Modular and Reconfigurable Robots (MRRs) are those designed to address the increasing demand for flexible and versatile manipulators in manufacturing facilities. The term, modularity, indicates that they are constructed by using a limited number of interchangeable standardized modules which can be assembled in different kinematic configurations. Thereby, a wide variety of specialized robots can be built from a set of standard components. The term, reconfigurability, implies that the robots can be disassembled and rearranged to accommodate different products or tasks rather than being replaced. A set of MRR modules may consist of joints, links, and end-effectors. Different kinematic configurations are achieved by using different joint, link, and end-effector modules and by changing their relative orientation. The number of distinct kinematic configurations, attainable by a set of modules, varies with respect to the size of the module set from several tens to several thousands. Although determining the most suitable configuration for a specific task from a predefined set of modules is a highly nonlinear optimization problem in a hybrid continuous and discrete search space, a solution to this problem is crucial to effectively utilize MRRs in manufacturing facilities. The objective of this thesis is to develop novel optimization methods that can effectively search the Kinematic Configuration (KC) space to identify the most suitable manipulator for any given task. In specific terms, the goal is to develop and synthesize fast and efficient algorithms for a Task-Based Configuration Optimization (TBCO) from a given set of constraints and optimization criteria. To achieve such efficiency, a TBCO solver, based on Memetic Algorithms (MA), is proposed. MAs are hybrids of Genetic Algorithms (GAs) and local search algorithms. MAs benefit from the exploration abilities of GAs and the exploitation abilities of local search methods simultaneously. Consequently, MAs can significantly enhance the search efficiency of a wide range of optimization problems, including the TBCO. To achieve more optimal solutions, the proposed TBCO utilizes all the solutions of the Inverse Kinematics(IK) problem. Another objective is to develop a method for incorporating the multiple solutions of the IK problem in a trajectory optimization framework. The output of the proposed trajectory optimization method consists of a sequence of desired tasks and a single IK solution to reach each task point. Moreover, the total cost of the optimized trajectory is utilized in the TBCO as a performance measure, providing a means to identify kinematic configurations with more efficient optimized trajectories. The final objective is to develop novel IK solvers which are both general and complete. Generality means that the solvers are applicable to all the kinematic configurations which can be assembled from the available module inventory. Completeness entails the algorithm can obtain all the possible IK solutions.

Modular and Reconfigurable Robots (MRRs) are those designed to address the increasing demand for flexible and versatile manipulators in manufacturing facilities. The term, modularity, indicates that they are constructed by using a limited number of interchangeable standardized modules which can be assembled in different kinematic configurations. Thereby, a wide variety of specialized robots can be built from a set of standard components. The term, reconfigurability, implies that the robots can be disassembled and rearranged to accommodate different products or tasks rather than being replaced. A set of MRR modules may consist of joints, links, and end-effectors. Different kinematic configurations are achieved by using different joint, link, and end-effector modules and by changing their relative orientation. The number of distinct kinematic configurations, attainable by a set of modules, varies with respect to the size of the module set from several tens to several thousands. Although determining the most suitable configuration for a specific task from a predefined set of modules is a highly nonlinear optimization problem in a hybrid continuous and discrete search space, a solution to this problem is crucial to effectively utilize MRRs in manufacturing facilities. The objective of this thesis is to develop novel optimization methods that can effectively search the Kinematic Configuration (KC) space to identify the most suitable manipulator for any given task. In specific terms, the goal is to develop and synthesize fast and efficient algorithms for a Task-Based Configuration Optimization (TBCO) from a given set of constraints and optimization criteria. To achieve such efficiency, a TBCO solver, based on Memetic Algorithms (MA), is proposed. MAs are hybrids of Genetic Algorithms (GAs) and local search algorithms. MAs benefit from the exploration abilities of GAs and the exploitation abilities of local search methods simultaneously. Consequently, MAs can significantly enhance the search efficiency of a wide range of optimization problems, including the TBCO. To achieve more optimal solutions, the proposed TBCO utilizes all the solutions of the Inverse Kinematics(IK) problem. Another objective is to develop a method for incorporating the multiple solutions of the IK problem in a trajectory optimization framework. The output of the proposed trajectory optimization method consists of a sequence of desired tasks and a single IK solution to reach each task point. Moreover, the total cost of the optimized trajectory is utilized in the TBCO as a performance measure, providing a means to identify kinematic configurations with more efficient optimized trajectories. The final objective is to develop novel IK solvers which are both general and complete. Generality means that the solvers are applicable to all the kinematic configurations which can be assembled from the available module inventory. Completeness entails the algorithm can obtain all the possible IK solutions.

