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Underwater gliders are highly efficient, winged autonomous underwater vehicles that propel themselves by modifying their buoyancy and their center of mass. The center of mass is controlled by a set of servo-actuators which move one or more internal masses relative to the vehicle's frame. Underwater gliders are so efficient because they spend most of their time in stable, steady motion, expending control energy only when changing their equilibrium state. Motion control thus reduces to varying the parameters (buoyancy and center of mass) that affect the state of steady motion. These parameters are conventionally controlled through feedback, in response to measured errors in the state of motion, but one may also incorporate a feedforward component to speed convergence and improve performance. In this dissertation, first an approximate analytical expression for steady turning motion is derived by applying regular perturbation theory to a realistic vehicle model to develop a better understanding of underwater glider maneuverability, particularly with regard to turning motions. The analytical result, though approximate, is quite valuable because it gives better insight into the effect of parameters on vehicle motion and stability. Using these steady turn solutions, including the special case of wings level glides, one may construct feasible paths for the gliders to follow. Because the turning motion results are only approximate, however, and to compensate for model and environmental uncertainty, one must incorporate feedback to ensure convergent path following. This dissertation describes the development and numerical implementation of a feedforward/feedback motion control system intended to enhance locomotive efficiency by reducing the energy expended for guidance and control. It also presents analysis of the designed control system using slowly varying systems theory. The results provide (conservative) bounds on the rate at which the reference command (the desired state of motion) may be varied while still guaranteeing stability of the closed-loop system. Since the motion control system more effectively achieves and maintains steady motions, it is intrinsically efficient. The proposed control system enables speed, flight path angle, and turn rate, providing a mechanism for path following. The next step is to implement a guidance strategy, together with a path planning strategy, and one which continues to exploit the natural efficiency of this class of vehicle. The structure of the approximate solution for steady turning motion is such that, to first order in turn rate, the glider's horizontal component of motion matches that of "Dubins' car," a kinematic car with bounded turn rates. Dubins car is a classic example in the study of time-optimal control for mobile robots. For an underwater glider, one can relate time optimality to energy optimality. Specifically, for an underwater glider travelling at a constant speed and maximum flight efficiency (i.e., maximum lift-to-drag ratio), minimum time paths are minimum energy paths. Hence, energy-efficient paths can be obtained by generating sequences of steady wings-level and turning motions. These efficient paths can, in turn, be followed using the motion control system developed in this work. / Ph. D.

This thesis presents a greedy search algorithm for maneuver-based motion planning of agile vehicles. In maneuver-based motion planning, vehicle maneuvers are solved offline and saved in a library to be used during motion planning. From this library, a tree of possible vehicle states can be generated through the search space. A depth-first, library-based algorithm called AD-Lib is developed and used to quickly provide feasible trajectories along the tree. AD-Lib combines greedy search techniques with hill climbing and effective backtracking to guide the search process rapidly towards the goal. Using simulations of a four-thruster hovercraft, AD-Lib is compared to existing suboptimal search algorithms in both known and unknown environments with static obstacles. AD-Lib is shown to be faster than existing techniques, at the expense of increased path cost. The motion planning strategy of AD-Lib along with a switching controller is also tested in an environment with dynamic obstacles. / Master of Science

