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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

Vliv palce nohy na stabilitu stoje a chůze / The influence of hallux on stand and gait stability

Hlinková, Zuzana January 2008 (has links)
The diploma thesis "Vliv palce nohy na stabilitu stoje a chůze" is focused on the function of hallux at stance and through the gait cycle and particularly to halluxes influence on stability of the stated motor stereotypes. The theoretical part summarizes the knowledge gained through literature research on anatomy and kinesiology of hallux. It also contains analysis of gait cycle and muscle coordination through it with emphasis upon activity of foot and function of hallux muscles. The practical part attempts to objectivize changes in stability and changes of loading of foot with instrumental examination. Force plate Balance Master® and GaitPlatform FDM were used for the measurements. On the force plate the parametres of movement of the centre of mass (COM, COG) and maintenance of stability while standing were compared. GaitPlatform® was used for measurement of ground reaction forces while standing and walking. Powered by TCPDF (www.tcpdf.org)
102

Influência da neuropatia diabética no comportamento de respostas biomecânicas e sensoriais no andar em esteira rolante / Influence of the diabetic neuropathy on the behavior of biomechanical and sensorial responses in treadmill gait

Isabel de Camargo Neves Sacco 28 August 2001 (has links)
A investigação de parâmetros biomecânicos no movimento humano tem trazido importantes discussões sobre a função do sistema músculo-esquelético e o controle deste movimento. O andar humano é um dos comportamentos motores mais investigados pela biomecânica e seus aspectos mecânicos contribuem de forma a caracterizar, identificar e intervir em situações patológicas. A investigação de parâmetros dinâmicos, cinemáticos e eletromiográficos na marcha patológica pode beneficiar de forma significativa a compreensão dos mecanismos de controle do andar e as alterações compensatórias geradas, assim como contribuir nas intervenções terapêuticas e preventivas em sujeitos portadores de alguma doença que acometa o sistema músculo-esquelético. No presente estudo, buscou-se descrever e interpretar, sob a perspectiva da biomecânica, o andar em cadência auto-selecionada de sujeitos diabéticos neuropatas em esteira rolante, considerando os parâmetros dinâmicos, temporais, espaciais e eletromiográficos durante a fase de apoio. Investigou-se também aspectos sensoriais plantares e motores a fim de caracterizar os sujeitos neuropatas e controles estudados. Valores da sensibilidade somatossensorial e limiares de tolerância à dor nos sujeitos diabéticos neuropatas apresentaram significativamente maiores em relação ao grupo de sujeitos controle estudado, valores considerados fora do padrão de normalidade esperado. A cadência autoselecionada e a velocidade obtida na esteira rolante foram significativamente menores durante o andar dos neuropatas em relação aos sujeitos controle. Os tempos de apoio simples, duplo, comprimento da passada e do passo durante a marcha nos sujeitos diabéticos neuropatas apresentaram-se significativamente maiores em relação ao grupo controle. Foram observados menores picos de força vertical nos sujeitos neuropatas e menores deflexões da força vertical, conseqüências secundárias da estratégia de redução da velocidade do andar em neuropatas que buscam um padrão mais conservativo e estável do seu andar. As respostas eletromiográficas dos músculos da perna e coxa apresentaram-se com menores magnitudes e com picos de ativação atrasados em relação ao padrão normal de recrutamento, especialmente o m. tibial anterior bilateralmente nos neuropatas. Interpreta-se tal fato como uma provável alteração no mecanismo de controle central e/ou periférico da marcha em sujeitos diabéticos neuropatas decorrente dos déficits sensoriais periféricos e motores conseqüentes da doença investigada. O mecanismo de redução de choques na marcha apresentou-se de forma ineficiente em função das respostas atrasadas eletromiográficas tanto de m. vasto lateral, quanto de m. tibial anterior. Conclui-se que a neuropatia diabética periférica acomete não só respostas somatossensoriais e motoras periféricas mas também mecanismos intrínsecos de controle modificando a eficiência do tornozelo em seu papel na marcha, comprometendo desta forma alguns dos principais requisitos para o andar que são a progressão e o equilíbrio / Biomechanical investigation of the human movement has been bringing important discussions about the musculoskeletal system functions and the control of movement. The human walking is one of the most studied motor behaviors and its mechanical aspects contribute to characterize, identify, and intervene in pathological conditions. Dynamic, kinematic, and electromyographic analyses of pathological gait can significantly help the comprehension of the control mechanism of gait and its compensatory alterations. These analyses can also contribute to therapeutic and preventive interventions in patients whose walking behavior is altered due to some disease that accomplish the neuromotor system. In the present study, we described and interpreted self-cadence walking in a treadmill of neuropathic diabetic subjects under biomechanical considerations, such as dynamic, temporal, spatial, and electromyographic analysis during stance phase. We also studied sensorial and motor aspects in order to characterize the neuropathic and control subjects. The somatossensorial responses and pain tolerance threshold in the neuropathic subjects were significantly higher and considered away from the normal patterns. The self-cadence and the treadmill velocity were significantly lower in neuropathic gait. Single and double stance time, stride and step length were significantly higher during neuropathic gait. The neuropathic subjects showed lower vertical force peaks and lower deflections of vertical force and those findings were secondary consequences of the conservative strategy of lowering the gait velocity adopted by the neuropathic in order to reach a more stable locomotor pattern. The electromyographic responses of the thigh and leg muscles in neuropathic subjects showed lower magnitudes and were delayed comparing to the normal recruitment pattern, specially the anterior tibialis muscle right and left. These findings lead us to conclude that probably central and/or peripheral control mechanisms of the gait of neuropathic diabetic patients are altered due to somatossensorial and motor deficits. The mechanism of load reduction during walking was considered inefficient because of the activation delay of the lateral vastus and anterior tibialis muscles. We conclude that the peripheral diabetic neuropathy damages not only somatossensorial and motor sources but also intrinsic mechanisms of motor control leading to alterations in the ankle efficiency in gait. This resulting distal inefficiency compromises some of the principal requirements to gait, which are progression and balance
103

