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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.
391

Language contact and interference in the acquisition of English proficiency by Bantu-speaking students

Wissing, Robin John 11 1900 (has links)
This study analyses the causes of error in the written english of black senior secondary pupils and teacher trainees. Using Error Analysis and Contrastive Analysis in a form known as Interference Analysis and covering a full range of grammatical, syntactical and lexical issues! erroneous items in English are compared with the same items in the learners' first language in order to isolate an identify such errors. Analysis of these errors shows which are due to direct interlingual transfer which are not completely attributable to direct transfer, and which are intralingual, the result of idiosyncratic language usage or merely mistakes rather than errors. While recognizing the degree to which Black learners' language habits have become fossilized and the extent to which standerdized errors form part of the English used by Bantu-speaking students, this study sets out to improve proficiency in English by explaining the the causes of error and by suggesting possible remedial approaches. / English Studies / M.A. (English)
392

Error analysis: investigating the writing of ESL Namibian learners

Mungungu, Saara Sirkka 11 1900 (has links)
This study investigated common English language errors made by Oshiwambo, Afrikaans and Silozi First Language speakers. The study examined errors in a corpus of 360 essays written by 180 participants. Errors were identified and classified into various categories. The four most common errors committed by the participants were tenses, prepositions, articles and spelling. The study is important to educators and study material developers who should become aware of the kind of errors that their target learners make, so that they are in a better position to put appropriate intervention strategies into place. For learners, error analysis is important as it shows the areas of difficulty in their writing. The limitations and some pedagogical implications for future study are included at the end of this research paper. / English Studies / M. A. (TESOL)
393

Estudo metrológico volumétrico de bombas de infusão peristálticas lineares / Volumetric metrological study of peristaltic linear infusion pump

Dumas Junior, Adair 18 August 2016 (has links)
O presente estudo consiste em analisar se o sistema atual de calibração das bombas de um determinado fabricante, baseado na entrada de parâmetros externos e consequente readequação interna por software é adequado para a correção dos volumes infundidos. A literatura carece de estudos sobre bombas de infusão peristálticas lineares, principalmente estudos metrológicos relacionados aos volumes infundidos. Esta carência relaciona-se entre outros fatores, pelos elevados custos das bombas de infusão, bem como à grande quantidade de horas de ensaios necessárias. Para isso, foram analisados os volumes infundidos em taxas mínima, intermediária e máxima de três bombas de infusão peristálticas lineares retiradas aleatoriamente de um hospital no estado do Paraná, que não passavam por manutenção havia exatos doze meses e estavam em uso contínuo no estabelecimento. Foram realizados ensaios em taxa fixa de 25 ml/h em 5 volumes diferentes ao longo da faixa habitual de uso. Também foram feitos ensaios em volume fixo de 10 ml variando-se a taxa de infusão entre 1 ml/h, 25 ml/h e 100 ml/h. Para análise estatística dos resultados, foi feito um teste de normalidade de Anderson-Darling, como a maioria dos resultados não apresentaram características de normalidade, foi feito uma análise do intervalo de confiança das medianas para análise dos resultados. Também foi necessário fazer uma ANOVA para verificação da influência das bombas e das taxas no volume infundido, seguido por uma análise de curva de erros e uma planilha para o cálculo de incertezas das medições. Foi possível verificar que os volumes infundidos pelas bombas deste fabricante, em sua maioria apresentaram mudanças significativas após o processo de calibração, com diminuição na variância e melhora na exatidão dos volumes programados. / This study examined whether the current system calibration of the pumps from a particular manufacturer, based on the input of external parameters and consequent internal readjustment by software, is suitable for the correction of infused volumes. The literature lacks studies on linear peristaltic pump infusion, especially metrological studies related to the infused volume. This deficiency relates among other factors, the high costs of infusion pumps as well as the large amount of hours required for testing. Therefore, the volumes were analyzed by infusing at minimum, intermediate and maximum rates of three linear peristaltic infusion pumps randomly taken from a hospital in the state of Paraná, which had not have maintenance in the latest 12 months and were in continuous use at the hospital. Assays were performed in flat rate of 25 ml / h in 5 different volumes over the usual range of use. Tests at a fixed volume of 10 ml varying the infusion rate at 1 ml/h, 25 ml/h and 100 ml/h were also made. For statistical analysis, an Anderson-Darling normality test was done, as most of the results did not show normal characteristics, an analysis of the confidence interval of the median for analysis of results was done. It was also necessary to do an ANOVA to check the influence of pumps and rates of infused volume, followed by a curve error analysis and a spreadsheet to calculate the measurements uncertainties. It was possible to verify that the volumes infused by the bombs from this manufacturer, at most, showed significant changes after the calibration process, decreasing variance and improving the accuracy of programmed volumes.
394

