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1
Su, Yu-Lan. "Cognitive diagnostic analysis using hierarchically structured skills." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/2640.
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This dissertation proposes two modified cognitive diagnostic models (CDMs), the deterministic, inputs, noisy, "and" gate with hierarchy (DINA-H) model and the deterministic, inputs, noisy, "or" gate with hierarchy (DINO-H) model. Both models incorporate the hierarchical structures of the cognitive skills in the model estimation process, and can be used for situations where the attributes are ordered hierarchically. The Trends in International Mathematics and Science Study (TIMSS) 2003 data are analyzed to illustrate the proposed approaches. The simulation study evaluates the effectiveness of the proposed approaches under various conditions (e.g., various numbers of attributes, test lengths, sample sizes, and hierarchical structures). The simulation study attempts to address the model fits, items fit, and accuracy of item parameter recovery when the skills are in a specified hierarchy and varying estimation models are applied. The simulation analysis examines and compares the impacts of the misspecification of a skill hierarchy on various estimation models under their varying assumptions of dependent or independent attributes. The study is unique in incorporating a skill hierarchy with the conventional DINA and DINO models. It also reduces the number of possible latent classes and decreases the sample size requirements. The study suggests that the DINA-H/ DINO-H models, instead of the conventional DINA/ DINO models, should be considered when skills are hierarchically ordered. Its results demonstrate the proposed approaches to analyzing the hierarchically structured CDMs, illustrate the usage in applying cognitive diagnosis models to a large-scale assessment, and provide researchers and test users with practical guidelines.
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Fay, Robert H. "Application of the Fusion Model for Cognitive Diagnostic Assessment with Non-diagnostic Algebra-Geometry Readiness Test Data." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7285.
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This study retrofitted a Diagnostic Classification Model (DCM) known as the Fusion model onto non-diagnostic test data from of the University of Chicago School Mathematics Project (UCSMP) Algebra and Geometry Readiness test post-test used with Transition Mathematics (Third Edition, Field-Trial Version). The test contained 24 multiple-choice middle school math items, and was originally given to 95 advanced 6th grade and 293 7th grade students. The use of these test answers for this study was an attempt to show that by using cognitive diagnostic analysis techniques on test items not constructed for that purpose, highly predictable multidimensional cognitive attribute profiles for each test taker could be obtained. These profiles delineated whether a given test taker was a master or non-master for each attribute measured by the test, thus allowing detailed diagnostic feedback to be disseminated to both the test takers and their teachers.
The full version of the non-compensatory Fusion model, specifically, along with the Arpeggio software package, was used to estimate test taker profiles on each of the four cognitive attributes found to be intrinsic to the items on this test, because it handled both slips and guesses by test takers and accounted for residual skills not defined by the four attributes and twenty-four items in the Q-matrix. The attributes, one or more of which was needed to correctly answer an item, were defined as: Skills— those procedures that students should master with fluency; e.g., multiplying positive and negative numbers; Properties—which deal with the principles underlying the mathematics concepts being studied, such as being able to recognize and use the Repeated-Addition Property of Multiplication; Uses—which deal with applications of mathematics in real situations ranging from routine "word problems" to the development and use of mathematical models, like finding unknowns in real situations involving multiplication; and, Representations—which deal with pictures, graphs, or objects that illustrate concepts.
Ultimately, a Q-matrix was developed from the rating of four content experts, with the attributes needed to answer each item clearly delineated. A validation of this Q-matrix was obtained from the Fusion model Arpeggio application to the data as test taker profiles showed which attributes were mastered by each test taker and which weren’t. Masters of the attributes needed to be acquired to successfully answer a test item had a proportion-correct difference from non-masters of .44, on average. Regression analysis produced an R-squared of .89 for the prediction of total scores on the test items by the attribute mastery probabilities obtained from the Fusion model with the final Q-matrix. Limitations of the study are discussed, along with reasons for the significance of the study.
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Kumazawa, Takaaki. "Systematic criterion-referenced test development in an English-language program." Diss., Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/119394.
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Educational AdministrationEd.D.
Although classroom assessment is one of the most frequent practices carried out by teachers in all educational programs, limited research has been conducted to investigate the dependability and validity of criterion-referenced tests (CRTs). The main purpose of this study is to develop a criterion-referenced test for first-year Japanese university students in a general English program. To this end, four research questions are formulated: (a) To what extent do the criterion-referenced items function effectively?; (b) To what extent do the facets of persons, items, sections, classes, and subtests contribute to the total score variation in two CRT forms?; (c) To what extent are two CRT forms dependable when administered as pretests and posttests?; and (d) To what extent are two CRT forms valid when administered as pretests and posttests? Two CRT forms made up of vocabulary (k = 25), listening (k = 20), and reading (k = 25) subtests were administered to 249 students using a counterbalanced design. Criterion-referenced item analyses showed that most items were working well for criterion-referenced purposes. Both univariate and multivariate generalizability studies indicated that the most of the variance was accounted for by the interaction effect, followed by the items effect, and then by the persons effect. FACETS analyses showed the separation for all the facets accounted for in the analyses and showed that item separation was greater than person separation. This indicated that the students' ability estimates were similar due to their having taken a placement test, whose results were used to form proficiency-based classes. Both univariate and multivariate decision studies indicated that the CRT forms were moderately to highly dependable. The content validity of the CRT forms was supported because the test content was strongly linked to what was taught in class. The construct validity was supported mainly because a fair amount of score gain was observed. This study elucidates how the statistical analyses used in this study can be applied to CRT development, and how CRT development can be carried out as part of curriculum development.
Temple University--Theses
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Chambers, Angela, and not supplied. "Human rights - education and implementation in a commercial organisation." RMIT University. Management, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070207.163032.
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This case study explored the process of incorporating human rights into the operation of an international commercial organisation. Constructing a dialogue to bridge the gap between human rights discourse and commercial realities, this case study identified the unique roles required to develop dialogue and created a model as a diagnostic and educational tool. The roles specific to human rights consulting, of interpreter, Champoin and Enabler afforded effective penetration into the participating industry partner's operational levels. These roles emerged from the process of constructing a human rights discourse and tensions therein where the existing theory of organisational change and consulting was found to be inadequate for human rights intervention. Based on the data of industry partner's existing practices and human rights concerns and on the process of collecting and analysing this data, the model for education and implementation was constructed. It is a flexible tool for examining human rights practices from bottom up as well as top down of an organisation. This research showed that having a comprehensive picture of the complexities involved sas an effective method of exploration and making sense of human rights education and implementation in a multinational industrial setting. The construction of the roles and of the model relied on the central premise of willingness of a multinational corporation to examine its practices and take an autonomous position of corporate citizenship and responsibility. This was consistent with the participatory research design of the study. Theretically this research challenges the appropriateness of traditional organisational change concepts when dealing with human rights; provides a diagnostic and educational tool for human rights consulting; and points to further research in this area.
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Macdonald, George T. "The Performance of the Linear Logistic Test Model When the Q-Matrix is Misspecified: A Simulation Study." Scholar Commons, 2013. https://scholarcommons.usf.edu/etd/5065.
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A simulation study was conducted to explore the performance of the linear logistic test model (LLTM) when the relationships between items and cognitive components were misspecified. Factors manipulated included percent of misspecification (0%, 1%, 5%, 10%, and 15%), form of misspecification (under-specification, balanced misspecification, and over-specification), sample size (20, 40, 80, 160, 320, 640, and 1280), Q-matrix density (60% and 46%), number of items (20, 40, and 60 items), and skewness of person ability distribution (-0.5, 0, and 0.5). Statistical bias, root mean squared error, confidence interval coverage, confidence interval width, and pairwise cognitive components correlations were computed. The impact of the design factors were interpreted for cognitive components, item difficulty, and person ability parameter estimates.
The simulation provided rich results and selected key conclusions include (a) SAS works superbly when estimating LLTM using a marginal maximum likelihood approach for cognitive components and an empirical Bayes estimation for person ability, (b) parameter estimates are sensitive to misspecification, (c) under-specification is preferred to over-specification of the Q-matrix, (d) when properly specified the cognitive components parameter estimates often have tolerable amounts of root mean squared error when the sample size is greater than 80, (e) LLTM is robust to the density of Q-matrix specification, (f) the LLTM works well when the number of items is 40 or greater, and (g) LLTM is robust to a slight skewness of the person ability distribution. In sum, the LLTM is capable of identifying conceptual knowledge when the Q-matrix is properly specified, which is a rich area for applied empirical research.
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Vande, Wiele Philippe. "Higher education for employability : the development of a diagnostic maturity model." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLE004/document.
