], 1995. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11190.
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Frey, Urs. "High-density neural interface and microhotplate gas sensor in CMOS technology /." Zürich : Physical Electronics Laboratory, ETH Zürich, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17460.
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Kocaman, Sultan Aksakal. "Sensor modeling and validation for Linear Array aerial and satellite imagery /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18120.
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Schneider, Michael Schneider Michael. "CMOS magnetotransistor and fluxgate vector sensors /." [S.l.] : [s.n.], 1999. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=12746.
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Pacitti, Elaine Grace. "The neuropharmacology of a slowly adapting type 1 sensory receptor." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/29930.
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The role of the Merkel cell-neurite complex in the transduction process in slowly adapting type 1 (SA1) cutaneous mechanoreceptors is unresolved. One hypothesis, based largely on the ultrastructure of Merkel cell-neurite complexes, suggests that chemosynaptic transmission occurs between the Merkel cell and its subjacent nerve terminal. This idea was investigated by mechanically stimulating SA1 mechanoreceptors exposed to pharmacologically active agents in several experimental preparations; an in vivo rat model, an in vivo feline isolated hind limb perfusion model and a novel isolated rat skin-nerve preparation. After exposure to the calcium channel blockers Mg2+ , Cd2+ and verapamil hydrochloride there was a dose dependent decline in the response of the SA1 mechanoreceptors to mechanical stimulation. Given that an influx of Ca2+ ions is required for stimulus-secretion coupling, these results support the hypothesis of chemosynaptic transmission. Immunohistochemical studies have shown that a met-enkephalin-like substance is associated with the dense cored vesicles in rodent Merkel cells. The idea that met-enkephalin was the transmitter substance in rat Merkel cell-neurite complexes was tested using the opiate antagonist naloxone and the agonist met-enkephalin in the isolated rat skin-nerve preparation. Met-enkephalin caused a dose dependent decline in the response of the SA1 mechanoreceptors to mechanical stimulation. This effect was antagonised by naloxone, indicating the presence of functional opioid receptors in the SA1 sensory receptor. However, this result indicates that met-enkephalin is not the excitatory transmitter substance in rat Merkel cell-neurite complexes, though it does have a modulatory role. The results presented in this thesis support the hypothesis that chemosynaptic transmission is involved in the transduction process in the Merkel cell-neurite complex.
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Albesa, Querol Joan. "Monitoring switch-type sensors and powering autonomous sensors via inductive coupling: application to removable seats in vehicles." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/101400.
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This thesis explores the feasibility of using inductive links for a vehicle application where wiring an electronic control unit (ECU) to the sensors or detectors become unfeasible or unpractical. The selected application is occupancy and belt detection in removable vehicle seats. Two ways of using inductive links are considered: 1) passive detection of the state of the seat detectors from a readout unit and 2) remote power transmission to a detection unit and subsequent data transmission by a wireless transceiver.
Inductive links have been widely proposed for sensors placed in harsh or inaccessible environments, where wiring is unpractical. Usually, the sensor forms part of an LC resonant network. The resonant frequency is dependent on the quantity to be measured and is estimated from a coupled reader. We propose the use of inductive links for switch-type sensors. First, a comprehensive analysis for an arbitrary number of sensors is presented. Secondly, we show the feasibility of using inductive links for occupancy and belt detection in removable vehicle seats. The state (open or closed) of the related sensors was attained by first measuring the equivalent resistance of the readout inductor and then estimating its resonant frequency. Commercial ferrite-core coils were used to increase the detection distance. Experimental tests were carried out using an impedance analyzer connected to the readout coil and commercial seat detectors connected to the resonant network. The detection of the sensors¿ state was feasible at all tested distances, from 0.5 cm up to 3 cm.
The second proposed alternative consists on remote powering, via an inductive link, the electronic device where the seat detectors are connected. Resonant coupled coils were used in order to increase the powering distance range and the power efficiency. Working frequency was restricted to 150 kHz. Commercial small-size magnetic-core coils were selected and their resistance and quality factor over frequency measured. At the receiving network, a rectifier and a voltage regulator were required to provide a DC voltage supply to the autonomous sensor. Four type of voltage regulators were compared from the point of view of the system power efficiency. Both a theoretical analysis and experimental results are presented. Results showed that shunt regulators provide the best power efficiency over the other alternatives, which are linear series and switching buck and boost regulators. On the other hand boost regulators led to an unstable behavior of the system in most of the cases. The use of rechargeable batteries was also considered in order to increase the power efficiency. Achieved power efficiencies were around 40%, 25% and 10% for coil distances of 1 cm, 1.5 cm and 2 cm respectively. Experimental tests also showed that the autonomous sensor was properly powered up to coil distances of 2.5 cm.