Estudo metrológico volumétrico de bombas de infusão peristálticas lineares / Volumetric metrological study of peristaltic linear infusion pump

Dumas Junior, Adair 18 August 2016 (has links)
O presente estudo consiste em analisar se o sistema atual de calibração das bombas de um determinado fabricante, baseado na entrada de parâmetros externos e consequente readequação interna por software é adequado para a correção dos volumes infundidos. A literatura carece de estudos sobre bombas de infusão peristálticas lineares, principalmente estudos metrológicos relacionados aos volumes infundidos. Esta carência relaciona-se entre outros fatores, pelos elevados custos das bombas de infusão, bem como à grande quantidade de horas de ensaios necessárias. Para isso, foram analisados os volumes infundidos em taxas mínima, intermediária e máxima de três bombas de infusão peristálticas lineares retiradas aleatoriamente de um hospital no estado do Paraná, que não passavam por manutenção havia exatos doze meses e estavam em uso contínuo no estabelecimento. Foram realizados ensaios em taxa fixa de 25 ml/h em 5 volumes diferentes ao longo da faixa habitual de uso. Também foram feitos ensaios em volume fixo de 10 ml variando-se a taxa de infusão entre 1 ml/h, 25 ml/h e 100 ml/h. Para análise estatística dos resultados, foi feito um teste de normalidade de Anderson-Darling, como a maioria dos resultados não apresentaram características de normalidade, foi feito uma análise do intervalo de confiança das medianas para análise dos resultados. Também foi necessário fazer uma ANOVA para verificação da influência das bombas e das taxas no volume infundido, seguido por uma análise de curva de erros e uma planilha para o cálculo de incertezas das medições. Foi possível verificar que os volumes infundidos pelas bombas deste fabricante, em sua maioria apresentaram mudanças significativas após o processo de calibração, com diminuição na variância e melhora na exatidão dos volumes programados. / This study examined whether the current system calibration of the pumps from a particular manufacturer, based on the input of external parameters and consequent internal readjustment by software, is suitable for the correction of infused volumes. The literature lacks studies on linear peristaltic pump infusion, especially metrological studies related to the infused volume. This deficiency relates among other factors, the high costs of infusion pumps as well as the large amount of hours required for testing. Therefore, the volumes were analyzed by infusing at minimum, intermediate and maximum rates of three linear peristaltic infusion pumps randomly taken from a hospital in the state of Paraná, which had not have maintenance in the latest 12 months and were in continuous use at the hospital. Assays were performed in flat rate of 25 ml / h in 5 different volumes over the usual range of use. Tests at a fixed volume of 10 ml varying the infusion rate at 1 ml/h, 25 ml/h and 100 ml/h were also made. For statistical analysis, an Anderson-Darling normality test was done, as most of the results did not show normal characteristics, an analysis of the confidence interval of the median for analysis of results was done. It was also necessary to do an ANOVA to check the influence of pumps and rates of infused volume, followed by a curve error analysis and a spreadsheet to calculate the measurements uncertainties. It was possible to verify that the volumes infused by the bombs from this manufacturer, at most, showed significant changes after the calibration process, decreasing variance and improving the accuracy of programmed volumes.
395

Numerical Quality and High Performance In Interval Linear Algebra on Multi-Core Processors / Algèbre linéaire d'intervalles - Qualité Numérique et Hautes Performances sur Processeurs Multi-Cœurs

