abstract: Micro Electro Mechanical Systems (MEMS) is one of the fastest growing field in silicon industry. Low cost production is key for any company to improve their market share. MEMS testing is challenging since input to test a MEMS device require physical stimulus like acceleration, pressure etc. Also, MEMS device vary with process and requires calibration to make them reliable. This increases test cost and testing time. This challenge can be overcome by combining electrical stimulus based testing along with statistical analysis on MEMS response for electrical stimulus and also limited physical stimulus response data. This thesis proposes electrical stimulus based built in self test(BIST) which can be used to get MEMS data and later this data can be used for statistical analysis. A capacitive MEMS accelerometer is considered to test this BIST approach. This BIST circuit overhead is less and utilizes most of the standard readout circuit. This thesis discusses accelerometer response for electrical stimulus and BIST architecture. As a part of this BIST circuit, a second order sigma delta modulator has been designed. This modulator has a sampling frequency of 1MHz and bandwidth of 6KHz. SNDR of 60dB is achieved with 1Vpp differential input signal and 3.3V supply / Dissertation/Thesis / M.S. Electrical Engineering 2013

abstract: "Sensor Decade" has been labeled on the first decade of the 21st century. Similar to the revolution of micro-computer in 1980s, sensor R&D; developed rapidly during the past 20 years. Hard workings were mainly made to minimize the size of devices with optimal the performance. Efforts to develop the small size devices are mainly concentrated around Micro-electro-mechanical-system (MEMS) technology. MEMS accelerometers are widely published and used in consumer electronics, such as smart phones, gaming consoles, anti-shake camera and vibration detectors. This study represents liquid-state low frequency micro-accelerometer based on molecular electronic transducer (MET), in which inertial mass is not the only but also the conversion of mechanical movement to electric current signal is the main utilization of the ionic liquid. With silicon-based planar micro-fabrication, the device uses a sub-micron liter electrolyte droplet sealed in oil as the sensing body and a MET electrode arrangement which is the anode-cathode-cathode-anode (ACCA) in parallel as the read-out sensing part. In order to sensing the movement of ionic liquid, an imposed electric potential was applied between the anode and the cathode. The electrode reaction, I_3^-+2e^___3I^-, occurs around the cathode which is reverse at the anodes. Obviously, the current magnitude varies with the concentration of ionic liquid, which will be effected by the movement of liquid droplet as the inertial mass. With such structure, the promising performance of the MET device design is to achieve 10.8 V/G (G=9.81 m/s^2) sensitivity at 20 Hz with the bandwidth from 1 Hz to 50 Hz, and a low noise floor of 100 ug/sqrt(Hz) at 20 Hz. / Dissertation/Thesis / M.S. Electrical Engineering 2013

abstract: This thesis presents approaches to develop micro seismometers and accelerometers based on molecular electronic transducers (MET) technology using MicroElectroMechanical Systems (MEMS) techniques. MET is a technology applied in seismic instrumentation that proves highly beneficial to planetary seismology. It consists of an electrochemical cell that senses the movement of liquid electrolyte between electrodes by converting it to the output current. MET seismometers have advantages of high sensitivity, low noise floor, small size, absence of fragile mechanical moving parts and independence on the direction of sensitivity axis. By using MEMS techniques, a micro MET seismometer is developed with inter-electrode spacing close to 1μm, which improves the sensitivity of fabricated device to above 3000 V/(m/s^2) under operating bias of 600 mV and input acceleration of 400 μG (G=9.81m/s^2) at 0.32 Hz. The lowered hydrodynamic resistance by increasing the number of channels improves the self-noise to -127 dB equivalent to 44 nG/√Hz at 1 Hz. An alternative approach to build the sensing element of MEMS MET seismometer using SOI process is also presented in this thesis. The significantly increased number of channels is expected to improve the noise performance. Inspired by the advantages of combining MET and MEMS technologies on the development of seismometer, a low frequency accelerometer utilizing MET technology with post-CMOS-compatible fabrication processes is developed. In the fabricated accelerometer, the complicated fabrication of mass-spring system in solid-state MEMS accelerometer is replaced with a much simpler post-CMOS-compatible process containing only deposition of a four-electrode MET structure on a planar substrate, and a liquid inertia mass of an electrolyte droplet encapsulated by oil film. The fabrication process does not involve focused ion beam milling which is used in the micro MET seismometer fabrication, thus the cost is lowered. Furthermore, the planar structure and the novel idea of using an oil film as the sealing diaphragm eliminate the complicated three-dimensional packaging of the seismometer. The fabricated device achieves 10.8 V/G sensitivity at 20 Hz with nearly flat response over the frequency range from 1 Hz to 50 Hz, and a low noise floor of 75 μG/√Hz at 20 Hz. / Dissertation/Thesis / Ph.D. Electrical Engineering 2014

