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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

A study of in-situ stress magnitudes in the North Sea basin from borehole measurements

Edwards, Stephen Tean January 1998 (has links)
No description available.
2

A three-colour photometric survey of Virgo 'core' lenticular galaxies

Malcolm, Gordon J. January 1987 (has links)
Photographic Surface photometry in the Johnson B, R and I passbands of eighteen galaxies within 3° of the Virgo cluster 'core' is presented in this work. U.K. National facilities and STARLIKK common-user software were used to produce major and minor-axis luminosity profiles, colour-difference profiles, isophotal maps, equivalent profiles, and standard luminosity parameters for each galaxy in each passband. Standard techniques have been applied to the equivalent profiles to produce decomposed bulge and disk components for each galaxy. Solutions which are demonstrated to be realistic representations of the programme galaxies are amalgamated with previously-published independent data to construct homogeneous data sets. Nearly all the lenticular systems surveyed display vestigial disk structure or unusual features in the colour-difference profiles. Statistical analysis of the constructed data sets reveals no significant structural differences in the bulge components of disk systems as a function of morphological type, in contradiction with the earlier results of Dressier (1980). Significant differences in the disk components as a function of morphological type are found in the B-band data, but not the I-band data, in agreement with the results of Hamabe (1982) and Boroson et al. (1983b) respectively. The primary objections to the production of lenticular galaxies from spiral progenitors appear to have been discredited, together with several intrinsic-formation theories, and the results presented in this survey are considered strongly supportive of the hypothesis of a common origin of disk systems of all morphological types. The conclusion that at least some fraction of lenticular systems must have looked like spiral galaxies at some time in their history seems almost inescapable.
3

A preferência pela prática de atividades físicas e esportivas: uma abordagem psicofísica / The preference for the practice of physical and sporting activities: an psychophysical analysis

