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The minimum clearing time problem in wireless networks
No full textEmpirical thesis.Bibliography: pages 53-54.1. Introduction -- 2. Tree networks -- 3. Ring networks -- 4. Future work -- References.The thesis focuses on the minimum time clearing objective for link scheduling in wireless networks. We formulate the problem as a deterministic LP. We relate the problem to other works on capacity and scheduling. In general, the problem is NP-complete. We consider special networks where the additional structure makes the problem tractable. We argue that explicitly solving the linear program is implausible. And proceed to show that the problemis amenable to a greedy allocation scheme that only requires local information.Beyond the special case, we consider simple ring networks where in general, the greedy solution is sub-optimal. We solve the minimum clearing time problem for ring networks under 1-hop interference model. We establish the sufficiency conditions for optimality of a greedy solution. We also provide the solution when these conditions do not hold. For this case, the solution depends on global information, unlike the greedy solution. However, the solution only has a linear complexity in terms of computation.The minimum clearing time problem can help us understand how the network is constrained under different load distributions. Ultimately, in the future we aim to use these insights to design a simple scheduling policy, with nearly optimal performance in a general wireless network.Mode of access: World wide web1 online resource (viii, 54 pages) diagram
Genre meshing in Chaucer and Shakespeare’s account of the legend of Troilus and Cressida
No full textTheoretical thesis.Bibliography: pages 79-99.Introduction -- Chapter One. Cultural and critical contexts -- Chapter Two. Chaucer’s Troilus and Criseyde : In giving agency to Criseyde, was Chaucer also overturning traditional gender conventions? -- Chapter Three. Shakespeare’s Troilus and Cressida : What role does mode play in the transmission of legendary materials? -- Conclusion -- Bibliography.This discussion aims to explore the links between the motivated manipulation of generic frameworks in legendary materials and how they can be utilised by authors to impart meaning. Chaucer and Shakespeare fashioned their own versions of the Trojan legend. This legend was critical to English history. Chaucer produced his popular poem Troilus and Criseyde, and centuries later Shakespeare wrote his play Troilus and Cressida. Though Chaucer and Shakespeare cover similar aspects of the legend, individually they both produced texts that were of problematical generic determination to their audiences and critics alike. Generic frameworks that are within individual texts can predispose the reader to knowledge connected with certain genre types. For instance, the medieval romance genre and tragedy genre both have certain familiar tropes and create expectations when poems or plays are classified as them. The adherence to, or defiance of, literary orthodoxies such as genre can also be an indication of how the authors thought of their own political and social circumstances. In order to further the discussion of the employment of genre or genres in the texts modern genre theory will be applied, as this theory allows for the inclusion of more than a singular genre in a single text.Mode of access: World wide web1 online resource (ii, 99 pages
Quantum interference through plasmonic nanostructures
No full textEmpirical thesis.Bibliography: pages 79-90.1. General introduction -- 2. Technical introduction -- 3. Controlling the SPDC wave function -- 4. Measuring the SPDC wave function -- 5. Two-photon interactions with nanoapertures -- 6. Conclusion -- Appendices -- References.Quantum technologies like quantum computing, quantum communication or quantum metrology promise astonishing advantages over their classical counterparts. However, they all require excellent control and protection of the involved quantum states. In this respect, photons are ideal carriers of quantum information due to their robustness against decoherence and the ease with which they can be transferred over long distances. At the same time they suffer from weak interactions with matter and the large structures necessary, as given by the wavelength of light. Combining quantum optics with plasmonic structures could open an avenue to address these drawbacks while still benefiting from the advantages of photons.We present for the first time the transmission of an entangled two-photon state through a plasmonic aperture that is smaller than the wavelength of the light. Entanglement is the key resource for many quantum information schemes and its protection of great interest. Strong interactions with the nanoaperture usually destroy the entanglement of an arbitrary state. We tailor a special state for the interaction – taking into account the specific properties of the aperture – that leads to quantum interference and eventually protects the entanglement from degradation. We experimentally demonstrate creation of this state, transmission through the nanoaperture and successful protection of the entanglement.On our way to this achievement, we improve our control over the spontaneous parametric down-conversion source of photon pairs. We report a surprising dependence of the time delay distribution between the photons of the pair on the position of the non-linear crystal. We experimentally confirm the effect via quantum interference experiments and challenging direct measurements of the arrival time. Furthermore, a novel reconstruction scheme for the complex spectral biphoton wave function allows us to study the temporal correlations in more detail and to shape the wave function. We experimentally demonstrate the reconstruction in different situations and find an unexpected temporal distribution with a detection mode carrying orbital angular momentum.Mode of access: World wide web1 online resource (xiv, 91 pages) illustrations (some colour
