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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.
41

The Effect of Squat Load and Depth on Patellofemoral Joint Kinetics

Cotter, Joshua Allan 03 September 2009 (has links)
No description available.
42

Muskulär profilering av underkroppen hos manliga amatörklättrare. : En undersökning av styrka och power i nedre extremiteter hos klättrare på avancerad och moderat nivå / Muscular profiling of the lower body of male amateur climbers. : A study of strength and power in the lower extremities on climbers at advanced and moderate level

Hägglund, Eva, Nyman, Filip January 2018 (has links)
Klättring som utförs på överhängande ytor blir allt vanligare och kräver mer avancerad användning av underkroppen. Då tidigare forskning i synnerhet undersökt överkroppsstyrka saknas en muskulär profilering av underkroppen hos klättrare vilket således var syftet med denna studie. Frågeställningarna eftersträvade att undersöka om skillnader i styrka och power i nedre extremiteter kan relateras till prestation hos manliga klättrare. Deltagarna var 10 manliga amatörklättrare som delades in i 2 grupper baserat på idrottsspecifik prestationsnivå. Grupp 1 (n=6) kategoriserades som avancerade klättrare och grupp 2 (n=4) som moderata. Ett isokinetiskt styrketest och två olika hopptester genomfördes av samtliga studiedeltagare. Efter statistisk analys framgick det att det inte fanns några signifikanta skillnader (p= 0,05) mellan grupperna gällande relativ styrka i quadriceps, relativ styrka i hamstrings, H/Q-kvot, hopphöjd vid SJ eller hopphöjd vid CMJ. Gruppen med mer avancerade klättrare presterade signifikant högre vid CMJ kontra SJ (p=0,013). Slutsatserna av denna studie är att klättrare har förhållandevis låga resultat både vid mätning av H/Q-kvot vid 90°/s (grupp 1: 51% vs. grupp 2: 53,9%), 210°/s (59,4% vs. 57,9%) och vid vertikala hopptester (SJ: 32,1cm vs. 31,7cm; CMJ: 35,8 cm vs. 33,9 cm) samt att hoppteknik verkar kunna vara en bidragande faktor för prestation inom klättring. / Rock climbing performed on overhanging surfaces is becoming more common and requires more advanced use of the lower body. Since previous research has mostly examined upper body strength there is a need for a muscular profiling of the lower body of climbers, which was the purpose of this study. The study sought to investigate whether differences in strength and power in the lower extremities can be related to climbing performance in male climbers. The participants were 10 male amateur climbers divided into two groups based on athletes-specific performance level. Group 1 (n=6) where categorized as advanced climbers and group 2 (n=4) as moderate. An isokinetic strength test and two different jump tests were performed by all study participants. After statistical analysis, there were no significant differences (p= 0,05) between the groups in relative strength in the quadriceps, relative strength in hamstrings, H/Q-ratio, jump height at SJ or jump height at CMJ. The group with more advanced climbers performed significantly higher at CMJ versus SJ (p = 0.013). The conclusions of this study are that climbers have relatively low results when measuring H/Q-ratio at 90°/s (group 1: 51% vs. group 2: 53,9%), 210°/s (59,4% vs. 57,9%) and height at vertical jump tests (SJ: 32,1cm vs. 31,7cm; CMJ: 35,8 cm vs. 33,9 cm) and that jump technique seems to be a contributing factor in climbing performance.
43

Habiter autrement : des squats féministes en France et en Allemagne : une remise en question de l'ordre social. / living otherwise : some feminist squats in france and in Germany : questionning of the social order