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Avec les nouvelles réalités économiques et sociales du 21ème siècle dans le contexte de l'émergence de l'économie et de la société du savoir, l'employabilité est devenue un élément majeur de l'agenda politique national et supranational dans le monde entier. De plus, les orientations économiques et sociales de la mondialisation, la mobilité accrue des travailleurs et un accès facilité à l'éducation ont donné lieu à des perspectives de carrière modifiées de sorte que, en ce qui concerne la gestion de carrière, la tâche incombe plutôt à l'individu. L'émergence de l'économie du savoir, notamment, a relancé un débat qui a été latent depuis les années 60 autour de la façon dont les institutions de l'enseignement supérieur contribuent au développement du capital humain nécessaire au progrès social et économique. Même si ceci est reconnu comme un problème depuis des décennies, l'écart entre les besoins du marché du travail actuel et le profil des nouveaux diplômés qui entrent dans le monde du travail semble rester un sujet de discussion.La construction de l'employabilité (notamment la définition du concept d’employabilité) a évolué au cours des dernières décennies. De nombreuses études sur le sujet ont analysé sa nature très complexe et en constante évolution. A ce jour cependant, sa définition souffre encore d'ambiguïté; ce qui complique le développement d’outils efficaces dans le domaine de l'enseignement supérieur, nécessaires à la mise en œuvre et à l’évaluation de mécanismes relatifs à l’employabilité. Dans cette recherche, le concept de l'employabilité est holistique et prend en compte trois paramètres : les facteurs intrinsèques, les facteurs extrinsèques et sa nature actionnable. Cinq thèmes d'activités dans les établissements d'enseignement supérieur ont été identifiés pour traiter efficacement l'employabilité: le curriculum, les services de soutien, les relations avec l’industrie, la mesure de la qualité et le leadership. La conceptualisation holistique et les cinq thèmes formeront la base de la recherche de cette étude qui vise à fournir plus de clarté sur la façon dont l’employabilité peut effectivement être traitée dans le contexte de l'enseignement supérieur et de la façon dont elle peut être évaluée.Suivant une méthodologie de recherche appelée Design Science, à travers une analyse qualitative de trois études de cas soigneusement sélectionnées, un examen approfondi de la littérature et l’application d’une technique Delphi, cette étude aboutit à la proposition finale du développement d’un modèle de développement et de maturité pour l’employabilité « Employability Development and Assessment Maturity Model (EDAMM) » qui fournit un mécanisme de diagnostic validé pour évaluer une institution d’enseignement supérieur dans sa capacité d’offre en termes d’employabilitéIn light of the new economic and societal realities of the 21st Century against the backdrop of the emergence of the knowledge economy and the knowledge society, employability has become a major item on the national and supranational political agenda around the world. Additionally, economic and societal trends of globalization, increased mobility of labour and increased access to education have resulted in changed career perspectives whereby the onus has shifted to the individual in terms of career management. The emergence of the knowledge economy in particular has re-ignited a debate that has been latent since the 60’s around how well Higher Education Institutions deliver on their contribution to the development of the human capital required for societal and economic progress. Even though acknowledged as an issue for decades, the gap between the current labour market requirements and the profile of new graduates that enter the world of work seems to remain a topic of discussion.The construct of employability has evolved over the last few decades whereby extensive studies on the topic have illuminated its highly complex, relative and continuously evolving nature. Up to date however, the construct still suffers from ambiguity around what it is; hence complicating the development of effective Higher Education approaches to address it. For this study the construct of employability will be holistically approached by means of three influencing factors of intrinsic, extrinsic and actionable nature. Five themes of activities in Higher Education Institutions have been identified to hold strong potential to effectively address employability: curriculum, support services, employer engagement, quality measurement and leadership. The holistic conceptualization and the five themes will form the basis of this study’s search for clarity around how employability can effectively be addressed in a Higher Education context and how this can be evaluated.Following a Design Science Research methodology, through a qualitative study of three purposefully sampled case studies, extensive literature review and a Delphi Technique, this study outlines the development towards the final proposal of the Employability Development and Assessment Maturity Model (EDAMM) as a validated diagnostic mechanism to evaluate a Higher Education Institution in its fitness for purpose in terms of employability
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Lin, Ye. "Evaluating mode comparability in early elementary grades." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6604.
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With the widespread use of technology in the assessment field, many testing programs use both computer-based tests (CBTs) and paper-and-pencil tests (PPTs). Both the Standards for Educational and Psychological Testing (AERA, APA, & NCME, 2014) and the International Guidelines on Computer-Based and Internet Delivered Testing (International Test Commission, 2005) have called for studies on the equivalence of scores from different modes to support the uses and interpretations of scores across modes. Studies of administration mode effects, however, are quite limited and have found mixed results in the early childhood literature. In addition, little research has focused on both construct comparability and score comparability.
The purpose of this study was to examine comparability in two stages. The first stage consisted of a series of analyses performed to investigate construct comparability through methods such as Confirmatory Factor Analysis (CFA), Multivariate Analysis of Variance (MANOVA), Classical Test Theory (CTT) and Item Response Theory (IRT). The second stage included summary analyses performed to investigate score comparability by evaluating the means, standard deviations, score distributions and reliabilities for the overall test scores. Correlations between the two modes and Test Characteristic Curves (TCCs) for the two modes were evaluated. Results indicated that, in general, the constructs and scores were comparable between PPTs and CBTs. The item and domain level analysis suggested that several items and domains seemed to be influenced slightly different by mode, while the scores at the total test level were not impacted by mode. This information could be useful for test developers when making decisions about what items to include on both modes.
The current study sought to address gaps in the existing literature. First, this study examined how young test takers perform in a CBT testing environment. This work adds to previous literature in that young test takers have more access to technology than they did when many research studies were previously conducted. Second, this study discussed potential sources of mode effects such as test items and the characteristics of test takers in early elementary grades, another area in which comparability research is lacking. Third, the study evaluated comparability issues in two stages in a comprehensive manner.
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Cavin, Lisa Lyle Combes Bertina H. "Perceptions of importance of diagnostic competencies among educational diagnosticians." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3692.
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Cavin, Lisa Lyle. "Perceptions of importance of diagnostic competencies among educational diagnosticians." Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3692/.
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This research was two-fold in its purpose: the first purpose being to assess the perceived relevance of the current state competency standards adopted in Texas by the State Board for Educator Certification (SBEC) as they apply to the work of the educational diagnostician and the second being to examine the diagnostician's perceived ability of training institutions to prepare professionals for the field of special education evaluation. This study examined the perceptions of educational diagnosticians (N = 432) through the use of a survey instrument. Specifically the survey instrument was designed to assess diagnosticians' perceptions of importance of the SBEC competencies to special education evaluation in general, and to their practice in particular; the frequency with which they use the competencies; and their degree of training to meet the demands of the competencies through their preparatory program. Results indicate variability with regard to the perceived importance of the competencies and the degree of preparation to meet the demands of the competencies in practice.
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Camara, Nathan Joshua. "Life After Disability Diagnosis: The Impact of Special Education Labeling in Higher Education." Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/eps_diss/79.
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There has been an increasing number of students with learning disabilities attending colleges and universities over the past two decades. As a result of federal legislation, institutions of higher education are required through an office of student support services to provide accommodations and modifications for students with disabilities in order to receive federal monies. This semi-structured interview-based qualitative study seeks to understand how four higher education students with disabilities make the choice to “come out” as possessing a learning disability in order to seek academic assistance from the office of student support services. The foundation for this inquiry emerges out of the differences between the medical and social models of disabilities. The framework for the medical model places the individual with a disability as needing to be cured in order to have a normal life, while the social model of disabilities focuses on how society is constructed around able-bodied individuals without substantive consideration for individual differences – specifically disabilities. The data collected were analyzed using a cross-interview analysis of participants’ responses to interview questions. Because little research has been conducted in this content area, the research focused on themes relating to the stigma of disability labels, the choice to come out as possessing a disability, the role of the academic resource center to obtain accommodations and modifications, and the meaning of success for higher education students with disabilities. The stigma associated with possessing a disability while attending an institution of higher education can place additional anxiety on individuals who decide to come out as possessing a disability. The significance of this research to the fields of higher education and disability studies is to gain a better understanding of how the stigma that is associated with students with disabilities affects the manner in which they choose to access student support services and identify themselves as possessing a learning disability. By making the choice to be identified as possessing a disability, students can access academic accommodations and modifications to support academic success, yet the same choice has the potential to have a negative social consequence of being socially labeled as an othered individual. The outcomes for this research study can inform policies and practices relating to the self-identification that students with disabilities must adhere to in order to obtain accommodations and modifications.
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Pachtman, Arnold. "Extraordinary mode absorption at the electron cyclotron harmonic frequencies as a tokamak plasma diagnostic." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/14954.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1986.MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.
Bibliography: leaves 189-192.
by Arnold Pachtman.
Ph.D.
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Chan, Wai-fat. "An investigation into the effects of diagnostic assessment on students' learning : a case study of the effects of diagnostic assessment on secondary 4 students' learning of chemistry /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17601150.
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Frank, Anders. "Gamer mode : Identifying and managing unwanted behaviour in military educational wargaming." Doctoral thesis, KTH, Medieteknik och interaktionsdesign, MID, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156886.
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Games are rule-governed systems at the same time as they are fiction, simulating or representing a real or an abstract world. This defining characteristic may create for different forms of tensions, that is, at different times players may focus on the rules, the fiction or on both during game play. In military education with games, this poses a problem when the learner becomes too focused on the rules, trying to win at any price rather than taking the representation and what it implies in terms of permissible behaviour seriously. In here we attempt to understand how participants in a wargaming situation act out this tension by studying the interaction between the player and the game in military tactical training. The results first of all confirm that there is a tension – there are occasions where players are mainly concerned with winning the wargame, disregarding what the theme is meant to represent. I propose the term gamer mode to refer to this player orientation: players in gamer mode have an extreme rule-focused interaction, meaning they behave rationally with respect to game rules but irrationally with respect to the portrayed real-life situation they are training for. Gamer mode can probably occur for many reasons. This thesis documents two contributing factors. The first concerns whenever the game does not match players’ expectation on mimicking warfare. In these situations players may find that the game breaks the fragile contract of upholding an accurate representation of warfare. The other factor that may lead to gamer mode are game design features such as explicit reward structures or victory conditions. To remedy the situation, the instructor can, in real-time, actively support players’ orientation towards the game and explain in-game events, keeping them on track. When gamer mode occur I argue that the conditions for learning are compromised as the gaming activity becomes its own learning subject, blurring and overshadowing the learning objective. Although the results suggest that gamer mode is mainly detrimental to learning I conclude that gamer mode is a natural way students will approach games and as such, needs to be dealt with by the instructor.QC 20141209
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Higgins, Lesley Ann. "Diagnostic Decision-Making: How Much Do Behavior Rating Scales Influence School Psychologists?" TopSCHOLAR®, 2010. http://digitalcommons.wku.edu/theses/157.
