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Vibration suppression of beams traversed by moving loads, using optimal Tuned-Mass-Damper (TMD) systems, is investigated. This study is performed on two different geometrical shapes of the beam, namely, uniform homogenous straight beam, and the uniform homogenous curved beam. Initially, three different models of the moving load on a straight beam were developed using the APDL coding in ANSYS©, a commercially available software. Results obtained from the numerical simulation of either a single moving load or a moving mass on the straight beam were compared and validated with those reported in literature. A comprehensive parameter sensitivity analysis was carried out on the beam traversed by moving load with and without the presence of random base excitation and the effects of different beam parameters on the dynamic response of the system were closely examined. Vehicles travelling on suspension bridges induce undesirable vibration, which must be suppressed to a great extent. A half-car planar model moving on a straight beam is considered to study the suppression of vibration and parameter optimization. Attempt is made to design an optimal TMD system to suppress the induced vibration of the bridge due to the moving vehicle, considerably. Furthermore, the effect of non-symmetrical and side-way motion of vehicles on bridges has been considered when both the torsional and flexural vibrations of the bridge-vehicle have been present. Optimum values of the double-acting TMDs parameters have been found to suppress the combined flexural and torsional vibrations of the supporting beam structure. Similar work has been carried out on a uniform homogenous curved beam traversed by either a moving load or a half-car planner model. The effects of the beam curvature angle and the type of loading are closely studied. Optimum values of the two TMDs were obtained to suppress the combined flexural and torsional vibrations of bridges traversed by traveling vehicles. / UOIT

Increasing power density of switch mode power supplies, by increasing their switching frequency has becoming a challenging obstacle for EMI mitigation. The passive EMI suppression technique has always been the primary solution to fulfill the EMC requirement in terms of conducted emission limits. However, the call for stringent power supplies specifications renders the passive techniques less desirable, due to their increasing size and power losses. In other words, the greater the power density of the converter, the bigger the passive filter. Other suppression techniques such as the spread spectrum frequency modulation (SSFM), and soft switching, prove to have less performance and much complex to implement. The active analog EMI filters provide the basic noise suppression technique; however, their performance is dramatically impeded at higher frequency. This solution requires an additional small size passive filter to complete the EMC spectrum for conducted emissions. Digital active filtering techniques offer advantages of flexibility, fewer external components and reduced overall size and power losses as compared to conventional passive filtering techniques. In this thesis DSP-based and FPGA-based EMI control techniques to mitigate the conducted emissions of switch mode power converters are proposed. These techniques are implemented in-lieu of the passive filtering techniques, by keeping equal or better performance. Moreover, these solutions can be configured as a stand-alone or integrated into the converter digital controller algorithm. Finally, the proposed solutions are implemented into three types of power converters, namely, a AC-DC power factor corrected converter, DC-AC micro-inverter for Photovoltaic application, and DC-DC for Electric Vehicle (EV) battery charger. Analytical, simulation and experimental results are provided to verify the proposed solutions. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2011-11-07 10:48:49.191

The Harry Potter novels written by J.K Rowling have been popular since the first book was released in 1997. Rowling has written seven books about Harry and the first four together with the Swedish National Agency for Education constitute the primary sources of this essay. The essay discusses how these supposed children’s’ novels can be used to construct a lesson for students in the Swedish upper secondary classroom. The lesson plan created is based on the analysis of the possible themes of the novels using Postcolonial and Marxist critical perspectives. The theories are used to show how discrimination and suppression can be seen in the Harry Potter novels. Previous research has shown that the occurrences in Harry Potter is similar to the occurrences happening in the real world and the lesson plan is created to compare these fictional happenings with the ones happening in our real society. The lesson plan constructed consequently focuses on how the Harry Potter novels can be used to discuss discrimination and suppression takes place in English speaking societies as required by the rules and guidelines provided by the Swedish National Agency for Education.

Syftet med studien var att verifiera sambandet mellan personlighetsdrag, affekt och emotionsreglering. Det undersöktes om hur specifika personlighetsdrag kan predicera användning av emotionsreglering. Utgångspunkten var tidigare forskning som visar korrelationer mellan dessa tre variabler. Undersökningen utfördes online och sammanlagt deltog 47 personer. Extraversion i sig visade sig kunna predicera både användning av Omvärdering och upplevelse av positiv affekt, medan Neuroticism bara verkar kunna predicera negativ affekt. Multipelregressionsanalysen visade att Öppenhet och Vänlighet leder till ökning användning av Omvärdering. Ökningen i Öppenhet var också relaterad till ökning av positiv affekt, samtidigt som Extraversion var relaterad till minskad användning av Supression.  Utöver det hittades positiva korrelationer mellan Supression och negativ affekt samt Omvärdering och positiv affekt, och negativt samband med vice versa.

