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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.
151

Návrh vybudování sítě bodů podrobného polohového bodového pole jako podklad pro řešení komplexní pozemkové úpravy metodou geodetickou a GPS. / Project and realisation of the network for planimetry control points using the methods geodetic and GPS.

MACH, Václav January 2010 (has links)
This work was elaborated on the theme: Design of building a network of detailed positional point field as a basis for solving complex land treatment method of surveying and GPS. The aim was to assess the current status of position of the point field in the locality, spot field complemented by a focused method of surveying and GPS. Building a network of PPBP served for the implementation of comprehensive land consolidation in the cadastral Chudenín in Klatovy. Reconnaissance of the existing points of positional point field was made based on geospatial data and maps. The area has been designed and stabilized PPBP 9 new items. Focusing was conducted by surveying and GPS. For geodetic positioning targeting method was used electronic total station TOPCON GTS Series - 502 E. Positional orientation points using GPS was carried two-frequency surveying system Promark 500.
152

The extractive sector bureaucracy: An analysis of the high bureaucracy professional profile of the Ministerio de Energía y Minas during the context of the commodity boom (2006-2016). / La burocracia del sector extractivo: Un análisis del perfil profesional de la alta burocracia del Ministerio de Energía y Minas en el marco del boom de los commodities (2006-2016).

Arriola, Addier, Alva, Jair, Calisaya, Stephany, Trujillo, Jimy 12 April 2018 (has links)
This article focuses in the analysis of the high bureaucracy professional profile (ministers, vice ministers and directors) from the Ministerio de Energía y Minas (MINEM) during the context of the so-called commodity boom (2006 – 2016), a period characterized by the sustai- ned rise in the price of raw materials. In order to achieve this objective, we have elaborated a monitoring database picking up demographic characteristics; educational trajectories and career paths; career stability; employment links; and political party ties from 73 top managers of the MINEM organic units that worked in the period from 2006 to 2016. Thus, this research has as objectives to provide a descriptive professional profile of the high bureaucracy of the MINEM during the so-called boom of raw materials and to analyze and discuss their professionalization from a theoretical framework that relates bureaucratic quality to state capacity. / El artículo se centra en el análisis del perfil profesional de la alta burocracia (ministros, viceministros y directores) del Ministerio de Energía y Minas (MINEM) en el contexto del denominado boom de los commodities (2006-2016), un período caracterizado por el alza sost enida del precio de las materias primas. Para cumplir con este objetivo, se elaboró una base de datos de seguimiento y monitoreo, la cual recoge las características demográficas, trayectorias educaciones y líneas de carrera, la estabilidad en la carrera, los vínculos laborales y los vínculos partidarios de los 73 altos directivos de las unidades orgánicas del MINEM que laboraron entre el periodo 2006-2016. Así, la presente investigación tiene como objetivos brindar de manera descriptiva un perfil profesional de la alta burocracia del MINEM durante el denominado boom de las materias primas, y analizar y discutir su profesionalización a partir de un marco teórico que relaciona la calidad burocrática con la capacidad estatal.
153

Análise não linear geométrica de sólidos elásticos tridimensionais reforçados com fibras através do método dos elementos finitos / Geometric nonlinear analysis of fiber reinforced tridimensional elastic solids using finite element method

