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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.
211

Historical and Projected Eastern Pacific and Intra-Americas Sea TD-Wave Activity in a Selection of IPCC AR5 Models

Serra, Yolande L., Geil, Kerrie 04 1900 (has links)
The tracks of westward-propagating synoptic disturbances across the Intra-Americas Sea (IAS) and far-eastern Pacific, known as easterly waves or tropical depression (TD) waves, are an important feature of the region's climate. They are associated with heavy rainfall events, seed the majority of tropical cyclones, and contribute to the mean rainfall across the region. This study examines the ability of current climate models (CMIP5) to simulate TD-wave activity and associated environmental factors across the IAS and far-eastern Pacific as compared to reanalysis. Model projections for the future are then compared with the historical model experiment to investigate the southward shift in CMIP5 track density and the environmental factors that may contribute to it. While historical biases in TD-wave track-density patterns are well correlated with model biases in sea surface temperature and midlevel moisture, the projected southward shift of the TD track density by the end of the twenty-first century in CMIP5 models is best correlated with changes in deep wind shear and midlevel moisture. In addition, the genesis potential index is found to be a good indicator of both present and future regions of high TD-wave track density for the models in this region. This last result may be useful for understanding the more complex relationship between tropical cyclones and this index in models found in other studies.
212

BIM-Projektering som metod för att minska antalet ÄTA-arbeten inom anläggningsproduktion

Johansson, Pontus, Olander, Pontus January 2016 (has links)
Purpose: BIM has the potential to reduce the number of design errors in construction projects. Possibilities to change parts at a later stage, as well as better opportunities to which the designer himself can detect if anything wrong has been done. The possibility to discover faults easier and with better opportunities for changes should lead to the defects related to design errors in production decreases. The introduction of BIM in a firm may be costly and clear evidence that the design errors decreased by BIM has not been found. The goal of the work is to find out whether the introduction of BIM in the design stage in construction has led to fewer defects related to design errors in the production stage. Method: In order to achieve the target set has interviews with designers at two consulting companies been implemented. This is to find out how the methods of the designing has become more BIM-based. A document analysis has been carried out on the lists of defects and changes from eleven different engineering projects of varying size. These documents come from two large contractors in Sweden. Findings: The deisgners interviewed describe the methods for designing roads and facilities have gone on to become more BIM-based. Having previously designed in 2D CAD it has gone over more to the 3D models. In the 3D software it is also possible to add different models to the same file and check for any errors between them. To check itself has also become easier than when the designing was done in 2D CAD. The lists of changes and defects also shows that the amount of the defects related to design errors was reduced significantly compared to how it looked in a study conducted in 1999 and mentioned in a study from 2014. Implications: The introduction of BIM in the design has led to the defects related to design errors out in production has fallen. This would be of interest to companies thinking of introducing BIM in their organization but have not yet seen the benefits that BIM brings. Limitations: The thesis is relevant to both designers and contractors in civil engineering. This is when the work has been focused more towards the road and facility than designing of houses. Designers and entrepreneurs from different companies in different parts of Sweden have contributed to the collection of data, which means that the results can be assumed to be general. Contact with more companies from more places in Sweden had definitely been able to make the results even more generally. Keywords: BIM, design, changes, design errors / Syfte: BIM har potentialen att minska antalet projekteringsfel i anläggningsprojekt. Möjligheter att ändra delar i ett senare skede samt bättre möjligheter att som projektör själv upptäcka eventuella fel man gjort. Upptäcks fel enklare och med bättre möjligheter för ändringar bör därför leda till att ÄTA-arbetena i produktionen minskar. Att införa BIM på ett företag kan dock vara kostsamt och tydliga bevis på att projekteringsfelen minskat med BIM har inte kunnat hittas. Målet med arbetet var att ta reda på om införandet av BIM i projekteringsskedet vid anläggningsarbeten har lett till färre ÄTA- arbeten relaterade till projekteringsfel ute i produktionsskedet. Metod: För att uppnå det mål som satts har intervjuer med projektörer på två konsultföretag genomförts. Detta för att ta reda på hur metoderna för att projektera blivit mer BIM-baserade. En dokumentanalys har sedan genomförts på ÄTA-listor från elva olika anläggningsprojekt i varierande storlek. Dessa dokument kommer från två större entreprenadföretag i Sverige. Resultat: De projektörer som intervjuats beskriver att metoderna för att projektera vägar och anläggningar har gått mot att bli mer BIM-baserat. Från att tidigare ha projekterat i 2D-CAD har man gått över mer till 3D-modeller. I programmen med 3D finns även möjligheter att lägga in olika modeller i samma fil och kontrollera eventuella fel. Att kontrollera sig själv har även det blivit enklare jämfört med när projektering genomfördes i 2D-CAD. ÄTA-listorna visar även de att mängden ÄTA-arbeten relaterade till projekteringsfel minskat betydligt jämfört med hur det såg ut i en studie genomförd 1999 som även nämns i en studie genomförd 2014. Konsekvenser: Införandet av BIM i projekteringen har lett till att ÄTA-arbetena ute i produktionen har minskat. Detta skulle kunna intressera företag som funderat på att införa BIM i sin organisation men som ännu inte sett nyttan och de fördelar som BIM för med sig. Begränsningar: Examensarbetet är relevant för både projektörer och entreprenörer inom anläggningsbranschen. Detta då arbetet har koncentrerats mer mot väg och anläggning än mot hus. Projektörer och entreprenörer från olika företag i olika delar av Sverige har bidragit till datainsamlingen vilket gör att resultatet kan antas vara generellt. Kontakt med fler företag från fler platser i Sverige hade definitivt kunnat göra resultatet än mer generellt. Nyckelord: BIM, projektering, ÄTA-arbeten, projekteringsfel.
213