This study is intended to examine the star persona of French actor, Jean-Pierre Léaud. By inquiring into both the character on and off screen I have analysed the career and performances of an actor who has laid a significant mark on contemporary French cinema. Whilst Léaud’s nouvelle vague image has become an enduring symbol within French cinema, little is known about Léaud from written texts alone. Moreover, he has not been readily accepted as a star in the same way as many of his male contemporaries. Using star studies as a theoretical approach, I am exploring the various characters Léaud has incarnated on screen, his performances, and the strong relationships he has forged with various directors throughout his career in seeking to conceptualise his star image. Looking at Léaud the person and Léaud the actor I hope to establish wherein lies the mythology surrounding this unique actor. By looking at stardom and spectatorship theory, I have explored the ways in which we can perceive Léaud as actor and star. The central question to this is: how do subjectivity and spectatorship shape our perceptions of what makes a star? Underlying this question are the various ambiguities and sites of contradiction that make up his star image. In examining such contradictions I have taken Richard Dyer’s Stars and Edgar Morin’s Les Stars as a starting point. This leads to a consideration of Dyer’s formulation of “alternative or subversive types” (Dyer 1979: 52) together with questions of gender representations and sexuality. The types embodied by Léaud’s characters are not idealised males as seen in the star personae of Jean Gabin, Jean-Paul Belmondo, Alain Delon, and Gérard Depardieu among other French stars. Yet even within these more conventional star images, sites of contradiction are present that help qualify the ambiguities presented by Léaud’s star status. What is important here is Dyer’s notion that stars hold the capacity to bring together the ‘ordinary’ within sites of contradiction. This is presented by Léaud’s androgynous figure, the unlikely occupations undertaken by many of his characters, their awkward attempt to seduce women and subsequent unsatisfactory relationships, the concept of the flâneur, and a certain quirky comic side to these characters.

This thesis analyses the concept of the “Vietnam Syndrome” and its continuing manifestation in fictional American films produced after the 1991 Gulf War, with reference to depictions of the Vietnam, Gulf and Iraq Wars. Based on contemporary press reports as source material and critical analysis, it identifies the “Vietnam Syndrome” as a flexible and altering national psychological issue characterised initially as a simple aversion to military engagement, but which grew to include collective feelings of shame, guilt and a desire to rewrite history. The thesis argues that the “Syndrome” was not quashed by the victory of the Gulf War in 1991, as had been speculated at the time. Rather, the thesis argues that it was only temporarily displaced and continues to be an ingrained feature of the collective American psyche in current times. The argument is based on theories of collective memory, according to which social attitudes are expressed in cultural products such as films. The relationships between memory and history, and between memory and national identity are explored as two highly relevant branches of collective memory research. The first of these combines the theories of Bodnar (1992), Sturken (1997), Winter and Sivan (1999) and Wertsch (2002), among others, to define memory’s relationship with history and position in the present. The discussion of the relationship between memory and national identity describes the process by which memory is adopted into the national collective, based on the research of Schudson (1992) and Hall (1999). Consideration is given to the alternative theories of Comolli and Narboni (1992 [1969]), Hobsbawm and Ranger (1983) and Miller (2005) that propose a unified representation from a dominant ideology and of The Popular Memory Group (1982) who argue a counter-hegemonic popular memory. The thesis argues that both are insufficient to account for public memory, establishing a multi-sourced collective memory as the basis for its arguments, as described by Hynes (1999) and Wertsch (2002). Successive chapters provide a close analysis of films in relation to the “Vietnam Syndrome”. Each of the films shows the different approaches to the conflicts and ways the “Vietnam Syndrome” manifests itself. Chapter 3 provides a summary of Vietnam War films released prior to the main period focused upon in this thesis, in order to contextualise the post-Gulf War texts. Chapter 4 analyses Heaven and Earth (1993, Dir. Oliver Stone) as a revolutionary depiction of the Vietnam War from a Vietnamese depiction. Chapter 5 discusses The War (1994, Dir. Jon Avnet) as a late revisionist text. The focus of Chapter 6 is Apocalypse Now Redux (2001, Dir. Francis Ford Coppola), a revision of a vision, in which the additional scenes are analysed for their contribution to this later, more reflective version of the 1970s text Apocalypse Now. The last Vietnam film analysed, We Were Soldiers (2002, Dir. Randall Wallace), is the subject of Chapter 7 and is discussed with reference to post-September 11 American society and the dormant period of the “Vietnam Syndrome.” Chapter 8 brings the previous Vietnam War film analysis chapters together to form intermediate conclusions prior to the progression to Gulf War films. Chapter 9 provides a break in the film analysis chapters to consider the press coverage of the Gulf War, compared to that of Vietnam, paving the way for the following discussion of Gulf War films. Press coverage of the Gulf War influences the visual depiction of the Gulf War in both Three Kings (1999, Dir. David O’Russell) in Chapter 10 and Jarhead (2005, Dir. Sam Mendes) in Chapter 11. The reading of Three Kings also analyses the narrative as a metaphor for American concerns over the American-led coalition’s conduct during the conflict, while Chapter 11 argues the use of Vietnam War films as media templates (Kitzinger, 2000) in Jarhead. Finally, Chapter 13 brings the film analysis to a close by discussing the early representations of the Iraq War that have emerged in recent years, including: American Soldiers: A Day in Iraq (2005, Dir. Sidney J. Furie), Home of The Brave (2006, Dir. Irwin Winkler), Stop-Loss (2008, Dir. Kimberley Peirce), Lions For Lambs (2007, Dir. Robert Redford) Redacted (2008, Dir. Brian de Palma) and The Hurt Locker (2008, Dir. Kathryn Bigelow). The main, but not exclusive, features typifying the “Vietnam Syndrome” expressed through the films include: a reluctance to engage in or support foreign military intervention; use of “good war” and “bad war” discourse; signs of a collective national trauma of defeat; expressions of guilt for the consequences of American actions and failings of policy; attempts to restore the national self-image. This thesis concludes that the “Vietnam Syndrome” is still relevant to American society and that it is expressed through films in a variety of ways. It argues that the Vietnam War and the “Vietnam Syndrome” have become frames of reference for the discussion and representation of conflict and that the American collective psyche suffers a mixture of syndromes, some mutually enforcing and some contradictory, that are triggered by a variety of circumstances. The “Vietnam Syndrome” is identified as the most prolific of these and through its construction and circulation in media products, including cinema, this thesis argues it has become an umbrella term for the remnants of angst over Vietnam and new concerns over other conflicts.

