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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.
291

The Empirical Testing of Musical Performance Assessment Paradigm

Russell, Brian Eugene 03 May 2010 (has links)
The purpose of this study was to test a hypothesized model of aurally perceived performer-controlled musical factors that influence assessments of performance quality. Previous research studies on musical performance constructs, musical achievement, musical expression, and scale construction were examined to identify the factors that influence assessments of performance quality. A total of eight factors were identified: tone, intonation, rhythmic accuracy, articulation, tempo, dynamics, timbre, and interpretation. These factors were categorized as either technique or musical expression factors. Items representing these eight variables were chosen from previous research on scale development. Additional items, along with researcher created items, were also chosen to represent the variables of technique, musical expression and overall perceptions of performance quality. The 44 selected items were placed on the Aural Musical Performance Quality (AMPQ) measure and paired with a four-point Likert scale. The reliability for the AMPQ measure was reported at .977. A total of 58 volunteer adjudicators were recruited to evaluate four recordings that represented one of each instrumental category of interest: brass, woodwind, voice, and string. The resulting performance evaluations (N = 232) were analyzed using statistical regression and path analysis techniques. The results of the analysis provide empirical support for the existence of the model of aurally perceived performer-controlled musical factors. Technique demonstrated significant direct effects on overall perceptions of performance quality and musical expression. Musical expression also demonstrated a significant direct effect on overall perceptions of performance quality. The results of this study are consistent with hypothesized model of performer-controlled musical factors.
292

Creation and maintenance of a communication tree in wireless sensor networks

Jung, Eun Jae 10 October 2008 (has links)
A local reconfiguration algorithm (INP) for reliable routing in wireless sensor networks that consist of many static (fixed) energy-constrained nodes is introduced in the dissertation. For routing around crash fault nodes, a communication tree structure connecting sensor nodes to the base station (sink or root) is dynamically reconfigured during information dissemination. Unlike other location based routing approaches, INP does not take any support from a high costing system that gives position information such as GPS. For reconfigurations, INP uses only local relational information in the tree structure among nearby nodes by collaboration between the nodes that does not need global maintenance, so that INP is energy efficient and it scales to large sensor networks. The performance of the algorithm is compared to the single path with repair routing scheme (SWR) that uses a global metric and the modified GRAdient broadcast scheme (GRAB-F) that uses interleaving multiple paths by computation and by simulations. The comparisons demonstrate that using local relative information is mostly enough for reconfigurations, and it consumes less energy and mostly better delivery rates than other algorithms especially in dense environments. For the control observer to know the network health status, two new diagnosis algorithms (Repre and Local) that deal with crash faults for wireless sensor networks are also introduced in the dissertation. The control observer knows not only the static faults found by periodic testing but also the dynamic faults found by a path reconfiguration algorithm like INP that is invoked from evidence during information dissemination. With based on this information, the control observer properly treats the network without lateness. Local algorithm is introduced for providing scalability to reduce communication energy consumption when the network size grows. The performance of these algorithms is computationally compared with other crash faults identification algorithm (WSNDiag). The comparisons demonstrate that maintaining the communication tree with local reconfigurations in Repre and Local needs less energy than making a tree per each diagnosis procedure in WSNDiag. They also demonstrate that providing scalability in Local needs less energy than other approaches.
293

The Effects of Handwriting, Spelling, and T-Units on Holistic Scoring with Implications for Dysgraphia

Hooten, Regina 2009 December 1900 (has links)
This study examined the relationship of holistic scoring with handwriting legibility, spelling accuracy and number of T-units within compositions written by children in grades 3 through 6 using path analysis. A sample of 223 compositions was rated for handwriting legibility and composition quality, and coded for number of T-units and percentage of accurately spelled words. Number of T-units was consistently the strongest predictor of holistic scoring across the four grade levels. Handwriting legibility and spelling accuracy yielded varying results in different grade levels.
294