Razvoj modela kvantifikovanja rizika u inženjerskom odlučivanju / Risk quantification model development in engineering decision making

Sando Snežana 27 September 2016 (has links)
<p>Budući da rezultati u budućnosti, zavise od odluka u sadašnjosti, ispitivanje uticaja sistematskih grešaka u logici odlučivanja je od velikog značaja. Predmet ovog rada je merenje rizika usled uticaja subjektivnih faktora u procesu procena i donošenja odluka u uslovima neizvesnosti. U dokazivanju hipoteza korišćene su metode klasične i fazi logike. Rezultati istraživanja pokazuju da se kod većine učesnika u proceni indeksa na finansijskim tržištima zemalja u razvoju, uočava uticaj ličnih sklonosti prema preteranom otpimizmu / pesimizmu i preteranom samopouzdanju. Na osnovu rezultata istraživanja predložen je holistički model i alat za buduće procene, koji uzima u obzir koeficijent samopouzdanja kao korektivni faktor u postupku donošenja odluke. Primena modela i alata kao podrška u odlučivanju je moguća kod svih vrsta evaluacija projekata u inženjerskom odlučivanju.</p> / <p>Results in the future depend on decisions in the present. Therefore examination of sistematic errors in logic decision making has high importance. The main objective of this work is risk quantification due to subjective influence in process of evaluation and decison making under uncertainty. The methods which are used are based on classical and fuzzy logic. The research results show that bias toward over opptimism / pessimism and overconfidence in emerging markets stock exchange exist in majority cases. Based on the results of the research are suggested holistic model and tools for future assessment, which take into an account overconfidence coefficient as corective factor in decison making process. The model and tools is possible to use as decision making support for all types of evaluation projects in the engeneering decisions.</p>
214

The Analysis of the Accumulation of Type II Error in Multiple Comparisons for Specified Levels of Power to Violation of Normality with the Dunn-Bonferroni Procedure: a Monte Carlo Study

Powers-Prather, Bonnie Ann 08 1900 (has links)
The study seeks to determine the degree of accumulation of Type II error rates, while violating the assumptions of normality, for different specified levels of power among sample means. The study employs a Monte Carlo simulation procedure with three different specified levels of power, methodologies, and population distributions. On the basis of the comparisons of actual and observed error rates, the following conclusions appear to be appropriate. 1. Under the strict criteria for evaluation of the hypotheses, Type II experimentwise error does accumulate at a rate that the probability of accepting at least one null hypothesis in a family of tests, when in theory all of the alternate hypotheses are true, is high, precluding valid tests at the beginning of the study. 2. The Dunn-Bonferroni procedure of setting the critical value based on the beta value per contrast did not significantly reduce the probability of committing a Type II error in a family of tests. 3. The use of an adequate sample size and orthogonal contrasts, or limiting the number of pairwise comparisons to the number of means, is the best method to control for the accumulation of Type II errors. 4. The accumulation of Type II error is irrespective of distributions.
215

