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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
481

Students' conceptions of solubility : a teacher-researcher collaborative study

Ebenezer, Jazlin Vasanthakumari January 1991 (has links)
For the last fifteen years, research on students' conceptions of physical phenomena has been directing our attention to the value of knowing and considering children's prior ideas in science teaching. Although many who are concerned with science education are aware of and see wisdom in this perspective of teaching, there are many realities, including the content of the discipline, that pose great challenges in translating it into practice in science classes. Currently, in collaboration with teachers, science educators are actively conducting classroom studies. In this process, teachers as researchers are making reflective inquiries into their own students' learning. This study followed a similar framework of research at a microcosmic level. It entailed elicitation of thirteen Grade 11 students' individual prior conceptions of solubility and a teacher-researcher collaboration to incorporate these conceptions in the instruction of a unit on solution chemistry. Consequently, the study presents a phenomenography of solubility, narrates a story about classroom instruction which took students' conceptions into consideration, reports four case studies on students' conceptual growth and changes, and outlines some of the factors that facilitate or constrain collaborative teaching that focuses on student understanding of subject matter. The students' prior conceptions of solubility were categorized into six categories of description: 1. physical transformation from solid to liquid 2. chemical transformation of solute 3. density of solute 4. amount of space available in solution 5. properties of solute 6. size of solute particles With regard to learning chemistry, these conceptualizations made clear four issues: (1) students' explanations were bounded by their perceptions, (2) students extended macroscopic explanations to a microscopic level, (3) students made inappropriate links to previous chemistry learning, and (4) students used the language of chemistry non-discriminately. After studying a unit on solution chemistry, two more categories of description were added to the pre-instructional categories: 1. chemical structure of components 2. solution equilibrium After instruction, the students attributing to the initial six categories of description' diminished in number. The newly acquired conceptions of solubility reflected insufficient explanatory power and were merely overlaid with the chemical language. Learning the language of solution chemistry and acquiring some theoretical understanding of it were reflected in the change between pre- and post-instructional conceptions. This conceptual change can be considered as evolutionary. It was inferred that the abstract and ambiguous nature of chemical theories and principles sets limits to conceptual change teaching. The influences that facilitated the collaborative efforts include: (1) the teacher's attempts to incorporate students' conceptions, (2) the teacher's openness and willingness to assess her own methods of teaching chemistry, (3) the teacher's reflections about the researcher's constructivist teaching, and (4) the researcher's active participation in the classroom interactions. The four most important influences that seriously constrained the collaborative efforts to link students' conceptions with formal chemistry were: (1) the lack of time to devote to the topic of solution chemistry, (2) the lack of teacher time to plan lessons together in order to incorporate students' conceptions, (3) the lack of practical experience on the part of both the researcher and the teacher in developing specific teaching strategies which acknowledged students' prior belief in this content area, and (4) the lack of time to develop common perspectives and a shared language. This study has implications for both teachers and researchers. Specifically, it implies that students' conceptions form an integral component of chemistry instruction—as points of origin for lesson planning and development of curricular materials It also implies that through science educators' modelling and practising in their "teaching and learning" courses, pre- and in-service teachers be challenged to seek answers for epistemological questions such as: What is chemical knowledge? and, How is it acquired? A general implication is that both teachers and researchers, rather than being fence-makers, must strive to be bridge-builders so that they can be learners of each other's theoretical and practical experiences. / Education, Faculty of / Curriculum and Pedagogy (EDCP), Department of / Graduate
482

Natural concepts in the domestic dog.

Feuerbacher, Erica Nan 12 1900 (has links)
The current study investigated concept formation in domestic dogs, specifically that of a toy concept. The dog's differential responding (retrieval vs. non-retrieval) to two sets of stimuli suggested a toy concept. Differential responding occurred from the very first trial, indicating that the concept had been formed in the natural environment, not during the experiment. It was hypothesized that a common response may be responsible for the emergence of the class in the natural environment. The results demonstrated that it was possible to expand the class by adding previously non-retrieved objects to the toy class through a common response. It was also shown that the toy concept passed the more stringent criterion (transfer of function test) required validating it as a concept.
483

Conceptual Design of a Polymer Based Joint between Tether and Foundation in Tidal Energy Power Plant : Concept generation and development of a polymer based joint / Konceptuell design av polymerbaserad joint mellan tether och fundament i tidvattenkraftverk : Konceptgenerering och utveckling av polymerbaserad joint

