• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 179
  • 76
  • 40
  • 31
  • 22
  • 19
  • 12
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • Tagged with
  • 483
  • 99
  • 56
  • 53
  • 44
  • 33
  • 30
  • 29
  • 27
  • 25
  • 25
  • 24
  • 23
  • 22
  • 21
  • 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.
351

Programming by demonstration of robot manipulators

Skoglund, Alexander January 2009 (has links)
If a non-expert wants to program a robot manipulator he needs a natural interface that does not require rigorous robot programming skills. Programming-by-demonstration (PbD) is an approach which enables the user to program a robot by simply showing the robot how to perform a desired task. In this approach, the robot recognizes what task it should perform and learn how to perform it by imitating the teacher. One fundamental problem in imitation learning arises from the fact that embodied agents often have different morphologies. Thus, a direct skill transfer from human to a robot is not possible in the general case. Therefore, we need a systematic approach to PbD that takes the capabilities of the robot into account–regarding both perception and body structure. In addition, the robot should be able to learn from experience and improve over time. This raises the question of how to determine the demonstrator’s goal or intentions. We show that this is possible–to some degree–to infer from multiple demonstrations. We address the problem of generation of a reach-to-grasp motion that produces the same results as a human demonstration. It is also of interest to learn what parts of a demonstration provide important information about the task. The major contribution is the investigation of a next-state-planner using a fuzzy time-modeling approach to reproduce a human demonstration on a robot. We show that the proposed planner can generate executable robot trajectories based on a generalization of multiple human demonstrations. We use the notion of hand-states as a common motion language between the human and the robot. It allows the robot to interpret the human motions as its own, and it also synchronizes reaching with grasping. Other contributions include the model-free learning of human to robot mapping, and how an imitation metric ca be used for reinforcement learning of new robot skills. The experimental part of this thesis presents the implementation of PbD of pick-and-place-tasks on different robotic hands/grippers. The different platforms consist of manipulators and motion capturing devices.
352

Small hepatitis Delta antigen mimics a histone H3 epitope to facilitate the remodeling of the Hepatitis D virus (HDV) viral ribonucleoprotein / La petite protéine du virus de l’hépatite Delta (HDV) imite un épitope de l’histone H3 pour faciliter le remodelage de la ribonucléoprotéine virale pour la réplication de l’ARN viral