Optimization of a cutter wheel bearing / Optimering av lagring till cutterhjul

Fagrell, William January 2020 (has links)
This Master's thesis project was provided by Epiroc Rock Drills AB and conducted at Camatec Industriteknik AB in Karlstad, Sweden. The project is centered around the cutter wheel in the mechanical rock excavator Mobile Miner 40V.  This cutter wheel is equipped with cutter discs that grind rock into debris as the wheel rotates and thrusts forward. The internal system consisting of a bearing constellation and the components in its vicinity has experienced a certain degree of wear in the form of scuffing and this was detected on the surfaces of some of the components in the system. The reasons for this occurrence are unknown and per the request of the thesis provider, this was to be determined. The thesis provider also requested a new Finite Element Analysis (FEA) model of the system along with feasible load cases that can be applied to said model. The project was deemed extensive and was therefore decided to be conducted by two students. This thesis covers the determination of the load cases as well as the optimization of the current design of the system inside the cutter wheel. During the pre-study, relevant background data was obtained for the cutter wheel and the internal system. Methods and models considered to potentially be useful were also gathered. The system in question was divided into two separate models; one consisted of a tribo-system with two components in sliding contact and the other consisted of the bearing constellation along with the outer-most section of the cutter wheel. The purpose of the first model was to use it to determine the contact pressure between the tribo-surfaces and by doing so, be able to determine the expected lubrication regime for the oil in the tribo-system. A material selection process was also conducted on the tribo-surface that had experienced the most severe surface damage. Additionally, minor reconstructions were made with the purpose of optimizing the system. The purpose of the second model was to apply the calculated load cases to the cutter disc attachments located on the outer-most section of the cutter wheel and then determine the contact pressures that develop on the bearing roller elements. The results of the thesis work consist of five potential material options, two reconstructions and 60 different load cases for the FEA model. With the load cases, the largest contact pressures on the bearing roller elements was determined. In addition, the cause of the severe surface damage that had occurred in the system is believed to have been identified. Further work on the project work is believed to be required. Future work of interest are determining load cases that incorporate multiple cutter discs simultaneously in contact with the rock, reconstruction solutions for the oil inlet and outlet pipes, a more thorough materials selection process and a criterion for the expected lubrication regime in the tribo-system based on tests performed with materials that are more identical to the ones in this project. / Detta examensarbete tillhandahölls av Epiroc Rock Drills AB och genomfördes hos Camatec Industriteknik i Karlstad, Sverige. Projektet är centrerat kring cutterhjulet i maskinen Mobile Miner 40V som är avsedd för mekanisk bergavverkning. Cutterhjulet är utrustat med cutter discar som maler berget till mindre flisor genom att hjulet roterar och trycks framåt. Det inre systemet bestående av en lagring med närliggande komponenter har utsatts för en viss grad av nötning i form av scuffing och detta upptäcktes på ytorna hos vissa av komponenterna i systemet. De bakomliggande anledningarna för denna förekomst är okända och utifrån begäran från projektgivaren skulle dessa anledningar fastställas. Projektgivaren eftersökte även en ny FEM-modell av systemet tillsammans med rimliga lastfall som ska kunna appliceras på modellen i fråga. Projektet ansågs tämligen omfattande och det bedömdes därför att två studenter krävdes för att genomföra arbetet. Denna uppsats behandlar framtagningen av lastfallen såväl som optimeringen av den nuvarande designen av systemet inuti cutterhjulet. Under förstudien hämtades relevant bakgrundsdata för cutterhjulet och det interna systemet. Metoder och teorier som ansågs vara potentiellt användbara samlades även in. Systemet i fråga delades in i två separata modeller; en bestod av ett tribo-system bestående av två tribo-ytor i