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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.
1

The Effect of Head Flexion/extension on Acoustic Measures of Singing Voice Quality

Knight, Elizabeth Johnson 08 1900 (has links)
A study was undertaken to identify the effect of head flexion/extension on singing voice quality. The amplitude of the fundamental frequency (F0), and the singing power ratio (SPR), an indirect measure of singer’s formant activity, were measured. F0 and SPR scores at four experimental head positions were compared with the subjects’ scores at their habitual positions. Three vowels and three pitch levels were tested. F0 amplitudes and low frequency partials in general were greater with more extended head positions, while SPR increased with neck flexion. No effect of pitch or vowel was found. Gains in SPR appear to be the result of damping low frequency partials rather than amplifying those in the singer’s formant region. Raising the amplitude of F0 is an important resonance tool for female voices in the high range, and may be of benefit to other voice types in resonance, loudness, and laryngeal function.
2

"Efeitos da desprogramação neuromuscular da mandíbula, segundo a filosofia de Roth, sobre as posições da cabeça e da coluna cervical, em indivíduos assintomáticos com maloclusão de classe I" / The effect of mandibular neuromuscular deprogramming, according to Roth’s philosophy, on the positions of the head and the cervical column, in asymptomatic subjetcs with Class I malocclusion

Andrighetto, Augusto Ricardo 04 August 2006 (has links)
O propósito do presente estudo foi determinar, radiograficamente, os efeitos da desprogramação neuromuscular, por meio do uso da placa miorrelaxante superior, na posição craniocervical. A desprogramação neuromuscular foi feita objetivando-se realizar o diagnóstico ortodôntico com a mandíbula em relação cêntrica (RC), de acordo com filosofia de Roth (1981). Foram avaliados 39 indivíduos assintomáticos, com maloclusões Classe I de Angle, separados em dois grupos, o controle, contendo 15 indivíduos, com média de idade de 26 anos, não submetidos a qualquer forma de tratamento, e o tratado, contendo 24 indivíduos, com média de idade de 23 anos e 10 meses, submetidos à desprogramação neuromuscular. De cada paciente, foram obtidas duas telerradiografias em norma lateral, na posição natural da cabeça (PNC). No grupo controle, o intervalo médio entre ambas foi 6 meses e 17 dias. No grupo tratado, a primeira telerradiografia foi realizada previamente, e a segunda, após a desprogramação neuromuscular. O tempo médio de uso da placa miorrelaxante foi de 6 meses e 7 dias. A análise cefalométrica craniocervical foi realizada avaliando-se as angulações craniovertical (SN/VER), craniocervical (OPT/SN e CVT/SN), cervicohorizontal (OPT/HOR e CVT/HOR) e o ângulo da curvatura cervical (OPT/CVT). Concluíu-se que houve extensão significativa da cabeça, tanto em relação à linha vertical verdadeira, demonstrada pelo aumento do ângulo SN/VER, quanto à coluna cervical, demonstrada pelo aumento do ângulo CVT/SN. A coluna cervical apresentou alteração significativa em sua inclinação, em relação à linha horizontal verdadeira, demonstrado pelo aumento do ângulo CVT/HOR. Não houve alteração significativa da curvatura cervical. Foram, ainda, observadas correlações significativas entre as alterações das variáveis SN/VER e OPT/HOR, SN/VER e CVT/HOR, SN/VER e CVT/SN, OPT/CVT e OPT/HOR, OPT/CVT e OPT/SN, OPT/HOR e CVT/HOR, OPT/HOR e OPT/SN, assim como OPT/SN e CVT/SN. / The purpose of this study was to determine, radiographically, the effect of neuromuscular deprogramming, through the use of an upper occlusal splint, on the craniocervical position. Neuromuscular deprogramming was performed in order to carry out orthodontic diagnosis with the mandible in centric relation (CR), according to Roth’s philosophy. Thirthy nine asymptomatic individuals, presenting Angle's Class I malocclusion, were evaluated. The sample was allocated into two groups, the control or untreated group (n=15), with mean age of 26 years, that was followed about 6 months and 17 days, and the treated group (n=24), with mean age of 23 years and 10 months. Two lateral radiographs in natural head position (NHP) were taken from each subject, one before and the other one after neuromuscular deprogramming. The average usage period of the occlusal splint was 6 months and 7 days. Craniocervical cephalometric analysis was carried out by evaluating the craniovertical (SN/VER), craniocervical (OPT/SN and CVT/SN), and cervicohorizontal (OPT/HOR and CVT/HOR) angles, as well as the angle of the cervical curve (OPT/CVT). No significant changes were seen in the control group. It was concluded that there was a significant extension of the head, both in relation to the true vertical line, as demonstrated by the increase of the SN/VER angle, and to the cervical column, as demonstrated by the increase of the CVT/SN angle. Likewise, the cervical column showed significant backward inclination in relation to the true horizontal line, as demonstrated by increase of the CVT/HOR angle. No significant alteration of the cervical curve was observed. In addition, significant correlation coefficients were observed between the differences of the pre- and post-deprogramming values of the measurements the measurements SN/VER and OPT/HOR, SN/VER and CVT/HOR, SN/VER and CVT/SN, OPT/CVT and OPT/HOR, OPT/CVT and OPT/SN, OPT/HOR and CVT/HOR, OPT/HOR and OPT/SN, and OPT/SN and CVT/SN.
3