Finally, different types of coils were assessed and the effect of metallic structures analyzed for the intended application. The final aim is, on the one hand, to increase the powering distance and, on the other hand, to minimize the influence of the metallic structures. Three different coil types, two with ferrite-core coils and one with an air-core coil were used. Numerical results showed that ferrite-core coils are less affected by the presence of metallic structures. Experimental results showed that the air-core coils provided a larger powering distance thanks to its much larger winding diameter. However, when approaching a metallic plate, the transferred power with the air-core coils to the load was insufficient for the intended application. On the other hand, ferrite-core coils barely noticed the presence of the metallic plate. As for the passive detection, the presence of a metallic plate below the primary air-core coil slightly affected the measured resistance values but detection for the four possible states of the seat detectors was still possible.Algunes aplicacions a l'entorn de l'automòbil no són possibles si no és mitjançant la connexió sense fils dels seus dispositius a causa que el cablejat és difícil o inviable. Alguns exemples els trobem en el monitoratge de sensors situats en parts rotatòries, com les rodes, o en elements extraïbles, com els seients. Els sistemes de monitoratge de la pressió de l'aire en les rodes (TPMS) són d'obligat compliment als EUA i ho seran en breu també als països membres de la UE per als vehicles de categories M1 o N1 aprovats a partir de l'1 de novembre de 2012 o per als vehicles matriculats a partir de l'1 de novembre de 2014. Actualment, els sistemes TPMS existents al mercat estan alimentats per piles. Amb tot, la vida útil exigida per a les bateries és d'uns 10 anys, esdevenint el seu ús un autèntic repte. Un altre element en contra de l'ús de bateries és la directiva 2006/66/CE que limita el nombre màxim permès en els vehicles. D'altra banda, moltes furgonetes o mini furgonetes i vehicles familiars incorporen seients extraïbles amb l'objectiu d'aprofitar al màxim l'espai interior. Alguns models comercials incorporen en el seient extraïble el detector de cinturó de seguretat. Per evitar el cablejat, existeixen sistemes de detecció passiva mitjançant acoblament inductiu. A partir del present any 2012, una regulació de la agència nord-americana NHTSA requereix de l'ús de coixins de seguretat intel·ligents per minimitzar els riscos en nens. Aquests seients intel·ligents haurien de detectar si el passatger és un adult, una cadira infantil o si està lliure per evitar problemes ocorreguts en anterioritat amb els sistemes coixí de seguretat. Els sensors usats per a aquests coixins de seguretat intel·ligents requeririen d'energia per operar. Una opció per als seients extraïbles és la transmissió de potència via acoblament inductiu des del terra del xassís del vehicle fins al seient. També és possible usar l'acoblament inductiu per detectar l'estat de diversos sensors existents en els seients extraïbles mitjançant detecció passiva. Precisament, la detecció d'ocupació i de cinturó de seguretat en seients extraïbles ha estat seleccionada per aplicar la investigació present que consisteix, d'una banda, en el monitoratge de sensors de tipus commutat (dos possibles estats) via acoblament inductiu i, per una altra, en la transmissió mitjançant el mateix principi físic de la potència necessària per alimentar els sensors autònoms remots. En els dos casos, una primera bobina es fixaria en el seient extraïble, connectada als sensors, i una segona bobina se situaria sota la primera, en el terra del vehicle.
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Knüsel, Philipp. "Dynamic neuronal representations of static sensory stimuli /." Zürich : ETH, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16660.
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Brzeska, Malgorzata Dominika [Verfasser]. "RF Modelling and Characterization of Tyre Pressure Sensors and Vehicle Access Systems / Malgorzata Dominika Brzeska." Karlsruhe : KIT Scientific Publishing, 2015. http://www.ksp.kit.edu.
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Zheng, Wei-Ding, and 鄭惟頂. "Liquid refractive index measurements by uses of D-type multi-mode fiber sensors and the ATR prism type sensor." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/8e7s4a.
