With the rise of modern infrastructure and systems, testing and evaluation of specific components such as structural health monitoring is becoming increasingly important. Fiber optic sensors are ideal for testing and evaluating these systems due many advantages such as their lightweight, compact, and dielectric nature. This thesis presents a novel method for detecting electric fields in harsh environments with slab coupled optical sensors (SCOS) as well as a novel method for detecting strain gradients on a Hopkinson bar specimen using fiber Bragg gratings (FBG). Fiber optic electric field sensors are ideal for characterizing the electric field in many different systems. Unfortunately many of these systems such as railguns or plasma discharge systems produce one or more noise types such as vibrational noise that contribute to a harsh environment on the fiber optic sensor. When fiber optic sensors are placed in a harsh environment, multiple noise types can overwhelm the measurement from the fiber optic sensor. To make the fiber optic sensor suitable for a harsh environment it must be able to overcome all these noise types simultaneously to operate in a harsh environment rather than just overcome a single noise type. This work shows how to eliminate three different noise types in a fiber optic sensor induced by a harsh environment simultaneously. Specifically, non-localized vibration induced interferometric noise is up converted to higher frequency bands by single tone phase modulation. Then localized vibrational noise, and radio frequency (RF) noise are all eliminated using a push-pull SCOS configuration to allow for an optical measurement of an electric field in a harsh environment. The development and validation of a high-speed, full-spectrum measurement technique is described for fiber Bragg grating sensors in this work. A fiber Bragg grating is surface mounted to a split Hopkinson tensile bar specimen to induce high strain rates. The high strain gradients and large strains which indicate material failure are analyzed under high strain rates up to 500 s-1. The fiber Bragg grating is interrogated using a high-speed full-spectrum solid state interrogator with a repetition rate of 100 kHz. The captured deformed spectra are analyzed for strain gradients using a default interior point algorithm in combination with the modified transfer matrix approach. This work shows that by using high-speed full-spectrum interrogation of a fiber Bragg grating and the modified transfer matrix method, highly localized strain gradients and discontinuities can be measured without a direct line of sight.

This research presents the first use of side-polished Panda fiber in the fabrication of slab-coupled optical sensors (SCOS). It is determined that the Panda SCOS provides a sensor that is comparable to the D-fiber SCOS in cases of electric field sensing. It exhibits greater power transfer and higher bandwidth than a typical D-SCOS. The Panda SCOS is also less costly and easier to splice than the D-fiber alternative. This comes at a cost of slightly decreased sensitivity and a more fragile fabrication process. This research also demonstrates the use of the Panda-SCOS as means of voltage characterization across both the spark gap of an ignition coil circuit along with the spark gap of an automobile. This paper demonstrates the use of a Panda SCOS to measure the voltages and time delays across the spark gaps at different stages of a Marx generator setup .