Introdução: Estudos mostram a importância de quantificar a atividade física e sua associação no processo saúde-doença. Esta tarefa não é simples, principalmente em crianças, por constituir um construto multidimensional que envolve atividades realizadas no lazer, em ambientes educacionais, vinculadas à ocupação e ao transporte. O acelerômetro está em destaque nos estudos epidemiológicos com adultos e crianças nos quais existe interesse na aferição de atividade física. Objetivo: Explorar aspectos metodológicos na aferição de atividade física por meio de acelerômetro em crianças de 7 a 10 anos. Metodologia: Estudo de revisão sistemática de trabalhos selecionados segundo passos pré-definidos: critérios de inclusão dos estudos; estratégia de busca; critérios para avaliação de qualidade dos estudos identificados; informações a serem extraídas. Entre as características de interesse estão as relacionadas à tecnologia do equipamento, à utilização, à população e às medidas de aferição. Resultados: Foram localizados 872 trabalhos nas 4 bases de dados (Pubmed, Embase, SPORTDiscus, Lilacs). Foram incluídos na revisão 68 estudos com qualidade metodológica. Foi constatada a predominância de utilização de acelerômetros uniaxiais da marca Actigraph® (Modelos: GT1M; 7164), com sua maior utilização na região do quadril direito, por sete dias da semana, com epochs de duração de 60 segundos, considerando como válida a informação de 3 ou mais dias de coleta e a presença de grande variedade de pontos de corte para diferentes níveis de intensidade e desfechos da atividade física. Conclusão: O acelerômetro é bastante utilizado em pesquisas epidemiológicas na aferição de atividade física por meio de counts, uma medida que não apresenta fácil entendimento. São aspectos metodológicos que limitam a comparação entre os estudos: diferentes marcas e modelos, diferentes número de dias de observação, grande variabilidade nas faixas etárias, diferentes durações do epoch e de pontos de corte. Identifica-se a necessidade de mais estudos metodológicos para elucidar a aplicabilidade do acelerômetro como instrumento de aferição da atividade física em crianças de 7 a 10 anos / Background: Studies have shown the importance of quantifying physical activity and its association in health-disease process. This task is not easy, especially in children, because it represents a multidimensional construct that involves leisure activities, educational settings, linked to occupation and transportation. The accelerometer is frequently used in epidemiological studies with adults and children where there is interest in assessing physical activity. Objective: To explore methodological aspects in physical activity assessment using accelerometer among children aged 7 to 10 years. Methodology: Systematic literature review of studies selected according to pre-defined steps: inclusion criteria studies; search strategy, quality assessment criteria of studies identified; information to be extracted. Among the interest features, may be mentioned those related to the technology of the accelerometer, group of age and outcome measures. Results: It was found 872 papers in four databases (PubMed, Embase, SPORTDiscus, Lilacs). Were included in the review, 68 studies showed methodological quality. It was found the predominant equipament was the uniaxial accelerometers Actigraph® (Models: GT1M, 7164), frequently fixated on the right hip, seven days a week, with epochs lasting 60 seconds, for valid the information it was observed 3 or more days of collection and the presence of a large variety of cutoff points for intensity levels and physical activity outcomes. Conclusion: The accelerometer is used in epidemiological research on the assessment of physical activity considering counts as measure but it has no easy understanding. The results depend on methodological aspects that limitate the use of this equipament such as differents brands and models, fixation sites, as well as different number of days of observation, very large group of age, different epoch duration and cutoff points for outcame definition. We identified the need for more methodological studies to elucidate the applicability of the accelerometer in children aged 7 to 10 years

