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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.
401

Relationships among Span, Time Allocation, and Leadership of First-line Managers and Nurse and Team Outcomes

Meyer, Raquel 31 August 2010 (has links)
Comparisons of raw span (i.e., number of staff who report directly to a manager) within and across organizations can misrepresent managerial capacity to support staff because managers may not allocate the same amount of time to staff contact. The purpose was to examine the influence of alternative measures of managerial span on nurse satisfaction with manager’s supervision and on multidisciplinary teamwork. The alternative measures were (a) raw span as a measure of reporting structure and (b) time in staff contact as a measure of closeness of contact by the manager. The main effects of the alternative measures, leadership, hours of operation, and other covariates on outcomes were examined. The interaction effects of the alternative measures with leadership and hours of operation were investigated. The study framework was based on Open System Theory and the boundary spanning functions of managers. A descriptive, correlational design was used to collect survey and administrative data from employees, managers, and organizations. Managerial time allocation data were collected through self-logging and validated through observation. Acute care hospitals were selected through purposive sampling. For supervision satisfaction, the final sample size was 31 first-line managers and 558 nurses. For teamwork, the final sample size was 30 first-line managers and 754 staff. The Leadership Practices Inventory, the Satisfaction with my Supervisor Scale, and the Relational Coordination Scale were used. Hierarchical linear modeling was the main type of analysis conducted. Raw span interacted with leadership and hours of operation to explain supervision satisfaction. Teamwork was explained by leadership, clinical support roles, hours of operation, total areas, and non-direct reports, but not by raw span or time in staff contact. Large acute care hospitals can improve satisfaction with supervision and teamwork by modifying first-line management positions.
402

Circuit Timing and Leakage Analysis in the Presence of Variability

Heloue, Khaled R. 15 February 2011 (has links)
Driven by the need for faster devices and higher transistor densities, technology trends have pushed transistor dimensions into the deep sub-micron regime. This continued scaling, however, has led to many challenges facing digital integrated circuits today. One important challenge is the increased variations in the underlying process and environmental parameters, and the significant impact of this variability on circuit timing and leakage power, making it increasingly difficult to design circuits that achieve a required specification. Given these challenges, there is a need for computer-aided design (CAD) techniques that can predict and analyze circuit performance (timing and leakage) accurately and efficiently in the presence of variability. This thesis presents new techniques for variation-aware timing and leakage analysis that address different aspects of the problem. First, on the timing front, a pre-placement statistical static timing analysis technique is presented. This technique can be applied at an early stage of design, when within-die correlations are still unknown. Next, a general parameterized static timing analysis framework is proposed, which supports a general class of nonlinear delay models and handles both random (process) parameters with arbitrary distributions and non-random (environmental) parameters. Following this, a parameterized static timing analysis technique is presented, which can capture circuit delay exactly at any point in the parameter space. This is enabled by identifying all potentially critical paths in the circuit through novel and efficient pruning algorithms that improve on the state of art both in theoretical complexity and runtime. Also on the timing front, a novel distance-based metric for robustness is proposed. This metric can be used to quantify the susceptibility of parameterized timing quantities to failure, thus enabling designers to fix the nodes with smallest robustness values in order to improve the overall design robustness. Finally, on the leakage front, a statistical technique for early-mode and late-mode leakage estimation is presented. The novelty lies in the random gate concept, which allows for efficient and accurate full-chip leakage estimation. In its simplest form, the leakage estimation reduces to finding the area under a scaled version of the within-die channel length auto-correlation function, which can be done in constant time.
403

Timing of Peak Mandibular Growth in Different Facial Growth Patterns and Resultant Mandibular Projection

Lee, Bennet 07 January 2011 (has links)
Objective: To determine if significant differences exist in timings and rates of Peak Mandibular Growth (PMG) and mandibular projections of subjects with vertical, average and horizontal facial growth patterns. Methods: Sixty-three Caucasian orthognathic subjects with cephalograms (9 to 18 years) available from the Burlington Growth Centre were categorized into average, vertical and horizontal growth pattern groups based on their change in Y axis from age 10 to 16 years. PMG timing and rates were determined and mandibular projections measured. Comparisons were made by ANOVA. Results: Inter-group differences of PMG timing or rate were not statistically significant. Although not statistically significant, PMG of vertically growing females was 14 month earlier than all other subgroups. Horizontal mandibular projection differences approached significance in older children. Conclusions: No statistically significant differences were found in the timing or rate of PMG in different facial growth patterns. Differences in horizontal mandibular projections approached significance with growth.
404

