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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.
101

Estudo do desempenho no salto de duas espécies de Scinax de Botucatu (Amphibia, Anura, Hylidae) /

Shimizu, Renata Duarte. January 2009 (has links)
Orientador: Jorge Jim / Banca: Fernando Ribeiro Gomes / Banca: Rosângela Aparecida Marques Martinez / Resumo: O presente trabalho teve como objetivo estudar a relação entre o desempenho do salto, a morfologia e o habitat ocupado por Scinax hiemalis e S. similis (Amphibia. Anura) da região de Botucatu. Os exemplares testados foram coligidos no Recanto Ecológico Sacae-Watanabe e na Fazenda Experimental Lageado. Os testes foram realizados no laboratório e no campo, sempre após as 18:00h. Os exemplares foram testados na sala do Departamento de Zoologia, em uma pista retangular construída com base nos trabalhos de Zug (1972 e 1978). A pista é constituída de uma superfície de 1,0m de largura por 2,75m de comprimento, delimitada por duas paredes de 1,0m de altura, com a extremidade final fechada. O chão da pista foi coberto com papel de embrulho para marcação da distância do salto de cada indivíduo. Os resultados obtidos demonstraram que não há relação significativa entre as medidas dos membros posteriores e a distância do salto. Verificou-se também que não há relação entre o comprimento rostro-cloacal (CRC) e a distância do salto. Houve diferença no comportamento apresentado pelos animais das duas espécies, com S. similis demonstrando ser mais ativa e saltando quando se sentia ameaçada, enquanto S. hiemalis saltava quando tocada pela língua do predador. No campo os exemplares de S. hiemalis saltaram pouco e os saltos foram geralmente curtos, provavelmente devido ao ambiente que habitam (mata) e ao padrão de coloração críptica apresentado por esses anuros. No laboratório os saltos foram mais longos, provavelmente por não existirem galhos ou folhas próximas onde o animal pudesse se refugiar. O desempenho no salto (distância máxima/CRC) foi maior no laboratório, onde as distâncias dos saltos foram maiores / Abstract: The present work had as objective to study the relation between jump performance, morphology and the habitat of Scinax hiemalis and S. similis (Amphibia. Anura) in Botucatu area. Tested examples were collected at Recanto Ecológico Sacae-Watanabe and Fazenda Experimental Lageado. The tests were performed in the laboratory and in the field, always after 6:00 pm. The animals had been tested in the Department of Zoology, in a rectangular track constructed on the basis of the works of Zug (1972 and 1978). The track is constituted of a surface of 1,0m of width by 2,75m of length, delimited for two walls of 1,0m of height, with the closed final extremity. The surface of the track was covered with paper of bundle for marking the distance of the jump of each individual. The results obtained show that there is no significant relevance between the hindlimb lenght and jump distance. There was also verified that there is no relation between the snout-vent length (SVL) and the jumped distance. There was difference in the presented behavior of the animals of both species. S. similis had demonstrated to be more active by jumping when it feels threatened, meanwhile S. hiemalis jumped when it was touched by the predator's tongue. In the field animals do not jump that much and their jumps are short, probably because the environment where they live (forest) and the cryptic colour pattern of these anura. In laboratory the jumps were longer, because there were no twigs or leaves nearby where the animal could find shelter. The jumping performance (maximum distance/ SVL) was bigger in the laboratory, where the jumped distances were bigger / Mestre
102

Estudo do desempenho no salto de duas espécies de Scinax de Botucatu (Amphibia, Anura, Hylidae)