Creation and maintenance of a communication tree in wireless sensor networks

Jung, Eun Jae 15 May 2009 (has links)
A local reconfiguration algorithm (INP) for reliable routing in wireless sensor networks that consist of many static (fixed) energy-constrained nodes is introduced in the dissertation. For routing around crash fault nodes, a communication tree structure connecting sensor nodes to the base station (sink or root) is dynamically reconfigured during information dissemination. Unlike other location based routing approaches, INP does not take any support from a high costing system that gives position information such as GPS. For reconfigurations, INP uses only local relational information in the tree structure among nearby nodes by collaboration between the nodes that does not need global maintenance, so that INP is energy efficient and it scales to large sensor networks. The performance of the algorithm is compared to the single path with repair routing scheme (SWR) that uses a global metric and the modified GRAdient broadcast scheme (GRAB-F) that uses interleaving multiple paths by computation and by simulations. The comparisons demonstrate that using local relative information is mostly enough for reconfigurations, and it consumes less energy and mostly better delivery rates than other algorithms especially in dense environments. For the control observer to know the network health status, two new diagnosis algorithms (Repre and Local) that deal with crash faults for wireless sensor networks are also introduced in the dissertation. The control observer knows not only the static faults found by periodic testing but also the dynamic faults found by a path reconfiguration algorithm like INP that is invoked from evidence during information dissemination. With based on this information, the control observer properly treats the network without lateness. Local algorithm is introduced for providing scalability to reduce communication energy consumption when the network size grows. The performance of these algorithms is computationally compared with other crash faults identification algorithm (WSNDiag). The comparisons demonstrate that maintaining the communication tree with local reconfigurations in Repre and Local needs less energy than making a tree per each diagnosis procedure in WSNDiag. They also demonstrate that providing scalability in Local needs less energy than other approaches.
295

OnPLS : Orthogonal projections to latent structures in multiblock and path model data analysis

Löfstedt, Tommy January 2012 (has links)
The amounts of data collected from each sample of e.g. chemical or biological materials have increased by orders of magnitude since the beginning of the 20th century. Furthermore, the number of ways to collect data from observations is also increasing. Such configurations with several massive data sets increase the demands on the methods used to analyse them. Methods that handle such data are called multiblock methods and they are the topic of this thesis. Data collected from advanced analytical instruments often contain variation from diverse mutually independent sources, which may confound observed patterns and hinder interpretation of latent variable models. For this reason, new methods have been developed that decompose the data matrices, placing variation from different sources of variation into separate parts. Such procedures are no longer merely pre-processing filters, as they initially were, but have become integral elements of model building and interpretation. One strain of such methods, called OPLS, has been particularly successful since it is easy to use, understand and interpret. This thesis describes the development of a new multiblock data analysis method called OnPLS, which extends the OPLS framework to the analysis of multiblock and path models with very general relationships between blocks in both rows and columns. OnPLS utilises OPLS to decompose sets of matrices, dividing each matrix into a globally joint part (a part shared with all the matrices it is connected to), several locally joint parts (parts shared with some, but not all, of the connected matrices) and a unique part that no other matrix shares. The OnPLS method was applied to several synthetic data sets and data sets of “real” measurements. For the synthetic data sets, where the results could be compared to known, true parameters, the method generated global multiblock (and path) models that were more similar to the true underlying structures compared to models without such decompositions. I.e. the globally joint, locally joint and unique models more closely resembled the corresponding true data. When applied to the real data sets, the OnPLS models revealed chemically or biologically relevant information in all kinds of variation, effectively increasing the interpretability since different kinds of variation are distinguished and separately analysed. OnPLS thus improves the quality of the models and facilitates better understanding of the data since it separates and separately analyses different kinds of variation. Each kind of variation is purer and less tainted by other kinds. OnPLS is therefore highly recommended to anyone engaged in multiblock or path model data analysis.
296

Shortest-Path Distance Estimation and Positioning Algorithm in Wireless Sensor Networks

