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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.
11

Soar to Success: An Instructional Inquiry on a Reading Comprehension Curriculum for Students with Significant Reading Deficits

Buhlman, Tina Bisaro January 2017 (has links)
No description available.
12

Prediction of the vibroacoustic response of aerospace composite structures in a broadband frequency range

Chronopoulos, Dimitrios 29 November 2012 (has links)
Pendant sa mission, un lanceur est soumis à des excitations large bande, sévères, aérodynamiques, de provenances diverses, qui peuvent mettre en danger la survivabilité de la charge utile et de l’équipement électronique du véhicule, et par conséquent le succès de la mission. Les structures aérospatiales sont généralement caractérisées par l’utilisation de matériaux composites exotiques des configurations et des épaisseurs variantes, ainsi que par leurs géométries largement complexes. Il est donc d’une importance cruciale pour l’industrie aérospatiale moderne, le développement d’outils analytiques et numériques qui peuvent prédire avec précision la réponse vibroacoustique des structures larges, composites de différentes géométries et soumis à une combinaison des excitations aéroacoustiques. Récemment, un grand nombre de recherches ont été menées sur la modélisation des caractéristiques de propagation des ondes au sein des structures composites. Dans cette étude, la méthode des éléments finis ondulatoires (WFEM) est utilisée afin de prédire les caractéristiques de dispersion des ondes dans des structures composites orthotropes de géométries variables, nommément des plaques plates, des panneaux simplement courbés, des panneaux doublement courbés et des coques cylindriques. Ces caractéristiques sont initialement utilisées pour prédire la densité modale et le facteur de perte par couplage des structures connectées au milieu acoustique. Par la suite, la perte de transmission (TL) à large bande des structures modélisées dans le cadre d’une analyse statistique énergétique (SEA) dans un contexte ondulatoire est calculée. Principalement en raison de la complexité géométrique importante de structures, l’utilisation des éléments finis (FE) au sein de l’industrie aérospatiale est souvent inévitable. L’utilisation de ces modèles est limitée principalement à cause du temps de calcul exigé, même pour les calculs dans la bande basses fréquences. Au cours des dernières années, beaucoup de chercheurs travaillent sur la réduction de modèles FE, afin de rendre leur application possible pour des systèmes larges. Dans cette étude, l’approche de SOAR est adoptée, afin de minimiser le temps de calcul pour un système couplé de type structurel-acoustique, tout en conservant une précision satisfaisante de la prédiction dans un sens large bande. Le système est modélisé sous diverses excitations aéroacoustiques, nommément un champ acoustique diffus et une couche limite turbulente (TBL).La validation expérimentale des outils développés est réalisée sur un ensemble de structures sandwich composites orthotropes. Ces derniers sont utilisés afin de formuler une approche couche équivalente unique (ESL) pour la modélisation de la réponse spatiale du panneau dans le contexte d’une approche de matrice de raideur dynamique. L’effet de la température de la structure ainsi que du milieu acoustique sur la réponse du système vibroacoustique est examiné et analysé. Par la suite, un modèle de la structure SYLDA, également fait d’un matériau sandwich orthotrope, est testé principalement dans le but d’enquêter sur la nature de couplage entre ses divers sous-systèmes. La modélisation ESL précédemment développée est utilisé pour un calcul efficace de la réponse de la structure dans la gamme des basses et moyennes fréquences, tandis que pour des fréquences plus élevées, une hybridisation WFEM / FEM pour la modélisation des structures discontinues est utilisé. / During its mission, a launch vehicle is subject to broadband, severe, aeroacoustic and structure-borne excitations of various provenances, which can endanger the survivability of the payload and the vehicles electronic equipment, and consequently the success of the mission. Aerospace structures are generally characterized by the use of exotic composite materials of various configurations and thicknesses, as well as by their extensively complex geometries and connections between different subsystems. It is therefore of crucial importance for the modern aerospace industry, the development of analytical and numerical tools that can accurately predict the vibroacoustic response of large, composite structures of various geometries and subject to a combination of aeroacoustic excitations. Recently, a lot of research has been conducted on the modelling of wave propagation characteristics within composite structures. In this study, the Wave Finite Element Method (WFEM) is used in order to predict the wave dispersion characteristics within orthotropic composite structures of various geometries, namely flat panels, singly curved panels, doubly curved panels and cylindrical shells. These characteristics are initially used for predicting the modal density and the coupling loss factor of the structures connected to the acoustic medium. Subsequently the broad-band Transmission Loss (TL) of the modelled structures within a Statistical Energy Analysis (SEA) wave-context approach is calculated. Mainly due to the extensive geometric complexity of structures, the use of Finite Element(FE) modelling within the aerospace industry is frequently inevitable. The use of such models is limited mainly because of the large computation time demanded even for calculations in the low frequency range. During the last years, a lot of researchers focus on the model reduction of large FE models, in order to make their application feasible. In this study, the Second Order ARnoldi (SOAR) reduction approach is adopted, in order to minimize the computation time for a fully coupled composite structural-acoustic system, while at the same time retaining a satisfactory accuracy of the prediction in a broadband sense. The system is modelled under various aeroacoustic excitations, namely a diffused acoustic field and a Turbulent Boundary Layer (TBL) excitation. Experimental validation of the developed tools is conducted on a set of orthotropic sandwich composite structures. Initially, the wave propagation characteristics of a flat panel are measured and the experimental results are compared to the WFEM predictions. The later are used in order to formulate an Equivalent Single Layer (ESL) approach for the modelling of the spatial response of the panel within a dynamic stiffness matrix approach. The effect of the temperature of the structure as well as of the acoustic medium on the vibroacoustic response of the system is examined and analyzed. Subsequently, a model of the SYLDA structure, also made of an orthotropic sandwich material, is tested mainly in order to investigate the coupling nature between its various subsystems. The developed ESL modelling is used for an efficient calculation of the response of the structure in the lower frequency range, while for higher frequencies a hybrid WFEM/FEM formulation for modelling discontinuous structures is used.
13

