Dissertations / Theses on the topic 'BTX sensors'

The European emission standard is an EU directive which describes what emission limits car manufactures are required to meet. In order to meet these requirements car manufacturers use different techniques and components. In a modern diesel automobile a Diesel Particulate Filter (DPF) is used to gather soot from the exhausts. As soot accumulates in the DPF, the back pressure increases and the capability to hold more soot decreases. Therefore the DPF continuously needs to get rid of the stored soot. The soot is removed through a process called regeneration. In order to optimize when to perform regeneration, it is vital to know the amount of soot in the filter. A method for estimating the soot mass in a DPF using a radio frequency-based sensor has been developed. The sensor that has been studied is the Accusolve soot sensor from General Electric. A parameter study has been performed to evaluate the parameters that affects the sensor’s output. Parameters that have been studied include positioning of the sensor, temperature in the DPF, flow rate through the DPF and distribution of soot in the DPF. Different models for estimation of soot mass in the DPF has been developed and analyzed. An uncertainty caused by removing the coaxial cable connectors when weighing the DPF has been identified and methods for minimizing this uncertainty has been presented. Results show that the sensor output is sensitive to temperature, soot distribution and position, and also show some sensitivity to the flow rate. An ARX model, with only one state, is proposed to estimate the soot mass in the DPF, since it gives the best prediction of soot mass and showed good resistance to bias errors and noise in all the input signals.

La qualité de l’air extérieur (QAE) a fait l’objet d’une législation dès 1996 avec la loi LAURE. Depuis 2008, la directive européenne 2008/50/CE a instauré des obligations de mesure et de seuils à ne pas dépasser pour certains polluants à l’échelle européenne. Selon de nombreuses données toxicologiques et épidémiologiques, la pollution de l’air est à l’origine d’insuffisances respiratoires, d’asthme, de maladies cardiovasculaires et de cancers.Les composés organiques volatils (COV) et notamment le benzène, le toluène, l’ethylbenzène et les xylènes (les composés BTEX) sont des polluants avérés et participent grandement à la dégradation de la qualité de l’air intérieur et extérieur. Ce travail de thèse a concerné la réalisation d’un multicapteur de gaz à base d’oxyde métallique pour la détection de traces de BTEX dans le cadre du projet SMARTY (SMart AiR qualiTY). Un système de caractérisation électrique complet a été conçu et mise au point pour la détection de très faibles concentrations de BTEX (le ppb). Après une étude bibliographique, plusieurs matériaux ont été sélectionnés (WO3, ZnO, SnO2). Les caractérisations électriques des couches sensibles sélectionnées ont été effectuées sous air sec et sous différents taux d’humidité en présence de BTEX et de gaz interférents (NO2, CO2). Le WO3 a montré les meilleures performances en présence d’humidité et a été choisi pour le transfert de technologie qui accompagne les nouveaux transducteurs brevetés AMU. Le multicapteur à base de WO3 a montré une détection limite de 1 ppb sous 50% d’humidité relative et a permis de détecter et de quantifier de manière efficace les BTEX
Outdoor air quality is subjected to the law LAURE since 1996. In 2008, the european directive 2008/50/EC introduced measurement requirements and thresholds that should not be exceeded for certain pollutants on a european scale. According to several toxicological and epidemiological studies, air pollution causes respiratory failure, asthma, cardiovascular diseases and cancers. In Europe, air pollution is responsible for more than 300 000 early deaths a year.Volatile organic compounds (VOCs), particularly benzene, toluene, ethylbenzene and xylenes (BTEX compounds) are proven pollutants and play a major role in the degradation of indoor and outdoor air quality. This thesis is dedicated to the development of a metal oxide based multi-gas sensor for the detection of traces of BTEX within the framework of the SMARTY project (SMart AiR qualiTY). A complete electrical characterization system was designed and implemented for the detection of sub-ppm concentrations of BTEX.Based on the state-of-art, several materials were selected (WO3, ZnO, SnO2). The electrical characterizations of the selected sensitive layers were carried out under dry air and under different humidity levels in the presence of BTEX and interfering gases (NO2, CO2). Tungsten oxide (WO3) exhibits the best performance in the presence of moisture and is chosen for the technology transfer that accompanies the new patented AMU transducers. The WO3-based multi-sensor has a lower limit of detection (LOD) of 1 ppb at 50% relative humidity and effectively detects and quantifies BTEX