Shimizu, Renata Duarte [UNESP] 01 April 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-01Bitstream added on 2014-06-13T18:59:57Z : No. of bitstreams: 1 shimizu_rd_me_botib.pdf: 312157 bytes, checksum: cf4b17bb7f3cebdbe8bdbd2ded38f81c (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O presente trabalho teve como objetivo estudar a relação entre o desempenho do salto, a morfologia e o habitat ocupado por Scinax hiemalis e S. similis (Amphibia. Anura) da região de Botucatu. Os exemplares testados foram coligidos no Recanto Ecológico Sacae-Watanabe e na Fazenda Experimental Lageado. Os testes foram realizados no laboratório e no campo, sempre após as 18:00h. Os exemplares foram testados na sala do Departamento de Zoologia, em uma pista retangular construída com base nos trabalhos de Zug (1972 e 1978). A pista é constituída de uma superfície de 1,0m de largura por 2,75m de comprimento, delimitada por duas paredes de 1,0m de altura, com a extremidade final fechada. O chão da pista foi coberto com papel de embrulho para marcação da distância do salto de cada indivíduo. Os resultados obtidos demonstraram que não há relação significativa entre as medidas dos membros posteriores e a distância do salto. Verificou-se também que não há relação entre o comprimento rostro-cloacal (CRC) e a distância do salto. Houve diferença no comportamento apresentado pelos animais das duas espécies, com S. similis demonstrando ser mais ativa e saltando quando se sentia ameaçada, enquanto S. hiemalis saltava quando tocada pela língua do predador. No campo os exemplares de S. hiemalis saltaram pouco e os saltos foram geralmente curtos, provavelmente devido ao ambiente que habitam (mata) e ao padrão de coloração críptica apresentado por esses anuros. No laboratório os saltos foram mais longos, provavelmente por não existirem galhos ou folhas próximas onde o animal pudesse se refugiar. O desempenho no salto (distância máxima/CRC) foi maior no laboratório, onde as distâncias dos saltos foram maiores / The present work had as objective to study the relation between jump performance, morphology and the habitat of Scinax hiemalis and S. similis (Amphibia. Anura) in Botucatu area. Tested examples were collected at Recanto Ecológico Sacae-Watanabe and Fazenda Experimental Lageado. The tests were performed in the laboratory and in the field, always after 6:00 pm. The animals had been tested in the Department of Zoology, in a rectangular track constructed on the basis of the works of Zug (1972 and 1978). The track is constituted of a surface of 1,0m of width by 2,75m of length, delimited for two walls of 1,0m of height, with the closed final extremity. The surface of the track was covered with paper of bundle for marking the distance of the jump of each individual. The results obtained show that there is no significant relevance between the hindlimb lenght and jump distance. There was also verified that there is no relation between the snout-vent length (SVL) and the jumped distance. There was difference in the presented behavior of the animals of both species. S. similis had demonstrated to be more active by jumping when it feels threatened, meanwhile S. hiemalis jumped when it was touched by the predator’s tongue. In the field animals do not jump that much and their jumps are short, probably because the environment where they live (forest) and the cryptic colour pattern of these anura. In laboratory the jumps were longer, because there were no twigs or leaves nearby where the animal could find shelter. The jumping performance (maximum distance/ SVL) was bigger in the laboratory, where the jumped distances were bigger
103

Hodnocení skokové schopnosti hříbat / The evaluation of foals jumping abilities.

MENŠÍKOVÁ, Kateřina January 2008 (has links)
The aim of this work was pass judgment the jumping abilities of foals measured at freestyle jumping during one's year. By the help of videorecording and subsequently computer analyses was assessed 427 jumps in free scope performed by 6 mares and 6 stallions in year-class 2002, 2003, 2004. Video records were made out by digital video kamera CANON type DM {--} XM 2 E. Processing of video records is done through the use of a programme for work with digital video records Pinnacle Studio 9. Movement mechanics analysis is practised in a programme Lucia 32 G Version 4.11. Following parameters were observed during a jump: jump bow characterized by 4 angles formed deciding physical parts, maximum flexion of the forelimbs {--} carpal joint and fore fetlock joint, rise of the forelimbs, flexion of the hindlimbs above a jump - knee-joint, hock joint, hind fetlock joint, location of the maximum carpal flexion. To objective assessment was made evaluation by statistical packet R version 2. 2.4.1 (2006) with usage procedures of Linear Models and there was verified demonstrativeness of differences among particular horses. It is evident from the findings, that jumping abilities of horses during the horse rearing are approximately same, but some of the qualities may change by training. . The objectively values found out during judging of a jump by way of video analysis make it possible to gain more accurate pieces of information about jump abilities of a horse and these pieces of information are usable in breeding of horses for a show-jumping.
104