具SOAR結構化筆記功能之合作數位閱讀標註系統對於國小學生閱讀理解成效之影響研究 / A study on the effects of collaborative reading annotation system with soar structured note function on reading comprehension performance

陳怡君, Chen,Yi Chun Unknown Date (has links)
因應數位閱讀時代的來臨,在進行數位閱讀時,如何進行自我監控,協助學習者掌握閱讀技巧,特別是對於閱讀認知能力不足的小學兒童來說,在進行數位閱讀時更需要有完善的學習鷹架輔助,才能達到良好的閱讀成效。標註系統中也發展出許多不同機制來輔助閱讀,幫助提升學習者的閱讀動機與閱讀成效。但卻也發現學習容易著重在標註的量而忽略了標註的品質,反而無法提升其閱讀理解成效,在學習的過程中忽略了閱讀歷程與閱讀認知的適配性。因此,本研究在合作式數位閱讀標註系統上發展出一套基於閱讀標註支援更有效閱讀的「SOAR結構式筆記模組」,讓學習者於作筆記的過程中掌握文本的重點,幫助學習者提升其閱讀自我效能,希望可有效促進學習者在閱讀中有效的內化與重組,以提升閱讀理解的深度與成效。 本研究採單組實驗設計,探討學習者在使用具「SOAR結構化筆記模組」的「合作式數位閱讀標註系統」輔以閱讀學習的情境下,學習者的閱讀標註瀏覽行為、標註行為及SOAR筆記分數是否影響學生其閱讀自我效能、閱讀理解成效。此外,也針對不同性別與認知風格的學習者作探討。 研究結果發現: 1.在使用「合作式數位閱讀標註系統」支援閱讀的學習情境下,採用「SOAR結構化筆記模組」支援數位閱讀學習,其國小學生的標註行為、閱讀標註瀏覽行為及SOAR筆記分數與閱讀自我效能並無顯著相關2.女性學習者的自我效能與閱讀理解成效具有顯著高度正相關,並且具有線性迴歸之可預測性3.全體學習者的SOAR筆記分數與閱讀理解成具有顯著高度正相關,並且具有線性迴歸之可預測性4.男性學習者的SOAR筆記分數與閱讀理解成效具有顯著高度正相關,並且具有線性迴歸之可預測性5.對國小學生的閱讀理解成效具有顯著的提升6.對男性學習者與女性學習者的閱讀理解成效均具有顯著的提升7.對場地獨立型學習者與場地相依型的學習者的閱讀理解成效均具有顯著的提升。 最後,基於研究結果,本研究亦提出對教師及系統改良的建議,並提出幾個未來的研究方向,希望能對數位閱讀研究有所貢獻。 / Abstract To cope with the digital reading era, self-monitoring to assist learners in grasping reading skills during digital reading, especially for the digital reading of elementary pupils with inadequate reading cognitive capabilities, perfect learning scaffolding is required for achieving good reading performance. There are many different mechanisms developed in annotation systems to assist in reading and help learners promote the reading motivation and reading performance. However, it is also discovered that the learning could easily focus on the quantity of annotation, but ignore the quality of annotation so that the reading comprehension performance could not be enhanced and the suitability of reading process and reading cognition in the learning process is ignored. For this reason, a reading annotation based “SOAR structured note module” for supporting effective reading is developed on the cooperative digital reading annotation system, allowing learners grasping the key points in the text during the noting process and helping learners promote the reading self-efficacy. It is expected to effectively advance the effective internalization and organization of learners in the reading in order to enhance the depth and performance of reading comprehension. With one-shot experimental design, the effect of learners’ reading annotation browsing behaviors, annotation behaviors, and SOAR note scores on the reading self-efficacy and reading comprehension performance, under the reading learning situation with “cooperative digital reading annotation system” with “SOAR structured note module”. Besides, gender and learners with different cognitive styles are also discussed in this study. The research findings are concluded as below. 