Fractal Dynamics of Circle Drawing in Children with ASD

Fleury, Amanda 07 December 2011 (has links)
Sensory motor deficits, although not part of the diagnostic criteria, are frequently reported in autism spectrum disorder (ASD). The ob jective of this project is to study the temporal and spatial dynamics of an approximately periodic motor activity (circle drawing) in children with ASD. The natural rhythm of periodic motor activities such as circle drawing are known to exhibit statistical persistence in typically developing individuals. A sample of 15 children aged 4 to 8 years, with a primary diagnosis of ASD were asked to draw circles using a computerized tablet and pen, which record spatio-temporal data. Results were compared with those of 19 typically developing children. While no differences were seen in statistical persistence, differences were observed in timing of discontinuous circle drawing and in kinetic process variable such as grip and axial forces. Understanding the specific nature of graphomotor deficits is the first step towards developing targeted treatment for these impairments.
405

Effect of Channel Stochasticity on Spike Timing Dependent Plasticity

Talasila, Harshit Sam 20 December 2011 (has links)
The variability of the postsynaptic response following a presynaptic action potential arises from: i) the neurotransmitter release being probabilistic and ii) channels in the postsynaptic cell involved in the response to neurotransmitter release, having stochastic properties. Spike timing dependent plasticity (STDP) is a form of plasticity that exhibits LTP or LTD depending on the precise order and timing of the firing of the synaptic cells. STDP plays a role in fundamental tasks such as learning and memory, thus understanding and characterizing the effect variability in synaptic transmission has on STDP is essential. To that end a model incorporating both forms of variability was constructed. It was shown that ion channel stochasticity increased the magnitude of maximal potentiation, increased the window of potentiation and severely reduced the post-LTP associated LTD in the STDP curves. The variability due to short term plasticity decreased the magnitude of maximal potentiation.
406

Timing of Peak Mandibular Growth in Different Facial Growth Patterns and Resultant Mandibular Projection

Lee, Bennet 07 January 2011 (has links)
Objective: To determine if significant differences exist in timings and rates of Peak Mandibular Growth (PMG) and mandibular projections of subjects with vertical, average and horizontal facial growth patterns. Methods: Sixty-three Caucasian orthognathic subjects with cephalograms (9 to 18 years) available from the Burlington Growth Centre were categorized into average, vertical and horizontal growth pattern groups based on their change in Y axis from age 10 to 16 years. PMG timing and rates were determined and mandibular projections measured. Comparisons were made by ANOVA. Results: Inter-group differences of PMG timing or rate were not statistically significant. Although not statistically significant, PMG of vertically growing females was 14 month earlier than all other subgroups. Horizontal mandibular projection differences approached significance in older children. Conclusions: No statistically significant differences were found in the timing or rate of PMG in different facial growth patterns. Differences in horizontal mandibular projections approached significance with growth.
407

Fractal Dynamics of Circle Drawing in Children with ASD

Fleury, Amanda 07 December 2011 (has links)
Sensory motor deficits, although not part of the diagnostic criteria, are frequently reported in autism spectrum disorder (ASD). The ob jective of this project is to study the temporal and spatial dynamics of an approximately periodic motor activity (circle drawing) in children with ASD. The natural rhythm of periodic motor activities such as circle drawing are known to exhibit statistical persistence in typically developing individuals. A sample of 15 children aged 4 to 8 years, with a primary diagnosis of ASD were asked to draw circles using a computerized tablet and pen, which record spatio-temporal data. Results were compared with those of 19 typically developing children. While no differences were seen in statistical persistence, differences were observed in timing of discontinuous circle drawing and in kinetic process variable such as grip and axial forces. Understanding the specific nature of graphomotor deficits is the first step towards developing targeted treatment for these impairments.
408

