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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.
51

An investigation into joyriding as an addictive behaviour

Kellett, Susan K. January 2000 (has links)
This thesis describes an investigation into the type of car crime often referred to as 'joyriding'. Stealing a car for the fun of driving can be carried out quite excessively, and this has led to a number of anecdotal comments that joyriding may be 'addictive'. This has particularly been the case in Northern Ireland, where many joyriders have continued in the behaviour despite the threat or experience of serious paramilitary punishment. However, whilst several studies of car crime have alluded to the suggestion that some joyriders appear to be addicted to the behaviour, research conducted to specifically investigate this phenomenon has been scant. The present study therefore explores this notion further by exploring joyriding within the context of an addiction model. Following 10 pilot interviews with a total of 33 young offenders, the main study consisted of 76 semi-structured interviews conducted with 54 convicted joyriders (aged between 15-21 years), 12 professionals with care and control of joyriders, plus 11 non joyriding young offenders; the sample being drawn from both the Midlands and Northern Ireland. The interviews were transcribed verbatim and a qualitative thematic analysis was undertaken using QSR NUD *IST software. The career of the joyrider is presented in terms of how it maps on to the career pattern of (other) potentially addictive behaviours from initiation through to cessation of the behaviour. Discussion considers how the activity can be understood within the context of a deviant subculture, as well as an investigation of possible dependency to joyriding by some individuals as defined using DSM IV-type criteria. This analysis is followed by a consideration of how notions of `addiction', and 'addiction to joyriding', are perceived by the respondents, and how these notions compare with the 'diagnostic' criteria. Finally, the process of stopping joyriding is discussed within Prochaska and DiClemente's (1984) stages of change model, and related intervention strategies are suggested for the rehabilitation of joyriders at each of the hypothesised stages of change.
52

Environmental Education In The Workplace: Inducing voluntary transport behaviour change to decrease single occupant vehicle trips by commuters into the Perth CBD.

c.baudains@murdoch.edu.au, Catherine Baudains January 2003 (has links)
As populations increase and air quality continues to decline in many cities around the world, there is growing recognition that human dependency on car based transport is a serious pollution issue. The potential exists to change this aspect of human behaviour using environmental education to develop more sustainable transport practices. The application of education strategies to achieve behaviour change in transport mode choice may benefit from an interdisciplinary approach. This research examined the effectiveness of three different educational strategies in a workplace situation in achieving a shift in transport mode away from the single occupant vehicle. This research aimed to determine if workplace based education interventions that stimulate a deeper level of learning, and encourage self-regulated learning and reflective practice, are more likely to achieve positive behaviour change than interventions based on more superficial learning. A secondary aim was to determine if the characteristics or type of workplace influence the effectiveness of particular education strategies. The research focuses specifically on people’s perceptions of transport behaviour and air pollution. The research examined the effectiveness of three workplace based interventions which aimed at reducing the use of single occupant vehicles (SOV) for commuting to work resulting in an increase in the use of green transport (alternatives to the SOV). The primary goal of the three educational interventions was to achieve an increased awareness, development of positive attitudes and increased empowerment regarding sustainable transport choices. Based on a combination of environmental education and self-regulation of learning theory it was theorized that achieving the three afore mentioned educational outcomes would be highly likely to result in a change in behaviour. The three interventions differ in level of participant involvement, while the information and structure of each intervention was controlled as much as is possible in a naturalistic study. The intervention designs were based on educational theories including cognitivist information processing, Vygotskian/social constructivism, and self-regulation of learning. The first intervention provided information to participants impersonally with no additional support. The second intervention incorporated a volunteer to model pro-environmental behaviour, facilitate discussion of issues, and aid in planning commute trips using alternatives to the single occupant vehicle. The third intervention included the formation of a green transport planning group within the workplace which aimed to identify and address barriers to using alternative transport in the workplace through the development of a green transport plan. In the naturalistic workplace setting, mixed methodologies(qualitative and quantitative) were employed to examine the relative effectiveness of the three interventions in terms of participants knowledge about, attitudes towards and behaviour (action) in regard to transport, as well as changes at an organizational level. Multiple case studies and surveys were used to collect data about employee transport behaviour, attitudes, and knowledge in 13 workplaces situated in the central area of Perth, the capital city of Western Australia, before and after a period of intervention. To allow comparability between workplaces in terms of organisational structure and function six of the 13 workplaces were selected to examine in detail,one government and one engineering organization in each of the three intervention groups. It was found that the level of knowledge about car use and air quality was increased in all three intervention groups, suggesting increased involvement does not improve the chance of increasing knowledge. In contrast, significantly more positive attitudes to car use and air quality issues were developed in only the two most involving interventions, suggesting information distribution alone is unlikely to influence attitude. There were no changes in the general environmental attitudes across the intervention groups. Single occupant vehicle trips were significantly reduced in the second intervention group only. An overall significant increase was reported for self efficacy (as a measure of empowerment) but no significant change was reported for any particular intervention group. At an organizational level the third intervention resulted in the greatest organizational change, and it is likely that the measures implemented as a result of the green transport planning process will have an ongoing impact on employee transport behaviour in the participant workplaces. The effectiveness of each intervention type also varied between workplaces. Structural factors such as design of the work environment, internal mail and email systems, and work hours influenced the delivery of the interventions in some workplaces and qualitative data indicates this may have influenced success. There was also an indication that management involvement and workplace culture were major factors influencing participant perceptions of effectiveness of particular education strategies. Overall it is concluded that while the second intervention involving leadership (but without participant ownership) achieved the greatest reduction in use of the single occupant vehicle, the third intervention achieved the greatest long-term impact on participants and organizations. As a result the definition of effectiveness is complicated and is dependant on whether preferred outcomes have a short-term or a long-term focus. These findings have implications for the way in which achieving sustainable transport in metropolitan areas is approached, as well as other environmentally sustainable behaviours.
53