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A contaminação de águas subterrâneas e superficiais com poluentes orgânicos, como os hidrocarbonetos presentes nos derivados de petróleo, causa um perigo potencial à saúde das populações, tornando-se necessário à avaliação contínua dos níveis de concentração destas substâncias. Para isso, é importante o desenvolvimento de técnicas analíticas de baixo custo para o monitoramento contínuo e remoto de águas de drenagem contaminadas e para o controle de efluentes industriais. Os hidrocarbonetos aromáticos, como o benzeno, o tolueno, o etilbenzeno e os xilenos (BTEX), são os constituintes da gasolina mais solúveis em água e, assim, podem se difundir com facilidade no lençol freático. A espectroscopia na região do Infravermelho Próximo (NIR) vem sendo adotada em várias áreas, como na agricultura, nas indústrias alimentícias, farmacêuticas, químicas e petroquímicas, por ser uma técnica simples, rápida, não-destrutiva e de baixo custo. O objetivo deste trabalho foi o desenvolvimento de um sensor óptico à base de uma fase sensora de silicona acoplada a um espectrofotômetro NIR (Infravermelho Próximo) para a determinação de BTEX em amostras aquosas. Inicialmente foram avaliados diferentes tipos de silicona com características apropriadas para construção do sensor, como transparência e plasticidade, tendo-se selecionado a silicona à base de Polidimetilsiloxano (PDMS). Um estudo dinâmico foi efetuado para avaliação do tempo de resposta da sonda para cada constituinte dos BTEX, adotando-se a resposta da sonda como sendo de um sistema de primeira ordem. Com este estudo, comprovou-se que o sistema tem um comportamento de primeira ordem, tornando válido o modelo proposto para a difusão de hidrocarbonetos aromáticos em silicona à base de PDMS. Os tempos de resposta para o benzeno, tolueno, etilbenzeno e m-xileno foram de 0,48 h, 1,34 h, 2,00 h e 1,97 h, respectivamente. Realizando-se uma análise por componentes principais dos dados espectrais obtidos para cada composto individualmente, misturas contendo BTEX e amostras contaminadas por gasolina e diesel, verificou-se que é possível distinguir se uma amostra aquosa tem um dos aromáticos em estudo e se a mesma foi contaminada por gasolina ou óleo diesel. Diante disso, pode-se concluir que o sistema sensor-NIR pode ser utilizado para determinação qualitativa de hidrocarbonetos aromáticos em águas superficiais e subterrâneas

This thesis describes the design and implementation of a system for checking the boxes completeness. Thesis is divided into several parts. The first part includes an introduction into the manufacturing process and also devices, for which the system is designed. The second part consists of system design and a description of hardware components used for the system. The third part deals with the creation of a scheme used for connection an electrical switchboard. The fourth part is focused on a design of mechanical constructions, such as construction plan used for vision sensors connection, lighting system and design mechanical parts of stopper. A simulator of the system for checking the boxes completeness is described in the fifth part. It is used for a demonstration of functionality and controllability of the system. The sixth part deals with enabling of a communication between particular sub-systems, such as vision sensors, control panel and control system. The seventh part is focused on creation of the software required for the control system, HMI panel and deals with the configuration of pair vision sensors. In the final part there are some illustrations of designed system in real process of manufacturing.

The report deals with the study of the resistence of the nonporous polymer materiále against permeation of the selected TICs, with the analysis of the running difussion processes and utilization of the acquired results for the selection of suitable barrier materials for the protective means.

En los últimos años, el uso de la tecnología en deportes se ha multiplicado. La inteligencia artificial, y el procesamiento de imágenes y datos a gran escala son algunos de los avances más resaltantes. Gracias a estas tecnologías, muchos productos han surgido para deportistas de élite. Los atletas las usan para evaluar su rendimiento y mantener un reporte de todos sus entrenamientos. A pesar de esta explosión de tecnologías, el box, siendo un deporte con abundantes aficionados, cuenta con escasas investigaciones en sistemas de entrenamiento. En esta investigación se explorará y se analizarán las diferentes técnicas de detección de movimiento en deportes. Así mismo, se identificarán las arquitecturas de estos sistemas y se propondrá oportunidades de mejora. Finalmente, revisaremos las aplicaciones más recientes de box para comparar sus funcionalidades.
In the past few years, technology used in sports has multiplied. Artificial intelligence, image and data processing at large scale are some of the most notable advancements. These technologies have allowed for several new products to flood the elite athlete market. These athletes use them to gage their performance and to keep a record of all their training sessions. Despite this new renaissance, and despite having a huge fanbase, boxing still has little research on training systems. In this investigation, various movement detection techniques will be explored and analyzed. Then, the architecture of these systems will be identified, and improvements will be suggested. Finally, we will review and compare the latest applications for boxing training.
Trabajo de investigación

Les travaux de recherche de cette thèse s'inscrivent dans le cadre de la sécurité par chaos des réseaux locaux sans fil, en particulier les réseaux de capteurs sans fil. L'originalité de cette thèse consiste à proposer des cryptosystèmes à base de chaos plus adaptés aux réseaux de capteurs, en termes de consommation d'énergie, que les algorithmes conventionnels et à réaliser une implémentation sur une plateforme réelle. Nous présentons en premier lieu un état de l'art des réseaux, les menaces, les contraintes limitant le processus de sécurité des informations ainsi que les principales techniques de cryptographie. Nous donnons un aperçu sur la théorie de chaos et nous validons l'aspect aléatoire de plusieurs suites chaotiques par les tests statistiques du NIST. Nous proposons ensuite des nouvelles méthodes de construction de S-Box chaotiques tout en prouvant leur robustesse contre les attaques traditionnelles. Nous proposons enfin un nouvel algorithme de cryptage d'image dédié au réseau de capteurs sans fil. La validation de nos contributions est effectuée par simulation et par des mesures expérimentales sur une plateforme de réseaux de capteurs réels (SensLab).

