820 resultados para Phd


Relevância:

10.00% 10.00%

Publicador:

Resumo:

This thesis draws on the work of Franz Neumann, a critical theorist associated with the early Frankfurt School, to evaluate liberal arguments about political legitimacy and to develop an original account of the justification for the liberal state.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The foraging strategies of two natural enemies of the peach-potato aphid Myzus persicae: the seven-spot ladybird Coccinella septempunctata and the parasitoid wasp Diaeretiella rapae, were investigated. Specifically the roles of plant semiochemicals in the location of plants infested with M. persicae by these natural enemies were examined. I investigated the olfactory responses of female C. septempunctata to volatiles collected from M. persicae and four Brassica cultivars; Brassica rapa, B. juncea, B. napus cultivar ‘Apex’ and B. napus cultivar ‘Courage’ and wild-type Arabidopsis thaliana that were: undamaged, previously infested by M. persicae and infested with M. persicae. C. septempunctata showed no attraction to volatiles from M. persicae alone. C. septempunctata significantly changed its searching behaviour in response to plant volatiles from B. rapa, B. napus cv. ‘Apex’ and Arabidopsis infested with M. persicae. C. septempunctata was also found to display a significant turning bias when foraging on a branching horizontal wire stem. A model was developed to investigate how turning biases affect the foraging efficiency of C. septempunctata in dichotomous branched environments. Simulations using this model indicated that turning biases could potentially increase searching efficiency. D. rapae showed a significant preference for volatiles from M. persicae infested wild-type Arabidopsis but no preference to volatiles from M. persicae alone or M. persicae honeydew. Volatile emissions by Arabidopsis were shown to be localised to the area of aphid-infestation rather than systemic. Using gas chromatography plants infested with M. persicae were shown to emit a quantitatively different volatile blend than undamaged plants. In experiments with jasmonate mutants of Arabidopsis the jasmonate (octadecanoid) wound response pathway was implicated as being important for the production of M. persicae induced volatiles, attractive to D. rapae. Other wound response pathways were also found to be involved in the production of the full blend of M. persicae induced volatiles.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This research explores whether patterns of typographic differentiation influence readers’ impressions of documents. It develops a systematic approach to typographic investigation that considers relationships between different kinds of typographic attributes, rather than testing the influence of isolated variables. An exploratory study using multiple sort tasks and semantic differential scales identifies that readers form a variety of impressions in relation to how typographic elements are differentiated in document design. Building on the findings of the exploratory study and analysis of a sample of magazines, the research describes three patterns of typographic differentiation: high, moderate, and low. Each pattern comprises clusters of typographic attributes and organisational principles that are articulated in relation to a specified level of typographic differentiation (amplified, medium, or subtle). The patterns are applied to two sets of controlled test material. Using this purposely-designed material, the influence of patterns of typographic differentiation on readers’ impressions of documents is explored in a repertory grid analysis and a paired comparison procedure. The results of these studies indicate that patterns of typographic differentiation consistently shape readers’ impressions of documents, influencing judgments of credibility, document address, and intended readership; and suggesting particular kinds of engagement and genre associations. For example, high differentiation documents are likely to be considered casual, sensationalist, and young; moderate differentiation documents are most likely to be seen as formal and serious; and low differentiation examples are considered calm. Typographic meaning is shown to be created through complex, yet systematic, interrelationships rather than reduced to a linear model of increasing or decreasing variation. The research provides a way of describing typographic articulation that has application across a variety of disciplines and design practice. In particular, it illuminates the ways in which typographic presentation is meaningful to readers, providing knowledge that document producers can use to communicate more effectively.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Because reading groups historically have been under-researched (Long, 2003), the literature in this field is limited, presenting this as an interesting area for researchers. A need for further research is also explained by the fact that the traditional model of a reading group has been expanded through recent library policies leading to the development of specific group types such as groups for visually-impaired people (VIPs). To date, there have been no long-term empirical studies of these groups. This thesis, therefore, makes a significant contribution to the literature in this field by providing an in-depth exploration of a VIP reading group. The thesis is an ethnographic study which follows a library-run reading group for visually-impaired people from its formation in September 2007 and concentrates on five of the group members. The methodology for the study is influenced by participatory approaches to research involving disabled people by inviting the participants to participate in the co-creation of knowledge about themselves (French & Swain, 2000, p. 1). It is also influenced by new ethnography’s preference for multi-layered texts by exploring both the individual and collective experiences of the participants. While the participants are defined throughout as readers, visual-impairment plays a role in their experiences. I show that visually-impaired readers and reading groups sit within a complex web of factors which impact on their experiences both as individual readers and as a group. The study also shows that VIP reading groups challenge traditional definitions of reading as a visual activity. The study explores issues of power and concludes that, because ownership of the group lies with the library, this challenges the idea of reading groups empowering their members. Furthermore, offering discrete groups for visually-impaired readers means that the role these groups play in contributing to agendas for social inclusion is problematic. The study concludes by making suggestions as to how these groups might develop to be more inclusive and empowering.