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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

CP violation and supersymmetry-breaking in superstring models

Dent, Thomas Edward January 2000 (has links)
No description available.
42

Design Considerations for Monopile Founded Offshore Wind Turbines Subject to Breaking Waves

Owens, Garrett Reese 1987- 14 March 2013 (has links)
The majority of offshore wind farms utilize monopile substructures. As these wind farms are typically located in water depths less than 30 meters, the effect of breaking waves on these structures is of great concern to design engineers. This research investigation examines many of the practical considerations and alternative ways of estimating breaking wave forces. A survey of existing European wind farms is used to establish a realistic range of basic design parameters. Based upon this information a parametric study was pursued and a series of realistic design scenarios were evaluated. Comparisons include the sensitivity to the wave force model as well as to analytical and numerical wave theories used to evaluate the wave kinematics. In addition, the effect of different kinematics stretching techniques for linear waves is addressed. Establishing whether the bathymetry will induce spilling or plunging wave breaking is critical. Spilling wave breaking can be addressed using existing wave and wave force theories; however for plunging wave breaking an additional impact force must be introduced. Dimensionless design curves are used to display pertinent trends across the full range of design cases considered. This research study provides insight into the evaluation of the maximum breaking wave forces and overturning moment for both spilling and plunging breaking waves as a function of bottom slope.
43

Transient impressions : designing breaking and changing textile expressions

TALMAN, RIIKKA January 2014 (has links)
'Transient impressions' explores breaking and changing qualities in textiles. Sustainability and people’s relationship to textiles are discussed through decomposing and changing processes in textile material and through different life-spans of materials. The project proposes a way of working with textile material, where expressions are designed to change over different periods of time. / Program: Konstnärligt masterprogram i mode- oh textildesign
44

Är SJ på rätt spår? : En kvalitativ studie om SJs normkritiska reklamkampanj och hur den tas emot av två generationer / Is SJ on the right track? : A qualitative study about SJs normbreaking advertising campaign and how it is being received among two generations

Brännström, Sara, Larsson Westin, Amanda January 2019 (has links)
For companies and organizations there's an ongoing battle to maintain reputation, by actively taking a stance in the public debate companies and organizations maintain their position on the market. SJ, Statens Järnvägar, is a Swedish train operating company owned by the Swedish state. In 2017 SJ released the first commercial from their advertising campaign ‘Vem du än är, vart du än ska’ that portray norm-breaking people on their rail travel. The purpose of this essay is to analyze, on the basis of three commercials that are part of SJ's advertising campaign ‘Vem du än är, vart du än ska’ how norms are maintained and challenged through the campaign. The study also aims to investigate how the commercials are being received among younger (22-25 years) and older (58-72 years) age groups, with particular focus on the group's perception of the campaign in relation to norms and corporate responsibility in society. Using tools based in the multimodal analysis we analyzed the commercials and through focus group interviews we gathered thoughts about the commercials from the older and the younger age groups. The theoretical framework based on representation, stereotypes, myths, norms and Corporate Social Responsibility has helped us analyze the commercials and distinguish the respondents thoughts about norms and corporate responsibility. The analysis showed that the respondents understood the message that everyone is welcome to travel with SJ, but they thought the shape of the commercials were weak. Although SJ wants to break norms and stereotypes, we could see that they consolidate certain stereotypes. The respondents stated that they saw a ‘designation’ and meant that by allowing a person to represent a whole group, others within the group may feel designated. The two age groups had similar opinions and we could not determine any major difference based on age. The two age groups did however differ in which subject they discussed most. All respondents expressed how important it was that everyone got a place in the media and that companies have a great responsibility over our social development.
45

Numerical study of two-phase air-water interfacial flow: plunging wave breaking and vortex-interface interaction