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Behavior rating scales are commonly used as part of the evaluation process throughout the field of psychology. Behavior rating scales help assess social, emotional, and/or behavioral problems in children, adolescents, and teens. Behavior rating scales indicate the severity of problem behaviors compared to a normative sample. Four scenarios were developed that varied scores on a behavior rating scale and the amount of other information that supported a specific diagnosis. A rating of the likelihood of a diagnosis was requested to see how much influence behavior rating scale scores have on diagnostic decision-making. Each of the four scenarios was sent to 200 school psychologists across the country for a total of 800 potential participants. An overall response rate of 37.5% was achieved. The findings revealed that behavior rating scales do have some influence on school psychologists’ diagnostic decision-making. However, school psychologists put more weight on other supporting information, such as classroom observations and teacher and parent reports, than on behavior rating scale scores when making a diagnostic decision.
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Quainoo, James Kobina. "Diagnostic radiography in Ghana : a model for establishing quality standards in professional education and practice in Africa." Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275010.
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Akhenak, Abdelkader. "Conception d'observateurs non linéaires par approche multimodèle : application au diagnostic." Vandoeuvre-les-Nancy, INPL, 2004. http://www.theses.fr/2004INPL114N.
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Les travaux effectués dans le cadre de ce mémoire de thèse concernent la conception d'observateurs non linéaires, robustes vis-à-vis des incertitudes de modèles et d'entrées inconnues. Les méthodes développées portent sur une classe de systèmes non linéaires représentés sous forme multimodèle. Les conditions de stabilité des observateurs proposés sont énoncées en se basant exclusivement sur la deuxième méthode de Lyapunov et sa formulation en termes d'inégalités linéaires matricielles (LMI). Les observateurs synthétisés sont regroupés en deux catégories :• La première consiste a éliminer explicitement l'effet des entrées inconnues (perturbations de nature additive) dans les équations de la dynamique de l'erreur d'estimation. Cette approche trouve ses limites lorsque le multimodèle considéré est sujet à des incertitudes de modèle (perturbations de nature multiplicative). • La seconde catégorie comble les insuffisances précédentes. L'effet des entrées inconnues et des incertitudes de modèles sont, dans ce cas, compensés en introduisant le concept de mode glissant, connu pour sa robustesse vis-à-vis des perturbations citées précédemment, dans la structure des observateurs. Les observateurs développés sont utilisés dans le but de mettre en oeuvre une procédure de détection et localisation de défauts capteurs et actionneurs sur la classe de systèmes non linéaires représentés sous forme multimodèle. Nous avons, transposé et adapté aux multimodèles les méthodes de détection et localisation de défauts développées dans le contexte des modèles linéaires. Une application a été effectuée sur un turboréacteur d'un avion décrit par un multimodèleThe work carried out in this thesis concerns the design of robust nonlinear observers with model uncertainties as weIl as unknown inputs. The developed methods concern a class of a nonlinear systems represented by a multiple model. The stability conditions of the proposed observers are formulated using exclusively the second method of Lyapunov and its formulation in Linear Matrix Inequality (LMI) form. The synthesized observers can be grouped into two categories: The first one is based on explicitly eliminating the effect of the unknown inputs (disturbance of additive nature) in state estimation error. However, this approach is unpractical when the considered multiple model is subject to parametric uncertainty (disturbance of multiplicative nature). The second category attempts to handle the difficulties encountered previously. The underlying principle is to compensate the effects of the different disturbances. This is achieved by introducing the concept of sliding mode, which is robust against the model uncertainties, in the observer structure. The developed observers are used to implement sensor and actuator fault detection and isolation pro- cedure for the class of nonlinear systems represented by a multiple model. For this purpose, we have adapted and transposed the existing fault detection and isolation methods developed in the context of the linear models. The efficiency of the proposed methodology is verified through an interesting application of turbojet engine described by a multiple model
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Ma, Rui. "Recommendations Regarding Q-Matrix Design and Missing Data Treatment in the Main Effect Log-Linear Cognitive Diagnosis Model." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/9043.
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Diagnostic classification models used in conjunction with diagnostic assessments are to classify individual respondents into masters and nonmasters at the level of attributes. Previous researchers (Madison & Bradshaw, 2015) recommended items on the assessment should measure all patterns of attribute combinations to ensure classification accuracy, but in practice, certain attributes may not be measured by themselves. Moreover, the model estimation requires large sample size, but in reality, there could be unanswered items in the data. Therefore, the current study sought to provide suggestions on selecting between two alternative Q-matrix designs when an attribute cannot be measured in isolation and when using maximum likelihood estimation in the presence of missing responses. The factorial ANOVA results of this simulation study indicate that adding items measuring some attributes instead of all attributes is more optimal and that other missing data treatments should be sought if the percent of missing responses is greater than 5%.
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Sorin, Edouard. "Fissuration en modes mixtes dans le bois : diagnostic et évaluation des méthodes de renforcement local." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0264/document.
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Cette thèse s’effectue au sein de l’université de Bordeaux. Ce projet concerne la construction en bois et en particulier la compréhension des phénomènes à l’origine des fissures dans les structures bois. L’un des objectifs étant de concevoir des méthodes efficaces de renforcement local pour les éléments de structure. Pour cela, l’étude se décompose en plusieurs étapes, la compréhension des phénomènes mis en jeu dans la création des fissures sur des bois de construction. Ce travail s’orientera sur la modélisation de fissure en mode mixte, la recherche de solution de renforcement avec compréhension fine de l’impact de types de renforts sur la propagation de la fissure. Cette étude sera accompagnée d’une campagne d’essais, afin de vérifier l’efficacité des renforcements choisis et d’identifier l’impact de l’effet d’échelle sur les modèle de prédiction. Des essais de grandes dimensions seront donc réalisés pour mieux appréhender les effets de groupes et les effets d’échelle sur du matériau d’emploi. On vise ensuite à définir des outils prédictifs de la résistance des systèmes renforcés et de moyens de contrôles pour les Plan d’Assurance QualitéThe purpose of reinforcing assemblies and structural elements inwood is to overcome the resistance limits of the material, by transferring greaterefforts in areas which can lead to premature cracking in structures. The reinforcementsused can be made of steel, composite materials or wood. Their hook can bemechanical (screwed bodies) or by adhesion (structural bonding like glued-in rodsfor example). In both cases, the transfer of solicitations remains poorly known, andthe effect of the beginning and the deflection of crack are not well apprehended. Inengineering techniques, the wood resistance in the reinforced area is neglected, whichis in line with the precautionary principle. Currently, the scientific investigations areinterested in the resistance of those kind of techniques without considering the interactionsbetween the quasi-brittle behavior of the wood and the reinforcementswhich govern the gain in mechanical performance. However, these solutions can leadto a failure caused by the progressive splitting of the wood and the anchor loss ofthe reinforcement. So it seems accurate to propose predictions of the short-termstrength for splitting of reinforced and unreinforced beams, which can be used tofurther exploration of the long-term failure mechanism. That is why, in this study, aglobal prediction model of the ultimate strength of structural components subjectedto splitting, reinforced and unreinforced ones, was developed. It considers the quasibrittlebehavior of the wood and crack propagation in mixed mode, using a mixinglaw established on the R-curves. The relevance of this modeling was then comparedto the current dimensioning methods of the Eurocodes 5, for notched beams, withexperimental campaigns conducted at different scales
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Spencer-scott, Gail M. "Perceptions of Mode Selection of Textbook Delivery across Course Subjects." ScholarWorks, 2015. https://scholarworks.waldenu.edu/dissertations/217.
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Universities are exploring the use of e-books in order to mitigate the high cost of textbooks. The study university was providing both delivery modes to students but was considering adapting to using e-books exclusively. An investigation of users' perceptions on textbook delivery modes had not been conducted at the local site. The purpose of this qualitative case study was to explore the perceptions of students about using e-books and the experiences of textbook directors in the decision-making processes regarding the use of e-books versus textbooks. The Davis' Technology Acceptance Model (TAM) served as the conceptual framework for the study and was used to establish an interview guide. A sample of 12 participants was recruited from the local university in Michigan and was comprised of 5 undergraduate students, 5 graduate students, and 2 textbook directors. For maximum variation, participants were recruited from a variety of courses, while textbook directors were recruited and interviewed based on their roles as university textbook buyers. Individual interviews were conducted and the transcribed data were open coded and analyzed thematically. Results of the data analysis indicated that 6 out of 10 students favored using hard copy textbooks versus e-books for a variety of reasons, while both textbook directors favored providing students with an assortment of delivery modes based on their experiences with student textbook preferences. Implications for positive social change include providing the administration at the local site with data on the perceptions of students regarding the mode of textbook delivery and textbook directors' recommendations for providing both e-books and hard copy texts. Being responsive to students' preferences for learning materials allows for the possibility of improved learning outcomes.