David de Paulo Pereira 14 December 2015 (has links)
O presente trabalho tem por finalidade estudar e implementar um modelo numérico de análises cinemáticas de sólidos tridimensionais via método dos elementos finitos posicionais, com consideração de fibras longas ou curtas inseridas de maneira aleatória ou não no domínio da análise. O modelo numérico considera material isotrópico para a matriz e não linearidade geométrica. O domínio do sólido é discretizado por meio de elementos finitos tetraédricos de ordem qualquer, cujos parâmetros nodais são suas posições. A medida de deformação utilizada é a de Green, associada à lei constitutiva de Saint-Venant-Kirchhoff, referenciada pela configuração inicial do corpo, caracterizando o sistema de espaço como Lagrangiano total. O cálculo da posição de equilíbrio é baseado no princípio da mínima energia potencial total. Para a resolução do problema não linear geométrico, adota-se o método iterativo de Newton-Raphson. A inserção das fibras no domínio da análise é feita com a associação das mesmas com elementos finitos unidimensionais curvos de ordem qualquer, cujas posições nodais são dadas em função das posições dos nós dos elementos de sólido. Essa abordagem tem como vantagem o fato de não aumentar o número de graus de liberdade do sistema, ao mesmo tempo em que não limita as posições das fibras dentro do domínio por não ser necessária a coincidência das malhas. Exemplos são apresentados para validação dos desenvolvimentos e implementações realizadas. / This study aims to develop and implement a numerical model of kinematic enrichment, to analyze tridimensional solids based on positional finite element method, considering long and short fibers random distributed inside the domain. The numerical model considers isotropic material and geometric nonlinear behavior for both matrix and fibers. Tetrahedral finite elements with any order of approximation are used to discretize the solid domain, with positions as nodal parameters. Green strain and Saint-Venant-Kirchhoff constitutive law are used, referenced in initial configuration of the body, characterizing the developed formulation as total Lagrangian. The equilibrium is obtained with the application of Total Potential Energy Principle, adopting the Newton-Raphson method to solve the resulting nonlinear system of equations. The fibers are considered in the formulation using curved one-dimensional finite elements with any order of approximation, and the nodal positions of the fibers are related with the nodal positions of the solid elements. The coupling method adopted does not increase the number of degrees of freedom of the system, and does not limit the positions of the fiber nodes to be coincident with solid nodes. Examples are presented in order to validate the developed and implemented formulations.
154

Análise elastoplástica bidimensional de meios reforçados com fibras / Bidimensional elastoplastic analysis of fiber reinforced medium

Victor Alves Fernandes 20 April 2016 (has links)
De modo a satisfazer aspectos de resistência, custo ou conforto, o aperfeiçoamento do desempenho das estruturas é uma meta sempre almejada na Engenharia. Melhorias têm sido alcançadas dado ao crescente uso de materiais compósitos, pois estes apresentam propriedades físicas diferenciadas capazes de atender as necessidades de projeto. Associado ao emprego de compósitos, o estudo da plasticidade demonstra uma interessante alternativa para aumentar o desempenho estrutural ao conferir uma capacidade resistente adicional ao conjunto. Entretanto, alguns problemas podem ser encontrados na análise elastoplástica de compósitos, além das próprias dificuldades inerentes à incorporação de fibras na matriz, no caso de compósitos reforçados. A forma na qual um compósito reforçado por fibras e suas fases têm sua representação e simulação é de extrema importância para garantir que os resultados obtidos sejam compatíveis com a realidade. À medida que se desenvolvem modelos mais refinados, surgem problemas referentes ao custo computacional, além da necessidade de compatibilização dos graus de liberdade entre os nós das malhas de elementos finitos da matriz e do reforço, muitas vezes exigindo a coincidência das referidas malhas. O presente trabalho utiliza formulações que permitem a representação de compósitos reforçados com fibras sem que haja a necessidade de coincidência entre malhas. Além disso, este permite a simulação do meio e do reforço em regime elastoplástico com o objetivo de melhor estudar o real comportamento. O modelo constitutivo adotado para a plasticidade é o de von Mises 2D associativo com encruamento linear positivo e a solução deste modelo foi obtida através de um processo iterativo. A formulação de elementos finitos posicional é adotada com descrição Lagrangeana Total e apresenta as posições do corpo no espaço como parâmetros nodais. Com o intuito de averiguar a correta implementação das formulações consideradas, exemplos para validação e apresentação das funcionalidades do código computacional desenvolvido foram analisados. / In order to satisfy strength, cost or comfort aspects, the improvement of the structural performance is a mark always desired in Engineering. Progress has been achieved due to the use of composite materials, because these present different physical properties capable of attending the needs of projects. Associated to the use of composites, the study of plasticity presents an interesting alternative to raise the structural performance by providing an additional resistance capability to the set. However, some problems may be found in the elastoplastic analysis of composites, besides the inherent difficulties of fiber insertion in the matrix, in the case of fiber reinforced composites. The way that the fiber reinforced composite and its phases are represented and simulated are of extreme importance to assure that the obtained results are compatible to the reality. As more refined models are developed, problems arise concerning computational cost and the need of compatibilization of the degrees of freedom between the nodes of the mashes of the matrix and the reinforcement, many times demanding the coincidence of the refered meshes. The present work utilizes formulations that allow the representation of the fiber reinforced composite without the need of mesh coincidence. It also enables the simulation of the medium and the reinforcement at the elastoplastic regime, with the objective study better the real behaviour. The constitutive model for the plasticity adopted is the von Mises 2D associative with a positive linear hardening and the solution of this model was obtained through an iterative procedure. The positional finite element method is adopted with a Total Lagrangean description and uses the positons of the body in space as nodal parameters. With the aim to ensure the correct implementation of the considered formulations, examples for validation and presentation of the functionalities of the developed computacional code were analized.
155

