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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.
81

Error Estimations in the Design of a Terrain Measurement System

Rainey, Cameron Scott 22 March 2013 (has links)
Terrain surface measurement is an important tool in vehicle design work as well as pavement classification and health monitoring. �Non-deformable terrains are the primary excitation to vehicles traveling over it, and therefore it is important to be able to quantify these terrain surfaces. Knowledge of the terrain can be used in combination with vehicle models in order to predict force loads the vehicles would experience while driving over the terrain surface. �This is useful in vehicle design, as it can speed the design process through the use of simulation as opposed to prototype construction and durability testing. �Additionally, accurate terrain maps can be used by highway engineers and maintenance personnel to identify deterioration in road surface conditions for immediate correction. �Repeated measurements of terrain surfaces over an extended length of time can also allow for long term pavement health monitoring. Many systems have been designed to measure terrain surfaces, most of them historically single line profiles, with more modern equipment capable of capturing three dimensional measurements of the terrain surface. �These more modern systems are often constructed using a combination of various sensors which allow the system to measure the relative height of the terrain with respect to the terrain measurement system. �Additionally, these terrain measurement systems are also equipped with sensors which allow the system to be located in some global coordinate space, as well as the angular attitude of that system to be estimated. �Since all sensors return estimated values, with some uncertainty, the combination of a group of sensors serves to also combine their uncertainties, resulting in a system which is less precise than any of its individual components. �In order to predict the precision of the system, the individual probability densities of the components must be quantified, in some cases transformed, and finally combined in order to predict the system precision. �This thesis provides a proof-of-concept as to how such an evaluation of final precision can be performed. / Master of Science
82

What Hinders and Accelerates? : A Study of Sustainable Electric Mobility Transitions in Sri Lanka / Vad hindrar och accelererar? : En studie av övergången till hållbar mobilitet i Sri Lanka

Bandaranayake, Hasini January 2024 (has links)
The transportation sector is a key carbon emitter, and e-mobility is becoming increasingly recognised around the globe to address climate change, biodiversity loss and societal challenges. In Sri Lanka, e-mobility is identified as a major alternative option that emerged while combating the economic crisis. This paper explores potential pathways to integrate e-mobility into the Colombo Metropolitan Area (CMA) through understanding 'What hinders this e-mobility transition?' and 'How to accelerate it?'. The study applied a combination of transition studies, including MLP, Path dependency and, lock-ins and transition management theories, followed by the mixed-methods approach to analysing the complexities created along the co-evolution of socio-technical systems and to suggest potential pathways. The findings show that historical influences and diverse configuration elements hinder the capabilities of emerging e-mobility novelties by locking society in a private vehicle-dominating regime. A holistic and integrated approach is necessary to overcome the identified challenges and to achieve a sustainable e-mobility transition.
83

Associação do polimorfismo INS-VNTR com a susceptibilidade ao diabetes mellitus tipo 1, tipo 2 e gestacional na população urbana brasileira / Association of the INS-VNTR polymorphism with susceptibility to type 1, type 2 and gestational diabetes mellitus in the urban brazilian population