Natural head position: a photographic method and an evaluation of cranial reference planes in cephalometric analysis.

Madsen, David Peter. January 2007 (has links)
Commonly used craniofacial reference planes such as Frankfort Horizontal (FH) and sella nasion (SN) have shortcomings including their variable inter-individual orientation when related to true horizontal (HOR). Therefore, the aim of this study was to evaluate the potential usefulness of a range of craniofacial reference planes to HOR including those which have not been investigated before: Krogman-Walker line (KW line), neutral horizontal axis, foramen magnum line and posterior maxillary plane. A sample of 57 (38 female, 19 males) consecutive, pre-treatment orthodontic subjects aged 12 to 18 were photographically recorded in a standing mirror guided natural head position (NHP). Cephalograms taken at the same time were traced, oriented to a plumb line (true vertical) transferred from the photograph, and measured for statistical analysis. Thirty nine of these subjects were photographically recorded 2 months later to test the reproducibility of NHP. The results showed that the variability of the 11 selected craniofacial reference planes related to HOR was generally high. The planes illustrating lowest variability to HOR were FH and KW line with standard deviations of 4.6° and 4.7°, respectively. These, however, showed about double the variation in NHP reproducibility (Dahlberg 2.1°). The KW line and palatal plane were also oriented closest to HOR on average. Therefore, KW line and palatal plane are potential substitutes for the commonly used reference planes in the absence of a reliable NHP. However, NHP still represents a more valid craniofacial reference system than the investigated reference planes. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1297323 / Thesis (D.Clin.Dent.) - School of Dentistry, (Orthodonitics), 2007
4

"Efeitos da desprogramação neuromuscular da mandíbula, segundo a filosofia de Roth, sobre as posições da cabeça e da coluna cervical, em indivíduos assintomáticos com maloclusão de classe I" / The effect of mandibular neuromuscular deprogramming, according to Roth’s philosophy, on the positions of the head and the cervical column, in asymptomatic subjetcs with Class I malocclusion