Ferraz, Marcelo Antonio 21 November 2005 (has links)
A preferência pela prática de atividades físicas e esportivas é um atributo subjetivo de difícil mensuração e que tem sido um dos critérios fundamentais, na escolha e na decisão para a sua prática, nos dias atuais. Deste modo, a preferência pela prática de atividades físicas e esportivas foi investigada por meio de métodos psicofísicos escalares diretos e indiretos e, conseqüentemente, escalas de razão, escalas intervalares e escalas ordinais foram comparadas. Os objetivos secundários foram verificar se este contínuo subjetivo possui características protéticas ou metatéticas, verificar se os princípios da Lei de Ekman é valida também para este contínuo subjetivo e identificar diferenças no julgamento da preferência de homens e mulheres. Três experimentos foram realizados. No primeiro experimento participaram vinte sujeitos, dez homens e dez mulheres entre 20 e 25 anos de idade, graduandos que não pertencem ao curso superior de Educação Física. Todos os sujeitos foram submetidos a uma avaliação prévia, que constou do julgamento em testes psicofísicos: a) Teste de estimação de magnitudes (com módulo) e b) Teste de estimação em categorias 1-7. No segundo experimento participaram outros vinte sujeitos, sendo respeitada a mesma divisão do primeiro experimento com relação ao gênero, a idade e a não vinculação com o curso de Educação Física. Os testes deste experimento foram: a) Teste de emparelhamento intermodal com as modalidades de comprimento de linhas e b) Teste de estimação de magnitudes (com módulo). No terceiro experimento participaram quarenta sujeitos, sendo vinte homens e vinte mulheres entre 20 e 25 anos de idade Os testes deste experimento foram: a) Teste de comparação aos pares e b) Teste de estimação de magnitudes (com módulo). Os resultados indicaram que a atividade física de Caminhada foi a atividade de maior preferência, seguida pelos esportes coletivos de Voleibol e Futebol, por outro lado, a atividade física de Remo estacionário obteve a menor preferência, seguida pelas atividades físicas de Dardos (na parede) e do esporte Judô. As demais atividades foram escalonadas de modo intermediário pelos sujeitos. Nos julgamentos dos participantes masculinos as atividades de menor preferência foram: Remo Estacionário, Tênis (simples) e Dardos (na parede), já para as participantes femininas foram os esportes Judô, Remo Estacionário e Dardos. Com as atividades de maior preferência, os sujeitos masculinos apontaram o Futebol, a Caminhada e a Inatividade e os sujeitos do sexo feminino indicaram a Caminhada, o Voleibol e a Hidroginástica. As ordenações resultantes dos métodos produzem posições de preferência altamente concordantes. Os participantes mensuraram razões e não apenas diferenças, portanto, o contínuo subjetivo avaliado possui características protéticas. O teste de emparelhamento intermodal apontou uma alta correlação entre as estimativas de comprimentos de linhas com as estimativas numéricas de magnitudes, indicando a validade da escala de razão. A variabilidade das estimativas foi uma função linear das estimativas de magnitudes, confirmando os princípios da Lei de Ekman, também para este contínuo subjetivo. Independente do método psicofísico utilizado, tanto homens quanto mulheres apresentaram consistência nos seus julgamentos. Os resultados fornecem uma escala de preferência, em nível de mensuração de razão, que é válida, estável e consistente. / The preference for practicing physical and sporting activities is a subject attribute that is difficult to be measured and it has been one of the fundamental approaches, in the choice and in the decision for its practice, in the current days. This way, the preference for practicing physical and sporting activities was investigated through psychophysical methods in direct and indirect scales, and consequently, ratio scales, interval scales and ordinal scales were compared. The secondary objectives were to check if this social continuous has prothetic or metathetic characteristics, cheking if the fundaments of Ekman Law has been worth for this social continuous and identify differences in the judgments from men and women?s preferences. Three experiments were accomplished. In the first experiment there were twenty participants, there were ten men and ten women among 20 to 25 years old, graduating students but not from Physical Education. All the participants were submitted to a previous evaluation, that consisted from the judgments in psychophysical tests: a) Test of magnitudes estimation (with module) and b) Test of categories estimation 1-7. In the second experiment there were other twenty participants, respecting the same division from the first experiment in relation to gender, age, and non-link to the Physical Education course. The tests of these experiments were: a) Test of cross-modality matches with the modalities of line?s length and b) Test of magnitude estimation (with module). In the third experiment there were forty participants, twenty men and twenty women among the age of 20 to 25 years. The tests of these experiments were: a) Comparison test in pairs and b) Test of magnitude estimation (with module). The results indicated that the physical activity of Walking was the most preferred, followed by collective sports as Volleyball and Soccer; on other hand, the physical activity of Stationary Row obtained the least preference, followed by the physical activities of Darts (on the wall) and Judo. The other activities were in scaled by the participants in an intermediate way. In men?s judgments the least preferred activities were: Stationary Row, Tennis (simple) and Darts (on the wall). To women?s judgments they were Judo, Stationary Row and Darts. The most preferred that men aimed were Soccer, Walking and the Inactivity. To women were Walking, Volleyball and Water Aerobic. The orderings results from the methods produce preference positions highly related. The participants measured ration and not only differences, so the social continuous appraised has prothetic characteristics. The test of cross-modality matches aimed a high correlation between the lengths estimate of line with the numeric magnitudes estimation, indicating the validity of the ratio scale. The variability of the estimates was a lineal function of the magnitudes estimation, confirming the fundaments of Ekman Law, also for this social continuous. Independent of the psychophysical method used, as men as women presented consistency in their judgments. The results supply a preference scale, in level of ratio measurements, which is valid, stable and consistent.
4

Magnitudes in the human brain : independent processing of time, space and number / Les magnitudes dans le cerveau humain : traitement indépendant du temps, de l'espace et des nombres

