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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.
201

Motor control of the knee : kinematic and EMG studies of healthy individuals and people with patellofemoral pain

Stensdotter, Ann-Katrin January 2005 (has links)
Patellofemoral pain (PFP) is believed to be associated with deficits in coordination between the different heads of the quadriceps muscle; however, considerable debate exists in the literature regarding the presence of such a deficit. Discrepancies between studies may be explained by differences in experimental tasks, such as whether the task is performed with open (OKC) or closed kinetic chain (CKC), or whether the activity is voluntary or triggered. Particular interest has been directed toward the function of the vastus medialis obliquus (VMO), which is a short muscle with limited ability to exert torque across the knee joint, but probably has a particular role in controlling patellofemoral joint position. Another short muscle that may influence knee joint position control is popliteus (POP), which is located in the back of the knee. This thesis investigates task specific activity of quadriceps in CKC versus OKC and studies the relative activity between the four heads of the quadriceps in PFP subjects compared to controls without knee pain in voluntary activity (CKC and OKC) and postural responses to balance perturbations. In addition, this thesis investigates the presumed function of POP for control of joint position in postural tasks in healthy individuals. All subjects were of normal weight and height and between 18 and 40 years. Quadriceps activity was tested for isometric with identical joint configuration in CKC and OKC, and it was performed as a reaction time task. Balance perturbations were elicited by unpredictable anterior and posterior translations of the support surface. Function of POP was investigated in unpredictable support surface translations and in self induced provocations to balance by moving the arms. Muscle activity was recorded with electromyography (EMG). Optic kinematic analysis was used to obtain specific movement responses to perturbations of balance. The quadriceps muscles were activated differently in CKC and OKC. VMO was activated earlier and to a greater degree in CKC. Rectus femoris was activated earlier and to a greater degree in OKC. PFP subjects reacted slower in both CKC and OKC, but there was no difference between groups in the relative activity between the different heads of the quadriceps. In the unpredictable support surface translation in the anterior direction, PFP subjects responded with earlier onset of VMO and with greater trunk and hip flexion in the anterior translation. POP activation in response to support surface translations in both directions occurred before all other muscles measured. In the self-initiated provocations of balance, POP was activated after the initiation of the balance provocation. This thesis concludes that quadriceps activity was task specific. The lack of difference between groups in OKC and CKC, and the difference between groups in postural responses suggest that variations in motor behaviour may occur only in tasks habitually performed. Differences in muscle activation patterns may be related to compensatory strategies to unload the quadriceps muscles and the patellofemoral joint. Furthermore, this thesis suggests that POP muscle may have a particular role in active control of the knee joint.
202

Rekonstruktion av logaritmer med tallinjer som medierande redskap / Reconstructing logarithms using number lines as mediated tools

Fermsjö, Roger January 2014 (has links)
The aim of the research reported in this licentiate thesis was to create an environment that could support students’ learning about logarithms. To develop such a learning environment, Davydov’s ‘learning activity’ was used as a theoretical framework for the design. A new tool was created, that was used by the students to unfold and single out some of the unique properties of logarithms when solving different learning tasks. The construction of the model was inspired by Napiers original idea from 1614, i.e. exactly 400 years ago, by using two number lines; one arithmetic (i.e. based on addition) and one geometric (i.e. based on multiplication). The research approach used was learning study where teachers and researcher worked collaboratively in an iterative process to refine the research lesson. The study was conducted in six groups with six teachers in upper secondary school in a major city in Sweden. The sample comprised about 150 students and data were collected by filming lessons and by interviews with some of the students. The data were analysed using an analytic framework derived from ‘learning activity’ and the results show what supports, but also what does not support, the creation of an environment for supporting students’ learning of logarithms. The results from the study are related to former research regarding instrumental/procedural vis-à-vis relational/conceptual understanding and also about research about students’ ‘errors and misconceptions’. It is argued that the formal definition of logarithms, y = 10x <-> x = lgy (y > 0), should not be used to introduce the concept, instead a new way is proposed. One conclusion is that it is possible to reconstruct logarithms without using the definition as a tool. The results from the analysed lessons show how students looked for ways to solve learning tasks using the new tool. The definition and the identities regarding logarithms appear as bi-products of the students learning activity. When analysing students actions, they rarely over-generalised mathematical rules, e.g. used the distributive law, or separated log-expressions, e.g. adding log expressions part by part, that seemed to be an issue according to former research.
203

Reminding and refinding: examining how software developers use annotations

Ryall, Jody 29 April 2008 (has links)
Software development requires understanding and navigating complex software spaces. Developers frequently utilize annotations in source code to help them externalize information they need to remember, such as tasks and implementation details. Although some tool support exists in modern integrated development environments for authoring and navigating these annotations, we have observed that they often fail to remind developers about tasks that need to be performed and are sometimes difficult to find. We present the results from four empirical studies designed to better understand how developers create and manage their information using annotations. We also explore the use of hierarchical tagging capabilities to enhance these annotations. Based on the findings from these studies, we provide suggestions on how annotation tools may be improved.
204