3D virtual worlds are emerging distance education technologies that offer collaborative learning environments and provide effective ways to apply task-based activities. The aim of this case study was to examine the contribution of task-based language learning in 3D virtual worlds to speak English as a foreign language among university preparatory class students in terms of anxiety, motivation, and self-confidence. Therefore, different English speaking practice tasks/activities were designed in Second Life. Participants had different roles based on the determined tasks and had speaking experiences with native speakers, friends, and instructors of METU preparatory school. Fifteen upper-intermediate level preparatory class students in the Department of Basic English at Middle East Technical University participated in the study which comprised a four week time span in May 2011. Data of the study included the qualitative data, gathered from the interviews. Those interviews were administered after the study to understand the effectiveness of task-based language learning in Second Life for students&#039 / anxiety, motivation, and self-confidence towards speaking English. According to the results, this study revealed important findings for language education field. The results of this study demonstrated the effectiveness of task-based language learning in Second Life environment which had positive impact on students. In this respect, it is suggested that the Second Life experience provided students to gain motivation and self-confidence and overcome their anxiety related problems towards speaking English. Therefore, this study may offer an insight for further studies to investigate the effectiveness of 3D virtual environments in language education, especially in Turkey.

This thesis describes an environment to evaluate and compare static schedulers for real pipelined streaming applications on massively parallel architectures, such as Intel Single chip Cloud Computer (SCC), Adapteva Epiphany, and Tilera TILE-Gx series. The framework allows performance comparison of schedulers in their execution time, or the energy usage of static schedules with energy models and measurements on real platform. This thesis focuses on the implementation of a framework evaluating the energy consumption of such streaming applications on the SCC. The framework can run streaming applications, built as task collections, with static schedules including dynamic frequency scaling. Streams are handled by the framework with FIFO buffers, connected between tasks. We evaluate the framework by considering a pipelined mergesort implementation with different static schedules. The runtime is compared with the runtime of a previously published task based optimized mergesort implementation. The results show how much overhead the framework adds on to the streaming application. As a demonstration of the energy measuring capabilities, we schedule and analyze a Fast Fourier Transform application, and discuss the results. Future work may include quantitative comparative studies of a range of different static schedulers. This has, to our knowledge, not been done previously.

Computer simulations are an indispensable tool for scientists to gain new insights about nature. Simulations of natural phenomena are usually large, and limited by the available computer resources. By using the computer resources more efficiently, larger and more detailed simulations can be performed, and more information can be extracted to help advance human knowledge. The topic of this thesis is how to make best use of modern computers for scientific computations. The challenge here is the high level of parallelism that is required to fully utilize the multicore processors in these systems. Starting from the basics, the primitives for synchronizing between threads are investigated. Hardware transactional memory is a new construct for this, which is evaluated for a new use of importance for scientific software: atomic updates of floating point values. The evaluation includes experiments on real hardware and comparisons against standard methods. Higher level programming models for shared memory parallelism are then considered. The state of the art for efficient use of multicore systems is dynamically scheduled task-based systems, where tasks can depend on data. In such systems, the software is divided up into many small tasks that are scheduled asynchronously according to their data dependencies. This enables a high level of parallelism, and avoids global barriers. A new system for managing task dependencies is developed in this thesis, based on data versioning. The system is implemented as a reusable software library, and shown to be as efficient or more efficient than other shared-memory task-based systems in experimental comparisons. The developed runtime system is then extended to distributed memory machines, and used for implementing a parallel version of a software for global climate simulations. By running the optimized and parallelized version on eight servers, an equally sized problem can be solved over 100 times faster than in the original sequential version. The parallel version also allowed significantly larger problems to be solved, previously unreachable due to memory constraints. / UPMARC / eSSENCE

