Thesis (M.S.)--University of Michigan, 1969.

Thesis (M.S.)--University of Michigan, 1970.

Thesis (doctoral)--University of Hong Kong, 1988.

Over the last 20 years, Gregory G. Zilliac of the NASA AMES Research Center has been in continuous development of a fringe-imaging skin friction PC application used in oil interferometry analysis. This application, CXWIN5G, allows users to analyze propagation of oil smears across an aerodynamic surface using photogrammetry. The purpose of this thesis is to investigate the feasibility of increasing the level of automation currently found in CXWIN5G by developing a MATLAB solver capable of determining oil smear geometry with minimal user input. There are two main automation goals of this thesis that are reflected in the core of the MATLAB solver: the determination of oil smear centerline propagation without user input and the calculation of fringe spacing without the use of fiduciary markings on the test surface. In CXWIN5G, oil smear propagation centerlines must be drawn by a user with their computer mouse. The MATLAB solver removes the necessity for this by utilizing the centroid location of each fringe as a reference for centerline propagation. The solver’s ability to calculate fringe spacing without the use of fiduciary markings is a result of its ability to accurately determine the physical dimensions captured in an image. This is done by separating the camera’s field of view into its pixel components and calculating the horizontal and vertical object length captured in each pixel. Validation of the MATLAB solver’s ability to define fringe propagation and fringe spacing is performed at multiple different camera positions. When the camera location is not directly overhead an oil smear the camera is in a state of skew. Camera skew is measured in degrees, and can occur in the horizontal or vertical direction. Images analyzed in this thesis feature representative hand-drawn oil smears, as well as oil smears created in the Cal Poly 3’ x 4’ low speed wind tunnel. The MATLAB solver’s ability to create accurate centerlines is accessed by comparing pixel coordinates of the MATLAB centerlines with pixel coordinates of centerlines created on an identical image in Microsoft Paint. During experimentation, 18 images were analyzed under both horizontal (X) and vertical (Y) skew camera conditions, with skew angles ranging from zero to 13.2 degrees. Under X-skew camera conditions the average position error between MATLAB and hand drawn centerlines is 0.6 %, while average position error under Y-skew camera conditions is 1.0 %. Fringe spacing accuracy is defined by how closely fringe spacing determined by the MATLAB solver is to fringe spacing measured by hand with a 1/16th inch ruler. Spacing analysis is performed on the same photos used in centerline determination. For X-skew camera positions, the average fringe spacing error is 6.1 %, while the average spacing error in Y-skew conditions is 4.3 %. As is discussed in later sections of this text, the X-skew fringe spacing error is artificially inflated due to human error during data collection.

No description available.

No description available.

Call number: LD2668 .T4 1956 D45 / Master of Science

A dissertation submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of master of Science in Engineering. / A software package was written under the X Window System, Version 11, to assist in manual stereopsis of multiple views. The package enables multiple high resolution (2000 by 1500 pixels and higher) black and white photographs to be viewed simultaneously. Images have adjustable zoom windows which can be manipulated with the pointing device. The zoom windows enlarge to many times the resolution of the image enabling sub-pixel measurements to be extrapolated by the operator. A user-friendly interface allows for fast pinhole camera calibration (from known 3D calibration points) and enables three dimensional lines, circles, grids, cylinders and planes to be fitted to markers specified by the user. These geometric objects are automatically rendered in 3D for comparison with the images. The camera calibration is performed using an iterative optimisation algorithm which also tries multiple combinations of omitted calibration points. This allows for some fault tolerance of the algorithm with respect to erroneous calibration points. Vector mathematics for the geometrical fits is derived. The calibration is shown to converge on a variety of photographs from actual plant surveys. In an artificial test on an array of constructed 3D coordinate markers, absolute accuracy was found to be 1 mm (standard deviation of the Euclidean error) for a distance of 2.5 meters from a standard 35 mm camera. This translates to an error of 1.6 pixels in the scanned views. Lens distortion was assumed to be negligible, except for aspect ratio distortion which was calibrated for. Finally. to demonstrate the efficacy of the package, a 3D model was reconstructed from ten photographs of a human face, taken from different angles. / AC2017

