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Prospective Comparison of Methods for Assessment of Headache DirectionalityHoffman, Carmen 30 March 2018 (has links)
A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Response to prophylactic treatment of migraine
with Onabotulinumtoxin A (BTX-A) has been noted to be significantly correlated to the perceived
direction of headache pain, namely imploding vs. exploding subtype. This study analyzed 3 methods
of assessing migraine directionality in comparison to a 30-day headache log; pictorial
representation, written description, and physician assessment. Each of these assessment types was
shown to have poor agreement with the headache log at the initial visit. However, all 3 assessments
displayed excellent agreement at the return visit, as well as significantly improved confidence in
patient ability to determine headache directionality.
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Vertical Directionality Analysis of Low Frequency Ambient Noise in South China Sea Experiment of ASIAEXLin, Po-Chang 19 August 2004 (has links)
This study is based upon the vertical line array (VLA) in South China Sea experiment of the Asian Seas International Acoustic Experiment (ASIAEX), dated from May 3, 2001 to May 16, 2001, in which the ambient noise in shallow water was measured. In this paper, we use the beamforming method to calculate the vertical directionality of ambient noise in shallow water, for discussing the noise source distribution, and environmental effects on vertical directionality. The results show that distant shipping noise was observed near the horizontal angles, and surface noise occurred at high grazing angles. It is also discussed that the wind speed effect on the vertical directionality in this paper. Because of the typhoon Cimaron passed the experimental area during the experiment, which make wind speed changed obviously, so it can be found out the wind effect of ambient noise. By analyze the noise fluctuation, it is concluded that the threshold frequency of wind wave affected ambient noise levels were about 400 Hz. And after analyzing the vertical directionality, it is verified that the threshold was lower to 200 Hz. On the other hand, we also note the phenomena of ¡§noise notch¡¨ appeared at some duration when calculating the vertical directionality. The environmental effects (sound speed profile) on the notch, and the presentation of noise notch at different frequencies were discussed. In the end part of this paper, we determined the time when the notch occurred by using the power difference of vertical directionality, and we expect that the results would be important for similar researches in the future.
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Reciprocity-based imaging using multiply scattered wavesRavasi, Matteo January 2015 (has links)
In exploration seismology, seismic waves are emitted into the structurally complex Earth. Its response, consisting of a mixture of arrivals including primary reflections, conversions, multiples, and transmissions, is used to infer the internal structure and properties. Waves that interact multiple times with the inhomogeneities in the medium probe areas of the subsurface that are sometimes inaccessible to singly scattered waves. However, these contributions are notoriously difficult to use for imaging because multiple scattering turns out to be a highly nonlinear process. Conventionally, imaging algorithms assume singly scattered energy dominates data. Hence these require that energy that scatters more than once is attenuated. The principal focus of this thesis is to incorporate the effect of complex nonlinear scattering in the construction of subsurface elastic images. Reciprocity theory is used to establish an exact relation between the full recorded data and the local (zero-offset, zero-time) scattering response in the subsurface which constitutes our image. Fully nonlinear, elastic imaging conditions are shown to lead to better illumination, higher resolution and improved amplitudes in pure-mode imaging. Strikingly it is also observed that when multiple scattering is correctly handled, no converted-wave energy is mapped to any image point. I explain this result by noting that conversions require finite time and space to manifest. The construction of wavefield propagators (Green’s functions) that are used to extrapolate recorded data from the surface to points in the Earth’s interior is a crucial component of any imaging technique. Classical approaches are based on strong assumptions about the propagation direction of recorded data, and their polarization; preliminary steps of wavefield decomposition (directional and modal) are required to extract upward propagating waves at the recording surface and separate different wave modes. These algorithms also generally fail to explain the trajectories of multiply scattered and converted waves, representing a major problem when constructing nonlinear images as we do not know where such energy interacted with the scatterers to be imaged. A secondary aim of this thesis is to improve on the practice of wavefield extrapolation or redatuming by taking advantage of the different nature of multi-component data