178 research outputs found
Automatic authoring in the LAOS AHS authoring model
No full textIn this paper, we extend the automatic authoring techniques that can be built based on the LAOS model, a five-layer AHS authoring model. As the LAOS model itself is fairly complex, although information-rich, an adaptive hypermedia author needs a lot of system support to be able to populate all its levels with the corresponding information. Therefore, such automatic authoring techniques, which are actually automatic transformation (and interpretation) rules between the different layers of the model, have been designed. These automatic rules represent, in the area of adaptive systems, designer-goal oriented adaptation techniques. They should represent the goal of the designer that is authoring the hypermedia (such as the pedagogical goal in educational adaptive hypermedia). Therefore, this paper represents yet another step towards an adaptive hypermedia (or adaptive course) that ‘writes itself’. The focus here is on automatic transformation between the domain and a newly introduced goal and constraints model, to show that the effort of introducing this new layer can be minimal
Comparative analysis of adaptation in adaptive educational hypermedia and IMS-learning design
No full textCurrently, Adaptive Educational Hypermedia (AEH) and IMS Learning Design (IMS-LD) are separate research areas, with little shared knowledge between them. Their goal, however, is the same: to design, author and implement the best possible learning experience for the learner. This paper addresses the issue of differences and similarities between AEH and IMS-LD with regard to knowledge representation and adaptation and investigates, generically, as well as for the specific case of the Layered AHS Authoring-Model and Operators (LAOS) framework, how these paradigms can benefit from each other
A quasi-Linear Parameter Varying (qLPV) Approach for Tiltrotor Conversion Modeling and Control Synthesis
No full textA safe conversion of tiltrotor from helicopter mode to airplane mode is ensured through maneuvering within the conversion corridor, a constrained region in the airspeed versus nacelle angle graph. This paper presents preliminary work in the development of an automatic conversion maneuver. A high order quasi-Linear Parameter Varying model is developed for XV-15 that combines discrete state-space models to provide a varying model dynamics and trim characteristics during the conversion maneuver. Tracking control system based on gain scheduled linear quadratic tracker with integrator (LQTI) is designed for automatic conversion maneuver for XV-15 based on the qLPV model. Lastly, an optimization routine is performed to fly various conversion trajectories and identify optimal conversion maneuver
Design of the CAM model and authoring tool
No full textStudents benefit from personalised attention; however, often teachers are unable to provide this. An Adaptive Hypermedia (AH) system can offer a richer learning experience in an educational environment, by giving personalised attention to students. On-line courses are becoming increasingly popular by means of Learning Management Systems (LSM). The aim of the GRAPPLE project is to integrate an AH with major LMS, to provide an environment that delivers personalised courses in a LMS interface. However, designing an AH is a much more complex and time-consuming task, than creating a course in a LMS. Several models and systems were developed previously, but the (re)-usability by educational authors of the adaptation remains limited. To simplify adaptive behaviour authoring for an educational author, a visual environment was selected as being most intuitive. This paper describes a reference model for authoring in a visual way and introduces an authoring tool based upon this model
Das Österreichbild von AHS-Schüler/innen der Sekundarstufe II
No full textDiese Diplomarbeit ist im Zuge des Forschungsprojekts „Das Österreichbild in den audiovisuellen Medien für den Unterricht in Geschichte, Sozialkunde und Politischer Bildung und seine Repräsentanz bei ausgewählten Schüler/innen-Kohorten der AHS (ÖNB Jubiläumsfonds, 2015-2017)“ entstanden. Ihr Ziel ist es, erstens zu untersuchen, worin das Österreichbild von Schüler/innen der AHS, Sekundarstufe II, besteht und zweitens, wie Zeitgeschichte in ihrem Geschichtsbewusstsein verankert ist. Zur Beantwortung der Fragestellungen wurden Schüler/innen ausgewählter Schulen im Zuge dreier Fragebögen sowohl zu ihrem Geschichtsbewusstsein als auch zu Assoziationen mit österreichischer Geschichte ab 1945 befragt. Die dabei erhobenen Daten wurden in Anlehnung an Philipp Mayrings zusammenfassende qualitative Inhaltsanalyse ausgewertet.
Die Auswertung der Befragung zeigt, dass regionale Vorstellungen vordergründig ländlich mit Fokus auf Gebirgsregionen geprägt sind. Allerdings fungiert auch der städtische Bereich als Identifikationsträger, wobei hier Wien, gefolgt von Salzburg deutlich dominiert. Mit typischen Österreicher/innen werden, unabhängig von Geschlecht und Migrationshintergrund der Befragten, vor allem Männer assoziiert, die numerisch überlegen und hinsichtlich ihrer Qualitäten deutlich heterogener als Frauen angegeben wurden. Frauen werden vornehmlich mit Sport, respektive Skisport in Verbindung gebracht. Für einen Großteil der Befragten stellt Abgeschlossenheit kein obligatorisches Kriterium von Zeitgeschichte dar, deren Beginn vornehmlich noch vor dem Zweiten Weltkrieg verortet wird.