Abeywickrama Samarakoon, Natali 20 October 2016 (has links)
Le virus de l'hépatite Delta (HDV) est un agent infectieux transmissible satellite du virus de l'hépatite B (HBV), induisant des maladies du foie plus sévères que la mono–infection par le HBV. Aucun traitement totalement efficace n'est disponible contre l'HDV et les 15 millions de personnes infectées par le HDV dans le monde sont exposées a un risque élevé de cirrhose et de carcinome hépatocellulaire. HDV est un virus unique qui ne code pas pour une polymérase virale contrairement aux autres virus a ARN. La réplication de l'ARN HDV s'effectue par un double mécanisme de cercle roulant générant des brins d'ARN de longueur génomique ou antigénomiques unitaires. La synthèse de l'ARN génomique est sensible à de faibles concentrations d'alpha–amanitine, ce qui suggère qu'elle soit médiée par l'ARN polymérase II (ARN Pol II) classiquement ADN dépendante. Ce processus repose sur la petite protéine du HDV (S–HDAg), qui doit être acétylée sur l'acide amine K72 pour activer la synthèse de l'ARN génomique. Nous avons récemment identifié la protéine BAZ2B (Bromodomain Associated Zinc finger protein 2B) comme un interactant majeur de S–HDAg par capture par affinité, couplée à la spectrométrie de masse à partir de l'expression de S– HDAg étiqueté par un double motif Strep–TagR dans les cellules HepaRG différentiées. La fonction biologique de BAZ2B est inconnue. Cependant, en comparant avec des protéines apparentées BAZ (BAZ–1A/1B/2A), on postule que BAZ2B représente la sous–unité accessoire d'un nouveau complexe de remodelage de chromatine de type ISWI, qui régule le positionnement des nucléosomes par hydrolyse de l'ATP. Des études récentes ont révélé que le bromodomaine de BAZ2B (BRD) reconnait la signature épigénétique spécifique K14ac–X–X–R sur l'histone H3. Cela pourrait impliquer le mode d'action du complexe de remodelage de la chromatine dont BAZ2B représente l'unité régulatrice reconnaissant des marques spécifiques d'acétylation des histones propagées séquentiellement modifiant la dynamique de la chromatine et favorisant le recrutement de l'ARN Pol II pour activer la transcription. Nous émettons l'hypothèse que l'acétylation, médiée par p300, du motif K72–X–X–R conserve dans les S–HDAg interagissant avec l'ARN antigénomique pseudo double brin, mimerait l'acétylation des histone H3 en K14 permettant de recruter le complexe de remodelage de la chromatine BAZ2B associée et de lancer la réplication HDV. Brièvement, pour confirmer la pertinence fonctionnelle du recrutement BAZ2B pour la réplication HDV, nous avons transfecté des lignées cellulaire Huh–7 exprimant de façon stable, soit la protéine sauvage S–HDAg ou le mutant R75A pour étudier la réplication HDV à partir plasmide pSVLD2m défectif pour l'expression de S–HDAg. Nos résultats indiquent que la synthèse de l'ARN génomique est fortement réduite dans les cellules exprimant le mutant R75A S–HDAg par rapport aux cellules exprimant le type sauvage S–HDAg, alors que la quantité d'ARN antigénomique est restée le même dans les deux cas. Des expériences de co–cristallisation et de siRNA sont actuellement menées afin de mieux caractériser au niveau moléculaire l'association entre BAZ2B BRD et des peptides dérivés de la séquence de S–HDAg et d'étudier les conséquences de l'inhibition par siRNA de BAZ2B. L'implication des BAZ2B dans la réplication de HDV pourra ouvrir des possibilités de développement de médicaments anti–HDV, basées sur l'optimisation des inhibiteurs émergents de BAZ2B–BRD / Hepatitis Delta Virus (HDV) is a satellite of Hepatitis B Virus (HBV), leading to more severe life threatening liver diseases than HBV mono–infection. No efficient therapy is available against HDV and the estimated 15 million HDV infected individuals worldwide are at a high risk of cirrhosis and hepatocellular carcinoma. HDV is a unique RNA virus as it does not encode a viral polymerase. HDV RNA replication occurs via a double rolling circle mechanism generating unit–length genomic or antigenomic RNA strands. The synthesis of the genomic RNA is sensitive to low concentrations of α–amanitin, suggesting that the RNA–dependent RNA synthesis is mediated by DNA–dependent RNA polymerase II (RNA Pol II). This process relies on the HDV encoded Small Hepatitis Delta antigen (S–HDAg), which must be acetylated at K72 to activate the synthesis of the genomic RNA. We recently identified BAZ2B (Bromodomain Associated to Zinc finger protein 2B) as a major interactant of S–HDAg by affinity capture coupled to mass spectrometry in differentiated HepaRG cells. The biological function of BAZ2B is however unknown. In comparison with related BAZ proteins (BAZ–1A/1B/2A), it is postulated that BAZ2B is the accessory subunit of a new chromatin remodeling complex of ISWI–type, which regulates nucleosome positioning through ATP hydrolysis. Recent studies revealed that the BAZ2B bromodomain (BRD) recognizes the distinct epigenetic signature K14ac–X–X–R on histone H3. This suggests that the mode of action of BAZ2B associated chromatin remodeling complex involves recognizing propagated specific histone acetylation marks to subsequently alter the chromatin dynamic and recruit the RNA Pol II for transcriptional activation. We hypothesized that the p300–mediated acetylation of the conserved K72–X–X–R motif in S–HDAg mimics acetylated histones on the pseudo–double stranded antigenomic RNA, to recruit the BAZ2B associated chromatin remodeling complex to initiate RNA Pol II mediated synthesis of HDV genome. To confirm the functional relevance of BAZ2B recruitment for HDV replication, we transfected Huh 7 cells stably expressing either wild–type S–HDAg or R75A mutant S–HDAg with the HDV replication defective plasmid pSVLD2m. Our results indicate that the synthesis of genomic RNA was greatly reduced in cells expressing the R75A mutant S–HDAg in comparison to cells expressing wild–type S–HDAg, whereas the amount of antigenomic RNA remained the same in both cases. Co–crystallization experiments are currently being carried out to better characterize at the molecular level the association between BAZ2B BRD and S–HDAg derived peptides. Furthermore, siRNA experiments directed against the BAZ2B gene are expected to reveal the consequences of BAZ2B inhibition on HDV viral replication. The involvement of BAZ2B in HDV replication may open anti–HDV drug development opportunities, based on the optimization of emerging BAZ2B–BRD inhibitors
353