Augusto Ricardo Andrighetto 04 August 2006 (has links)
O propósito do presente estudo foi determinar, radiograficamente, os efeitos da desprogramação neuromuscular, por meio do uso da placa miorrelaxante superior, na posição craniocervical. A desprogramação neuromuscular foi feita objetivando-se realizar o diagnóstico ortodôntico com a mandíbula em relação cêntrica (RC), de acordo com filosofia de Roth (1981). Foram avaliados 39 indivíduos assintomáticos, com maloclusões Classe I de Angle, separados em dois grupos, o controle, contendo 15 indivíduos, com média de idade de 26 anos, não submetidos a qualquer forma de tratamento, e o tratado, contendo 24 indivíduos, com média de idade de 23 anos e 10 meses, submetidos à desprogramação neuromuscular. De cada paciente, foram obtidas duas telerradiografias em norma lateral, na posição natural da cabeça (PNC). No grupo controle, o intervalo médio entre ambas foi 6 meses e 17 dias. No grupo tratado, a primeira telerradiografia foi realizada previamente, e a segunda, após a desprogramação neuromuscular. O tempo médio de uso da placa miorrelaxante foi de 6 meses e 7 dias. A análise cefalométrica craniocervical foi realizada avaliando-se as angulações craniovertical (SN/VER), craniocervical (OPT/SN e CVT/SN), cervicohorizontal (OPT/HOR e CVT/HOR) e o ângulo da curvatura cervical (OPT/CVT). Concluíu-se que houve extensão significativa da cabeça, tanto em relação à linha vertical verdadeira, demonstrada pelo aumento do ângulo SN/VER, quanto à coluna cervical, demonstrada pelo aumento do ângulo CVT/SN. A coluna cervical apresentou alteração significativa em sua inclinação, em relação à linha horizontal verdadeira, demonstrado pelo aumento do ângulo CVT/HOR. Não houve alteração significativa da curvatura cervical. Foram, ainda, observadas correlações significativas entre as alterações das variáveis SN/VER e OPT/HOR, SN/VER e CVT/HOR, SN/VER e CVT/SN, OPT/CVT e OPT/HOR, OPT/CVT e OPT/SN, OPT/HOR e CVT/HOR, OPT/HOR e OPT/SN, assim como OPT/SN e CVT/SN. / The purpose of this study was to determine, radiographically, the effect of neuromuscular deprogramming, through the use of an upper occlusal splint, on the craniocervical position. Neuromuscular deprogramming was performed in order to carry out orthodontic diagnosis with the mandible in centric relation (CR), according to Roth’s philosophy. Thirthy nine asymptomatic individuals, presenting Angle's Class I malocclusion, were evaluated. The sample was allocated into two groups, the control or untreated group (n=15), with mean age of 26 years, that was followed about 6 months and 17 days, and the treated group (n=24), with mean age of 23 years and 10 months. Two lateral radiographs in natural head position (NHP) were taken from each subject, one before and the other one after neuromuscular deprogramming. The average usage period of the occlusal splint was 6 months and 7 days. Craniocervical cephalometric analysis was carried out by evaluating the craniovertical (SN/VER), craniocervical (OPT/SN and CVT/SN), and cervicohorizontal (OPT/HOR and CVT/HOR) angles, as well as the angle of the cervical curve (OPT/CVT). No significant changes were seen in the control group. It was concluded that there was a significant extension of the head, both in relation to the true vertical line, as demonstrated by the increase of the SN/VER angle, and to the cervical column, as demonstrated by the increase of the CVT/SN angle. Likewise, the cervical column showed significant backward inclination in relation to the true horizontal line, as demonstrated by increase of the CVT/HOR angle. No significant alteration of the cervical curve was observed. In addition, significant correlation coefficients were observed between the differences of the pre- and post-deprogramming values of the measurements the measurements SN/VER and OPT/HOR, SN/VER and CVT/HOR, SN/VER and CVT/SN, OPT/CVT and OPT/HOR, OPT/CVT and OPT/SN, OPT/HOR and CVT/HOR, OPT/HOR and OPT/SN, and OPT/SN and CVT/SN.
5

The reliability, practicality and acceptability of using ultrasonography to monitor the progress of labour and delivery