1. Under the reading learning situation with the support of “cooperative digital reading annotation system”, elementary students applying “SOAR structured note module” to support the digital reading learning do not appear significant correlations between annotation behaviors, reading annotation browsing behaviors, SOAR note scores and reading self-efficacy. 2. Female learners’ self-efficacy and reading comprehension performance present remarkably and highly positive correlations, with the predictability of linear regression. 3. All learners’ SOAR note scores and reading comprehension performance show significantly and highly positive correlation, with the predictability of linear regression. 4. Male learners’ SOAR note scores and reading comprehension performance reveal notably and highly positive correlation, with the predictability of linear regression. 5. Elementary students’ reading comprehension performance is remarkably enhanced. 6. Both male and female learners’ reading comprehension performance is significantly enhanced. 7. Both field-independent and field-dependent learners’ reading comprehension performance is notably enhanced. Finally, suggestions for teachers and system improvement are proposed, based on the research results, in this study, and several research directions are also proposed for research on digital reading. Key words: SOAR structured note; cooperative reading annotation; reading self-efficacy; reading comprehension performance
14

Simulating the effects of mental workload on tactical and operational performance in tankcrew

Lundin, Mikael January 2004 (has links)
<p>Battletank crew must perform many diverse tasks during a normal mission: Crewmembers have to navigate, communicate, control on-board systems, and engage with the enemy, to mention a few. As human processing capacity is limited, the crewmembers will find themselves in situations where task requirements, due to the number of tasks and task complexity, exceed their mental capacity. The stress that results from mental overload has documented quantitative and qualitative effects on performance; effects that could lead to mission failure. </p><p>This thesis describes a simulation of tankcrew during a mission where mental workload is a key factor to the outcome of mission performance. The thesis work has given rise to a number of results. First, conceptual models have been developed of the tank crewmembers. Mental workload is represented in these models as a behavior moderator, which can be manipulated to demonstrate and predict behavioral effects. Second, cognitive models of the tank crewmembers are implemented as Soar agents, which interact with tanks in a 3D simulated battlefield. The empirical data underlying these models was collected from experiments with tankcrew, and involved first hand observations and task analyses. Afterwards, the model’s behavior was verified against an a priori established behavioral pattern and successfully face validated with two subject matter experts.</p>
15

Simulating the effects of mental workload on tactical and operational performance in tankcrew

