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Calibration and Characterization of Low-Cost Fine Particulate Monitors and their Effect on Individual EmpowermentTaylor, Michael D. 01 December 2016 (has links)
Air quality has long been a major health concern for citizens around the world, and increased levels of exposure to fine particulate matter (PM2:5) has been definitively linked to serious health effects such as cardiovascular disease, respiratory illness, and increased mortality. PM2:5 is one of six attainment criteria pollutants used by the EPA, and is similarly regulated by many other governments worldwide. Unfortunately, the high cost and complexity of most current PM2:5 monitors results in a lack of detailed spatial and temporal resolution, which means that concerned individuals have little insight into their personal exposure levels. This is especially true regarding hyper-local variations and short-term pollution events associated with industrial activity, heavy fossil fuel use, or indoor activity such as cooking. Advances in sensor miniaturization, decreased fabrication costs, and rapidly expanding data connectivity have encouraged the development of small, inexpensive devices capable of estimating PM2:5 concentrations. This new class of sensors opens up new possibilities for personal exposure monitoring. It also creates new challenges related to calibrating and characterizing inexpensively manufactured sensors to provide the level of precision and accuracy needed to yield actionable information without significantly increasing device cost. This thesis addresses the following two primary questions: 1. Can an inexpensive air quality monitor based on mass-manufactured dust sensors be calibrated efficiently in order to achieve inter-device agreement in addition to agreement with professional and federally-endorsed particle monitors? 2. Can an inexpensive air quality monitor increase the confidence and capacity of individuals to understand and control their indoor air quality? In the following thesis, we describe the development of the Speck fine particulate monitor. The Speck processes data from a low-cost dust sensor using a Kalman filter with a piecewise sensing model. We have optimized the parameters for the algorithm through short-term co-location tests with professional HHPC-6 particle counters, and verified typical correlations between the Speck and HHPC-6 units of r2 > 0:90. To account for variations in sensitivity, we have developed a calibration procedure whereby fine particles are aerosolized within an open room or closed calibration chamber. This allows us to produce Specks for commercial distribution as well as the experiments presented herein. Drawing from previous pilot studies, we have distributed low-cost monitors through local library systems and community groups. Pre-deployment and post-deployment surveys characterize user perception of personal exposure and the effect of a low-cost fine particulate monitor on empowerment.
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Characterization of Single Photon Avalanche Diodes Using a Black Body SourceSkender, Alexander J. 12 August 2022 (has links)
No description available.
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Automated High-Temperature Pressure Sensor Verification and CharacterizationBartkevicius, Algirdas January 2023 (has links)
Gas turbines are widely used in power generation. Monitoring pressure variations in the combustion chamber allows for real-time assessment of the turbines performance, and can be used to optimize combustion processes, leading to reduced emissions. By analyzing pressure, patterns, potential faults or degradation in critical components can be identified, enhancing the safety and reliability of the gas turbine. Measurements close to the combustion flame put high demands on the pressure sensors and their verification method. The aim of this thesis is thus to create an automated pressure sensor verification prototype capable of operating at elevated temperature. With the intention of increasing knowledge of how high temperature influences piezoelectric dynamic pressure sensor readings, this thesis inherits and updates an existing pressure sensor verification device. A design of thermal management system for the device is presented together with a CFD model analysis for the cooling cycle, while the heating cycle and its control algorithm is studied experimentally. This thesis also focuses on sinusoidal pressure wave generation methods used in the existing verification device to achieve reliable signals at low frequencies. An experimental study to evaluate the signal quality is performed. The results propose a feasible prototype design for automated pressure sensor verification at elevated temperature. It provides insight on how the separate parts of the thermal management system could be implemented with a PID regulator. It is concluded that air heating, even with to some extent varying mass flow, can be controlled with a PID regulator. It is also concluded that stable sinusoidal pressure waves can be generated at as low as 1Hz with the gear wheel method used in the previous verification device.