This thesis takes as its starting point the fact that this period witnessed easily the highest and most consistent levels of indigenous feature film production in the history of Scottish film culture. By the end of the 1990s, many observers proposed that it was for the first time possible to talk about the existence of a 'Scottish cinema' and/or a 'Scottish film industry', where before only occasional Scottish films and/or Scottish filmmakers could be discerned. This thesis argues that the most important precipitant of Scottish cinema's unprecedented 1990s industrial expansion involved local filmmakers' pre-mediated, industrially aspirant adaptation of American cinematic precedents and working practices. The nature of this 'adaptation' was two-fold. On one hand, it was institutional, relating to the reformation and creation of the kind of financial, training and plant infrastructures which make feature production possible. On the other, it was creative, relating to the generic and aesthetic influences and reference points preferred by many 1990s Scottish filmmakers. This thesis presents the trajectory of the American agenda which dominated 1990s Scottish cinema within a 'Rise and Fall' paradigm. It proposes that the first half of the decade witnessed predominantly progressive local engagements, both industrially and ideologically speaking, with American film industrial and cultural practices. The latter part of the 1990s, however, was characterised by regressive misinterpretations of earlier, beneficial transatlantic appropriations. By the end of the decade, two things were clear about Scottish cinema's 1990s American agenda. Firstly, that agenda had either created or consolidated many previously lacking material conditions necessary for a sustainable national cinema. Secondly, that agenda had largely exhausted itself as a convincing blueprint for the further development of Scottish cinema.

In a period of proposed crisis and disruptive transformation to media, journalism and criticism, this thesis provides a comprehensive analysis of English-language film criticism by offering an empirically-grounded study of observations and interviews with some of the world’s foremost film critics and editors from influential publications such as Cineaste, CinemaScope, IndieWIRE, The Guardian, Reverse Shot, Sight & Sound and Variety. These expert opinions are not only situated in the wider context of historical perspectives on criticism from ancient and modern origins, but also positioned against on-going debates into journalism and digital media which often denote a landscape characterised by both continuity and contestation. The findings are drawn from extensive fieldwork in the UK and North America taking place at two major international film festivals in Edinburgh and Toronto, supplemented with additional interviews with film critics from each of these regions. This thesis relies upon a great deal of published literature, from text books and media coverage to film criticism. These materials detail a crisis in criticism and in the culture at large, a prehistory of existing media, concepts around literary and arts criticism in general, and provide the means for a detailed model on Six Schools of Contemporary Film Criticism to be posited. A combination of desk research with participant observation and in-depth interviews has led to and strengthened the overall findings which conclude that film criticism in the contemporary digital age is defined by more continuity than disruptive transformation. While this prosaic – but not myopic – approach to film criticism highlights the habits and norms of film critics it also notes the significant changes taking place through the interactions of individuals and institutions with technologies. However, while transformations are acknowledged and new events specified – indeed the theme of change gives shape to the findings chapters in terms of a chronology of the new, newer and newest – in print, then online and subsequently towards convergent media forms – it is argued that the long view best serves to counteract hyperbolic discourses on film criticism as dead or inhabiting a new golden age. These empirical findings, in the face of transformative digital idealism, redress the balance and argue the case for evolution rather than the often mooted digital revolution.

