This thesis is an historical analysis of the phenomenon of piracy in the ancient world from the Bronze Age to the Arab conquests. It is based on detailed examination and discussion of the ancient sources. There is a short introduction (Part One) which establishes the scope of the enquiry, defines the subject and surveys modern scholarly literature. Part Two (The Image of Ancient Piracy) consists of a study of the Greek and Latin vocabulary for piracy, and six separate studies of Classical literature, from Homer to the fourth century A.D. These studies analyze the development of the literary image of pirates and piracy, from the ambivalent attitude of the Homeric poems, to the wholly negative presentation of pirates and piracy found in the works of later writers. Part Three (War and Piracy) analyzes the early similarity between warfare and piracy, the gradual emergence of distinctions between the two, warfare as a promoter of piracy, and the involvement of pirates in warfare. Part Four (Trade and Piracy) is an analysis of the relationship between piracy and various forms of trade. The importance of piracy as both a contributor and a threat to long-distance maritime trade is analyzed, as well as the involvement of pirates in the slave trade. The link between trade and the suppression of piracy is also discussed. Part Five (The Suppression of Piracy) examines in detail attempts to suppress piracy from the Classical period to the end of the Roman Empire. Emphasis is laid upon the practical and political implications of suppression, and the relative ineffectiveness of most measures until the Late Republic and Early Principate, when piracy was suppressed with considerable success. There follows a brief statement of the general conclusions (Part Six) and suggestions for further research. One map and a bibliography are included.

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Many space vehicles have been launched with large flexible components such as booms and solar panels. These large space structures (LSSs) have the potential to make attitude control unstable due to their lightly damped vibration. These vibrations can be controlled using a collection of control moment gyros (CMGs). CMGs consist of a spinning wheel in gimbals and produce a torque when the orientation of the wheel is changed. This study investigates the optimal distribution of these CMGs on LSSs for vibration suppression. The investigation considers a beam and a plate structure with evenly placed CMGs. The optimization allocates the amount of stored angular momentum possessed by these CMGs according to a cost function dependent on how quickly vibration motions are damped and how much control effort is exerted. The optimization results are presented and their effect on the motions of the beam and plate are investigated.

Many space vehicles have been launched with large flexible components such as booms and solar panels. These large space structures (LSSs) have the potential to make attitude control unstable due to their lightly damped vibration. These vibrations can be controlled using a collection of control moment gyros (CMGs). CMGs consist of a spinning wheel in gimbals and produce a torque when the orientation of the wheel is changed. This study investigates the optimal distribution of these CMGs on LSSs for vibration suppression. The investigation considers a beam and a plate structure with evenly placed CMGs. The optimization allocates the amount of stored angular momentum possessed by these CMGs according to a cost function dependent on how quickly vibration motions are damped and how much control effort is exerted. The optimization results are presented and their effect on the motions of the beam and plate are investigated.

Full-scale experiments are conducted to study the effects of different water-based indirect and combination initial attack methods on the compartment environment and firefighter during compartment fire suppression, with an aim toward improving manual fire suppression effectiveness and firefighter safety. Hot layer temperatures typical of room fire conditions are developed in the test compartment using wood cribs. Five suppression methods including straight stream, penciling, continuous wide and narrow fog, and a wide angle burst method are examined for two different spray angles and nozzle pressures. Temperatures, heat flux, gas velocity, and gas concentrations are monitored for the duration of each experiment in the fire compartment, along with temperatures and gas concentrations in the area of the firefighter, just outside the compartment. Realistic fire conditions are repeatedly established in the test compartment, with each fuel load allowing up to nine suppression applications per fire. The repeatability of the compartment temperatures are demonstrated by the consistent hot layer temperature stratification in the room, along with the uniformity of the hot layer throughout a test, and the consistency of the temperature from test to test. The repeatability of each suppression method is also demonstrated by comparing results of compartment cooling achieved in repeat tests. Differences in average compartment temperature before and during suppression indicate that penciling tactics provide little cooling of the compartment. In narrow fog attacks, the hot layer is pushed toward the floor, resulting in increased temperatures in the lower layer, generally an undesired result. Wide angle fog methods may have greater impact on compartment temperature as compared to straight stream or narrow fog methods, however, they also result in large increases in temperature at the firefighter. Wide angle burst tactics less effectively cool the compartment gases than continuous methods, but also lead to less impact on the firefighter. Greater numbers of bursts increase cooling of the compartment, but at the expense of increased impact on the firefighter. Including impact on the firefighter, continuous straight stream methods, at a nozzle discharge pressure of 700 kPa and aimed to the top of the rear compartment wall, appear the best choice for initial attack on the fire developed in these experiments. Due to variability between real fire scenarios and experiments such as these, significantly more study of the various suppression tactics is required before the most effective methods of suppression can be determined for a given set of fire scenarios.