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Development of monolithic active pixel sensors for radiation imagingCorradino, Thomas 08 March 2024 (has links)
The development of Fully Depleted Monolithic Active Pixel Sensors (FD-MAPS) represents nowadays a hot-topic in the
radiation detector community. The advantages in terms of production costs and easiness of manufacturing in comparison to the state-of-the-art hybrid detectors boost the research effort in the direction of developing new CMOS compatible detector technologies. To this end, the INFN ARCADIA project targeted the design of a sensor platform for the production of FD-MAPS to be employed in different scientific, medical and space applications. The sensor technology has been developed in collaboration with LFoundry on the basis of a standard 110nm CMOS production process with some modifications needed to meet the project requirements. High resistivity n-type silicon substrates have been chosen for the sensor active volume and a n-type epitaxial layer has been included at the sensor frontside to delay the onset of the punch-through current flowing between the frontside and backside p-type implants. The sensor n-type collection electrodes are surrounded by pwells, which can host the embedded analog and digital frontend electronics, and deep pwells have been included below the pwells to shield them from the sensor substrate. Three engineering runs have been submitted and the produced wafers have been delivered in 2021, 2022 and 2023, respectively. An additional p-type implant has been added in the third production run to create an embedded gain layer below the n-type collection electrodes, to enhance the signal through avalanche multiplication. A selection of the main results obtained from the TCAD simulations and of the most relevant measurements performed on the designed MAPS passive test structures will be presented and discussed in chapter 4. In an analogous way, the experimental
results obtained from the characterization of an active sensor designed for brachytherapy, called COBRA, are reported
in chapter 5. The calibration of the capacitance included in the internal charge injection circuit of two TJ-Monopix2
MAPS having different substrate types is reported in chapter 6. These sensors represent examples of fully functional and
full scale monolithic prototypes realized in a 180nm Tower-Jazz CMOS process, that have been characterized using X-rays fluorescence techniques at the SiLab of the University of Bonn. Finally, in the Conclusions section the main results of the research activity are summarized and the possible future spin-offs of the project are presented.
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Modelagem cinemática e dinâmica de uma mão robótica para aplicações práticas de teleoperaçãoZucatelli, Fernando Henrique Gomes January 2017 (has links)
Orientador: Prof. Dr. Magno Enrique Mendoza Meza / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Mecânica, 2017. / Este trabalho apresenta (i) a implementação de uma mão robótica humana produzida por impressora 3D com a caracterização de sensores
flexíveis e de força e os respectivos
algoritmos de operação; (ii) a modelagem cinemática e desenvolvimento de seu simulador; (iii) a modelagem dinâmica e seu respectivo simulador e (iv) simulações numéricas da
dinâmica de contato entre a ponta do dedo da mão e um objeto. A aplicação da tecnologia de impressão 3D é crescente na medicina. Para criar proteses mais naturais adiciona-se o
conhecimento de outras areas como robotica e sistemas de controle. Os sensores
flexíveis sao necessarios para adquirir o sinal de referência para o posicionamento dos dedos por
meio de uma luva na qual estes sensores encontram-se fixados. Os de forca sao usados para controlar a m~o com base na forca que se deseja aplicar ao segurar um objeto, seu comportamento foi estudado e a curva de cada sensor obtido experimentalmente. O microcontrolador Arduino® é responsavel pela aquisição de dados dos sensores e pelo
acionamento dos servomotores que movimentam os dedos. A modelagem cinematica da mao robotica foi realizada com base na convenção de Denavit-Hartenberg e a modelagem
dinamica com uso das equações de Euler-Lagrange a partir das funções de energia. Os simuladores foram criados com uso de Matlab/Simulink®, os quais permitem verificar
os modelos cinematico e dinamico obtidos, todavia, dada a complexidade matematica envolvida na modelagem foi criado um programa para realizar os passos matematicos;
fornecer o codigo para os simuladores criados; e um breve relatorio com as equações resultantes para rápida verficação, ou com os resultados das simulções numericas. O
modelo com restriçãoo ao movimento é obtido adicionando multiplicadores de Lagrange à função Lagrangiana de energia de acordo com as equações de restrição ao movimento,
esses multiplicadores fornecem a força de contato. O instante da colisão é modelado para a correta execução da dinâmica dos corpos acoplados. Dois modelos foram obtidos (i) um
modelo simplificado que conserva o momento linear entre a a ultima articulaçõa e a barreira e que atualiza as velocidades das outras articulações como uma fração das velocidades