Gaillard, Edith 11 February 2013 (has links)
Loin d’être homogène, l’habitat est à la fois le reflet de l’assignation des femmes à un rôle de sexe et, dans le même temps, un instrument politique du changement social, de la transgression des normes sociales fixées sur le genre. De quelles manières des actions collectives féministes qui se réclament de l’émancipation peuvent-elles, par le biais de pratiques habitantes, affirmer un autre possible, construire d’autres modes d’être et d’agir en vue d’une vie plus libre ? La mise en œuvre de notre questionnement a conduit à choisir comme objet d’étude le « squat » associé à une critique féministe de l’ordre social. Du squat féministe, un regard se pose sur l’ordre social, un discours est porté sur les raisons de cet engagement dans les marges de la société. Des attitudes, des manières de faire et d’agir s’y construisent afin d’élaborer des réponses à la question des rapports sociaux, des rapports de genre. Nous avons comparé deux modèles de squat féministe : les squats politiques français soumis à une grande instabilité du fait de leur statut « sans droit ni titre » et les squats « légalisés » allemands qui, au regard du contexte historique et politique, s’inscrivent dans un temps plus long. La thèse permet d’élaborer une sociologie du genre renouvelée à partir d’une remise en question de l’ordre social par un engagement féministe autour de pratiques habitantes et de rendre compte de la façon dont des actrices sociales répondent aux problèmes féministes en fabriquant un « autre » modèle. / Far from being homogeneous, the habitat is both a reflection of the relegation of women to the role of sex and, at the same time, a political instrument of social change, of the transgression of social norms of gender. In what ways can feminist collective actions, which claim to be representative of emancipation, affirm another possible, develop other modes of being and acting for a freer life, through inhabitants’ practices? The implementation of our questioning has led us to choose as the object of study the "squat" associated with a feminist critique of the social order.. From the feminist squat, one’s gaze rests on the social order, a speech is focused on the reasons for this engagement in the margins of society. Attitudes, ways of doing and acting, develop to answer the question of social relationships, of gender relationships. We compared two models of feminist squat: in France, political squats which are instable because of their status "without right or title" and in Germany, "legalized" squats which, in terms of historical and political context, are in a longer timeframe.The thesis allows the development of a sociology of gender, from a feminist questioning of the social order around inhabitants’ practices. It also helps to account for how the social actors respond to feminist problems by making an "other" model.
44

Förändrade trafikflöden : - En fallstudie om bränsleförbrukning och CO2 utsläpp vid fördjupning av Flintrännan

Påhlsson, Dennie, Ljung, Carl January 2018 (has links)
Arbetet med att minska sjöfartens miljöpåverkan är något som är högaktuellt och under ständig utveckling. Vid en omdirigering där delar av sjötrafiken från Stora Bält förflyttas till Flintrännan, skulle miljöbelastningen minska regionalt och öka lokalt. Syftet med denna uppsats var att ta reda på hur bränsleförbrukningen förändrades för den del av sjötrafiken som förflyttades till Flintrännan. Genom detta kunde man också se en tendens till hur sjöfartens bidrag till luftföroreningar i Malmö stad kan förväntas förändras. Slutsatserna var att referensfartygen nästan halverade bränsleförbrukningen när dom valde den kortare rutten via Flintrännan framför Stora Bält. Det framkom att sjöfartens totala bidrag till CO2 utsläppen förväntas minska med 60-190 000 ton. Resultatet uppnåddes genom en insamling av trafikflödesdata samt bränsleberäkningar på tre referensfartyg. / Efforts to reduce shipping's environmental impact are something that is highly topical and constantly evolving. At a redirection where parts of the sea traffic from Stora Bält moved to Flintrännan, environmental impact would decrease regionally and increase locally. The purpose of this paper was to find out how the bunker consumption changed for the part of the sea traffic that were moved to Flintrännan. This could also indicate a tendency to change the contribution of shipping to air pollution in Malmö city. The conclusions were that the reference vessels almost halved the bunker consumption when they chose the shorter route via Flintrännan. It was found that shipping's total net contribution to CO2 emissions is expected to decrease by 60-190 000 tons. The result was achieved through a collection of traffic flow data and fuel calculations on three reference vessels.
45