Martin, Benoît 09 October 2017 (has links)
Si vous voulez prendre votre train à l'heure, vous devez estimer à quelle distance se trouve la gare et combien de temps vous allez mettre pour y aller. Plusieurs études ont montré qu'il existe des interactions dans la perception de différentes dimensions. En 2003, Walsh a suggéré que le Temps, l'Espace et les Nombres faisaient partie d'un système de magnitudes commun qui serait localisé dans le cortex pariétal. Dans cette thèse nous avons étudié l'existence d'un tel système. La manipulation de la magnitude de dimensions non-temporelles n'a pas interféré avec les jugements de durée. En revanche, l'estimation du nombre et de l'espace a été biaisée par le taux d'accumulation d'évidence sensorielle. Dans une première expérience nous avons cherché à savoir si un système de magnitudes basé sur des probabilités Bayesiennes nécessitait l'utilisation d'un " prior " unique, amodal, ou alors nécessitait plusieurs " priors ". D'un point de vue Bayesien, nos résultats indiquent que l'estimation de différentes dimensions requiert plusieurs " priors ", ce qui ne supporte pas l'existence d'un système de magnitude commun. Pour étudier l'effet du nombre sur l'estimation de la durée, nous avons effectué une seconde étude dans laquelle les participants devaient reproduire des intervalles de temps et également juger la valeur numérique du stimulus visuel. Les résultats ont montré que l'interaction temps-nombre dépend essentiellement du format numérique utilisé (symbolique ou non symbolique). Ces résultats suggèrent que la magnitude numérique est automatiquement traitée alors que des ressources attentionnelles sont requises lorsque l'information numérique est présentée symboliquement. / If you want to catch your train on time you have to estimate how far the station is from your current position and how long it will take you to go there. A growing body of evidence suggests that interferences may exist in the perception of different magnitude dimensions. These relationships fascinate researchers for decades and led Walsh (2003) to hypothesize that Time, Space and Number were part of a generalized magnitude system which may be located in the parietal cortex. In this thesis, we first investigated the possible existence of such system. Manipulating non-temporal magnitude dimensions did not interfere with duration judgments. Instead, numerical and spatial estimates were biased when we manipulated the rate of accumulation of sensory evidence. In this first experiment we asked whether a generalized Bayesian magnitude estimation system would sample evidence using a common, amodal prior, as expected by a generalized magnitude system. Our results suggested that from a Bayesian perspective, computations would necessitate multiple priors. This work provides substantial evidence against the existence of a generalized magnitude system. To further investigate interferences of numerical magnitude on perceived duration, we built a second experiment in which participants were required to reproduce intervals of time and also judge the numerical magnitude of the stimulus. Our results revealed that the number-time interaction depended on the numerical format that was used. Our work suggests that the numerical magnitude is automatically processed at a non-symbolic level whereas it requires attentional resources when numerical information is symbolically conveyed.
5

A preferência pela prática de atividades físicas e esportivas: uma abordagem psicofísica / The preference for the practice of physical and sporting activities: an psychophysical analysis