Wiafe, Yaw Amo January 2018 (has links)
Introduction: It had been suggested by a number of recent studies that ultrasonography could become an alternative to digital vaginal examination (VE) for assessing the progress of pregnant women in labour. However, no systematic review and meta-analysis on the effectiveness of ultrasonography was available. Systematic Review: A systematic review and meta-analysis was conducted to investigate the success rate of ultrasonography in comparison with digital VE and the level of agreement between the two methods, in terms of estimating fetal head position, head station and cervical dilatation. Systematic Review Findings: This review found that ultrasonography has a higher success rate than digital VE in estimating fetal head position. Ultrasonography was also in high agreement with digital VE in estimating cervical dilatation, with insignificant difference in the success rate of the two methods in terms of detecting cervical dilatation. There was also a significant correlation between the two methods in estimating head station. However, it was also found by the review that, existing primary studies were mainly conducted in tertiary settings of developed countries. Further research was therefore needed from the perspective of non-tertiary settings and also from developing country settings. In addition, further research was also needed to assess the diagnostic performance of ultrasound in detecting active labour, since it is associated with cervical dilatation. The diagnostic performance of ultrasound in detecting engaged fetal head had also not been investigated, which is necessary because it is associated with head station. Primary Research Aim: As a consequence of these systematic review findings, a primary study was conducted in another clinical setting in a developing country. The aim was to investigate the reproducibility, practicality and acceptability of using ultrasonography to monitor the progress of pregnant women in labour. Research Methods: A cross-sectional study was conducted in a teaching hospital in Ghana. The agreement between ultrasound and digital VE was statistically analysed for the estimation of fetal head position, head station and cervical dilatation. Further statistical analysis was conducted on the diagnostic performance of ultrasound in detecting engaged fetal head, and the diagnostic performance of ultrasound in detecting active labour. A quantitative survey of mothers’ acceptance of intrapartum ultrasound was also conducted. Lastly, caregivers’ views on the practicality of using ultrasound in this developing country setting was also investigated in a qualitative survey. Results of Primary Research: The results regarding reproducibility were as follows: (i) a high between-method agreement was found in the estimation of cervical dilatation, with high ultrasound sensitivity and specificity in detecting active labour; (ii) a statistically significant between-method agreement was found in the estimation of head station, with high ultrasound sensitivity and specificity in detecting engaged fetal head; (iii) a weak between-method agreement was found in the estimation of fetal head position, with ultrasound having a higher success rate than digital VE. The results regarding acceptability showed that most mothers accepted the use of intrapartum ultrasound, and were willing to have the procedure for their future care during labour and childbirth. They also preferred ultrasound to digital VE. With regards to practicality, the responses of caregivers indicate that the introduction of intrapartum ultrasound in this setting could serve as a good complement to digital VE in a number of ways. However, putting it into practice would require wider availability of physical and technical resources. Conclusion: The findings of the reproducibility study were consistent with existing studies in other clinical settings which were investigated in the systematic review. This suggests that ultrasound is a reliable method for assessing the progress of pregnant women in labour. In addition, the unique contribution to existing knowledge obtained from this study was a high ultrasound sensitivity and specificity in detecting active labour and engaged fetal head which were reported for the first time. The findings on mothers’ acceptability were also consistent with existing studies in other settings, which is an indication that there is high acceptance of intrapartum ultrasound by mothers from different settings and cultures. Lastly, caregivers’ views on the practicality of the use of ultrasound during labour indicate that the regular use of intrapartum ultrasound for assessing the progress of labour in pregnant women may require additional resources to make it practicable in this and other similar settings.
6