De la dynamique ferroviaire à l’accommodation microstructurale du rail : Contribution des TTS à la réponse tribologique des aciers : Cas du défaut de squat / From railway dynamic to microstructural adaptation of rail : TTS contribution to tribological response of steels : Case of the squat rail defect

Simon, Samuel 17 March 2014 (has links)
Le squat est un défaut de fatigue de contact apparaissant à la surface du rail et dont le mécanisme d’amorçage est mal compris. Afin de pallier ce manque, une analyse tribologique locale de la bande de roulement du rail est mise en oeuvre à proximité d’un squat naissant. Cette caractérisation révèle une anisotropie importante des couches superficielles du rail associée aux développements de Transformations Tribologiques Superficielles. Ces résultats témoignent de conditions de contact roue/rail particulières dans la zone d’étude, notamment d’un niveau d’efforts de cisaillement inhabituel pour une voie en alignement. Dans le but de valider ces observations, plusieurs essais sont effectués. D’une part les conditions de contact roue/rail dans une zone de squats sont mesurées à partir d’un train instrumenté. D’autre part, la réponse tribologique de l’acier à rail à ces conditions de contact est étudiée à travers le suivi régulier d’une zone d’essais soumise à la circulation ferroviaire. Ces essais permettent d’identifier un déséquilibre important des efforts de traction sur les bogies moteurs et des glissements locaux élevés de la roue sur le rail. Différents mécanismes d’amorçage thermo-mécaniques sont alors proposés au sein d’un schéma global de la réponse tribologique de l’acier à rail. / Squats have recently become recognised as one of the major rolling contact fatigue defects in modern railway networks for which there is currently no solution other than preventive grinding operations or costly rail renewal. To better understand the entire damage mechanism of squat, A tribological and metallurgical analysis of the rolling band and the near surface layer was performed close to an incipient squat. This characterization show a significant anisotropy of the rail surface layer associated with developments of Tribological Transformation of Surface. These results reflect some specific wheel/rail contact conditions in this squat area, including an unusual level of shear forces in a straight track. In order to validate this observations, two tests were performed. On the one hand, the contact conditions in a squat area were measured from an instrumented train. On the other hand, the tribological response of the rail steel was studied through regular monitoring of a test site subjected to railway traffic. These tests allow to identify a high imbalance of the traction forces and the presence of local slips at the wheel/rail interface. Several thermomechanical initiation mechanism of squats are then given in a overall diagram of the tribological response of rail steels.
46

Récupération après reconstruction du ligament croisé antérieur et prévention des ruptures : étude biomécanique d'un mouvement pluri-articulaire / Recovery after anterior cruciate ligament reconstruction and injury prevention : biomechanic study of multi-joint movement