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This thesis examines the film comedies directed by Olga Malea and released between 1997 and 2007 in Greece, in order to make a claim for the study of women’s popular cinema in Greece and beyond. Women’s popular cinema refers to films which are thematically associated with women’s cinema while operating in popular forms, such as genre. Olga Malea and her work make for a useful case study, in that they encapsulate the relationship between these two broad categories of women’s cinema and popular cinema. In addition, this thesis claims that the two categories inflect one another in interesting ways, and their intersections act as a productive framework for the analysis of women’s cinema as popular cinema, effecting a popularisation of usually marginalised themes. The introduction to this work primarily outlines the theoretical frameworks for the argument that follows, namely: women’s cinema and feminist theory; discussions around popular cinema; and considerations about authorship. The concept of national film cultures and its possible meaning in relation to Greece is also alluded to as a contextual factor. Each subsequent chapter advances the argument for women’s popular cinema through close textual analysis of the films in chronological order of their release. In particular, the analysis identifies recurrent strands and motifs in the director’s oeuvre, such as tensions between tradition and modernity, and the pervasive nature of patriarchy in informing national gender discourses. Having established the argument that women’s popular cinema is productive in popularising women’s cinema itself, the thesis concludes that, in the work of Olga Malea, its themes are conceived of, represented and perceived as prominent in the country during the period examined – and one can finally address women’s cinema as popular.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Landscape scale habitat restoration has the potential to reconnect habitats in fragmented landscapes. This study investigates landscape connectivity as a key to effective habitat restoration in lowland agricultural landscapes and applies these findings to transferable management recommendations. The study area is the Stonehenge World Heritage Site, UK, where landscape scale chalk grassland restoration has been implemented. Here, the ecological benefits of landscape restoration and the species, habitat and landscape characteristics that facilitate or impede the enhancement of biodiversity and landscape connectivity were investigated. Lepidoptera were used as indictors of restoration success and results showed restoration grasslands approaching the ecological conditions of the target chalk grassland habitat and increasing in biodiversity values within a decade. Restoration success is apparent for four species with a broad range of grass larval host plants (e.g. Melanargia galathea, Maniola jurtina) or with intermediate mobility (Polyommatus icarus). However, two species with specialist larval host plants and low mobility (Lysandra bellargus), are restricted to chalk grassland fragments. Studies of restoration grassland of different ages show that recent grassland restoration (1 or 2 years old) may reduce the functional isolation of chalk grassland fragments. A management experiment showed that mowing increases boundary following behaviour in two species of grassland Lepidoptera; Maniola jurtina and Zygaena filipendulae. Analysis of the landscape scale implications of the grassland restoration illustrates an increase in grassland habitat network size and in landscape connectivity, which is likely to benefit the majority of grassland associated Lepidoptera. Landscape and habitat variables can be managed to increase the success of restoration projects including the spatial targeting of receptor sites, vegetation structure and selection of seed source and management recommendations are provided that are transferrable to other species-rich grassland landscape scale restoration projects. Overall results show restoration success for some habitats and species within a decade. However, additional management is required to assist the re-colonisation of specialist species. Despite this, habitat restoration at the landscape scale can be an effective, long term approach to enhance butterfly biodiversity and landscape connectivity.