Byron's Shakespearean Imitations

Barber, Benjamin January 2016 (has links)
Though Byron is known for his provocative denials of the importance of Shakespeare, his public derogations of the early modern playwright are in fact a pose that hides the respect he had for the playwright’s powerful poetic vision, a regard which is recorded most comprehensively in the Shakespearean references of Don Juan. Byron imitated Shakespeare by repeating and adapting the older poet’s observations on the imitative nature of desire and the structure of emulous ambition as a source of violence. His appropriations make his work part of the modern shift away from earlier European societies, wherein ritual means of mitigating desire’s potentially inimical impact on human communities were supplemented with an increased reliance on market mechanisms to defer the effects of emulation and resentment. Finding himself among the first modern celebrities, Byron deploys Shakespeare’s representations of desire to trace the processes that produced the arc of his own fame and notoriety. Drawing on his deep knowledge of Shakespeare, Byron’s poetic vision—in its observations on the contagious nature of desire—exhibits elements of Shakespeare’s own vivid depictions of imitation as a key conduit for his characters’ cupidity, ambitions, and violence. Exploring how he plays with and integrates these representations into his letters, journals, poetry, and plays, my dissertation investigates Byron’s intuitions on the nature of human desire by focusing on his engagement with one of literature’s greatest observers of human behaviour, Shakespeare.
354

Efficacité comparée de différentes formes de « modèles ajustés » pour l’acquisition de tâches gymniques : rôle des « Coping modèles » et de l’Imitation Modélisation Interactive / Comparing various adjusted forms of modeling : the role of « coping models » and “Interactive models” for the acquisition of gymnic skills

Martin, Liza 13 December 2011 (has links)
Ce travail de recherche examine les conditions d’efficacité de procédures ajustées de modélisation pour l’apprentissage d’habiletés gymniques, et en particulier des « coping models ». Il mesure les effets de différents types de démonstration sur le processus d’acquisition et les réponses psychologiques de débutantes en gymnastique. Le cadre théorique-support concerne la psychologie sociale du développement et des acquisitions. Notre démarche empirique convoque un contexte virtuel (première étude) et un contexte plus naturel et écologique, faisant intervenir des modèles vivants (les deuxième et troisième expérimentations). Les résultats mettent en évidence la supériorité des guidages ajustés, tant sur l’amélioration motrice que les états psychologiques conditionnant l’apprentissage. Les données recueillies à l’issue des trois expériences montrent que les « coping models » seraient particulièrement efficaces dans le cas où la tâche est anxiogène et acrobatique. Les modèles « Imitation Modélisation Interactive » offrent des bénéfices très intéressants dans les situations d’acquisition de tâches non-anxiogènes. De manière sous-jacente, les protocoles soulignent la nécessité et la pertinence de dispositifs de formation au modeling en contexte scolaire. / The aim of this study is to examine the effectiveness of various forms of modeling, and particularly coping models. This work assesses the effects of different types of demonstrations on the learning process and psychological responses. The theoretical framework is social psychology of development and learning. Our empirical intervention considers both a virtual context (1st study) and a context more ecological, using peer live models (2nd and 3rd studies). Results emphasize the superiority of adjusted and progressive demonstrations, both for motor learning and for psychological states influencing performance. Coping models show particular effectiveness when the task to be learned is stressful. Interactive models are really helpful for the gymnic skill towards which learners don’t feel anxious. Data collected also suggest the necessity and benefits of training programs for models.
355

