On the generation of environmentally efficient flight trajectories

To achieve a sustainable future for air transport, the International Civil Aviation Organization has proposed goals for reductions in community noise impact, local air quality and climate impacting emissions. The goals are intended to be achieved through advances in engine design, aircraft design and through improvements in aircraft operational procedures. This thesis focuses on operational procedures, and considers how trajectory generation methods can be used to support flight and airspace planners in the planning and delivery of environmentally efficient flight operations. The problem of planning environmentally efficient trajectories is treated as an optimal control problem that is solved through the application of a direct method of trajectory optimisation combined with a stochastic Non Linear Programming (NLP) solver. Solving the problem in this manner allows decision makers to explore the relationships between how aircraft are operated and the consequent environmental impacts of the flights. In particular, this thesis describes a multi-objective optimisation methodology intended to support the planning of environmentally efficient climb and descent procedures. The method combines environmental, trajectory and NLP methods to generate Pareto fronts between several competing objectives. It is shown how Pareto front information can then be used to allow decision makers to make informed decisions about potential tradeoffs between different environmental goals. The method is demonstrated through its application to a number of real world, many objective procedure optimisation studies. The method is shown to support in depth analysis of the case study problems and was used to identify best balance procedure characteristics and procedures in an objective, data driven approach not achievable through existing methods. Driven by operator specific goals to reduce CO2 emissions, work in this thesis also looks at trajectory based flight planning of CO2 efficient trajectories. The results are used to better understand the impacts of ATM constraints and recommended procedures on both the energy management and fuel efficiency of flights. Further to this, it is shown how trajectory optimisation methods can be applied to the analysis of conventional assumptions on fuel efficient aircraft operations. While the work within is intended to be directly relevant to the current air traffic management system, both consideration and discussion is given over to the evolution and continued relevance of the work to the Single European Sky trajectory based concept of operation

Hearing voices, dissociation and the self: a functional-analytic perspective

Item does not contain fulltextIn the current paper, we review existing models of the aetiology of voice hearing. We summarise the argument and evidence that voice hearing is primarily a dissociative process, involving critical aspects of self. We propose a complementary perspective on these phenomena that is based on a modern behavioural account of complex behaviour, known as Relational Frame Theory (RFT). This type of approach to voice hearing concerns itself with: the functions served for the individual by this voice hearing; the necessary history, such as trauma, that establishes these functions; and the relevant dissociative processes involving self and others. In short, we propose a trauma-dissociation developmental trajectory in which trauma impacts negatively on the development of self, through the process of dissociation. Using the RFT concept of relations of perspective-taking, our dissociation model purports that trauma gives rise to more co-ordination than distinction relations between self and others, thus weaking an individual's sense of a distinct self. Voice hearing experiences, therefore, reflect an individual's perceptions of self and others, and may indicate impairments in the natural psychological boundaries between these critical related concepts. One clinical implication suggested by this model is that therapeutic 'intervention' should understand the behaviours associated with a sense of self that is fragile and threatened by others. Relations with self and others should be a key focus of therapy, as well as interventions designed to enhance a coherent distinct sense of self.20 p

A pilot study of the relations within which hearing voices participates : towards a functional distinction between voice hearers and controls

The current research used the Implicit Relational Assessment Procedure (IRAP) as a preliminary step toward bringing a broad, functional approach to understanding psychosis, by focusing on the specific phenomenon of auditory hallucinations of voices and sounds (often referred to as hearing voices). On this path, we created a taxonomy of some critical features of voice hearing based on the existing literature (i.e., perceived normality of voices, appraisals of self and other people hearing voices, and fear of voices) as a focus of our experimental manipulations. It was our hope that our findings would add to the broad literature that has used explicit measures to study these phenomena, and that the use of an 'implicit' measure might assist toward a functional analytic understanding. Three pilot studies were conducted to assess the relations within which hearing voices participates in non-clinical voice hearers (i.e., individuals who hear voices but have no clinical diagnosis or distress) and compared to non-voice hearing control participants. The IRAP effects demonstrated both positive and negative relational responses across the three studies, and these effects varied according to explicit levels of delusional ideation. Furthermore, these IRAP effects also predicted explicit aspects of voice hearing and well-being. The current set of pilot studies demonstrate the utility and precision of the IRAP in this domain, and we propose that this type of experimental analysis may hold potential for future bottom-up functional analyses of voice hearing