Elisson, Jonas January 2020 (has links)
This master thesis treats the development of a new component in a tidal energy power plant. The technology that the component should be used in extracts energy from tidal an low velocity currents. This is done by that a turbine is placed on a kite which is pushed forward in the water due to the lifting force acting on the wing. A tether connects the kite with a bottom joint that is placed on a foundation at the seabed. The bottom joint used today is heavy and expensive, which was the main reason to that this thesis was initiated. In this work, the possibility of using a polymer based design for the connection between the tether and foundation was investigated. The optimal outcome of the project was that the polymer solution should provide a spring function to the power plant. A lot of conventional product development methods have been used in the project. The project was divided into five parts: planning, product specification, concept generation, concept choice and conceptual design. In order to understand what was required of the solution in terms of the spring function, a model that aimed to represent what effect a spring function would have on the power plant was developed. According to the model, a spring function in the tether direction could increase the velocity of the kite in its trajectory. The model is based on some simplifications which is assessed to need further investigation. The spring function was translated to that the component should be able to elongate as a response to the force acting in the tether direction. In the concept choice phase it was chosen to proceed with a design similar to that of a bend stiffener. It was decided that a spring function was not required of the component, though desirable. A material selection was performed and the most optimal material for a single part that should be able withstand the tension, allow rotation, and provide a spring function was concluded to be TPU(ester, aromatic, Shore 50D). In the attempt to understand what was needed to be considered if the spring function should be solved by a material response in a polymer component, relevant theory was collected. A numerical analysis in Abaqus was performed which indicated that such a solution was unreasonable. It was then decided to proceed with the development of a bend stiffener, where the tether should be connected directly to the foundation. The thesis finally concludes with a conceptual design of a bend stiffener. The most suitable material for a bend stiffener was concluded to be TPU(ether, aliphatic, Shore 60D). The initial dimensions were determined by the maximum angle and tension combination that the tether would be exposed to. A static analysis was performed in Abaqus to illustrate the function of the product. The analysis indicated that a bend stiffener could provide the required function. However, the stress in the component became high, which indicated that the bend stiffener material might fail due to the applied load. In order to fully evaluate this, it was concluded that a more accurate material model was required.
484

Knowledge in Accounting: Using a threshold concept lens to identify knowledge of financial instruments in an Accounting course, as experienced by students at a South African university

Bardien, Mariam 09 September 2020 (has links)
This qualitative research aims to identify the threshold concepts in financial instruments using Meyer and Land's Threshold Concept Framework (2005) and applies the dimension of Semantics and Legitimation Code Theory (Maton, 2014) to analyse whether semantic gravity and semantic density are stronger or weaker in the threshold concepts. The analysis points to five threshold concepts in the financial instruments module. It further aims to explore whether African, Coloured and Indian students' exposure to these threshold concepts results in troublesome knowledge and/or transformation in understanding and thinking in a second-year Accounting course at a South African university. Triangulation is used to confirm the authenticity and consistency of the data emerging from the identification of the threshold concepts. Using Semantics, this research illustrates that the five threshold concepts possess weaker semantic gravity due to the abstract nature of the threshold concepts and stronger semantic density is present due to the complex and dense terminology inherent in financial instruments. Evidence from a general survey, interviews and summative assessments conducted with students registered for an Accounting course shows that exposure to the threshold concepts resulted in troublesome knowledge and/or transformed understanding. Identifying the threshold concepts could make specialised Accounting knowledge more explicit to students and exploring the knowledge experienced as troublesome and the transformed understanding experienced provides room for debate around pedagogy and curriculum reform.
485

Simulační verifikace komplexního technologického projektu / Simulated Verification of Complex Technology Project

Varjan, Matúš January 2016 (has links)
In the introduction, doctoral thesis as a complex technological project uses the summary title Stability of production. Stability of production is defined as a maintaining the required properties of the system over a given time period. Stability of production, based on the literature study included: – generally known systems and concepts, for example Process Stability, System Stability, Toyota Production System, Lean Manufacturing, etc. – less-known systems and concepts, for example Maintaining the fidelity of the production program, Stable order-sequence concept. The practical part of the doctoral thesis is focused on the less-known concept: Stable order-sequence. The task of the Stable order-sequence is to follow the sequence of orders given by the planned production program in the course of the production and at the end of production. Maintaining the sequence of the orders has a positive experience in the logistics activities between the final producer and its suppliers. As it was found by the planned experiment for a full factory plan, the sequence of orders in the material flow of original equipment manufacturer is influenced mainly by: – the cause of the removing orders from material flow, – the effect of the causes LIFO stack vs. branched material flow, – the effect of the causes LIFO stack vs. branched material flow vs. the removing from the material flow. By the analysis of Stable order-sequence, it was found that the methodology of the concept contains deficiencies. It does not state how to choose for example the size of the time period, time interval, data editing etc. By this lack, the subject can skew the results in the evaluation of the indicator PFT0 up to 4 %. Or by using of suitable adjustment, the value of the indicator PFT0 can be improved more than 50 %. To test the concept of a Stable order-sequence in practice has been designed technological project with the support of discrete-event simulation. It was about the implementation of new management logic to the stack behind the welding of original equipment manufacturer. The new logic of management was designed with an emphasis on Stable order-sequence concept, to arrange the orders in process according to the planned sequence. On the base of the functionality verification of the new stack logic, it was found that the logic affects the sequence of the orders, but not fundamentally. In tracking the hourly intervals for 25th calendar week 2013, the value of PFT0 was not improved in 37 cases, the value remains in 30 cases and the value was improved by the value of the median 18,68 % in 30 cases orders.
486