Marcelo Antonio Ferraz 21 November 2005 (has links)
A preferência pela prática de atividades físicas e esportivas é um atributo subjetivo de difícil mensuração e que tem sido um dos critérios fundamentais, na escolha e na decisão para a sua prática, nos dias atuais. Deste modo, a preferência pela prática de atividades físicas e esportivas foi investigada por meio de métodos psicofísicos escalares diretos e indiretos e, conseqüentemente, escalas de razão, escalas intervalares e escalas ordinais foram comparadas. Os objetivos secundários foram verificar se este contínuo subjetivo possui características protéticas ou metatéticas, verificar se os princípios da Lei de Ekman é valida também para este contínuo subjetivo e identificar diferenças no julgamento da preferência de homens e mulheres. Três experimentos foram realizados. No primeiro experimento participaram vinte sujeitos, dez homens e dez mulheres entre 20 e 25 anos de idade, graduandos que não pertencem ao curso superior de Educação Física. Todos os sujeitos foram submetidos a uma avaliação prévia, que constou do julgamento em testes psicofísicos: a) Teste de estimação de magnitudes (com módulo) e b) Teste de estimação em categorias 1-7. No segundo experimento participaram outros vinte sujeitos, sendo respeitada a mesma divisão do primeiro experimento com relação ao gênero, a idade e a não vinculação com o curso de Educação Física. Os testes deste experimento foram: a) Teste de emparelhamento intermodal com as modalidades de comprimento de linhas e b) Teste de estimação de magnitudes (com módulo). No terceiro experimento participaram quarenta sujeitos, sendo vinte homens e vinte mulheres entre 20 e 25 anos de idade Os testes deste experimento foram: a) Teste de comparação aos pares e b) Teste de estimação de magnitudes (com módulo). Os resultados indicaram que a atividade física de Caminhada foi a atividade de maior preferência, seguida pelos esportes coletivos de Voleibol e Futebol, por outro lado, a atividade física de Remo estacionário obteve a menor preferência, seguida pelas atividades físicas de Dardos (na parede) e do esporte Judô. As demais atividades foram escalonadas de modo intermediário pelos sujeitos. Nos julgamentos dos participantes masculinos as atividades de menor preferência foram: Remo Estacionário, Tênis (simples) e Dardos (na parede), já para as participantes femininas foram os esportes Judô, Remo Estacionário e Dardos. Com as atividades de maior preferência, os sujeitos masculinos apontaram o Futebol, a Caminhada e a Inatividade e os sujeitos do sexo feminino indicaram a Caminhada, o Voleibol e a Hidroginástica. As ordenações resultantes dos métodos produzem posições de preferência altamente concordantes. Os participantes mensuraram razões e não apenas diferenças, portanto, o contínuo subjetivo avaliado possui características protéticas. O teste de emparelhamento intermodal apontou uma alta correlação entre as estimativas de comprimentos de linhas com as estimativas numéricas de magnitudes, indicando a validade da escala de razão. A variabilidade das estimativas foi uma função linear das estimativas de magnitudes, confirmando os princípios da Lei de Ekman, também para este contínuo subjetivo. Independente do método psicofísico utilizado, tanto homens quanto mulheres apresentaram consistência nos seus julgamentos. Os resultados fornecem uma escala de preferência, em nível de mensuração de razão, que é válida, estável e consistente. / The preference for practicing physical and sporting activities is a subject attribute that is difficult to be measured and it has been one of the fundamental approaches, in the choice and in the decision for its practice, in the current days. This way, the preference for practicing physical and sporting activities was investigated through psychophysical methods in direct and indirect scales, and consequently, ratio scales, interval scales and ordinal scales were compared. The secondary objectives were to check if this social continuous has prothetic or metathetic characteristics, cheking if the fundaments of Ekman Law has been worth for this social continuous and identify differences in the judgments from men and women?s preferences. Three experiments were accomplished. In the first experiment there were twenty participants, there were ten men and ten women among 20 to 25 years old, graduating students but not from Physical Education. All the participants were submitted to a previous evaluation, that consisted from the judgments in psychophysical tests: a) Test of magnitudes estimation (with module) and b) Test of categories estimation 1-7. In the second experiment there were other twenty participants, respecting the same division from the first experiment in relation to gender, age, and non-link to the Physical Education course. The tests of these experiments were: a) Test of cross-modality matches with the modalities of line?s length and b) Test of magnitude estimation (with module). In the third experiment there were forty participants, twenty men and twenty women among the age of 20 to 25 years. The tests of these experiments were: a) Comparison test in pairs and b) Test of magnitude estimation (with module). The results indicated that the physical activity of Walking was the most preferred, followed by collective sports as Volleyball and Soccer; on other hand, the physical activity of Stationary Row obtained the least preference, followed by the physical activities of Darts (on the wall) and Judo. The other activities were in scaled by the participants in an intermediate way. In men?s judgments the least preferred activities were: Stationary Row, Tennis (simple) and Darts (on the wall). To women?s judgments they were Judo, Stationary Row and Darts. The most preferred that men aimed were Soccer, Walking and the Inactivity. To women were Walking, Volleyball and Water Aerobic. The orderings results from the methods produce preference positions highly related. The participants measured ration and not only differences, so the social continuous appraised has prothetic characteristics. The test of cross-modality matches aimed a high correlation between the lengths estimate of line with the numeric magnitudes estimation, indicating the validity of the ratio scale. The variability of the estimates was a lineal function of the magnitudes estimation, confirming the fundaments of Ekman Law, also for this social continuous. Independent of the psychophysical method used, as men as women presented consistency in their judgments. The results supply a preference scale, in level of ratio measurements, which is valid, stable and consistent.
6