Thesis (Ph.D.) - University of St Andrews, October 2008.

Thought suppression is the attempted removal of unwanted thoughts. A plethora of previous research suggests that thought suppression is ineffective and possibly even counterproductive. However, the psychological processes involved in suppression are still underspecified. The current thesis aimed to examine the processes involved in thought suppression and to provide alternative techniques that may be more effective in the management of unwanted thoughts. To that end, Chapters 2 and 3 of the current thesis investigated the two key phenomena in the thought suppression literature, the immediate enhancement and rebound effects. Results from Experiments 1-4 indicated that participants, for the most part, found it difficult to suppress their thoughts during a five minute suppression phase, and also tended to have the unwanted thought re-emerge in a five minute phase following suppression, providing evidence for both the immediate enhancement and rebound effects. Chapter 4 (Experiment 5) provided a model of the immediate enhancement and rebound effects in terms of derived stimulus relations. The findings suggested that thought suppression attempts are ineffective due to the large number of intended and unintended environmental reminders. Experiments 6(a) and 6(b) extended on Experiment 5 by demonstrating how those relations might affect overt behaviour. Finally, Chapter 5 aimed to compare thought suppression with alternative strategies for dealing with unwanted thoughts. Acceptance and Commitment Therapy (ACT) was designed to undermine the negative behavioural consequences of derived stimulus relations. Experiments 7, 8 and 9 compared thought suppression with two components of the ACT model (i.e., mindfulness and defusion). The findings indicated, across both self report and behavioural measures, that the ACT techniques provided useful alternatives to thought suppression. In conclusion, the current thesis provides a behavioural model of the counterproductive nature of thought suppression whilst providing favourable evidence of alternative methods in the management of unwanted thoughts.

La RMN à haut champ, basée sur des aimants supraconducteurs, est caractérisée par une instrumentation onéreuse et encombrante qui limite son utilisation dans les environnements de production. Le récent renouveau des aimants permanents a engendré des spectromètres RMN de paillasse qui permettent la réalisation d’expériences RMN directement sous la hotte du chimiste. L’objectif de cette thèse est d’améliorer la performance analytique de ces nouveaux spectromètres à bas champ. Dans cette optique, nous avons implémenté pour la première fois la RMN 2D Ultrarapide (UF) ainsi que des méthodes modernes de suppression du signal du solvant sur un spectromètre de paillasse opérant à 43 MHz équipé d’une bobine de gradient de champ magnétique. Suite à plusieurs optimisations, la RMN 2D UF à bas champ délivre des spectres 2D en un temps fortement réduit de qualité tout à fait intéressante. En parallèle, le développement des méthodes de suppressions permet dorénavant d’appréhender l’utilisation de solvant non-deutérés sur des échantillons statiques ou en flux. Ces travaux ont débouché sur de nouvelles opportunités pour la RMN à bas champ. Plusieurs suivis de réactions, réalisés en ligne et en temps réel, ont été menés à bien sur diverses réactions comme le couplage de Heck-Matsuda, la neutralisation de mimes de gaz moutardes ou encore la synthèse d’un composé naturel par chimie en flux. Par ailleurs, la RMN 2D UF à bas champ a été appliquée avec succès pour discriminer des huiles alimentaires en fonction de leurs origines botaniques. Cette méthodologie 2D, compatible avec des analyses à haut débit, démontre une amélioration notable par rapport à la RMN 1D. / High-field NMR based on superconducting magnets involves an expensive and bulky equipment, which has hampered the use of NMR in harsh environments. A new generation of benchtop NMR spectrometers, compact and cryogen free, has brought NMR spectroscopy under the chemist’s fume-hood and as close as possible to production sites. The driving force of this PhD project is to improve the analytical performance of these benchtop NMR systems. We report here the first implementation of Ultrafast (UF) 2D NMR- a method yielding 2D NMR spectra in a single scan- as well as modern gradient-based solvent suppression methods on a 43 MHz benchtop spectrometer, including a B0-gradient coil. Substantial optimizations have led to UF experiments at low-field (LF) with a reasonable performance while the acquisition duration is reduced by one order of magnitude. Then, the presence of non-deuterated solvents –commonly used in LF NMR– has been tackled by the development of suppression methods both in static and flowing conditions. This methodological effort has opened new opportunities for benchtop NMR applications. Several on- and in-line real-time monitorings have been performed on different types of chemical reactions: Heck-Matsuda coupling reaction, oxidative neutralization of mustard-gas simulants or even the synthesis of a natural product in flow-chemistry. Besides applications to process monitoring, UF 2D NMR at 43 MHz has been successfully applied to discriminate the botanical origins of a panel of edible oils. This fast 2D approach has provided a better classification than standard 1D experiments while remaining compatible with high-throughput analysis.

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