Lundin, Mikael January 2004 (has links)
Battletank crew must perform many diverse tasks during a normal mission: Crewmembers have to navigate, communicate, control on-board systems, and engage with the enemy, to mention a few. As human processing capacity is limited, the crewmembers will find themselves in situations where task requirements, due to the number of tasks and task complexity, exceed their mental capacity. The stress that results from mental overload has documented quantitative and qualitative effects on performance; effects that could lead to mission failure. This thesis describes a simulation of tankcrew during a mission where mental workload is a key factor to the outcome of mission performance. The thesis work has given rise to a number of results. First, conceptual models have been developed of the tank crewmembers. Mental workload is represented in these models as a behavior moderator, which can be manipulated to demonstrate and predict behavioral effects. Second, cognitive models of the tank crewmembers are implemented as Soar agents, which interact with tanks in a 3D simulated battlefield. The empirical data underlying these models was collected from experiments with tankcrew, and involved first hand observations and task analyses. Afterwards, the model’s behavior was verified against an a priori established behavioral pattern and successfully face validated with two subject matter experts.
16

Performance Enhancement of Data Retrieval from Episodic Memory in Soar Architecture

BHUJEL, MAN BAHADUR 14 December 2018 (has links)
No description available.
17

Prediction of the vibroacoustic response of aerospace composite structures in a broadband frequency range

Chronopoulos, Dimitrios 29 November 2012 (has links) (PDF)
During its mission, a launch vehicle is subject to broadband, severe, aeroacoustic and structure-borne excitations of various provenances, which can endanger the survivability of the payload and the vehicles electronic equipment, and consequently the success of the mission. Aerospace structures are generally characterized by the use of exotic composite materials of various configurations and thicknesses, as well as by their extensively complex geometries and connections between different subsystems. It is therefore of crucial importance for the modern aerospace industry, the development of analytical and numerical tools that can accurately predict the vibroacoustic response of large, composite structures of various geometries and subject to a combination of aeroacoustic excitations. Recently, a lot of research has been conducted on the modelling of wave propagation characteristics within composite structures. In this study, the Wave Finite Element Method (WFEM) is used in order to predict the wave dispersion characteristics within orthotropic composite structures of various geometries, namely flat panels, singly curved panels, doubly curved panels and cylindrical shells. These characteristics are initially used for predicting the modal density and the coupling loss factor of the structures connected to the acoustic medium. Subsequently the broad-band Transmission Loss (TL) of the modelled structures within a Statistical Energy Analysis (SEA) wave-context approach is calculated. Mainly due to the extensive geometric complexity of structures, the use of Finite Element(FE) modelling within the aerospace industry is frequently inevitable. The use of such models is limited mainly because of the large computation time demanded even for calculations in the low frequency range. During the last years, a lot of researchers focus on the model reduction of large FE models, in order to make their application feasible. In this study, the Second Order ARnoldi (SOAR) reduction approach is adopted, in order to minimize the computation time for a fully coupled composite structural-acoustic system, while at the same time retaining a satisfactory accuracy of the prediction in a broadband sense. The system is modelled under various aeroacoustic excitations, namely a diffused acoustic field and a Turbulent Boundary Layer (TBL) excitation. Experimental validation of the developed tools is conducted on a set of orthotropic sandwich composite structures. Initially, the wave propagation characteristics of a flat panel are measured and the experimental results are compared to the WFEM predictions. The later are used in order to formulate an Equivalent Single Layer (ESL) approach for the modelling of the spatial response of the panel within a dynamic stiffness matrix approach. The effect of the temperature of the structure as well as of the acoustic medium on the vibroacoustic response of the system is examined and analyzed. Subsequently, a model of the SYLDA structure, also made of an orthotropic sandwich material, is tested mainly in order to investigate the coupling nature between its various subsystems. The developed ESL modelling is used for an efficient calculation of the response of the structure in the lower frequency range, while for higher frequencies a hybrid WFEM/FEM formulation for modelling discontinuous structures is used.
18

Integrative Ecosystem Management: Designing Cities and Co-creating the Flourishing Ecosystem