Koo, Bon Guk 01 December 2011 (has links)
Two different air-water interfacial flows are studied including plunging wave breaking and flow past a vertical surface-piercing circular cylinder using complementary CFDShip-Iowa version 6 including Cartesian grid solver and orthogonal curvilinear grid solver. The plunging wave-breaking process for impulsive flow over a bump in a shallow water flume has been simulated using the exact experimental initial and boundary conditions. The overall plunging wave breaking process is described with major wave breaking events identified: jet plunge, oblique splash and vertical jet. These major events repeat up to four times before entering the chaotic breaking. The simulations show a similar time line as the experiments consisting of startup, steep wave formation, plunging wave, and chaotic wave breaking swept downstream time phases. Detailed wave breaking processes, including wave profile at maximum height, first plunge, entrapped air bubble trajectories and diameters, kinetic, potential, and total energy, and bottom pressures are discussed along with the experimental results. The simulations show differences and similarities with other experimental and computational studies for wave breaking in deep water and sloping beaches. The geometry and conditions in the present study are relevant to ship hydrodynamics since it includes effects of wave-body interactions and wave breaking direction is opposite to the mean flow. Large-eddy simulation with the Lagrangian dynamic subgrid-scale model has been performed to study the flow past a surface-piercing circular cylinder for Re and Fr effect. The flow features near the air-water interface show significant changes with different Reynolds numbers from sub-critical to critical regime. It is shown that the interface makes the separation point more delayed for all regime of Re. Remarkably reduced separated region below the interface is observed for critical Re regime and it is responsible for much reduced wake and recirculation region behind the cylinder and it recovers in the deep flow. At different Fr, significant changes are shown on the air-water interface structures. At lower Fr, relatively smaller bow waves are observed in front of the cylinder with Kelvin waves behind the cylinder and small amount of free-surface roughness and turbulence are also seen in the wake region. For higher Fr, the bow wave increases remarkably with the larger wake region and deeper depression and it breaks with similar features of plunging breakers. Much more small air-water interface structures including splashes and bubbles are observed behind the cylinder. It is hard to distinguish the Kelvin waves behind the cylinder due to much larger free-surface oscillations and turbulence. As Fr increases, the Kelvin wave angle decreases and deeper and narrower depression region behind the cylinder are observed. The flow features around the cylinder are significantly changed due to this cavity region behind the cylinder.
46

EVALUATING HOMOPHILY AND INCLUSION IN KENTUCKY SECONDARY AGRICULTURE CLASSROOMS THROUGH SOCIAL DISTANCE SCALES

Austin, Ashley C. 01 January 2018 (has links)
This quantitative study considers homophily and inclusion in the secondary agriculture classroom. This study uses social identity and homophily theories to examine classroom culture and how homophily and inclusion impact it. The study aims to use demographic questions and homophily scales to determine whether homophily is occurring in the secondary agriculture classroom and to what extent. This study also uses social distance scales to determine the breaking point or how willing seniors in an agriculture class are to include new students based on the bi-variables of Race, Sexuality, and Social subgroup. The results indicate that homophily and in-group mentality is occurring within Kentucky’s secondary agricultural education classrooms.
47

Short- and Long-Term Trends in Ecological Interactions: From Predator-Prey Interactions to Phanerozoic Diversification

Mondal, Subhronil 10 November 2014 (has links)
During the last two decades, a broad spectrum of short- and long-term studies on different taxonomic groups has enriched our understanding about how dynamics of taxonomic and ecological diversification have changed through geologic time. There are two major issues that have impacted these studies: the quality and quantity of data used are often insufficient in various ways and the methods used may produce results that are more equivocal than supposed. To investigate these issues more fully, this dissertation focuses on studies on two major aspects: 1) short-term studies examining the nature of successful and unsuccessful predatory attacks on Plio-Pleistocene bivalves; and 2) a Phanerozoic-scale project examining trends in bivalve richness and ecological differentiation. The short-term studies, focusing on shell-breaking predation on bivalves, have shown that the existing methodologies which only study either successful or unsuccessful component of predation in isolation are fraught with potential issues in developing effective interpretations. When these two components (i.e., successful and unsuccessful) are studied in tandem as was done here, however, traces of predation can be used to better constrain potential paleoecological interpretations related to predation intensity, predator's attack strategies, and predator-prey dynamics. The long-term project includes two Phanerozoic studies on bivalves' taxonomic and ecological richness. The taxonomic study has shown how the elements included in various datasets used can affect the Phanerozoic richness trajectory of bivalves. The revised and newly compiled dataset developed here reveals that bivalves showed three major episodes of diversification - a Ordovician radiation of orders and families, a Mesozoic diversification of families, and a dramatic Cenozoic rise in the total number of genera - all of which were synchronous with ecological diversification in terms of appearances of new life forms capable of colonizing new ecospace (i.e., cubes). However, these synchronous changes in taxonomic-ecologic richness were influenced by many biotic (e.g., predation, competition, and adaptive innovations) and abiotic (e.g., nutrient availability, sea level, and temperature) components, for which I propose a multilevel mixed model such that all these components can be studied in tandem.
48