Despite 21st Century technology, our nation’s high schools deliver a print-centric curriculum driven by high-stakes tests. A majority of states have adopted Common Core State Standards that incorporate producing and consuming multiple media texts. Some teachers have begun to include multimodal activities but few are exploiting the affordances of multimodal composition specifically for the benefit of English learners. Public high school teachers hold deficit views of English learners and fail to offer them challenging, creative tasks. Framed by the complementary sociocultural theories of ecological linguistics (van Lier, 2004), multimodality (Kress, 2010), and identity (Gee, 2001; Norton, 2000), this qualitative case study examined the process and product of high school English learners composing multimodally with digital video. Four questions guided the study: 1) What can we learn from adolescent English learners engaged in composing with video? 2) What identities do adolescent ELs explore while engaging in multimodal communication? 3) What processes do ELs engage in as they compose multimodally? 4) How do their multimodal compositions contribute to our understanding of ELs? Participants were enrolled in an elective English to Speakers of Other Languages (ESOL) class at a public high school during Spring semester of 2012. Data included student generated lesson artifacts, audio/video recordings, researcher journal, and participants' video compositions. Data were analyzed through an ongoing, recursive cycle to determine themes, categories, and trends. Visual and video data were examined through visual discourse analysis (Albers, 2007b; Kress & van Leeuwen, 2006) and multimodal interaction analysis (Norris, 2004). Addressing the process and product of learning to read and compose visual and video texts, this dissertation examines 3 pairs of student participants and their video compositions. It reveals English learners working collaboratively and creatively, exploring imagined identities, showing investment in learning, engaging in critical analysis, and effectively communicating through multiple modes. Multimodal analysis of three student videos revealed four patterns of multimodal design; less is less, layered modes, less is more, and overlapping modes. The study redefines English learners as multilingual, multimodal communicators. It illustrates the complexity and reveals the benefit of incorporating multimodal activities and provides a model for fostering multilingual, multimodal communicators.

In X-Ray CT, there is always a desire to maintain the image quality while reducing the radiation dose. Recently several dose reduction approaches in both software and hardware have been developed to achieve the goal of making radiation as low as possible. Thus, the assessment of image quality becomes an important factor for routine quality control of medical X-Ray devices. In this work, task-based image quality measurements using model observers were used to evaluate the performance of X-Ray CT systems. To evaluate the dose reduction ability, detection tasks as well as combined detection and estimation tasks were considered. In detection tasks and combined detection and estimation tasks, the channelized Hotelling observer (CHO) and channelized scanning linear observer (CSLO) (with Dense Difference of Gauss channels) were employed respectively. They were used to evaluate the dose reduction capability of the iterative reconstruction algorithm developed by GE compared to the traditional reconstruction algorithm, filtered backprojection (FBP). Additionally, CHO and CSLO were also used for optimization of CT protocols. Our methods were also applied to Cardiac CT systems for temporal resolution evaluations. Two reconstruction algorithms, FBP and the motion correction algorithm, Snapshot Freeze (SSF), operated at two heart-beating rates with two reconstruction windows were quantitatively evaluated using task-based measurements. Finally, due to the huge demand of data acquisitions in the conventional channelized model observers, a proposed High-Dose-Signal-LOOL CHO/CSLO (HL-CHO/CSLO) that could efficiently reduce the data requirement has also been investigated in the pure detection, and combined detection and estimation task. In all studies, the practicality and the use of real data is emphasized. The results of all these studies demonstrate the usefulness of the task-based measurements of image quality in X-Ray CT imaging.

