Over the last decades, the frequency on the Nordic electrical power grid has deteriorated. Therefore, new stricter requirements are developed for the hydropower delivering regulating active power on the Frequency Containment Reserve market (FCR). This thesis aims to investigate the possibility of modeling two double-regulated hydropower plants, referred to as Unit 1 and 2, to evaluate their compliance with the new FCR-requirements.  By modeling the hydropower plants, the first goal was to find a model structure that captures the essential dynamics of the systems. A second goal was to evaluate whether the two units currently fulfill the new FCR-requirements, and investigate how the turbine governors’ settings could be optimized to fulfill the new requirements. Data obtained from FCR-tests was used in MATLAB to evaluate the two stations’ dynamic stability and performance requirements. Through system identification in MATLAB, grey-box modeling was used to create linear and non-linear turbine and waterways models for Unit 1 and Unit 2. The non-linear turbine and waterways models were implemented in Simulink, together with corresponding turbine governors, to find optimal parameter settings to fulfill the FCR-requirements.  The evaluation of the new FCR-requirements shows that none of the two units fulfills the dynamic stability requirement. However, Unit 1 fulfills the performance requirement. The results imply that double-regulated turbines will most likely have difficulties fulfilling the new requirements, which will cause major consequences in improving the frequency regulation quality. The results from the grey-box modeling present that the linear models are not validated with the step response data, due to not capturing the system dynamics when compared with provided data from the units. On the other hand, the non-linear models are validated with step response data as the model captures the system dynamics more accurately. However, the non- linear Simulink models cannot capture the dynamics of the hydropower systems for sinusoidal signals with varying frequencies which are used in the new FCR-requirement test. Consequently, the thesis has no result of the optimal parameter setting of the turbine governors to fulfill the new FCR-requirements. In conclusion, the grey-box models, with the level of detail presented in this thesis, are inadequate in capturing the system’s dynamics to evaluate the new FCR-requirements. Thus, the thesis contributes to filling a knowledge gap within the area of modeling for frequency regulation.

In many physical activities, exercise is not continuous, but intermittent: it involves a sequence of exercise fractions at varying intensities, some higher than others. In planned training, this type of exercise is found in the form of high intensity interval training (HIIT), which is an effective and time-efficient approach that has been popular in high-performance sports over the last century, and in clinical settings for the past twenty years. Models are available to predict performance during continuous exercise (without intensity variation) over various durations. The ecological validity of some continuous exercise models has been reported. However, this is not the case for intermittent exercise, which has several parameters that can be modified, leading to a large variation in individual responses. The purpose of this master’s thesis is to compare the major models of intermittent exercise and determine their strengths and weaknesses, the constructs on which they are based, and their applicability to various physical activities. The master’s thesis also reviews the evolution of continuous exercise models to better understand the elements that need to be considered to improve the validity of intermittent exercise modelling. Due to the lack of quality data to compare a set of HIIT sessions of the same degree of difficulty, the thesis presents a study that uses simulations to identify the main limitations of the intermittent exercise models included in commercial applications, i.e., the Coggan and Skiba models. The study reveals the limitations of these models in prescribing sessions with a low number of repetitions performed at supramaximal intensity, interspersed with long recovery periods. The main intermittent exercise models have limitations that restrict their widespread use. In order for intermittent exercise modelling to evolve into more valid models that improve understanding of the physiological phenomena involved, it is crucial that the models be tested against a robust set of comparable intermittent exercise data. The thesis draws a detailed portrait of the continuous and intermittent exercise models, accounts for their evolution over time, and provides elements to guide future exercise modelling. Finally, the thesis identifies the limits of the current intermittent exercise models, makes recommendations to sports practitioners to promote their good use, and proposes a modification to the Coggan model that reduces its limitations. / Dans plusieurs activités physiques, l’exercice n’est pas continu, mais