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D'agostino, Maria Antonietta. "Evaluation de l'apport de l'échographie des enthèses (mode B et doppler puissant) au diagnostic de spondylarthrite." Paris 11, 2008. http://www.theses.fr/2008PA11T046.
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CAUDMONT, LAURENT. "Etude de la valeur de l'echographie mode d dans le diagnostic des sinusites maxillaires en reanimation." Saint-Etienne, 1994. http://www.theses.fr/1994STET6427.
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Gregg, Bettylynne F. "Portable responsive instructional materials 1957 to 1982| A historical content analysis using failure mode and effect analysis." Thesis, Northern Illinois University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3723857.
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This historical content analysis study examined portable responsive instructional materials used by United States teachers and students in primary, secondary, and higher education instructional settings for the period of 1957 through 1982—the beginning of the space race with the stimulus of educational funding from the National Defense Education Act (NDEA) to the introduction of classroom computers into the mainstream education population. During this period, a plethora of instructional materials was implemented in classrooms, which supported the audiovisual movement to improve performance and knowledge. This study focused on the pedagogical and functional uses of instructional materials from the specified period of history.
Instructional materials included in this qualitative study provided a response from or feedback to the participant through some form of communication—a screen, display, or other mode of communication. The physical nature of the studied instructional materials was small, lightweight, and portable, and each was used collaboratively or individually for instructional purposes in an educational environment. With this definition in mind, certain materials that were important to the audiovisual movement, such as movie projectors and cameras, were not included in this study. Instructional materials from corporate training were not included in this study with the exception of materials that crossed over from the corporate arena to the educational environment.
Pedagogical and functional frameworks of identified instructional materials from 1957 to 1982 provided a foundation from which to compare contemporary instructional materials and devices to those of the past, to predict pedagogical purposes, and to support current integration of instructional materials such as handheld devices into the classroom based on historical information gathered in this study.
Analysis of the instructional materials was based on audiovisual codes found in the literature of the time. To further analyze the data gathered, a failure mode and effect analysis (FMEA) method was adapted and applied to determine the success or failure of specified functionality of the identified instructional materials.
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Chamseddine, Abbas. "Méthodologie de diagnostic et tolérance aux défauts de systèmes complexes." Aix-Marseille 3, 2007. http://www.theses.fr/2007AIX30048.
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L'objectif de ce travail est de proposer une méthodologie de diagnostic et de tolérance aux défauts appliquée aux systèmes complexes. Dans cette étude, les défauts de capteurs et d'actionneurs sont considérés. Nous traitons également du problème d'instrumentation des systèmes complexes. Dans un premier temps, nous considérons la conception d'un réseau de capteurs minimal (d'un point de vue du nombre des capteurs) vérifiant l'observabilité du système. Le réseau minimal n'est pas robuste vis-à-vis des défauts des capteurs : la perte d'un capteur peut entraîner la perte d'observabilité du système. Nous proposons alors une approche répondant à ce problème. Nous proposons ensuite une méthodologie de conception d'un réseau de capteurs assurant la diagnosticabilité des défauts d'actionneurs des systèmes complexes. Les approches développées sont formulées sous forme de problèmes d'optimisation binaires non linéaires. Elles sont illustrées et validées en simulation sur un modèle réaliste de suspension active du véhiculeThe aim of this work is to propose a methodology of fault diagnosis and fault-tolerant control for complex systems. In this work, both sensor and actuator faults are considered. The problem of complex systems instrumentation is studied. In a first step, we design a minimal number sensor network ensuring the system observability. This minimal number network verifies system's observability but it is not robust in the presence of sensor faults: the breakdown of one sensor may lead to the loss of system's observability. We propose then an approach to design a robust sensor network. Finally, we propose a methodology to design a sensor network ensuring the diagnosability of actuator faults in complex systems. These approaches are formulated as nonlinear binary optimization problems. They are illustrated and validated in simulation using a realistic model of vehicle active suspension
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Baglan, Fuat Onur. "Design Of An Educational Purpose Multifunctional Dc/dc Converter Board." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/2/12610103/index.pdf.
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In this thesis a multifunctional DC/DC converter board will be developed for utilization as an educational experiment set in the switched-mode power conversion laboratory of power electronic courses. The board has a generic power-pole structure allowing for easy configuration of various power converter topologies and includes buck, boost, buck-boost, flyback, and forward converter topologies. All the converters can be operated in the open-loop control mode with a switching frequency range of 30-100 kHz and a maximum output power of 20 W. Also the buck converter can be operated in voltage mode control and the buck-boost converter can be operated in peak-current-mode control for the purpose of demonstrating the closed loop control performance of DC/DC converters. The designed board allows for experimentation on the DC/DC converters to observe the macroscopic (steadystate/ dynamic, PWM cycle and low frequency) and microscopic (switching dynamic) behavior of the converters. In the experiments both such characteristics can be clearly observed such that students at basic learning level (involving only the macroscopic behavior), and students at advanced learning level (additionally involving the parasitic effects) can benefit from the experiments. The thesis reviews the switch mode conversion principles, gives the board design and proceeds with the experiments illustrating the capabilities of the experimental system.
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Lizot, Jean-Philippe. "Intérêt de l'échographie mode B en alternative au scanner dans le diagnostic du comblement du sinus maxillaire chez les patients sous ventilation mécanique suspects de sinusites nosocomiales." Bordeaux 2, 2001. http://www.theses.fr/2001BOR2M002.
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LELIEVRE, ANTOINE. "La maladie de horton : a propos d'une observation particuliere par ses manifestations et par son mode de diagnostic." Amiens, 1988. http://www.theses.fr/1988AMIEM058.
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Chan, Wai-fat, and 陳偉發. "An investigation into the effects of diagnostic assessment onstudents' learning: a case study of theeffects of diagnostic assessment on secondary 4 students' learning ofchemistry." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31958515.
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Sousa, Melo Saulo Leonardo. "The impact on diagnostic yield of the scan mode of cone beam CT images in artificial external root resorption." Thesis, University of Iowa, 2016. https://ir.uiowa.edu/etd/6292.
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Introduction: Root resorption is an undesired but frequent side effect of orthodontic treatment. Several studies have already aimed to evaluate the performance of CBCT on this topic. However, none have addressed the peculiarities of the most common daily orthodontic scenario. The aim of the study was to evaluate the influence of CBCT scans on the diagnosis of artificial external root resorption in the apical third of anterior teeth.
Materials and methods: One hundred extracted human anterior teeth were randomly assigned to 2 uneven groups (51 as the control and 49 as the experimental group). A limited area of the apical third of the root of the teeth of the experimental group was selected and a buffer solution was used to induce tooth subsurface demineralization. Before CBCT image acquisition, each tooth was coated with an approximately 0.3 mm thick layer of utility wax to simulate the radiographic appearance of the periodontal space and placed into an empty mandibular anterior socket of a partially edentulous dry human mandible. The mandible was placed into a polystyrene box filled with water prior to the CBCT examination to simulate soft-tissue attenuation and scattering. The CBCT images were obtained on an i-CAT unit (i-CAT Next Generation, Imaging Sciences International, Hatfield, PA) according to three protocols: (I) half scan (180°), 0.40 mm voxel size; (II) full scan (360°), 0.40 mm voxel size; and (III) full scan (360°), 0.125 mm voxel size. The 300 resultant CBCT DICOM volumes were imported into InVivo software (InVivo5, Anatomage, San Jose, CA) for evaluation by three blinded, previously calibrated observers using a five-point confidence rating scale. Cohen’s kappa was used to calculate observers’ agreement. The diagnostic values of sensitivity (Sn), specificity (Sp) and accuracy (Ac) were performed by pooling observer responses for every image modality. Receiver operating characteristic (ROC) were built and the areas under the curve (AUC) were calculated. The Sn, Sp and Ac values were compared by Cochran’s Q test. The AUC values were compared by Mann-Whitney U test.
Results: The observers’ agreement ranged from 0.63 to 0.71, which was interpreted as a substantial agreement. Protocol III (0.125 mm voxel size) displayed the highest Sn (81.63 %), Ac (80.67%) and AUC (0.807). There were statistically significant differences between protocol III and the other two protocols (p < 0.001). The specificity of protocol I (84.97 %) was greater than that of protocols II (69.93 %) and III (79.74 %); however statistically significant difference was only found between protocols I and II (p = 0.005).
Conclusion: Although there was no difference in accuracy between the degrees of rotation (half and full scan) within the same voxel size (0.4 mm), there was a considerable difference between those and the smallest voxel size (0.125 mm). In fact, it may be suggested that a more dedicated, high resolution scan should be acquired when one intends to investigate the early stage of external root resorption during orthodontic treatment.
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Chiasson, Mary Shannon C. "Site Visitation: School Leaders' Perceptions of a Diagnostic Tool for School Improvement." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1908.
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This case study explored the use of site-visitation as a diagnostic tool for school improvement. Nine charter schools in New Orleans were selected for the study. Based on qualitative research and systems theory, a within- and cross-case analysis of nine semi-structured interviews with school leaders were conducted. The school leaders’ experiences with the state-run site-visitation model and their use of the findings for school improvement was explored. The findings led to the development of a hybrid accountability model that encompasses the components school leaders believe will lead to school improvement. This study aims to assist educators, policy makers, and researchers to better understand site-visitation and its role in school improvement.
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Hinn, D. Michelle. "The Effect of the Major and Minor Mode in Music as a Mood Induction Procedure." Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/31596.