Functional properties, neurochemistry and connectivity of medullary neural networks that control breathing and circulation
No full textEmpirical thesis.Bibliography: pages 144-188.1. Introduction -- 2. Recording, labelling and transfection of single neurons in deep brain structures -- 3. Somatostatin 2a receptors are not expressed on functionally identified respiratory neurons in the ventral respiratory column of the rat -- 4. The connectome of rostral ventrolateral medulla C1 neurons -- 5. General discussion -- References -- Appendices.The autonomic nervous system governs basic homeostatic functions such as regulating cardiac output, blood pressure, body temperature, and the generation of respiratory rhythm. Although traditionally conceptualised as independent entities, the neural networks that underlie respiratory rhythm and vasomotor tone are intimately connected, with each component influencing the activity of the other. This respiratory-sympathetic coupling contributes to cardiac sinus arrhythmia and underlies the strong respiratory modulation of vasomotor sympathetic nerve activity, which may play an important role in initiation and development of neurogenic hypertension. The experiments described in this thesis explore the neurochemical profiles, functional properties, and circuit architecture of medullary neurons that control breathing and circulation.Genetically modifying a single functionally identified neuron in an intact neural network would provide the ultimate way to bridge neuronal circuit structure and function. The work described in Chapter 2 of this thesis describes a novel method that combines extracellular recording with the labelling of neurons recorded in the ventral lateral medulla with either dyes or plasmid DNA, permitting conventional cell labelling or gene delivery. We demonstrate that our approach has several advantages over traditional single-cell labelling approaches, and therefore provides a useful tool for correlation of functional properties of single neurons with their neurochemical phenotypes that can also be used for targeted single cell gene delivery under blind recording conditions.We then apply this technique to address a controversial topic in the field of respiratory neuroscience; the neurochemical signature of the neurons responsible for generating respiratory rhythm. Previous investigations have suggested that the neuropeptide somatostatin plays a critical role in respiratory rhythmogenesis and is a marker for excitatory respiratory interneurons in the pre-Bötzinger complex (preBötC). Somatostatin receptor type 2a (sst₂ₐ) has been postulated as a mediator of such effects, and has also been proposed as a marker for respiratory neurons. In Chapter 3 we systematically examine the expression pattern of sst₂ₐ with regards to the functionally distinguished subcomponents of the ventral respiratory column. We further examine the feasibility of sst₂ₐ as a reliable marker of respiratory function at the single cell level.In Chapter 4 we examine the anatomical substrate responsible for linking the respiratory and sympathetic circuits using a modified trans-synaptic tracing tool. We first extensively map sources of monosynaptic drive to putative sympathetic premotor neurons in the rostral ventrolateral medulla (RVLM) using a genetically restricted rabies variant, that is selectively directed towards RVLM neurons that express the Phox2b transcription factor. We identify likely sources of inputs within brainstem compartments with proven roles in generation of respiratory rhythm and phase transition in normotensive animals.The data from this thesis extends our knowledge of respiratory neuroanatomy and provides important clues to the organisation of the circuits that underlie respiratory-sympathetic coupling.Mode of access: World wide web1 online resource (xiii, 189 pages) illustrations (some colour
The teaching of communication strategies to non-English major students in Vietnam
No full textTheoretical thesis.Includes bibliographic references.Chapter 1: Introduction -- Chapter 2: Communication strategies and contexts -- Chapter 3: Methodology -- Chapter 4: Findings and discussions -- Chapter 5: Conclusion.This thesis reports on an investigation into the teaching of communication strategies (CSs) to non-English major students in Vietnam, with special attention to teachers' perspectives, and university curricula and teaching materials used at this level. A mixed-method approach was used. A survey was used to collect data from Vietnamese teachers of English to non-English major students, on the extent to which they were aware of the nature of CSs, and their views on the integration of CSs into the teaching of English to their students. This was combined with an analysis of the English teaching curricula used in all the universities surveyed, and a close analysis of the teaching texts used in one of these universities, in order to further clarify teachers' views on CSs and to see whether the content of the curricula and teaching texts at this level encourages the teaching of CSs.The findings show that, although the vast majority of the respondents supported integrating CSs into their teaching of spoken English to non-major students, many of them had an incomplete grasp of what CSs actually are, and few had been trained in how to teach them. Importantly, the teaching curricula of the universities surveyed did not cover CSs, nor did the teachers use supplementary supplementary teaching materials