intermittent : il comprend un enchaînement de fractions d’exercice à des intensités variées, certaines plus élevées que d’autres. Dans l’entraînement planifié, on retrouve ce type d’exercice sous la forme de l’entraînement par intervalles (EPI), qui est une approche efficace et économe en temps, très populaire dans les milieux sportifs depuis plus d’un siècle, et dans les milieux cliniques depuis plus d’une vingtaine d’années. Des modèles sont disponibles permettant de prédire les performances lors de l’exercice continu (sans variation d’intensité) sur des durées variées. La validité écologique de certains modèles de l’exercice continu a été rapportée, montrant leur capacité à s’appliquer aux situations observées sur le terrain. Ce n’est toutefois pas le cas pour l’exercice intermittent, qui comporte plusieurs paramètres pouvant être modifiés, et menant à une grande variation des réponses individuelles. L’objectif du mémoire est de comparer les principaux modèles de l’exercice intermittent et déterminer leurs forces et leurs faiblesses, les construits sur lesquels ils sont fondés, et leur applicabilité dans diverses activités physiques. Il s’agit aussi de revoir l’évolution des modèles de l’exercice continu pour mieux comprendre les éléments à considérer pour améliorer la validité de la modélisation de l’exercice intermittent. Face au manque de données de qualité permettant de comparer un ensemble de séances d’EPI de même degré de difficulté, le mémoire présente une étude qui procède par simulations pour identifier les principales limites des modèles de l’exercice intermittent inclus dans des applications commerciales, soit les modèles de Coggan et de Skiba. L’étude révèle les limites de ces modèles quant à la prescription de séances comprenant un faible nombre de répétitions effectuées à intensité supramaximale, entrecoupées de longues périodes de récupération. Les principaux modèles de l’exercice intermittent présentent des limites restreignant leur utilisation généralisée. Pour que la modélisation de l’exercice intermittent évolue vers des modèles plus valides, permettant d’améliorer la compréhension des phénomènes physiologiques en jeu, il est crucial de confronter les modèles à un ensemble robuste de données comparables de l’exercice intermittent. Le mémoire dresse un portrait détaillé des modèles de l’exercice continu et intermittent, fait état de leur évolution au fil du temps, et propose des éléments pour guider la suite des travaux de modélisation. Enfin, le mémoire identifie les limites des modèles de courants de l’exercice intermittent, présente des recommandations aux intervenants sportifs pour favoriser la bonne utilisation de ceux-ci, en plus de fournir une modification du modèle de Coggan qui diminue les limites de celui-ci.

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My dissertation combines structural macroeconomic models with analyses of macro and micro data and broadly contributes to two research agendas. The first relates to the channels through which monetary policy impacts the economy. The second aims to understand how heterogeneity observed at the micro level affects the economy. The first two chapters, "Monetary Policy and Heterogeneous Mortgage Refinancing" and "A Model of Heterogeneous Mortgage Refinancing," focus on the refinancing channel of monetary policy. Since fixed-rate mortgages are the most significant source of household debt in the U.S., monetary policy can stimulate household consumption and wealth by lowering mortgage costs through refinancing. The potency of this channel will depend on households’ outstanding mortgage rates, as well as their willingness and ability to refinance. I combine empirical patterns from monthly loan-level data (from joint work with A.Burya) and a heterogeneous agent model of mortgage refinancing to show that credit score heterogeneity dampens the aggregate consumption response to monetary policy by 11%. The third and fourth chapters, "Anchoring of Inflation Expectations: An Empirical Test" and "Anchoring of Inflation Expectations: Role of Risk Premia," study the effectiveness of monetary policy in the U.S. by exploring the degree to which inflation expectations are anchored. If inflation expectations are well-anchored, then the Fed has a higher capacity to support aggregate employment when necessary, without destabilizing inflation. In joint work with A. Burya and S. Mishra, I construct a proxy of the change in the Fed's aggressiveness to inflation and develop an empirical test for inflation expectations anchoring. The proxy of the changes in the Fed's aggressiveness is equal to changes in expectations of future policy rates that are unexplained by the information contained in the inflation news release. The empirical test involves examining the sensitivity of inflation expectations to monetary policy shocks conditional on that proxy. I then use a measure of inflation expectations adjusted for inflation and liquidity risk premia to demonstrate that bond yield data in the U.S. is consistent with the anchoring of the long-term inflation expectations.