compared with single-mode acoustic data. Two-way representation theorems are used to define novel formulations in elastic media which allow both up- and downward propagating fields to be back-propagated correctly without ambiguity in the direction, and such that no cross-talk between wave modes is generated. As an application of directional extrapolation, the acoustic counterpart of the new approach is tested on an ocean-bottom cable field dataset acquired over the Volve field, North Sea. Interestingly, the process of redatuming sources to locations beneath a complex overburden by means of multi-dimensional deconvolution also requires preliminary wavefield separation to be successful: I propose to use the two-way convolution-type representation as a way to combine full pressure and particle velocity recordings. Accurate redatumed wavefields can then be obtained directly from multi-component data without separation. Another major challenge in seismic imaging is to construct detailed velocity models through which recorded data will be extrapolated. Nowadays the information contained in the extension of subsurface images along either the time or space axis is commonly exploited by velocity model building techniques acting in the image domain. Recent research has shown that when both extensions are taken into account, it is possible to estimate the data that would have been recorded if a small, local seismic survey was conducted around any image point in the subsurface. I elaborate on the use of nonlinear elastic imaging conditions to construct such so-called extended image gathers: missing events, incorrect amplitudes, and spurious energy generated from the use of only primary arrivals are shown to be mitigated when multiple scattering is included in the migration process. Finally, having access to virtual recordings in the subsurface is also very useful for target-oriented imaging applications. In the context of one-way representation, I apply the novel methodology of Marchenko redatuming to the Volve field dataset as a way to unravel propagation effects in the overburden structure. Constructed wavefields are then used to synthesize local, subsurface reflection responses that are only sensitive to local heterogeneities, and detailed images of target areas of the subsurface are ultimately produced. Overall the findings of this thesis demonstrate that, while incorporating multiply scattered waves as well as multi-component data in imaging may be not a trivial task, such information is vital for achieving high-resolution and true-amplitude seismic imaging.
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Treatment Moderation and Secondary Outcomes: Results from a Randomized Clinical TrialMotoca, Luci M. 28 June 2012 (has links)
The present study pursued two objectives in the context of a randomized clinical trial of cognitive-behavioral therapy with parent (CBT/P) and group (GCBT) involvement. The first objective was to examine the variability in treatment outcome. There were three specific aims within the first objective, to evaluate: (1) youth characteristics (age, depressive, and externalizing disorders) as moderators of treatment outcome; (2) the differential outcome of the treatment approaches as a function of youth characteristics; and (3) the relative efficacy of the treatment approaches at each level of the moderators.
The second objective was to evaluate the efficacy of anxiety treatments along secondary depressive symptoms and externalizing behaviors. There were five specific aims within the second objective, to evaluate: (1) whether anxiety treatment yields reductions in secondary problems, (2) the efficacy of anxiety treatments in reducing secondary problems as a function of approach and youth characteristics, (3) whether reductions in anxiety symptoms significantly mediate changes in secondary problems, (4) the directionality of change in the hypothesized mediated relations, and (5) whether the hypothesized mediated relations are moderated by treatment approach and youth characteristics. The specific aims were pursued using data collected from 183 youth and their mothers. Research questions were tested using multiple regressions and structural equation modeling.
Age, depressive, and externalizing disorders were significant moderators. CBT/P relative to GCBT lowered anxiety more for younger than older youth. GCBT relative to CBT/P lowered anxiety more for older than younger youth. GCBT relative to CBT/P lowered anxiety more for depressed youth than non-depressed youth. GCBT relative to CBT/P lowered anxiety less for externalizing youth than non-externalizing youth. Treatment reduced depressive symptoms and externalizing problem behaviors. Reductions in anxiety mediated changes in depressive symptoms and externalizing problem behaviors. Reversed directionality was found in the relation between social anxiety and depressive symptoms. In CBT/P the direction of change was from depressive to social anxiety. The opposite was true in GCBT. Reductions in social anxiety mediated posttreatment changes in depressive symptoms in GCBT but not CBT/P. The reverse was true at follow-up. Reductions in social anxiety mediated changes in depressive symptoms for girls but not boys.
