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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 uniform theory of diffraction approach to determine endfire glide slope performance in the presence of ground plane irregularities

Gordon, Matthew D. January 1994 (has links)
Thesis (M.S.)--Ohio University, November, 1994. / Title from PDF t.p.
2

An airport glide-path system, using flush-mounted, traveling-wave runway antennas /

McFarland, Richard Herbert January 1962 (has links)
No description available.
3

Development of a near-zone computer model for investigation of feasibility of ground checking the capture-effect glide slope

D'Estaintot, Thierry Langlois. January 1984 (has links)
Thesis (M.S.)--Ohio University, June, 1984. / Title from PDF t.p.
4

Design of an image radiation monitor for ILS glide slope in the presence of snow

Marcum, Frank. January 1995 (has links)
Thesis (Ph. D.)--Ohio University, August, 1995. / Title from PDF t.p.
5

Analysis, design and fabrication of a frangible tower for use with sideband reference glide slope systems

Johnson, Matthew H. January 1996 (has links)
Thesis (M.S.)--Ohio University, August, 1996. / Title from PDF t.p.
6

En route speed optimization for continuous descent arrival

Lowther, Marcus Benjamin. January 2008 (has links)
Thesis (M. S.)--Aerospace Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Clarke, John-Paul; Committee Member: Barnes, Earl; Committee Member: Pritchett, Amy
7

An In Vitro comparison of three different techniques to create a glide path prior to nickel titanium rotary instrumentation

Cassim, Imran January 2013 (has links)
The preparation of a glide path prior to the use of rotary nickel titanium instrumentation reduces torsional stress and the risk of rotary nickel titanium instrument separation. The objective of this in vitro study was to evaluate 3 different glide path preparation techniques in respect of:  Percentage change of curvature from original canal anatomy; and  The occurrence of aberrations in canal anatomy (ledging, zipping and elbows). One hundred and twenty S-shaped Endo-Training-Blocks were selected. The canals were injected with India ink dye. The blocks were indexed with 3 bur marks and placed into a template before pre-instrumentation images were acquired digitally. The blocks were randomly divided into four groups of thirty each. Glide paths were prepared by a single operator with stainless steel hand K-files only, up to ISO size 20 (group 1, control), stainless steel hand K-files in the M4 reciprocating hand-piece up to ISO size 20 (group 2), hand K-files to ISO size 10 then NiTi rotary PathFiles (group 3) and hand K-files to ISO size 10 then NiTi rotary X-Plorer files (group 4). After glide path preparation the blocks were replaced into the template and post-instrumentation images were digitally acquired. Percentage change of curvature from original canal anatomy: Pre-instrumentation and post-instrumentation images were imported into Rhinoceros software to determine the end points of the canal curves and calculate the percentage change of canal curvature for the radii of apical and coronal curves. The data was collected and tabulated. Differences in canal curvature modification were statistically analysed with respect to logarithmic transformed change from baseline using ANCOVA (p<0.001) with logarithmic transformed pre-instrumentation values as covariate. After establishing preparation differences, both for change from baseline (pre-instrumentation) for apical and coronal curves, specific differences were tested using Fisher’s LSD for pairwise comparisons. Prepared groups differed significantly (p<0.001) and in particular, group 1 (Hand K-files) (control) and group 2 xiii (Hand K-files in M4 Safety reciprocating hand piece) differed significantly from all the other groups while group 3 (Hand K-files and PathFiles) and group 4 (Hand K-files and X-Plorer files) did not differ significantly. Group 3 (Hand K-files and PathFiles) and group4 (Hand K-files and X-Plorer files) were also superior to group1 (Hand K-files) (control) and group2 (Hand K-files in M4 Safety reciprocating hand piece). The occurrence of aberrations in canal anatomy (ledging, zipping and elbows): Pre-instrumentation and post-instrumentation images were superimposed using Adobe Photoshop software. The images were imported into a PowerPoint presentation and examined by three different blinded clinicians independently, for the presence of aberrations. There were no differences between the examiners in their assessment of the images. The data was collected and tabulated. The incidence of canal aberrations was analysed using Fisher’s exact test (p<0.05). The groups differed significantly regarding the number of aberrations (p=0.005). In particular, group 1 (control) (Hand K-files) and group 2 (Hand K-files in the M4 reciprocating hand piece) did not differ statistically (p=0.254; 20% and 6.67%). However group 2 (hand K-files in the M4 reciprocating hand piece) also did not differ significantly from group 3 (Hand K-files and PathFiles) and Group 4 (Hand K-files and X-Plorer files) (p=0.326). There were no aberrations detected in the rotary NiTi groups (group 3 and group 4). / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Odontology / unrestricted
8