The design of a model for the acquisition, reuse and creation of knowledge in a civil engineering environment

Verbeek, Thomas January 2018 (has links)
A model is designed for the restructuring of knowledge. By way of suitably designed ontologies knowledge can be analysed to facilitate the creation of new knowledge and to render the knowledge suitable for reuse and for linkage to word-wide ontologies. / SUMMARY The need for this research emanated from the requirement for learning and adaptation in the fast-changing world we live in today. The changing world goes along with developments in communication means, whereby information becomes more accessible and sophisticated daily. A vast number of resources is available and accessible, distributing an enormous amount of information. The need is to turn these vast amounts of information into usable knowledge for use by an engineer in practice. Restructuring of knowledge is one way of approaching this need and is addressed in this study. This process can be facilitated by experienced persons who know what knowledge is needed in practice. There is a decline in the numbers of experienced civil engineers, leaving a gap between the supply and demand for suitably qualified and experienced civil engineers. The objective of this study is to meet the need for the restructuring of knowledge by the design a model (referred to as a logic base in this study) for the acquisition, reuse and the creation of engineering knowledge in a civil engineering environment. The main research question posed in this study is as follows: What are the key characteristics of a model (termed a “logic base” in this study) for the acquisition, reuse and the creation of knowledge in a civil engineering environment? This research commences with a set of research questions, followed by a literature review. Consideration is given to theories of knowledge, various methods of knowledge creation and knowledge acquisition. Several problem-solving techniques are reviewed. The structuring and architecture of knowledge and ontologies are researched and the role of systems engineering is studied. Various research methods are investigated and it is shown that case study research is the most suitable for the development of ontologies in civil engineering. The ontology of the logic base is therefore based on typical topics of case studies. Concept maps are employed to structure knowledge. This is done by defining appropriate concepts and classifying these into several ontological levels. The relationships among concepts and other influencing domains are studied. Knowledge of these relationships enables the application of several problem-solving techniques that enhance and stimulate the creation of knowledge. A logic base is designed containing three modules, namely an input module whereby concept maps are used to capture and structure knowledge entities. The second module consists of an analysis module where problem-solving can be done. The third module contains the output of work and processes where engineering knowledge can be documented for reuse. The contribution of this research lies in the design of an application in knowledge management in the field of civil engineering. Integration is done of ontologies, knowledge theories, knowledge acquisition and knowledge creation through problem-solving techniques. Knowledge is structured that can be linked to other external civil engineering taxonomies and ontologies. This enhancement of knowledge makes knowledge explicit and renders it suitable for reuse. When engineers are equipped in the use of the logic base, problems can be addressed in a holistic way and the underlying thought processes can be documented. This may be of great value to inexperienced engineers and for the preservation of valuable knowledge. Some case studies are analysed to demonstrate the functioning of the model. / Thesis (DPhil) University of Pretoria 2018. / Information Science / DPhil / Unrestricted
487

Le passage du lexique courant à la terminologie de la macroéconomie : faits sémantiques et conceptuels : (étude trilingue arabe - français - anglais) / The passage from the current lexicon to the terminology of macroeconomics : semantic and conceptual facts : (Trilingual studyArabic - French - English)