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The influence of directionality of French and English interpreters at the Pan-African ParliamentKoumba, Christian 28 August 2014 (has links)
Thesis (M.A.)--University of the Witwatersrand, Faculty of Humanities, School of Literature, Language and Media (Translation and Interpreting Studies), 2014 / As Herbert indicates (1952:82), “it is quite clear that in diplomatic conference the greatest attention should be paid to all nuances of words; while in gathering of scholars, technical accuracy will have greater importance; in a literary and artistic gathering, elegance of speech; and in a political assembly, forcefulness of expression.”
This study aims to assess the impact of directionality on French and English interpreters working for the Pan-African Parliament (PAP). Directionality is whether interpreters should work from their B language or acquired language, into their A language or their native language (AIIC: 1999). Supporters of B-to-A interpreting indicate that interpreters are not at ease cognitively when interpreting from the A language into the B language due to more effort required to find corresponding expressions in their B language (e.g., Donovan, 2003; Seleskovitch, 1999). Those in favour of A-to-B interpreting, on the other hand, affirm that interpreters’ better comprehension of their native language may help them produce a more complete and reliable interpretation (Denissenko, 1989; Williams, 1995). This study explores the performance of French/English simultaneous interpreters in both directions by focusing on norms and strategies. The data for the study was gathered by means of questionnaire interviews and the recording of ten professional interpreters’ simultaneous interpretation performance during the Pan-African sessions and committees which took place in October 2013. The simultaneous interpreting processes of interpreters were analysed according to certain norms such as: accuracy, fluency and quality, and according to the strategies that they customise to avoid the traps contained in the source speeches of the parliamentarians. This study will assess whether or not French/English interpreters at the Pan-African Parliament do their work accordingly and with confidence when they are required to interpret in both directions. Directionality has to be understood well for interpreters to deliver quality interpreting required for good communication amongst parliamentarians.
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Diensleer : van staties na dinamiesPretorius, J.P.H., Lategan, L.O.K., Hay, H.R. January 2008 (has links)
Published Article / Service-learning is a relatively new teaching and learning method which has been implemented with success at national and international tertiary institutions. The identification and elucidation of the terms and processes that delineate the dynamic character of service-earning satisfactorily pose a particular challenge to researchers within the service-learning environment. Since a degree of confusion still exists amongst researchers and decision-makers regarding the distinguishing characteristics of service-learning as opposed to other forms of experiential learning, it is essential to indicate the specific position of service-learning within this environment.
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Application of Adaptive Algorithm on Analysis of Spatial Energy of Ocean Ambient NoiseCheng, Ni-hung 23 July 2009 (has links)
Ocean ambient noise is one of factors that can affect the performance of sonar and underwater communication system, it can degrade the performance of sonar system on listening or active detection, and also can affect the quality of underwater communication. Due to the variation of temperature and density in the ocean which make ambient noise has directionality. Beamforming can analyze the directionality of noise energy. Conventional beamforming is based on the assumption of plane wave sound field, so the energy from each angle is obtained by linear accumulation of every element. However plane wave assumption may not be satisfied because of the boundary interactions of sound propagation and energy attenuation of water column, therefore conventional beamforming may have poor beam resolution and SNR in applications. This research is to study of the influence of spatial coherence of ambient noise on beam resolution, and to improve the beam resolution by using the adaptive algorithm from the communication system theory. Firstly, simulations were performed to study spatial coherence between plane wave and non-plane wave in ambient noise, and the results were compared with beam resolution. This research also analyzes the influence of different conditions of noise spatial coherence on beamforming with ASIAEX data. The results showed that ambient noise has lower spatial coherence at high frequency, and the beamforming has poor beam resolution because of the lower spatial coherence in noise. Therefore, the adaptive beamforming were performed to improve the beam resolution, and compared with the conventional beamforming. The results showed that the highest improvement on beam resolution is 42.9 %, and increased SNR by 6 dB. On the other hand, the application of ASIAEX data show that, the highest improvement on beam resolution is 40.0 %, and increased SNR by 8 dB. The noise notch of ambient noise became more significant by increasing in beam resolution, and it also promoted the accuracy of analysis on noise directionality.