Effect of Channel Stochasticity on Spike Timing Dependent Plasticity

Talasila, Harshit Sam 20 December 2011 (has links)
The variability of the postsynaptic response following a presynaptic action potential arises from: i) the neurotransmitter release being probabilistic and ii) channels in the postsynaptic cell involved in the response to neurotransmitter release, having stochastic properties. Spike timing dependent plasticity (STDP) is a form of plasticity that exhibits LTP or LTD depending on the precise order and timing of the firing of the synaptic cells. STDP plays a role in fundamental tasks such as learning and memory, thus understanding and characterizing the effect variability in synaptic transmission has on STDP is essential. To that end a model incorporating both forms of variability was constructed. It was shown that ion channel stochasticity increased the magnitude of maximal potentiation, increased the window of potentiation and severely reduced the post-LTP associated LTD in the STDP curves. The variability due to short term plasticity decreased the magnitude of maximal potentiation.
409

Relationships among Span, Time Allocation, and Leadership of First-line Managers and Nurse and Team Outcomes

Meyer, Raquel 31 August 2010 (has links)
Comparisons of raw span (i.e., number of staff who report directly to a manager) within and across organizations can misrepresent managerial capacity to support staff because managers may not allocate the same amount of time to staff contact. The purpose was to examine the influence of alternative measures of managerial span on nurse satisfaction with manager’s supervision and on multidisciplinary teamwork. The alternative measures were (a) raw span as a measure of reporting structure and (b) time in staff contact as a measure of closeness of contact by the manager. The main effects of the alternative measures, leadership, hours of operation, and other covariates on outcomes were examined. The interaction effects of the alternative measures with leadership and hours of operation were investigated. The study framework was based on Open System Theory and the boundary spanning functions of managers. A descriptive, correlational design was used to collect survey and administrative data from employees, managers, and organizations. Managerial time allocation data were collected through self-logging and validated through observation. Acute care hospitals were selected through purposive sampling. For supervision satisfaction, the final sample size was 31 first-line managers and 558 nurses. For teamwork, the final sample size was 30 first-line managers and 754 staff. The Leadership Practices Inventory, the Satisfaction with my Supervisor Scale, and the Relational Coordination Scale were used. Hierarchical linear modeling was the main type of analysis conducted. Raw span interacted with leadership and hours of operation to explain supervision satisfaction. Teamwork was explained by leadership, clinical support roles, hours of operation, total areas, and non-direct reports, but not by raw span or time in staff contact. Large acute care hospitals can improve satisfaction with supervision and teamwork by modifying first-line management positions.
410

Circuit Timing and Leakage Analysis in the Presence of Variability

Heloue, Khaled R. 15 February 2011 (has links)
Driven by the need for faster devices and higher transistor densities, technology trends have pushed transistor dimensions into the deep sub-micron regime. This continued scaling, however, has led to many challenges facing digital integrated circuits today. One important challenge is the increased variations in the underlying process and environmental parameters, and the significant impact of this variability on circuit timing and leakage power, making it increasingly difficult to design circuits that achieve a required specification. Given these challenges, there is a need for computer-aided design (CAD) techniques that can predict and analyze circuit performance (timing and leakage) accurately and efficiently in the presence of variability. This thesis presents new techniques for variation-aware timing and leakage analysis that address different aspects of the problem. First, on the timing front, a pre-placement statistical static timing analysis technique is presented. This technique can be applied at an early stage of design, when within-die correlations are still unknown. Next, a general parameterized static timing analysis framework is proposed, which supports a general class of nonlinear delay models and handles both random (process) parameters with arbitrary distributions and non-random (environmental) parameters. Following this, a parameterized static timing analysis technique is presented, which can capture circuit delay exactly at any point in the parameter space. This is enabled by identifying all potentially critical paths in the circuit through novel and efficient pruning algorithms that improve on the state of art both in theoretical complexity and runtime. Also on the timing front, a novel distance-based metric for robustness is proposed. This metric can be used to quantify the susceptibility of parameterized timing quantities to failure, thus enabling designers to fix the nodes with smallest robustness values in order to improve the overall design robustness. Finally, on the leakage front, a statistical technique for early-mode and late-mode leakage estimation is presented. The novelty lies in the random gate concept, which allows for efficient and accurate full-chip leakage estimation. In its simplest form, the leakage estimation reduces to finding the area under a scaled version of the within-die channel length auto-correlation function, which can be done in constant time.

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