Holá minulá příčestí v pre- a postpozici / Bare -ed participles as modifers

Marek, Jiří January 2021 (has links)
This thesis deals with the modification of nouns by bare past participles in the pre- and post- head positions and uses authentic examples from the written component of The British National Corpus. The aim is to describe the possibility of corpus excerption of this construction and to qualitatively compare participles in both positions using examples with context. In the first step, a simple search query was entered to retrieve bare past participles in the postnominal position with the result of 21,437 concordance lines which were then manually filtered. The resulting 14,529 lines were used to obtain a random sample of 400 lines which was again manually filtered. The resulting Sample 1 of 247 lines was described quantitatively in terms of the left and right context of the noun phrase and in terms of the head nouns. Sample 1 contained 118 unique participles, from which 10 were randomly selected for a qualitative description (Sample 2; 70 concordance lines per position, 140 lines in total). Sample 2 was then described in terms of the presence or absence of determiners, in terms of the types of definiteness, reference and restrictivity. An interesting feature is the presence of quantifiers, and the generally implied quantificational meaning of the construction. Semantics and the possibility to occur...
7

Galvos pozicijos nustatymas ekrano atžvilgiu, panaudojant ant galvos pritvirtintą kamerą / Tracking of Head Position Relative to the Screen using Head Mounted Camera

Borcovas, Evaldas 20 June 2012 (has links)
Tobulėjant kompiuteriams, ieškoma vis naujų galimybių informacijos perdavimui tarp vartotojo ir mašinos. Yra atliekama daug tyrimų žmogaus ir kompiuterio sąveikos – HCI (Human computer interaction) – srityje. Ieškoma naujų būdų bei metodų, kaip perduoti informaciją iš vartotojo kompiuteriui, ir atvirkščiai. Senesni metodai, tokie kaip įvestis pelės ir klaviatūros pagalba, išvestis vaizduoklio, projektoriaus bei spausdintuvo pagalba, yra optimizuojami. Siekiama surasti ergonomiškiausią įvesties, išvesties ir informacijos perdavimo metodą. / With the development of computers engineers are looking for new ways of commutation between user and machine. There are many researches done in human-computer interaction – HCI field. Engineers are always Ssearching for new ways, methods of transmitting information from user to machine and vice versa. Older methods, mouse and keyboard input, monitor, projector and printer output, are optimized. The aim of these studies is to find the most ergonomic input, output and communication method.
8