Exploring the potential impact of relational coherence on persistent rule-following : the first study

Rule-governed behavior and derived relational responding have both been identified as important variables in human learning. Recent developments in the relational frame theory (RFT) have outlined a number of key variables of potential importance when analyzing the dynamics involved in derived relational responding. Recent research has explored the impact of one of these variables, level of derivation, on persistent rule-following and implicated another, coherence, as possibly important. However, no research to date has examined the impact of coherence on persistent rule-following directly. Across two experiments, coherence was manipulated through the systematic use of performance feedback, and its impact was examined on persistent rule-following. A training procedure based on the implicit relational assessment procedure (IRAP) was used to establish novel combinatorially entailed relations that manipulated the feedback provided on the trained relations (A-B and B-C) in Experiment 1, and on the untrained, derived relations (A-C) in Experiment 2. One of these relations was then inserted into the rule for responding on a subsequent contingency-switching match-to-sample (MTS) task to assess rule persistence. While no significant differences were found in Experiment 1, the provision or non-provision of feedback had a significant differential impact on rule-persistence in Experiment 2. Specifically, participants in the Feedback group resurged back to the original rule for significantly more responses after demonstrating contingency-sensitive responding than did the No-Feedback group, after the contingency reversal. The results highlight the subtle complexities that appear to be involved in persistent rule-following in the face of reversed reinforcement contingencies

UNIQUENESS of the WELDING PROBLEM for SLE and LIOUVILLE QUANTUM GRAVITY

AbstractWe give a simple set of geometric conditions on curves \unicode[STIX]{x1D702}, \widetilde{\unicode[STIX]{x1D702}} in $\mathbf{H}$ from $0$ to $\infty$ so that if \unicode[STIX]{x1D711}:\mathbf{H}\rightarrow \mathbf{H} is a homeomorphism which is conformal off \unicode[STIX]{x1D702} with \unicode[STIX]{x1D711}(\unicode[STIX]{x1D702})=\widetilde{\unicode[STIX]{x1D702}} then \unicode[STIX]{x1D711} is a conformal automorphism of $\mathbf{H}$. Our motivation comes from the fact that it is possible to apply our result to random conformal welding problems related to the Schramm–Loewner evolution (SLE) and Liouville quantum gravity (LQG). In particular, we show that if \unicode[STIX]{x1D702} is a non-space-filling \text{SLE}_{\unicode[STIX]{x1D705}} curve in $\mathbf{H}$ from $0$ to $\infty$, and \unicode[STIX]{x1D711} is a homeomorphism which is conformal on \mathbf{H}\setminus \unicode[STIX]{x1D702}, and \unicode[STIX]{x1D711}(\unicode[STIX]{x1D702}), \unicode[STIX]{x1D702} are equal in distribution, then \unicode[STIX]{x1D711} is a conformal automorphism of $\mathbf{H}$. Applying this result for \unicode[STIX]{x1D705}=4 establishes that the welding operation for critical (\unicode[STIX]{x1D6FE}=2) LQG is well defined. Applying it for \unicode[STIX]{x1D705}\in (4,8) gives a new proof that the welding of two independent \unicode[STIX]{x1D705}/4-stable looptrees of quantum disks to produce an \text{SLE}_{\unicode[STIX]{x1D705}} on top of an independent 4/\sqrt{\unicode[STIX]{x1D705}}-LQG surface is well defined.ERC Starting Grant 804166 (SPRS

Using the IRAP to explore natural language statements

This study explored a modification to the typical presentation of label and target stimuli on Implicit Relational Assessment Procedure (IRAP) effects. We asked whether combining the labels and targets into a single phrase would influence performances. The key purpose of the study was to determine the feasibility of altering the way in which stimuli are presented within the IRAP, so as to potentially employ more complex natural language-like statements in future research. In the Typical IRAP employed here, labels and targets were presented as separate words, while in the Natural Language IRAP they were combined to form a single statement. The results demonstrated no substantive differences in the effects recorded on both types of IRAP, thus supporting the future use of a Natural Language version