to teach them. Analysis of the teaching texts used by the majority of the respondents also indicated that these texts do not explicitly introduce the topic of CSs per se, although they do illustrate some CSs in several dialogues. In this way, they do illustrate how they work to some extent and provide some relevant vocabulary and practice. They therefore provide a source from which the teachers can draw in order to teach CSs. However, the teachers were not fully aware of exactly how CSs are treated in the texts, and thus did not fully exploit their potential in their teaching of spoken English to their students. The respondents did, however, offer some suggestions for how CS instruction could be incorporated into the teaching of English. On the basis of these analyses, specific recommendations for the development of appropriate CS practice materials and activities to teach spoken English to Vietnamese non-majors of English are proposed.Mode of access: World wide web1 online resource (x, 62, [15], 8 pages
Source effect scale
No full textEmpirical thesis.Running title: The source effect scale.Bibliography: pages 45-50.Introduction -- Study 1. The development of a source effect scale -- Study 2. Behavioural exploration of the source effect -- Conclusion -- References -- Appendix.The source effect for disgust is the tendency for disgust elicitors emanating from unfamiliar others to elicit higher levels of disgust than those emanating from the self or close others (Case, Repacholi & Stevenson, 2006; Repacholi & Stevenson, 2005). Prior to this research, there was no distinct measure for the source effect. One of the reasons for this was the source effect has been compared to self-disgust which already has existing measurement tools. In Study 1 (N = 189), to demonstrate that the source effect is different to self-disgust, a valid and reliable measure of the source effect was developed and administered with measures of self-concept, self-disgust and disgust sensitivity. Findings indicate that self-disgust is more likened to an intense experience of shame as oppose to disgust. The source effect measure was revealed to be a reliable measure of the source effect, although it did not relate with disgust sensitivity, suggesting there are potentially other influential factors for the source effect. In Study 2 (N = 16), a behavioural measure of the source effect was implemented through a priming and stimulus engagement experiment. Participants were primed to a shame, anger or neutral condition and then were tested for the source effect towards disgust elicitors from the self and an unknown stranger. Preliminary findings suggest that shame may cause an individual to become more avoidant of their own disgust elicitors. Potential utility of the new measures and future research directions are discussed.Mode of access: World wide web1 online resource (82 pages
Neural responses to morphosyntactic violations in foreign accented speech
No full textTheoretical thesis.Bibliography: Pages 68-76.1. Introduction -- 2. Literature review -- 3. Methodology -- 4. Results -- 5. Discussion -- 6. Conclusion.When comprehending speech, listeners extract information regarding the speaker's characteristics, such as their sex, nationality or socioeconomic status, from the speech signal. This speaker-identity information is integrated on-line during speech processing, influencing how listeners process both the phonological and semantic content of the utterance. However, little is known as to whether morphosyntactic processing is also influenced by the integration of of the speaker's identity. This study used the event-related potential technique to examine whether listeners' (n-30) neural responses to morphosyntactic violations (here subject-verb agreement errors) were modulated by the presence of speaker-identity information in the form of a foreign accent. The results demonstrated that the presence of a foreign accent did affect the neural responses observed for the violations, with errors of the commission type (where a superfluous morpheme was present) eliciting an N400 effect in native speech but an anterior negativity in foreign accented speech. However, omission errors (where a required morpheme was missing) elicited no violation effect for either speaker. The unexpected presence of an N400 effect was attributed to shallow syntactic processing and a possible priming effect caused by the presence of semantic violations in the experimental stimuli. The lack of effect observed for omission errors was attributed to the relative lack of perceptual salience of this error type. Some individual variation in the neural responses was observed, which was weakly related to participants' empathy levels. Overall, the results provided evidence that speaker-identity information is indeed integrated on-line during morphosyntactic processing.Mode of access: World wide web1 online resource (92 pages
Playing the price game!: an exploratory study in retail in-aisle consumer decision making ... : or why consumers really walk-away