Purpose of Review: Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) have emerged as the invasive diagnostic tools of choice for hemodynamic assessment of the severity of CAD (coronary artery disease). We sought to comprehensively review the evidence on the utility of hemodynamic assessment of the coronary stenoses after percutaneous coronary intervention (PCI) using FFR/iFR, mechanisms of positive post-PCI iFR/FFR, and the clinical impact of significant residual ischemia. Recent Findings: The evidence on the utility of the post-PCI hemodynamic assessment has accumulated over the last few years. The post hoc analysis from the FAME 1 and FAME 2 data shows that higher post-PCI FFR is associated with better symptomatic improvement and lower event rate with larger increase in delta FFR (∆ FFR: post-PCI FFR – pre-PCI FFR). Unlike pre-PCI FFR, a consensus has not been established on the optimal value of post-PCI FFR, though multiple studies point toward better clinical outcomes with higher post-PCI FFR and larger ∆ FFR. Summary: Visual assessment of adequate stent apposition by coronary angiography is insufficient in evaluating for residual ischemia. The hemodynamic evaluation of residual ischemia by post-PCI FFR/iFR yields clinically relevant data and allows for appropriate post PCI optimization.

Sverige påbörjade en upprustning efter Rysslands invasion av Ukraina 2014. Debatten kring Sveriges försvarsförmåga har under den gångna våren åter igen aktualiserats och kommit på allas läppar på grund av Rysslands senaste invasion av Ukraina. Sveriges regering har beslutat att Försvarsmakten ska få ökade ekonomiska anslag och att organisationen ska utökas personellt. En stor del av Arméns förband kommer i framtiden allt utgöras av tidvis tjänstgörande personal, dvs reservofficerare, tidvis tjänstgörande soldater samt värnpliktiga. De här personalkategorierna behöver både upprätthålla sin kompetens och utvecklas för att fylla sin plats i krigsorganisationen. I dagsläget när reservofficerare kallas till tjänstgöring i samband med utbildning eller träning är deltagandet frivilligt. Försvarsmaktens uppfattning är att knappt hälften av Sveriges ca 6 800 reservofficerare har övat sedan 2014. Syftet med studien är att utforska vad som motiverar respektive vad som uppfattas som försvårande eller rent hindrande faktorer till tjänstgöring för reservofficerarna vid Skaraborgs regemente. Studiens fokus är på vad som engagerar dem att tjänstgöra i Försvarsmakten och vad som kan öka deras motivation. Studien baseras på intervjuer. Den insamlande empirin är analyserad med Grounded theory. I analysen kombineras två olika teorier om motivation för att förstå reservofficerarnas situation. Amitai Etzionis Compliance theory, en teori kring hur olika styrformer inom organisationer korrelerar med motivation, kombineras med Herzberg, Mausner och Snydermans The motivation to work, en teori om motivation på arbetsplatsen. Reservofficerarna upplever i grunden att tjänstgöringen är motiverande och Försvarsmakten skall fortsätta stärka relationen med sina anställda och dra nytta av förbandsandan. Studien har identifierat fem huvudsakliga områden som påverkar reservofficerarnas engagemang: militära miljön, kommunikation, växelverkan, regler samt lön och ersättning. Den speciella miljön som uppstår i Försvarsmakten är den enskilt mest motiverande faktorn för tjänstgöring. Det är en miljö som de intervjuade reservofficerarna trivs i, en miljö som de dessutom uppger är svår att finna någon annanstans. Miljön består av den unika kombinationen militära kontexten, relationen till kollegorna och känslan av att tillhöra något större. / Sweden began a rearmament after Russia's invasion of Ukraine in 2014. The debate over Sweden's defense capability has again been brought to the fore again this spring and has come to everyone's lips due to Russia's latest invasion of Ukraine. The Swedish government has decided that the Armed Forces will receive increased financial grants and that the organization will be expanded in personnel. In the future, a large part of the Army's units will all consist of part-time personnel, ie reserve officers, part-time soldiers and conscripts. These categories of personnel both need to maintain their skills and develop to fill their place in the war organization. At present, when reserve officers are called up for duty in connection with education or training, participation is voluntary. The Armed Forces' perception is that almost half of Sweden's approximately 6,800 reserve officers have not served since 2014. The purpose of the study is to explore what motivates and what is perceived as aggravating or purely hindering factors for service for the reserve officers in Skaraborg regiment. The study's focus is on what engages them to serve in the Armed Forces and what can increase their motivation. The study is based on interviews. The collected empirics are analyzed with Grounded theory. The analysis combines two different theories of motivation to understand the situation of reserve officers. Amitai Etzioni's Compliance theory, a theory on power, involvement, and their correlates in organizations, is combined with Herzberg, Mausner and Snyderman's The motivation to work, a theory of motivation in the workplace. The reserve officers perceive the service as fundamentally motivating and the Armed Forces is recommended to strengthen the relationship with their employees and benefit from the spirit in the unit. The study has identified five areas that mainly affects the reserve officers' engagement: the military environment, communication, interaction, rules, and pay and compensation. The special environment that arises in the Armed Forces is the single most motivating factor for service. It is an environment that the interviewed reserve officers thrive in, an environment that they also state is difficult to find anywhere else. The environment consists of the unique combination of military context, the relationship with colleagues and the feeling of belonging to something bigger.