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碩士國立虎尾科技大學
光電與材料科技研究所
97
In this study, we propsed two methods for liquid refractive index measurements by uses of D-type multi-mode fiber sensors and the ATR prsim type sensor. 1. A multi-mode D-type optical fiber sensor based on the surface plasmon resonance(SPR), attenuated total reflection(ATR) and using optical spectrum analyzer method is presented. It is coated with an Au-film layer with a thickness of 20~50nm to detect the refractive variation of a liquid by measuring the output spectrum. Calculation of the reflectance ratio of the specimen, compared to water, enables determination of the resonant wavelength and the refractive index. The proposed method is used to enhance the measurement sensitivity and achieve a resolution to 5.2×10-7(RIU). 2 Being different with the usual SPR prism type sensor, a novel measurement system based on attenuated total reflection(ATR) with S polarization was built up in our Lab. For measuring the liquid refractive index, we used five-layers ATR sensors to simulate its attenuated angles corresponding different refractive index liquid and the best coating thickness. Comparing the resoulation between S- and P-polarizations, the S-polarized ATR sensor is better than the P-polarized SPR sensor, and the resoulation can achieve to 1.89×10-6 (RIU). The results exhibits that is feasibility to use S-polarization for measurement.
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Tang, Shao-En, and 唐紹恩. "Photo-sensor Type Touch Panel System." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/49787554456241323027.
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碩士國立臺灣大學
電機工程學研究所
96
Touch Panel Integration on Glass is a new proposal for recent display technology. The way to produce is to add photo-sensor structure in TFT Pixel Array, then to integrate touch panel function into 15 inch a-Si TFT-LCD panel, and to enable the display panel with Light-Pen Input Display or Finger Sensing Input Display function. We embedded a-Si photo sensors every 4 lines of gate lines and data lines into 15 inch LCD panel with resolution of XGA 1024x768 to let the sensor line resolution to reach 256x192. Either use fingers to block the light or use the light pen to put the strong light on the touch panel, we allow the touch panel create movements. When use fingers to block the ambient light it will have analog signal output, then through ADC to transfer analog signal to digital signal which is acceptable by computers. FPGA provides timing chart to analog board, through SPI interface to C8051, then through USB convey to PC, and the software touch control drivers in the computer will integrate all the components and edit them to calculate, finally show the position that users been touched on the screen. The biggest advantage of photo-sensor touch panel is to lower the cost, improve the transmittance, long lasting, reduce the thickness, and improve the calibration problems of capacitive touch panel.
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Tang, Shao-En. "Photo-sensor Type Touch Panel System." 2008. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-0707200816414300.
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LIANG, BO-HAO, and 梁博皓. "Pyroelectric-type entropy sensors." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/352525.
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碩士國立虎尾科技大學
機械設計工程系碩士班
106
In energy transformation systems, output energy is the most goal for increasing yield, consequently energy efficiency must be maximized. Entropy is a common parameter in chemical reactions, thermodynamic, biology and materials science, because energy loss is directly related to entropy generation. However, entropy generation in irreversible processes is difficult to be monitored in real time. Entropy can be an estimator for describing the failure and ageing of chemical, electrical or mechanical systems. The entropy rate can be derived from the induced pyroelectric current, temperature, thermal capacity, pyroelectric coefficient and electrode area. In the present study, a pyroelectric type entropy sensor is developed to evaluate entropy variation and rate while bulk PZT materials are fabricated with various thicknesses and dimensions by MEMS micromanufacture processes with a dicing saw and a sandblast etching machine. The entropy sensors are further applied to monitor capacitors for predicting they lifetime. The results show that increasing the PZT dimension raises the entropy variation. The increment of entropy variation is proportional to the volume of PZT cells. A PZT square with a 10 mm side length generates the entropy variation about 25 times than that of a 2 mm side length under the same PZT thickness of 100 μm. A PZT cell with a smaller volume cannot disturb the entropy generation of the measured objects, but the smaller electrode area can reduce the induced current and electrical signals increasing the difficulty in measurement. Moreover, the pyroelectric type entropy sensors are also successful to appraise the critical failure time in capacitors. The critical time is about 7.5s, 11.2.5s, 22.5s for the input voltage of 40V, 35V, 30V respectively while the commercial capacitor possesses the capacitance of 47μF and the maximum educed voltage of 4V.
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黃帥凱. "On the Improvement of Catalystic Type YSZ CO Sensor." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/57738375592283667502.