The Role of Self-Efficacy and Modeling in Improvisation: The Effects of Aural and Aural/Notated Modeling Conditions on Intermediate Instrumental Music Students' Improvisation Achievement

Davison, Patrick Dru 12 1900 (has links)
The first purpose of this study was to investigate whether different modeling conditions (Aural and Aural/Notated Transcription) produced significant differences for improvisation achievement. Another purpose was to investigate whether music learning theory-based improvisation instruction had an effect on students' self-efficacy for improvisation and for instrumental music. Participants (N = 76) from an accessible population of 6th through 8th grade instrumental music students were assigned to either an aural model group or an aural and notated transcription model group based on scores from Gordon's Harmonic and Rhythmic Readiness Records (1998). All students were administered two researcher-designed self-efficacy scales before and after a 10 treatment session music learning theory-based improvisation instruction. Following the treatment sessions, each participant was individually recorded and assessed by three experienced music educators. The posttest improvisation scores were subjected to an ANOVA, while the pretest to posttest scores of the students' self-efficacies for music improvisation and instrumental music were subjected to two repeated measures ANOVAs. The Bonferroni technique was used to adjust the alpha level from .05 to .017. The statistical analysis showed that there was no significant difference in improvisation achievement for the modeling conditions of aural and aural/notated transcription. Further statistical analyses showed there were significant increases in students' self-efficacy for improvising and for instrumental music following improvisation instruction. This study's results suggest that music educators should consider using either modeling technique for improvisation learning experiences. Results also suggest that music educators may wish to consider using a music learning theory-based improvisation approach to facilitate greater confidence in improvising. Additionally, results suggest that classroom music educators may wish to consider improvisation instruction as a means for achieving greater student confidence in instrumental music. This study concludes with issues for further study.
356

Novel Learning-Based Task Schedulers for Domain-Specific SoCs

January 2020 (has links)
abstract: This Master’s thesis includes the design, integration on-chip, and evaluation of a set of imitation learning (IL)-based scheduling policies: deep neural network (DNN)and decision tree (DT). We first developed IL-based scheduling policies for heterogeneous systems-on-chips (SoCs). Then, we tested these policies using a system-level domain-specific system-on-chip simulation framework [11]. Finally, we transformed them into efficient code using a cloud engine [1] and implemented on a user-space emulation framework [61] on a Unix-based SoC. IL is one area of machine learning (ML) and a useful method to train artificial intelligence (AI) models by imitating the decisions of an expert or Oracle that knows the optimal solution. This thesis's primary focus is to adapt an ML model to work on-chip and optimize the resource allocation for a set of domain-specific wireless and radar systems applications. Evaluation results with four streaming applications from wireless communications and radar domains show how the proposed IL-based scheduler approximates an offline Oracle expert with more than 97% accuracy and 1.20× faster execution time. The models have been implemented as an add-on, making it easy to port to other SoCs. / Dissertation/Thesis / Masters Thesis Computer Engineering 2020
357

Towards optimal measurement and theoretical grounding of L2 English elicited imitation: Examining scales, (mis)fits, and prompt features from item response theory and random forest approaches

Ji-young Shin (11560495) 14 October 2021 (has links)
<p>The present dissertation investigated the impact of scales / scoring methods and prompt linguistic features on the meausrement quality of L2 English elicited imitation (EI). Scales / scoring methods are an important feature for the validity and reliabilty of L2 EI test, but less is known (Yan et al., 2016). Prompt linguistic features are also known to influence EI test quaity, particularly item difficulty, but item discrimination or corpus-based, fine-grained meausres have rarely been incorporated into examining the contribution of prompt linguistic features. The current study addressed the research needs, using item response theory (IRT) and random forest modeling.</p><p>Data consisted of 9,348 oral responses to forty-eight items, including EI prompts, item scores, and rater comments, which were collected from 779 examinees of an L2 English EI test at Purdue Universtiy. First, the study explored the current and alternative EI scales / scoring methods that measure grammatical / semantic accuracy, focusing on optimal IRT-based measurement qualities (RQ1 through RQ4 in Phase Ⅰ). Next, the project identified important prompt linguistic features that predict EI item difficulty and discrimination across different scales / scoring methods and proficiency, using multi-level modeling and random forest regression (RQ5 and RQ6 in Phase Ⅱ).</p><p>The main findings were (although not limited to): 1) collapsing exact repetition and paraphrase categories led to more optimal measurement (i.e., adequacy of item parameter values, category functioning, and model / item / person fit) (RQ1); there were fewer misfitting persons with lower proficiency and higher frequency of unexpected responses in the extreme categories (RQ2); the inconsistency of qualitatively distinguishing semantic errors and the wide range of grammatical accuracy in the minor error category contributed to misfit (RQ3); a quantity-based, 4-category ordinal scale outperformed quality-based or binary scales (RQ4); sentence length significantly explained item difficulty only, with small variance explained (RQ5); Corpus-based lexical measures and phrase-level syntactic complexity were important to predicting item difficulty, particularly for the higher ability level. The findings made implications for EI scale / item development in human and automatic scoring settings and L2 English proficiency development.</p>
358