This thesis is part of the wearable electronic field, and in particular of the Organic BioElecteonic Sensors that have the in-situ real-time monitoring of the health and performance status of the subject as the main goals. With this purpose, textile-based wearable sensors for continuous and simultaneous detection of [Cl–] and pH level have been developed. PEDOT:PSS is the intrinsic conductive polymer used to make the commercial yarns conductive. The coated threads have been functionalized with Ag/AgCl NPs and BTB to make them able to detect [Cl–] and pH level, respectively. The developed sensors end up to be easy-to-make, reproducible with excellent sensitivity and stability both in single and multiple configurations without any interference. The results achieved in this work allow future improvements to develop a new textile-based device that can be easily integrated into clothing, allowing worn it in dealy life.

Clinical trials are experiments or observations on a patient’s responses of different medical treatments to cure diseases. Such trials are heavily regulated and must achieve a certain quality standard of the trial and clinical adherence is a determining factor on the success of a study. However, it has historically been difficult to systematically follow and understand patient adherence to medical ordinations, predominately due to lack of proper tools. One new type of tools is a digital pillbox that can be used to supply pills to participants in clinical trials. This paper examines implementing two supervised machine learning models to detect if an object (a pill) is found in an encapsulated compartment (pillbox) based on electromagnetic radiation data from a proximity sensor. Support Vector Machine (SVM) and Random Forest (RF) were evaluated on a data set of N=1,485 observations, consisting of five classes: four different pills and ‘no pill’. RF performs best with accuracy of 98.0% and weighted average precision of 98.0%. SVM had 97.3% accuracy and 97.6% weighted average precision. Best performance was achieved at N=1,000 for RF and 1,100 for SVM. The conclusion was that a high accuracy and precision can be achieved using either RF or SVM. The classification model strengthens the value proposition of a digital pillbox and can improve clinical trials to achieve better data quality. However, for the model to contribute actual economical value, digital pillboxes must be a common practice in clinical trials.
Kliniska studier är experiment eller observationer av en patients reaktion på olika typer av medicinsk vård för behandling sjukdomar. Sådana studier är tungt reglerade och behöver uppnå en viss kvalitésstandard och klinisk följsamhet är en avgörande faktor för en studies framgång. Trots det har det historiskt varit svårt att systematiskt mäta och förstå en patients följsamhet av en medicinsk ordination, primärt på grund av brist av användbara verktyg. En ny typ av verktyg är en digital  pillerbox som försörjer piller till deltagare i kliniska studier. Denna studie undersöker implementation av två bevakade maskininlärningsmodeller för detektion om ett objekt (ett piller) befinner sig i ett slutet fack baserad på elektromagnetisk strålning från en närhetssensor. Support Vector Machine (SVM) och Random Forest (RF) utvärderades på ett dataset av N=1 485 observationer utgjort av fem klasser: fyra piller och ’inget piller’. RF presterar bäst med 98,0% i träffsäkerhet och 98,0% i viktad medelprecision. SVM fick 97,3% träffsäkerhet och 97,6% viktad medelprecision. Bäst prestation uppnåddes vid N=1 000 för RF och N=1 100 för SVM. Slutsatsen var att en hög träffsäkerhet och precision kan uppnås genom antingen RF eller SVM. Klassificeringsmodellen förstärker en digital pillerbox värdeerbjudande och kan hjälpa kliniska studier att uppnå högre datakvalité. Däremot, för klassificeringsmodellen ska bidra med faktiskt ekonomiskt värde, behöver digitala pillerboxar vara en vedertagen praxis.

In my master's tehsis I'm dealin with the methods used for non-invasive blood pressure measurement. For realization of a virtual blood pressure meter in LabVEW I have chosen the oscillometric method. Algorithm determining systolic and diastolic blood pressure is based on the relatively easy detection of maximum amplitude oscillations (corresponds with a mean arterial pressure), when thelimiting valuesof blood pressure are in a specific ratio with a maximum amplitude of oscillation. In LabVIEW was solved loading of signal from the measure card and processing pressure curve into a form suitable for the detection of the peak oscillations. The program calculates the limits of arterial pressure and mean heart rate too. Linking the virtual device with the blood pressure sensor Vernier BPS-BTA then makes up komplex for capturing the blood pressure via oscillatory method.