A influência das alterações posturais na produção da voz é um assunto bastante interessante e de grande importância para aqueles que utilizam a voz profissionalmente. O objetivo do presente estudo é identificar a influência no sinal vocal de um mesmo indivíduo quando este muda sua postura corporal. Foram realizadas as análises de 25 amostras vocais de um indivíduo que emitiu a vogal sustentada /a/ em três diferentes posturas corporais: A) ortostática natural do sujeito; B) anteriorização da cabeça associada com extensão da coluna cervical; e C) aumento da cifose torácica associada com anteriorização de cabeça. O indivíduo foi fotografado simultaneamente ao processo de gravação da voz. As posturas foram avaliadas por fotogrametria pelo programa Corel Draw 10. A voz foi analisada por análise acústica por meio do programa MDVP inserido no software Multi Speech 3700 da Kay Elemetric Corporation e pela avaliação perceptivo-auditiva da voz. O resultado comparativo entre as amostras vocais nas posturas A e B foi significante, na análise acústica, na variável e jitter (%); e na avaliação perceptivo-auditiva, as diferenças observadas foram referentes à qualidade vocal, à ressonância e ao pitch, que se tornou mais agudo em 56% das amostras. Na comparação das posturas A e C, não houve resultado significativo na análise acústica; e na avaliação perceptivo-auditiva as mudanças percebidas foram referentes à qualidade vocal, à ressonância e ao pitch, que se tornou mais agudo em 60% das amostras. Conclusão: as diferenças observadas na comparação das posturas A e B foram: aumento do valor médio de jitter; aumento do pitch; ressonância se tornou posterior e abafada; e piora na qualidade vocal. As diferenças observadas na comparação das posturas A e C foram: aumento do pitch; ressonância se tornou comprimida; e piora na qualidade vocal. / The influence of the different corporal postures in the voice production is a very interesting subject and it\'s very important for those who use their voice professionally. The aim of the present investigation is to identify the influence in the voice signal of the same subject whenever he changes his corporal posture. It was made the analysis of 25 vocal samples of one subject who emitted the vocal sustained /a/ in three different corporal postures: A) normal alignment of the subject; B) cervical spine extension associated with forward head position; and C) increased thoracic kyphosis associated with forward head position. The subject was photographed simultaneously of the recording process. The postures were evaluated by photogrammetry by the Corel Draw 10 program. The voice was analyzed by acoustic analysis by the MDVP program inserted in the Multi Speech 3700 software from Kay Elemetric Corporation and by perceptual speech analysis. The comparative result between the voices samples in the postures A and B was significant, to the acoustic analysis, to the variable jitter (%); and to the perceptual speech analysis, the differences observed were related to vocal quality, resonance and pitch, which turned out to be more acute in 56% of the samples. In the comparison of the postures A and C, there wasn\'t significant result in the acoustic analysis; and to the perceptual speech analysis the changes noticed were related to vocal quality, resonance and pitch, which turned out to be more acute in 60% of the samples. Conclusion: the differences observed on the comparison of the postures A and B were: jitter medium value increased; pitch increased; resonance turned out to be posterior and muffled; and worse voice quality. The differences observed on the comparison of the postures A and C were: pitch increased; resonance turned out to be compressed; and worse voice quality.