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Subdermal magnetic implants originated as an art form in the world of body modification. To date an in depth scientific analysis of the benefits of this implant has yet to be established. This research explores the concept of sensory extension of the tactile sense utilising this form of implantation. This relatively simple procedure enables the tactile sense to respond to static and alternating magnetic fields. This is not to say that the underlying biology of the system has changed; i.e. the concept does not increase our tactile frequency response range or sensitivity to pressure, but now does invoke a perceptual response to a stimulus that is not innately available to humans. Within this research two social surveys have been conducted in order to ascertain one, the social acceptance of the general notion of human enhancement, and two the perceptual experiences of individuals with the magnetic implants themselves. In terms of acceptance to the notion of sensory improvement (via implantation) ~39% of the general population questioned responded positively with a further ~25% of the respondents answering with the indecisive response. Thus with careful dissemination a large proportion of individuals may adopt this technology much like this if it were to become available for consumers. Interestingly of the responses collected from the magnetic implants survey ~60% of the respondents actually underwent the implant for magnetic vision purposes. The main contribution of this research however comes from a series of psychophysical testing. In which 7 subjects with subdermal magnetic implants, were cross compared with 7 subjects that had similar magnets superficially attached to their dermis. The experimentation examined multiple psychometric thresholds of the candidates including intensity, frequency and temporal. Whilst relatively simple, the experimental setup for the perceptual experimentation conducted was novel in that custom hardware and protocols were created in order to determine the subjective thresholds of the individuals. Abstract iv The overall purpose of this research is to utilise this concept in high stress scenarios, such as driving or piloting; whereby alerts and warnings could be relayed to an operator without intruding upon their other (typically overloaded) exterior senses (i.e. the auditory and visual senses). Hence each of the thresholding experiments were designed with the intention of utilising the results in the design of signals for information transfer. The findings from the study show that the implanted group of subjects significantly outperformed the superficial group in the absolute intensity threshold experiment, i.e. the implanted group required significantly less force than the superficial group in order to perceive the stimulus. The results for the frequency difference threshold showed no significant difference in the two groups tested. Interestingly however at low frequencies, i.e. 20 and 50 Hz, the ability of the subjects tested to discriminate frequencies significantly increased with more complex waveforms i.e. square and sawtooth, when compared against the typically used sinewave. Furthermore a novel protocol for establishing the temporal gap detection threshold during a temporal numerosity study has been established in this thesis. This experiment measured the subjects’ capability to correctly determine the number of concatenated signals presented to them whilst the time between the signals, referred to as pulses, tended to zero. A significant finding was that when altering the length of, the frequency of, and the number of cycles of the pulses, the time between pulses for correct recognition altered. This finding will ultimately aid in the design of the tactile alerts for this method of information transfer. Preliminary development work for the use of this method of input to the body, in an automotive scenario, is also presented within this thesis in the form of a driving simulation. The overall goal of which is to present warning alerts to a driver, such as rear-to-end collision, or excessive speeds on roads, in order to prevent incidents and penalties from occurring. Discussion on the broader utility of this implant has been presented, reflecting on its potential use as a basis for vibrotactile, and sensory substitution, devices. This discussion furthers with postulations on its use as a human machine interface, as well as how a similar implant could be used within the ear as a hearing aid device.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The aim of this study was to first evaluate the benefits of including Jersey milk into Holstein-Friesian milk on the Cheddar cheese making process and secondly, using the data gathered, identify the effects and relative importance of a wide range of milk components on milk coagulation properties and the cheese making process. Blending Jersey and Holstein-Friesian milk led to quadratic trends on the size of casein micelle and fat globule and on coagulation properties. However this was not found to affect the cheese making process. Including Jersey milk was found, on a pilot scale, to increase cheese yield (up to + 35 %) but it did not affect cheese quality, which was defined as compliance with the legal requirements of cheese composition, cheese texture, colour and grading scores. Profitability increased linearly with the inclusion of Jersey milk (up to 11.18 p£ L-1 of milk). The commercial trials supported the pilot plant findings, demonstrating that including Jersey milk increased cheese yield without having a negative impact on cheese quality, despite the inherent challenges of scaling up such a process commercially. The successful use of a large array of milk components to model the cheese making process challenged the commonly accepted view that fat, protein and casein content and protein to fat ratio are the main contributors to the cheese making process as other components such as the size of casein micelle and fat globule were found to also play a key role with small casein micelle and large fat globule reducing coagulation time, improving curd firmness, fat recovery and influencing cheese moisture and fat content. The findings of this thesis indicated that milk suitability for Cheddar making could be improved by the inclusion of Jersey milk and that more compositional factors need to be taken into account when judging milk suitability.