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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.
61

Efeito da aplicação de sobrecarga em saltos horizontais e sprints com e sem mudança de direção sobre o desempenho físico de jogadores de futebol americano / Effects of the resisted horizontal jumps, sprints with and without change of direction on the physical performance in American football players.

Saulo dos Santos Gil 30 January 2014 (has links)
É amplamente aceito que o desempenho físico em modalidades como o futebol americano é dependente da potência muscular. Apesar do exposto, ainda existe uma grande controvérsia com relação à manipulação do treinamento de potência ao longo de um período de preparação competitiva. Apesar de o treinamento de força convencional ser usualmente utilizado para o desenvolvimento da potência, tem-se sugerido que para aumentos adicionais nesta capacidade seja necessário o emprego de estratégias mais específicas do ponto de vista mecânico. Contudo, os papéis da aplicação de sobrecarga em gestos específicos não são claros. Assim, o objetivo do presente estudo foi comparar os efeitos de um protocolo de exercícios específicos envolvendo sprints, descolamentos laterais e saltos sem ou com aplicação de sobrecarga sobre o desempenho da velocidade, agilidade e potência. Vinte e quatro sujeitos foram balanceados e distribuídos aleatoriamente em dois grupos experimentais e realizaram dez semanas de treinamento. Nas quatro primeiras semanas foi realizado um treinamento de força. Após este período, foi realizado um protocolo de treinamento específico realizado sem (grupo S) ou com aplicação de sobrecarga (grupo S+V) por mais seis semanas. O desempenho da força (1RM), potência média (PM) e potência média propulsiva (PMP), o desempenho do salto vertical com (CMJ) e sem (SJ) contra movimento, salto horizontal (SH), a velocidade em 5, 10, 15 e 20m e a agilidade em diferentes testes (teste-T, three-cone drill e pro-agility drill) foram avaliados pré-treinamento e após quatro e dez semanas. Após quatro semanas, uma análise por modelos mistos mostrou aumentos similares em ambos os grupos no desempenho do 1RM, PM30%1RM, 10 e 15m, (p<0,05). Após o período de treinamento específico, ambos os grupos apresentaram aumentos no desempenho do SH e teste-T (p<0,05). Quando observamos o efeito conjunto de todo o programa, ou seja, das dez semanas de treinamento, os grupos mostraram aumentos no 1RM, PM30%1RM, SH e nos três testes de agilidade (p<0,05). Além disso, o grupo S+V demonstrou aumentos no desempenho do SJ, CMJ e no teste de velocidade em 10, 15, e 20m (p<0,05). Adicionalmente, apesar de não terem sido observadas diferenças estatísticas entre os grupos, o grupo S+V apresentou um tamanho do efeito superior em praticamente todas as variáveis dependentes comparado ao grupo S após as dez semanas de treinamento. Assim, é possível sugerir a utilização de um protocolo de treinamento de força seguido por um protocolo específico realizado com sobrecarga adicional quando pretendido aumentar o desempenho em habilidades determinantes para o desempenho físico de jogadores de futebol americano. / Physical performance of American football players depends on the power output. However, there are controversies about the power training manipulation in pre-season periods. Despite the conventional strength training to be wide used to improve power output it has been suggested to additional gains to utilize strategies more specifics of the mechanical point of view. Nevertheless, the effects of the resisted movements are unclear. So, the objective of this study was compared the effects of an exercises protocol involving jumps, lateral displacements and sprints without or with an overload (resisted movement) on speed, agility and power. Twenty four American football players participated of the study and they were balanced and randomly allocated into of two groups. In the first four weeks, it was performed a conventional strength training. Then, it was performed a specific protocol realized without (S group) or with an overload (S+V group) for another six weeks. The maximal strength (1RM), mean power (PM), mean propulsive power (PMP), squat (SJ) and countermovement (CMJ) jump, broad jump (SH), speed at 5, 10, 15 and 20m and agility in three different tests (teste-T, three-cone drill e pro-agility drill) were evaluated before, four and ten weeks of training. A mixed model analysis showed after four weeks of training a similar increase of the 1RM, PM30%1RM, speed at 10 and 15m for both groups (p<0,05). Analyzing specific training period, similar improvements were observed in the SH and teste-T (p<0,05). When analyzing the whole training program (i.e. 10 weeks), an increases at 1RM, PM30%1RM, SH and all the agility tests were observed for both groups. Furthermore, the S+V group showed increases in the SJ, CMJ and speed at 10, 15 and 20m (p<0,05). Additionally, despite not having been observed statistical differences between the groups, the S+V group showed a superior effect size in almost all dependent variables compared to the S group after ten weeks. Therefore, for x improvements of the determinant tasks for physical performance of the American football players is possible to suggest a training program involving strength training followed by a specific training protocol realized with an overload.
62