Popis a porovnání svalového aparátu lopatkového pletence vybraných druhů žab / Description and comparison of pectoral girdle muscular system in selected frog species

KUTÍLKOVÁ, Pavla January 2009 (has links)
In my thesis I was concerned with pectoral girdle muscular system in selected frog species, especially with the muscles of ventral side, which probably play a crucial role in frog jumping abilities (mainly in landing phase). I find out a lot of differences between particular species and I mean that some of those differences are straightly connected with jumping movements.
105

Efficient Monte Carlo methods for pricing of electricity derivatives

Nobaza, Linda January 2012 (has links)
>Magister Scientiae - MSc / We discuss efficient Monte Carlo methods for pricing of electricity derivatives. Electricity derivatives are risk management tools used in deregulated electricity markets. In the past,research in electricity derivatives has been dedicated in the modelling of the behaviour of electricity spot prices. Some researchers have used the geometric Brownian motion and the Black Scholes formula to offer a closed-form solution. Electricity spot prices however have unique characteristics such as mean-reverting, non-storability and spikes that render the use of geometric Brownian motion inadequate. Geometric Brownian motion assumes that changes of the underlying asset are continuous and electricity spikes are far from being continuous. Recently there is a greater consensus on the use of Mean-Reverting Jump-Diffusion (MRJD) process to describe the evolution of electricity spot prices. In this thesis,we use Mean-Reverting Jump-Diffusion process to model the evolution of electricity spot prices. Since there is no closed-form technique to price these derivatives when the underlying electricity spot price is assumed to follow MRJD, we use Monte Carlo methods to value electricity forward contracts. We present variance reduction techniques that improve the accuracy of the Monte Carlo Method for pricing electricity derivatives.
106

Transform analysis of affine jump diffusion processes with applications to asset pricing

Bambe Moutsinga, Claude Rodrigue 11 June 2008 (has links)
This work presents a class of models in asset pricing, whose underlying has dynamics of Affine jump diffusion type. We first present L´evy processes with their properties. We then introduce Affine jump diffusion processes which are basically a particular class of L´evy processes. Our motivation for these is driven by the fact that many financial models are built on them. Affine jump diffusion processes present good analytical properties that allow one to get close form formulas for a wide range of option pricing. The approach we use here is based on the paper by Duffie D, Pan J, and Singleton K. An example will show how incorporating parameters such as the volatility of the underlying asset in the model, can influence the resulting price of the financial instrument under consideration. We will also show how this class of models incorporate well known models, specially those used to model interest rates dynamics, like for instance the Vasicek model. / Dissertation (MSc (Mathematics of Finance))--University of Pretoria, 2008. / Mathematics and Applied Mathematics / unrestricted
107

Relação entre parâmetros biomecânicos e a aceleração no basquetebol / Relationship between biomechanics parameters and acceleration tasks on basketball players