glidande kontakt och den andra bestod av lagringen tillsammans med den yttersta sektionen hos cutterhjulet. Syftet med den förstnämnda modellen var att använda den för att bestämma kontakttrycket mellan tribo-ytorna, och genom detta kunna fastställa den förväntade smörjningsregimen hos oljan i tribo-systemet. En materialvalsprocess utfördes även för tribo-ytan som hade utsatts för den mest allvarliga skadan. Även smärre omkonstruktioner utfördes med syftet att optimera systemet. Syftet hos den andra modellen var att kunna applicera de beräknade lastfallen på cutter discarnas infästningar som återfinns i den yttersta sektionen hos cutterhjulet och sedan bestämma kontakttrycken som uppstår på rullarna i lagren. Resultaten från arbetet består av fem potentiella materialval, två konstruktionsändringar och 60 olika lastfall för FEM-modellen. Genom att applicera lastfallen bestämdes de största kontakttrycken på lagrens rullar. Utöver detta anses det att anledningen för den allvarliga ytskadan som hade skett i systemet har identifierats. Det anses att fortsatt arbete krävs för projektet. Kompletterande arbete som anses vara av intresse är lastfall som inkluderar flera cutter discar i ingrepp samtidigt med berget, konstruktionslösningar för tillförsel och bortförsel av oljan, en mer djupgående materialvalsprocess och ett kriterium för förväntad smörjningsregim hos tribo-systemet baserat på tester utförda med material som är mer identiska med dem som förekommer i projektet.
104

Ground Reaction Force Prediction during Weighted Leg Press and Weighted Squat in a Flywheel Exercise Device / Estimering av markreaktionskraften vid viktad benpress och viktad knäböj i ett svänghjulsbaserat träningsredskap

Munkhammar, Tobias January 2017 (has links)
When performing a biomechanical analysis of human movement, knowledge about the ground reaction force (GRF) is necessary to compute forces and moments within joints. This is important when analysing a movement and its effect on the human body. To obtain knowledge about the GRF, the gold standard is to use force plates which directly measure all three components of the GRF (mediolateral, anteroposterior and normal). However, force plates are heavy, clunky and expensive, setting constraints on possible experimental setups, which make it desirable to exclude them and instead use a predictive method to obtain the full GRF. Several predictive methods exist. The node model is a GRF predictive method included in a musculoskeletal modeling software. The tool use motion capture and virtual actuators to predict all three GRF components. However, this model has not yet been validated during weighted leg press and weighted squat. Furthermore, the normal component of the GRF can be measured continuously during the activity with pressure sensitive insoles (PSIs), which might provide better accuracy of the GRF prediction. The objectives of this thesis were to investigate whether force plates can be exluded during weighted leg press and weighted squat and to investigate whether PSIs can improve the GRF prediction. To investigate this, the node model and a developed shear model was validated. The shear model computes the two shear GRF components based on data from PSIs, an external load acting upon the body and data from a motion capture system. Both the node model and the shear model were analysed with two test subjects performing two successive repetitions of both weighted squat and weighted leg press in a flywheel exercise device. During the leg press exercise, the node model had a mean coeffcient of correlation (Pearson's) ranging from 0.70 to 0.98 for all three directions with a mean root mean square error ranging between 8 % to 20 % of the test person's body weight. The developed shear model had a coeffcient of correlation (Pearson's) between 0.64 to 0.99 and a mean root mean square error between 3 % and 21 % of the test person's body weight. This indicates that it is possible to exclude force plates and instead predict the GRF during weighted leg press. During squat, neither the node model nor the shear model provided accurate results regarding the mediolateral and anteroposterior components of the GRF, suggesting that force plates can not yet be excluded to obtain the full GRF during weighted squat. The results of the normal component during leg press was somewhat improved with the shear model compared to the node model, indicating that using PSIs can improve the results to some extent.
105

