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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.
11

Ovlivnění vybraných aspektů pomocí kinesiotapu u problematiky plaveckého ramena / Affection of chosen aspects by using kinesiotape in swimmers shoulder

Laudová, Petra January 2019 (has links)
This research is focused on "swimmer's shoulder" and on affection of chosen aspects by kinesiotape. Theoretical part describes a summary of knowledge about origin, diagnostic and treatment of swimmer's shoulder. Kinesiotaping as a nowadays treatment method and its effects are also specified. The thesis provides a brief description of chosen aspects (pain, tactile acuity and proprioception) and their measuring by objectification methods. Practical part deals with measuring, evaluation and comparing of mentioned aspects before and after treatment by kinesiotape. Methods: 20 competitive swimmers (average age 18,3 years, SD ± 3,10) with shoulder pain were chosen for investigating and measuring. Pain was observed by visual analog scale (VAS) and pressure algometry, tactile acuity by esthesiomether and proprioception by a special method, all before and after treatment. A control group without kinesiotape was included to the research. Results: The experiment showed that tactile acuity was altered in patients with kinesiotape by 27,5 mm in average. This result was evaluated as statistically significant (p = 0,0023). Although values of pain measured by VAS and pressure algometry were enhanced, they were not very significant on the importace level 0,05 (p = 0,1540, resp. 0,1575). Proprioception was also...
12

Simulation of Cylinder Flows with Gaps

Matthew X Liu (10765134) 10 May 2021 (has links)
This thesis presents results of computations of supersonic flow over finite cylinders with varying geometries at the cylinder-wall juncture. The flow domain and geometries were modeled after experiments conducted at University of Tennessee Space Institute (UTSI). CREATE Kestrel (KCFD) was used to perform improved-delayed detached simulations (IDDES) of the unsteady flow. Time-accurate data were collected via taps along the centerline partially on the surface of the cylinder geometries and on the wall upstream of the cylinder. Spectra of the pressure signals and two-point correlations were computed to compare the flow between the different cases consisting of a baseline cylinder, the cylinder with a smaller gap, and the cylinder with a wider fairing. Properties on the cylinder surface for the gap case had the greatest difference compared to the others. In addition, the spectral content showed higher frequency activity for the gap case on the surface in front of the cylinder. <br>
13

Exploring Fundamental Turbulent Physics Using Direct Numerical Simulation

Nilsson, Michael A 01 January 2009 (has links) (PDF)
It has been shown in many studies that turbulent flows are highly dependent on their initial conditions. This thesis explores turbulent flow using direct numerical simulation (DNS) in a variety of situations, and culminates in the development of physically realizable initial conditions. The reaction of isotropic homogeneous turbulent flow to the instantaneous insertion of a wall is investigated using two-point correlations. A model with which to predict the behavior of the two-point correlations is also proposed. The proposed model utilizes a reflection technique that with a linear operation, it accurately predicts the behavior of the non-linear two point correlations. The model works exceedingly well for correlations involving wall-perpendicular velocities, but does not predict correlations involving only wall-parallel velocities as well. A vorticity approach is covered, in an effort to highlight which parts of the correlation decomposition are important to the prediction of the correlations after wall imposition. The vorticity study also helps highlight why the proposed linear model predicts the flow. The impact of the initial conditions on axisymmetric contraction flow of turbulent flow is examined, and as a consequence new initial conditions are developed based off of a physically realizable flow condition. The development of the new-initial conditions and the resulting fields are covered, as well as a study on the value of the turbulent decay exponent associated with decay of isotropic turbulent velocity fields.
14

Methodology for Determining the Variance of the Taylor Factor: Application in Fe-3%Si

Przybyla, Craig P. 02 November 2005 (has links) (PDF)
The variance of the Taylor factor due to variations in the microstructure and window size is explored using both a random sampling method and a previously developed statistical relationship. The results from the random sampling method correlated well with the statistical variance relationship when the magnitude of the variance was greater than that of the numerical errors observed in the statistical calculation. An empirical relation was developed to model the results and the constants for this relationship were determined for pseudo-three dimensional Fe-3%Si. Implementation of the statistical variance relationship in true 3D microstructures is not limited by material opacity, since it depends only upon the 2-point pair correlation functions. The connection between the variance of the R-value and variance of the Taylor factor is considered. Although only a weak connection was found, it was observed that relatively small variations in the Taylor factor yield large variances in the R-value.
15