Effekt av olika stretchmetoder på agility och rörlighet hos elitinnebandyspelare / The effect of different stretching methods on agility and flexibility in elite floorball players

Möller, Malin, Sander, Erik January 2012 (has links)
Bakgrund: I många idrotter såsom innebandy används vanligen statisk stretching (SS) som en del av uppvärmningen i tron om att öka prestation trots att statisk stretching har visat sig ha negativ inverkan på aktiviteter som involverar styrka, power, sprint och agility. Syfte: Syftet med föreliggande studie var att undersöka om olika stretchmetoder SS, dynamisk stretching (DS) och ingen stretching (IS) som en del av uppvärmningen påverkade agility och/eller rörelseomfång (ROM) i hamstring hos manliga innebandyspelare i superelitligan och om en eventuell effekt varade upp till 10 min in i testtillfället. Metod: Vid tre testtillfällen testades de olika stretchmetoderna (SS, DS och IS) efter avslutad uppvärmning. Alla tre stretchmetoderna utfördes vid varje testtillfälle efter randomiserad ordning på tre olika grupper. Agility och rörlighet testades med T-test (s) och passive straight leg raise test (o) vid 0 min, 5 min och 10 min efter avslutad stretching. Totalt 9 testpersoner slutförde studien. Resultat: Vid både 0 min och 5 min efter avslutad stretching noterades bäst tid på T-test (s) efter DS (10,20 ± 0,98 samt 9,92 ± 0,49). Vid 10 min noterades bäst tid efter IS (9,68 ± 0,16). Ingen statistisk signifikant skillnad fanns mellan de olika stretchmetoderna och T-test vid varken 0 min (p = 0,93), 5 min (p = 0,90) eller 10 min (p = 0,29). Vid både 0 min och 5 min efter avslutad stretching gav SS det högsta medelvärdet (o) för ROM (73,56 ± 5,79 samt 71,67 ± 7,12). Vid 10 min gav DS det högsta medelvärdet (73,44 ± 8,75). Ingen statistisk signifikant skillnad fanns heller mellan de olika stretchmetoderna och ROM vid varken 0 min (p = 0,92), 5 min (p = 0,94) eller 10 min (p = 0,71). Slutsats: Resultaten i denna studie saknar statistisk signifikans men visar på en svag trend att SS skulle kunna försämra agility samtidigt som den ökar ROM i hamstring och att prestationsförsämringarna gradvis stagnerar. Emellertid gav både DS och IS likvärdiga eller bättre resultat på T-test i förhållande till SS och med det i åtanke rekommenderas för utförande av SS att förlägga den vid separata tillfällen eller i anslutning med avslutad aktivitet. / Background: In many sports such as floor ball static stretching (SS) is commonly used as part of the warm up to increase performance even though SS has shown to have a negative impact on activities involving strength, power, sprint and agility. Purpose: The purpose of this study was to investigate if different stretching methods SS, dynamic stretching (DS) and no stretching (IS) as a part of the warm up affected agility and/or flexibility (ROM) of the hamstring in male elite floor ball players and if the possible effect lasted up to 10 minutes in the test occasion. Methods: At three different days the different stretching methods (SS, DS and IS) were tested after warm up. The three stretching methods were performed at every test occasion in a randomized order on three different test groups. Agility and flexibility were tested with T-test (s) and passive straight leg raise (o) at 0 min, 5 min and 10 min after warm up. A total of 9 subjects completed the study. Results: At both 0 min and 5 min after completed stretching the best time on T-test (s) was performed after DS (10,20 ± 0,98 and 9,92 ± 0,49). At 10 min the best time was performed after IS (9,68 ± 0,16). No significant difference between the different stretching methods and T-test was found at neither 0 min (p = 0,93), 5 min (p = 0,90) nor 10 min (p = 0,29). At both 0 min and 5 min after completed stretching the highest values on ROM (o) was measured after SS (73,56 ± 5,79 and 71,67 ± 7,12). At 10 min highest value was measured after DS (73,44 ± 8,75 ). No significant difference between the different stretching methods and ROM was found at neither 0 min 0 min (p = 0,92), 5 min (p = 0,94) nor 10 min (p = 0,71). Conclusion: The results of this study lack significance but show a weak trend that SS possibly could impair agility but increase flexibility in hamstring and that the performance impairment gradually stagnates. However both DS and IS gave equal or better results on T-test in comparison to SS and with that in mind SS should be performed at a separate occasion or adjacent to the end of the activity.
63