INTRODUÇÃO: A atividade física regular trás benefício à saúde, reduzindo a obesidade, morbidades e a mortalidade e, em pacientes asmáticos, a atividade física melhora os sintomas da doença. Apesar disso, ainda existe divergência na literatura se crianças asmáticas são fisicamente ativas, e isto parece depender do método empregado, da gravidade da doença e do controle clínico. OBJETIVO: Comparamos a atividade física de vida diária (AFVD) entre crianças com diferentes gravidades da asma e identificamos fatores que possam dificultar a realização das AFVD. MÉTODO: Estudo transversal com 121 crianças, sendo 79 asmáticas das quais (32 asma persistente leve, 24 asma persistente moderada, 23 asma persistente grave) e 42 controles, de ambos os sexos, com idade entre 7 a 12 anos. As crianças asmática estavam em tratamento médico há, no mínimo, 6 meses e com a doença controlada. O nível de AFVD foi monitorado com um acelerômetro durante 6 dias (4 dias da semana e 2 de final de semana). A função pulmonar e as barreiras que dificultam a realização da AFVD também foram avaliadas. RESULTADOS: Os nossos resultados mostraram que o número total de passos, e as atividades realizadas em intensidade moderada foram similares entre as crianças com as diferentes gravidades da asma. O percentual de crianças asmáticas fisicamente ativas foi similar quando comparado com as crianças sem asma (respectivamente, 51,9% vs. 50%; p>0,05). Não foi observada diferença nos parâmetros funcionais da função pulmonar (obstrução fixa, resposta ao broncodilatador e variabilidade do VEF1) entre as crianças asmáticas fisicamente ativas e as sedentárias (p>0,05). Porém, foi observado um maior percentual de crianças com sobrepeso ou obesidade entre os asmáticos sedentários quando comparado às crianças fisicamente ativas (respectivamente, 24,1% vs. 11,1%; p<0,05). As barreiras ambientais foram as mais relatadas pelas crianças com e sem asma (p>0,05), porém este fator foi relatado em maior proporção pelas crianças asmáticas sedentárias quando comparado àquelas fisicamente ativas (respectivamente, 34,2% vs. 14,6%; p<0,05). CONCLUSÕES: As crianças asmáticas com a doença controlada tiveram o mesmo nível de AFVD entre as diferentes gravidades da doença e que seus pares sem asma. A gravidade da doença, fatores ligados à função pulmonar e a percepção da doença como barreira para atividade física pareceu não estar associadas ao sedentarismo. As barreiras ambientais foram as mais relatadas pelas crianças com e sem asma, porém, nas crianças asmáticas sedentárias essas barreiras pareceram ser ainda mais relevantes / BACKGROUND: Regular physical activity promotes health benefits by reducing obesity, morbidity and mortality, and who has asthma, physical activity improves the symptoms of disease. Nevertheless, there is disagreement in the literature whether asthmatic children are physically active, and this seems to depend on the method used, severity of disease and clinical control. OBJECTIVE: We compared Daily Physical Activity (DPA) among children of different severity levels of asthma and we have identified factors that may hinder DPA. METHOD: Cross-Sectional study with 121 children, 79 with asthma (32 mild persistent asthma, 24 moderate persistent asthma, 23 severe persistent asthma) and 42 children without asthma, of both sexes, aged between of 7 and 12 years. The asthmatic children were under medical treatment for at least 6 months and the disease controlled. DPA was monitored with an accelerometer for 6 days (4 weekdays and 2 weekends). Pulmonary function and barriers that hinder DPA were also assessed. RESULTS: Our results showed that the total number of steps, and the activities performed at moderate intensity were similar between children with different severities of asthma. The percentage of physically active children with asthma was similar when compared with children without asthma (respectively, 51,9% vs. 50%; p>0,05). There was no difference in respiratory function parameters (fixed obstruction, bronchodilator response and variability of FEV1) among the asthmatic children physically active and sedentary (p> 0.05). However, we found that sedentary asthmatic children were more overweight or obese than physically active asthmatic children (respectively, 24,1% vs. 11,1%; p<0,05). The environmental barriers were the most frequently reported by children with and without asthma (p> 0,05), but this factor was reported in a higher proportion by sedentary asthmatic children compared to those physically active (respectively, 34,2% vs. 14,6%; p<0,05). CONCLUSIONS: Clinically controlled asthmatic children had the same level of DPA between different severities of asthma and their peers without asthma. The severity of disease, factors related to lung function and perception of disease as a barrier to physical activity did not seem be associated with sedentary lifestyle. The environmental barriers were the most frequently reported by children with and without asthma, however in sedentary asthmatic children these barriers seemed to be even more relevant