Pairot de Fontenay, Benoît 22 October 2014 (has links)
La reconstruction chirurgicale est le traitement préconisé après rupture du Ligament Croisé Antérieur (LCA) chez les patients sportifs. Cette opération est suivie d'une longue période de rééducation et les résultats en termes de reprise du sport et de récidive ne sont pas totalement satisfaisants. Ainsi ce travail s'articule autour de deux objectifs : l'amélioration de la récupération après lésion du LCA et la prévention des primo-ruptures. Dans un premier temps, nous avons évalué les altérations cinématiques et dynamiques présentes chez les patients, lors d'un mouvement de saut, 7 mois après reconstruction du LCA. Les études conduites mettent en évidence des performances plus faibles et des asymétries plus importantes chez les patients, notamment pour le travail mécanique articulaire total. La jambe opérée présente des déficits au niveau du genou, de la hanche et de la cheville sur des paramètres tels que les amplitudes articulaires, les moments et puissances articulaires. Des altérations ont également été retrouvées sur la jambe non-opérée. Elles se traduisent par une modification des angles de la cheville, du genou, et un plus faible moment articulaire total. Dans un deuxième temps, nous nous sommes intéressés aux possibilités de prévention des ruptures du LCA chez les athlètes féminines. Nos résultats démontrent qu'il est possible de détecter et de diminuer les facteurs de risque neuromusculaires, dont le « valgus dynamique », tout en augmentant la performance de saut chez de jeunes basketteuses. En conclusion, l'amélioration des résultats après lésion du LCA requiert, dans le protocole de rééducation et le suivi des patients, une attention particulière à la qualité d'exécution des mouvements pluriarticulaires, sur chacun des deux membres inférieurs. En parallèle, la détection et la prise en charge des facteurs de risque neuromusculaires devraient être systématisées dans les pratiques ou les publics à risque afin de prévenir les ruptures du LCA / Surgical reconstruction is the common treatment after Anterior Cruciate Ligament (ACL) injury in athletes. It usually requires a long period of rehabilitation and the results in terms of return to sport and re-injury rates are not fully satisfactory. The present work has two aims: the enhancement of recovery after ACL tear and the prevention of initial injury. Firstly, we assessed the kinematic and kinetic alterations during a jump task in patients 7 months after ACL reconstruction. Our findings highlight both a lower jumping performance, and greater asymmetries in patients, particularly considering the total joint mechanical work. The operated leg presents deficits at the knee, hip and ankle joints on parameters such as joint range of motion, joint moments and powers. In addition, changes are also found on the non-operated leg, characterized by a modification of the knee and ankle joint angles, and by a lower total joint moment. Secondly, we focused on ACL injury prevention in female athletes. We determinate a way to detect and reduce the neuromuscular risk factors, including “dynamic valgus”, while increasing jumping performance in young basketball female players. In conclusion, maximizing the recovery after ACL tear requires, in the rehabilitation protocol and the patients follow-up, a particular emphasis on the quality of execution of multi-joint task, on each of both lower limbs. Moreover, the detection and management of the neuromuscular risk factors should be systematized in sports or public at risk in order to prevent ACL injury
47

Correlación entre torque isocinético máximo de cuadriceps y potencia de la cadena muscular de la extremidad inferior.

Calderón Martínez, Ximena, Montero Orellana, María José January 2004 (has links)
El propósito de esta investigación fue estudiar la correlación entre el torque isocinético máximo de cuadriceps y la potencia de la cadena muscular involucrada en el squat jump. Treinta y un hombres sanos y no entrenados con una edad promedio de 21.8 +1.03 años fueron sometidos a una medición antropométrica, una prueba de squat jump sobre una plataforma de contacto y una evaluación isocinética de cuadriceps. La potencia se calculó en base a la altura máxima de salto y el peso corporal de cada sujeto. El torque isocinético máximo de cuadriceps se calculó a velocidad angular baja de 60º/s (T60), intermedia de 180º/s (T180) y alta de 2400/s (T240) en una máquina isocinética. Potencia (P) y torque (T60, T180, T240) se expresaron en valores absolutos, en función del peso corporal (Pp, T60p, T180p, T240p) del sujeto y en función de la masa magra del mismo (Pm, T60m, T180m, T240m). El test de Pearson indicó la existencia de una correlación positiva y estadísticamente significativa (p < 0,05) entre P y el torque isocinético máximo, en donde la mayor correlación se encontró entre P y T180 (r = 0.65). En función del peso corporal, las correlaciones fueron menores y la más alta coincidió con T180p (r=0.57). En relación a la masa magra, se encontraron los menores coeficientes de correlación, con una significancia baja para T180m y T240m (r = 0.35 y r = 0.37 respectivamente) o ausente para T60m(r = 0.19). El presente estudio demuestra la existencia de una correlación significativa entre el torque isocinético máximo de cuadriceps y la potencia de la cadena muscular involucrada en el squat jump, en la muestra utilizada en la investigación.
48

Srovnávací studie predikčních rovnic pro výpočet hodnoty 1-RM u dřepu a mrtvého tahu / The comparative study of predication equations for value calculation 1-RM at the squat and the dead lift.