Clay, Larry Clinton, Jr 01 September 2021 (has links)
No description available.
19

Entwurf einer fehlerüberwachten Modellreduktion basierend auf Krylov-Unterraumverfahren und Anwendung auf ein strukturmechanisches Modell / Implementation of an error-controlled model reduction based on Krylov-subspace methods and application to a mechanical model

Bernstein, David 17 October 2014 (has links) (PDF)
Die FEM-MKS-Kopplung erfordert Modellordnungsreduktions-Verfahren, die mit kleiner reduzierter Systemdimension das Übertragungsverhalten mechanischer Strukturen abbilden. Rationale Krylov-Unterraum-Verfahren, basierend auf dem Arnoldi-Algorithmen, ermöglichen solche Abbildungen in frei wählbaren, breiten Frequenzbereichen. Ziel ist der Entwurf einer fehlerüberwachten Modelreduktion auf Basis von Krylov-Unterraumverfahren und Anwendung auf ein strukturmechanisches Model. Auf Grundlage der Software MORPACK wird eine Arnoldi-Funktion erster Ordnung um interpolativen Startvektor, Eliminierung der Starrkörperbewegung und Reorthogonalisierung erweitert. Diese Operationen beinhaltend, wird ein rationales, interpolatives SOAR-Verfahren entwickelt. Ein rationales Block-SOAR-Verfahren erweist sich im Vergleich als unterlegen. Es wird interpolative Gleichwichtung verwendet. Das Arnoldi-Verfahren zeichnet kleiner Berechnungsaufwand aus. Das rationale, interpolative SOAR liefert kleinere reduzierte Systemdimensionen für gleichen abgebildeten Frequenzbereich. Die Funktionen werden auf Rahmen-, Getriebegehäuse- und Treibsatzwellen-Modelle angewendet. Zur Fehlerbewertung wird eigenfrequenzbasiert ein H2-Integrationsbereich festgelegt und der übertragungsfunktionsbasierte, relative H2-Fehler berechnet. Es werden zur Lösung linearer Gleichungssysteme mit Matlab entsprechende Löser-Funktionen, auf Permutation und Faktorisierung basierend, implementiert. / FEM-MKS-coupling requires model order reduction methods to simulate the frequency response of mechanical structures using a smaller reduced representation of the original system. Most of the rational Krylov-subspace methods are based on Arnoldi-algorithms. They allow to represent the frequency response in freely selectable, wide frequency ranges. Subject of this thesis is the implementation of an error-controlled model order reduction based on Krylov-subspace methods and the application to a mechanical model. Based on the MORPACK software, a first-order-Arnoldi function is extended by an interpolative start vector, the elimination of rigid body motion and a reorthogonalization. Containing these functions, a rational, interpolative Second Order Arnoldi (SOAR) method is designed that works well compared to a rational Block-SOAR-method. Interpolative equal weighting is used. The first-order-Arnoldi method requires less computational effort compared to the rational, interpolative SOAR that is able to compute a smaller reduction size for same frequency range of interest. The methods are applied to the models of a frame, a gear case and a drive shaft. Error-control is realized by eigenfrequency-based H2-integration-limit and relative H2-error based on the frequency response function. For solving linear systems of equations in Matlab, solver functions based on permutation and factorization are implemented.
20

Entwurf einer fehlerüberwachten Modellreduktion basierend auf Krylov-Unterraumverfahren und Anwendung auf ein strukturmechanisches Modell