Master of Science / Department of Electrical and Computer Engineering / Steven Warren / A reference design for a wearable, wireless biomedical sensor set has been a long-term need for researchers at Kansas State University, driven by the idea that a basic set of sensor components could address the demands of multiple types of human and animal health monitoring scenarios if these components offered even basic reconfigurability. Such a reference design would also be a starting point to assess sensor performance and signal quality in the context of various biomedical research applications. This thesis describes the development of a set of wireless health monitoring sensors that can be used collectively as a data acquisition platform to provide biomedical research data and to serve as a baseline reference design for new sensor and system development. The host computer, an Intel Edison unit, offers plug-and-play usability and supports both Wi-Fi and Bluetooth wireless connectivity. The reference sensor set that accompanies the Intel Edison single-board computer includes an electrocardiograph, a pulse oximeter, and an accelerometer/gyrometer. All sensors are based on the same physical footprint and connector placement so that the sensors can be stacked to create a collection with a minimal volume and footprint. The latest hardware version is 3.1. Version 1.0 supported only a pulse oximeter, whereas version 2.0 included an electrocardiograph, pulse oximeter, and respiration belt. In version 3.0, the respiration belt was removed, and accelerometers and gyroscopes were added to the sensor set. Version 3.1 is a refined version of the latter design, where known hardware bugs were remedied. Future work includes the development of new sensors and casing designs that can hold these sensor stacks.

Since the mindstorm kit is widely used by students and beginners, demand of a commercial-free integrated embedded working environment turns up. With its help the limitation on working place and complexity of programming can be reduced.  The aim of this project is to use a combination of commercial-free softwares as an embedded working environment. The environment can deal with the mindstorm kit applications directly. In order to show the successful generation of the commercial-freesoftware's project an inverted pendulum is set up. Open source firmware of NXT-G is used to provide basic interface for invoking the functions in NXT master brick. Accelerometer is working as the sensor. The main dynamic controller falls on the PD controller to keep inverted pendulum in vertical and static state. As a result the inverted pendulum programmed in this working environment can keep balance for a couple of seconds.

Cette thèse porte sur le développement de méthodes et techniques expérimentales pour mieux connaître les principes à l’oeuvre dans les glissements de terrains, les avalanches, les écoulements granulaires qui ont un grand rôle dans la liquéfaction des sols, ayant pour conséquences possibles la chute ou l’enfoncement de bâtiments. On conjugue ici des expériences de géophysique expérimentale avec des expériences de physique des milieux granulaires, et en parallèle on développe des appareils de mesure basés sur des microcontrôleurs et capteurs embarqués. / The subject of this thesis are the methods and experimental technics to help in the assessment of the underlying principles for the landslides, runaways and the other phenomena playing a main role in soil liquefaction and hence, on the falling or settling of buildings. This thesis conjugates geophysics’ to granular materials physics’ experiments, and it allowed to develop new measurement devices based on embedded microcontrollers.