Jou, Yu-Shiuan 20 August 2007 (has links)
The main purpose of this thesis is to utilize landmarks with known coordinates and the distance between a target and landmarks to establish an objective function, and to optimize the objective function by using unconstrained direct search method to estimate the coordinate of target. A number of nodes in the sensor network serve as the landmarks according to landmark selection algorithm. Since the landmark selection algorithm is time-consuming, a simplified scheme that would improve the algorithm is to reuse the distance information that had been computed. Due to the limit of transmission range between nodes, utilizing the shortest-path distance estimation model can quickly estimate the distance between the target and non-adjacent landmarks. The main conception of the model is combining the manner of multi-hop with the shortest-path model. Due to the possible errors in distance estimation, the error per hop is considered for reducing the estimation errors. It will obviously reduce the localization errors of the target. The thesis utilizes unconstrained direct search method to optimize the objective functions such as the simplex evolutionary method (SEM), the cyclic coordinate method(CCM) and the Powell method (PM). CCM and PM will tackle the problem of finding the forward length along search direction. Hence, two schemes that combine CCM or PM with SEM are proposed to resolve the problem. Finally, simulations are conducted to generate random some nodes in an known area and to select landmarks from the nodes. Let the target be assigned in the area and do performance analysis of positioning algorithm. We discuss the performance of the positioning algorithm by considering the error per hop approach. We also discuss the effects on positioning by changing some variables such as the number of nodes, the number of landmarks and the transmission range of nodes. It is seen that the positioning errors will be reduced in examples where the number of landmark are four or the number of node are four hundred. The performance of positioning becomes accurate by reducing the distance estimation error.
297

The Effect of Pre-strain and Strain Path Changes on Ductile Fracture

Alinaghian, Yaser 07 March 2013 (has links)
Industrial metal forming operations generally require several deformation steps in order to create the final product. The mechanical behavior of materials undergoing strain path changes can be very different from those deformed in a given direction to fracture. The work presented here employed laser drilled model materials to better understand the effect of pre-strains and strain path changes on void growth and linkage leading to fracture is studied. The experimental results show that increasing pre-strain results in faster void growth which was justified in terms work hardening rate in the sample. Scanning electron microscope images revealed that the ductility of the sample decreased with increasing pre-strain but only slightly compared to the large decrease in far field strain at failure. This suggests that pre-strain affects strain localization significantly and to a lesser extent the ductility. Finally a finite element model has been built to predict the linkage between voids.
298

Individual and collective rights in Africa and their interrelationships with economics and politics

Latukhina, Maria 19 February 2008
This thesis examines the relationships between various groups of human rights, and the effect of globalization and the state on human rights protection. Two hypotheses are examined in path analysis of fifty-two African counties. The first hypothesis considers the proposition that economic, social, and cultural rights implemented prior to civil and political rights in Africa meet the needs of the population better than primary implementation of civil and political rights. The second hypothesis is that globalization has a negative effect on protection of all human rights and that its impact on rights is generally larger than the impact of the state. Within the context of a multivariate model, my analysis does not support the hypotheses. These findings are discussed with regard to the existing literature and several suggestions are proposed for future research.
299

Feature-rich distance-based terrain synthesis

Rusnell, Brennan 25 February 2009
This thesis describes a novel terrain synthesis method based on distances in a weighted graph. The method begins with a regular lattice with arbitrary edge weights; heights are determined by path cost from a set of generator nodes. The shapes of individual terrain features, such as mountains, hills, and craters, are specified by a monotonically decreasing profile describing the cross-sectional shape of a feature, while the locations of features in the terrain are specified by placing the generators. Pathing places ridges whose initial location have a dendritic shape. The method is robust and easy to control, making it possible to create pareidolia effects. It can produce a wide range of realistic synthetic terrains such as mountain ranges, craters, faults, cinder cones, and hills. The algorithm incorporates random graph edge weights, permits the inclusion of multiple topography profiles, and allows precise control over placement of terrain features and their heights. These properties all allow the artist to create highly heterogeneous terrains that compare quite favorably to existing methods.
300

Motion Control of Rigid Bodies in SE(3)

Roza, Ashton 26 November 2012 (has links)
This thesis investigates the control of motion for a general class of vehicles that rotate and translate in three-space, and are propelled by a thrust vector which has fixed direction in body frame. The thesis addresses the problems of path following and position control. For path following, a feedback linearization controller is presented that makes the vehicle follow an arbitrary closed curve while simultaneously allowing the designer to specify the velocity profile of the vehicle on the path and its heading. For position control, a two-stage approach is presented that decouples position control from attitude control, allowing for a modular design and yielding almost global asymptotic stability of any desired hovering equilibrium. The effectiveness of the proposed method is verified both in simulation and experimentally by means of a hardware-in-the-loop setup emulating a co-axial helicopter.

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