Car distribution organization : strategic issues in four configurations /

Parment, Anders, January 2005 (has links) (PDF)
Diss. Linköping : Linköpings universitet, 2005.
54

Geometric estimation of strains in car body panels

Heap, Graham Stewart January 1988 (has links)
The thesis focuses on the manufacture of car body panels at Austin Rover and in particular the phenomenon of spring-back. After pressing of a shallow drawn panel its shape is often flatter than required. This loss of shape control corresponds to areas of small strains. The aim of the thesis is to describe the generation of a database of small strain information at discrete points on a drawn panel, which could be used in the numerical modelling of the drawing process.
55

An investigation of air motion and heat transfer in a motored indirect injection diesel engine

Tawfig, Mohammed Elmustafa January 1991 (has links)
No description available.
56

Parâmetros reprodutivos de machos da raça Nelore de baixa e alta eficiência alimentar suplementados com ácidos graxos protegidos em pastagem / Reproductive parameters of Nelore males of low and high feed efficiency supplements with protected fatty acids in pasture

Rossi, Guilherme Fazan [UNESP] 26 May 2017 (has links)
Submitted by GUILHERME FAZAN ROSSI null (guilhermemedvet@yahoo.com.br) on 2017-06-22T21:16:10Z No. of bitstreams: 1 TESE_Guilherme_Fazan_Rossi.pdf: 1395035 bytes, checksum: a3fd1af6ee59ed67d9366a19271bc908 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-06-23T17:25:03Z (GMT) No. of bitstreams: 1 rossi_gf_dr_jabo.pdf: 1395035 bytes, checksum: a3fd1af6ee59ed67d9366a19271bc908 (MD5) / Made available in DSpace on 2017-06-23T17:25:03Z (GMT). No. of bitstreams: 1 rossi_gf_dr_jabo.pdf: 1395035 bytes, checksum: a3fd1af6ee59ed67d9366a19271bc908 (MD5) Previous issue date: 2017-05-26 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As dietas enriquecidas com fontes de ácidos graxos poliinsaturados (AGPs) para touros jovens no período da puberdade a maturidade sexual podem exercer efeito positivo no desempenho reprodutivo. Além disso, selecionar animais jovens de melhor eficiência alimentar (baixo consumo alimentar residual - CAR) é muito importante para os programas de melhoramento genético. Dentro desse contexto, o objetivo do presente estudo foi avaliar os parametros reprodutivos de machos jovens da raça Nelore de baixa e alta eficiência alimentar suplementados com ácidos graxos (AGs) protegidos em regime de pastagem. Foram utilizados 48 machos jovens com média de 14,3±0,13 meses de idade e peso de 389,5±5,43 kg. O delineamento experimental foi inteiramente casualisado em arranjo fatorial 2 x 2 (CAR x suplementação) sendo, 24 animais baixo ou negativo CAR com ou sem suplementação com AGs e 24 alto ou positivo CAR com ou sem suplementação com AGs. As dietas experimentais foram isoproteicas. O período de suplementação foi de dezembro à outubro. Os animais foram mantidos em pastagem de capim-marandu, em lotação contínua e taxa de lotação fixa. As mensurações de características de crescimento, de consumo alimentar, concentrações plasmáticas de metabólitos e hormônios, avaliação andrológica e ultrassonografia testicular foram realizadas a cada 28 dias, dos 14 aos 24 meses de idade. A criopreservação espermática foi realizada na última colheita, momento em que os animais apresentavam 24 meses de idade. Após descongelação foram realizados avaliações computadorizadas da cinética espermática (CASA), teste de termorresistência rápido (TTR), integridade da membrana plasmática e acrossomal e produção in vitro de embriões (PIVE). Os dados foram analisados pelo procedimento PROC MIXED do SAS. Os touros de baixo CAR apresentaram peso corporal inicial maior (398,0±5,4) do que os de alto CAR (380,9±5,4) e mantiveram a diferença durante todo o experimento (P<0,05). Os animais que receberam suplementação com AGs protegido apresentaram maiores concentrações plasmática de