The majority of Swedish boys and girls have good psychosomatic health. Despite that the risk of mental health problems such as nervousness, feeling low and sleeping difficulties has increased steadily in recent decades. Moreover, previous surveys on health and well-being indicate that boys and girls of foreign extraction in Sweden are at increased risk of ill health compared to boys and girls of Swedish background.   The main aim of this thesis was to analyse health and social determinants among boys and girls of foreign extraction in Sweden. The factors explored in papers I–IV include parental background, family affluence and gender and their associations with subjective health complaints, psychosomatic problems or health risk behaviours. Other included risk factors for ill health were involvement in bullying, low participation and discrimination at school. This thesis takes an intersectional perspective, with ambitions to be able to emphasize the interplay between different power relations (i.e. gender, social class and parental background).   Two sets of cross-sectional data were used. Three papers were based on the Swedish part of the World Health Organization’s Health Behaviour in School-Aged Children. The sample consisted of 11,972 children (boys n = 6054; girls n = 5918) in grades five, seven and nine from the measurement years 1997/98, 2001/02 and 2005/06. The response rate varied between 85 and 90%. About one fifth of the included children were of foreign extraction. For the fourth paper regional data from Northern Sweden were used. Boys (n = 729) and girls (n = 798) in grades six to nine answered a questionnaire in 2011 and the response rate was 80%. About 14% of the included children were of foreign extraction. Statistical methods used were chi-square test, correlation analyses, logistic regression analyses, cluster analyses and test of mediating factor.   The results showed that girls of foreign background were at increased risk of subjective health complaints (SHC) and boys of mixed background were at increased risk of psychosomatic problems (PSP). Increased risk of allocation to the cluster profile of multiple risk behaviour was shown in boys and girls of mixed background, in girls of foreign background and in girls of low family affluence. Increased risk of allocation to the cluster profile of inadequate tooth brushing was shown in boys and girls of foreign background and in girls of low family affluence. General risk factors for increased risk of ill health for boys and girls in Sweden were: any form of bullying involvement, low family affluence, low participation and discrimination at school, of which the latter also was a mediating factor for ill health. Living with a single parent was a risk factor for ill health among girls.   The results can function as a basis for developing health promotion programmes at schools that focus on social consequences of foreign extraction, family affluence, participation as well as health risk behaviours and gender. / Majoriteten av flickorna och pojkarna i Sverige har en god psykosomatisk hälsa. Trots det har risken för psykiska hälsosymptom såsom nervositet, att känna sig nere och sömnsvårigheter ökat successivt de senaste årtiondena. Dessutom indikerar tidigare forskning angående hälsa och välmående att flickor och pojkar med utländsk härkomst har ökad risk för ohälsa jämfört med flickor och pojkar med svensk härkomst.   Denna avhandlings huvudsyfte var att analysera hälsa och sociala bestämningsfaktorer bland flickor och pojkar i Sverige, med fokus på föräldrabakgrund. Artiklarnas (I–IV) syften inkluderar föräldrahärkomst, familjens materiella tillgångar och genus samt dess samband med subjektiva hälsobesvär, psykosomatiska problem eller hälsoriskbeteenden. Andra riskfaktorer för ohälsa som inkluderades var inblandning i mobbning, lågt deltagande och förekomst av diskriminering på skolan. Denna avhandling beaktar ett intersektionellt perspektiv med ambitionen att kunna tydliggöra samspelet mellan olika maktordningar (dvs. genus, social klass och föräldrabakgrund).   Två dataset från tvärsnittsstudier har använts. I de tre första artiklarna användes World Health Organization – Health Behaviour in School-Aged Children, som i Sverige heter Svenska skolbarns hälsovanor. Studiepopulationen bestod av 11 972 barn (flickor n = 5918; pojkar n = 6054) i årskurserna fem, sju och nio undersöknings år 1997/98, 2001/02 och 2005/06. Svarsfrekvensen var mellan 85 och 90 %. Ungefär en femtedel av barnen som deltog hade utländsk härkomst. I den fjärde artikeln användes regional data från norra Sverige. Flickor (n = 798) och pojkar (n = 729) i årskurserna sex till nio deltog i studien år 2011, svarsfrekvensen var 80 %. Omkring 14 % av barnen hade utländsk härkomst. De statistiska metoder som användes var sambandstest (chi-två), test av linjära samband så kallade korrelationsanalyser, logistisk regressionsanalys, klusteranalys och test av medierande faktor.   Resultaten visade att flickor med utländsk bakgrund hade ökad risk för subjektiva hälsobesvär (SHC) och pojkar av mixbakgrund hade ökad risk för psykosomatiska problem (PSP). Ökad risk för att hamna i klusterprofilen multipelt hälsoriskbeteende hade flickor och pojkar med mixbakgrund, flickor med utländsk bakgrund samt flickor i familjer med låg nivå av materiella tillgångar. Ökad risk för att hamna i klusterprofilen bristande tandborstning hade flickor och pojkar med utländsk bakgrund och flickor i familjer med låg nivå av materiella tillgångar. Generella riskfaktorer för ohälsa bland flickor och pojkar i Sverige var: alla former av inblandning i mobbning, låg nivå av materiella tillgångar i familjen, lågt deltagande och förekomst av diskriminering på skolan, vilken den senare även var en medierande faktor för ohälsa. Att leva med en ensamstående förälder var en riskfaktor för ohälsa bland flickor.   Avhandlingens resultat kan ligga till grund för utformande av hälsofrämjande interventioner inom elevhälsan, till exempel interventioner som fokuserar på sociala konsekvenser av utländsk härkomst, familjens materiella tillgångar, deltagande och diskriminering samt hälsoriskbeteenden och genus.

This thesis discusses the application of Slab Coupled Optical Fiber Sensors (SCOS) in a railgun. The specific goal of these sensors is to create an electric field profile at a specific point in the gun as the armature passes. The thesis explores the theory that powers the railgun as well as the principles of the SCOS sensors. It also elaborates on the various noise sources found throughout the detection system and concludes with a summary of the various field tests that were performed throughout this project. There are many benefits to using a railgun over traditional weapons in the field. These benefits not only include both safety and cost, but also greater overall defense capabilities. Unfortunately, the velocity skin effect (VSE) causes the current railgun designs to have limited life span through wear on the rails. In order to develop superior railguns and railgun armatures, the accurate detection of the VSE through measuring the electric field is of great interest. We used a SCOS, a small directionally precise dielectric sensor, as a small sensing area is required to be able to measure the electric fields inside of the rail gun. The actual usage of the SCOS within the railgun produced an additional set of problems that are not commonly encountered in the lab. The chief amongst these was noise from strain, RF pickup, and phase noise. This thesis also reports various methods used to reduce each of these noise sources.