Abualasal, Jaber 03 February 2017 (has links)
Dans cette étude trilingue, nous abordons le passage d’un signe linguistique du lexique courant à la terminologie de la macroéconomie. En effet, la sémantique d’un signe linguistique dans le lexique courant et dans la terminologie semble, de prime abord, identique. Cependant, à l'analyse, des différences sémantiques commencent à émerger. Nous proposons des méthodes d’analyse pour relever les traits sémantiques différents d’un signe linguistique quand il passe du lexique courant à la terminologie de la macroéconomie. D'ailleurs, nous avons porté notre attention sur les termes composés de deux éléments. Le traitement commence par l’élément de base selon des catégories et sous-catégories basées sur les traits sémantiques généraux ou sur le domaine d’origine de l’élément de base. De plus, nous divisons les termes composés en fonction de la structure syntaxique. Ainsi, un chapitre est consacré au traitement des termes composés d’un nom et d'un adjectif, et un autre au traitement des termes composés de deux noms. La structure différente des termes composés nous incite à aborder les types de composés différemment. Pour explique cela, nous remarquons que l'élément de base, dans le composé N1-A1, tende à s'associer avec un adjectif de manière préférentielle ou obligatoire. Ainsi, nous adaptons le concept de la « polarisation » pour traiter le comportement du composé N1-A1 où l'élément de base polarise les adjectifs associés. Par contre, le composé N1-N2 subit une sorte de dilution où l'élément de base peut être remplacé par un synonyme sans changer le concept. D'ailleurs, le composé N1-N2 peut changer de structure sans changer le concept. par conséquent, nous employons le terme « dilution » pour décrire ce comportement.D’un autre côté, nous proposons quelques analyses pour comprendre la sémantique de l’état d’annexion en ce qui concerne les termes composés en arabe N1-N2. Pour ce faire, nous remplaçons l’état d’annexion par des tournures prépositionnelles pour expliciter la sémantique de l’état d’annexion. Cela permet aussi d'établir une catégorisation sémantique de l’état d’annexion. / In this trilingual study, we discuss the passage of a linguistic sign from the current lexicon to the terminology of macroeconomics. Indeed, the semantics of a linguistic sign in the current lexicon and in terminology seem, at first sight, identical. Nevertheless, it is only a detailed analysis, semantic differences begin to emerge. We propose methods in order to analyze the different semantic features of a linguistic sign as it passes from the current lexicon to the terminology of macroeconomics.As for compound terms, we only deal with terms composed of two elements. The treatment begins with the base element according to categories and subcategories based on the general semantic features or on the origin of the base element. In addition, we divide the compound terms by using models based on the syntactic structure. Thus, a chapter is devoted to the treatment of compound terms composed of a noun and an adjective and another is dedicated to the treatment of compound terms composed of tow nouns. The different structure of compound terms encourages us to approach them differently. To explain this, we note that the base element, in compound N1-A1, tends to associate with an adjective in a preferential or obligatory way. Thus, we use the concept of "polarization" to deal with the behavior of compound terms N1-A1 where the base element polarizes the associated adjectives. On the other hand, the compound terms N1-N2 undergoes a kind of dilution where the basic element can be replaced by a synonym without changing concept. Moreover, the compound N1-N2 can change its structure without changing its concept. So we use the term "dilution" to describe this behavior.On the other hand, we offer some analysis to understand the semantics of the genitive case regarding the compound terms in Arabic N1-N2. To do this, we replace the genitive case by prepositional phrases to clarify the semantics of the structure of annexation. This also allows making a semantic categorization for the genitive case.
488

A qualitative investigation into the relationship between self-concept and the propensity for role uptake in a small group

Du Plessis, Melissa 06 December 2011 (has links)
When regarding the history of role theory, one becomes aware of the fact that, although much knowledge is available specifically pertaining to roles in small group settings (e.g. expectations about behaviour, types of roles, flexibility of locus, appropriateness of the role system, dynamic nature of role formation and development as well as typologies dividing roles into categories), not much literature is available specifically pertaining to what the impact of an individual’s self-concept is on his/her propensity to either assume or avoid certain roles in such a setting. Accordingly, this study aimed to explore the above-mentioned aspect of role division in small groups. Research was done by means of a case study research design, with a constructivist/interpretevist meta-theoretical paradigm as research approach. This paradigm holds that there are multiple subjective realities involved when studying human interactions and the consequences thereof. The study was furthermore conducted from a psychodynamic and systems theory perspective. Data was collected from a sample of postgraduate students, who participated in a training group as part of their Industrial and Organisational Psychology master’s degree programme at the University of Pretoria, by means of three different methods, namely video and voice recordings, a document study, as well as semi-structured interviews. Data was furthermore analysed by Atlas.ti, a qualitative data analysis programme, according to the principles of constructivist grounded theory. When regarding current literature on the subject, it is implied by some that an individual will only allow roles to be imposed on him/her if he/she is predisposed to assuming such roles, and if he/she can accordingly integrate the responsibility somehow with his/her self-concept. Accordingly, the results obtained showed some connection between an individual’s self-concept and the role(s) that was assumed by the individual in the small group setting. More specifically, the results showed that an individual is more likely to change roles with ease should the alternate role requirements also be in line with elements of the individual’s self-concept. The results further indicated that it might be difficult for an individual to adapt and change to another role should the roles, which are required in the small group setting, be in conflict with the individual’s self-concept. These findings thus imply that an individual’s self-concept might have an impact on an individual’s propensity to either assume or avoid certain roles (role valency) in a small group setting. / Dissertation (MCom)--University of Pretoria, 2011. / Human Resource Management / unrestricted
489