colesterol, lipoproteína de alta densidade (HDL) e testosterona (161,5±3,2 ng/dL, 67,2±1,6 ng/dL e 12,2±0,6 ng/mL, respectivamente) em relação aos tratamentos sem AGs (124,5±3,2 ng/dL, 57,9±1,6 ng/dL e 10,5±0,6 ng/mL, respectivamente) (P<0,05). Não foram observadas diferenças entre os tratamentos para consumo alimentar, ecotextura testicular, análise do sêmen fresco e PIVE (P>0,05). No entanto, para a avaliação do sêmen pós-descongelação, as velocidade espermáticas (VAP - de trajeto, VSL - em linha reta e VCL - curvilinear; µm/s) analisadas pelo CASA foram maiores para os touros suplementados com AGs protegido (82,6±1,6, 68,6±1,2 e 132,0±3,2 para VAP, VSL e VCL, respectivamente) em relação aos que receberem suplementação sem AGs (76,2±1,6, 64,2±1,2 e 122,3±3,2; VAP, VSL e VCL, respectivamente) (P<0,05). Apesar dessas diferenças de velocidade espermática, coleterol e testosterona sanguínea são necessários avaliações em conjunto com outros testes reprodutivos para determinar a real influência dos AGs na qualidade espermática. / Diets enriched with sources of polyunsaturated fatty acids (PUFAs) for young bulls from puberty to sexual maturity may have a positive effect on reproductive performance. In addition, selecting young animals with better feed intake (low residual feed intake - RFI) is very important for breeding programs. Thus, the aim of this study was to evaluate the reproductive parameters of young Nelore bulls of low and high feed intake supplemented with PUFA in the pasture. The total of 48 young males were used with a 14.3±0.13 months of age and a weight of 389.5±5.43 kg. The experimental design were completely randomized in a factorial 2 x 2 (RFI x supplementation) being 24 animals high RFI with or without supplementation with PUFA and 24 animals low RFI with or without supplementation with PUFA. The diets were isoproteic. The supplementation period was from December to October and the animals were kept in Brachiaria brizantha cv. Marandu pasture in continuous stocking during the experimental period. The measurements of growth characteristics, feed intake, plasma concentrations of metabolites and hormones, andrological evaluation and testicular ultrasonography were performed every 28 days, from 14 to 24 months of age. Sperm cryopreservation was performed it the last collections, at which time the animals were 24 months old. After thawing, computer aided semen analysis (CASA), rapid thermoresistance sperm tests (TTR), integrity of the plasma membrane and acrosomal and in vitro embryo production (IVEP) were performed. The data were analyzed by the SAS procedure PROC MIXED. The low CAR bulls have had higher initial body weight (398.0±5.4) than high CAR (380.9±5.4) and maintained the difference throughout the experiment (P<0.05). The animals that received supplementation with PUFA had higher plasma concentrations of cholesterol, high density lipoprotein (HDL) and testosterone (161.5±3.2 ng/dL, 67.2±1.6 ng/dL e 12.2±0.6 ng/mL, respectively) in relation to treatments without PUFA (124.5±3.2 ng/dL, 57.9±1.6 ng/dL e 10.5±0.6 ng/mL, respectively) (P<0.05). No differences were observed between treatments for feed intake, testicular ecotexture, analysis of fresh semen and IVEP (P>0.05). However, sperm evaluation after thawing, the spermatic velocities (VAP - average path velocity, VSL - straight linear velocity and VCL - curvilinear velocity; μ / s) analyzed y CASA were hi her for bulls supplemented with PUFA (82.6±1.6, 68.6±1.2 e 132.0±3.2 para VAP, VSL e VCL, respectively) in relation for bulls without PUFA (76.2±1.6, 64.2±1.2 e 122.3±3.2; VAP, VSL e VCL, respectively) (P<0,05). Despite these differences in sperm velocity, coleterol and testosterone evaluations are needed in conjunction with other reproductive tests to determine the actual influence of PUFA on sperm quality. / FAPESP: 2013/13696-3
57

Speed and temperature effects in the energy absorption of axially crushed composite tubes