Les Systèmes d'Information Urbanisés : étude et analyse de leur performance / The urbanization of information systems : study and analyze of their performance

Trabelsi, Leila 14 November 2014 (has links)
L’urbanisation des Systèmes d’Information (SI) est une démarche efficace pour la maîtrise de la complexité de l’organisation. Elle renforce la cohérence du SI et permet de l’aligner sur sa stratégie globale. Elle permet également d’aboutir à l’agilité du SI. Cette démarche présente des avantages considérables comme la réduction des coûts informatiques, un meilleur positionnement dans un environnement concurrentiel et une intégration des innovations technologiques afin de garantir l’évolutivité du SI. Par conséquent, l’inscription d’une entreprise dans un projet de refonte d’un SI devient primordiale. Comprendre le succès des SI est un défi complexe ou une réflexion sur l'évaluation des SI doit être appropriée pour capturer l'ampleur des besoins des utilisateurs et des retombées organisationnelles du SI Urbanisé (SIU). L’objet de ce travail est d’évaluer le succès du SI avant et après une démarche d’urbanisation que nous avons accompagné et modélisé. Cette recherche fournit l’une des premières validations empirique quantitative du le performance des SIU et identifie les dimensions qui agissent sur la perception de l’utilisation et les bénéfices nets du SIU. Le travail constitue une tentative qui ne manque pas d’ambition à la compréhension et l’étude de la dynamique de changement d’un SI existant à un SIU. / The urbanization of Information Systems (IS) is an efficient approach to control the complexity of the organization. It strengthens the coherence of IS and aligns it with the business strategy which allows leading to the agility. This approach has significant advantages such as reducing Information Technologies (IT) costs, enhancing the IS position in a competitive environment and ensuring the scalability and sustainability of the IS through the integration of technological innovations. Owing to these factors, the urbanization is considered as a strategic business decision. Thus, its embedding becomes a necessity in order to improve the IS practice. However, apprehending the IS success is a complex challenge due to the lack of global standard assessment criteria of the Urbanized IS (UIS). Commonly, the IS must be appropriate to satisfy user needs and to generate organizational benefits. In this context, the aim of this work is to introduce conceptual framework that enables the evaluation of the IS success after the embedding of urbanization process. This study provides a quantitative empirical validation of the success of UIS and identifies important aspects that influences the perception of the use and net benefits of UIS. The findings present an exploratory validation of urbanization success. The proposed model for the evaluation of UIS has been empirically tested on survey data. The empirical tests highlight the significant causal relationships between UIS constructs such as Quality and use, User Satisfaction and Net Benefits. This work is an ambition attempt to understand and study of the dynamics of change of the existing IS to an UIS.
64

Vybrané parametry kondiční připravenosti mladých elitních hráčů fotbalu / Selected parameters of fitness assesment of elite young soccer players

Bláža, Lukáš January 2014 (has links)
Title: Selected parameters of fitness assesment of elite young soccer players Objectives: This work identifies selected parameters of the fitness readiness of young elite soccer players. Additionally, we describe terrain motor tests focusing on the metrics of speed, dexterity, and agility, amongst others. Finally, we describe the results of the tests and analyze the speed capabilities and individual indicators by using the motor terrain tests. Methods: Subjects were studied using field testing specific to soccer. Participants were elite soccer players under 16 years old who were in the national selection. The subjects attended a measurement at national level with artificial grass, the standard playing conditions. We investigated the speed capabilities of each player, followed by a statistical evaluation of the results using computer programs. Results: The individuals tested showed very good condition parameters, forming a homogeneous assemblage. An analysis of the players' motor test performances determined their speed abilities. It was found that at single speeds in various sections of a run, which the players achieve during a twenty meter run, the curve of acceleration rises and plateaus as they start to maintain their speed. Keywords: football, youth, tests, speed, agility
65

Leagile model in the avocado supply chain: Case study in huaral, peru

Guzman-Marco, Angelo, Paredes-Robalino, Sebastian, Ramos, Edgar, Sotelo-Raffo, Fernando 01 January 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Avocado exports have increased considerably between 2016 and 2019 in Peru. For this reason, it is important that farmers develop strategies in their supply chain that will generate dwell value for their final product. In response to the above, Supply Chain Management Leagile (SCM Leagile) surface. This supply chain strategy Reduce processes that do not generate value to the product and have to rapid response to the constant change in demand for avocado to the international market. The objective of this paper is present a model of SCM Leagile which can be used by the farmers in various agrifood supply chains.
66