Rodrigo Maciel Andrade 17 December 2009 (has links)
O objetivo do estudo foi investigar o construto da tarefa de múltiplas acelerações a partir de parâmetros biomecânicos de saltos verticais. 19 jogadoras da seleção brasileira adulta de basquetebol feminino realizaram o teste de múltiplas acelerações (teste T), salto vertical com contramovimento (SV) e salto vertical com contramovimento precedido de corrida (SVcorrida). Os parâmetros biomecânicos do SV foram, tempo de fase concêntrica (Tcon), pico de força de propulsão (PFP), tempo decorrido entre início da fase concêntrica e o pico de força de propulsão (TPFP), taxa de desenvolvimento de força (TDF) e impulso (I); para SVcorrida, velocidade média de aproximação (Velmédia), tempo total do movimento (Ttotal), pico de força passiva (PFPa), tempo decorrido entre início da fase de apoio e pico de força passiva (TPFPa), pico de força de propulsão (PFP), tempo decorrido entre início da fase de apoio e pico de força de propulsão (TPFPp), Load Rate (LR) e taxa de desenvolvimento de força (TDF). Para análise dos dados, inicialmente, recorreu-se a análise de componentes principais, revelando que 61,3% da variância total do SV foi explicada pelo componente predominantemente temporal (Tcon, TPFP e PFP) e 20,7% pelo componente predominantemente cinético (I e TDF); para SVcorrida, 58,7% da variância total foi explicada pelo componente predominantemente temporal (Ttotal, TPFPa, TPFPp, LR e TDF), 15,4% pelo componente predominantemente cinético (PFPa e PFP) e 12,8% pelo componente velocidade (Velmédia). Adicionalmente, foram reveladas correlações significantes de 0,55 (Tcon), -0,54 (Velmédia) e -0,49 (PFP) com o teste T, evidenciando um construto determinado pela capacidade de se gerar elevada força na fase concêntrica, reduzir o tempo de fase concêntrica e se aproximar do ponto de mudança de direção com elevada velocidade. / The main aim of the study was to investigate the multiple-acceleration task construct from vertical jumps biomechanics parameters. Nineteen female basketball players from Brazilian national team performed the multiple-acceleration test (T test), countermovement jump (VJ) and countermovement jump preceded by run (VJr). The VJ biomechanics parameters observed were: concentric phase duration (CPD), propulsion peak force (PPF), time to reach propulsion peak force (TPPF), rate of force development (RFD) and impulse (I); for VJr the parameters were mean velocity (MV), movement total duration (MTD), passive peak force (PaPF), time to reach passive peak force (TPaPF), propulsion peak force (PPF), time to reach propulsion peak force (TPpPF), load rate (LR) and rate of force development (RFD). Data were first analyzed by principal component analysis. The results showed that 61.3% of VJ variance could be explained by time factor (CPD, TPPF and PPF), and 20.7% by kinetic factor (I and RFD). To VJr, 58.7% of total variance could be explained by time factor (MTD, TPaPF, TPpPF, LR, RFD) and 15.4% by kinetic factor (PPF and PaPF) and 12.8% by velocity factor (MV). Furthermore, significant correlations were found between T test with CPD, MV and PPF (0.55, -0.54 and -0.49, respectively), revealing a T test construct related to the ability of generating high level of force in concentric phase, diminishing time of concentric phase, and to reach the change direction point with greatest possible speed.
108

Comparison of Static and Countermovement Jump Variables in Relation to Estimated Training Load and Subjective Measures of Fatigue

Sams, Matthew L 01 August 2014 (has links)
The purpose of this study was to compare changes in static and countermovement jump variables across a competitive season of collegiate soccer to estimated training load and subjective measures of fatigue. Monitoring data from 21 male collegiate soccer players were retrospectively examined. Nine vertical jump sessions occurred across the season in addition to daily training load assessment and daily mood-state assessment. Group average changes from the first testing session were calculated and compared to the group average training load for the 7 days preceding each vertical jump testing session for static and countermovement jump height and allometrically scaled peak power. Statistical analysis demonstrated strong relationships between changes in vertical jump height for both conditions, allometrically scaled peak power for static jumps, and estimated training load. The results indicate changes in static jump height and allometrically scaled peak power may be more useful athlete fatigue monitoring tools than countermovement jump variables.
109

Sambandsstudie mellan vertikalhopp, marklyft och BMI hos en grupp friska fysioterapeutstudenter / Correlation study between vertical jump, deadlift and BMI in a population with healthy physiotherapy students