Theveny, Philippe 31 October 2014 (has links)
L'objet est de comparer des algorithmes de multiplication de matrices à coefficients intervalles et leurs implémentations.Le premier axe est la mesure de la précision numérique. Les précédentes analyses d'erreur se limitent à établir une borne sur la surestimation du rayon du résultat en négligeant les erreurs dues au calcul en virgule flottante. Après examen des différentes possibilités pour quantifier l'erreur d'approximation entre deux intervalles, l'erreur d'arrondi est intégrée dans l'erreur globale. À partir de jeux de données aléatoires, la dispersion expérimentale de l'erreur globale permet d'éclairer l'importance des différentes erreurs (de méthode et d'arrondi) en fonction de plusieurs facteurs : valeur et homogénéité des précisions relatives des entrées, dimensions des matrices, précision de travail. Cette démarche conduit à un nouvel algorithme moins coûteux et tout aussi précis dans certains cas déterminés.Le deuxième axe est d'exploiter le parallélisme des opérations. Les implémentations précédentes se ramènent à des produits de matrices de nombres flottants. Pour contourner les limitations d'une telle approche sur la validité du résultat et sur la capacité à monter en charge, je propose une implémentation par blocs réalisée avec des threads OpenMP qui exécutent des noyaux de calcul utilisant les instructions vectorielles. L'analyse des temps d'exécution sur une machine de 4 octo-coeurs montre que les coûts de calcul sont du même ordre de grandeur sur des matrices intervalles et numériques de même dimension et que l'implémentation par bloc passe mieux à l'échelle que l'implémentation avec plusieurs appels aux routines BLAS. / This work aims at determining suitable scopes for several algorithms of interval matrices multiplication.First, we quantify the numerical quality. Former error analyses of interval matrix products establish bounds on the radius overestimation by neglecting the roundoff error. We discuss here several possible measures for interval approximations. We then bound the roundoff error and compare experimentally this bound with the global error distribution on several random data sets. This approach enlightens the relative importance of the roundoff and arithmetic errors depending on the value and homogeneity of relative accuracies of inputs, on the matrix dimension, and on the working precision. This also leads to a new algorithm that is cheaper yet as accurate as previous ones under well-identified conditions.Second, we exploit the parallelism of linear algebra. Previous implementations use calls to BLAS routines on numerical matrices. We show that this may lead to wrong interval results and also restrict the scalability of the performance when the core count increases. To overcome these problems, we implement a blocking version with OpenMP threads executing block kernels with vector instructions. The timings on a 4-octo-core machine show that this implementation is more scalable than the BLAS one and that the cost of numerical and interval matrix products are comparable.
396

Análise das dificuldades enfrentadas por alunos do ensino médio em interpretar e resolver problemas de matemática financeira

Fonseca, Simone de Jesus da 31 May 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This research had the purpose to identify students' difficulties in the financial mathematics problem solving as well, analyze the mistakes made by them. The study involved 39 students of the 3rd year in high school of a state school at the Sergipano High Hinterland. The data collection included the application of two questionnaires with four questions each, both involving the same Financial Mathematics subjects. For the analysis of the first questionnaire was used Error Analysis (Cury 1994) and Movshovitz-Hadar, Zaslavsky and Inbar Model (1986, 1987) quoted by Cury (2007), in order to meet and categorize the types of errors made by the students in the resolution of issues. In the second questionnaire, consisted of problems, we used the qualitative analysis and the phases considered by Polya (1995) to solve problems. From this perspective, we tried to identify the stage that presents itself as the most difficulties of students in problem solving. In the analysis of the first questionnaire, we detected that the biggest difficulty faced is related to technical errors, errors involving calculations and algebraic manipulations. This showed us how the deficit in the operations reflects in the learning of other mathematical content. The second questionnaire proved our mistrust that the greatest difficulty faced by students in problem solving is in the interpretation of the statements. / Esta pesquisa teve o propósito de identificar as dificuldades dos alunos na resolução de problemas em Matemática Financeira bem como, analisar os erros cometidos por eles. O estudo envolveu 39 estudantes do 3º ano do Ensino Médio de um colégio estadual do Alto Sertão Sergipano. A coleta de dados contou com a aplicação de dois questionários com quatro questões cada um, ambos envolvendo os mesmos assuntos de Matemática Financeira. Para a análise do primeiro questionário foi utilizada a Análise de Erros (Cury 1994) e o Modelo de Movshovitz-Hadar, Zaslavsky e Inbar (1986, 1987) citado por Cury (2007), com a finalidade de conhecer e categorizar os tipos de erros cometidos pelos alunos na resolução das questões. Já no segundo questionário, composto por problemas, foi utilizada a análise qualitativa de conteúdo e as fases consideradas por Polya (1995) para a resolução de problemas. Nessa ótica, procuramos identificar a fase que se apresenta como a maior dificuldade dos alunos na resolução de problemas. Na análise do primeiro questionário detectamos que a maior dificuldade enfrentada está relacionada a erros técnicos, que envolvem erros de cálculos e manipulações algébricas. Isso nos mostrou como o déficit nas operações reflete na aprendizagem dos demais conteúdos matemáticos. O segundo questionário comprovou nossa suspeita de que a maior dificuldade enfrentada pelos discentes na resolução de problemas está na interpretação dos enunciados.
397