Anatomical Study of the Auditory Region of Arctotherium Tarijense (Ursidae, Tremarctinae), an Extinct Short-Faced Bear From the Pleistocene of South America

Arnaudo, Maria Eugenia, Bona, Paula, Soibelzon, Leopoldo Hector, Schubert, Blaine W. 01 December 2016 (has links)
Here we present the most detailed morphological study of the auditory region of a tremarctinae bear, Arctotherium tarijense Ameghino. In addition, we provide new anatomical information of the Tremarctinae inner ear, such as coplanarity and deviation from orthogonality of the semicircular canals, as an approach to infer the head movements which encountered the extinct forms in locomotion. Based on morphological comparisons, A. tarijense exhibits the following particular features: the cavum tympani presents the highest relative volume compared with other ursids; the processus paraoccipitalis has a foramen that is absent in other tremarctines; there is only one (ventral) recess in the anterior region of the cavum tympani; and the recessus epytimpanicus is the smallest for all ursids studied. In relation to the inner ear, A. tarijense shows the lowest values of orthogonality deviation and highest scores of locomotor agility. Based on this, is possible to make a preliminary proposal that this species had a relative high vestibular sensibility and therefore a better ability to explore different kind of habitats. However, this hypothesis might be contrasted among bears taking into account the orientation of each semicircular canal in a phylogenetic framework.
67

Understanding the Biomechanical Factors in Performing a Pre-planned Versus Reactive Agility Drill

Delaney, Amanda Nicole 26 September 2019 (has links)
No description available.
68

Relationship Between Stabilization, Balance, Athletic Performance and Functional Movement

Ashdown, Susan Christine 08 July 2013 (has links) (PDF)
The purpose of this study was to determine the relationship between the functional movement screen (FMS) and a battery of stabilization, balance, and athletic performance assessments, including time to stabilization (TTS), Davies test (DT), Y-Balance test (YBT), and maximum vertical jump (VJ). Sixty-one healthy individuals (32 males, 29 females; age: 22.4 ± 2.7 yr; height: 174.4 ± 10.4 cm, body mass: 74.0 ± 18.8 kg), successfully performed the FMS and the accompanying comparison tests. Correlations were generated between the FMS and TTS, DT, YBT, and VJ (including both unilateral and bilateral assessments) using the R Project for Statistical Computing, with statistical significance set at p < .001 to minimize alpha inflation. Weak correlations were generated between participants' total FMS score (summed from the 7 FMS assessments) and the TTS-left side (r = -.43; p < 0.001), TTS-right side (r = -.35; p<0.006), DT (r = .54; p < 0.0001), and VJ (r = .33; p = 0.101). Moderately strong correlations were generated between total FMS scores and the YBT-left side (r = .69; p < 0.0001) and YBT-right side (r = .70; p < 0.0001). Similar weak significant correlations were generated when comparing the scores of each individual FMS screen with the TTS, DT, YBT, and VJ. Of these, the highest correlations were between the in-line lunge-left side and the YBT-left side (r = .72; p ≤ 0. 001); the in-line lunge-left side and YBT-right side (r = .75; p ≤ 0.001); the trunk stability push-up and VJ (r = .60; p < 0.0001); and the active straight leg raise-left side and TTS-left side (r = -.46; p < 0.0001). In summary, mostly weak correlations were found between the FMS (involving total or individual scores) and the comparison assessments employed in this study. More rigorous investigations are now warranted to determine the causality of these relationships and how the FMS might be applied to activity of daily living, athletic performance, and injury prevention.
69

Understanding Workforce Agility at NASA Kennedy Space Center

Vazquez, Ledlyne H 01 January 2023 (has links) (PDF)
This study aims to define workforce agility via a literature review and a conducted research survey of the Kennedy Space Center (KSC) Engineering workforce. The survey results will help us determine the workforce agility of the KSC engineering team and understand what has allowed them to transition from the Space Shuttle Program to the new Exploration Ground System (EGS) program. Structural Equation Modeling was used to develop a model of relationships to test the hypotheses. The results show that organizational practices and psychological empowerment significantly support workforce agility. The implications of this study for understanding the characteristics of workforce agility are also discussed.
70

EXPLORATIONS OF COGNITIVE AGILITY:A REAL TIME ADAPTIVE CAPACITY

Good, Darren 04 August 2009 (has links)
No description available.

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