Feedback zu Concept Maps im betriebswirtschaftlichen Planspielunterricht - eine empirische Untersuchung

Ryssel, Jeannine 21 May 2019 (has links)
Um Lernende schon frühzeitig auf die komplexen Problemsituationen der Arbeitswelt vorzubereiten, muss die Ausbildung zukunftsfähig gestaltet werden. Dafür ist ein aktiver und selbstgesteuerter Umgang mit komplexen Sachverhalten erforderlich. Vor diesem Hintergrund werden verstärkt Komplexe Lehr-Lern-Arrangements, z. B. Planspiele, eingesetzt. Lernende werden auf diese Weise spielerisch mit authentischen realitätsnahen Situationen konfrontiert. Hierbei gilt es zu beachten, dass Planspiele selbst bei einer angemessenen Konstruktion nicht automatisch lernwirksam sind. Umfangreiche Forschung hat gezeigt, dass Planspiele keine Selbstläufer sind und es einer instruktionalen Unterstützung, z. B. durch den Einsatz von Lernstrategien, bedarf. Eine mögliche Lernstrategie stellt dabei die Anwendung von Concept Maps dar, da gerade diese Lernstrategie das Verständnis von Zusammenhängen besonders gut fördern kann. Dabei hat die Forschung zu Concept Mapping gezeigt, dass insbesondere fachlich und methodisch unerfahrene Lernende instruktional unterstützt werden müssen. Eine Möglichkeit ist dabei, den Lernenden Feedback zu ihren erstellten Concept Maps zu geben, um ihre kognitive Belastung zu reduzieren. Für die Untersuchung wurden die beiden Forschungsstränge zum Concept Mapping und zum Feedback miteinander verbunden. Ziel der Untersuchung war es herauszufinden, inwieweit Feedback zu Concept Maps tatsächlich zu einer Verbesserung der Lernleistung führt und welches Feedback dabei ggf. lernwirksamer ist. Des Weiteren stellte sich die Frage, inwieweit die Lernwirksamkeit eines ergänzenden Feedbacks bzw. die Art des Feedbacks von personalen oder situativen Einflussfaktoren abhängt. Vor diesem Hintergrund wurden drei Forschungsfragen bearbeitet: 1) Inwieweit ist ergänzendes Feedback (FB) zu erstellten Concept Maps lernwirksamer als die Erstellung von Concept Maps ohne ergänzendes Feedback? 2) Welches Feedback ist lernwirksamer: einfaches (EiFB) oder elaboriertes Feedback (ElFB)? 3) Inwieweit beeinflussen das Vorwissen, die Sprachfähigkeit, die Einschätzung des Umgangs mit Concept Mapping, die Einschätzung der Nützlichkeit des Feedbacks, die Einschätzung des Umgangs mit Fehlern sowie die Aufgabenanforderungen der Lernaufgabe die Lernwirksamkeit des Feedbacks? Die Untersuchung wurde im Rahmen des betriebswirtschaftlichen Planspielunterrichts durchgeführt. Ausgewählt wurde das von der BTI GmbH entwickelte Planspiel Easy BusinessTM, welches spielerisch den Wertschöpfungsprozess eines Produktionsunternehmens vermittelt und die Schüler die Folgen des Handelns in der jährlichen Rechnungslegung erleben lässt. Um die Lernwirksamkeit zu operationalisieren, wurde der Wissenserwerb anhand der Ergebnisse eines Paralleltests (Vortest, 1. Nachtest und 2. Nachtest) sowie anhand der Qualität der erstellten Maps analysiert. Auf diese Weise dienten die Concept Maps nicht nur der instruktionalen Unterstützung, sondern wurden auch zur Wissensdiagnose verwendet. Als Erhebungsinstrumente wurden weiterhin ein Sprachfähigkeitstest und ein Fragebogen zur Einschätzung des Umgangs mit Concept Mapping, der Nützlichkeit des Feedbacks sowie des Umgangs mit Fehlern eingesetzt. An der Feldstudie nahmen 83 Schülerinnen und Schüler achter und neunter Klassen zweier sächsischer Mittelschulen im Rahmen der Berufsvorbereitung teil. Das Durchschnittsalter betrug 13,9 Jahre. Die Untersuchung erstreckte sich über zwei Tage. Vor der Intervention wurde ein Vortest als Paralleltest (1. Teil des Paralleltests) und ein Sprachfähigkeitstest (Wilde-Intelligenz-Test 2) eingesetzt. In der abschließenden Testphase wurde der 1. Nachtest (2. Teil des Paralleltests) durchgeführt. Zusätzlich erhielten die Probanden einen Fragebogen, um die Methode des Concept Mapping und die Nützlichkeit des Feedbacks zu bewerten sowie den allgemeinen Umgang mit Fehlern einzuschätzen. Nach 9 Wochen wurde ein 2. Nachtest durchgeführt. Die Probanden wurden einer Kontrollgruppe (n=27), welche lediglich das Planspiel spielte, oder einer von drei Experimentalgruppen, kein FB (n=18), EiFB (n=18) oder ElFB (n=20), zugeordnet. In Vorbereitung auf die Untersuchung wurde die Methode des Concept Mapping eingeübt. Das Erstellen der Concept