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Dominant paradigms of causal explanation for why and how Western liberal-democracies go to war in the post-Cold War era remain versions of the 'liberal peace' or 'democratic peace' thesis. Yet such explanations have been shown to rest upon deeply problematic epistemological and methodological assumptions. Of equal importance, however, is the failure of these dominant paradigms to account for the 'neoliberal revolution' that has gripped Western liberal-democracies since the 1970s. The transition from liberalism to neoliberalism remains neglected in analyses of the contemporary Western security constellation. Arguing that neoliberalism can be understood simultaneously through the Marxian concept of ideology and the Foucauldian concept of governmentality – that is, as a complementary set of 'ways of seeing' and 'ways of being' – the thesis goes on to analyse British security in policy and practice, considering it as an instantiation of a wider neoliberal way of war. In so doing, the thesis draws upon, but also challenges and develops, established critical discourse analytic methods, incorporating within its purview not only the textual data that is usually considered by discourse analysts, but also material practices of security. This analysis finds that contemporary British security policy is predicated on a neoliberal social ontology, morphology and morality – an ideology or 'way of seeing' – focused on the notion of a globalised 'network-market', and is aimed at rendering circulations through this network-market amenable to neoliberal techniques of government. It is further argued that security practices shaped by this ideology imperfectly and unevenly achieve the realisation of neoliberal 'ways of being' – especially modes of governing self and other or the 'conduct of conduct' – and the re-articulation of subjectivities in line with neoliberal principles of individualism, risk, responsibility and flexibility. The policy and practice of contemporary British 'security' is thus recontextualised as a component of a broader 'neoliberal way of war'.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Industrial robotic manipulators can be found in most factories today. Their tasks are accomplished through actively moving, placing and assembling parts. This movement is facilitated by actuators that apply a torque in response to a command signal. The presence of friction and possibly backlash have instigated the development of sophisticated compensation and control methods in order to achieve the desired performance may that be accurate motion tracking, fast movement or in fact contact with the environment. This thesis presents a dual drive actuator design that is capable of physically linearising friction and hence eliminating the need for complex compensation algorithms. A number of mathematical models are derived that allow for the simulation of the actuator dynamics. The actuator may be constructed using geared dc motors, in which case the benefits of torque magnification is retained whilst the increased non-linear friction effects are also linearised. An additional benefit of the actuator is the high quality, low latency output position signal provided by the differencing of the two drive positions. Due to this and the linearised nature of friction, the actuator is well suited for low velocity, stop-start applications, micro-manipulation and even in hard-contact tasks. There are, however, disadvantages to its design. When idle, the device uses power whilst many other, single drive actuators do not. Also the complexity of the models mean that parameterisation is difficult. Management of start-up conditions still pose a challenge.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Adsorption of small molecules on the Ni{111} and NiO{111} surfaces is investigated under UHV and elevated pressures (~10-1 mbar) of hydrogen and water. The molecules considered are chosen for their relevance to understanding the mechanism of enantioselective hydrogenation on Raney Nickel modified by chiral molecules. Adsorption of water onto, and its subsequent reaction with, oxygen-covered Ni{111} is dependent on the initial atomic oxygen coverage. An OH species (O1s binding energy 531.5eV), oriented perpendicular to the surface, forms at atomic oxygen coverages <0.25ML. The reaction does not consume all the adsorbed oxygen for coverages ≥0.12ML. The p(2×2) atomic oxygen uperstructure is unreactive, while an OH species is formed on the p(√3×√3) superstructure at binding energy 530.9eV. L-alanine is adsorbed on Ni{111} as a model chiral modifier molecule. At low coverages, alanine forms a presumed tridentate alaninate species for coverages ≥0.11ML at 250K. A minority, bidentate zwitterionic species forms at coverages >0.11ML, but was not observed at 300K. Saturation occurs at 0.25ML. At high alanine coverages (≥0.19ML) and H2 pressure (≥1×10-2 mbar), the tridentate L-alaninate converts to bidentate zwitterionic L-alanine at 300K. Thermal evolution of L-alanine on Ni{111} under varying hydrogen pressures is examined. Adsorption of L-alanine onto hydroxylated NiO{111} at 300K in UHV, mimicking a catalyst surface under aqueous conditions, yields the tridentate alaninate which is immune to the effects of elevated hydrogen pressure. Exposing the L-alanine/Ni{111} adsorption system to water (≤10-1 mbar) oxidises the surface and recreates the L-alanine/hydroxylated NiO{111} system. Pyruvic acid on Ni{111} is examined as a model for hydrogenation substrate adsorption. Behaviour is coverage dependent and several conformations are possible at low coverages (≤0.1ML). Annealing at coverages <0.2ML causes a condensation reaction, releasing water onto the surface. High coverages do not condense and a saturation coverage of ~0.35ML is found.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