Preposition and article usage in learner English : An investigation of negative transfer / Användande av prepositioner och artiklar i inlärning av engelska : En undersökning av negativ språköverföring från modersmålet

Almerfors, Håkan January 2018 (has links)
The ways in which someone’s first language (L1) influences his or her second language (L2) to create errors, that is negative transfer, is a topic that has received much attention in the field of Second Language Acquisition (SLA). Previous research has suggested that negative transfer is responsible for many errors. The primary aim of this study is to investigate article and preposition errors in the production of Swedish learners of English and to discuss these errors in relation to negative transfer. The secondary aim is to compare transfer errors by L1 Swedish and L1 Portuguese learners of English.   The first and main part of the study is a corpus investigation of the written production of 80 students in upper secondary school (high school). The second part is a multiple-choice test constructed to provoke transfer errors. It was distributed to students in upper secondary school in Sweden and in Brazil. The results from the corpus analysis are largely in line with those of previous research, for example with regards to how definite article errors are more common than indefinite article errors, and how contexts with definite articles and generic noun phrases seem prone to create transfer errors. The corpus study also shows that substitution was the most common preposition error and that many transfer preposition errors supposedly were caused by direct translations. Through the multiple-choice test, the degree to which the first language had an impact on individual errors could be revealed. All in all, the study reveals several aspects of negative transfer that perhaps a single-language investigation could not, because it is in the comparison of English-learners with different L1s that the most interesting results occur. / De sätt som någons första språk påverkar hans eller hennes andra språk så att fel uppstår, det vill säga negativ språköverföring (negative transfer), är ett ämne som har fått mycket uppmärksamhet inom forskning kring språkinlärning. Tidigare studier har visat på hur negativ språköverföring orsakar många fel. Det primära syftet i denna uppsats är att undersöka artikel- och prepositionsfel i skrift hos svenska elever som lär sig engelska och att diskutera dessa fel i relation till negativ språköverföring. Det sekundära målet är att jämföra hur negativ språköverföring yttrar sig hos svenska och portugisiska elever som lär sig engelska. Den första delen av denna uppsats, som även är huvuddelen, är en korpusundersökning av 80 uppsatser skrivna av högstadieelever. Den andra delen är ett flervalstest som konstruerats för att provocera fram språköverföringsfel. Deltagarna var högstadie- och gymnasieelever från Sverige och Brasilien. Resultaten från korpusundersökningen stämmer i stor utsträckning överens med vad tidigare forskning visat, till exempel att det är vanligare att fel uppstår med bestämda artiklar än med obestämda artiklar och hur bestämda artiklar och tillsammans med generiska nominalfraser tenderar att generera negativ språköverföring. Korpusstudien visar också på hur felaktigt utbyte (substitution) var det vanligaste prepositionsfelet och att många språköverföringsfel förmodligen orsakats av direkta översättningar från svenska. I analysen av resultateten från flervalstestet kunde graden av inflytande från första språket på enskilda fel påvisas. Sammantaget avslöjar undersökningen i denna uppsats på flera aspekter av negativ språköverföring som troligen ej uppenbarats om enkom elever med ett förstaspråk inkluderats, detta eftersom det är i jämförelsen mellan engelska-elever med olika förstaspråk som de mest intressanta resultaten framkommer.
398

A Posteriori Error Analysis of Discontinuous Galerkin Methods for Elliptic Variational Inequalities