Maps wurde in den Planspielunterricht integriert. Dabei wurden von den Probanden der Experimentalgruppen insgesamt drei Mapping-Aktivitäten zu den wichtigsten Zusammenhängen durchgeführt. Die Gruppe kein FB erstellte lediglich die drei Concept Maps. Die Gruppe EiFB erhielt zusätzlich einfaches Feedback in Form des jeweiligen Referenzmaps als richtige Lösung. Nach jeder der drei Mapping-Aktivitäten wurde ein Referenzmap zur Verfügung gestellt, mit dem sich die Schüler intensiv auseinandersetzen sollten. Zusätzlich konnten sie in einer Kopie ihrer zuvor angefertigten Concept Maps Änderungen vornehmen. Die Gruppe ElFB erhielt ebenfalls einfaches Feedback in der beschriebenen Form. Darüber hinaus wurden Fehler exemplarisch anhand eines Schülernetzes sowie die drei Referenznetze in einem Lehrer-Schüler-Gespräch besprochen. Die Ergebnisse zeigen zunächst tendenziell, dass das Concept Mapping gegenüber der alleinigen Durchführung des Planspiels vorteilhaft ist. Bezogen auf das Feedback sind die Ergebnisse nicht eindeutig. Feedback (insbesondere elaboriertes Feedback) zu Concept Maps im betriebswirtschaftlichen Planspielunterricht scheint insbesondere für Probanden mit niedrigem Vorwissen und niedriger Sprachfähigkeit lernwirksam zu sein, wobei sich diese Effekte nur kurzfristig zeigen. Probanden, welche Feedback erhalten, sind in der Lage, Concept Maps mit einer höheren Qualität zu erstellen, als Probanden, welche kein Feedback erhalten. Dabei zeigt sich ein tendenzieller Vorteil des elaborierten gegenüber dem einfachen Feedback. Vor dem Einsatz der Methode Concept Mapping in Verbindung mit Feedback sollte daher das Vorwissen und die Sprachfähigkeit überprüft werden und entsprechend der Fähigkeiten Feedback angeboten werden. Um auch langfristige Effekte zu erzielen, ist es ratsam, die Methode Concept Mapping mehr zu üben und in den Lernprozess zu integrieren. Insbesondere im Unterrichtskontext könnten Lehrpersonen das Concept Mapping als kontinuierliche Methode einsetzen und in Abhängigkeit von individuellen Voraussetzungen und Aufgabenanforderungen um Feedback ergänzen. Die Anwendungsgebiete des Concept Mapping als Lernstrategie und als Diagnoseinstrument könnten dabei verbunden werden. Ergänzende Fehleranalysen der Maps könnten der Lehrperson helfen, falsche und fehlende Zusammenhänge zu identifizieren. Indem das Feedback entsprechend der Bedürfnisse der Lernenden mit der Methode des Concept Mapping verbunden wird, ist es somit möglich, den Planspielunterricht so zu unterstützen, dass eine Tiefenverarbeitung der erlernten Inhalte erreicht wird und die Lernenden auf die komplexen Anforderungen des beruflichen Alltags vorbereitet werden.:Inhaltsverzeichnis Abkürzungsverzeichnis Abbildungsverzeichnis Tabellenverzeichnis 1 Einleitung 2 Feedback in Lehr-Lernprozessen 2.1 Theoretische Grundlagen zum Feedback in Lehr-Lernprozessen 2.1.1 Bestimmung des Begriffs Feedback in Lehr-Lernprozessen 2.1.2 Funktionen und Ebenen von Feedback in Lehr-Lernprozessen 2.1.3 Klassifikation von Feedback in Lehr-Lernprozessen 2.1.3.1 Klassifikation von Feedback in Lehr-Lernprozessen anhand ausgewählter Kriterien 2.1.3.2 Klassifikation von Feedback in Lehr-Lernprozessen anhand des Kriteriums der Komplexität der Feedbacknachricht nach einfachem und elaboriertem Feedback 2.1.4 Feedbackmodelle zur Feedbackrezeption und/oder -gestaltung 2.1.4.1 Makromodelle von Kulhavy und Stock (1989) sowie von Bangert-Drowns u. a. (1991) 2.1.4.2 Mikromodell von Narciss (2006) 2.1.4.3 Rahmenmodell von Strijbos und Müller (2014) 2.1.4.4 Erweitertes Rahmenmodell zur Gestaltung und Verarbeitung von Feedback 2.2 Empirische Befunde zur Lernwirksamkeit des Feedbacks 2.2.1 Überblick über Metanalysen zur Lernwirksamkeit von Feedback 2.2.2 Studien zur Lernwirksamkeit des Feedbacks in Abhängigkeit von der Komplexität der Feedbacknachricht 2.2.3 Studien zur Lernwirksamkeit des Feedbacks in Abhängigkeit von der Feedback-Form 2.2.4 Studien zur Lernwirksamkeit des Feedbacks in Abhängigkeit von (inter-) personalen Faktoren 2.2.5 Studien zur Lernwirksamkeit des Feedbacks in Abhängigkeit von situativen Faktoren 2.2.6 Zusammenfassung der empirischen Befunde zur Lernwirksamkeit des Feedbacks 3 Concept Maps in Lehr-Lernprozessen 3.1 Theoretische Grundlagen zu Concept Maps in Lehr-Lernprozessen 3.1.1 Bestimmung des Begriffs und Klassifikation von