Pelá, Flávia Porto 19 October 2012 (has links)
O diabetes mellitus (DM) é definido como doença metabólica, caracterizado pela hiperglicemia, causada pela disfunção da secreção de insulina, atividade da insulina ou ambas. É classificado em quatro classes clínicas i) diabetes mellitus tipo 1 (DM1), ii) diabetes mellitus tipo 2 (DM2), iii) diabetes mellitus gestacional (DMG), iv) outros tipos específicos. Dentre os genes conhecidos por influenciarem o mecanismo de produção e liberação de insulina no organismo humano, o gene da insulina (INS) é o mais bem caracterizado nas classes clínicas do DM. A região promotora do gene INS tem sido alvo de estudo em diversas amostras populacionais do mundo, devido a sua capacidade de modular os níveis de expressão de insulina no timo e no pâncreas, de acordo, com a classe alélica que compõe o genótipo do indivíduo. Localizada a 596pb acima do sítio de transcrição do gene da insulina, é estruturada em alelos minissatélites distribuídos in tandem (ACAGGGGTGTGGGG). O alelo classe I (30 - 60 repetições) tem sido associado com predisposição ao DM1, enquanto o alelo classe III (120 - 170 repetições) tem efeito de proteção ao DM1, no entanto, esse alelo tem apresentado correlação ao DM2, à obesidade em crianças e jovens e, aumento de riscos cardiovasculares. O presente trabalho tem como objetivo analisar o polimorfismo da região promotora do gene da insulina sobre os fenótipos do DM e a possível influência desse em características demográficas, clínicas e laboratoriais desses pacientes. Foram analisados 189 pacientes com DM1, 116 pacientes com DM2, 68 pacientes com DMG e 339 indivíduos controle da região de Ribeirão Preto, SP. O DNA genômico foi extraído por salting-out, seguido da amplificação e digestão enzimática do fragmento referente a região promotora do gene INS, o qual contém na sequência downstream, o polimorfismo -23HphI, cujo desequilíbrio de ligação (r2 1) com o polimorfismo INSVNTR, permite inferir os genótipos por intermédio da análise do polimorfismo -23HphI. Observamos que o alelo classe I e o genótipo classe I : classe I estão relacionados à predisposição ao DM1, enquanto o alelo classe III, predominantemente em homozigose, está associado à proteção ao DM1. Em relação ao DM2, o genótipo classe I : classe III foi associado à susceptibilidade a doença e, nenhum genótipo foi correlacionado ao DMG. De acordo com os dados demográficos, clínicos e laboratoriais, variáveis como gênero e pigmentação da pele têm influenciado na frequência do polimorfismo INSVNTR em pacientes com DM1, como por exemplo, a maior frequência de homens com genótipo classe I : classe I no conjunto DM1. Em contrapartida, nesse mesmo grupo de pacientes, o genótipo classe III : classe III evidenciou maior susceptibilidade ao desenvolvimento de retinopatia (p=0,0020; OR= 0,05333; 95% I.C. 0,007839 - 0,3629). Em pacientes com DM2, a comparação entre gêneros evidenciou maior frequência do genótipo classe III : classe III em mulheres. E, em relação ao DMG, os genótipos de classe I : classe I e classe I : classe III estavam associados ao menor nível de glicose no plasma sanguíneo em relação as pacientes que exibiam o genótipo classe III : classe III. Esse é o primeiro estudo de associação do polimorfismo INS-VNTR comparando as três principais classes clínicas de DM oriundas de uma mesma amostra geográfica, sendo evidenciado um perfil genotípico padrão de susceptibilidade de acordo com o tipo de DM. / Diabetes mellitus (DM) is defined as a metabolic disorder characterized by hyperglycemia caused by impaired insulin secretion, insulin activity or both. It is classified into four clinical classes i) type 1 diabetes mellitus (T1DM), ii) type 2 diabetes mellitus (T2DM), iii) gestational diabetes mellitus (GDM), iv) other specific types. Among the genes known to influence the mechanism of production and release of insulin, the insulin gene (INS) has been well characterized in disease susceptibility. The INS promoter has been studied in different worldwide populations due to its ability to modulate expression levels of insulin in the thymus and pancreas, in accordance with the type of diabetes. The major polymorphic site is located 596bp upstream from the translation initiation site of the INS gene and it is structured into minisatellite alleles (ACAGGGGTGTGGGG). The shorter class I alleles (30 60 repeats) confers predisposition to DM1 and the longer class III (120 170 repeats) confers protection to DM1; however, the latter allele has also shown to be correlated with DM2, obesity in children and juvenile individuals, and increased cardiovascular risks. This study aims to analyze the association of a polymorphic site at promoter region of the INS gene with diabetes phenotypes, with the purpose of evaluating this region as a possible genetic marker of the disease, and the possible influence on demographic, clinical and laboratory features in a sample of the urban Brazilian population. We analyzed 189 T1DM patients, 116 T2DM patients, 68 GDM patients and 339 healthy individuals from the region of Ribeirão Preto, SP. DNA extraction was performed using a salting-out procedure, followed by amplification and restriction enzyme digestion of the fragment relating to INS gene promoter, which contains another polymorphism, -23HphI, which is in perfect linkage disequilibrium (r2 1) with the INS-VNTR, making it an useful genetic marker. We observed that the class I allele and class I : class I genotype are associated with predisposition to T1DM, whereas, class III allele, predominantly in homozygosity, is associated to T1DM protection. In relation to T2DM, the class I : class III genotype has been associated with susceptibility to disease. Finally, no genotype was correlated with GDM. Data stratification according to demographical, clinical and laboratory variables, indicated that gender, skin color seemed to influence the frequency of the INS-VNTR polymorphism; i. e., the class I : class I genotype was more frequent in male T1DM patients. On the other hand, the presence of the class III : class III genotype was associated with susceptibility the development of retinopathy (p=0,0020; OR= 0,05333; 95% I.C. 0,007839 - 0,3629). In T2DM patients, a trend association was observed between the class III : class III genotype with female diabetic patients. In relation to GDM, the genotypes class I : class I and class I : class III were associated with decreased glucose levels in relation to patients exhibiting the class III : class III genotype. This is the first study of the INS-VNTR polymorphism encompassing the major types if DM patients from the same geographical region, which showed a differential pattern of susceptibility according to the underlying type of DM.
84