Positive affect, which has been broken down into four lower-level facets (i.e., joviality, attentiveness, self-assurance, serenity), has demonstrated numerous ties to physical and mental health. The experience of positive affect can be regulated by emotion regulation strategies. However, few studies have assessed their relationship, and no studies have examined the relationship using the lower level facets of positive affect. The link between positive affect and emotion regulation may be of particular importance for individuals at increased risk for bipolar disorder, as both are disrupted in individuals with the condition. The aim of the present study was to examine the relationship between positive affect and emotion regulation while also exploring whether risk for bipolar disorder moderated their relationship. Undergraduates (N = 155) completed measures of emotion regulation, affect, and bipolar disorder risk at baseline. Using ecological momentary assessment (EMA), participants completed surveys 3 times a day for 7 days. Hierarchical linear models were estimated and revealed significant effects between certain baseline emotion regulation tendencies (experiential avoidance/ psychological inflexibility, rumination, behavioral social avoidance) and daily positive affect facets as well as between daily emotion regulation use (i.e., reappraisal, acceptance, reflection, savoring, mindfulness social support, suppression, rumination, procrastination) and daily positive affect facets. Bipolar disorder risk was not found to moderate the relationship. Findings support the use of strategies emphasized in evidence-based treatments and highlight the importance of daily practice of emotion regulation skills.

Recentemente demonstrou-se o papel de células T produtoras de IL-17 na patogênese da esclerosa múltipla e de seu modelo, a EAE. Através da produção desta e de outras citocinas, a população chamada Th17 promove o rompimento da barreira hematoencefálica e a conseqüente infiltração de células patogênicas para dentro do SNC. Nesse contexto, em nosso trabalho utilizamos o fenômeno da tolerância oral para avaliar a capacidade deste em suprimir a resposta imune durante o modelo de EAE, mais especificamente as células Th17. Nossos dados demonstram uma diminuição de IL-17 tanto na periferia como no SNC dos animais tolerados. Além disso, detectamos menos CCL2 e IL-6 em células extraídas do CNS dia 10 pós-imunização. Não observarmos diferença na produção de IL-4,5,10, 13, IL-12p70, TNF-<font face=\"symbol\">a, e IFN-<font face=\"symbol\">g entre os grupos. Em suma, nossos resultados mostram que o fenômeno da tolerância oral é capaz de suprimir parâmetros de EAE devido a uma menor capacidade linfoproliferativa associada a uma supressão de células patogênicas Th17 tanto na periferia como no SNC. / It has recently been shown the role of IL-17 secreting cells on the pathogenesis of multiple sclerosis and also in its model, EAE. Due to the secretion of this and other cytokines, the population so called Th17, promotes the disruption of the blood-brain barrier and the following infiltration of pathogenic cells into the CNS. In this context, in our work we used the oral tolerance phenomenon to evaluate its supressive capacity, more specifically over the Th17 cells. We showed that oral tolerated mice has a diminished production of IL-17 both in the periphery and in the CNS. Futhermore, we detected lower levels of CCL2 and IL-6 also from brain and spinal cord extracted mononucear cells at day 10th post-immunization. We were not able to detect differences on IL-4,5,10, 13, IL-12p70, TNF-<font face=\"symbol\">a, e IFN-<font face=\"symbol\">g between the groups. Thus, our results show that the oral tolerance phenomenon suppresses EAE findings, mainly due to a lower lymphoprolipherative response associated to a supression over the expansion of Th17 pathogenic T cells both in the periphery and inside the CNS.