The Effect of Chronic Mild to Moderate Neck Pain on Neck Function as Measured by Joint Reposition Error and Tactile Acuity of the Cervical Dermatomes

Cheever, Kelly Martell 26 June 2014 (has links) (PDF)
The purpose of this study was to observe the joint reposition error and tactile acuity of patients with chronic mild to moderate neck pain and compare those values to healthy controls to further investigate the effect of neck pain on neck function and the need for sensorimotor training in patients with chronic neck pain. In spite of some inconsistencies in the literature and methodology, both the two-point discrimination test and the joint reposition error test can give clinicians valuable, inexpensive and quick objective data that can be used in the diagnostic portion of an examination as well as in designing and assessing change during a rehabilitation program. This study found a significant increase in neck joint reposition error (JRE) in flexion in participants suffering from neck pain when compared to healthy controls. JRE averaged 2.75° ± 1.52° in flexion healthy controls and 4.53° ± 1.74° in flexion in participants with chronic neck pain. Additionally, the dermatome found to be most affected by neck pain was C5. Further research is needed to examine both the effect of proprioceptive training on neck pain and the effectiveness of the two-point discrimination threshold test and the joint reposition error test as diagnostic tools and indicators of progress in the treatment of chronic neck pain.
16

The Two Point Correlation Structure of a Cylinder Wake

Molinaro, Nicholas Joseph 30 June 2017 (has links)
In this study the complete four dimensional space time correlation function was measured in the wake of an untripped circular cylinder at a Reynolds number of 60 000. This correlation serves as the complete inflow boundary condition for an open rotor ingesting inhomogeneous turbulence. An important aspect of the turbulence ingestion problem is understanding how different inflow boundary conditions effect the sound produced by a rotor. In the present study the turbulence structure of two plane wakes were compared. Measurements completed by a previous study in the wake of a NACA 0012 airfoil were compared with the measurements completed by the present study in the wake of a cylinder. The mean flows of both plane wakes were found to be very similar, however the Reynolds stress profiles show that the cylinder wake is substantially more turbulent. The structures of the two-point correlation function in each wake are also similar, although the cylinder wake had greater maximum correlation values and was correlated at greater separations. The two-point correlation was used along with proper orthogonal decomposition to compute the average instantaneous velocity fields of both wake flows. These velocity fields represent the average eddy structures present in each wake flow. The eddy structure comparisons show that the structures in the cylinder wake are larger and better correlated at longer time delays. / Master of Science
17

Prediction of Trailing Edge Noise from Two-Point Velocity Correlations

Spitz, Nicolas 29 June 2005 (has links)
This thesis presents the implementation and validation of a new methodology developed by Glegg et al. (2004) for solving the trailing edge noise problem. This method is based on the premises that the noise produced by a surface can be computed by the integral of the cross product between the velocity and vorticity fields, of the boundary layer and shed vorticity (Howe (1978)). To extract the source terms, proper orthogonal decomposition is applied to the velocity cross spectrum to extract modes of the unsteady velocity and vorticity. The new formulation of the trailing edge noise problem by Glegg et al. (2004) is attractive because it applies to the high frequencies of interest but does not require an excessive computational effort. Also, the nature of the formulation permits the identification of the modes producing the noise and their associated velocity fluctuations as well as the regions of the boundary layer responsible for the noise production. The source terms were obtained using the direct numerical simulation of a turbulent channel flow by Moser et al. (1998). Two-point velocity and vorticity statistics of this data set were obtained by averaging 41 instantaneous fields. For comparisons purposes, experimental boundary layer data by Adrian et al. (2000) was chosen. Statistical reduction of 50 velocity fields obtained by particle image velocimetry was performed and analysis of the two-point correlation function showed features similar to the DNS data case. Also, proper orthogonal decomposition revealed identical dominant modes and eddy structures in the flow, therefore justifying considering the channel flow as an external boundary layer for noise calculations. Comparison of noise predictions with experimental data from Brooks et al. (1989) showed realistic results with the largest discrepancies, on the order of 5 dB, occurring at the lowest frequencies. The DNS results are least applicable at these frequencies, since these correspond to the longest streamwise lengthscales, which are the most affected by the periodicity conditions used in the DNS and also are the least representative of the turbulence in an external boundary layer flow. Most of the noise was shown to be produced by low-frequency streamwise velocity modes in the bottom 10% of the boundary layer and locations closest to the wall. Only 6 modes were required to obtain noise levels within 1 dB of the total noise. Finally, the method for predicting spatial velocity correlation from Reynolds stress data in wake flows, originally developed by Devenport et al. (1999, 2001) and Devenport and Glegg (2001), was adapted to boundary-layer type flows. This method, using Reynolds stresses and the prescription of a lengthscale to extrapolate the full two-point correlation, was shown to produce best results for a lengthscale prescribed as proportional to the turbulent macroscale. Noise predictions using modeled two-point statistics showed good agreement with the DNS inferred data in all but frequency magnitude, a probable consequence of the modeling of the correlation function in the streamwise direction. Other quantities associated to noise were seen to be similar to the ones obtained using the DNS. / Master of Science
18