Fontana, Quentin P. V. January 1990 (has links)
Tubes of glass reinforced thermosetting resins have been tested in axial compression between steel platens with one end chamfered to prevent critically high loads causing catastrophic centre failure. By testing in such a manner these tubes crush in a progressive and controlled manner, and are capable of exhibiting high levels of energy absorption, particularly when related to the material mass involved. Polymers are known to display viscoelastic behaviour and polymer composites are similarly sensitive to test speed and temperature. Energy absorption in tube crushing has been shown to be speed and temperature sensitive and the purpose of this project has been to understand the variability of the energy absorption and the associated mechanisms. The main aim has been to show how the two variables interrelate. The materials used have been produced by hot rolling of pre-preg cloth or by resinjection into closed moulds. Reinforcement has consisted of woven glass cloth or random glass mat; matrix materials have been epoxy and polyester resins. Trends to higher values of specific energy absorption with increasing speed have been observed for epoxy matrix tubes, while polyester matrix tubes have shown less certain trends and give lower values of specific energy absorption at high speeds. All the tubes have shown a rapid drop in specific energy absorption with increasing temperature above normal room temperature, with changes in crush mode being very apparent. At temperatures in excess of about 100 degrees C the tubes have failed by centre buckling, the transition temperature from normal crushing to buckling being sensitive to the crush speed. The interrelation between speed and temperature effects has been examined. Three factors that prevent simple interrelation have been identified; these are inertial effects of crush debris, residual stresses in the hoop direction of the tube and frictional heating in the crush zone. Speed sensitivity of the energy absorption has been determined over a range of temperatures and various features of these responses related to the responses of the material properties. Frictional temperature rises have been modelled mathematically and the predictions have been shown to be reasonably consistent with experimental measurements. These temperature rises have been shown to be important in determining the speed sensitive behaviour of the energy absorption levels, particularly for polyester resin matrix tubes tested at high speeds.
58

The Cortisol Awakening Response In Children and Adolescents with a Parental History of Anxiety

Helleman, Amanda January 2016 (has links)
Objective: The current study used a high risk design to investigate whether the Cortisol Awakening Response (CAR) is a potential heritable trait marker of anxiety disorder risk. Method: The sample consisted of 274 healthy offspring (7-18 years old) including 101 offspring with a parental history of panic disorder (PD), generalized anxiety disorder (GAD), or social anxiety disorder (SAD) and 173 offspring with no parental psychopathology. Salivary cortisol was collected at wake-up, 30, and 60 minutes later, as well as at 4pm and 8pm on two consecutive days. The CAR was calculated using area under the curve with respect to ground (AUCg) and increase (AUCi). Correlation analyses of covariates were conducted. Results: No differences between high and low risk groups were detected when the combined sample of high risk offspring was examined. However, when anxiety disorder subtypes were considered, offspring with parental GAD or SAD had a significantly lower CAR and diurnal cortisol response than those with no parental psychopathology. No differences in the CAR or diurnal cortisol were found in offspring with parental PD. Age and puberty status correlated negatively with AUCg and awakening values and anxiety sensitivity correlated positively with AUCg and awakening values. Conclusions: A blunted CAR and diurnal cortisol response may represent a possible heritable risk marker that is specific to GAD or SAD. Further research is needed to confirm these findings. Study results may have important implications in identifying children at risk for anxiety disorders and creating early interventions intended to change the trajectory of risk.
59

Uvedení nového modelu automobilu na trh / Launching of a new car model on the market

Biedermann, Petr January 2008 (has links)
This master thesis is divided into three parts. First part deals with theoretical approaches in marketing strategy with special focus on activities connected to a launch of a new product. These theoretical approaches are compared to common practice in company Renault. Second part focuses on particular case of using marketing strategy -- launching of Renault Koleos model on the Czech market. In the final part of this work we evaluate results of this launch, we try to find weak points and propose corrections of company's marketing strategy.
60

Minimising wheel wear by optimising the primary suspension stiffness and centre plate friction of self-steering bogies

Fergusson, Shelley Nadine 24 February 2010 (has links)
M.Ing. / This report documents the steps taken to gain insight into the dynamics of a HS MkVII self-steering three piece bogie. This was done by firstly studying the dynamics and stability of linear simplifications of the bogie and wagon and then by investigating the dynamics of the bogie by means of a non-linear model.With the necessary insight into the dynamics of the bogie, an optimised relationship between the primary suspension stiffness and the centre plate friction of a self-steering three-piece bogie was achieved. The optimised model’s wear is less than half that of the reference model and has a safe operating speed of 80km/h for an empty wagon and 140 km/h for a loaded wagon. It is recommended that the following be done before issuing a final technical recommendation; • A final optimisation of the lateral and longitudinal primary suspension stiffness arrangement; taking into consideration the physical vertical load bearing capacity of the rubber suspension elements. • A study in order to quantify the effects, on wear, of the increased misaligned position of the bogie on straight track following a curve. A verification of the ADAMS/Rail simulation results by conducting specific on-track tests. • A comprehensive cost-benefit analysis.

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