Ark, Simon, Olausson, Filip January 2020 (has links)
Marklyft är en övning som effektivt tränar bland annat höftextensorer, som är en av de viktigaste muskelgrupperna för att utföra ett vertikalhopp. Trots detta har inga studier gjorts på korrelationen mellan marklyft och vertikalhopp, däremot finns flertalet studier gjorda på korrelation mellan knäböj och vertikalhopp. Syftet med denna studie var att undersöka eventuella samband mellan marklyft - vertikalhopp, vertikalhopp - BMI (Body Mass Index) och marklyft - BMI hos friska fysioterapeutstudenter (n = 15) på Uppsala Universitet. Detta för att undersöka om marklyft skulle kunna användas som alternativ träning för att förbättra personers vertikalhopp. Vertikalhopp mättes med elektronisk hoppmatta och marklyft med 1RM-test. BMI räknas ut med deltagarnas längd och vikt. Variablerna sammanställdes och sambandet räknades ut via Pearsons korrelationskoefficient. Resultaten visade ingen korrelation mellan vertikalhopp och marklyft (p = 0,773, r = 0,083) och en svag negativ korrelation för BMI och vertikalhopp (p = 0,514, r = -0,188). En mycket stark positiv korrelation mellan BMI och marklyft (p = 0,013, r = 0,721) påträffades, där de med högre BMI lyfte mer i marklyft. Slutsatsen av studien resulterar i att marklyft inte borde rekommenderas som en alternativ övning för att förbättra vertikalhoppsförmågan. Dock behövs fler studier med bland annat fler deltagare för att vidare undersöka eventuella kliniska tillämpningar. / Deadlift is an exercise that proves to effectively train the hip extensors amongst other muscle groups, which is one of the most important muscle groups for performing a vertical jump. Despite this connection, no studies have been made on the correlation between deadlifts and vertical jumps, contrary to the numerous studies made regarding the correlation between squat and vertical jump. The purpose of this study was to examine the possible correlation between deadlifts, vertical jumps as well as BMI (Body Mass Index) amongst healthy physiotherapy students (n=15) at Uppsala University. This to assess the use of deadlift as an alternative training method to improve a person’s vertical jump ability. Vertical jumps were measured with an electronic jump mat and deadlifts were measured with 1RM-test. BMI was calculated using the person’s height and weight. The variables were then compiled and calculated using Pearson's correlation coefficient. The results presented no correlation between vertical jumps and deadlifts (p = 0,773, r = 0,083), and a weak negative correlation between BMI and vertical jumps (p = 0,514, r = -0,188). A very strong positive correlation between BMI and deadlifts (p = 0,013, r = 0,721) was detected, whereas participants with higher BMI lifted more in deadlift. The conclusion of this study dictates that deadlift should not be recommended as an alternative exercise to improve vertical jump ability. However, more studies with larger populations are needed to scrutinize clinical applications.
110

Performance Comparisons of Youth Weightlifters as a Function of Age Group and Sex

Mizuguchi, Satoshi, Cunanan, Aaron J., Suarez, Dylan G., Cedar, William E., South, Mark A., Gahreman, Daniel, Hornsby, William G., Stone, Michael H. 01 September 2021 (has links)
This study was designed to provide an overview of weightlifting performance as a function of age group and sex and evaluate the potential of countermovement jump height (CMJH) as a tool to gauge performance potential. Data from 130 youth athletes (female, n = 65 & male, n = 65) were used to examine progression of performance (Total and Sinclair total) and the relationship between CMJH and Sinclair total while considering interactions between CMJH and age and/or sex. ANOVAs with post hoc analyses revealed that both totals had a statistical first-order polynomial interaction effect between age group and sex and the difference between age groups of 12–13 and 14–15 years old was statistically greater for male than female. A linear model, developed to examine the relationship, revealed that CMJH and CMJH x sex x age rejected the null hypothesis. Our primary findings are that male youth weightlifters have a higher rate of performance progression, possibly owing to puberty, and CMJH may be a better gauging tool for older male youth weightlifters.

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