During the last few years Enterprise Architecture has received increasing attention among industry and academia. Enterprise Architecture (EA) can be defined as (i) a formal description of the current and future state(s) of an organisation, and (ii) a managed change between these states to meet organisation’s stakeholders’ goals and to create value to the organisation. By adopting EA, organisations may gain a number of benefits such as better decision making, increased revenues and cost reductions, and alignment of business and IT. To increase the performance of public sector operations, and to improve public services and their availability, the Finnish Parliament has ratified the Act on Information Management Governance in Public Administration in 2011. The Act mandates public sector organisations to start adopting EA by 2014, including Higher Education Institutions (HEIs). Despite the benefits of EA and the Act, EA adoption level and maturity in Finnish HEIs are low. This is partly caused by the fact that EA adoption has been found to be difficult. Thus there is a need for a solution to help organisations to adopt EA successfully. This thesis follows Design Science (DS) approach to improve traditional EA adoption method in order to increase the likelihood of successful adoption. First a model is developed to explain the change resistance during EA adoption. To find out problems associated with EA adoption, an EA-pilot conducted in 2010 among 12 Finnish HEIs was analysed using the model. It was found that most of the problems were caused by misunderstood EA concepts, attitudes, and lack of skills. The traditional EA adoption method does not pay attention to these. To overcome the limitations of the traditional EA adoption method, an improved EA Adoption Method (EAAM) is introduced. By following EAAM, organisations may increase the likelihood of successful EA adoption. EAAM helps in acquiring the mandate for EA adoption from top-management, which has been found to be crucial to success. It also helps in supporting individual and organisational learning, which has also found to be essential in successful adoption.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

It has been suggested that Assessment for Learning (AfL) plays a significant role in enhancing teaching and learning in mainstream educational contexts. However, little empirical evidence can support these claims. As AfL has been shown to be enacted predominantly through interactions in primary classes, there is a need to understand if it is appropriate, whether it can be efficiently used in teaching English to Young Learners (TEYL) and how it can facilitate learning in such a context. This emerging research focus gains currency especially in the light of SLA research, which suggests the important role of interactions in foreign language learning. This mixed-method, descriptive and exploratory study aims to investigate how teachers of learners aged 7-11 understand AfL; how they implement it; and the impact that such implementation could have on interactions which occur during lessons. The data were collected through lesson observations, scrutiny of school documents, semi-structured interviews and a focus group interview with teachers. The findings indicate that fitness for purpose guides the implementation of AfL in TEYL classrooms. Significantly, the study has revealed differences in the implementation of AfL between classes of 7-9 and 10-11 year olds within each of the three purposes (setting objectives and expectations; monitoring performance; and checking achievement) identified through the data. Another important finding of this study is the empirical evidence suggesting that the use of AfL could facilitate creating conditions conducive to learning in TEYL classes during collaborative and expert/novice interactions. The findings suggest that teachers’ understanding of AfL is largely aligned with the theoretical frameworks (Black & Wiliam, 2009; Swaffield, 2011) already available. However, they also demonstrate that there are TEYL specific characteristics. This research has important pedagogical implications and indicates a number of areas for further research.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In recent decades, intuitions' role in philosophy has been hotly debated. Many claim intuitions play an important role. Others, some armed with data, challenge the use of intuitions. This thesis reflects on this debate and advances the debate in two main ways. Having a clear understanding of the challenge which intuition-use in philosophy faces is important. Part I focuses on this. Chapters 1-2 introduce the topic of intuitions, motivate the methodological study of intuitions, and present the historical background to recent empirical challenges to intuition-use. Chapters 3-5 concern the contemporary challenge. I present the empirical evidence the challenge uses, present what I argue to be the strongest version of the challenge, and defend that challenge against some objections. How one characterises intuitions is incredibly important in philosophical methodology. If we are to properly evaluate philosophical methods vis-a-vis their use of something called intuitions { if we are to assess the empirical challenge { it is important to be clear exactly what we mean by `intuitions'. Part II focuses on this. Chapter 6 argues there is little consensus among philosophers as to what intuitions are and their role in philosophy. Chapter 7 questions whether philosophers have developed an idiolect in which `intuition' has distinctive meaning | as frequently supposed. Chapter 8 points out a common misunderstanding about intuitions in philosophy; using quantitative tools to challenge the idea that an increased use of `intuition' in philosophy is the result of an increased use of intuition. So, the developing picture is one of confusion, without a clear idea of what sense of `intuition' is important. Fortunately, Chapter 9 sets us back on the right track. It sets out a positive programme for evaluative methodology: methodologists should adopt a permissive conception of intuitions and make fine distinctions between different intuitions, so long as we can track those distinctions while philosophising.