Photometric parallaxes and subdwarf identification for M-type stars

Thompson, Dayna L. 21 July 2012 (has links)
Photometric data on the Kron-Cousins photometric system have been obtained for 118 new late K to middle M-type stars with known distances. These data have been used to obtain absolute red magnitudes, to construct a color-magnitude diagram, and to compute a polynomial function for disk dwarf stars in the color range 1.5 ≤ R-I < 2.0, which can be used to compute absolute red magnitudes to be used for photometric parallaxes. Such photometric parallaxes allow new stellar distance estimations that are essential when modeling the spatial distribution of stars in our Galaxy. This is especially important for M-type stars, as they make up more than half of the mass of the Milky Way. Intermediate-band CaH observations have also been obtained in an ongoing effort to distinguish stellar luminosity classes and populations; R-L and R-I colors are used to identify possible subdwarf stars. A total of seven possible new subdwarfs and three previously known subdwarfs have been identified with this method. / Department of Physics and Astronomy
7

Event, Duration, Soul: A Study of the Measure of Intensive Magnitudes

August, John W 01 December 2018 (has links)
The treatment of intensive magnitude in Kant’s first Critique initiates a new standard for reasoning. In the dissertation, I trace the development of the concept of intensive magnitudes from Kant, through the interpretations of the physicist Gustav Fechner, and into a kind of fruition in the thought of Bergson. I illustrate how and why the concept of intensive magnitude was transformed from a spatial notion, relying primarily on sense data, in the works of Kant and Fechner into a temporalized understanding of intensity founded upon Bergson's idea of duration, where the latter is based primarily on feeling. The result of this transformation is found in the promise of creating a technical language for philosophy that is capable of appreciating the concrete unfolding of non-sensuous intensive magnitudes. Such a language renders us capable of meaningful research, conversation, and further development in understanding (at least) human becoming and its relation to time. I argue that the capacity for self-knowledge depends upon an understanding of temporality that accords with the experience of temporality itself. The development of the concept of intensity, through further philosophical reflection and inquiry, is a path philosophers should pursue.
8

From Magnitudes to Math: Developmental Precursors of Quantitative Reasoning

Starr, Ariel January 2015 (has links)
<p>The uniquely human mathematical mind sets us apart from all other animals. Although humans typically think about number symbolically, we also possess nonverbal representations of quantity that are present at birth and shared with many other animal species. These primitive numerical representations are thought to arise from an evolutionarily ancient system termed the Approximate Number System (ANS). The present dissertation aims to determine how these preverbal representations of quantity may serve as the foundation for more complex quantitative reasoning abilities. To this end, the five studies contained herein investigate the relations between representations of number, representations of other magnitude dimensions, and symbolic math proficiency in infants, children, and adults. The first empirical study, described in Chapter 2, investigated whether infants engage the ANS to represent the full range of natural numbers. The study presented in Chapter 3 compared infants' acuity for detecting changes in contour length to their acuity for detecting changes in number to assess whether representations of continuous quantities are primary to representations of number in infancy. The study presented in Chapter 4 compared individual differences in acuity for number, line length, and brightness in children and adults to determine how the relations between these magnitudes may change over development. Chapter 5 contains a longitudinal study investigating the relation between preverbal number sense in infancy and symbolic math abilities in preschool-aged children. Finally, the study presented in Chapter 6 investigated the mechanisms underlying the maturation of the number sense and determined which features of the number sense are predictive of symbolic math skill. Taken together, these findings confirm that number is a salient feature of the environment for infants and young children and suggest that approximate number representations are fundamental for the acquisition of symbolic math.</p> / Dissertation
9