An analysis of health information technology-related adverse events: technology-induced errors and vendor reported solutions

Pequegnat, Victoria 07 August 2019 (has links)
Health information technology has been widely accepted as having the potential to decrease the prevalence of adverse events and improve workflows and communication between healthcare workers. However, the emergence of health technologies has introduced a new type of medical error. Technology-induced errors are a type of medical error that can result from the use of health information technology in all stages of the health information systems life cycle. The purpose of this study is to identify what types of technology-induced errors are present in the key health information technology vendors in the United States, determine if there are any similarities and differences in technology-induced errors present among the key health information technology vendors in the United States, and determine what methods are utilized, if any, by the key vendors of health information technologies to address and/or resolve reported technology-induced errors. This study found that the most commonly reported technology-induced errors are those related to unexpected system behaviours, either through their direct use or through the communication between systems. It was also found that there is a large difference in the number of adverse events being reported by the key health information technology vendors. Just three vendors represent 85% of the adverse events included in this study. Finally, this study found that there are vendors who are posting responses to reported technology-induced errors and these vendors are most commonly following up with software updates and notifications of safety incidents. This study highlights the importance of analyzing adverse event reports in order to understand the types of technology-induced errors that are present in health information technology. / Graduate
216

Evaluation of the effect of the Peer Review Impacts Safety and Medical-errors (PRISM) Program on critical care nurses' attitudes of safety culture and awareness of recovery of medical errors:

Snydeman, Colleen Kirwan January 2017 (has links)
Thesis advisor: Callista Roy / Problem: Nurses act as safety nets, protecting patients from harm through the identification, interruption and recovery of medical errors and adverse events but we need to know more about ways to learn from safety events. This study aimed to address a gap in our understanding of how the PRISM Program affects nurses’ attitudes of safety culture, awareness of the recovery of medical errors, and practice as they relate to patient safety and error prevention. Participants: Critical care nurses in a large academic hospital from intervention (n=95) and control (n=90) units were surveyed pre and post-implementation of the PRISM Program. Intervention unit nurse response rates were 46% pre-survey and 41% post-survey. Control unit nurses' response rates were 38% for pre-survey and 31% for post-survey responses. A total of 42 (44%) intervention unit nurses participated in the PRISM Program. Methods: A pre/post-test design with an intervention and control unit was used to evaluate the effects of the PRISM Program on nurses’ responses on the Safety Attitude Questionnaire (SAQ) and the Recovery of Medical Error Inventory (RMEI) over a three month period. Nurses responded to questions about the impact on their practice. Findings: Analysis demonstrated a significant decrease in the SAQ working conditions post-survey subscale scores and significant findings in the main effects, decreased SAQ subscales: teamwork, job satisfaction, safety climate and perceptions of hospital management. The RMEI did not produce any significant findings. Comments provided insight into some nurses’ participation in the program and the impact on their practice. Implications: A significant decrease in post-survey scores indicate that informed nurses had a more critical view of safety culture and the environment they work in. Nurses expressed a desire to further use surveillance and additional manual checks that placed increased accountability and responsibility for their role in using strategies to keep patient safe and prevent errors and patient harm. / Thesis (PhD) — Boston College, 2017. / Submitted to: Boston College. Connell School of Nursing. / Discipline: Nursing.
217

The Phonic Inventories: Using spelling error patterns to identify children with potential learning difficulties