No full textTheoretical thesis.Bibliography: pages 45-49.1 Introduction -- 2 Literature Review -- 3 Research Methodology -- 4 Research findings -- 5 Discussion -- 6 Conclusion and future Research.In this era of self-service shopping, the retail industry is witnessing intense competition like never before. Retailers are continuously improving their in-store shopping experience to attract more customers to sustain in this competitive market. Even though online shopping market is rapidly growing, consumers still prefer to shop in-store as they can feel, touch and check the product. In the past, research has been done to understand the consumer choice and decision making, but this research seldom focuses on the aspect of in-aisle choice process of consumers and their non-purchase decision about products in retail stores. The present study explores this gap in the literature by using eye-tracking glasses to understand the in-aisle consumer decision making while purchasing products in a real store environment.This study is exploratory in nature and uses eye-tracking technology to understand how a consumer shows choice behaviour in the store. Eye-tracking glasses tracks the eye movement of shoppers as to which shelf and which product in an aisle they are having a look at and which part of the product package they are interested to look at. The aim of the study is to understand in-aisle consumer decision making, choice behaviour and walk-aways from shelves. This study is conducted in a pharmacy and green grocery store. The present study uses both qualitative and quantitative methods to form a theory. This study collects data using video, interview and questionnaire. This study uses a grounded theory approach.It has been found that consumers look at brand name, price and product description of the product in pharmacy store. A majority of the consumers don't look at the ingredients and directions while buying medicines, as they trust the pharmacist. In a green grocery store, shoppers look at the product and price with more focus on choosing the vegetables and fruits carefully. Consumers' walk-away from pharmacy and grocery shelves if they don't find the brand of product on the shelf or the price of the product is perceived to be expensive by the consumers. This project suggests consumer in-aisle choice processes involved in in-aisle choice behaviour generating in-aisle consumer decisions to purchase or not to purchase products in a pharmacy and green grocery store.This project contributes theoretically by providing the reasons behind walk-aways, which has largely been introspective, and non-academic in nature, and suggesting a consumer choice process integral to in-aisle choice behaviour generating decision-making of purchasing products encompassing real time shopping in a real environment. This project also contributes methodologically by using both quantitative and qualitative methods to understand in-depth about consumer decision making which has only been in quantitative form in the present literature. Thus , consumer's in-aisle choice process differs from stre to store and more research needs to be done with a large sample of population and in different types of retail stores to get a better understanding of complex consumer in-aisle choice behaviour and decision-making.Mode of access: World wide web1 online resource (x, 100 leaves) illustrations (some colour
Hannibal: imagining the enemy in the Roman Republic
No full textTheoretical thesis.Bibliography: pages 77-89.Introduction -- Chapter One. On ‘gender’ -- Chapter Two. Roman ‘gender’ -- Chapter Three. Republican Hannibals -- Chapter Four: Livy’s Hannibal --Conclusion-- Bibliography.What we understand as 'gender' and 'sexuality' were interrelated concepts, nested within the patchwork of moral and immoral behaviours defined within the value system of the Roman elite. Roman authors perpetuated this discourse in a moralising fashion, using illustrious and notorious Romans as behavioural exemplars; but what of foreign enemies? How did Roman 'gender' values affect their representation by Latin writers such as Cicero and Livy? Hannibal is known to us predominantly through reports of his clashes with Rome. This thesis examines the representations of Hannibal by Cicero, Livy, and some of their sources, arguing for, inter alia, a 'gendered' representation.Mode of access: World wide web1 online resource (viii, 89 pages
Epistemic justice: confronting implicit bias, explicit prejudice, and epistemiology of oppression
No full textTheoretical thesis.Bibliography: Pages 69-72.1. Introduction -- 2. Fricker's notion of testimonial (in)justice -- 3. Virtues rather than virtue of testimonial justice -- 4. Fricker's non-individualistic concerns -- 5. Explicit prejudice and the Grand Cyclops example -- 6. From implicit bias to explicitly held prejudice to epistemology of oppression -- 7. John Doris' collaborative account of agency -- 8. The virtue of condemning and reacting to vices -- 9. Group virtues and system level virtues -- 10. Conclusion.This thesis attempts to further develop Fricker's notion of epistemic justice. Fricker defines epistemic justice, in the Aristotelian tradition, as a virtue of character. However, given that epistemic justice is also a corrective measure to the various forms of epistemic injustice, it seems as an inadequate corrective response in its current individualistic and virtue-theoretic form. Keeping the virtue-theoretic form of epistemic justice - though briefly alluding to its inadequacies as well, I explore various social roles that can cultivate this virtue as a corrective to epistemic injustice. I do so by horizontally and vertically expanding the social landscape where epistemic injustice occurs. Horizontal expansion reveals that every instance of epistemic injustice includes three distinct social roles that consists of the perpetrator, the victim and possibly the audience or witnesses of the injustice. Certain epistemic justice virtues can be construed for each of these roles. Vertical expansion reveals three distinct layers in the social system where epistemic injustice can be located, namely the layer where individual agents perform, the layer where collectives are formed and operate, and the broader social system. A socially situated view op epistemic injustice allows imagining non-individualistic virtues, such as the virtues of groups and the virtues that exist in the social systems.Mode of access: World wide web1 online resource (72 pages