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碩士國立臺灣科技大學
化學工程系
92
Abstract The purpose of this study intends to obtain a better catalytic type YSZ CO sensor with shorter response time. The improvement was achieved by the following methods including changing the thickness of catalyst layer, printing different concentrated YSZ powder on electrode , doping different metal oxide into YSZ and changing calcinations time for the solid state electrolyte. SEM,XRD,ESCA and AC impedance were employed to characterize the catalyst layer and electrode. The influences of operating temperature and applied potential on the sensing were also studied. Based on the SEM, XRD and ESCA spectra, it was found that both Pt electrode and Cu/Zn catalyst layer were sintered after a long period operation. AC impedance analysis indicated that among all doing YSZ electrolyte the one doping with 1.0 wt% Sr gives the best oxygen ion conductivity. CO sensing data reveal that the best CO sensor with shortest response time(40-80 sec) is the one with printing 0.5 concentrated YSZ powder on electrode companying with doping 1.0 wt% Sr into YSZ. The experimental results also indicate that the sensitivity of the sensor can be improved by raising operating temperature as well as applied potential. The sensitivity would be raised from 0.0005 to 0.0033 μA/ppm CO when the operating temperature increase from 550 to 650℃,and from 0.0011 to 0.0027μA/ppm CO as applied potential increased from -0.5 to -1.0V.
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Chang, Kun-Hui, and 張琨揮. "A Current-type Gas Sensor Based on Substituted Phthalocyanines." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/70258850124782338191.
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碩士國立臺灣科技大學
化學工程系
90
Two substituted metallo-phthalocyanines, i.e. Copper(Ⅱ) 2, 9, 16, 23-tetra- tert-butyl-29H, 31H-phthalocyanine (CuttbPc) and Copper (Ⅱ) 3, 10, 17, 24- tetra-tert-butyl-1,8,15,22-tetrakis（dimethylamino）-29H, 31H-Phthalocyanine (CuttbtPc) were spin-coated onto alumina and fabricated into sensors for the detection of pollutant gases. The effects of operating parameters such as spinner speed, film thickness, substrate concentration, temperature and heat treatment on the sensing behavior were systematically investigated. It was found that the steady sate current of the CuttbPc sensor increases with the increase of SO2 concentration, operating temperature and film thickness. This sensor possesses satisfactory stability and reproducibility toward sensing SO2. Heat treatment profoundly affects the sensing characteristics of CuttbPc. While CuttbtPc, due to its strong electron-donating group which decreases the energy gap, can sense SO2 at a lower temperature of 90℃, as compared to 120℃ for CuttbPc.
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耿培倫. "Experiment in Water Level Measurment Using Resistent Type Sensor." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/28818031222840235151.
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碩士逢甲大學
土木工程學系
101
The observation instruments in water level measurement was restricted by different environments and setting patterns. To measure level and depth of water, the study had been designed 30 groups of resistent type sensors with combination of 5 negative electrodes, 2 types of screw cap and 3 electrode gaps. It was found that the use of resistent type sensor was effective in water level measurement. According to the experimental results, the readings of resistance value between 820-830 showed that the measurement position was between the air and water. The stability of measurement was not affected by material and space of electrode gaps. The assessment results of experiment showed that ; 1.Discrimination in water interfaces can be correctly identified by using average method. 2.The recognition rate of discrimination in simulated river bed material was 97%. The experimental group A.N20, B.N10 and D.N2 showed high efficacy in water depth measurement using resistent type sensors. Keyword：Water level measurement, Water depth measurement Water level Sensor, Water Monitoring Systems.
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Tsai, Yan-Ying, and 蔡衍穎. "Investigation of Schottky Contact-Type Hydogen Sensors." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/66388166434655362685.