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The effect of major or minor mode in music on the free recall of materials presented in a multimedia setting was investigated. Seventy-seven students from Virginia Polytechnic Institute and State University voluntarily participated in the experiment. The experiment consisted of three Hypercard stacks, identical except for the introduction where participants heard either a major or a minor melody line or no music. Participants read an identical text passage and recalled as much information as they could about the passage afterwards. The results showed no significant difference between groups.Master of Arts
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de, Jesus Roland E. "A diagnostic study of the velocity structure of a meandering jet using a primitive equation model with dynamic mode initialization." Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA240687.
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Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, September 1990.Thesis Advisor(s): Haney, R. L. ; Stanton, T. P. "September 1990." Description based on title screen viewed on December 17, 2009. DTIC Descriptor(s): Ocean currents, *fronts (oceanography), diagnosis(general), California, transitions, theses, mathematical models, vertical orientation. DTIC Identifier(s): California current, CTZ (California transition zone). Author(s) subject terms: Diagnostic model, California Current, CTZ, dynamical modes. Includes bibliographical references (p. 64-66). Also available in print.
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Merheb, Abdel-Razzak. "Diagnostic and fault-tolerant control applied to an unmanned aerial vehicle." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4367/document.
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Les travaux de recherches sur la commande, le diagnostic et la tolérance aux défauts appliqués aux drones deviennent de plus en plus populaires. Il est judicieux de concevoir des lois de commande qui garantissent la stabilité et les performances du drone, non seulement dans le cas nominal, mais également en présence de fortes perturbations et de défauts.Dans cette thèse, un nouvel algorithme bio-inspiré adapté pour la recherche de solutions dans des problèmes d’optimisation est développé. Cet algorithme est utilisé pour trouver les gains des différents contrôleurs conçus pour les drones. La commande par mode glissant est utilisée pour développer deux contrôleurs passifs tolérants aux défauts pour les quadrirotors: un contrôleur par mode glissant augmentée avec un intégrateur, et un contrôleur par mode glissant implémenté en cascade. Parce que les commandes passives ont une robustesse réduite, une commande active par mode glissant est développée. Pour traiter les défauts extrêmes, un contrôleur d’urgence basé sur la conversion du quadrirotor en trirotor est développé. Les commandes actives, passives, et le contrôleur d’urgences sont ensuite intégrés pour former un contrôleur tolérant aux défauts capable de gérer un grand nombre de défaillances tout en garantissant les ressources actionneur et en limitant la charge de calcul du processeur. Finalement, des contrôleurs tolérants aux défauts, actifs et passifs, basés sur des méthodes par mode glissant du premier et deuxième ordre sont développées pour les octorotors. La commande active utilise des méthodes d’allocation de contrôles pour redistribuer les efforts sur les actionneurs sains, réduisant ainsi l’effet du défautUnmanned Aerial Vehicles (UAV) are more and more popular for their civil and military applications. Classical control laws usually show weaknesses in the presence of parameter uncertainties, environmental disturbances, and actuator and sensor faults. Therefore, it is judicious to design a control law capable of stabilizing the UAV not only in the fault-free nominal cases, but also in the presence of disturbances and faults. In this thesis, a new bio-inspired search algorithm called Ecological Systems Algorithm (ESA) suitable for engineering optimization problems is developed. The algorithm is used over the thesis to find optimal gains for the fault tolerant controllers. Sliding Mode Control theory is used to develop two Passive Fault Tolerant Controllers for quadrotor UAVs: Regular and Cascaded SMC. Because Passive Controllers handle a few numbers of faults, an Active Sliding Mode Fault Tolerant Controller using Kalman Filter is developed. To overcome severe faults and failures, an emergency controller based on the Quadrotor-to-Trirotor conversion maneuver is developed. The Controllers developed so far (Passive, Active, and emergency controllers) are then integrated to form the Integrated Fault Tolerant Controller (IFTC). The IFTC is a powerful controller that is able to handle a wide number of faults, and save actuator resources as well as processor computational effort. Finally, Passive and Active Fault Tolerant Controllers are designed for octorotor UAVs based on First Order and Second Order Sliding Mode Control. The AFTC uses Dynamic and Pseudo-Inverse Control Allocation methods to redistribute the control effort among healthy actuators reducing the effect of fault
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Tao, Shuqin. "Using collateral information in the estimation of sub-scores --- a fully Bayesian approach." Diss., University of Iowa, 2009. https://ir.uiowa.edu/etd/321.
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Educators and administrators often use sub-scores derived from state accountability assessments to diagnose learning/instruction and inform curriculum planning. However, there are several psychometric limitations of observed sub-scores, two of which were the focus of the present study: (1) limited reliabilities due to short lengths, and (2) little distinct information in sub-scores for most existing assessments.
The present study was conducted to evaluate the extent to which these limitations might be overcome by incorporating collateral information into sub-score estimation. The three sources of collateral information under investigation included (1) information from other sub-scores, (2) schools that students attended, and (3) school-level scores on the same test taken by previous cohorts of students in that school. Kelley's and Shin's methods were implemented in a fully Bayesian framework and were adapted to incorporate differing levels of collateral information. Results were evaluated in light of three comparison criteria, i.e., signal noise ratio, standard error of estimate, and sub-score separation index. The data came from state accountability assessments.
Consistent with the literature, using information from other sub-scores produced sub-scores with enhanced precision but reduced profile variability. This finding suggests that using collateral information internal to the test has the capability of enhancing sub-score reliability, but at the expense of losing the distinctness of each individual sub-score. Using information indicating the schools that students attended led to a small gain in sub-score precision without losing sub-score distinctness. Furthermore, using such information was found to have the potential to improve sub-score validity by addressing Simpson's paradox when sub-score correlations were not invariant across schools. Using previous-year school-level sub-score information was found to have the potential to enhance both precision and distinctness for school-level sub-scores, although not for student-level sub-scores. School-level sub-scores were found to exhibit satisfactory psychometric properties and thus have value in evaluating school curricular effectiveness. Issues concerning validity, interpretability, suitability of using such collateral information are discussed in the context of state accountability assessments.
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Tounsi, Mohamed. "Cyclage actif en mode MLI des modules de puissance IGBT application des SVM pour le diagnostic des défauts de vieillissement thermique." Caen, 2011. http://www.theses.fr/2011CAEN2082.
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Ce travail porte sur la mise en œuvre d’un classifieur SVM (Séparateur à Vaste Marge) pour le diagnostic automatique de défauts de vieillissement thermique de composants de puissance IGBT à base de mesures électrothermiques. Cela a nécessité le développement d’un banc d’essai de cyclage actif de modules IGBT pour la caractérisation de leur fatigue thermique, l’analyse des dégradations engendrées dans leur assemblage ainsi qu’à la classification de leur mode de fonctionnement, en mode « sain » et en mode « dégradé». La stratégie de cyclage thermique adoptée, vise à reproduite les contraintes imposées aux composants durant un fonctionnement réel. Nous avons suivi d’une part, les paramètres statiques et dynamiques des modules pour détecter d’éventuelles dérives, et d’autre part des paramètres électrothermiques indicateurs de dégradations thermomécaniques dans leur assemblage. Le stress thermique a causé principalement une avance dans les commutations à la fermeture et à l’ouverture ainsi qu’une apparition d’une trainée de courant à l’ouverture. Une analyse de défaillance a permis de révéler un décollement de fils de bonding, une dégradation de la brasure puce/substrat et une reconstruction des surfaces des métallisations d’émetteur et de grille. Le classifieur SVM construit, permet de discerner un mode de fonctionnement dégradé d’un mode de bon fonctionnement des composants, en vue de la mise en œuvre d’une maintenance préventive dans des installations électriques où la continuité de service et la sécurité revêtent une importance capitaleThe work concerns the implementation of an SVM classifier (Support Vector Machine) for an automatic diagnosis of power IGBT module thermal ageing defects, based on thermoelectric measurements. This has required the development of an active cycling test bench for the characterization of the thermal tiredness of IGBT modules, the analysis of the degradations generated in their assembly, and the classification of their operating mode : in " healthy " mode and " degraded " mode. The strategy adopted for the thermal cycling, aims to reproduce the constraints imposed on the components during their real operation. We followed the module static and dynamic parameters in order to detect possible drifts, and thermoelectric parameters used as criteria of thermo-mechanical degradations in their assembly. The thermal stress caused mainly, earlier switching-on and switching-off modes and appearance of a tile-current. A failure analysis has revealed, in the component assembly, bond-wire lift-off, solder layer degradation, and surface dislocation of the gate and emitter metallizations. The implemented SVM classifier, allows to distinguish between an IGBT degraded operating mode and a healthy operating mode, for a preventive maintenance in electric installations where the continuity of service and safety are very important
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Tardif, Manon. "Piégeage et caractérisation de bactéries par cristaux photoniques." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAY054/document.