Efficacy of a 6-week Neuromuscular Training Program for Improving Postural Control in Figure Skaters

Saunders, Nathan William 20 July 2011 (has links)
No description available.
106

Les défis de la politique européenne de défense

Ribet, Roseline 06 1900 (has links)
"Thèse présentée à la Faculté des études supérieures en vue de l'obtention du grade de Docteur en droit (LL.D) et à l'Université Jean Moulin en vue de l'obtention du grade de Docteur en droit" / Les États européens n'ont, jusque dans les années 90, envisagé leur défense que dans le cadre d'alliances militaires et restaient maîtres de leur défense nationale. La mise en place d'une politique européenne de défense a toujours connu des obstacles, reflets des problèmes de souveraineté. Dans l'Union européenne, l'intégration politique, et en particulier celle de la défense, reste le domaine le plus incertain. Cette thèse de nature essentiellement empirico-descriptive aborde le thème de la défense européenne sous une approche réaliste, en plaçant les États au centre de la construction européenne et en en faisant les acteurs principaux. Depuis 1992, les États tentent de définir une politique européenne de défense mais rencontrent différentes difficultés. En effet, la politique européenne de défense souffre d'un double déficit. Le premier est un déficit institutionnel puisque la P.E.D. est loin d'être une politique commune et se limite à un mécanisme de coopération. Le second est un déficit matériel puisque l'Union européenne n'a pas la puissance militaire pour mettre en oeuvre une éventuelle décision commune. Afin d'évaluer les perspectives d'évolution d'une politique européenne de défense, nous devons étudier les différents défis que les États et les institutions communautaires doivent relever pour combler ces deux déficits. Les défis d'ordre institutionnel concernent les multiples acteurs, États et institutions, qui interviennent dans la définition de la P.E.S.D. Il s'agit de déterminer quelle instance est la mieux à même d'assurer la représentation internationale de l'Union européenne afin de donner l'impulsion politique nécessaire de la P.E.S.D. Les défis d'ordre militaire concernent les moyens que les différents acteurs souhaitent engager afin de concrétiser la politique définie. Toutes ces discussions montrent la justification d'un système européen de défense mais la question est de savoir si les États, acteurs centraux de la construction européenne, sont prêts à relever ces défis. / Up until the 1990's, the European States have solely thought of their security forces inside military alliances as they kept control of their national defense. The putting in place of a European defense policy has always met obstacles, which reflect the problems linked to the preservation of sovereignty. The political integration in Europe remains uncertain, mostly when it comes to common defense. With an empirical and descriptive manner, this thesis depicts the European defense theme in a realistic approach, by placing the States in the middle of the European construction and by giving them the main role. Since 1992, the States tried to lay down a European policy of defense, but they encountered various difficulties. Indeed, the European policy of defense suffers from a double deficit. The first is institutional since the European Defense Policy is far from being part of a common policy and is strictly a cooperation mechanism. The second is a material deficit since the European Union doesn't have a military force to implement a common decision. In order to evaluate the possible evolution of a European defense policy, we had to study the various challenges that the States and institutions must face in order to address those two deficits. The institutional challenge concerns the multiple actors, States and institutions, which intervene in the definition of E.P.S.D. This part will try to identify which institution would be best capable of ensuring the international representation of the European Union and to give the political impetus necessary to the putting into place of the E.P.S.D. The military challenge concern the means that the different actors would engage in order to concretize the policy. Ali these discussions show the justification of a European system of defense, but the question remains as to whether the States, central figures of the European construction, are ready to take up these challenges.
107

Modelagem numérica dos fenômenos que ocorrem durante a penetração do amostrador SPT no solo / Numerical modelling of the penetration of a SPT sampler into the soil