Electricity providers has a growing interest in moving towards Renewable Energy Sources (RES) for power generation due to their attractive features. This has caused phasing out of coal, oil and nuclear power plants which use large synchronous generators for power production. These large rotational masses provide inertia to the electricity grid which compensate the sudden frequency instabilities of the grid. Therefore, lowering the system inertia opens up to frequency instabilities in the electricity grid.  As a solution for the lower system inertia, the concept of Fast Frequency Reserve (FFR) has been introduced. The timeframe of primary generation reserves can be too slow in case of a sudden frequency instability. Amongst the energy sources that can be used for FFR, this thesis work explores the possibility of a Battery Energy Storage System (BESS) to be used in FFR. To accomplish this objective, a total BESS system including power electronic converters for integration to the grid is designed in this work. The software of choice for simulation is Matlab/Simulink.  This work uses a hybrid battery model proposed by previous research which is a combination of runtime model and Thevenin model. A bidirectional Buck-Boost converter integrated with a current controller has been used as the DC-DC converter. An outer voltage control loop integrated with the inverter dq current controller has been used to connect the BESS to the gird. The function of each subsystem is observed to verify their functionality. The hybrid battery model is tested by comparing results with the battery model available in Simulink. Finally, power delivery to grid under FFR activation requirements is observed.  Results show that the hybrid battery model is a good approximation to represent a real battery cell in electrical grid applications. The simulation time can be reduced by replacing the series battery cell configuration used in this work with the Simulink battery model. The power delivery to the grid shows BESS is a reliable energy resource that can be used for FFR.

Seminaturliga gräsmarker är en av Europas artrikaste, men mest hotade naturmiljöer. För att rädda och bevara dess arter finns flera olika legala naturskydd med särskilda skötselkrav. Denna studie undersöker om skyddsstatusen gör någon skillnad för mångfalden bland kärlväxter på seminaturliga staggräsmarker. Undersökningen är liten, men trots få replikat pekar analysresultaten ändå på samma tendenser som andra och större studiers resultat. Analyser av insamlade data visar att de skyddade naturområdena har en rikare mångfald av kärlväxter i allmänhet och av naturvårdsarter i synnerhet. Resultaten visar att skötseln av den seminaturliga gräsmarken har betydelse då de skyddade gräsmarkerna har fler hävdgynnade arter. Någon särskild näringspåverkan kan inte påvisas i denna studie, vare sig i skyddade eller icke skyddade områden. De sammanlagda analyserna indikerar att det framför allt är naturskyddet och dess skötselkrav som påverkar mångfalden och artsammansättningen. Upphör hävd som slåtter och bete på seminaturliga gräsmarker leder det till minskad kärlväxtflora, i synnerhet av hävdgynnade arter och slutsatsen blir därmed att legalt skyddade naturmiljöer behövs för att rädda och bevara både hotade arter och hotad mångfald. / Semi-natural grasslands are one of Europe's most species-rich, but most threatened natural environments. In order to save and preserve species, there are several different legal nature reserves with special maintenance requirements. This study investigates whether conservation status makes a difference for the diversity of vascular plants in semi-natural grasslands. The study is very small, but despite few replicates, the analysis results still show the same tendencies as other and larger studies have done. Analysis of collected data shows that the protected natural areas have a richer diversity of vascular plants in general and of conservation indicator species in particular. The analysis results show that the management of the semi-natural grassland is important as the protected grasslands contain more species that are depended on mowing and grazing. The combined analyzes indicate that it is above all nature conservation and its management requirements that affect the diversity and species composition. Cessation of mowing and grazing on semi-natural grasslands leads to a reduction in vascular plant flora, especially species that are dependen on mowing and grazing, and the conclusion is thus that legally protected natural environments are needed to save and preserve both threatened species and threatened diversity.