Grasko, Dina Nicole 19 May 2008 (has links)
The Phonic Inventories are an instrument consisting of three spelling tests. This study explored the potential of this instrument to be used in group administration to identify children with potential learning difficulties. This was done with a sample of full-time mainstream and full-time remedial learners. A repeated measures ANOVA was used to establish if the Phonic Inventories could distinguish the spelling error patterns of learners in different grades for mainstream and remedial. A distinct pattern of key errors was found, which was similar for mainstream and remedial learners. There were performance changes over grade for mainstream learners but not for remedial learners. This suggests the Phonic Inventories may be measuring an underlying spelling ability which progresses in normal learners and not remedial learners. A stepwise regression analysis was used to establish whether the Phonic Inventories predict performance on contrast spelling tests. A good degree of fit was found between the tests, suggesting the Phonic Inventories are measuring the same abilities as other spelling tests, with the advantage of providing additional information. Finally, a discriminant analysis found errors made on the Phonic Inventories to predict group affiliation between the mainstream and remedial group to a good degree. It was concluded that the Phonic Inventories have strong potential as a group administered screening instrument for identifying children with potential learning difficulties.
218

Caracterização mecânica de um robô manipulador paralelo de 3 graus de liberdade. / Mechanical characterization of a parallel manipulator robot with 3 degrees of freedom.

Rinaldi, Decio de Moura 14 May 2018 (has links)
Esta dissertação aborda a caracterização mecânica de um robô manipulador paralelo de 3 graus de liberdade. A topologia do manipulador corresponde a um mecanismo de estrutura cinemática paralela, cujo efetuador é capaz de realizar 3 deslocamentos lineares no espaço tridimensional. A tecnologia associada ao controle de robôs de estrutura cinemática serial encontra-se bastante madura. No entanto, o mesmo não se dá nos robôs paralelos. Para que se avance no domínio do controle de trajetória destes robôs é necessária a sua caracterização mecânica, a qual fornecerá os subsídios para identificação paramétrica, calibração de modelos, ajuste de ganhos dos controladores, etc. Especificamente, a caracterização mecânica neste trabalho teve por objetivo o levantamento experimental dos erros de posicionamento do efetuador com relação a exatidão e repetibilidade, sua rigidez sob a ação de cargas externas, bem como das frequências naturais do sistema. Os ensaios realizados foram executados no robô Laila, que é um protótipo físico de um robô manipulador, desenvolvido pelo Departamento de Engenharia Mecatrônica e Sistemas Mecânicos da Escola Politécnica da Universidade de São Paulo. A dissertação apresenta como resultados os mapeamentos dos erros de posicionamento do efetuador, a rigidez sob a ação de cargas externas, bem como suas frequências naturais, ao longo do espaço de medição. A seguir, apresenta-se uma discussão da consistência dos valores obtidos para estas propriedades. Por fim, é feita uma análise sobre a influência das folgas mecânicas sobre os índices de desempenho do robô. / This dissertation deals with the mechanical characterization of a parallel manipulator robot of 3 degrees of freedom. The topology of the manipulator corresponds to a mechanism of parallel kinematic structure, whose effector is capable of performing 3 linear displacements in the three-dimensional space. The technology associated with the control of robots of serial kinematic structure is quite mature. However, the same is not true of parallel robots. In order to advance in the field of control of trajectory of these robots it is necessary to characterize them mechanically, which will provide the subsidies for parametric identification, calibration of models, adjustment of gains of the controllers, etc. Specifically, the mechanical characterization in this work had as objective the experimental study of the positioning errors of the effector in relation to the accuracy and repeatability, its rigidity under the action of external loads, as well as the natural frequencies of the system. The tests were performed in the Laila robot, which is a physical prototype of a manipulator robot, developed by the Department of Mechatronics Engineering and Mechanical Systems of the Polytechnic School of the University of São Paulo. The dissertation presents as results the mappings of the positioning errors of the effector, the rigidity under the action of external loads, as well as their natural frequencies, along the measurement space. The following is a discussion of the consistency of the values obtained for these properties. Finally, an analysis is made on the influence of the mechanical gaps on the performance indexes of the robot.
219

Sistema de medidas automáticas de vícios de refração ocular. / Automatic measuring system of ocular refractive errors.