Quintero Baños, Julieth Paola 16 June 2016 (has links)
O ensaio SPT (Standard Penetration Test), é o ensaio de campo geotécnico mais usado no Brasil e grande parte do mundo. A ampla utilização deste ensaio no âmbito da engenharia geotécnica deve-se à sua simplicidade, baixo custo, grande experiência prática e facilidade de aplicação dos seus resultados. Os principais objetivos do ensaio são a determinação do índice de resistência do solo (NSPT) e amostragem. Apesar de ser muito utilizado na estimativa da capacidade de carga de fundações, o ensaio SPT tem sido questionado pelo fato de que o índice NSPT é utilizado em correlações empíricas baseadas em observações práticas, sem nenhum fundamento científico. Além do mais, seus resultados apresentam significativas dispersões. Para analisar racionalmente os resultados do ensaio e de possibilitar a comparação dos diferentes resultados de distintas equipes, é necessário conhecer as quantidades de energia envolvidas na penetração do amostrador no solo. Tais análises requerem o conhecimento da eficiência do equipamento (η) e a força de reação dinâmica do solo à cravação do amostrador (RD). Neste cenário, o presente trabalho aborda a interpretação racional dos resultados de ensaios SPT a partir de simulações numéricas realizadas com o software Abaqus/Explicit®. Esse programa fornece os deslocamentos do amostrador (Δρ), força de reação dinâmica do solo (RD), e as forças de reação nas paredes laterais externa e interna do amostrador (R1 e R2). Baseando-se nos resultados dos modelos numéricos, foi possível calcular a eficiência do equipamento, a partir da força de reação dinâmica do solo, as resistências unitárias de atrito atuantes nas paredes e a resistência unitária na ponta do amostrador. Também foi possível determinar a relação entre as resistências unitárias de atrito desenvolvidas no interior e exterior do amostrador (fator de atrito a). Os resultados obtidos foram comparados com resultados de trabalhos experimentais e valores teóricos determinados com base no Princípio de Hamilton da conservação da energia. Também foi possível simular uma prova de carga dinâmica com energia crescente no amostrador, variando a altura de queda do martelo. Isso confirmou que a resistência mobilizada do solo para certa energia aplicada pode estar bem abaixo da ruptura e apenas representar um ponto na curva de resistência mobilizada versus deslocamento. / The Standard Penetration Test (SPT) is one of the most used geotechnical tests in the world. The wide use of this test in the context of geotechnical engineering is due to its simplicity, low cost, large practical experience and its ease of application of results. The main objectives of the test are the determination of soil resistance index (NSPT) and sampling. Despite being widely used in estimating the bearing capacity of foundations, the SPT test has been questioned by the fact that the NSPT index is used in empirical correlations based on practical observations, with no scientific basis. Furthermore, its results show significant dispersions. To analyze rationally the test results and to make possible to compare different results obtained from different equipment, it is necessary to know the amounts of energy existing during the penetration of the sampler into soil. Such analyses require information about the equipment efficiency (η) and the dynamic soil reaction force during the sampler penetration (RD). In this scenario, this work addresses the rational interpretation of SPT test results from numerical simulations performed with the Abaqus/Explicit software. This program provides the sampler displacements (Δρ), the dynamic soil reaction force (RD) and the external and internal reaction forces acting on the sampler walls (R1 e R2). Based on the results of the numerical models, it was possible to calculate the efficiency of the equipment, from the dynamic soil reaction force, the unit friction resistance acting on the sampler walls and the unit resistance at the sampler tip. In addition, it was possible to estimate the relationship between the unit friction resistance acting on the internal and external walls of the sampler (friction factor a). The numerical results were compared with experimental results and theoretical values, obtained using the Hamilton\'s principle of conservation of energy. Furthermore, it was possible to simulate a dynamic load test with increasing energy applied to the sampler, by varying the height of fall of the hammer. It was obtained the confirmation that resistance mobilized for a certain level of energy applied to the sampler may be below the failure load and represent only a point on the graph curve mobilized resistance versus displacement.
108

Interpretação de resultados do ensaio SPT com base em instrumentação dinâmica / Interpretation of SPT test results based on dynamic instrumentation