A supressão condicionada é definida como a redução na taxa de resposta operante diante de um estímulo que foi previamente pareado com um evento aversivo inevitável e independente do comportamento do sujeito. A linha de base na qual se sobrepõe os pareamentos tem sido apontada como uma das variáveis críticas na determinação do efeito supressivo. Portanto, o objetivo desse trabalho foi verificar se esquemas de reforçamento contingentes à variabilidade ou à repetição do comportamento seriam igualmente sensíveis ao procedimento de supressão condicionada. Ratos foram divididos em dois grupos (n=6), denominados Variabilidade (VAR) e Repetição (REP), que diferiram apenas quanto ao esquema de reforçamento da linha de base. Os sujeitos do grupo VAR foram submetidos a uma contingência que exigia que eles emitissem diferentes seqüências de quatro respostas de pressão a duas barras (esquema RDF). Já os sujeitos do grupo REP foram reforçados por emitir uma única seqüência (seqüência EEEE). Depois de 25 sessões sob esses esquemas, foram introduzidos os pareamentos aversivos, que consistiram na apresentação de duas luzes de 12 V, por 20 s, localizadas em cima de cada barra, que foram regularmente seguidas por choques de 0,8 mA por 0,5 s. Os resultados indicaram que os dois grupos foram sensíveis aos pareamentos CS-US, mostrando queda na taxa de resposta operante frente ao estímulo condicionado. Embora todos os sujeitos tenham apresentado forte efeito supressivo, a supressão foi mais acentuada no Grupo REP. No entanto, as diferenças obtidas nas razões de supressão dos dois grupos foram pequenas considerando a magnitude das diferenças entre as contingências de reforçamento utilizadas, que selecionavam padrões opostos em relação à variabilidade do comportamento. Discutiu-se que alguns parâmetros utilizados poderiam explicar a pequena diferença obtida aqui em comparação com os estudos da literatura. Os resultados apontaram ainda que os padrões de variar e repetir não foram afetados pela exposição ao US aversivo, mantendo-se no final do experimento os mesmos níveis da linha de base. Portanto, os dados sugerem que a variabilidade operante pode coexistir com contingências aversivas, ampliando o potencial de análise da variação do comportamento, que usualmente é investigada apenas com reforço positivo / Conditioned suppression is defined as a decrease in the rate of a positively reinforced response during a stimulus which precedes an unavoidable shock. The reinforcement schedule used to maintain the baseline performance is an important variable in determining the degree of suppression. Therefore, the purpose of the present study was to compare the effects of different reinforcement schedules that selected behavioral variation or repetition in the conditioned suppression procedure. Rats were divided into two groups (n=6), named Variability (VAR) and Repetition (REP), that differed from each other in relation to the reinforcement schedules used to maintain the baseline. In VAR Group, rats were rewarded for variable response sequences. In REP Group, rats were rewarded for repeating a single LLLL sequence. After 25 sessions in these schedules, periods of light (20 sec.) were terminated with a brief, unavoidable shock (0.8 mA/ 0.5 sec.) for the two groups. The results indicated that the rate of operant response of all subjects decrease during the CS. Therefore all subjects showed strong suppression, the effect was more severe in REP Group. However, the difference obtained was small considering the differences in the reinforcement schedules that selected opposite performances related to behavioral variation. It was discussed that some parameters of this experiment could explain the small difference obtained here in contrast with previous studies. The results also showed that variation and repetition sequences are not affected by the aversive US. Thus, the data suggest that operant variability could be maintained in aversive contingencies

Recentemente demonstrou-se o papel de células T produtoras de IL-17 na patogênese da esclerosa múltipla e de seu modelo, a EAE. Através da produção desta e de outras citocinas, a população chamada Th17 promove o rompimento da barreira hematoencefálica e a conseqüente infiltração de células patogênicas para dentro do SNC. Nesse contexto, em nosso trabalho utilizamos o fenômeno da tolerância oral para avaliar a capacidade deste em suprimir a resposta imune durante o modelo de EAE, mais especificamente as células Th17. Nossos dados demonstram uma diminuição de IL-17 tanto na periferia como no SNC dos animais tolerados. Além disso, detectamos menos CCL2 e IL-6 em células extraídas do CNS dia 10 pós-imunização. Não observarmos diferença na produção de IL-4,5,10, 13, IL-12p70, TNF-<font face=\"symbol\">a, e IFN-<font face=\"symbol\">g entre os grupos. Em suma, nossos resultados mostram que o fenômeno da tolerância oral é capaz de suprimir parâmetros de EAE devido a uma menor capacidade linfoproliferativa associada a uma supressão de células patogênicas Th17 tanto na periferia como no SNC. / It has recently been shown the role of IL-17 secreting cells on the pathogenesis of multiple sclerosis and also in its model, EAE. Due to the secretion of this and other cytokines, the population so called Th17, promotes the disruption of the blood-brain barrier and the following infiltration of pathogenic cells into the CNS. In this context, in our work we used the oral tolerance phenomenon to evaluate its supressive capacity, more specifically over the Th17 cells. We showed that oral tolerated mice has a diminished production of IL-17 both in the periphery and in the CNS. Futhermore, we detected lower levels of CCL2 and IL-6 also from brain and spinal cord extracted mononucear cells at day 10th post-immunization. We were not able to detect differences on IL-4,5,10, 13, IL-12p70, TNF-<font face=\"symbol\">a, e IFN-<font face=\"symbol\">g between the groups. Thus, our results show that the oral tolerance phenomenon suppresses EAE findings, mainly due to a lower lymphoprolipherative response associated to a supression over the expansion of Th17 pathogenic T cells both in the periphery and inside the CNS.