Schiabel, Liliane Ventura 24 October 1995 (has links)
Este trabalho tem como finalidade o desenvolvimento de um sistema objetivo e automático de medidas de vícios de refração ocular. Para tanto, a forte interação entre a Física e a Oftalmologia foi de fundamental importância para que o objetivo fosse atingido. Foram desenvolvidos quatro sistemas, dentre os quais, três são completamente distintos entre si no que se refere aos princípios utilizados para a determinação das ametropias oculares, bem como no que se refere ao modo de detecção da luz retro-espalhada pela retina. O quarto sistema é apenas um refinamento do terceiro que se apresentou eficaz para o uso clínico. O terceiro e quarto sistemas, denominados Sistemas DVL-1 e DVL-2, têm como base a projeção com um laser de diodo de um alvo luminoso no fundo do olho do paciente. Os feixes emergentes do olho testado são divididos em seis partes (três meridianos) e são analisados dois a dois por um CCD (linear no caso do sistema DVL-1 e matricial no caso do sistema DVL-2). A distância entre as duas imagens formadas em cada meridiano fornece o poder de refração naquele meridiano. Com os poderes de refração dos três meridianos (0&#176, 120&#176 e 240&#176) é possível determinar o erro refrativo ocular. Testes em réplicas oculares apresentaram uma precisão média de 0,06di (a precisão aceitável para este tipo de exame oftalmológico é de 0,125di) e em olhos in vivo 0,125di para as coordenadas esférica e cilíndrica e 5&#176 para o eixo de astigmatismo, o que está dentro das precisões clínicas necessárias. / The purpose of the present work is the development of an objective and automatic system for ocular refractive errors measurements. Hence, a strong interaction between Physics and Ophthalmology was fundamentally important in order to provide the success of the work four systems have been developed, where three of them are completely different from each other in the sense of the basic principles used for determining the ocular ametropies, as well as for the detection of the scattered light from the retina. System four is just an improvement of system three, which has presented a good efficiency for clinical use purposes. The third and fourth systems, called DVL-1 and DVL-2 systems, consist on projecting a target in the fundus of the tested eye with a diod laser light. The beams which emerge from the tested eye are divided into six portions (three meridians) and are analyzed in pairs by a CCD (linear CCD for DVL-1 and matrix CCD for DVL-2). The distances between the two images in each meridian provide the refractive power in that particular meridian. As the refractive power is obtained for the three meridians (0&#176, 120&#176 e 240&#176), it is possible to determine the ocular refractive error . Tests in artificial eyes have been done and an average error of 0,06di was obtained (0,125di is the allowed precision for this kind of examination). For measurements in vivo eyes a precision of 0,125di for spherical and cylindrical coordinates were obtained, as well as a 5&#176 precision for the axis of astigmatism. These precision values are the ones required by the clinical evaluation.
220

Identification of labelling errors and concerns on specific categories of South African processed food products that may impact consumer health

Van Dyk, Maritza January 2007 (has links)
Thesis (MTech (Consumer Science: Food and Nutrition))--Cape Peninsula University of Technology, 2007 / Labels are the source of information about the contents of food products and must be correct so that consumers are not misled and can make informed product choices. However, food label information is often incorrect, misleading or just insufficient. The aim of this study was to determine the labelling errors and concerns that occurred in specific categories of the South African processed food market. Randomly selected food product labels (N=246) were evaluated that represented the selected categories of processed foods (N=7), namely: breakfast cereal (9%), savoury snacks (13%), sweet snacks (29%), non-refrigerated meals (7%), refrigerated meals (9%), soups and sauces (25%) and convenience desserts and baked goods (8%). A pre-tested labelling checklist was used to evaluate each food label according to the food labelling areas that could impact consumer health considering the current South African labelling regulations published in 1993, the draft of these regulations published in 2002, and the further new proposed draft regulations. Labelling errors found induded the use of prohibited statements and not identifying compound ingredients (19% and 12% of the products respectively). A labelling concern was also the lack of identification of the fatsloils used (61% of the products). Further concerns identified included the lack of additive-free and allergen-free claims. For example, significant differences (p<O.05) were found between the number of products claiming to be aclditive-free and those that could have made such ctaims but did not. A real concern was the listing of ingredients of unknown origin with allergenicity potential (80% of the products). The breakfast cereal category contained the most eneigy and nutrient claims and nutritional education information, with most errors identified in the categories refrigerated meals and soups and sauces, and most concerns in the category savoury snacks. There is scope for food labelling improvement, specifically in the areas of ingredient and allergen identification, additive-free claims and heaJth-related information provision.

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