Bernstein, David 04 June 2014 (has links)
Die FEM-MKS-Kopplung erfordert Modellordnungsreduktions-Verfahren, die mit kleiner reduzierter Systemdimension das Übertragungsverhalten mechanischer Strukturen abbilden. Rationale Krylov-Unterraum-Verfahren, basierend auf dem Arnoldi-Algorithmen, ermöglichen solche Abbildungen in frei wählbaren, breiten Frequenzbereichen. Ziel ist der Entwurf einer fehlerüberwachten Modelreduktion auf Basis von Krylov-Unterraumverfahren und Anwendung auf ein strukturmechanisches Model. Auf Grundlage der Software MORPACK wird eine Arnoldi-Funktion erster Ordnung um interpolativen Startvektor, Eliminierung der Starrkörperbewegung und Reorthogonalisierung erweitert. Diese Operationen beinhaltend, wird ein rationales, interpolatives SOAR-Verfahren entwickelt. Ein rationales Block-SOAR-Verfahren erweist sich im Vergleich als unterlegen. Es wird interpolative Gleichwichtung verwendet. Das Arnoldi-Verfahren zeichnet kleiner Berechnungsaufwand aus. Das rationale, interpolative SOAR liefert kleinere reduzierte Systemdimensionen für gleichen abgebildeten Frequenzbereich. Die Funktionen werden auf Rahmen-, Getriebegehäuse- und Treibsatzwellen-Modelle angewendet. Zur Fehlerbewertung wird eigenfrequenzbasiert ein H2-Integrationsbereich festgelegt und der übertragungsfunktionsbasierte, relative H2-Fehler berechnet. Es werden zur Lösung linearer Gleichungssysteme mit Matlab entsprechende Löser-Funktionen, auf Permutation und Faktorisierung basierend, implementiert.:1. Einleitung 1.1. Motivation 1.2. Einordnung 1.3. Aufbau der Arbeit 2. Theorie 2.1. Simulationsmethoden 2.1.1. Finite Elemente Methode 2.1.2. Mehrkörpersimulation 2.1.3. Kopplung der Simulationsmethoden 2.2. Zustandsraumdarstellung und Reduktion 2.3. Krylov Unterraum Methoden 2.4. Arnoldi-Algorithmen erster Ordnung 2.5. Arnoldi-Algorithmen zweiter Ordnung 2.6. Korrelationskriterien 2.6.1. Eigenfrequenzbezogene Kriterien 2.6.2. Eigenvektorbezogene Kriterien 2.6.3. Übertragungsfunktionsbezogene Kriterien 2.6.4. Fehlerbewertung 2.6.5. Anwendung auf Systeme sehr großer Dimension 3. Numerik linearer Gleichungssysteme 3.1. Grundlagen 3.2. Singularität der Koeffizientenmatrix 3.2.1. Randbedingungen des Systems 3.2.2. Verwendung einer generellen Diagonalperturbation 3.3. Iterative Lösungsverfahren 3.4. Faktorisierungsverfahren 3.4.1. Cholesky-Faktorisierung 3.4.2. LU-Faktorisierung 3.4.3. Fillin-Reduktion durch Permutation 3.4.4. Fazit 3.5. Direkte Lösungsverfahren 3.6. Verwendung externer Gleichungssystem-Löser 3.7. Zusammenfassung 4. Implementierung 4.1. Aufbau von MORPACK 4.2. Anforderungen an Reduktions-Funktionen 4.3. Eigenschaften und Optionen der KSM-Funktionen 4.3.1. Arnoldi-Funktion erster Ordnung 4.3.2. Rationale SOAR-Funktionen 4.4. Korrelationskriterien 4.4.1. Eigenfrequenzbezogen 4.4.2. Eigenvektorbezogen 4.4.3. Übertragungsfunktionsbezogen 4.5. Lösungsfunktionen linearer Gleichungssysteme 4.5.1. Anforderungen und Aufbau 4.5.2. Verwendung der Gleichungssystem-Löser 4.5.3. Hinweise zur Implementierung von Gleichungssystem-Lösern 5. Anwendung 5.1. Versuchsmodelle 5.1.1. Testmodelle kleiner Dimension 5.1.2. Getriebegehäuse 5.1.3. Treibsatzwelle 5.2. Validierung der Reduktionsmethoden an kleinem Modell 5.2.1. Modifizierte Arnoldi-Funktion erster Ordnung 5.2.2. Rationale SOAR-Funktionen 5.2.3. Zusammenfassung 5.3. Anwendung der KSM auf große Modelle 5.3.1. Getriebegehäuse 5.3.2. Treibsatzwelle 5.4. Auswertung 6. Zusammenfassung und Ausblick 6.1. Zusammenfassung 