que antecedem o impacto; (ii) um modelo completo, o qual considera-se todos os torques e distancias envolvidas para a atualização das velocidades. Os resultados mostraram
que o modelo simplificado é capaz de obter resultados proximos do modelo completo dependendo do ajuste do parametro que define a fração de velocidades. Testes utilizando
uma simplificação das não linearidades para angulos e velocidades pequenos se mostraram satisfatorios somente quando o sistema nao entrar em contato com a barreira. / This works presents (i) the implementation of a robotic hand made by a 3D-Printer with the characterization of
flexible and force sensors and the respective algorithms of
operation, (ii) the kinematic modeling and its simulator development, (iii) the dynamic modeling and its respective simulator and (iv) numerical simulations of contacts dynamics
between the fingertip of the hand with an object. Applications of this technology are increasing worldwide in medicine. To create more natural prostheses it is added knowledge
from other areas such as robotics and control systems. Flexible sensors are needed to acquire the reference signal to move each finger from a glove in which these sensors are
assembled. Force sensors are used to control the hand reading the applied force when it is desired to hold an object. The microcontroller Arduino® is responsible for acquiring
data from the sensors and actuation of servomotors that move the fingers. Kinematic modeling of the prosthesis was based on Denavit-Hartenberg convention and dynamic modeling with use of the Euler-Lagrange from energy functions. The simulators were created with use of Matlab/Simulink®, they allow to verify the kinematic and dynamic models obtained, however, given the mathematical complexity involved in modeling, it was created a program to perform mathematical steps; to provide the code to simulator's blocks; and a short report with the resulting equations for simple checking, or with simulations results. The move constrained model is obtained adding Lagrange multipliers to the Lagrangian energy function accordingly to the restriction equations, these multipliers provide the contact force. The collision instant is modeled to the correct execution of the coupled bodies dynamics. Two models was made (i) one simplifoed model holding only the linear momentum conservation between the last articulation and the barrier,which updates other velocities as a fraction of the velocity before impact; (ii) one complete model, that evaluates every torque and distance of the bodies to update each velocities.
The results show the simplified model is able to achieve similar results of the complete model depending of the adjustment of the parameter that denes the fraction of velocities.
Some tests with a simplification of nonlinearities for small angles and velocities was made, although results were only satisfactory when no contact happens.
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Sensorkaraktärisering kring delamineringPaul, Sanjib January 2020 (has links)
Dagens industrier håller på att bli allt mer automatiserade, smartare och effektivare, i samband med detta ökas kraven att man tar fram noggrannare och pålitligare sensorsystem som är även kostnadseffektiva. Målet med denna undersökning har varit tillsammans med Iggesund Pappersbruk är att karakterisera noggrannheten för sensorn Ultrasonic Double sheet moniter (DSM) och även ta fram riktlinjer för en ingående inline mätande prototyp. Studien använder sig av väldigt enkla metoder för att karakterisera resolutionen och även undersöka det minimala avståndet för flera seriekopplade sensorer utan att de ingriper och stör varandras inläsningar. De programvaror som används under studien är PACTware och Matlab. Undersökningen visar resultat på en trovärdig noggrannhet utav sensorn och man har även kunnat karakteriserat detektions arean runt om receivern för den framtida prototypen. Avslutningsvis går studien igenom synpunkter på DSM sensorn och en diskussion om att karakterisa olika destruktiva ytor men även om vad som kan förbättras eller förbyggas. / Today's industries are becoming more automated, smarter and more efficient, and it requires high standards to develop more accurate and reliable sensor systems that are low-cost. The aim of this study was together with Iggesund Pappersbruk to characterize the accuracy of the Ultrasonic Double Sheet Monitor (DSM) sensor and to develop guidelines for an in-line measuring prototype. The study uses quite simple methods to characterize the resolution and investigate the minimum distance for several series-connected sensors without interfering with each other's readings. The software used during the study is PACTware and Matlab. The study shows results on a credible accuracy of the sensor and it has also been possible to characterize the detection area around the emitter for the future prototype. Finally, the study concludes with views on the DSM sensor and a discussion on how to characterize different destructive surfaces but also what can be improved or prevented.
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