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La miniaturisation des systèmes de piégeage optique permet la manipulation et l’analyse d’objets de taille nano et micrométrique. Ces objets peuvent être inertes (billes de silice ou de polystyrène, nanotubes de carbones) ou biologiques (virus, bactéries, cellules). Les dispositifs de piégeage intégrés sur puces présentent l’avantage de manipuler des objets uniques de manière réversible et à très faible puissance. Cela en fait des systèmes très adaptés à l’étude des objets biologiques, souvent plus fragiles et traditionnellement étudiés à l’échelle de la population dans les méthodes de microbiologie. Ces travaux de thèse portent sur l’étude de différentes bactéries piégées sur cristaux photoniques 1D et 2D. Nous y démontrons tout d’abord le piégeage de sept espèces bactériennes : E. coli, B. subtilis, S. epidermidis, Y. ruckeri, N. sicca, P. putida et L. innocua. . Nous y décrivons les méthodes de caractérisation spatiale et temporelle développées pour extraire de l’information de ce piégeage sur la taille, la forme, le déplacement et la structure membranaire des bactéries. Un dispositif de piégeage à deux lasers a également été implémenté pour permettre l’analyse fine de l’état d’une bactérie E. coli soumise à un stress thermique. Ces résultats s’inscrivent dans une problématique de diagnostic bactérien, très sensible depuis quelques années avec l’augmentation de la résistance des bactéries aux antibiotiques. Si aucun changement n’intervient, il est prédit que les infections bactériennes constitueront la première cause de mortalité des pays développés d’ici 2050. Il est donc nécessaire d’élaborer de nouveaux outils de diagnostic plus rapides et plus accessibles afin de limiter la distribution abusive d’antibiotiques qui entraine ce phénomène de résistance Nous proposons également en dernière partie de ce manuscrit des solutions pour intégrer notre dispositif de piégeage en vue d’ouvrir la voie à de nouvelles applications dans des environnements pathogènesThe miniaturisation of optical trapping systems allows the manipulation and analysis of nano and micron sized objects. These objects can be inert (silica or polystyrene beads, carbon nanotubes) or biological (viruses, bacteria, cells). Integrated trapping devices on chips have the advantage of handling single objects reversibly and at very low power. This makes them very suitable for the study of biological objects, often more fragile and traditionally studied at the population level in microbiology methods. This work deals with the study of different bacteria trapped on 1D and 2D photonic crystals. We first demonstrate the trapping of seven bacterial species: E. coli, B. subtilis, S. epidermidis, Y. ruckeri, N. sicca, P. putida and L. innocua. . We describe a spatial and temporal characterisation methods developed to extract information from this trapping on the size, shape, motility and membrane structure of bacteria. A trapping device with two lasers has also been implemented to allow the fine analysis of the state of an E. coli bacterium subjected to heat stress. These results falls within the issue of bacterial diagnosis, very sensitive in recent years with the increase of the resistance of bacteria to antibiotics. If no change occurs, it is predicted that bacterial infections will be the main cause of death in developed countries by 2050. It is therefore necessary to develop new, faster and more accessible diagnostic tools to limit the large distribution of antibiotics leading to this phenomenon of antibioresistance. We also propose in the last part of this manuscript solutions to integrate our trapping device in order to pave the way for new applications in pathogenic environments
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Strandman, Michelle. "Game mode: on : En kvalitativ studie om den nya idrottsprofilen e-sport i gymnasieskolan." Thesis, Linnéuniversitetet, Institutionen för idrottsvetenskap (ID), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-95813.
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Datorspel och Tv-spel är populärare än någonsin i världen, både i hemmen och på digitala arenor. Eftersom datorspel speciellt blivit en egen sport, e-sport, har det också startats upp e-sportsprogram på gymnasieskolor runt om i Sverige. Syftet är därför att undersöka hur undervisningen ser ut i e-sport och om det kan mäta sig med de traditionella sporterna. Det är även av intresse hur de kopplar e-sportsundervisningen till styrdokumenten. Detta program går under idrott och hälsa specialisering eller träningslära. Metoden för studien var kvalitativ, där semistrukturerade intervjuer användes för att samla in data. Resultatet visade att e-sport inte kunde räknas som en idrott, men att det kunde räknas som en sport precis som andra traditionella sporter enligt intervjuade e-sportslärare. Dock menar de att det är en kognitiv sport och inte en fysisk sport. Inom undervisningen använde sig e-sportslärarna av individuella uppgifter för att möta varje elev. Fokus i uppgifterna var olika strategier utifrån om de var på attack eller försvarssidan. Eleverna skapade även individuella träningsprogram kopplat till e-sport där de satte upp fysiska mål för att kunna hålla sin koncentration uppe längre i sitt spelade samt orka med flera långa matcher.
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Nichols, Karen D. "The diagnostic usefulness of the Wepman Auditory Discrimination Test and the Goldman-Fristoe-Woodcock Test of Auditory Discrimination convergent/discriminant validation /." Theological Research Exchange Network (TREN), 1985. http://www.tren.com.
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Peltier, Marie-Agnès. "Un système adaptatif de diagnostic d'évolution basé sur la reconnaissance des formes floues : application au diagnostic du comportement d'un conducteur automobile." Compiègne, 1993. http://www.theses.fr/1993COMPD634.
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L'objet de la thèse est le développement d'un algorithme de détection d'évolution des caractéristiques d'un système dynamique sur lequel on ne dispose d'aucune connaissance a priori. Le diagnostic d'évolution doit s'adapter à la spécificité du système et à son environnement. Pour cela, on considère l'état initial du système comme un état de référence, à partir duquel tout écart est interprété comme une évolution vers un état inconnu. Chaque état ainsi détecté fait l'objet d'un apprentissage. Pour mettre en œuvre cette idée, nous proposons dans ce mémoire une méthode adaptative de diagnostic d'évolution basée sur la reconnaissance des formes floues. Elle repose sur une modélisation des états du système à l'aide d'ensembles flous. L'approximation des fonctions d'appartenance associées est réalisée à l'aide de réseaux de neurones à fonction d'activation gaussienne. La constitution des ensembles d'apprentissage des états détectés s'effectue selon des critères combinés de proximité dans l'espace et le temps. La notion de "plus proche voisin dans le temps" est introduite. Cette méthode a été appliquée à la surveillance du comportement du conducteur d'un véhicule automobile. L'instrumentation d'un véhicule expérimental et la définition d'un protocole de mesures ont conduit au recueil, sur route réelle, de données pertinentes pour la description de l'activité de conduite. Ces données ont été utilisees pour valider l'algorithme proposé, d'abord pour la détection d'évolution du comportement de conduite, puis dans le cadre plus spécifique de la détection d'hypovigilance. Les résultats obtenus confirment l'intérêt de la méthode proposée.
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Coyle, Monica Norton. "The New Jersey high school proficiency test in writing: a pragmatic face on an autonomous mode /." Access Digital Full Text version, 1992. http://pocketknowledge.tc.columbia.edu/home.php/bybib/11302136.
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Thesis (Ed.D.) -- Teachers College, Columbia University, 1992.Typescript; issued also on microfilm. Sponsor: Clifford Hill. Dissertation Committee: Lucy Calkins. Includes bibliographical references (leaves 195-201).
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Faingold, Alan Mark. "Association Between Recruiters' Perceptions of Education Delivery Mode and Applicants' Workplace Readiness." ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/7640.
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The academy, its faculty, and recruiters have discordant views about credentialed graduates’ workplace viability. As the powerful gatekeepers between education and the employment market, recruiters’ perceptions of college credentials may dictate applicants’ interview progression. Although nearly 100% of today’s college administrators believe higher education programs prepare students for the workplace, less than 12% of recruiters deem graduates ready to succeed in organizational settings after graduation. The purpose of this study was to investigate differences in recruiters’ perceptions of online and face-to-face higher education credentials as indicators of applicants’ workplace readiness. The theoretical foundation of this study was Spence’s signaling theory grounded on the traditional premise that academic credentials profoundly benefit college graduates. Topics of inquiry were recruiters’ perceptions of college degree importance, the applicability of online and face-to-face higher education credentials, academic rigor, educational quality, credential trustworthiness, and applicants’ workplace and leadership readiness. A non-experimental cross-sectional Higher Education and Workplace Readiness Survey comparative design provided quantitative data from 159 recruiters and was analyzed with U, H, and t tests. Recruiters viewed academic credentials as important to applicants’ workplace readiness, yet perceived that online college degree programs lack academic rigor and educational quality. Online bachelors, masters, and doctorate credentials were viewed as inferior to and less trustworthy than face-to-face credentials. Positive social change can occur when academic and organizational leaders collaborate to build principled degree programs around essential job skills, so graduates and recruiters view all academic credentials as trusted predictors of career readiness that benefit society.
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Du, Plessis J., H. S. Friedrich-Nel, and Tonder S. P. Van. "An investigation towards the need for a postgraduate qualification in the specialisation fields of Diagnostic Radiography at the CUT." Interim : Interdisciplinary Journal: Vol 9, Issue 1: Central University of Technology Free State Bloemfontein, 2010. http://hdl.handle.net/11462/341.
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Published ArticleThe current master's degree qualification in Diagnostic Radiography at the Central University of Technology, Free State (CUT) is research based and does seemingly not address the need for training in the specialisation fields of Diagnostic Radiography sufficiently. To address this problem, a needs assessment was conducted amongst qualified diagnostic radiographers in Bloemfontein and Kimberley by means of quantitative questionnaires, qualitative interviews and a focus group discussion. The main aim of the needs assessment was to determine the need for a postgraduate qualification for radiographers in the specialised fields. The possible structure of such a program and the preferred mode of delivery were also investigated. The results of the study emphasised the need for a structured postgraduate learning programme in the specialisation fields in Diagnostic Radiography in the region. Responding to this validated need for a structured postgraduate qualification at the CUT, the current master's degree was revised to accommodate the results of the study and it was proposed to the Professional Board for Radiography and Clinical Technology for approval.
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Menhour, Lghani. "Synthèse de commandes au volant d'une automobile pour le diagnostic de rupture d'un itinéraire : développement et validation expérimentale." Compiègne, 2010. http://www.theses.fr/2010COMP1915.