Place et rôle des grandeurs dans la construction des domaines mathématiques numérique, fonctionnel et géométrique et de leurs interrelations dans l'enseignement au collège en France / The place and role of magnitudes in the development of different mathematics fields numeric, functional and geometric and in their interrelations at school in France

Anwandter-Cuellar, Nathalie 25 May 2012 (has links)
Cette recherche propose d'étudier la place et le rôle des grandeurs dans la construction des différents domaines mathématiques et de leurs interrelations au collège. Elle s'inscrit dans le cadre de la théorie anthropologique du didactique développée par Yves Chevallard. Une analyse épistémologique des savoirs mathématiques relatifs aux grandeurs nous a permis d'examiner les choix institutionnels et leurs effets sur l'enseignement. Nous complétons ce travail par une étude écologique et praxéologique des programmes, et des documents institutionnels actuels pour caractériser les rapports institutionnels aux grandeurs. Une méthodologie du type clinique est mise en œuvre pour analyser le savoir enseigné concernant les grandeurs dans des classes de 6e et 5e en France. Pour cette étude, nous nous sommes inspirés des travaux de Bronner à propos du numérique pour élaborer un outil, le filtre des grandeurs, qui sert à décrire et analyser les pratiques relatives aux grandeurs au collège. Plus particulièrement, nous nous sommes intéressés aux interrelations entre les grandeurs, le fonctionnel et le numérique en prenant le cas de la proportionnalité, et au fonctionnement interne des grandeurs en étudiant l'espèce de grandeur aire.La recherche met en évidence que l'introduction des grandeurs en tant que domaine d'étude dans les programmes du collège de 2005 crée chez les professeurs des difficultés dans l'intégration des nouvelles technologies et théories pour un enseignement adéquat des grandeurs. De plus, elle montre une certaine stabilisation de la place et la fonction des grandeurs dans la construction d'autres domaines mathématiques, mais met en évidence des difficultés au niveau des interrelations entre ces domaines. / This research aims at studying the place and role of magnitudes in the development of different mathematics fields and in their interrelations at school. Our perspective is that of the Anthropological Theory of the Didactic developed by Yves Chevallard. An epistemological analysis of the mathematical knowledge related to magnitudes allowed us to examine certain institutional choices and their impact on teaching. This work is complemented by an ecological and praxeological study of the curricula, school textbooks and corporate documents to characterize the institutions' relations to magnitudes. A clinical type methodology was used to analyze the knowledge concerning magnitudes taught in grade 6 and 7 in France. This study was inspired by Bronner's work about the numeric to develop a tool - a magnitudes filter - which is used to describe and analyze the practices related to magnitudes at school. In particular, this research focused on the interrelations between the magnitudes, the functional and the numeric in the case of proportionality and on the internal functioning of magnitudes in the case of the area magnitude.As a result, this research shows that the introduction of magnitudes as a study domain in school programs of 2005 creates difficulties among professors in integrating new technologies and theories for an adequate teaching of magnitudes. Moreover, it shows a certain stabilization of the place and role of magnitudes in the development of different mathematics fields, but difficulties concerning the interrelations between these areas.
10

Desigualdades geométricas relativas

Cerdán Sala, Ana África 04 November 2005 (has links)
No description available.

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