Concept Maps 3.1.2 Anwendungsgebiete von Concept Maps in Lehr-Lernprozessen 3.1.3 Theoretische Ansätze zur Lernwirksamkeit von Concept Maps 3.2 Empirische Befunde zur Lernwirksamkeit von Concept Maps 3.2.1 Überblick über Metanalysen zur Lernwirksamkeit von Concept Maps 3.2.2 Studien zum Einfluss von Vorwissen, verbalen Voraussetzungen, kognitiven Fähigkeiten und dem Training der Methode auf die Lernwirksamkeit von Concept Maps 3.2.3 Studien zur Lernwirksamkeit von Feedback zu Concept Maps 4 Empirische Untersuchung zur Lernwirksamkeit von Feedback zu Concept Maps – Konzeption, Erhebung und Auswertung 4.1 Gestaltung der Untersuchung 4.1.1 Fragestellungen und Hypothesen 4.1.2 Stichprobe und Untersuchungsdesign 4.2 Gestaltung der Lernmaterialien und Interventionsmaßnahmen 4.2.1 Planspielunterricht mit Easy Business 4.2.2 Gestaltung des Concept Mapping 4.2.3 Gestaltung des Feedbacks 4.3 Erhebungsinstrumente 4.3.1 Wissenstest als Paralleltest 4.3.2 Sprachfähigkeitstest 4.3.3 Fragebogen zur Einschätzung des Umgangs mit Concept Mapping, der Nützlichkeit des Feedbacks sowie des Umgangs mit Fehlern 4.4 Auswertung der Wissenstests und des Sprachfähigkeitstests 4.4.1 Auswertung der Wissenstests 4.4.2 Auswertung des Sprachfähigkeitstests 4.5 Auswertung der Concept Maps 4.5.1 Kategoriale und strukturelle Inhaltsanalyse 4.5.2 Qualitative Bewertung der Concept Maps 4.6 Auswertung des Fragebogens zur Einschätzung des Umgangs mit Concept Mapping, des Umgangs mit Fehlern sowie der Nützlichkeit des Feedbacks 4.6.1 Auswertung des Teil-Fragebogens zur Einschätzung des Concept Mapping 4.6.2 Auswertung des Teil-Fragebogens zur Einschätzung der Nützlichkeit des Feedbacks 4.6.3 Auswertung des Teil-Fragebogens zur Einschätzung des Umgangs mit Fehlern 5 Empirische Untersuchung zur Lernwirksamkeit von Feedback zu Concept Maps – Analysen und Ergebnisse 5.1 Analysen zum Einfluss der Art des Feedbacks 5.1.1 Analysen zum Einfluss der Art des Feedbacks auf den Wissenserwerb 5.1.1.1 Analyse der Lernwirksamkeit des Concept Mapping 5.1.1.2 Gruppenunterschiede hinsichtlich des Wissenserwerbs 5.1.1.3 Einfluss von personalen und weiteren Faktoren auf den Wissenserwerb 5.1.1.3.1 Einfluss von Vorwissen, Sprachfähigkeit, der Einschätzung zum Umgang mit Concept Mapping und zum Umgang mit Fehlern auf den Wissenserwerb 5.1.1.3.2 Einfluss von niedrigem bzw. hohem Vorwissen auf den Wissenserwerb 5.1.1.3.3 Einfluss von niedriger bzw. hoher Sprachfähigkeit auf den Wissenserwerb 5.1.1.4 Einfluss des Lernzielniveaus auf den Wissenserwerb 5.1.1.4.1 Gruppenunterschiede hinsichtlich des Wissenserwerbs für einfache Aufgaben 5.1.1.4.2 Gruppenunterschiede hinsichtlich des Wissenserwerbs für komplexe Aufgaben 5.1.1.5 Einfluss von personalen und weiteren Faktoren auf den Wissenserwerb einfacher bzw. komplexer Aufgaben 5.1.1.6 Zusammenfassung der Ergebnisse und Bewertung der Hypothesen hinsichtlich des Wissenserwerbs 5.1.2 Einfluss der Art des Feedbacks auf die Qualität der Maps 5.1.2.1 Gruppenunterschiede hinsichtlich der Map-Qualität 5.1.2.2 Einfluss des Vorwissens, der Sprachfähigkeit, der Einschätzung zum Umgang mit Concept Mapping und zum Umgang mit Fehlern auf die Qualität der Maps 5.1.2.3 Zusammenfassung der Ergebnisse und Bewertung der Hypothesen hinsichtlich der Qualität der Maps 5.1.3 Einfluss der Qualität der Maps auf den Wissenserwerb 5.1.3.1 Einfluss der Qualität des 1., 2. und 3. Maps auf den 1. bzw. 2. Nachtest 5.1.3.2 Einfluss von niedriger bzw. hoher Qualität des 2. Maps auf den Wissenserwerb 5.1.3.3 Einfluss von niedriger bzw. hoher Qualität des 3. Maps auf den Wissenserwerb 5.1.3.4 Einfluss der Qualität des 1., 2. und 3. Maps auf den Wissenserwerb einfacher und komplexer Aufgaben 5.1.3.5 Zusammenfassung der Ergebnisse und Bewertung der Hypothesen zum Einfluss der Qualität der Maps auf den Wissenserwerb 5.2 Analysen zum Umgang mit dem Feedback sowie Analyse der Fehler in den Concept Maps 5.2.1 Analysen zum Umgang mit dem Feedback 5.2.2 Analysen der Fehler in den Concept Maps 5.2.3 Zusammenfassung der Ergebnisse zum Umgang mit dem Feedback und der Fehleranalyse 5.3 Interpretation der Ergebnisse 6 Schlussbetrachtung 6.1 Zusammenfassung 6.2 Kritische Würdigung, Optimierungsvorschläge und Ausblick Literaturverzeichnis
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Syntax-based Concept Extraction For Question Answering