Lukiantchuki, Juliana Azoia 27 July 2012 (has links)
O ensaio de simples reconhecimento do solo (SPT) e usualmente utilizado para estimar a resistência do solo, atraves do índice NSPT, que representa a resistencia a penetração dinâmica do amostrador no solo. Esse índice é usado diretamente em correlações empíricas ou semi-empíricas na determinação da capacidade de suporte e recalque das fundações. Entretanto, esse ensaio tem sido alvo de críticas devido a utilização dessas correlações empíricas, geralmente baseadas em observações práticas e sem nenhum fundamento científico. Críticas também estão relacionadas com a dispersão dos resultados, devido a utilização de diferentes tipos de equipamentos e procedimentos executivos. O índice NSPT depende da parcela de energia que e efetivamente transmitida ao amostrador durante a queda do martelo. Assim, análises racionais dos resultados de ensaios SPT dependem essencialmente da estimativa da quantidade dessa energia. Por esse motivo, tem sido desenvolvidas diversas pesquisas relacionados com a energia envolvida no ensaio SPT. Este trabalho apresenta interpretações dos resultados do ensaio SPT a partir das quantidades de energia envolvidas durante a queda do martelo. Essas quantidades de energia são determinadas indiretamente, através dos sinais de força normal e aceleração durante a propagação da onda de tensão ao longo da composição de hastes. Para isso, foi desenvolvido um equipamento que inclui uma instrumentação capaz de registrar esses sinais de força normal e aceleração. Uma série de ensaios SPT foi realizada com instrumentação instalada tanto no topo como na base da composição de hastes. Esse arranjo permitiu estimar as quantidades de energia disponíveis no topo e na base da composição de hastes. Assim, foi possível determinar a eficiência dos equipamentos SPT com base na quantidade de energia que efetivamente atinge o amostrador. A partir dos sinais registrados, também foi possível determinar a resistência dinâmica mobilizada no sistema solo-amostrador. Os resultados experimentais foram comparados com resultados obtidos através de métodos teóricos, baseados no Princípio de Hamilton, para a determinação da resistência estática e dinâmica do solo. Essas análises mostraram que equações teóricas podem ser adequadas para a determinação da resistência do solo, desde que seja considerada a quantidade de energia que efetivamente atinge o amostrador. Desta forma, essas equações teóricas podem ser facilmente incorporadas na prática de projeto de fundações, contribuindo para o desenvolvimento de métodos baseados na quantidade de energia necessária para a penetração do amostrador no solo. / The standard penetration test (SPT) is usually used to estimate the soil strength through the NSPT index which represents the dynamic reaction force of the sampler penetration into the soil. This index is directly used in empirical or semi-empirical correlations for the determination of the bearing capacity and foundation settlements. However, this test has been criticized due to the use of these empirical correlations, often based on practical observation without any scientific basis. Criticism is also related to result dispersion due to the use of different types of equipment and execution procedures. The NSPT index depends on the amount of energy that is effectively transmitted to the sampler during the hammer fall. Thus, rational analyses of the SPT test results essentially depend on the estimation of this amount of energy. For this reason, several studies related to the energy involved in SPT test have been developed. This research presents interpretations of the SPT test results from the amounts of energy involved during the hammer fall. These amounts of energy are indirectly assessed by means of normal force and acceleration signals during the stress wave propagation along the string of rods. For this reason, a device that includes instrumentation capable of registering these signals of normal force and acceleration was developed. A series of tests was performed with the instrumentation installed at the top and the bottom of the string of rods. This arrangement allowed estimating the amount of energy available at the top and bottom of the string of rods. Thus, it was possible to estimate the efficiency of the SPT equipment basing on the amount of energy that actually reaches the sampler. From the recorded signals, it was also possible to assess the dynamic reaction force mobilized in the soil-sample system. The results were compared with other results obtained by theoretical methods, based on the Hamilton´s Principle, for evaluating the static and dynamic reaction force of the soil. These analyzes have shown that theoretical equations may be suitable for the determination of the soil strength, provided that the amount of energy that actually reaches the sampler be considered. Thus, these theoretical equations can be easily incorporated into the practice of foundation designs contributing to the development of methods based on the amount of energy required for the penetration of the sampler into the soil.
109