Análise da eficácia do instrumento RECIPROC #25 em atingir o forame apical sem glide path / Analysis of the effectiveness of the instrument RECIPROC #25 to achieve the foramen without glide path

Thiane Elys Prado Arruda Cavalcante 10 February 2012 (has links)
O presente estudo avaliou a eficáciado instrumento Reciproc#25 em atingir o forame de canais de molares inferiores sem um glide path manual prévio. Para isso, uma amostra geral de 300 molares inferiores foi radiografada e previamente selecionada quanto ao grau de curvatura segundo critério de Schneider sendo divididos em classes I e II. Após a aplicação dos critérios de inclusão e exclusão, uma amostragem total de 502 canais radiculares foi incluída para formar os grupos experimentais: 253 canais no grupo de molares inferiores classe I e 249 no grupo de molares classe II. Todos os canais foram instrumentados diretamente com a lima 25, sem nenhum glide path prévio, seguindo criteriosamente as diretrizes do fabricante. Os dados foram descritos como a frequência da distribuição do número de canais (%) nos quais foi possível chegar ao forame apical sem a necessidade de glide path, assim como o número de fraturas em cada grupo. Os resultados compilados dos 2 grupos experimentais mostraram que em 93,4% do total dos canais instrumentados, o instrumento R25 foi capaz de ir até o forame apical sem a necessidade de glide path. Em 6,4% do total dos canais, o instrumento R25 não chegou até o forame apical e em somente 0,2% dos casos ocorreu fratura da lima (um caso no grupo classe I, enquanto no grupo classe II não houve nenhuma ocorrência de fratura). O teste Qui-quadrado foi realizado para verificar se uma determinada classe de canais encontra-se mais associada ou não a necessidade de glide path quando o sistema Reciproc é usado. No grupo de molares classe II houve maior número de canais (23) que o instrumento R25 não foi capaz de ir até o forame apical do que no grupo de molares classe I (9), sendo essa diferença estatisticamente significante (Qui-quadrado, p=0,020, X2=5,452). Dentro das condições experimentais do presente estudo, pode-se concluir então quea lima R25 mostrou uma alta eficácia em instrumentar toda a extensão dos canais de molares inferiores classe I e II sem a necessidade de glide path prévio. Além disso, o sistema de instrumentação proposto mostrou-se altamente seguro quanto ao índice de fratura. / The aim of the present studywas to evaluate the effectiveness of the Reciproc #25 instrument in reaching the apical foramen of mandibular molars root canals without any manual glide path. For this, a general sample of 300 mandibular molars was radiographed and graded accordantly the degree of curvature (Schneiders criteria) classes I and II. After applying the inclusion and exclusion criteria, a total of 502 root canals were included to form the two experimental groups: 253 canals in the class Igroupand 249 in the class II group. All canals were instrumented directly with R25 file, without any manual glide path, carefully following the manufactures guidelines. The pooled results of two experimental groups showed that the R25 instrument was able to reach the apical foramen without glide path in 93.4% of the cases. In 6.4%, the instrument R25 was unable to reach the apical foramen and in only 0.2% of the cases occurredinstrument fracture (one fracture in the class I group andnone in the class II group). The chi-square test was accomplished to verify that a certain class of channels is more associated with or without the need for glide path when the Reciproc system is used. . In the group of class II molar higher number of channels (23) that the instrument was not able to go to the apical foramen than in the molar class I (9), and this difference was statistically significant (Chi-square test, p = 0.020, X2 = 5.452) Within the experimental conditions of this study, it can be concluded that the file R 25 showed to be a highly effective instrument in the instrumentation of the entire length of the canals of mandibular molars class I and II without prior glide path. In addition, the instrumentation system was shown to be highly safe in the rate of fracture.
9