The advent of deep submicron technology coupled with ever increasing demands from the customer for more functionality on a compact silicon real estate has led to a proliferation of highly complex integrated RF system-on-chip (SoC) and system-on-insulator (SoI) solutions. The use of scaled CMOS technologies for high frequency wireless applications is posing daunting technological challenges both in design and manufacturing test. To ensure market success, manufacturers need to ensure the quality of these advanced RF devices by subjecting them to a conventional set of production test routines that are both time consuming and expensive. Typically the devices are tested for parametric specifications such as gain, linearity metrics, quadrature mismatches, phase noise, noise figure (NF) and end-to-end system level specifications such as EVM (error vector magnitude), BER (bit-error-rate) etc. Due to the reduced visibility imposed by high levels of integration, testing for parametric specifications are becoming more and more complex. To offset the yield loss resulting from process variability effects and reliability issues in RF circuits, the use of self-healing/self-tuning mechanisms will be imperative. Such self-healing is typically implemented as a test/self-test and self-tune procedure and is applied post-manufacture. To enable this, simple test routines that can accurately diagnose complex performance parameters of the RF circuits need to be developed first. After diagnosing the performance of a complex RF system appropriate compensation techniques need to be developed to increase or restore the system performance. Moreover, the test, diagnosis and compensation approach should be low-cost with minimal hardware and software overhead to ensure that the final product is economically viable for the manufacturer. The main components of the thesis are as follows: 1) Low-cost specification testing of advanced radio frequency front-ends: Methodologies are developed to address the issue of test cost and test time associated with conventional production testing of advanced RF front-ends. The developed methodologies are amenable for performing self healing of RF SoCs. Test generation algorithms are developed to perform alternate test stimulus generation that includes the artifacts of test signal path such as response capture accuracy, load-board DfT etc. A novel cross loop-back methodology is developed to perform low cost system level specification testing of multi-band RF transceivers. A novel low-cost EVM testing approach is developed for production testing of wireless 802.11 OFDM front-ends. A signal transformation based model extraction technique is developed to compute multiple RF system level specifications of wireless front-ends from a single data capture. The developed techniques are low-cost and facilitate a reduction in the overall contribution of test cost towards the manufacturing cost of advanced wireless products. 2)Analog tuning methodologies for compensating wireless RF front ends: Methodologies for performing low-cost self tuning of multiple impairments of wireless RF devices are developed. This research considers for the first time, multiple analog tuning parameters of a complete RF transceiver system (transmitter and receiver) for tuning purposes. The developed techniques are demonstrated on hardware components and behavioral models to improve the overall yield of integrated RF SoCs.

Die Geräte, durch die Musik im Zeitalter der technischen (Re-)Produktion gehört wird, haben sich immer wieder gewandelt. Solche Geräte müssen überhört werden. Nur so kann Musik gehört werden. Trotzdem – so die These der Arbeit – organisieren diese Geräte das Hören und sind Agenturen einer Bewirtschaftung und Technisierung der Wahrnehmung. In der Arbeit wird anhand von zwei Fallstudien aus der Geschichte der Rock- und Popmusik gezeigt, wie solche Geräte sowohl den Hörer als auch die gehörte Musik formieren. Durch Hörtechnologien bilden sich neue Hörpraktiken heraus und die Körperlichkeit des Hörers wird neu bestimmt. Die Anpassung von Klanggeschehen an spezifische Hörtechnologien wird im Mastering – dem letzten Schritt der technischen Musikproduktion – untersuchbar. Die Geräte, durch die Musik gehört wird, sind also weder schlichte Wiedergabetechnologien noch bloße elektrotechnische Artefakte. Vielmehr sind sie Gefüge aus Klanglichkeit, Körperlichkeit und Technologie. Diese werden in der Arbeit als Hörgeräte auf den Begriff gebracht. Die Hörgeräte der Rock- und Popmusik zielen – wie ihre medizintechnischen Verwandten – auf die Materialität der Wahrnehmung. Im Gegensatz zu diesen funktionieren sie jedoch nicht als Prothesen, die an einer gattungsweit postulierten Norm ausgerichtet sind. Statt Normen bergen sie Exzesse – an Serialität und Wiederholung – sowie Eskalationen – von Lautstärke und von hohen und tiefen Frequenzen. Die Arbeit ist in drei Kapiteln gegliedert. Im ersten Kapitel wird die These der Arbeit in Bezug auf theoretische Diskurse der Musik-, Kultur- und Medienwissenschaft verortet und eine begriffliche Systematik entwickelt. Kapitel zwei und drei sind Fallstudien gewidmet. In der ersten wird das Jukeboxhören der Rock’n’Roll-Kultur der 1950er Jahre untersucht, in der zweiten das Soundsystemhören der Disco- und Clubkultur der 1970er bis 1990er Jahre. Die im ersten Kapitel entwickelte begriffliche Systematik macht die Fallstudien vergleichbar.
The devices by which music is listened to in the age of technological (re-)production have changed over and over again. These devices must be imperceptible to the ear. Only then can music be heard. Nonetheless – this is the claim of the thesis – these devices organize hearing and are agents of a cultivation and technization of perception. Based on two case studies from the history of rock and pop music, this thesis reveals how such devices constitute not only the listener but also the music which is listened to. Through listening technologies new listening practices emerge and the corporality of the listener is newly defined. The adaptation of sound to specific listening technologies can be analysed during the mastering process, the last step in technological music production. The devices by which music is listened to are thus neither simple technologies of reproduction nor mere electrotechnical artefacts. Rather, they are assemblages of sound, corporality, and technology. In this thesis these assemblages are called “Hörgeräte” (listening devices). The listening devices of rock and pop music target – like medical-technical “Hörgeräte” (hearing aids) – the materiality of perception. Contrary to medical technologies, however, listening devices do not function as prostheses, which are calibrated according to medical industry standards. Instead, they contain excesses – of seriality and repetition – and escalations – of amplitude and high and low frequencies. The thesis is arranged in three chapters. In the first chapter I situate the main argument of the thesis within discourses of musicology, media and cultural studies, and develop my own terminology. Chapters two and three deal with case studies. In chapter two I investigate jukebox listening in 1950s rock’n’roll culture, whilst in chapter three I explore sound system listening in disco and club culture from the 1970s to the 1990s. The terminology developed in chapter one enables a comparison of the case studies.