Možná asociace polymorfismů v genu pro dopaminový receptor D2 (\kur{DRD2}) s lidským chováním

JANDOVÁ, Linda January 2019 (has links)
This study is focused on the dopamine D2 receptor and the linkage between TaqIA and - 141C Ins/Del polymorphisms in DRD2 gene and novelty seeking behaviour, as well as the linkage between Val158Met polymorphism in COMT gene and novelty seeking behaviour. Novelty seeking behaviour is characterized as a personality trait with a tendency to look for novel stimulation and extravagances at any cost of legal, physical and social risk to reward cues. DRD2 and COMT genes are associated with the function of dopamine, which is essential for motoric function and reward-motivated behaviour. Therefore, the aim of this study is to ascertain the potential linkage among the three studied polymorphisms and novelty seeking behaviour.
85

Erhöhung der Qualität und Verfügbarkeit von satellitengestützter Referenzsensorik durch Smoothing im Postprocessing

Bauer, Stefan 02 February 2013 (has links) (PDF)
In dieser Arbeit werden Postprocessing-Verfahren zum Steigern der Genauigkeit und Verfügbarkeit satellitengestützer Positionierungsverfahren, die ohne Inertialsensorik auskommen, untersucht. Ziel ist es, auch unter schwierigen Empfangsbedingungen, wie sie in urbanen Gebieten herrschen, eine Trajektorie zu erzeugen, deren Genauigkeit sie als Referenz für andere Verfahren qualifiziert. Zwei Ansätze werdenverfolgt: Die Verwendung von IGS-Daten sowie das Smoothing unter Einbeziehung von Sensoren aus der Fahrzeugodometrie. Es wird gezeigt, dass durch die Verwendung von IGS-Daten eine Verringerung des Fehlers um 50% bis 70% erreicht werden kann. Weiterhin demonstrierten die Smoothing-Verfahren, dass sie in der Lage sind, auch unter schlechten Empfangsbedingungen immer eine Genauigkeit im Dezimeterbereich zu erzielen.
86

Associação do polimorfismo INS-VNTR com a susceptibilidade ao diabetes mellitus tipo 1, tipo 2 e gestacional na população urbana brasileira / Association of the INS-VNTR polymorphism with susceptibility to type 1, type 2 and gestational diabetes mellitus in the urban brazilian population