Peer Processes and Adolescent Behaviour

Pope, James George January 2008 (has links)
While research suggests that peer influence can lead to increases in undesirable behaviours of adolescents, there has been little focus on the specific mechanisms of influence. A relatively small literature examining social interactions between peers has found that the discussion of rule breaking topics by pairs of boys relates to how much problem behaviour the boys engage in. This research is limited by its reliance on a set of similar samples from a North American population base. This thesis explored the relationship between social interaction and behaviour with sample from New Zealand Aotearoa. Nine pairs of Year 10 boys were recruited primarily from two high schools. A half-hour conversation was video taped for each pair. These conversations were coded on the basis of the nature of the talk between pairs of participants following the coding system proposed by Poe, Dishion, Griesler and Andrews (1990). The coded behaviours were analysed and compared to measures of previous rule breaking behaviours. The duration of rule breaking talk was found to correlate with the level of previous rule breaking behaviour. It was not clear whether the amount of rule breaking talk was related to the amount of laughter following it. Possible explanations are discussed. While generalisations from these results are limited by an unexpectedly small sample size, they show similarity to the previous research findings. The findings, the difficulties in recruitment to the research and the implications of these for future research are discussed.
49

Aggressiva barn : -en rapport om barns beteende och pedagogers förhållningssätt

Enghag, Julia January 2010 (has links)
<p>In this report, you will be able to read about how the teacher with the help of others can / should do to support the aggressive pupil towards a more healthy behavior.</p>
50

Equine immobilization with a limb restraint system

Cai, Wei 14 June 2007
Mobility of the horse to initiate motion from the standing position is examined in this thesis. In particular, the thesis focuses on the study of the mobility of a horse with fixed hooves to the ground, and on how its musculoskeletal system is used to free the legs from restraints. Possible leg patterns to initiate motions are investigated. The breaking forces generated at front and hind hooves during static-pulling and dynamic jerking are evaluated. Design of the restraint system that uses ropes to immobilize certain joints in order to prevent the horse from generating these forces is the main objective of this thesis. Such a system could be applied as an alternative to rather massive mechanical devices, the main purpose of which is to block the breaking forces (which are quite large when fully developed).<p> Analysis of the mobility of the horse is based on the mechanics of a skeletal linkage system driven by muscle forces. Only major muscles involved in fighting the restraints are included in the analysis. The force generation capability of a muscle is determined by physiological cross sectional area (PCSA) of the muscle. Possible leg patterns are predicted with the kinematics analysis considering range of motion at each joint in the legs. Corresponding breaking forces generated in each pattern is evaluated with the kinetics analysis. Relationship between the characteristic parameter of the pattern and the breaking force at hoof are established. <p>The horse's computer model is used to justify the analytical result. Fighting mechanisms of the horse are simulated in the dynamic simulation software package. Patterns and the breaking forces developed by the horse model simulation agree well with the analytical results. To the authors best knowledge, this is the first time a computer model is used in analyzing the method of restraining an animal. <p>The mobility of the animal with hoof restraints and methods to remove mobility were further confirmed with a preliminary animal restraint test conducted on a sheep. The sheep was chosen because the leg patterns to initiate motion on a horse are similar to that of sheep, but the sheep is more convenient to handle. The experiment showed that the mobility of the sheep could be removed completely by restraining its hooves, lower legs, and head with easily attached ropes.

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