Dissertação de Mestrado Integrado em Engenharia Física apresentada à Faculdade de Ciências e Tecnologia
Esta dissertação teve como intuito o desenvolvimento de uma unidade multissensorial para a monitorização remota de transformadores de distribuição em redes elétricas, tendo em vista o suporte à sua manutenção prescritiva. Esta unidade visa promover, simultaneamente, o prolongamento do tempo de vida útil destes equipamentos e a melhoria da qualidade do serviço prestado.As variáveis relevantes e os eventos de interesse na caracterização do estado de funcionamento dos transformadores são assim apresentados, bem como as metodologias e tecnologias usadas no dispositivo desenvolvido para a sua monitorização.Os fatores mais importantes e distintos deste dispositivo são o seu carácter não intrusivo e a sua total ausência de cablagem, quer de comunicação, quer de alimentação em potência. Assim, para a alimentação, optou-se por um sistema de captação de energia do diferencial térmico permanente entre o transformador e o ar envolvente. Deste modo, foram realizados testes para a seleção e validação dos módulos termoelétricos mais adequados.Quanto à comunicação, é devidamente justificada a opção pela tecnologia Bluetooth Low Energy, suportada num módulo integrado de comunicação e processamento.O sistema encontra-se, neste momento, em fase de prototipagem industrial, assim permitindo a realização de uma bateria de testes finais em condições reais. Estes terão lugar em laboratórios altamente diferenciados, em instituições académicas e industriais.Palavras-Chave: IIoT, Sensor Inteligente, Captação de Energia, Transformadores de Distribuição, Redes Elétricas Inteligentes, Diagnóstico Automático
The primary objective of the present work consists in the design and development of a smart multi-sensor for the remote monitoring of distribution transformers in power grids, in view of supporting their prescriptive maintenance. This sensor simultaneously promotes the extension of the equipment’s life span and the improvement in the respective quality of the service.The relevant variables and the events of interest to the characterization of the transformers’ operating status are presented, as well as the methods and technologies used for the device operation.This device’s most important and distinctive features are their non-intrusive and wireless character, requiring neither communication nor power supply cabling. Thus, in what regards the power unit, the option consists of energy harvesting from the permanent temperature differential between a transformer and the surrounding air. Accordingly, tests were carried out in order to select and validate the most appropriate thermoelectric modules.Concerning communication, an option for Bluetooth Low Energy is discussed, which is duly supported by an integrated module encompassing both communication and processing capabilities.The system is, at the present time, in a stage of industrial prototyping, thus allowing a final testbed to be carried out in realistic conditions. This will take place both in industrial and academic institutions.Keywords: IIoT, Smart Sensors, Energy Harvesting, Distribution Transformers, Smart Grids, Automatic Diagnosis

碩士
國立臺灣科技大學
自動化及控制研究所
102
The embedded systems have low energy-consuming and long-term stable operation with relative low-cost system architecture. To miniaturize the existing robot SPA (Sense, Plan, Act) model to work in a card-size board as cost-effective micro-architecture is our application goal of sensor box. A STTA-Loop microstructure is well defined as the loop of Sense, Trigger, Transport and Actuator states, and then makes critical sensing data easily and continuously send to a cloud site possible. Our study has used Raspberry Pi system board to implement a sensor box and has made good use of Python language as development tool to carry out two case studies. A conventional waterfall model is presented by 7 major design steps, that are mostly illustrated by UML model diagrams to describe the interactive behaviors and states of system board and its attached GPIO devices. Two case studies have been used to demonstrate the I/O functions of sensor box with finger pulse data sensed on sudden cold (or hot) environment and ultrasonic wave effects on distances. The sensors can get the real floating data within the assigned temperature range, and use a buzzer and four 8x8 dot matrix modules to indicate the output status. This system would take a proper GMAIL-notification action for exceptional filtered data. Our study made a data-sent-out and store-and-browse implementation to interact with ThingSpeak cloud platform by short python code with triggering thresholds UI and simple API call .

Indiana University-Purdue University Indianapolis (IUPUI)
An Autonomous vehicle depends on the combination of latest technology or the ADAS safety features such as Adaptive cruise control (ACC), Autonomous Emergency Braking (AEB), Automatic Parking, Blind Spot Monitor, Forward Collision Warning or Avoidance (FCW or FCA), Lane Departure Warning. The current trend follows incorporation of these technologies using the Artificial neural network or Deep neural network, as an imitation of the traditionally used algorithms. Recent research in the field of deep learning and development of competent processors for autonomous or self-driving car have shown amplitude of prospect, but there are many complexities for hardware deployment because of limited resources such as memory, computational power, and energy. Deployment of several mentioned ADAS safety feature using multiple sensors and individual processors, increases the integration complexity and also results in the distribution of the system, which is very pivotal for autonomous vehicles. This thesis attempts to tackle two important adas safety feature: Forward collision Warning, and Object Detection using the machine learning and Deep Neural Networks and there deployment in the autonomous embedded platform. 1. A machine learning based approach for the forward collision warning system in an autonomous vehicle. 2. 3-D object detection using Lidar and Camera which is primarily based on Lidar Point Clouds. The proposed forward collision warning model is based on the forward facing automotive radar providing the sensed input values such as acceleration, velocity and separation distance to a classifier algorithm which on the basis of supervised learning model, alerts the driver of possible collision. Decision Tress, Linear Regression, Support Vector Machine, Stochastic Gradient Descent, and a Fully Connected Neural Network is used for the prediction purpose. The second proposed methods uses object detection architecture, which combines the 2D object detectors and a contemporary 3D deep learning techniques. For this approach, the 2D object detectors is used first, which proposes a 2D bounding box on the images or video frames. Additionally a 3D object detection technique is used where the point clouds are instance segmented and based on raw point clouds density a 3D bounding box is predicted across the previously segmented objects.