Flávia Porto Pelá 19 October 2012 (has links)
O diabetes mellitus (DM) é definido como doença metabólica, caracterizado pela hiperglicemia, causada pela disfunção da secreção de insulina, atividade da insulina ou ambas. É classificado em quatro classes clínicas i) diabetes mellitus tipo 1 (DM1), ii) diabetes mellitus tipo 2 (DM2), iii) diabetes mellitus gestacional (DMG), iv) outros tipos específicos. Dentre os genes conhecidos por influenciarem o mecanismo de produção e liberação de insulina no organismo humano, o gene da insulina (INS) é o mais bem caracterizado nas classes clínicas do DM. A região promotora do gene INS tem sido alvo de estudo em diversas amostras populacionais do mundo, devido a sua capacidade de modular os níveis de expressão de insulina no timo e no pâncreas, de acordo, com a classe alélica que compõe o genótipo do indivíduo. Localizada a 596pb acima do sítio de transcrição do gene da insulina, é estruturada em alelos minissatélites distribuídos in tandem (ACAGGGGTGTGGGG). O alelo classe I (30 - 60 repetições) tem sido associado com predisposição ao DM1, enquanto o alelo classe III (120 - 170 repetições) tem efeito de proteção ao DM1, no entanto, esse alelo tem apresentado correlação ao DM2, à obesidade em crianças e jovens e, aumento de riscos cardiovasculares. O presente trabalho tem como objetivo analisar o polimorfismo da região promotora do gene da insulina sobre os fenótipos do DM e a possível influência desse em características demográficas, clínicas e laboratoriais desses pacientes. Foram analisados 189 pacientes com DM1, 116 pacientes com DM2, 68 pacientes com DMG e 339 indivíduos controle da região de Ribeirão Preto, SP. O DNA genômico foi extraído por salting-out, seguido da amplificação e digestão enzimática do fragmento referente a região promotora do gene INS, o qual contém na sequência downstream, o polimorfismo -23HphI, cujo desequilíbrio de ligação (r2 1) com o polimorfismo INSVNTR, permite inferir os genótipos por intermédio da análise do polimorfismo -23HphI. Observamos que o alelo classe I e o genótipo classe I : classe I estão relacionados à predisposição ao DM1, enquanto o alelo classe III, predominantemente em homozigose, está associado à proteção ao DM1. Em relação ao DM2, o genótipo classe I : classe III foi associado à susceptibilidade a doença e, nenhum genótipo foi correlacionado ao DMG. De acordo com os dados demográficos, clínicos e laboratoriais, variáveis como gênero e pigmentação da pele têm influenciado na frequência do polimorfismo INSVNTR em pacientes com DM1, como por exemplo, a maior frequência de homens com genótipo classe I : classe I no conjunto DM1. Em contrapartida, nesse mesmo grupo de pacientes, o genótipo classe III : classe III evidenciou maior susceptibilidade ao desenvolvimento de retinopatia (p=0,0020; OR= 0,05333; 95% I.C. 0,007839 - 0,3629). Em pacientes com DM2, a comparação entre gêneros evidenciou maior frequência do genótipo classe III : classe III em mulheres. E, em relação ao DMG, os genótipos de classe I : classe I e classe I : classe III estavam associados ao menor nível de glicose no plasma sanguíneo em relação as pacientes que exibiam o genótipo classe III : classe III. Esse é o primeiro estudo de associação do polimorfismo INS-VNTR comparando as três principais classes clínicas de DM oriundas de uma mesma amostra geográfica, sendo evidenciado um perfil genotípico padrão de susceptibilidade de acordo com o tipo de DM. / Diabetes mellitus (DM) is defined as a metabolic disorder characterized by hyperglycemia caused by impaired insulin secretion, insulin activity or both. It is classified into four clinical classes i) type 1 diabetes mellitus (T1DM), ii) type 2 diabetes mellitus (T2DM), iii) gestational diabetes mellitus (GDM), iv) other specific types. Among the genes known to influence the mechanism of production and release of insulin, the insulin gene (INS) has been well characterized in disease susceptibility. The INS promoter has been studied in different worldwide populations due to its ability to modulate expression levels of insulin in the thymus and pancreas, in accordance with the type of diabetes. The major polymorphic site is located 596bp upstream from the translation initiation site of the INS gene and it is structured into minisatellite alleles (ACAGGGGTGTGGGG). The shorter class I alleles (30 60 repeats) confers predisposition to DM1 and the longer class III (120 170 repeats) confers protection to DM1; however, the latter allele has also shown to be correlated with DM2, obesity in children and juvenile individuals, and increased cardiovascular risks. This study aims to analyze the association of a polymorphic site at promoter region of the INS gene with diabetes phenotypes, with the purpose of evaluating this region as a possible genetic marker of the disease, and the possible influence on demographic, clinical and laboratory features in a sample of the urban Brazilian population. We analyzed 189 T1DM patients, 116 T2DM patients, 68 GDM patients and 339 healthy individuals from the region of Ribeirão Preto, SP. DNA extraction was performed using a salting-out procedure, followed by amplification and restriction enzyme digestion of the fragment relating to INS gene promoter, which contains another polymorphism, -23HphI, which is in perfect linkage disequilibrium (r2 1) with the INS-VNTR, making it an useful genetic marker. We observed that the class I allele and class I : class I genotype are associated with predisposition to T1DM, whereas, class III allele, predominantly in homozygosity, is associated to T1DM protection. In relation to T2DM, the class I : class III genotype has been associated with susceptibility to disease. Finally, no genotype was correlated with GDM. Data stratification according to demographical, clinical and laboratory variables, indicated that gender, skin color seemed to influence the frequency of the INS-VNTR polymorphism; i. e., the class I : class I genotype was more frequent in male T1DM patients. On the other hand, the presence of the class III : class III genotype was associated with susceptibility the development of retinopathy (p=0,0020; OR= 0,05333; 95% I.C. 0,007839 - 0,3629). In T2DM patients, a trend association was observed between the class III : class III genotype with female diabetic patients. In relation to GDM, the genotypes class I : class I and class I : class III were associated with decreased glucose levels in relation to patients exhibiting the class III : class III genotype. This is the first study of the INS-VNTR polymorphism encompassing the major types if DM patients from the same geographical region, which showed a differential pattern of susceptibility according to the underlying type of DM.
87