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L’objectif de cette thèse, est de développer des lois de commande et un observateur de dévers, pour le diagnostic des situations critiques, cette application est connue sous le nom "diagnostic de rupture d’un itinéraire", elle consiste à identifier la vitesse limite de franchissement d’une infrastructure. Cette vitesse est mise en évidence par un fonctionnement du véhicule dans les zones non-linéaires. L’exploration vers la dynamique limite requière un modèle réaliste d’un véhicule réel. La première phase de ce travail, consiste à concevoir des commandes pour extrapoler le comportement du modèle du véhicule. Plusieurs lois sont proposées et validées, certaine d’entres elles contrôlent le véhicule via l’angle de braquage, d’autres contrôlent le véhicule à la fois via le couple de braquage et le couple de traction à la roue. La deuxième phase est l’estimation du dévers de la chaussée par un observateur à entrée inconnue, ceci dans le but de rendre la trajectoire plus réaliste et de tenir compte des effets de ce dernier sur le comportement dynamique du véhicule. La troisième phase présente l’extrapolation du comportement du véhicule, observé lors d’un passage en sollicitations modérées, vers une perte de contrôle virtuelle, cette extrapolation est réalisée en utilisant plusieurs instances du modèle dynamique exécutées avec des vitesses incrémentées, ces modèles sont pilotés par des lois de commande et couplés à l’observateur du dévers. La dernière phase est consacrée à l’étude et à l’analyse des sorties des modèles extrapolés, en utilisant des critères de détection de la dynamique limite du véhicule. Cette phase permettra la détection des situations dangereuses ou/et l’enrichissement des bases de données routières. Cette étude présente d’importantes phases de validation expérimentale des modèles du véhicule, des lois de commande et de l’observateur en utilisant les données expérimentales du véhicule prototype Peugeot 307 développé par l’INRETS-MA, ainsi que les données expérimentales dévers des véhicules VANI et PALAS2. Ce travail a abouti à la conception des modules (commandes et observateur) opérant en temps réelThe aim of this thesis is to develop control laws and road bank angle estimation, for the diagnosis of critical situations, this application is known as "Itinerary Rupture DIagnosis", which aims to evaluate the physical limits of a vehicle negotiating a bend, these limits are highlighted when the vehicle operating in the non-linear areas. The exploration to the limit dynamic requires a realistic model of a real vehicle. The first step of this work, is to design linear and non linear control laws, to extrapolate the behaviour of the vehicle model. Several control laws are proposed and validated, some of them control the vehicle via the steering angle, further at the same time control the vehicle via the steering torque and the wheel traction torque. The second step is dedicated for the estimation of the road bank angle using an unknown input sliding mode observer, this in order to make the trajectory more realistic and take into account the effects of this angle on the dynamic behaviour of the vehicle. The third step presents the speed extrapolation tests, starting from a normal driving situation, towards a virtual loss of control, this extrapolation is performed using several instances of a dynamic model run with incremented speeds, these models are controlled by control laws and coupled with road bank angle observer. The last step is devoted to the study and analysis of extrapolated output models, using detection criteria on the limit vehicle dynamics. This phase will allow the detection of dangerous situations and/or save them in the accident road databases. This study provides an important experimental validation phases of the vehicle models, control laws and observer. This validation is performed using experimental data acquired by prototype vehicle Peugeot 307 developed by INRETS-MA, and the bank angle experimental data of the two vehicles VANI and PALAS2. This work led to the design of modules (commands and observer) operating in real time
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Leggett, Heather Danielle. "Helping clinical educators provide effective feedback to medical trainees on their diagnostic decision making : an educational design research approach." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/13434/.
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An educational design research approach (EDR) was adopted to understand what type of feedback is most effective to enhance medical trainees’ diagnostic decision making (DDM) in authentic clinical settings and how this understanding can be used to improve the feedback provided by clinical educators. Research was conducted within the three phases of EDR: 1) preliminary, 2) developmental and 3) assessment. Findings from the preliminary research phase indicated that more structured and specific feedback which focused on self-regulated learning (SRL) and contextual factors would be advantageous for medical trainees. A conceptual model of feedback that incorporated these findings was developed to inform a Personalised Model of Feedback (PFM) intervention in the development phase. Despite a positive response to the PFM intervention, recruitment was poor which highlighted barriers to involving clinical educators in research and training. Six clinical educators used the PFM intervention to provide feedback to their medical trainees after DDM in the authentic clinical setting. Using a mixed methods approach, the assessment phase evaluated participants’ perceptions of the PFM intervention. Participants found the PFM intervention useful, usable and effective for providing feedback on DDM. After participation more feedback was provided on SRL, confidence and the influence of contextual factors on DDM. Clinical educators and medical trainees also had an increased awareness of the influence of contextual factors on DDM. Medical trainees viewed SRL focused feedback as effective and useful for improving DDM and used more SRL skills on hypothetical reasoning cases. This research has added to current research on the use of SRL to provide feedback. It is the first research to specifically address how feedback after DDM can be better provided to medical trainees and shows that the PFM feedback can be given as an add on to feedback usually provided. Further research is necessary to modify the conceptual model and the PFM intervention to improve its ease of use in the authentic clinical setting, its receptivity by clinical educators and to determine whether it leads to an improvement in medical trainees’ DDM.
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Adair, Carole. "Parental perceptions of the efficacy of diagnostic and educational pathways for children with autistic spectrum disorder in Northern Ireland." Thesis, University of East London, 2010. http://roar.uel.ac.uk/3139/.
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Services for children with autism in Northern Ireland, over the past decade, have been reviewed and developed. The purpose of this study was to explore parental perceptions of the efficacy of resource allocation within education, and to highlight areas for further improvement. Two groups of parents were surveyed, in 1994 and in 2009. Parental opinions in relation to assessment, diagnosis, education and support services were examined across both years, to evaluate the match between the parental definition of effective service delivery and the aims, intentions and actions of the strategic planners. A mixed method design was used, incorporating descriptive and inferential statistics,content analysis of open-ended responses, and a thematic analysis of final comments. The aim was to identify general trends across the participant parent populations (1994 and 2009), in relation to their perceptions of service delivery, but also to record detailed accounts of parents' personal experiences of the present systems. Findings indicated that although assessment and diagnostic procedures for children with autism appear to have improved, following diagnosis, there was still a distinct lack of support, advice and guidance for parents in relation to educational issues. Parents in both years felt that the Special Educational Needs (SEN) system did not cater specifically for children with autistic spectrum disorder, and that a Statement of SEN was a legal necessity to safeguard educational provision and resources. In both 1994 and 2009 parents suggested that schools needed to equip themselves more thoroughly, through training of teachers, and translation of learned skills into classroom practice, to work with the strengths of the children with autism, rather than the deficits. More attention needed to be given to the development of a social skills curriculum and extra-curricular activities. In addition to highlighting parental opinions on the efficient use of scarce resources, this study adds to growing research, illustrating the importance of developing parent professional partnerships in Northern Ireland.
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Chapman, John Shadrack. "Task-Level Feedback in Interactive Learning Enivonments Using a Rules Based Grading Engine." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6605.
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In order to improve the feedback an intelligent tutoring system provides, the grading engine needs to do more than simply indicate whether a student gives a correct answer or not. Good feedback must provide actionable information with diagnostic value. This means the grading system must be able to determine what knowledge gap or misconception may have caused the student to answer a question incorrectly. This research evaluated the quality of a rules-based grading engine in an automated online homework system by comparing grading engine scores with manually graded scores. The research sought to improve the grading engine by assessing student understanding using knowledge component research. Comparing both the current student scores and the new student scores with the manually graded scores led us to believe the grading engine rules were improved. By better aligning grading engine rules with requisite knowledge components and making revisions to task instructions the quality of the feedback provided would likely be enhanced.
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Wagner-Welsh, Shirley Joy. "The identification of criteria to be utilised in mathematical diagnostic tests." Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/708.
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School-related mistakes and low pass rates have led this researcher to perceive that some students are not adequately prepared for Mathematics 1. To address the problem of under-preparedness overseas universities use placement or diagnostic tests. Diagnostic testing identifies areas of weakness and provides information to guide the development of appropriate remedial support. This researcher embarked on a study to identify the sub-domains (criteria) that should be included in a diagnostic Mathematics test battery at the NMMU. An analysis of first-year curricula was undertaken to determine the required Mathematical pre-knowledge and skills entry-level students should have. Thereafter, the required pre-knowledge and skills were reflected against the standard grade school syllabi. From this it was determined that the school learners should acquire the necessary pre-knowledge and skills for university success as part of the school syllabus. However, in reality this is not the case as the researcher and other Mathematics lecturers identified a number of basic errors that incoming students make. This suggests that they have not developed all the required knowledge and skills. Furthermore, their performance in the matriculation examinations does not provide an adequate measure of the requisite Mathematical pre-knowledge and skills necessary for success at university-level Mathematics. No suitable existing diagnostic Mathematics test could be found. By utilizing both an action research as well as a test development methodology, the researcher thus proceeded to delineate the sub-domains that should be included in a diagnostic Mathematics test battery. Thereafter, test specifications were developed for two pilot tests and items were developed or sourced. The constructed response item-type was chosen for the pilot tests as it was argued that this item-type was more useful to use in a diagnostic test than a multiple-choice item format, for example. The pilot test battery, which consisted of a pilot Arithmetic and Algebra and Calculus tests, was administered to a sample of first-year students at the NMMU in 2004 and their performance in Mathematics at the end of the first year was tracked. Tests were scored holistically and analytically to provide a rich source of information. Thereafter, the test results were analysed to obtain evidence on the content validity of the pilot tests, including the item difficulty values and the item-total correlations; to determine the predictive validity of performance on the pilot tests with respect to final first-year Mathematics marks; and their reliability was determined using the Cronbach’s Alpha statistic. These findings suggest that appropriate sub-domains (criteria) were delineated and the items appropriately covered these sub-domains (i.e. the content validity of the pilot tests is acceptable). Furthermore, the predictive validity of the pilot ix tests was found to be acceptable in that significant correlations were found between the pilot tests and performance in first-year Mathematics. Finally, the pilot tests were found to be reliable. Based on the results, suggestions are made regarding how to refine the diagnostic test battery and the research related to it. The final diagnostic Mathematics test battery holds much potential to be able to assist in the early identification of at-risk students who can be timeously placed in developmentally appropriate Mathematics modules or provided with appropriate remedial intervention.