Abschließend werden die Ergebnisse der Untersuchung in den Kontext des AHS-Lehrplans für „Geschichte, Sozialkunde und Politische Bildung“ gestellt, wobei die Notwendigkeit einer stärkeren Fokussierung auf die Behandlung von Frauen- und Geschlechtergeschichte argumentiert wird.This diploma thesis was written in association with the research project “Das Österreichbild in den audiovisuellen Medien für den Unterricht in Geschichte, Sozialkunde und Politischer Bildung und seine Repräsentanz bei ausgewählten Schüler/innen-Kohorten der AHS (ÖNB Jubiläumsfonds, 2015-2017)“. The author‘s main goals are to inquire the characteristics of conceptions of Austria by students in secondary school (Allgemein bildende höhere Schule/age 15-16) and how contemporary history is represented in their historical awareness. In order to answer these questions students from selected schools were asked to fill in three separate questionnaires about their historical awareness and their associations with Austrian history starting 1945. The acquired data was analyzed following Philipp Mayring‘s Qualitative Content Analysis.
The evaluated data indicates that regional conceptions are characterized above all rural focussing mountainous regions. However, urban regions act as identificiation carriers as well, with Vienna taking the dominating position, followed by Salzburg. Typical Austrians are, unaffected by gender and migratory background of the stu-dents, predominantly seen as males. They are mentioned more often than females and characterized more heterogeneously. Women are above all associated with sports respectively ski sports. Most of the respondents don’t see beeing completed as an obligatory criterion of contemporary history, while its beginnings are located predominantly before World War II.
In conclusion, the results of the study are put into context of the curriculum of “Ges-chichte, Sozialkunde und Politische Bildung“ (Allgemein bildende höhere Schule/ secondary school). The author argues the necessity of intensifying lessons in Wom-en’s History and Gender History in the classroom
An examination of organochlorine insecticide exposures and associated cancer risks among the agricultural health study (AHS) farm spouses
No full textIntroduction: Organochlorine insecticides (OCs) are a class of pesticides historically used to control for insects in agriculture worldwide and that are still used in developing countries today for the control of vector borne illnesses. OCs were mostly banned in the United States in the 1970s and 1980s, with lindane and endosulfan having only been banned recently in 2006 and 2010, respectively. The strongest epidemiologic evidence for OC insecticide exposures and cancers comes from occupational and population-based studies of lymphohematopoietic cancers, specifically non-Hodgkin lymphoma (NHL). Many population-based studies evaluating OCs have focused on breast cancer, but the majority of these results have been inconsistent. While most epidemiologic studies of OCs have included male pesticide applicators, few analyses have included female spouses of pesticide applicators, warranting further research to examine the impact of OC exposures on the risk of female-specific cancers. Female spouses of pesticide applicators may be exposed to OC insecticides from their personal use (i.e., mixing/applying of pesticides), and indirect exposure from non-occupational expo¬¬¬sure pathways (i.e., agricultural drift, take-home and residential use). The following projects will explore the impact of both personal use and non-occupational exposures to seven OCs (i.e., aldrin, chlordane, dieldrin, DDT, heptachlor, lindane and toxaphene), with risk of cancer among the Agricultural Health Study (AHS) farm spouses (n=32,345).
Methods: My first aim is to conduct an epidemiologic analyses to examine associations between the AHS farm spouses’ personal use of each of seven OCs with total and specific cancers. My second aim is to characterize the AHS farm spouses’ non-occupational OC exposures to each of the seven OCs by applying an active ingredient-specific exposure algorithm recently developed by AHS researchers. My third aim is to conduct a second epidemiologic analysis examining the associations between the AHS farm spouses’ non-occupational exposures on their risk of developing breast cancer. Together, these aims will elucidate the impact of exposures to seven individual OCs, through personal use and multiple non-occupational exposure pathways, on the risk of cancer among the AHS farm spouses.