Facteurs influencing haptic shape perception

Toderita, Iuliana 12 1900 (has links)
Le but de cette étude était de déterminer la contribution de plusieurs facteurs (le design de la tâche, l’orientation d’angle, la position de la tête et du regard) sur la capacité des sujets à percevoir les différences de formes bidimensionnelles (2-D) en utilisant le toucher haptique. Deux séries d'expériences (n = 12 chacune) ont été effectuées. Dans tous les cas, les angles ont été explorés avec l'index du bras tendu. La première expérience a démontré que le seuil de discrimination des angles 2-D a été nettement plus élevé, 7,4°, que le seuil de catégorisation des angles 2-D, 3,9°. Ce résultat étend les travaux précédents, en montrant que la différence est présente dans les mêmes sujets testés dans des conditions identiques (connaissance des résultats, conditions d'essai visuel, l’orientation d’angle). Les résultats ont également montré que l'angle de catégorisation ne varie pas en fonction de l'orientation des angles dans l'espace (oblique, verticale). Étant donné que les angles présentés étaient tous distribués autour de 90°, ce qui peut être un cas particulier comme dans la vision, cette constatation doit être étendue à différentes gammes d'angles. Le seuil plus élevé dans la tâche de discrimination reflète probablement une exigence cognitive accrue de cette tâche en demandant aux sujets de mémoriser temporairement une représentation mentale du premier angle exploré et de la comparer avec le deuxième angle exploré. La deuxième expérience représente la suite logique d’une expérience antérieure dans laquelle on a constaté que le seuil de catégorisation est modifié avec la direction du regard, mais pas avec la position de la tête quand les angles (non visibles) sont explorés en position excentrique, 60° à la droite de la ligne médiane. Cette expérience a testé l'hypothèse que l'augmentation du seuil, quand le regard est dirigé vers l'extrême droite, pourrait refléter une action de l'attention spatiale. Les sujets ont exploré les angles situés à droite de la ligne médiane, variant systématiquement la direction du regard (loin ou vers l’angle) de même que l'emplacement d'angle (30° et 60° vers la droite). Les seuils de catégorisation n’ont démontré aucun changement parmi les conditions testées, bien que le biais (point d'égalité subjective) ait été modifié (décalage aux valeurs inférieurs à 90°). Puisque notre test avec le regard fixé à l’extrême droite (loin) n'a eu aucun effet sur le seuil, nous proposons que le facteur clé contribuant à l'augmentation du seuil vu précédemment (tête tout droit/regard à droite) doit être cette combinaison particulière de la tête/regard/angles et non l’attention spatiale. / The purpose was to determine the contribution of several factors (design of the task, angle orientation, head position and gaze) to the ability of subjects to perceive differences in twodimensional (2-D) shape using haptic touch. Two series of experiments (n=12 each) were carried out. In all cases the angles were explored with the index finger of the outstretched arm. The first experiment showed that the mean threshold for 2-D angle discrimination was significantly higher, 7.4°, than for 2-D angle categorization, 3.9°. This result extended previous work, by showing that the difference is present in the same subjects tested under identical conditions (knowledge of results, visual test conditions, angle orientation). The results also showed that angle categorization did not vary as a function of the orientation of the angles in space (oblique, upright). Given that the angles presented were all distributed around 90°, and that this may be a special case as in vision, this finding needs to be extended to different ranges of angles. The higher threshold with angle discrimination likely reflects the increased cognitive demands of this task which required subjects to temporarily store a mental representation of the first angle scanned, and to compare this to the second scanned angle. The second experiment followed up on observations that categorization thresholds are modified with gaze direction but not head position when the unseen angles are explored in an eccentric position, 60° to the right of midline. This experiment tested the hypothesis that the increased threshold when gaze was directed to the far right might reflect an action of spatial attention. Subjects explored angles located to the right of midline, systematically varying the direction of gaze (away from or to the angles) along with angle location (30° and 60° to the right). Categorization thresholds showed no change across the conditions tested, although bias (point of subjective equality) was changed (shift to lower angle values). Since our testing with far right gaze (away) had no effect on threshold, we suggest that the key factor contributing to the increased threshold seen previously (head forward/gaze right) must have been this particular combination of head/gaze/angles used and not spatial attention.
9