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Sterling, Tania M. "The Effect of Reading Test Mode Interchangeability and Student Assessment Preferences on Achievement." ScholarWorks, 2011. https://scholarworks.waldenu.edu/dissertations/1025.
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Computer-based testing (CBT) in education is on the rise; however, researchers question the interchangeability of CBT and pencil-based testing (PBT). Educators and leaders need to consider test mode interchangeability and student assessment preference prior to adopting CBT in K-8 schools. Following the new literacies theory, this mixed methods study examined test mode preference, the effect on achievement, and factors that influenced student preferences. Research questions investigated participants' computer attitudes and use to determine test mode preference, the impact of test mode and test mode preference on achievement, and factors that influence testing preferences. This sequential explanatory within-group design included 2 online surveys and 2 reading tests in CBT and PBT formats. Paired-sample t tests were used to analyze reading test data preferred and nonpreferred test modes and across CBT and PBT test modes. Qualitative themes were generated and coded using an inductive approach, and patterns among data were analyzed. Findings revealed that all participants used technology regularly at home and at school, and most students preferred CBT over PBT. Quantitatively, there were no significant differences in reading achievement between students' preferred and nonpreferred test modes or between CBT and PBT test formats. Qualitative analysis indicated that students who chose PBT as their preferred test mode did so due to their familiarity with the format. Overall, results supported the idea that CBT and PBT were interchangeable. Implications for positive social change include increasing teachers' effective use of testing modes to improve student confidence, which may translate into improved student achievement.
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Harper, Lisa M. "African American Male Community College Completion and Mode of Instruction." ScholarWorks, 2015. https://scholarworks.waldenu.edu/dissertations/543.
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Despite innovative policy and pedagogical transformations, postsecondary achievement gaps continue to exist between African American males and other students. Low college credential completion rates by African American males have prevented an East Texas community college from meaningful participation in the President's 2020 postsecondary education attainment goal of increasing U.S. college graduates by 5 million. The purpose of this quantitative study was to investigate a hypothesized connection between the independent variable, mode of instruction, and the dependent variables, mathematics course completion and college completion by African American males. Guided by Ogbu's cultural-ecological theory of minority school performance, a chi-square test of independence was used to compare 407 African American males who participated in the mode of lecture and 412 who participated in modular instruction. Findings included a significant relationship (p <.05) between mode of instruction and developmental mathematics completion (p = .000) with the lecture mode associated with higher achievement. No significant relationship existed between instructional mode and college credential completion (p = .503). These findings called the effectiveness of modular instruction into question and indicated that, at this research site, the instructional mode in developmental mathematics is insufficient to address the disparity in college completion rates of African American males. These results informed a policy recommendation paper, written to help local college administrators better understand African American male remedial math and college credential completion rates. This study contributes to positive social change by generating data-based local institutional policies that will promote African American male postsecondary achievement.
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Maamouri, Rebah. "Diagnostic et commande tolérante aux défauts appliqués à un système de conversion électromécanique à base d’une machine asynchrone triphasée." Thesis, Ecole centrale de Marseille, 2017. http://www.theses.fr/2017ECDM0009/document.
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L’objectif de cette thèse est de proposer des stratégies de diagnostic dans le cas d'une commande en vitesse sans capteur mécanique (vitesse/position) d’une machine asynchrone triphasée en présence de défaut d'ouverture des transistors IGBT (Insulated Gate Bipolar Transistor) de l’onduleur. Une étude de l’impact de ces défauts sur les performances de ces structures sans capteur mécanique en termes de stabilité et de robustesse des observateurs en mode dégradé est présentée. Un observateur par mode glissant (Sliding Mode Observer) à base de modèle est développé et validé expérimentalement en vue de la commande sans capteur mécanique de la machine asynchrone triphasée. Les signaux issus de l’observateur (approche modèle) sont utilisés conjointement avec ceux mesurés (approche signale) pour former une approche hybride de diagnostic de défauts des transistors IGBT de l’onduleur. Un observateur par mode glissant d’ordre 2 à base d’un algorithme Super-Twisting est ensuite développé en vue d’améliorer la stabilité et d’assurer la continuité de fonctionnement du système en présence d'un défaut afin de pouvoir appliquer une stratégie de commande tolérante aux défauts dans les meilleures délais et conditions de fonctionnementThe main goal of this thesis is to propose diagnostic strategies in the case of a sensorless speed control of a three-phase induction motor under an opened-switch or opened-phase fault. A qualitative analysis of the performances, in terms of stability and robustness, of sensorless control applied to the electrical drive in pre-fault and post-fault operation modes is presented. A model-based sliding mode observer is developed and experimentally validated for sensorless speed control of three-phase induction motor. The signals issued from the observer (model approach) as well as the measured ones (signal approach) are simultaneously used to form a hybrid approach for inverter open-switch fault detection and identification. A second-order sliding mode observer based on Super-Twisting algorithm (STA) is also developed to improve the stability and to ensure the continuity of operation of the electrical drive especially during transient states induced by the fault, permitting thus to apply the reconfiguration step without losing the control
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Sellami, Takwa. "Contribution à l’usage de l’analyse vibratoire comme outils de monitoring et de diagnostic d’avaries pour les machines électriques tournantes." Thesis, Cergy-Pontoise, 2017. http://www.theses.fr/2017CERG0915.
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Les capacités installées d’énergie éolienne continuent à croître rapidement et prennent une place de plus en plus significative dans le monde. Au fur et à mesure, les études menées sur la conception, la sureté de fonctionnement et la supervision de la chaîne éolienne ont pris progressivement de l’importance. Deux axes de recherche ont été privilégiés dans cette thèse. Le premier concerne la continuité de service d'une éolienne connectée au réseau en présence de défaut de court-circuit entre spires dans une phase du stator de la génératrice asynchrone à cage d'écureuil. L'analyse du défaut ainsi que son impact sur le système éolien et notamment sur la qualité de la puissance produite souligne l'intérêt de développement d'un algorithme de détection et d'isolation rapide, dédié par la suite à la reconfiguration de la commande. Ainsi, une commande tolérante au défaut (CTD) a été conçue de manière à éviter l'arrêt de la production, compenser l'impact de défaut et garder des performances acceptables de la qualité d'énergie produite. Le travail effectué s'est articulé sur les observateurs à mode glissant (OMG), communément connus comme outil puissant pour la supervision et la commande à la fois. Le deuxième axe porte sur la sécurité structurale et la stabilité du système éolien sous contraintes vibratoires. Les travaux se répartissent en deux parties complémentaires : L'établissement d'un modèle numérique tridimensionnel (3-D) sous un logiciel d’analyse par éléments finis (ANSYS) et la réalisation des essais vibratoires sous différentes excitations au sein d'une plateforme vibratoire (TREVISE). Dans ce cadre, un modèle numérique (3-D) d'une éolienne à axe horizontal couplée à un mât et une fondation adéquats a été développé en utilisant la méthode de volumes finis (FVM) afin d'appréhender son comportement vibratoire. Les essais vibratoires expérimentaux valident le modèle numérique et permettent l’identification de la réponse dynamique de la structure d'une manière fine. De plus, nous avons élaboré un modèle expérimental de la tenue de l’éolienne aux contraintes vibratoires de formes aléatoire, sinusoïdale et impulsionnelleThe wind energy capacity carries on growing quickly and taking an increasingly significant place in the world. Progressively, research studies dealing with designing and supervising wind turbines have become more important. Two areas of research were developed in this thesis. The first one concerns the continuity of service of a wind turbine connected to the grid while an inter-turn short-circuit fault is present in the stator phase of the induction squirrel cage generator. The analysis of the fault as well as its impact on the wind turbine system and mainly on the quality of the produced power highlights the interest of development of a fast detection and isolation algorithm, dedicated to the reconfiguration of the control law. Hence, a fault tolerant control scheme has been established in order to avoid stopping production, compensate the fault impact and maintain acceptable performances of the quality of the produced energy. The carried out work was based on sliding mode observers, commonly known as robust tools for monitoring and controlling at the same time. The second axis concerns the structural modeling and stability checking of the wind system under vibratory stresses. The work is divided into two complementary parts: The establishment of a three-dimensional (3-D) numerical model using a finite element analysis software (ANSYS) and the realization of vibratory tests under different excitations within the platform (TREVISE). In this framework, a numerical (3-D) model of a horizontal axis wind turbine coupled to a suitable tower and foundation was developed basing on the finite volume method (FVM) in order to analyze its vibratory behavior. The experimental vibratory tests validate the numerical model and allow the identification of the dynamic response of the structure in a precise way. In addition, we have developed an experimental model of the behavior of the wind turbine under vibratory stresses of random, sinusoidal and impulse shapes