Multiple Hypothesis Testing Approach to Pedestrian Inertial Navigation with Non-recursive Bayesian Map-matching

Koroglu, Muhammed Taha 22 September 2020 (has links)
No description available.
88

Weigh-in Environment and Weight Intentionality and Management of Female Collegiate Athletes

Tackett, Bailey 12 1900 (has links)
Research suggests that female athletes, in particular, experience “sport-environment” pressures such as: weight, performance, and body image demands from their coaches, teammates, and judges. These influences in tandem with society’s portrayal of the thin ideal are thought to considerably increase the risk of developing disordered eating problems in this population. Although numerous studies have been conducted over the past decade on the prevalence of eating disorders and pathogenic weight control behaviors among female athletes, few have examined in detail the weight pressures that exist within the sport environment, such as whether or not (and how often) athletes are weighed by their coaches, and how athletes respond to those pressures in terms of weight management practices. In the proposed study, we will examine the weigh-in environment, weight satisfaction, weight management practices, menstrual health, and reported source of nutritional guidance. The sample includes 414 NCAA Division I female collegiate swimmers/divers and gymnasts drawn from 26 universities across the U.S. Participants anonymously completed a series of questionnaires as part of a larger study on student-athlete health and well-being. This study found that 41% of athletes were weighed, and most often by an athletic trainer in private. Despite most weigh-ins were reportedly conducted in a positive manner, the majority of the athletes who were weighed (75%) reported using at least one strategy to manage their weight prior to weigh-ins (e.g. restrict food, increase exercise). Athletes desire to lose weight, caloric intake, and menstrual cycles were not related to whether athletes were or were not weighed. The majority of athletes received qualified nutritional guidance about how to healthfully manage their weight. Overall, weighing is occurring in a more positive manner than expected; however, athletes are continuing to report using unhealthy weight management strategies at a high rate. It seems important for athletic departments to set policies regarding weighing and to continue to provide support and education to coaching and support staff regarding eating disorder identification, referral, and treatment.
89

ALTERNATIVE METHODOLOGIES FOR BORESIGHT CALIBRATION OF GNSS/INS-ASSISTED PUSH-BROOM HYPERSPECTRAL SCANNERS ON UAV PLATFORMS

