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Mental toughness in cricketSteele, Gale Ivan 11 1900 (has links)
Mental toughness is accepted to be an important component of sporting performance, especially so in the domain of cricket. It has been called many names, such as Big Match Temperament, bottle, and mettle and it is widely believed that it plays a role in how successful a cricketer may be, although very difficult to define and explain. James Loehr described it as one’s ability to consistently perform to the upper limit of your talent and skill and numerous researchers have since tried to define the construct based on more empirical research. This research project consists of three articles on mental toughness. The first focuses on the consideration of extra-personal influences on the development and implementation of mental toughness programmes. The second focuses on examining the psychometric properties of the paper-and-pencil versions of the Sports Mental Toughness Questionnaire (SMTQ) and the Psychological Performance Inventory-Alternative (PPI-A). The third examines the differences in the demographic characteristics of a sample of cricketers on the online versions of the SMTQ and the PPI-A. The results suggest that extra-personal influences are exceptionally important in the development and implementation of mental toughness programmes for school level cricketers, especially motivational climate and social support. While the PPI-A and the SMTQ displayed some promising psychometric properties in the current study, researchers should apply these mental toughness inventories with circumspection, taking into account questions regarding dimensionality, item formulation and variation in sample characteristics (e.g., age and sporting code), until more research can be conducted using these inventories with larger and more varied samples and the understanding of the mental toughness construct improves. The examination of the demographic differences on scores of the SMTQ and PPI-A revealed inconclusive results on age, sex, and ethnicity, while competitive level was the only distinguishing characteristic in which respondents at high levels produced higher mental toughness scores. The three studies comprising this “by articles” format PHD dissertation will be referred to as Article 1, Article 2, and Article 3 and can be found in Chapters, 2, 3, and 4 respectively. / Psychology / D.Phil. (Psychology)
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Untersuchungen zur Diskusverlagerung ohne Reposition am KiefergelenkPeroz, Ingrid 24 March 2004 (has links)
Die vorliegende Arbeit fasst 4 Studien zusammen, die konservative Behandlungsstrategien und Folgeerscheinungen an Kiefergelenken mit bestehender Diskusverlagerung (DV) ohne Reposition evaluieren. Studie 1 beurteilt die Therapie mit Äquilibrierungsschienen in Form einer Anwendungsbeobachtung. Die Schmerzsymptomatik und die Kieferöffnungsweite werden über einen Beobachtungszeitraum von 13 Monaten positiv beeinflusst. Studie 2 zeigt als randomisierte, kontrollierte Doppelblindstudie, dass sich die Symptomatik der DV ohne Reposition sowie der aktivierten Arthrose während eines Beobachtungszeitraums von 4 Monaten signifikant verbessert, unabhängig von der durchgeführten Therapie bzw. der Behandlung mit einem Placebogerät. Somit erzielt die Pulsierende Signaltherapie keinen spezifischen therapeutischen Effekt. Die Studie 3 beurteilt die Kaueffektivität bei vorliegender DV ohne Reposition im Vergleich zu einer Kontrollgruppe. Die Kaueffektivität nimmt in Abhängigkeit von der Dauer des Krankheitsbildes deutlich zu, erreicht jedoch nicht die Effizienz der gesunden Vergleichsgruppe. Die Studie 4 stellt eine MRT-gestützte Nachuntersuchung von Patienten mit DV ohne Reposition dar. Das Krankheitsbild geht mit deutlichen degenerativen Veränderungen der Gelenkstrukturen einher, die sich aber über einen Beobachtungszeitraum von ca. 2 Jahren hinweg nicht signifikant verändern. Entzündungszeichen nehmen jedoch signifikant ab und die Translationsbewegung der Kondylen verbessert sich. Die DV ohne Reposition kann somit als Krankheitsbild mit morphologischen Veränderungen und funktionellen Beeinträchtigungen gewertet werden, dessen subjektive Beschwerden sich auch ohne Intervention verbessern. Morphologische Veränderungen unterliegen sich selbst limitierenden Adaptationsmechanismen. / This work presents four studies dealing with disk displacement without reduction, its treatment and long-term effects. Study 1 evaluates the treatment effects of stabilization splints. The study has a prospective follow-up design. Thirteen months after the baseline examination pain relieves and mouth opening reached a significant larger extend. Study 2 is randomised controlled and double blinded and evaluates pulsed electromagnetic fields (PEMF) as a new conservative treatment method. After a period of 4 months the pain relieves significantly and mouth opening is significantly larger in patients with anterior disk displacement or activated arthrosis, independent to active or mock treatment. PST has no specific effect on disk displacement without reduction or activated arthrosis. Study 3 tests the chewing efficiency of patients with disk displacement without reduction in comparison to a control trial. The chewing efficiency improves according to the time since onset of the disorder but is nevertheless reduced compared to a control group without TMJ-disorders. Study 4 is a MRI-controlled study, evaluating morphologic changements. Over an average time of 2 years no significant ongoing of degenerative changements accur, only high signal areas disappear and the translation of the condyle improves significantly. Anterior disk displacement is therefore a TMJ-disorder accompanied by limitation of joint function and degenerative changements of joint structures, which improve without treatment and can be interpreted as a self limiting adaptative process.
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Control of transmission system power flowsKreikebaum, Frank Karl 13 January 2014 (has links)
Power flow (PF) control can increase the utilization of the transmission system and connect lower cost generation with load. While PF controllers have demonstrated the ability to realize dynamic PF control for more than 25 years, PF control has been sparsely implemented.
This research re-examines PF control in light of the recent development of fractionally-rated PF controllers and the incremental power flow (IPF) control concept. IPF control is the transfer of an incremental quantity of power from a specified source bus to specified destination bus along a specified path without influencing power flows on circuits outside of the path.
The objectives of the research are to develop power system operation and planning methods compatible with IPF control, test the technical viability of IPF control, develop transmission planning frameworks leveraging PF and IPF control, develop power system operation and planning tools compatible with PF control, and quantify the impacts of PF and IPF control on multi-decade transmission planning.
The results suggest that planning and operation of the power system are feasible with PF controllers and may lead to cost savings. The proposed planning frameworks may incent transmission investment and be compatible with the existing transmission planning process. If the results of the planning tool demonstration scale to the national level, the annual savings in electricity expenditures would be $13 billion per year (2010$). The proposed incremental packetized energy concept may facilitate a reduction in the environmental impact of energy consumption and lead to additional cost savings.
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