Zařízení pro napodobení statických a dynamických vlastností písma / Device for Imitation of Static and Dynamic Handwriting Characteristics

Pawlus, Jan January 2019 (has links)
This project deals with designing and assembling a system for imitation of static and dynamic handwriting characteristics. This system's design takes into account special pen targeted for getting the handwriting characteristics, working with these characteristics and their imitation with a 3D printer altered for this purpose. This topic might be interesting because research about this specific field, which would include a real demonstration of how a signature can be forged using dynamic handwriting characteristics not by forger's hand, barely exists. The problem with preventing forgery is that we need to know the attack well, which is a clear motivation for this project.
359

Imitace ruského přízvuku českými mluvčími / Imitation of the Russian accent by Czech speakers

Nudga, Natalia January 2020 (has links)
(in English) Foreign accent imitation is one of the strategies used in intentional voice disguise. This thesis focuses on imitation of the Russian accent in Czech language by Czech speakers and describes the imitated accent based on auditory and acoustic analysis. Both segmental and suprasegmental features of speech have been analysed based on the comparison of audio recordings of regular speech and speech with imitated Russian accent. The most frequent difference implemented by Czech speakers during the imitation task involved the change of duration of vowels in relation to the position of word stress and included both lengthening of stressed vowels and shortening of unstressed ones. Change of vowel quality has been performed mostly on the vowel [ɪ], resulting in a close vowel [i] or resembling [ɨ]. Consonantal deviations usually concerned Czech sounds [ɦ] and [r̝ ], and palatalization of lateral consonant [l]. Audio recordings of Czech imitators as well as Russian speakers were used in the perception test, in which participants had to judge the authenticity of foreign accent. Four out of ten imitators were rated by the majority of listeners as genuine non-native speakers, whereas two out of five Russian speakers were misjudged for imitators. The accent of successful imitators was characterised by...
360

L'écriture juridique autochtone comme lieu de rencontre des cultures juridiques

Sabourin, Vicky 23 June 2022 (has links)
La recherche à l’origine de cette thèse avait comme objectifs de découvrir le rôle, les fonctions, les défis et les enjeux de l’écriture juridique autochtone en marge de l’État. La cueillette des données s’est effectuée par la lecture de documents scientifiques et par des entrevues de recherche collaborative avec certains Atikamekw Nehirowisiwok, des Pekuakamiulnuatsh et un chef coutumier Kanak, tous ayant participé à la rédaction de documents juridiques au sein de leur communauté. Conséquemment, les résultats de la recherche ont aussi fait surgir la relation qu’entretiennent le droit écrit et le droit non écrit. De plus, les données recueillies ont permis de mobiliser le cadre conceptuel de la gestion du pluralisme juridique qui a été défini un peu plus tard dans le travail de recherche et de faire ressortir les procédés qui sont le plus utilisés par les communautés autochtones étudiées. La présente recherche a permis de conclure que l’écrit est en fait un lieu de rencontre des cultures juridiques, et qu’ainsi, il a comme rôle commun la communication avec le système étatique, l’autodétermination et l’autonomie gouvernementale.

Page generated in 0.1077 seconds