Tian Zhou (6114419) 10 June 2019 (has links)
<p>Low-cost unmanned aerial vehicles (UAVs) utilizing push-broom hyperspectral scanners are poised to become a popular alternative to conventional remote sensing platforms such as manned aircraft and satellites. In order to employ this emerging technology in fields such as high-throughput phenotyping and precision agriculture, direct georeferencing of hyperspectral data using onboard integrated global navigation satellite systems (GNSS) and inertial navigation systems (INS) is required. Directly deriving the scanner position and orientation requires the spatial and rotational relationship between the coordinate systems of the GNSS/INS unit and hyperspectral scanner to be evaluated. The spatial offset (lever arm) between the scanner and GNSS/INS unit can be measured manually. However, the angular relationship (boresight angles) between the scanner and GNSS/INS coordinate systems, which is more critical for accurate generation of georeferenced products, is difficult to establish. This research presents three alternative calibration approaches to estimate the boresight angles relating hyperspectral push-broom scanner and GNSS/INS coordinate systems. For reliable/practical estimation of the boresight angles, the thesis starts with establishing the optimal/minimal flight and control/tie point configuration through a bias impact analysis starting from the point positioning equation. Then, an approximate calibration procedure utilizing tie points in overlapping scenes is presented after making some assumptions about the flight trajectory and topography of covered terrain. Next, two rigorous approaches are introduced – one using Ground Control Points (GCPs) and one using tie points. The approximate/rigorous approaches are based on enforcing the collinearity and coplanarity of the light rays connecting the perspective centers of the imaging scanner, object point, and the respective image points. To evaluate the accuracy of the proposed approaches, estimated boresight angles are used for ortho-rectification of six hyperspectral UAV datasets acquired over an agricultural field. Qualitative and quantitative evaluations of the results have shown significant improvement in the derived orthophotos to a level equivalent to the Ground Sampling Distance (GSD) of the used scanner (namely, 3-5 cm when flying at 60 m).</p>
90

Defined benefit plan retentions and pension buy-ins/buy-outs : evidence from the UK

Mitrou, Evisa January 2017 (has links)
This thesis consists of three self-contained papers on defined benefit (DB) pension provision in the United Kingdom (UK). In particular, in the first paper, I examine the effect that labour market incentives, managerial incentives and the adoption of FRS17 by UK firms, have on DB plan retention decisions. In this paper, I also examine the role of insider trustees, defined as trustees that are also company executives, on the firm’s decision to keep DB plans open. I find that firms for which human capital is especially important are more likely to retain their defined benefit plans. In addition, CEO and CFO membership in the same pension plan that is provided for other employees positively influences the retention of defined benefit pension plans. Additional analysis using a sub-sample for which data on pension plan trustees are available suggests that being a CEO and a trustee increases the probability of DB plan retentions. Moreover, being a CEO/CFO trustee and a member of the DB plan offered to all employees increases the likelihood of DB plan retention. However, I do not find any evidence that voluntary adoption of FRS 17 influences DB plan retention. In addition, I find that insider-trustees have a positive influence on the decision to maintain DB plans, especially when they are members of these plans. In the second paper, I look at the effect of DB plan retentions and executive membership in them, on corporate credit ratings and the investment and dividend decisions. Empirical findings suggest that firms which continue to sponsor DB plans are more likely to have lower credit ratings which are exacerbated when these plans are underfunded. Despite the above effect however, I find that if the CEO is a member of the DB plan, it positively affects credit ratings. In addition, I find some evidence that the participation of CEOs in the main DB plans in conjunction with overfunded pension plans, negatively affect investment decisions when these schemes remain open. I do not find any association between CEOs membership in the main DB plan and dividend payments which may be explained by the market signalling effects of dividends. Finally, in the third paper, I provide a thorough analysis of the pension buy-in and buy-out market in the UK, and I empirically examine the determinants of such transactions from a firm and plan perspective. I find that firms that implement buy-ins have larger and more funded pension plans, are more profitable and have higher union densities. Moreover, firms that complete buy-outs have larger pension plans and allocate less pension assets in equity. Moreover, the number of employees is negatively associated with both transactions implying it is costlier for firms to conduct either a buy-in or buy-out transaction. While union density is positively associated with buy-ins, it has a negative effect on the likelihood of buy-outs suggesting that unions support buy-in but not buy-out transactions. This may be potentially explained by the fact that the latter are associated with with plan winding-ups.

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