This dissertation describes the research and development of a communication system to support remote control devices (RCD) for Android-based set-to-box (STB). The target RCD is a low-complexity device using 3D motion tracking to provide new interactive functionalities to di erent types of multimedia content and applications. The system architecture comprises an RCD with Magnetic, Angular Rate, Gravity (MARG) unit for 3D motion tracking, transmitting data to an Android STB. The communication between the RCD and the STB was implemented using the Radio Frequency for Consumer Electronics (RF4CE) protocol, which required the development of an external module for the STB. An Application Programming Interface (API) was developed to enable seamless computation of the remote control data and allowing six input pro- les on the Android: Absolute air mouse, Relative air mouse, multitouch, accelerometer, gyroscope and magnetometer. To allow the sensors from the MARG unit in the remote control device to be natively recognized on the Android OS, an Android sensors library was also developed, this reads the sensors data from the API. The demonstration of the system functionalities was done through an Android application speci cally developed to simulate and test a potential usage environment. A study to nd out whether the most complex functions should run on the RCD or on the Android STB was also carried out. The optimal solution still remains an open issue since it depends on the speci c application and portability requirements taking into account energy consumption. The analysis of energy consumption on the RCD shows that transmitting the raw data from the sensors to be processed in the API, results in a lower energy consumption, and consequently higher portability with good accuracy. Since the STB has no limitations on energy consumption and superior computational power, the API was designed to be able to perform all the processing of sensors data, thus allowing the implementation of complex fusion algorithms with higher precision.

碩士
國立雲林科技大學
工業化學與災害防治研究所碩士班
90
Polypyrrole(PPy) films were prepared electrochemically(PPy-ClO4) and chemically(PPyCl) to detect BTEX(benzene, toluene, ethylbenzene, and xylene) compounds in their vapor phases. Three isomers of xylene, i.e. ortho-（o-）, meta-（m-）, and para-（p-）, were also investigated for comparison. The adsorption equilibrium constants, Km, were determined according to the proposed sorption model. The measured Km for BTEX molecules adsorbed onto PPy-ClO4 and PPyCl layer showed an order in magnitude as follows： PPy-ClO4：p-xylene＞ethylbenzene＞o-xylene＞m-xylene＞toluene PPyCl ：o-xylene＞m-xylene＞p-xylene＞ethylbenzene＞toluene＞benzene A further study of affinity between the PPy film and BTEX was carried out by a method of Inverse Gas Chromatograph(IGC). From the IGC result, it was found that the measured retention volume of BTEX vapor correlated well with the values of Km. The adsorption free energy DGa, split into dispersive term, DGad, and specific interaction term, DGas, for BTEX molecules adsorbed onto PPyCl surface, was determined and was used to interpret the sensing responses. On the other hand, The surface free energies of the chemically synthesized conducting polypyrrole(PPyCl), were also measured by IGC. The dispersive component of the surface tension (γsd) of PPyCl is 74.73 mJ/m2 at 443K, showing that the PPyCl is a high-surface energy material compared with the other conventional polymers. The interaction forces were analyzed in details by a method of linear solvation energy relationships(LSER), by which the surface of the polypyrrrole was found to exhibit a basic nature.

Enterprising technologies and policies that focus on energy reduction in buildings are paramount to achieving global carbon emissions targets. Energy retrofits, building stock modelling, heating, ventilation, and air conditioning (HVAC) upgrades and demand side management all present high leverage opportunities in this regard. Advances in computing, data science and machine learning can be leveraged to enhance these methods and thus to expedite energy reduction in buildings but challenges such as lack of data, limited model generalizability and reliability and un-reproducible studies have resulted in restricted industry adoption. In this thesis, rigorous and reproducible studies are designed to evaluate the benefits and limitations of state-of-the-art machine learning and statistical techniques for high-impact applications, with an emphasis on addressing the challenges listed above. The scope of this work includes calibration of physics-based building models and supervised deep learning, both of which are used to estimate building properties from real and synthetic data. • Original grey-box methods are developed to characterize physical thermal properties (RC and RK)from real-world measurement data. • The novel application of supervised deep learning for thermal property estimation and HVAC systems identification is shown to achieve state-of-the-art performance (root mean squared error of 0.089 and 87% validation accuracy, respectively). • A rigorous empirical review is conducted to assess which types of gray and black box models are most suitable for practical application. The scope of the review is wider than previous studies, and the conclusions suggest a re-framing of research priorities for future work. • Modern interpretability techniques are used to provide unique insight into the learning behaviour of the black box methods. Overall, this body of work provides a critical appraisal of new and existing data-driven approaches for thermal property estimation in buildings. It provides valuable and novel insight into barriers to widespread adoption of these techniques and suggests pathways forward. Performance benchmarks, open-source model code and a parametrically generated, synthetic dataset are provided to support further research and to encourage industry adoption of the approaches. This lays the necessary groundwork for the accelerated adoption of data-driven models for thermal property identification in buildings.
Graduate

A dynamic white-box encryption scheme is proposed to address the fourth challenge. Short secret key are converted into large look-up tables and the tables are periodically shuffled by a shuffling mechanism which is secure against white-box attackers.