Tent-maps, two-point sets, and the self-Tietze property

Davies, Gareth January 2011 (has links)
This thesis discusses three distinct topics. A topological space X is said to be self- Tietze if for every closed C eX, every continuous f: C -+ X admits a continuous extension F: X -+ X. We show that every disconnected, self- Tietze space is ultranormal. The Tychonoff Plank is an example of a compact self- Tietze space which is not completely normal, and we establish that a completely normal, zero- dimensional, homogeneous space need not be self- Tietze. A subset of the plane is a two-point set if it meets every straight line in exactly two points. We show that a two-point set cannot contain a dense G8 subset of an arc. We also show that the complement of a two-point set is necessarily path-connected. Finally, we construct a zero-dimensional subset of the plane of which the complement is simply-connected. For A E lR, the tent-map with slope A is the function f: [0, 1] -+ lR such that f(x) = AX for x :=:; ~ and f(x) = A(l - x) for x ~ ~. Properties of w-limit sets of tent-maps, i.e. sets of the form n {fn+k(x) I kEN} nEN for x E [0,1], are examined, and an example of a tent-map and a closed, invariant, nonempty, internally chain transitive subset of [0, 1] which is not an w-limit set is given.
19

Lokální změna diskriminačního čití nad myofasciálním trigger pointem / Myofascial Trigger point and Two point discrimination changes in MTrP region

Homolka, Pavel January 2010 (has links)
The main purpose of this thesis, called The local changes in discriminatory sensation above a myofascial Trigger Point, was to assess the relationship of a local nociception in the form of the myofascial Trigger Point to the local discriminatory sensation. Based on the theoretical information, hypothesis concerning the relationship of MTrP and two point discrimination were experimentally checked. The subject of the research was the trigger point trapezius pars ascendens. Localized MTrP was clinically evaluated in terms of both static and dynamic factors. Using a palpometer, its sensitivity by level of pressure generated pain (pressure generated pain threshold) was rated. The quality of two-point discrimination was rated as well. Furthermore it was also rated how a made isometric relaxation changed the sensitivity as nociceptive so discriminatory. Discriminatory sensation (attention threshold (AT-TPD), stable threshold (SSV-TPD)) in the region above the trigger point was measured by a mechanical caliper with modified tips radius of 1mm. Generally 23 probands were examined, 11 of them had simultaneously diagnosed a presence of the constitutional hypermobility. The results of the work confirmed that the made isometric relaxation had a significant influence on the change of thresholds discrimination of two...
20

Objektivizace operační léčby syndromu karpálního tunelu / Objectification of surgical treatment of carpal tunnel syndrome

Dvořáková, Marie January 2011 (has links)
Title: Objectification of surgical treatment of carpal tunnel syndrome Objectives: The main aim of this work is to evaluate the effectiveness of surgical treatment of carpal tunnel syndrome. Methods: In this work was used a two-point discrimination test, that evaluated tactile sensory of the hand with carpal tunnel syndrome. It evaluated the change of discriminatory sensation after surgical treatment of carpal tunnel syndrome. The results of testing were evaluated by using the SigmaPlot statistic program SigmaStat 9.01 to 3.1 integration. Results: Research found that two-point discrimination in region of median nerve innervated is improved by surgical treatment of carpal tunnel syndrome, it improves the tactile sensory of the hand, which is impaired by carpal tunnel syndrome. Effect of physiotherapy on improvement of the discriminatory sensation after surgery was not demonstrated. However, the physiotherapy after surgical treatment of carpal tunnel syndrom is important. Keywords: carpal tunnel syndrome, sensory discrimination, a two-point discrimination test

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