Radovnický, Jiří January 2014 (has links)
Titel: The comparative study of predication equations for value calculation 1-RM at the squat and the dead lift. Aim: To evaluate the most exact equation for the calculation 1-RM on the basis of comparation of extracted data with predication equations at the squat and the dead lift. Research complex: The research complex is created by the soldiers of Army of Czech Republic. They are the men at the age from 20 to 40 with health classification A. Used methods: The comparative method with the using of experimental testing. Results: By the mutual comparation of data we have found out, that the most exact predication equation for the calculation 1-RM in a squat or in a dead lift is from the authors O'Conner et al. Squat was predicted with correlation coefficient r = 0.975 and deadlift with a value of r = 0.951. Keywords: sqaut, dead lift, 1-RM, prediction equation, correlation coefficient.
49

Aktivita svalů dolních končetin při provádění dřepu a techniky seoi nage v judu / Lower limb muscle activity during squat and judo technique seoi nage

Holý, Jakub January 2015 (has links)
Title: Lower limb muscle activity during squat and technique seoi nage in judo Objectives: Goals of my work is finding activity lower muscle limb using surface electromyography in shallow squat, deep squat and seoi nage technic in judo. From the obtained results will be compared muscle activity in relative to MVC and compared timing activity of measuring muscles between deep squat and technic seoi nage right. Methods: Research component consisted of 10 subjects, 5 of fitness and 5 are active judokas. With using surface electromyography and kinematic analysis we monitored activity of measured muscles in shallow and deep squat, and seoi nage technic. The size of muscle activity was assessed in relation to MVC. Results: Evaluation of the results showed a higher involvement by m. gluteus maximus in deep squat than shallow squat. Deep squat makes higher muscles activity. Performing of seoi nage technique resulted in higher values by m. quadriceps femoris. Sequence involvement of muscles during deep squat and seoi nage techniques in selected subjects showed we a strong similarity with various techniques. Key words: Lower limb muscle,judo, electromyography, squat, seoi nage
50

Dinâmica longitudinal : efeitos da geometria de suspensão nas mudanças de atitude da massa suspensa e os esforços nos elementos da suspensão / Longitudinal dynamics : effects of the geometry suspension on the sprung mass attitude and the effort on elements suspensions

Barreto, Marco Antonio Zanussi 27 June 2005 (has links)
Este trabalho tem como objetivo estudar a influência da geometria de suspensão do veículo nas atitudes da massa suspensa. Apresenta um confronto entre obras e autores e está segmentada em três partes; onde na primeira parte são definidos os conceitos básicos como dive, squat, lift, anti-dive, anti-squat, anti-lift e equivalente trailing-arm; na segunda parte são apresentadas as limitações e os novos conceitos definidos por R. S. Sharp e na terceira parte é apresentado o modelo dinâmico bidimensional introduzido por Fu-Cheng Wang. Apresenta um modelo virtual em sistema de multi-corpos desenvolvido no programa ADAMS, com todos os subsistemas que compõe um veículo completo. Inova ao trazer como objeto de estudo um veículo de competição (fórmula SAE) que possui como particularidade o sistema de suspensão push-rod. Surpreende com os resultados obtidos, pois, contrariam os conceitos básicos encontrados na maioria dos livros / This work has objective study the influence of suspension geometry on the sprung mass attitudes. It presents a confrontation among works and authors and this segmented in three parts; where in the first part the basic concepts are defined, dive, squat, lift, anti-dive, anti-squat, anti-lift and equivalent trailing-arm; in the second part the limitations are presented and the new concepts are defined for R. S. Sharp and in the third part are presented the bidimensional dynamic model introduced by Fu-Cheng Wang. It presents a virtual model in system of multi-bodies developed in the program ADAMS, with all the subsystems that composes a complete vehicle. It innovates when bringing such object to study one vehicle of competition (formula SAE) that it has a particularity suspension system push-rod. It surprises with results because it’s opposite of the basic concepts which is present in the majority of books

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