Ferroelectric ceramics are very promising materials for a variety of piezoelectric applications such as high permittivity dielectrics, piezoelectric sensors, piezoelectric/electrostrictive transducers, actuators, electro-optic devices, etc. Among the commercially viable ferroelectric ceramics, the lead-zircon ate-titivate Pb(Zr1-xTix)O3 (PZT) based ceramics have dominated the market due to their superior piezoelectric and dielectric property along with other advantages like high electromechanical coupling, ease of processing and low cost. However, the toxicity of lead based materials, and its volatility at processing temperatures is a serious health and environmental concern. Several legislations against lead-based products have been passed all over the world in order to encourage identification of alternative lead-free materials for these applications. As a consequence, there has been a remarkable surge in efforts by researchers on identifying lead-free alternatives for piezoelectric applications. A larger emphasis has been placed on perovskite based ceramics since in addition to possessing excellent properties, their relatively simple structure facilitates understanding structure-property relationships which are important for developing novel high performance materials. Na1/2Bi1/2TiO3 (NBT) and its solid solutions are one of the leading classes of perovskite ceramics, which show promising ferroelectric, piezoelectric and dielectric property thereby having the potential to replace PZT based ferroelectrics. The parent compound NBT is ferroelectric with large ferroelectric polarization (~40 C/cm2), promising piezoelectric properties with 0.08% maximum strain and longitudinal piezoelectric coefficient (d33) ~ 80 pC/N. Though NBT was discovered nearly six decades ago, a clear understanding of its structure remained elusive for a long time since different characterization techniques yielded contradicting reports on its structure and nature of phase transformation. However, rapid advances in characterization techniques in recent years have led to uncovering of new results, thereby shedding light on the true structure of NBT. X-ray and neutron diffraction studies in the past have shown that NBT exhibits rhombohedral (R3c) structure at room temperature, which undergoes a gradual transformation into tetragonal (P4bm) structure at ~230oC. However, recent characterization of both single crystal and powder of NBT using high resolution x-ray diffraction showed that the room temperature structure is not purely rhombohedral and the structure can be better modeled with a monoclinic (Cc) structure. In contrast to x-ray and neutron diffraction, electron diffraction studies have shown evidence for the presence of planar disorders, corresponding to in-phase octahedral tilts in the sample which cannot be accounted for by either R3c or Cc structure. In addition, EXAFS, x-ray and neutron total scattering studies, diffuse scattering studies, etc. have shown that the structural parameters obtained from bulk diffraction techniques are significantly different from the local structure of the material. Similar ambiguities have been observed even in NBT based solid solutions like BaTiO3, K1/2Bi1/2TiO3, etc. which show enhanced properties at the morphotropic phase boundary (MPB). A major breakthrough in understanding the structural complexity involved in NBT based solid solutions was achieved when it was found that the structure of the MPB compositions were sensitive to electric field. This led to solving the mystery behind the appearance of cubic-like phase at some of the MPB compositions where the application of electric-field resulted in the transformation of the structure into a co-existence of rhombohedral and tetragonal phases. Observation of an electric-field-induced structural transition at the MPB compositions was expected, because the MPB signifies instability in the system and even a minor external force can significantly influence the system. However, we have found that the structure of even pure NBT is significantly influenced by electric field and the framework of this thesis is based on this particularly important result. The intrinsic tendency of the electric field to affect the structure of NBT is a major factor which needs to be considered when studying similar phase transitions in the MPB compositions of NBT-substituted systems also. This was not taken into account by other research groups, and they assumed that the instability associated with the MPB was the only major factor involved in the electric-field induced transitions. A simple but highly effective strategy of grinding the electrically poled pellet into fine powder and then collecting x-ray diffraction patterns, facilitated elimination of preferred orientation in the sample. Thus, structural analysis by Rietveld refinement was possible even on the poled sample, which has not been carried out by any other groups on any ferroelectric ceramics so far. The initial part of the thesis deals with addressing the structural complexity of pure NBT, wherein the effect of electric field on the bulk structure as well as the local structure was studied in great detail. Later on, similar concepts are used to investigate BaTiO3 and K1/2Bi1/2TiO3 substituted NBT also. The first chapter of the thesis provides a brief introduction to the field of ferroelectrics, perovskite structure and their phase transition. An exposure to concepts like relaxor ferroelectrics, morphotrophic phase boundary, octahedral tilting, etc. has been provided. Then, a detailed overview of the existing literature related to the structure of NBT and its phase transition studies with temperature has been discussed. The details of the experimental procedures, characterization techniques used, and some theory behind these techniques have been provided in chapter 2. The third chapter deals with the room temperature structural characterization of pure NBT using techniques like x-ray diffraction, neutron diffraction, electron diffraction and EXAFS analysis. The results of these structural characterizations are also complemented with first-principles calculation study of the ground state structure of NBT, dielectric and ferroelectric characterization, and ageing studies. While x-ray and neutron diffraction clearly established electric-field induced structural transition from a monoclinic (Cc) to rhombohedral (R3c) structural transition, first principles calculation showed that the monoclinic phase is not stable and hence cannot be the ground state structure of NBT. Also, the possibility of the monoclinic features appearing in the x-ray diffraction solely due to micro structural effects by nano-sized domains was discussed. Comparison of electron diffraction of poled and unpoled samples of NBT showed that the in-phase tilted regions were greatly suppressed in the poled samples. Even HRTEM images showed that the unpoled samples had a very high concentration of strain heterogeneity in them, which was absent in the poled samples. This gave a direct evidence of correlation between observation of monoclinic phase and the presence of in-phase tilted regions in the unpoled samples. It was proposed that the strain caused by these in-phase tilted disorders caused distortion in the original rhombohedral lattice thereby making the structure appear monoclinic. Application of electric field causes the in-phase octahedral tilt disorders to vanish, thereby even the monoclinic features observed in the XRD also disappear. The fourth chapter discusses the consequences of poling on the high temperature phase transition behavior of NBT. We have used temperature dependent x-ray and neutron diffraction, Raman spectroscopy and EXAFS analysis whose results were correlated with the anomalies observed in temperature dependent dielectric and polarization studies. We found that the poled sample shows a sharp anomaly at the depolarization temperature (Td) in all the characterization techniques used, in contrast to a diffuse or negligible effect seen in the unpoled sample. The depolarization temperature was found to be associated with introduction of structural disorder in the sample in the form of in-phase octahedral tilts. This also gave rise to a normal to relaxor ferroelectric transition at Td, and this relaxor behavior persisted even after cooling the sample to room temperature. An intermediate cubiclike phase was observed from x-ray diffraction at around 300C wherein the rhombohedral phase vanishes and the tetragonal phase begins to appear. Even single crystal study of NBT in the past showed sudden disappearance of the domains at 300C, even though they were visible at both above and below this temperature. This effect was called isotropization, and was postulated to arise due to extremely small domains which made the system isotropic. However, our neutron diffraction pattern showed that in-phase tilted superlattice reflections persisted at this temperature which meant that the structure was not truly cubic at this temperature. Further, a neutron diffraction study at higher temperatures showed that the in-phase tilted superlattice reflections persisted even above the cubic phase transition temperature, in corroboration with similar reports from high temperature electron diffraction. Chapter five deals with the BaTiO3 substituted NBT system, which has gained tremendous interest in the last decade as a viable piezoelectric ceramic for commercial applications. Though a large number of groups have already carried out exhaustive studies on this system, most of the work concentrated mainly on the MPB compositions which showed enhanced piezoelectric properties. In this chapter, we highlight some important findings in the pre-MPB and post-MPB compositions. Using room-temperature and high temperature x-ray diffraction, we show that there exists a subtle compositional phase boundary at x = 0.03, which disappears upon poling the sample. While the monoclinic phase in pure NBT becomes cubiclike at this composition, the depolarization temperature (Td) also slightly increases up to this composition and then decreases upon further Ba substitution. Similar studies were also carried out with compositions containing slightly excess bismuth in them (0.1 mol %), whose purpose was to negate the effects of Bi-vaporization during sintering. It was found that while the compositional phase boundary remained essentially unchanged, there was a decrease in Td for all the compositions. It was also realized that the addition of excess bismuth improved the overall piezoelectric property of the system. Studies on higher compositions of Ba in the post-MPB regions further revealed two additional compositional phase boundaries. A criticality in the coercive field and spontaneous tetragonal strain was observed at x = 0.2, which was found to be associated with crossover from a long-period modulated tetragonal phase (for x < 0.2) to a no modulated tetragonal phase (for x > 0.2). Near the BT rich end (x ~ 0.7), the system exhibits a crossover from normal to a diffuse/relaxor ferroelectric transition with increasing Na1/2Bi1/2 substitution. The onset of relaxor state by Na1/2Bi1/2 substitution on the Ba-site, was shown to increase the spontaneous tetragonal strain in the system. This was because of the enhancement in the covalent character of the A-O bond by virtue of the Bi+3 6s2 lone pair effect, and it also led to a sudden increase in the tetragonal-to-cubic transition temperature. This was in contrast to other chemical modifications of BT reported in the past (like Zr, Sn, Sr, etc.) where the relaxor state is accompanied by a weakening of the ferroelectric distortion and a decrease in the critical temperature. Finally, chapter six covers the effect of electric field induced phase transition in K1/2Bi1/2TiO3 substituted NBT. Visual observation showed that while the compositions (x < 0.2) behaved similar to pure NBT, wherein the structure became purely rhombohedral upon poling, the effect of electric field was negligible in the post-MPB compositions (x > 0.2). In addition, the peaks in the annealed samples were considerably overlapping which made identifying the structural transitions at the MPB compositions difficult using Rietveld analysis. However, comparison of the FWHM of the {200}pc peaks of compositions x < 0.2 showed that the FWHM began to increase suddenly for x > 0.15 indicating emergence of the tetragonal phase. Also, all the compositions showed an increase in the {200}pc peak FWHM by 0.03 after poling. The depolarization temperature showed only slight variation in the pre-MPB compositions, but showed a minimum at the MPB compositions. Temperature dependent dielectric studies further showed that for the post-MPB compositions, the system remains relaxor even after poling.