Objectives: The purpose of this thesis is to explore the associations between childhood cognitive abilities assessed at age 8 and health and socioeconomic outcomes at age 29-36 in extremely low birth weight survivors (ELBW, <1000g). Methods: Using data from the McMaster Extremely Low Birth Weight Cohort Study, Study 1 explores the influence of overall intelligence, fluid intelligence, and language abilities on the prevalence of lifetime major depressive disorder in ELBW survivors and normal birth weight comparison subjects. Study 2 examines the mediating role of overall intelligence, fluid intelligence, language abilities, quantitative reasoning, and academic achievement on the association between being born at ELBW and socioeconomic outcomes at age 29-36. The final study examines the moderating role of childhood cognitive functioning on links between postnatal psychosocial adversity and adult personal earnings in ELBW survivors. Results: Results from Study 1 suggest that childhood cognitive abilities do not influence the onset of major depressive disorder in ELBW survivors, but are protective against depression in normal birth weight individuals. Study 2 suggests that childhood cognitive abilities partially mediate the association between being born at ELBW and income attainment in adulthood, but not full time employment. Further, Study 2 suggests that this association is stronger in ELBW survivors who have neurosensory impairments. Results of Study 3 suggest that enhanced childhood cognitive functioning is not protective against postnatal psychological adversity in influencing income attainment, as those ELBW survivors with higher childhood intelligence and who suffered psychological adversity reported lower annual income at age 30. Conclusions: This thesis suggests that overall and specific cognitive abilities significantly influence adult outcomes in ELBW survivors and normal birth weight individuals. However, while cognitive reserve may not be protective against psychological adversity in ELBW survivors, early cognitive abilities are a critical indicator of socioeconomic attainment in this vulnerable population. / Thesis / Master of Science (MSc) / The following thesis explores the predictive role of childhood cognitive abilities on adult health and socioeconomic outcomes in extremely low birth weight survivors at age 29-36. Study 1 explores the influence of overall intelligence, fluid intelligence, and language abilities assessed at age 8 on the prevalence of lifetime major depressive disorder in extremely low birth weight survivors and normal birth weight comparison participants. Study 2 examines the mediating role of overall intelligence, fluid intelligence, language abilities, quantitative reasoning, and academic achievement on the association between being born at extremely low birth weight and socioeconomic outcomes at age 29-36. The final study examines the moderating role of childhood cognition on the association between postnatal psychosocial adversity and personal income attainment at age 30 in extremely low birth weight survivors. Overall, this body of work suggests that childhood cognitive abilities are an important contributor to adult outcomes in preterm survivors.

This dissertation considers the political behaviour of youth in Whitefish River First Nation. This small Ojibway community located near Sudbury, Ontario is used as a case study to inquire into the political experiences, attitudes and behaviour of youth. Rooted in Community-Based Research and Indigenous Research Principles, conversations were carried out in a circle-method referred to as Discussion Circles to assess the political behaviour of youth between the ages of 16 and 25. While this study is heavily qualitative-focused, it includes some quantitative components. These include a youth political participation questionnaire and electoral participation data for Whitefish River First nation in federal, provincial and band elections. Results demonstrate that the youth have a unique experience of politics defined by their identities, community and relationships. Their political behaviour is complex and nuanced. While they may not participate in conventional political activities, they are heavily involved in activities that are rooted in their culture and traditions. The community overall is democratically healthy and tends to participate widely in federal and provincial elections. Youth are for the most part satisfied with their lives in the community, but there are significant challenges due to the consequences of colonialism. Many of these implications affect their political behaviour. / Thesis / Master of Arts (MA)