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A study of the relationship between reversals and several factors in the Grade 2 leanerSmith, Wendy 14 October 2009 (has links)
The study examined the relationship between reversals and several factors in 141 Grade 2 mainstream learners from average classes in Department of Education schools. The sample consisted of 77 female learners and 64 male learners. 55 of the 141 learners were older than 8 years and 131 of the 141 learners were right-handed.The study made use of correlational research where two or more variables are compared by measuring differences and looking for a relationship. Incorrect letter formation, gender and reversals in reading showed a statically significant difference between the group who had reversals compared to the group that did not have reversals in the class program that was used to identify learners with reversals. Furthermore the data collected only on the learners with reversals showed a mean scaled that was below average for position in space, figure ground and visual closure as well as for the motor-reduced quotient of the Developmental Test of Visual Perception -2. This group also displayed a high percentage of learners with difficulty with directionality as well as with crossing their midline. The results of the study were limited by the research design, as well as the lack of standardized tests available to test some aspects. Difficulty in gaining permission from parents to include learners in the study was also experienced which limited the final sample size. Further studies focussing on the treatment of the factors that showed a statistically significant relationship with reversals was recommended as well as placing more emphasis correct letter formation when teaching handwriting and publishing the results of this study in a journal accessible to educators and therapists was recommended. Copyright / Dissertation (MOccTher)--University of Pretoria, 2009. / Occupational Therapy / unrestricted
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EFFECT OF BUILDING ORIENTATION ON STRUCTURAL RESPONSE OF REINFORCED CONCRETE MOMENT RESISTING FRAME STRUCTURESParsa, Amanullah 01 May 2020 (has links)
In time history analysis of structures, the geometric mean of two orthogonal horizontal components of ground motion in the as-recorded direction of sensors, have been used as measure of ground motion intensity prior to the 2009 NEHRP provision. The 2009 NEHRP Provisions and accordingly the seismic design provisions of the ASCE/SEI 7-10, modified the definition of ground motion intensity measure from geometric mean to the maximum direction ground motion, corresponding to the direction that results in peak response of the oscillator. Maximum direction response spectra are assumed to envelope the range of maximum possible responses over all nonredundant rotation angles. Two assumptions are made in the use maximum ground motion as the intensity measure: (1) the structure’s strength and stiffness properties are identical in all directions and (2) azimuth of the maximum spectral acceleration coincides with the one of the principal axes of the structure. The implications of these assumptions are examined in this study, using 3D computer models of multi-story structures having symmetric and asymmetric layouts and elastic vibration period of 0.2 second and 1.0 second subjected to a set of 25 ground-motion pairs recorded at a distance of more than 20 km from the fault. The influence of the ground-motion rotation angle on structural response (here lateral displacement and story drift) is examined to form benchmarks for evaluating the use of the maximum direction (MD) ground motions. The results of this study suggest that while MD ground motions do not always result in largest structural response, they tend to produce larger response than the as-recorded ground motions. On the other hand, more research on non-linear seismic time history analysis is recommended, especially for asymmetric layout plan buildings.
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Analýza strukturálních změn nanovlákenných scaffoldů vzhledem k jejich relativnímu prodloužení / Analysis of structural changes of nanofiber scaffolds in relation with their relative extensionMorávek, Martin January 2016 (has links)
The goal of this thesis was to find a suitable method for evaluating structural changes of scaffolds as influenced by external mechanical pressure and to verify the validity of hypothesis which assumes a change of directionality of fibers and also thinning of fibers according to the stretching of a scaffold. Assumptions formulated in these three hypothesis were tested on a scaffold with a plasma surface treatment and without any plasma surface treatment. To examine structural changes an electrone microscope was used to observe the surface of scaffolds. Incurred photos were then processed with the help of automatic software picture analysis and observed data were statisticly evaluated. The result of this experiment is a description of used method which can be used in future for larger studies. It was found that by the effect of external mechanical pressure fibers of examinated scaffolds turn in the direction of the pull. It has also been found that the average thickness of fibers didn't change. Results of this work give insight into the evaluation of structural changes of scaffolds when pressured by an external mechanical power and open possibilities for deeper and more exact research in this field. Key words: scaffold, picture analysis, fiber directionality, fiber thickness.
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