6.2. Ausblick / FEM-MKS-coupling requires model order reduction methods to simulate the frequency response of mechanical structures using a smaller reduced representation of the original system. Most of the rational Krylov-subspace methods are based on Arnoldi-algorithms. They allow to represent the frequency response in freely selectable, wide frequency ranges. Subject of this thesis is the implementation of an error-controlled model order reduction based on Krylov-subspace methods and the application to a mechanical model. Based on the MORPACK software, a first-order-Arnoldi function is extended by an interpolative start vector, the elimination of rigid body motion and a reorthogonalization. Containing these functions, a rational, interpolative Second Order Arnoldi (SOAR) method is designed that works well compared to a rational Block-SOAR-method. Interpolative equal weighting is used. The first-order-Arnoldi method requires less computational effort compared to the rational, interpolative SOAR that is able to compute a smaller reduction size for same frequency range of interest. The methods are applied to the models of a frame, a gear case and a drive shaft. Error-control is realized by eigenfrequency-based H2-integration-limit and relative H2-error based on the frequency response function. For solving linear systems of equations in Matlab, solver functions based on permutation and factorization are implemented.:1. Einleitung 1.1. Motivation 1.2. Einordnung 1.3. Aufbau der Arbeit 2. Theorie 2.1. Simulationsmethoden 2.1.1. Finite Elemente Methode 2.1.2. Mehrkörpersimulation 2.1.3. Kopplung der Simulationsmethoden 2.2. Zustandsraumdarstellung und Reduktion 2.3. Krylov Unterraum Methoden 2.4. Arnoldi-Algorithmen erster Ordnung 2.5. Arnoldi-Algorithmen zweiter Ordnung 2.6. Korrelationskriterien 2.6.1. Eigenfrequenzbezogene Kriterien 2.6.2. Eigenvektorbezogene Kriterien 2.6.3. Übertragungsfunktionsbezogene Kriterien 2.6.4. Fehlerbewertung 2.6.5. Anwendung auf Systeme sehr großer Dimension 3. Numerik linearer Gleichungssysteme 3.1. Grundlagen 3.2. Singularität der Koeffizientenmatrix 3.2.1. Randbedingungen des Systems 3.2.2. Verwendung einer generellen Diagonalperturbation 3.3. Iterative Lösungsverfahren 3.4. Faktorisierungsverfahren 3.4.1. Cholesky-Faktorisierung 3.4.2. LU-Faktorisierung 3.4.3. Fillin-Reduktion durch Permutation 3.4.4. Fazit 3.5. Direkte Lösungsverfahren 3.6. Verwendung externer Gleichungssystem-Löser 3.7. Zusammenfassung 4. Implementierung 4.1. Aufbau von MORPACK 4.2. Anforderungen an Reduktions-Funktionen 4.3. Eigenschaften und Optionen der KSM-Funktionen 4.3.1. Arnoldi-Funktion erster Ordnung 4.3.2. Rationale SOAR-Funktionen 4.4. Korrelationskriterien 4.4.1. Eigenfrequenzbezogen 4.4.2. Eigenvektorbezogen 4.4.3. Übertragungsfunktionsbezogen 4.5. Lösungsfunktionen linearer Gleichungssysteme 4.5.1. Anforderungen und Aufbau 4.5.2. Verwendung der Gleichungssystem-Löser 4.5.3. Hinweise zur Implementierung von Gleichungssystem-Lösern 5. Anwendung 5.1. Versuchsmodelle 5.1.1. Testmodelle kleiner Dimension 5.1.2. Getriebegehäuse 5.1.3. Treibsatzwelle 5.2. Validierung der Reduktionsmethoden an kleinem Modell 5.2.1. Modifizierte Arnoldi-Funktion erster Ordnung 5.2.2. Rationale SOAR-Funktionen 5.2.3. Zusammenfassung 5.3. Anwendung der KSM auf große Modelle 5.3.1. Getriebegehäuse 5.3.2. Treibsatzwelle 5.4. Auswertung 6. Zusammenfassung und Ausblick 6.1. Zusammenfassung 6.2. Ausblick

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