Communication Strategy Use in Performing Informal Debate Tasks by Chinese English-as-an-Additional-Language Graduate Students in Electrical Engineering and Education

Zhou, Ci-Hang 07 May 2014 (has links)
In the field of second language acquisition, there are few studies focusing on Chinese English-as-an-additional-language (EAL) graduate students’ communication strategy use, strategy use across different disciplines, and the relationships between communication strategy use and learners’ speaking performance. To fill the gap identified in the literature reviewed, this study examined the communication strategies used by 11 Chinese EAL graduate students from the Departments of Electrical Engineering and Education in the completion of two informal debate tasks with a questionnaire adapted from Nakatani’s (2006) Oral Communication Strategy Inventory and two post-task communication strategy recall questionnaires. Results from the study indicate that participants used eight categories of communication strategies, with fluency-oriented strategies the most frequently used strategy category and translation the least frequently used strategy category. Advanced English-language proficiency level learners used more social affective, message reduction and alteration, and negotiation of meaning strategies than learners at high-intermediate proficiency levels, to a degree that was statistically significant. No significant difference was identified in the overall communication strategy use but in one instance of individual strategy use (i.e., clarifying stance) across two disciplines. Significantly positive relationships were identified among certain categories of communication strategies (i.e., social affective, negotiation of meaning, accuracy-oriented strategies, and message reduction and alteration strategies), individual strategies (i.e., turn yielding, exemplifying, clarifying meaning, correcting others, referring to notes for accuracy/fluency, message reduction and alteration), and participants’ speaking performance. In addition, the retrospective results from the post-task strategy recall questionnaires suggest that participants in this study are not fully aware of their communication strategy use. The findings in this study can inform language practitioners’ of communication strategies used by Chinese graduate students majoring in Electrical Engineering and Education. Implications and future research directions are discussed in light of the findings derived from the present study that can further contribute to research about EAL learners’ communication strategies used at the graduate level. / Graduate / 0290 / cihangzh@uvic.ca
205

The Exploration of Critical Care Nurses' Use of Accumulated knowledge and Information-seeking for Non-routine Tasks

Newman, Kristine 18 December 2012 (has links)
Background Nurses complete tasks during patient care to promote the recovery, or to maintain the health, of patients. These tasks can be routine or non-routine to the nurse. Non-routine tasks are characterized by unfamiliarity, requiring nurses to seek additional information from a variety of sources to effectively complete the tasks. Nurses’ perception of their problem-solving skills, as characterized by the attributes of personal control, problem-solving confidence, and avoidance-approach style, influences how information is sought. Objectives/Research Questions Guided by the information-seeking behaviour model, this study was designed to: (1) examine how the non-routineness of the task affects nurses’ information-seeking behaviour and the use of accumulated knowledge; and, (2) explore nurses’ perception of their problem-solving abilities. Methods An exploratory cross-sectional survey design was used. A random sample of critical care nurses who worked in a hospital setting were selected from the College of Nurses of Ontario (CNO) research participant database. Multiple regression analysis was used to examine the proposed relationships. Results Avoidance-approach style and, problem-solving confidence did not have a significant relationship with nurses’ information-seeking behaviour. None of the variables explained use of accumulated knowledge (F = 0.902, p > 0.05). Previous training (p = 0.008), Non-routineness of the task (p = 0.018), and Personal control (p = 0.040) had a positive relationship with information-seeking behaviour (Adjusted R2 = 0.136). Implications The study results provide evidence that problem-solving ability, and in particular the attribute of personal control, influences nurses’ information-seeking behaviour during the completion of nursing tasks. They reveal how information is sought from resources, and what specific information resources are necessary to promote access to, and use of, evidence-based information. The results also help direct efforts towards training nurses in issues related to problem-solving and information-seeking by targeting the development of personal control and retrieving evidence-based information.
206

Modelling tasks for learning, teaching, testing and researching

Greefrath, Gilbert 16 April 2012 (has links) (PDF)
The article deals with a special kind of modelling tass. These problems are used for learning and researching as well. So the results of an empirical study on mathematical modelling of pupils in secondary schools are presented. Pupils of forms 8-10 were observed working on open, realistic problems. These observations were recorded and evaluated. The goal of the presented part of the study is a detailed look at the control processes of modelling problems. In this context changes between real life control and mathematical control during the control phases are studied and evaluated. We describe in detail the sub phases of controlling and explain their connection with modelling process. The problems used in this project can also be used in math lessons, so this kind of research can put teachers and researchers together. These tasks are suitable to support ongoing in-service development and teacher education.
207