Porwal, Kamana January 2014 (has links) (PDF)
The main emphasis of this thesis is to study a posteriori error analysis of discontinuous Galerkin (DG) methods for the elliptic variational inequalities. The DG methods have become very pop-ular in the last two decades due to its nature of handling complex geometries, allowing irregular meshes with hanging nodes and different degrees of polynomial approximation on different ele-ments. Moreover they are high order accurate and stable methods. Adaptive algorithms refine the mesh locally in the region where the solution exhibits irregular behaviour and a posteriori error estimates are the main ingredients to steer the adaptive mesh refinement. The solution of linear elliptic problem exhibits singularities due to change in boundary con-ditions, irregularity of coefficients and reentrant corners in the domain. Apart from this, the solu-tion of variational inequality exhibits additional irregular behaviour due to occurrence of the free boundary (the part of the domain which is a priori unknown and must be found as a component of the solution). In the lack of full elliptic regularity of the solution, uniform refinement is inefficient and it does not yield optimal convergence rate. But adaptive refinement, which is based on the residuals ( or a posteriori error estimator) of the problem, enhance the efficiency by refining the mesh locally and provides the optimal convergence. In this thesis, we derive a posteriori error estimates of the DG methods for the elliptic variational inequalities of the first kind and the second kind. This thesis contains seven chapters including an introductory chapter and a concluding chap-ter. In the introductory chapter, we review some fundamental preliminary results which will be used in the subsequent analysis. In Chapter 2, a posteriori error estimates for a class of DG meth-ods have been derived for the second order elliptic obstacle problem, which is a prototype for elliptic variational inequalities of the first kind. The analysis of Chapter 2 is carried out for the general obstacle function therefore the error estimator obtained therein involves the min/max func-tion and hence the computation of the error estimator becomes a bit complicated. With a mild assumption on the trace of the obstacle, we have derived a significantly simple and easily com-putable error estimator in Chapter 3. Numerical experiments illustrates that this error estimator indeed behaves better than the error estimator derived in Chapter 2. In Chapter 4, we have carried out a posteriori analysis of DG methods for the Signorini problem which arises from the study of the frictionless contact problems. A nonlinear smoothing map from the DG finite element space to conforming finite element space has been constructed and used extensively, in the analysis of Chapter 2, Chapter 3 and Chapter 4. Also, a common property shared by all DG methods allows us to carry out the analysis in unified setting. In Chapter 5, we study the C0 interior penalty method for the plate frictional contact problem, which is a fourth order variational inequality of the second kind. In this chapter, we have also established the medius analysis along with a posteriori analy-sis. Numerical results have been presented at the end of every chapter to illustrate the theoretical results derived in respective chapters. We discuss the possible extension and future proposal of the work presented in the Chapter 6. In the last chapter, we have documented the FEM codes used in the numerical experiments.
399

¿Qué has aprendido hoy? : Una comparación entre los temas dados y los conocimientos adquiridos en clase de ELE del 1°, 3° y 4° nivel en un centro de educación secundaria postobligatoria en Suecia

Lindberg, Manuel January 2015 (has links)
Lately most investigations regarding Swedish students’ level in Spanish as a foreign language indicate that there is a notable gap in their linguistic knowledge. It is possible to give various explanations to this tendency, such as the capacity of the educators or the level of motivation the students have. These explications, however, does not explain the fact that this is a problem on a national level. In order to be part of the search to find a potential solution to this issue this investigation has been made with the intention of assessing whether the students truly learn what they are being taught, by means of a modified error analysis, in which there it has also been investigated what part of the Spanish language that seems to be the most problematic to learn for the students at a Swedish upper secondary school. Last but not least this study also attempts to look into the possible influences of the first language and the gender of the learners. The error analysis that has been used consists in a test that contains twelve sentences, of which six are incorrect. All the sentences were based on constituents of the Spanish language that had already been studied in class. The students who participated in this study, all of them at the first, third and fourth level in the curriculum established by Swedish National Agency for Education, where asked to identify erroneous sentences and correct them. In this paper it has been proved that the learners, in fact, have failed to learn a considerable part of what they have been taught. It has also been established that neither gender nor native language can be considered relevant factors in the students’ learning ability. As for the most difficult part in the Spanish language it has not been possible to identify a generalizable result, but a few errors that can be found in more than one of the investigated groups, and therefore point out vital problems in the acquisition-process, has been identified. In conclusion, this paper shows that the knowledge of the Swedish students need some improvement, especially when it comes to ensuring that the learners won’t keep making the same mistakes over and over again.
400

Contributions à l'estimation pour petits domaines

Stefan, Marius 26 August 2005 (has links)
Dans la thèse nous nous occupons de l'estimation de la moyenne d'un petit domaine sous un modèle one-fold et utilisant MINQUE pour estimer les composantes de la variance, sous un modèle two-fold avec variances aléatoires, sous des plans noninformatifs et informatifs. / Doctorat en sciences, Orientation statistique / info:eu-repo/semantics/nonPublished

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