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博士國立成功大學
微電子工程研究所碩博士班
96
In this dissertation, a series of Schottky contact-type hydrogen sensors are proposed. By using the catalytic metals (Pd or Pt) as the gate materials, the hydrogen molecules will be dissolved as hydrogen atoms. Part of those hydrogen atoms will diffuse through the metal bulk and adsorb at the metal-oxide or metal-semiconductor interface. Those adsorbed hydrogen atoms will be polarized to form a dipolar layer. Due to the presence of this dipolar layer, the significant changes in current-voltage characteristics of the studied devices are found. Experimentally, the studied hydrogen sensors can work in a low hydrogen concentration, high operating temperature, and wide hydrogen concentration range environments. Also, a short response time is observed in real-time applications. These results demonstrate the promise of the studied devices to perform as fast-responsive and sensitive hydrogen sensors over a broad range of operating temperature. In chapter 2, the Pt-InAlP metal-oxide-semiconductor and metal-semiconductor Schottky diode hydrogen sensors with high-sensitive hydrogen detection among wide operating temperature regime are comprehensively studied and compared. Experimentally, both the hydrogen sensors can be operated systematically under bi-polarity biases. In addition, it is worth to note that even an extremely low hydrogen concentration of 4.3 ppm H2/air can be effectively detected at the temperature of 30~250oC. The detecting sensitivity of the MOS-type hydrogen sensor is superior to that of the MS-type. It is believed that a high-quality oxide layer effectively increases the amount of hydrogen atoms adsorbed. Also, the hydrogen effects are found on both the Schottky barrier height lowering and the modulation in the electric field at the Pt-oxide and Pt-InAlP interfaces. In chapter 3, hydrogen sensing properties of a Pt-oxide-GaN metal-oxide-semiconductor-type Schottky diode is demonstrated and studied. In the hydrogen-containing environment, the shift of current-voltage curves and decrease of turn-on voltage Von are found to be caused by the lowering of Schottky barrier height. Also, the corresponding series resistance Rs is decreased from 191.8 (in air) to 155.3 Ω (under a 9970 ppm H2/air gas) at 30oC. As the carrier gas is replaced by a nitrogen gas, a significant variation of 0.32 V and 19.56 Ω in Von and Rs values are obtained at 30oC, respectively, even at an extremely low hydrogen concentration of 4.3 ppm H2/N2. Since the oxygen atoms will be dissolved on the Pt metal surface and react with hydrogen atoms by the formation of hydroxyl and water, the amount of adsorbed hydrogen atoms on the Pt surface is reduced. Moreover, the shorter response time constant and the larger initial rate of current density variation are found even at room temperature. In chapter 4, an interesting transistor-type hydrogen sensing detector based on GaAs pseudomorphic high electron mobility transistor with a Pd/Al0.24Ga0.76As metal-semiconductor Schottky gate structure is fabricated and investigated. The significant modulations in electrical signals are observed obviously due to the adsorption of hydrogen atoms at Pd-semiconductor interface. The corresponding adsorption and desorption time constants (�跾 and �踀) are 2.5 and 6 sec, respectively, under a 9970 ppm H2/air gas at 160oC. Theoretically, the dipolar layer formed by the hydrogen atoms adsorbed at the Pd-AlGaAs interface can be considered as a two-dimensional layer. The simulated curves show excellent agreement with experimental results. In addition, an anomalous decrease phenomenon in transient response is observed, which may be caused by the formation of hydroxyl species and water. Consequentially, the studied device provides the promise for GaAs integrated circuit and micro electric and mechanic system applications. In chapter 5, the interesting hydrogen sensing characteristics of two transistors with an Al0.24Ga0.76As (device A) and In0.49Ga0.51P (device B) Schottky layer are demonstrated. Experimentally, device A shows a lower hydrogen detection limit of 4.3 ppm H2/air, a higher current variation of 7.79 mA and a shorter adsorption time of 10.95 s in a 9970 ppm H2/air at room temperature. On the other hand, device B exhibits more stable hydrogen-sensing characteristics at high temperatures. In addition, the transient hydrogen sensing phenomenon of device A is studied. In an N2 environment, the sensing signal is proportion to the logarithmic values of hydrogen concentration at temperature from 30 to 160oC. Due to the higher activation energy for initiating the reverse hydrogen release process, the current-response of hydrogen-detecting signal is always not recovered back to the original baseline level. At higher temperature, the recovering curve can be divided into three regions: (i) initial, (ii) accumulation, and (iii) revival stages. Because the recombination process of hydrogen atoms is slower, larger amount of desorbed hydrogen atoms are accumulated on the Pd metal surface which results in the longer desorption time. However, the higher speed desorption phenomenon is observed in the presence of oxygen. In chapter 6, a back-end amplifying integrated circuit is designed and fabricated. The output amplifying circuit is composed of three electronic devices including the decoder, CMOS transmission gate switch, and operational amplifier. Several input sensing signals can be introduced simultaneously and controlled by the decoder and switch. One of these input sensing signals can pass through the switch, and the output signal of the sensing signal is amplified.