Sammanfattning Syfte: Syftet med studien var att undersöka om patienter som har kronisk obstruktiv lungsjukdom, KOL, efter deltagande i KOL-skola under sju veckor blir mer aktiva i sin vardag och ökar sin fysiska aktivitetsnivå samt relatera detta till förbättring i livskvalitet och fysisk kapacitet. Frågeställningarna var om det efter 7 veckors KOL-skola går att se en förbättring av den fysiska aktivitetsnivån mätt med accelerometer samt om fysisk kapacitet och prestationsförmåga förbättras mätt med 6-minuters gångtest? Kan det även visa på förändring i aktiviteter i dagliga livet, ADL (Aktiviteter i dagliga livet) och livskvalitet mätt med Eq5d samt minska upplevda besvär vid KOL mätt med CCQ- Chronic COPD Questionaire? Metod: Studien är en kvantitativ prospektiv cohort studie. Deltagarna i studien bestod av 25 patienter , kvinnor och män i åldrarna 45-90 år, med KOL i stadie 1-4. Patienterna deltog i en multidisciplinär KOL-skola under sju veckors tid med undervisning om KOL samt träning för kondition och styrka vid 12 tillfällen. Deltagarna utvärderades med accelerometer- en typ av rörelsemätare som mäter aktivitet i tre olika plan, 6-minuters gångtest, CCQ-chronic COPD questionnaire och Eq5ds hälsobarometer (0-100mm). Samtliga tester utfördes före och efter deltagandet i KOL-skolan. Accelerometermätningen skedde en vecka före starten samt en vecka efter avslut. Resultat: Ingen signifikant förbättring kunde visas gällande fysisk aktivitetsnivå, steg/dag (N.S p=0,330), stillasittande tid (N.S p=0,055), perioder av stillasittande (N.S p=0,875). Den fysiska kapaciteten, prestationsförmågan mätt med 6-minuters gångtest ökade signifikant med i snitt 60 meter (p=0,0002). ADL och livskvalitet mätt med Eq5ds hälsobarometer visade på signifikant förbättring från i snitt 56 mm före till 64 mm efter KOL-skolan (p=0,022) och patienterna skattade sina besvär 0,29 poäng mindre efter deltagandet från i snitt 2,32 till 2,03 poäng av maxpoäng 6,0 (p=0,046). Slutsats: Efter deltagandet i KOL-skolan under 7 veckor kunde studien påvisa en signifikant ökning i gångsträcka samt att patienterna skattade lägre besvär av andfåddhet vid fysiskt krävande aktiviteter. Patienterna förbättrade sitt psykiska välmående. Dock kunde ingen signifikant ökning i aktivitetsnivå, steg/dag påvisas men en tendens till att patienterna var mindre stillasittande kunde ses. / Abstract Aim: The aim of this study was to investigate if patients with chronic obstructive lung disease after seven weeks of pulmonary rehabilitation increased their activity in daily life and their physical activity level and relate this to increase in quality of life and physical capacity. The questions asked was if seven weeks of pulmonary rehabilitation could lead to an increase in physical activity level measured with accelerometer and if physical capacity and performance would increase measured with 6-minutes walking distance? Can this also lead to a change in ADL and quality of life measured with the Eq5d-questionaire and decrease the patient’s perceived inconvenience in COPD measured with CCQ? Method: The study is a quantitative prospective study. There were 25 participants in the study. Men and women in the ages 45-90 years, all diagnosed with COPD stage 1-4. All patients participated in a multidisciplinary rehabilitation during seven weeks including information about COPD and fitness- and strength training during 12 occasions. The participants were evaluated with accelerometer- a device that measures movement in three dimensions, 6-minutes walking distance, CCQ-chronic COPD questionnaire and Eq5d- health barometer (0-100mm). All evaluation was made before and after participating in pulmonary rehabilitation. Measurements with the accelerometers was made one week before the rehabilitation started and one week after it finished. Results: No significant improvements were found regarding physical activity level, step counts/day (N.S p=0.330), sedentary time (N.S p=0.055), periods of sedentary bouts (N.S p=0.875). Physical capacity and performance measured with 6-minutes walking distance showed a significant increase, on average 60 meters (p=0.0002). ADL and quality of life measured with Eq5d health barometer showed a significant improvement in average 56 mm before to 64 mm after participating in pulmonary rehabilitation (p=0.022) and the patients evaluated their perceived inconvenience 0.29 points less, from 2.32 to 2.03 points of a maximum score of 6.0 (p=0.046). Conclusions: After participating in pulmonary rehabilitation for 7 weeks the study could show a significant increase regarding walking distance and less perceived inconvenience from breathlessness at physical demanding activity. The patients increased their mental wellbeing but showed no significant increase regarding activity level or step counts/day, although a tendency that the patient were less sedentary could be seen.

With the advancements in technology and computing environment capabilities, the number of devices that people carry has increased exponentially. This increase initially occurred as a result of necessity to monitor the human body condition due to chronic diseases, heart problems etc. Later, individuals’ interest was drawn towards self-monitoring their physiology and health care. This is achieved by implanting various sensors that can proactively monitor the human body based on medical necessity and the health condition of the user. Sensors connected on a human body perceive phenomena such as locomotion or heartbeat, and act accordingly to form a Body Area Network. The primary concern of these sensors is to ensure a secure way of communication and coordination among the devices to form a flawless system. A secondary concern is wireless sensor authentication, which ensures trustworthiness and reliable gathering of a user’s data. To address this concern, we designed a secure approach using low cost accelerometers to authenticate sensors in Body Area Networks. To ensure authentication in on-body sensor networks, we need a mechanism which intuitively proves all the communicating nodes are trusted ones. In order to achieve sensor authentication, we used accelerometer data gathered from sensors to distinguish whether or not the devices are carried on waist of same individual’s body. Our approach is focused at analyzing walking patterns recorded from smartphone accelerometers placed in the same location of the user’s body, and we present results showing these sensors record similar pattern.