Les défis de la politique européenne de défense

Ribet, Roseline 06 1900 (has links)
Les États européens n'ont, jusque dans les années 90, envisagé leur défense que dans le cadre d'alliances militaires et restaient maîtres de leur défense nationale. La mise en place d'une politique européenne de défense a toujours connu des obstacles, reflets des problèmes de souveraineté. Dans l'Union européenne, l'intégration politique, et en particulier celle de la défense, reste le domaine le plus incertain. Cette thèse de nature essentiellement empirico-descriptive aborde le thème de la défense européenne sous une approche réaliste, en plaçant les États au centre de la construction européenne et en en faisant les acteurs principaux. Depuis 1992, les États tentent de définir une politique européenne de défense mais rencontrent différentes difficultés. En effet, la politique européenne de défense souffre d'un double déficit. Le premier est un déficit institutionnel puisque la P.E.D. est loin d'être une politique commune et se limite à un mécanisme de coopération. Le second est un déficit matériel puisque l'Union européenne n'a pas la puissance militaire pour mettre en oeuvre une éventuelle décision commune. Afin d'évaluer les perspectives d'évolution d'une politique européenne de défense, nous devons étudier les différents défis que les États et les institutions communautaires doivent relever pour combler ces deux déficits. Les défis d'ordre institutionnel concernent les multiples acteurs, États et institutions, qui interviennent dans la définition de la P.E.S.D. Il s'agit de déterminer quelle instance est la mieux à même d'assurer la représentation internationale de l'Union européenne afin de donner l'impulsion politique nécessaire de la P.E.S.D. Les défis d'ordre militaire concernent les moyens que les différents acteurs souhaitent engager afin de concrétiser la politique définie. Toutes ces discussions montrent la justification d'un système européen de défense mais la question est de savoir si les États, acteurs centraux de la construction européenne, sont prêts à relever ces défis. / Up until the 1990's, the European States have solely thought of their security forces inside military alliances as they kept control of their national defense. The putting in place of a European defense policy has always met obstacles, which reflect the problems linked to the preservation of sovereignty. The political integration in Europe remains uncertain, mostly when it comes to common defense. With an empirical and descriptive manner, this thesis depicts the European defense theme in a realistic approach, by placing the States in the middle of the European construction and by giving them the main role. Since 1992, the States tried to lay down a European policy of defense, but they encountered various difficulties. Indeed, the European policy of defense suffers from a double deficit. The first is institutional since the European Defense Policy is far from being part of a common policy and is strictly a cooperation mechanism. The second is a material deficit since the European Union doesn't have a military force to implement a common decision. In order to evaluate the possible evolution of a European defense policy, we had to study the various challenges that the States and institutions must face in order to address those two deficits. The institutional challenge concerns the multiple actors, States and institutions, which intervene in the definition of E.P.S.D. This part will try to identify which institution would be best capable of ensuring the international representation of the European Union and to give the political impetus necessary to the putting into place of the E.P.S.D. The military challenge concern the means that the different actors would engage in order to concretize the policy. Ali these discussions show the justification of a European system of defense, but the question remains as to whether the States, central figures of the European construction, are ready to take up these challenges. / "Thèse présentée à la Faculté des études supérieures en vue de l'obtention du grade de Docteur en droit (LL.D) et à l'Université Jean Moulin en vue de l'obtention du grade de Docteur en droit"
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Effects of Jump Training on Bone Mineral Density in Young Adult Females

Zagdsuren, Battogtokh 01 May 2014 (has links)
Physical activity is critical to bone health. However, not all physical activity has optimum effect on bone health and metabolism. The purpose of this study was to determine the effects of a short term progressive jumping protocol on bone mineral density in college age Asian females. Sixteen participants aged18-28 years enrolled in the study. Participants were assigned to exercise (n=9) and control (n=8) groups. The exercise group completed a two-legged depth jump from an approximate 20cm stepbench followed immediately by a maximum vertical jump using arm swings for five days per week for two weeks. Each depth jump and vertical jump was performed ten times during each session. The exercise intervention progressed from one session per day to three sessions per day in ten days. The bone mineral density (BMD) by dualenergy x-ray absorptiometry (DXA), ground reaction force (GRF), bone specific physical activity questionnaire (BPAQ), and dietary log were administered to the participants pre- and post-intervention. The data were analysed using a dependent t-test and one-way repeated measures. There were no significant changes noted in BMD value in the study. The past BPAQ showed significant correlation to BMD change of left hip (p<0.01) in exercise group. The vertical GRF showed significant increase (p<0.05) in exercise group. It can be concluded from the study that intensity of the progressive jumping was intense enough to stimulate some changes in the bone metabolism.

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