In recent decades, the conceptualisation of translation competence and its development has attracted significant attention from translation researchers. Existing literature on translation competence is characterised by the prevalence of multi-componential models of translation competence, with inadequate attention paid to the interplay between competence components in the translation process. Therefore, this doctoral research sets out to re-conceptualise translation competence from a problem-solving perspective so as to understand translation competence and its development in the translation process. By re-defining and re-modelling translation competence with inspiration from problem-solving studies, this research proposes a conceptualisation of translation competence and its development that accommodates the translation process and the learning process. In order to validate the relevance of the proposed theoretical framework, a longitudinal study was conducted among a small group of Chinese students from an MA translation programme, using the translation task-based interview as the main research instrument. Findings from the empirical study have demonstrated the relevance and strength of the theoretical framework as well as revealing individual and shared paths of translation competence development among the learners. This research enriches the current understanding of translation competence and its development. It introduces a fresh perspective for conceptualising translation competence, proposes an effective instrument for empirical competence research, and identifies possible directions for further research. It also has practical implications for translation pedagogy, offering theoretical and empirical support for some recent approaches and trends in translator education and training.

This research is a practitioner inquiry into change in concepts in contexts of task based discourse in teacher education classrooms. The particular concepts selected for study are epistemic beliefs about knowledge in history. A hypothesis that there is a relationship between a perception of agency in task based discourse and change in concepts is proposed for research on the basis of a review of Kuhn's arguments for paradigm change and those of others on the problems of convergence of meaning between paradigms.1 Four of five quasi experimental studies conducted find tentative support for the alternative hypothesis and demonstrate how the relationship could be tested in the field. Change in epistemic beliefs from pre-test to post-test is significant in both groups, Control and Experimental, and consistently more and better change with moderate effect sizes is seen in the Experimental groups. A matched pedagogical method, experience of a range of suitable examples, Skemp (1971) was provided to both Control and Experimental groups and this is found to be effective in developing beliefs. The experimental construct, a perception of agency in task based discourse was enhanced in Experimental groups alone, which is used to explain the difference in change. A rubric, the Categories of Beliefs about Knowledge in History, CBKH, is developed and employed to examine responses to open ended questions. Likert Scales are also used and conclusions are drawn with a final quantitative analysis of data. Excerpts from a focus group discussion illustrate the process.