This thesis outlines and discusses portrayals of Albanian and Ethnic Greek migrants from Albania in contemporary Greek cinema. The focus is on seven coproduced films made between 1993 and 2009 that set out to challenge endemic xenophobia and nationalism. The latter have served the most in the exclusion of Albanian immigrants in Greece. The exclusion of Albanian migrants in Greece can be linked to a history of opposition between both countries which has led to a collective predisposition towards Albanians as inherently criminal. This is not an isolated event, but a broad phenomenon that saw Southern European cinemas becoming increasingly preoccupied with the presence of migrants in a region that has not been conditioned to hosting but rather to sending émigrés. Such films therefore also challenge the cultural bedrock of Greece and Europe. It is argued in this thesis that the shift from a national cinema to a transnational mode of filmmaking and representation, that asserts difference and a decline in national sovereignty, is an entirely alien experience to the history of Greek cinema. By utilising a holistic and critically informed framework and methodology, the author unpacks the films' creative and cultural context and addresses them as one body in relation to the specific cultural and historical backdrop. Consequently the texts per se are addressed in order to measure the degree to which they achieve a radical representation of difference and an overall shift from the norm of an insular cinema and film discourse. It is argued that the proposed films plant the seeds for an inclusive discourse but not without reinforcing obvious essentialisms that underlie nationalism and Eurocentrism. Therefore, the author argues that nationalism and Eurocentrism inform the films and hinder their aspiration towards a radical discourse.

This thesis explores the ways in which those who have experienced psychosis engage with and respond to film texts which feature psychosis; it draws upon screen theory and cultural theory to combine analysis of film content with reception analysis. Adopting a Foucauldian critical discourse analysis approach, (Jäger and Maier 2009) I employ textual analysis to examine the construction of psychosis in three key areas. Firstly, the naming of clinical psychosis is explored through an examination of policy documents. Secondly, a broad range of texts from the inception of film to the present day are analysed to investigate film images and narratives of both named and inferred ‘psychosis’. Ethical guidelines were observed in recruiting and carrying out twentyfour semi-structured interviews with respondents who have experienced psychosis (Koivisto et al 2001, Davies 2005, Horsfall et al 2007, Keogh & Daly 2009). The transcripts of these interviews provide the basis for my third area of discourse analysis; they are explored to determine respondents’ attitudes towards psychosis and films that feature it. In this study I argue that different hierarchies of discourse and procedures of power operate in the three distinct areas through mechanisms of nomination and exclusion (Fairclough 2009). Audience analysis reveals that respondents use film texts in order to make sense of and associatively re-create their experiences of psychosis. Making an original contribution to the field, I have identified the ways in which respondents appropriate specific texts as ‘evocative’ readings. Here, films which do not denotatively feature images/narratives of psychosis are read as highly relevant to respondents’ experiences of psychosis. My thesis makes a valuable contribution to audience studies by bringing together three areas of study in a way that has not been done before. It explores the interaction between audience and text and gives voice to a respondent cohort which has historically been marginalised. The concept of ‘evocative’ reading also enables me to challenge prior emphases on the ‘accurate’ representation of psychosis in popular film (Ritterfeld & Jin 2006, Pirkis et al 2006).