Facteurs influencing haptic shape perception

Toderita, Iuliana 12 1900 (has links)
Le but de cette étude était de déterminer la contribution de plusieurs facteurs (le design de la tâche, l’orientation d’angle, la position de la tête et du regard) sur la capacité des sujets à percevoir les différences de formes bidimensionnelles (2-D) en utilisant le toucher haptique. Deux séries d'expériences (n = 12 chacune) ont été effectuées. Dans tous les cas, les angles ont été explorés avec l'index du bras tendu. La première expérience a démontré que le seuil de discrimination des angles 2-D a été nettement plus élevé, 7,4°, que le seuil de catégorisation des angles 2-D, 3,9°. Ce résultat étend les travaux précédents, en montrant que la différence est présente dans les mêmes sujets testés dans des conditions identiques (connaissance des résultats, conditions d'essai visuel, l’orientation d’angle). Les résultats ont également montré que l'angle de catégorisation ne varie pas en fonction de l'orientation des angles dans l'espace (oblique, verticale). Étant donné que les angles présentés étaient tous distribués autour de 90°, ce qui peut être un cas particulier comme dans la vision, cette constatation doit être étendue à différentes gammes d'angles. Le seuil plus élevé dans la tâche de discrimination reflète probablement une exigence cognitive accrue de cette tâche en demandant aux sujets de mémoriser temporairement une représentation mentale du premier angle exploré et de la comparer avec le deuxième angle exploré. La deuxième expérience représente la suite logique d’une expérience antérieure dans laquelle on a constaté que le seuil de catégorisation est modifié avec la direction du regard, mais pas avec la position de la tête quand les angles (non visibles) sont explorés en position excentrique, 60° à la droite de la ligne médiane. Cette expérience a testé l'hypothèse que l'augmentation du seuil, quand le regard est dirigé vers l'extrême droite, pourrait refléter une action de l'attention spatiale. Les sujets ont exploré les angles situés à droite de la ligne médiane, variant systématiquement la direction du regard (loin ou vers l’angle) de même que l'emplacement d'angle (30° et 60° vers la droite). Les seuils de catégorisation n’ont démontré aucun changement parmi les conditions testées, bien que le biais (point d'égalité subjective) ait été modifié (décalage aux valeurs inférieurs à 90°). Puisque notre test avec le regard fixé à l’extrême droite (loin) n'a eu aucun effet sur le seuil, nous proposons que le facteur clé contribuant à l'augmentation du seuil vu précédemment (tête tout droit/regard à droite) doit être cette combinaison particulière de la tête/regard/angles et non l’attention spatiale. / The purpose was to determine the contribution of several factors (design of the task, angle orientation, head position and gaze) to the ability of subjects to perceive differences in twodimensional (2-D) shape using haptic touch. Two series of experiments (n=12 each) were carried out. In all cases the angles were explored with the index finger of the outstretched arm. The first experiment showed that the mean threshold for 2-D angle discrimination was significantly higher, 7.4°, than for 2-D angle categorization, 3.9°. This result extended previous work, by showing that the difference is present in the same subjects tested under identical conditions (knowledge of results, visual test conditions, angle orientation). The results also showed that angle categorization did not vary as a function of the orientation of the angles in space (oblique, upright). Given that the angles presented were all distributed around 90°, and that this may be a special case as in vision, this finding needs to be extended to different ranges of angles. The higher threshold with angle discrimination likely reflects the increased cognitive demands of this task which required subjects to temporarily store a mental representation of the first angle scanned, and to compare this to the second scanned angle. The second experiment followed up on observations that categorization thresholds are modified with gaze direction but not head position when the unseen angles are explored in an eccentric position, 60° to the right of midline. This experiment tested the hypothesis that the increased threshold when gaze was directed to the far right might reflect an action of spatial attention. Subjects explored angles located to the right of midline, systematically varying the direction of gaze (away from or to the angles) along with angle location (30° and 60° to the right). Categorization thresholds showed no change across the conditions tested, although bias (point of subjective equality) was changed (shift to lower angle values). Since our testing with far right gaze (away) had no effect on threshold, we suggest that the key factor contributing to the increased threshold seen previously (head forward/gaze right) must have been this particular combination of head/gaze/angles used and not spatial attention.
10

Závislost spotřeby dýchaného média a polohy těla na vybraném způsobu potápěčského kopu a rychlosti plavání / Dependence oftheair consumption and thepositionofthe body on theselectedmethodofdivingkick and swimming speed

Ehl, Sebastian January 2020 (has links)
Title: Dependence of the air consumption and the position of the body on the selected method of diving kick and swimming speed Objectives: The goal of this work is to find out the relationship between the diver's swimming speed and the air consumption while using two different methods of diving kicks - flutter and frog kick. At the same time, assess the dependence of the position of the body and head on the swimming speed and method of diving kicks. Methods: In this work was used method of collecting data in real conditions by measuring devices and statistical evaluation of collected data. Results: The results are presented by graphs both in the text of this work and in attachment for its large size. The results of all probands are presented in summary graphs and for selected values the degree of association is calculated in tables using the Pearson correlation coefficient. The main result is the confirmation of the reduction of the deviation from the horizontal position when comparing the slow and higher swimming speeds of both flutter and frog kick. The most effective way for a diver to overcome 50 meters below the water surface was determined to be a flutter kick at medium speed (average 0,37 m/s). Keywords: scuba diving, body position, head position, air consumption, speed of swimming, flutter...

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