Glinos, Demetrios 01 January 2006 (has links)
Question answering (QA) stands squarely along the path from document retrieval to text understanding. As an area of research interest, it serves as a proving ground where strategies for document processing, knowledge representation, question analysis, and answer extraction may be evaluated in real world information extraction contexts. The task is to go beyond the representation of text documents as "bags of words" or data blobs that can be scanned for keyword combinations and word collocations in the manner of internet search engines. Instead, the goal is to recognize and extract the semantic content of the text, and to organize it in a manner that supports reasoning about the concepts represented. The issue presented is how to obtain and query such a structure without either a predefined set of concepts or a predefined set of relationships among concepts. This research investigates a means for acquiring from text documents both the underlying concepts and their interrelationships. Specifically, a syntax-based formalism for representing atomic propositions that are extracted from text documents is presented, together with a method for constructing a network of concept nodes for indexing such logical forms based on the discourse entities they contain. It is shown that meaningful questions can be decomposed into Boolean combinations of question patterns using the same formalism, with free variables representing the desired answers. It is further shown that this formalism can be used for robust question answering using the concept network and WordNet synonym, hypernym, hyponym, and antonym relationships. This formalism was implemented in the Semantic Extractor (SEMEX) research tool and was tested against the factoid questions from the 2005 Text Retrieval Conference (TREC), which operated upon the AQUAINT corpus of newswire documents. After adjusting for the limitations of the tool and the document set, correct answers were found for approximately fifty percent of the questions analyzed, which compares favorably with other question answering systems.

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