Psychological and Family Characteristics of Adolescents with Type 2 Diabetes

Mireles, Gerardo 2012 August 1900 (has links)
Type 2 diabetes mellitus (T2DM) is now increasingly diagnosed in children and adolescents at an alarming rate, especially in youth from diverse ethnic backgrounds. Youth diagnosed with T2DM and their families face many challenges associated with the illness and its complications. Given that the prevalence of T2DM in youth is a recent trend, most of the studies examining T2DM have been conducted with adults. The current study expands the literature base of youth with T2DM by collecting demographic and clinical data of youth with T2DM and their families. Regression analyses were used to investigate the relationship among youth's executive function, their body mass index (BMI) and glycosylated hemoglobin (HbA1c) level. Furthermore, the study analyzed the relationship among depressive symptoms and health related quality of life (HRQOL) in youth, and the role of family members in sharing of tasks related to T2DM care and the youth's HRQOL. Results of this study demonstrated that executive function does not predict a youth's HbA1c, nor their BMI. Interestingly, one of the more significant findings to emerge from this study is that youth's rating of their ability to adjust to changes in routine or task demands and their ability to modulate emotions significantly correlated with their BMI. Results also demonstrated that HbA1c does not mediate the relationship between depressive symptoms and HRQOL, nor the relationship between the family sharing of responsibilities related to T2DM tasks and HRQOL. Future research examining the relationship among psychological and family characteristics can aid the development of diabetes prevention and treatment management.
208

Evaluating the utility of the adaptive tasks framework for assessing parental needs when providing primary care for their child with a chronic health condition

Sahraei, Valla 11 1900 (has links)
The purpose of this study was to evaluate the utility of the Adaptive Tasks Framework for assessing parental needs when providing primary care for their child with a chronic health condition. A qualitative descriptive methodology framed the study and two methods were employed to collect data: a secondary analysis of existing interview data from seven parents of children with chronic health conditions and interviews with four parents who were currently providing primary care for their child with a chronic health condition. The data was analyzed using content analysis, whereby interview data was explored to determine if it fit into one or more of the eight adaptive tasks categories. Parents reported needs in all of the eight adaptive tasks categories, with the need for information regarding their child's chronic health condition being the foremost concern among parents. The need for caring, empathetic, and patient health care professionals who are sympathetic to the informational needs of parents, while at the same time acknowledging their expertise, was the second need expressed by the parents in this study. Implications of these findings for nurses is that the Adaptive Tasks Framework provides a useful tool for assessing parental needs when managing their child's chronic health condition and for determining areas in which the parents may require support.
209

Robust incremental relational learning

Westendorp, James, Computer Science & Engineering, Faculty of Engineering, UNSW January 2009 (has links)
Real-world learning tasks present a range of issues for learning systems. Learning tasks can be complex and the training data noisy. When operating as part of a larger system, there may be limitations on available memory and computational resources. Learners may also be required to provide results from a stream. This thesis investigates the problem of incremental, relational learning from imperfect data with constrained time and memory resources. The learning process involves incremental update of a theory when an example is presented that contradicts the theory. Contradictions occur if there is an incorrect theory or noisy data. The learner cannot discriminate between the two possibilities, so both are considered and the better possibility used. Additionally, all changes to the theory must have support from multiple examples. These two principles allow learning from imperfect data. The Minimum Description Length principle is used for selection between possible worlds and determining appropriate levels of additional justification. A new encoding scheme allows the use of MDL within the framework of Inductive Logic Programming. Examples must be stored to provide additional justification for revisions without violating resource requirements. A new algorithm determines when to discard examples, minimising total usage while ensuring sufficient storage for justifications. Searching for revisions is the most computationally expensive part of the process, yet not all searches are successful. Another new algorithm uses a notion of theory stability as a guide to occasionally disallow entire searches to reduce overall time. The approach has been implemented as a learner called NILE. Empirical tests include two challenging domains where this type of learner acts as one component of a larger task. The first of these involves recognition of behavior activation conditions in another agent as part of an opponent modeling task. The second, more challenging task is learning to identify objects in visual images by recognising relationships between image features. These experiments highlight NILE'S strengths and limitations as well as providing new n domains for future work in ILP.
210

Effects of Caffeine on Cognitive Tasks

Valladares, Lorraine, lorraine.valladares@rmit.edu.au January 2009 (has links)
The effects of caffeine (250 mg) and placebo on healthy controls were studied in a double-blind, cross over study on 24 healthy subjects who performed a working memory n-back task. Reaction time and accuracy levels were tested using the n-back working memory measure in cognitive neuroscience. An experimental study tested on the 1, 2 and 3-back tasks under the placebo/coffee condition. Based on the empirical results obtained in this thesis it can be concluded that changes produced by caffeine ingestion support the hypothesis that caffeine acts as a stimulant. However, it cannot be proven that the stimulant translates into enhanced motor processes with an improvement in performance.

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