Análise da eficácia do instrumento RECIPROC #25 em atingir o forame apical sem glide path / Analysis of the effectiveness of the instrument RECIPROC #25 to achieve the foramen without glide path

Thiane Elys Prado Arruda Cavalcante 10 February 2012 (has links)
O presente estudo avaliou a eficáciado instrumento Reciproc#25 em atingir o forame de canais de molares inferiores sem um glide path manual prévio. Para isso, uma amostra geral de 300 molares inferiores foi radiografada e previamente selecionada quanto ao grau de curvatura segundo critério de Schneider sendo divididos em classes I e II. Após a aplicação dos critérios de inclusão e exclusão, uma amostragem total de 502 canais radiculares foi incluída para formar os grupos experimentais: 253 canais no grupo de molares inferiores classe I e 249 no grupo de molares classe II. Todos os canais foram instrumentados diretamente com a lima 25, sem nenhum glide path prévio, seguindo criteriosamente as diretrizes do fabricante. Os dados foram descritos como a frequência da distribuição do número de canais (%) nos quais foi possível chegar ao forame apical sem a necessidade de glide path, assim como o número de fraturas em cada grupo. Os resultados compilados dos 2 grupos experimentais mostraram que em 93,4% do total dos canais instrumentados, o instrumento R25 foi capaz de ir até o forame apical sem a necessidade de glide path. Em 6,4% do total dos canais, o instrumento R25 não chegou até o forame apical e em somente 0,2% dos casos ocorreu fratura da lima (um caso no grupo classe I, enquanto no grupo classe II não houve nenhuma ocorrência de fratura). O teste Qui-quadrado foi realizado para verificar se uma determinada classe de canais encontra-se mais associada ou não a necessidade de glide path quando o sistema Reciproc é usado. No grupo de molares classe II houve maior número de canais (23) que o instrumento R25 não foi capaz de ir até o forame apical do que no grupo de molares classe I (9), sendo essa diferença estatisticamente significante (Qui-quadrado, p=0,020, X2=5,452). Dentro das condições experimentais do presente estudo, pode-se concluir então quea lima R25 mostrou uma alta eficácia em instrumentar toda a extensão dos canais de molares inferiores classe I e II sem a necessidade de glide path prévio. Além disso, o sistema de instrumentação proposto mostrou-se altamente seguro quanto ao índice de fratura. / The aim of the present studywas to evaluate the effectiveness of the Reciproc #25 instrument in reaching the apical foramen of mandibular molars root canals without any manual glide path. For this, a general sample of 300 mandibular molars was radiographed and graded accordantly the degree of curvature (Schneiders criteria) classes I and II. After applying the inclusion and exclusion criteria, a total of 502 root canals were included to form the two experimental groups: 253 canals in the class Igroupand 249 in the class II group. All canals were instrumented directly with R25 file, without any manual glide path, carefully following the manufactures guidelines. The pooled results of two experimental groups showed that the R25 instrument was able to reach the apical foramen without glide path in 93.4% of the cases. In 6.4%, the instrument R25 was unable to reach the apical foramen and in only 0.2% of the cases occurredinstrument fracture (one fracture in the class I group andnone in the class II group). The chi-square test was accomplished to verify that a certain class of channels is more associated with or without the need for glide path when the Reciproc system is used. . In the group of class II molar higher number of channels (23) that the instrument was not able to go to the apical foramen than in the molar class I (9), and this difference was statistically significant (Chi-square test, p = 0.020, X2 = 5.452) Within the experimental conditions of this study, it can be concluded that the file R 25 showed to be a highly effective instrument in the instrumentation of the entire length of the canals of mandibular molars class I and II without prior glide path. In addition, the instrumentation system was shown to be highly safe in the rate of fracture.
10

Multipath limiting antenna design considerations for ground based pseudolite ranging sources

Dickman, Jeffrey. January 2001 (has links)
Thesis (M.S.)--Ohio University, November, 2001. / Title from PDF t.p.

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