Results: In the first aim, most cancers were not associated with OC use. Risk of glioma was increased among users of at least one OC and specifically among lindane users. Multiple myeloma was also associated with chlordane. There were also positive associations between pancreatic cancer and lindane, and ER-PR- breast cancer and dieldrin. The second aim identified an additional 1.2-10.0% of female farm spouses exposed to individual OCs through individual non-occupational pathways. In addition, I captured variability in OC exposure intensities among the AHS spouses, with ratios of the 75th to 25th percentiles ranging from 2.8 to 8.5. The agricultural drift and take-home pathway estimates were highly correlated with each other across all OCs (rs ≥ 0.98). The residential use pathway was not correlated with either the agricultural drift nor take-home pathways for chlordane or heptachlor (rs < 0.02), which were the only OCs with residential use. In the third aim, most individual exposure pathways of individual OCs were not associated with breast cancer overall or with ER+PR+ breast cancer. Toxaphene exposure through the take-home pathway was associated with ER+PR+ breast cancer. Aldrin and toxaphene exposures through the agricultural drift pathway were associated with overall and ER+PR+ breast cancers. Chlordane and heptachlor exposures through the residential use pathway were associated with ER+PR+ breast cancer. Finally, overall non-occupational exposures of aldrin, heptachlor and toxaphene were associated with ER+PR+ breast cancer.
Discussion: This dissertation has demonstrated that exposures to OCs through their personal use and through non-occupational pathways may contribute to an increased cancer risk among female farm spouses of pesticide applicators. Prior to this study, few analyses have examined OC insecticide use and cancer risk among female spouses of pesticide applicators. In addition, studies which have evaluated cancer associations with non-occupational pesticide exposures have been limited by surrogate measurements, unavailable questionnaire information, and non-specific biological markers. Furthermore, the studies presented herein may help to inform future risk analyses of OC exposures and cancer outcomes, as well as future exposure assessments of non-occupational OC exposures among farm women.Ph.D.Includes bibliographical reference
Automatic Authoring in the LAOS AHS Authoring Model Abstract
No full textIn this paper, we extend the automatic authoring techniques that can be built based on the LAOS model, a five-layer AHS authoring model. As the LAOS model itself is fairly complex, although information-rich, an adaptive hypermedia author needs a lot of system support to be able to populate all its levels with the corresponding information. Therefore, such automatic authoring techniques, which are actually automatic transformation (and interpretation) rules between the different layers of the model, have been designed. These automatic rules represent, in the area of adaptive systems, designer-goal oriented adaptation techniques. They should represent the goal of the designer that is authoring the hypermedia (such as the pedagogical goal in educational adaptive hypermedia). Therefore, this paper represents yet another step towards an adaptive hypermedia (or adaptive course) that ‘writes itself’. The focus here is on automatic transformation between the domain and a newly introduced goal and constraints model, to show that the effort of introducing this new layer can be minimal
Diagnostic accuracy of a duplex real-time reverse transcription quantitative PCR assay for detection of African horse sickness virus.
No full textBlood samples collected from 503 suspect cases of African horse sickness (AHS) and another 503 from uninfected, unvaccinated South African horses, as well as 98 samples from horses from an AHS free country, were tested with an AHS virus (AHSV) specific duplex real-time reverse transcription quantitative PCR (RT-qPCR) assay and virus isolation (VI). The diagnostic sensitivity and specificity of this AHSV RT-qPCR assay and VI were estimated using a 2-test 2-population Bayesian latent class model which made no assumptions about the true infection status of the tested animals and allowed for the possibility of conditional dependence (correlation) in test results. Median diagnostic sensitivity and specificity of the AHSV RT-qPCR were 97.8% and 99.9%, respectively. Median diagnostic specificity of virus isolation was >99% whereas the estimated diagnostic sensitivity was 44.2%. The AHSV RT-qPCR assay provides for rapid, high-throughput analysis of samples, and is both analytically and diagnostically sensitive and specific. This assay is potentially highly useful for demonstrating freedom or infection of horses with AHSV, thus it is appropriate that its reproducibility be evaluated in other laboratories as a global standard for detection of AHSV
Automatic authoring in the LAOS AHS authoring model
No full textIn this paper, we extend the automatic authoring techniques that can be built based on the LAOS model, a five-layer AHS authoring model. As the LAOS model itself is fairly complex, although information-rich, an adaptive hypermedia author needs a lot of system support to be able to populate all its levels with the corresponding information. Therefore, such automatic authoring techniques, which are actually automatic transformation (and interpretation) rules between the different layers of the model, have been designed. These automatic rules represent, in the area of adaptive systems, designer-goal oriented adaptation techniques. They should represent the goal of the designer that is authoring the hypermedia (such as the pedagogical goal in educational adaptive hypermedia). Therefore, this paper represents yet another step towards an adaptive hypermedia (or adaptive course) that ‘writes itself’. The focus here is on automatic transformation between the domain and a newly introduced goal and constraints model, to show that the effort of introducing this new layer can be minimal
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