TAVARES, Maria da Glória Guará. Pre-task planning, working memory capacity, and L2 speech performance. 2008. 236f. Tese (Doutorado) - Universidade Federal de Santa Catarina, Pós-graduação em Letras/inglês e Literatura Correspondente, Florianópolis, 2008. / Submitted by anizia almeida (aniziaalmeida80@gmail.com) on 2016-09-09T11:59:33Z No. of bitstreams: 1 2008_tese_mggtavares.pdf: 1165475 bytes, checksum: 852a777e4cdd48f0e8e4a4c30db7d5c4 (MD5) / Approved for entry into archive by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2016-09-13T16:57:35Z (GMT) No. of bitstreams: 1 2008_tese_mggtavares.pdf: 1165475 bytes, checksum: 852a777e4cdd48f0e8e4a4c30db7d5c4 (MD5) / Made available in DSpace on 2016-09-13T16:57:35Z (GMT). No. of bitstreams: 1 2008_tese_mggtavares.pdf: 1165475 bytes, checksum: 852a777e4cdd48f0e8e4a4c30db7d5c4 (MD5) Previous issue date: 2008 / Research on task-based planning provides evidence of trade-off effects among the goals of fluency, accuracy, and complexity of L2 performance in the context of learners’ limited attentional resources (e.g., Foster & Skehan, 1996; Menhert, 1998; Yuan & Ellis, 2003). However, there is a lack of empirical investigation on the role of working memory within the effects of planning on L2 performance. The present study investigates the relationship among pre-task planning, working memory capacity, and L2 speech performance. More specifically, it addresses the question whether individual differences in working memory capacity plays a role in performance under planning conditions and in the processes learners engage in when they plan. A population of 50 students from Letras Licenciatura, Letras Secretariado, and Cursos Extracurriculares at Universidade Federal de Santa Catarina was divided in two groups: control and experimental. Participants in the control group performed a working memory test, two narrative tasks under a no-planning condition, and a retrospective interview. Participants in the experimental group performed a working memory test, two narrative tasks (one under a no-planning and one under a planning condition), a retrospective online protocol, and a retrospective interview. L2 speech performance was assessed in terms of fluency, accuracy, and complexity. In general, results show that under a no-planning condition, working memory capacity significantly correlates with L2 speech accuracy (for the control group) and L2 speech fluency (for the experimental group). Under a planning condition, working memory capacity significantly correlates with L2 speech fluency and complexity. As for the impact of planning on performance, there was a significant effect on L2 speech accuracy and complexity, but not on fluency. Results also show that learners engage mainly in organization of ideas, rehearsal, lexical searches, and monitoring when they plan an oral task. Moreover, higher spans employ significantly more metacognitive strategies during planning when compared to lower spans. Results were discussed in terms of the working memory capacity model proposed by Engle, Kane, and Tuholski (1999), according to which individuals differ in the capacity for controlled attention in face of interference; and studies on task-based planning (e.g.,Ortega, 1999, 2005; Foster & Skehan, 1996; Menhert, 1998; Yuan & Ellis, 2003). Pedagogical implications were also pointed out suggesting that planning is as a task implementation condition that can be employed in the L2 classroom with the aim of drawing learners’ attention to form. / As pesquisas sobre o planejamento dentro da abordagem de ensino baseado em tarefas evidenciam efeitos de troca atencional entre os aspectos da fluência, acurácia e complexidade do desempenho em L2 devido à limitação dos recursos atencionais dos aprendizes (Foster & Skehan, 1996; Menhert, 1998; Yuan & Ellis, 2003). Entretanto, há uma carência de investigação empírica sobre o papel da memória de trabalho mediante os efeitos do planejamento no desempenho oral em L2. O presente estudo investiga a relação entre planejamento pré tarefa, capacidade da memória de trabalho e desempenho oral em L2. Mais especificamente, ele investiga se diferenças individuais na capacidade de memória de trabalho afetam tanto o desempenho oral em condições de planejamento quanto os processos nos quais os aprendizes embarcam quando planejam uma tarefa oral. Uma população de 50 alunos dos cursos de Letras Licenciatura, Letras Secretariado e Cursos Extracurriculares foi dividida em dois grupos: controle e experimental. Participantes do grupo controle foram submetidos à coleta de dados que consistiu de: um teste de memória de trabalho, duas tarefas narrativas sob a condição de não planejamento e uma entrevista retrospectiva. Participantes do grupo experimental foram submetidos à coleta de dados que consistiu de um teste de memória de trabalho, duas tarefas narrativas (uma na condição de não planejamento e outra na condição de planejamento), um protocolo verbal e uma entrevista retrospectiva. O desempenho oral foi medido através da fluência, acurácia e complexidade. Em geral, os resultados mostram que na condição de não planejamento, há correlação significativa entre capacidade de memória de trabalho e fluência (para o grupo experimental), assim como também, entre capacidade de memória de trabalho e acurácia (para o grupo controle). Na condição de planejamento, há correlação significativa da capacidade de memória de trabalho com fluência e complexidade. Os resultados mostram também que o planejamento levou a diferenças significativas em acurácia e complexidade e que os alunos focam principalmente em organização de idEias, buscas lexicais, ensaio e monitoramento quando planejam uma tarefa oral em L2. Os resultados indicam ainda que o número de estratégias metacognitivas utilizadas durante o planejamento é significativamente maior para participantes com maior capacidade de memória de trabalho. Os resultados foram discutidos com base no modelo de memória de trabalho proposto por Engle, Kane e Tuholski (1999), segundo o qual, indivíduos se diferenciam em termos da capacidade de controle da atenção em condições de interferência; e também com base nos estudos sobre planejamento pré tarefa (Ortega, 1999, 2005; Foster & Skehan, 1996; Menhert, 1998; Yuan & Ellis, 2003). Implicações pedagógicas também foram apontadas sugerindo que o planejamento é uma condição de implementação de tarefas a qual pode ser adotada em sala de aula com o objetivo de chamar a atenção dos aprendizes para o foco na forma.