Durante a infância e a adolescência, ocorrem várias mudanças posturais, em função dos ajustes necessários para a estruturação e definição da postura. A postura sofre mudanças por causa da influência hormonal que ocorre com o início da puberdade e com o crescimento musculoesquelético. Sendo assim, as fases pré puberal e puberal, são cruciais para o desenvolvimento de uma boa postura. Além disso, alterações de sobrecarga durante esta fase, podem interferi no desempenho do aparelho locomotor. Dentre os fatores, que influenciam essas variáveis, está o uso dos calçados de salto alto que vêm se tornando cada vez mais precoce e freqüente nesta população. O objetivo, deste estudo foi avaliar a influência dos calçados de salto alto na postura e na marcha de adolescentes ente 13 a 20 de idade. Foi realizado com adolescentes do sexo feminino, para o estudo postural e impressão plantar avaliadamos 50 adolescentes do grupo não usuárias (GNU) de calçados de salto alto e 50 do grupo usuárias (GU). O estudo postural foi feito por fotografias nas condições descalça e com salto anabella e analisadas pelo software SAPO. Os ângulos medidos foram: lordose lombar, alinhamento horizontal da pelve, ângulo do joelho, ângulo tíbio társico, ângulo frontal do membro inferior direito (D) e esquerdo (E), ângulo Q (D) e (E) e ângulo do retropé (D) e (E). Através da impressão plantar analisamos o Índice de Chippaux-Smirak. O estudo da marcha foi realizado com 11 adolescentes no GNU e 9 do GU. Através da plataforma de força analisamos a força reação do solo nas condições descalça e com o salto. Os dados foram submetidos a análises descritivas. Foi adotado um nível de significância de 5%. Na comparação entre as condições, encontramos com o uso do salto no GNU: retificação lombar, retroversão pélvica, aumento do ângulo tíbio-társico, aumento do valgo de joelhos e patelar e varo de retropé. Já para GU, encontramos as mesmas modificações que no GNU, porém com variações diferentes e com exceção apenas para o ângulo lombar que apresentou hiperlordose e ângulo pélvico com anterversão. Na comparação entre os grupos, observamos na condição descalça que o GU apresentou menor ângulo da lordose lombar, maior anteversão, menor ângulo tíbio társico, maior valgismo de joelho e patela. Já na condição com o salto o GU apresentou o ângulo de lordose lombar menor, ângulo pélvico com postura inversa ao do GNU, acentuação do valgismo patelar que manteve os grupos diferentes e embora ambos tenham apresentado varo de retropé, o GU mostrou um valor maior. O arco longitudinal se mostrou diferente com valores menores para o GU e classificadas com pés normais enquanto que o GNU foi classificado com pés intermediários. Na marcha, o tempo de apoio total e menor força vertical na comparação entre os dois grupos se apresentaram menor para GU nas duas condições. A taxa de crescimento do segundo pico foi maior na condição descalça para GU e a taxa de crescimento do pico passivo foi maior na condição descalça em ambos os grupos. A variável pico passivo apresentou-se em ambos os grupos nas duas condições. Concluímos que o calçado de salto rígido influenciou de forma significante os ângulos posturais, tanto na observação aguda no GNU, como na observação de uso crônico como no GU, assim como, observado no arco plantar e em algumas variáveis da força reação do solo vertical. / During childhood and adolescence, there are several posture changes depending on the settings necessary for the structuring and definition of posture. The posture change because of the hormonal influence that occurs with the onset of puberty and the musculoskeletal growth. Thus, the pre pubertal and pubertal stages are crucial for the development of good posture. Moreover, changes of overload during this phase, may interfere with the performance of the locomotor system. Among the factors that influence these variables, is the use of high-heeled shoes that are becoming increasingly early and frequent in this population. The objective of this study was to evaluate the influence of high-heeled shoes in posture and pace of adolescents between 13 to 20 of age. Was conducted with female adolescents in the study posture and printing plant of the group evaluated 50 adolescents not using (GNU) of high-heeled shoes and 50 of the group users (GU). The study was done by photos at the postural conditions barefoot and Anabella heeland analyzed by software SAPO. The angles were measured: lumbar lordosis, horizontal alignment of the pelvis, knee angle, tepid-tarsus angle, frontal angle of the right lower limb (D) and left (E), angle Q (D) and (E) and angle of the hindfoot ( D) and (E). By printing plant we analyzed the index of Chippaux-Smirak. The study of the march was conducted with 11 adolescents in the GNU and 9 of GU. Through the platform of force to analyze the ground reaction force in accordance with the barefoot and with the heel. The data were submitted to descriptive analysis. Was adopted a significance level of 5%. In the comparison between conditions, we find with the heel using in the GNU: lumbar adjustment, pelvic retroversion, increase of the tepid-tarsus angle, increase in the valgus knees and patellar varus and hindfoot of. For GU, we find the same changes as in GNU, but with different variations and except only for the lumbar angle that showed hyperlordosis and pelvic angle with anterversion. In the comparison between groups, we observed in the barefoot condition that the GU had smaller angle of lumbar lordosis, increased anteversion, lower tepid-tarsus angle, more the knee and patella valgus. Already provided with the heel, GU had a lower lumbar lordosis angle, pelvic angle with the inverse posture of the GNU, stress of the patellar valgus that kept the difference between the groups and although both have made the hindfoot varus, the GU has a higher value. The longitudinal arch was different with lower values for the GU and classified with normal feet while GNU was classified with intermediaries feet. In pace, the time of support and lower total vertical force in the comparison between the two groups presented lower for GU in the two conditions. The growth rate of the second peak was higher in the barefoot condition for GU and the growth rate peak was higher in the passive condition barefoot in both groups. The variable peak liabilities is presented in both groups in both conditions. We conclude that the footwear heel hard to significantly influence the postural angles, both in acute observation in GNU, and the observation of chronic use as in GU, as well as observed in the plantar arch and some variables of the vertical ground reaction force.