A slab-coupled optical fiber sensor (SCOS) falls into a narrow class of all-dielectric optical fiber electric field sensors, which makes it a perfect candidate for measurements of high electric fields in environments where presence of conductors is highly perturbing to the system under test. Its nonlinear response to high fields requires a new nonlinear calibration technique. A nonlinear calibration method is explained and demonstrated to successfully measure high electric fields, as well as high voltages with dynamic range up to 50 dB. Furthermore, a SCOS can be fitted into narrow spaces and make highly localized measurements due to its small size. This allows a SCOS to be integrated inside a standard high voltage coaxial cable, such as RG-218. Effects of partial discharge and arcing is minimized by development of a fabrication method to avoid introduction of impurities, especially air-bubbles, into the cable during SCOS insertion. Low perturbation of the measured voltage is shown by simulating the introduced voltage reflections to be on the order of –50 dB. It is also shown that a SCOS can be inserted into other cables without significant perturbation to the voltage. A complete high voltage and high electric field measurement system is built based on the high-voltage modifications of the SCOS technology. The coaxial SCOS is enhanced for robustness. Enhancements include packaging a SCOS into stronger ceramic trough, strengthening the fiber with kevlar reinforced furcation tubing and protecting the sensor with metal braces and protective shells. The interrogator is protected from electromagnetic interference with an RF-shielded box. Reduction in power losses introduced by the new PANDA-SCOS technology allows interrogator bandwidths to be increased up to 1.2 GHz. The whole measurement process is streamlined with dedicated software, developed specifically for high voltage and electric field measurements with support for the nonlinear calibration.

A slab-coupled optical fiber sensor (SCOS) falls into a narrow class of all-dielectric optical fiber electric field sensors, which makes it a perfect candidate for measurements of high electric fields in environments where presence of conductors is highly perturbing to the system under test. Its nonlinear response to high fields requires a new nonlinear calibration technique. A nonlinear calibration method is explained and demonstrated to successfully measure high electric fields, as well as high voltages with dynamic range up to 50 dB. Furthermore, a SCOS can be fitted into narrow spaces and make highly localized measurements due to its small size. This allows a SCOS to be integrated inside a standard high voltage coaxial cable, such as RG-218. Effects of partial discharge and arcing is minimized by development of a fabrication method to avoid introduction of impurities, especially air-bubbles, into the cable during SCOS insertion. Low perturbation of the measured voltage is shown by simulating the introduced voltage reflections to be on the order of −50 dB. It is also shown that a SCOS can be inserted into other cables without significant perturbation to the voltage.A complete high voltage and high electric field measurement system is built based on the high-voltage modifications of the SCOS technology. The coaxial SCOS is enhanced for robustness. Enhancements include packaging a SCOS into stronger ceramic trough, strengthening the fiber with kevlar reinforced furcation tubing and protecting the sensor with metal braces and protective shells. The interrogator is protected from electromagnetic interference with an RF-shielded box. Reduction in power losses introduced by the new PANDA-SCOS technology allows interrogator bandwidths to be increased up to 1.2 GHz. The whole measurement process is streamlined with dedicated software, developed specifically for high voltage and electric field measurements with support for the nonlinear calibration.

This thesis presents a solution for mission operation automation in European Space Agency’s (ESA) OPS-SAT mission. To achieve this, the ESA internal mission automation system (MATIS) in combination with the mission control software (SCOS) are used. They control the satellite and all ground peripherals and programmes to enable fully automated and unsupervised satellite passes. The goal of this work is the transition from the existing manual operation, with a human operator watching over and controlling all systems, to an automated system. This system supports the operation engineer and replaces the operator himself. A large section of this thesis consists of the setup, configuration, integration of all programmes and virtual machines and testing of the MATIS software, as well as the Service Management Framework (SMF) which connects MATIS to non-MATIS applications like SCOS. During testing, many problems could be identified, not only OPS-SAT specific ones, but also general problems applying to all missions that consider using MATIS for future operation automation. These findings and bugs discovered during testing are reported to the responsible authorities and presented in this work. Further features of this thesis are the elaborations of the mission operation automation concept and the satellite pass concept, providing an in-depth view of the automation and passes of OPS-SAT as well as the general concepts and thoughts, which can be used by other missions to accelerate integration. An additional key feature of this thesis is the newly developed standard for operation notation in Excel, which has been achieved in close cooperation with the operation engineer. Furthermore, to accelerate the process of switching from manual to automated procedures, several converters have been developed iteratively with the new standard. These converters allow fast transformation from Excel to the procedure programming language called PLUTO used by MATIS. Not only do the results and converters of this work accelerate the procedure integration by 80%, they also deliver a more stable mission automation system that can be used by other missions as well. Operation automation reduces the operational costs for satellites and space missions significantly, as well as reducing the human error to a minimum. Therefore, this thesis is the first step towards a future with complete automation in the area of satellite operations. Without this automation, future satellite cluster configurations, like Starlink from SpaceX, will not be possible to put into practice, due to their high complexity, exceeding the comprehensibility and reaction time of humans.