Desenvolvimento e aplicação de código computacional para análise de estruturas de aço aporticadas em situação de incêndio / Development and application of computational code for steel frame analysis in fire situation

Ronaldo Rigobello 17 October 2011 (has links)
O presente trabalho teve por objetivo desenvolver um código computacional com base no método dos elementos finitos, para análises termoestruturais de estruturas de aço aporticadas quando expostas a ações térmicas típicas de situações de incêndio. O código utilizado nas análises estruturais emprega elemento finito de pórtico não linear 3-D de formulação posicional. A formulação posicional utiliza como graus de liberdade as posições dos nós ao invés dos deslocamentos, resultando em uma descrição intrinsecamente não linear do comportamento geométrico das estruturas. Podem ser consideradas seções transversais quaisquer com o elemento finito em questão, e sua representação geral é tridimensional. Adota-se uma lei constitutiva tridimensional completa e a cinemática de Reissner, de modo que o modelo de plasticidade considera o efeito combinado das tensões normais e cisalhantes para verificação do critério 3-D de plasticidade. O código computacional desenvolvido permite que sejam realizadas análises térmicas transientes com base no método dos elementos finitos para se determinar campos de temperatura nas seções transversais dos elementos estruturais sujeitos ao fogo. Assim, a influência da temperatura nas propriedades dos materiais é levada em consideração para se avaliar o desempenho da estrutura em cada instante da análise em situação de incêndio, até que o colapso estrutural seja verificado. Análises de casos presentes na literatura são utilizados para validar os resultados obtidos, os quais comprovam a precisão do código computacional desenvolvido e da formulação posicional quando aplicados a análises de estruturas de aço aporticadas à temperatura ambiente e em situação de incêndio. / The present work deals with the development of a computational code based on the finite element method for thermo-structural analyses of steel framed structures when exposed to typical thermal actions of fire condition. The structural analysis is performed considering a computer code that uses 3-D frame nonlinear finite elements of positional formulation. This formulation is based on the positions of the finite element nodes, instead of displacements, which results in an intrinsically nonlinear description of the geometric behavior of structures. The cross-sections of finite elements can be of any geometry due to the tridimensional representation. A complete tridimensional constitutive law is used and, therefore, the effect of combined normal and shear stresses is taken into account for the tridimensional plasticity evolution. The developed computational code allows performing transient thermal analyses to determine the temperature field over the cross-sections of the structural elements subjected to fire. The influence of temperature on the material properties is considered to evaluate the structure response at each defined instant of the fire analysis, until the collapse occurs. The achieved results, when compared to those found in the literature, allow verifying the precision of the developed computational code when applied to steel frame analysis at ambient temperature and in fire situation.
156

Análise numérica bidimensional de interação fluido-estrutura: uma formulação posicional baseada em elementos finitos e partículas / Two-dimensional fluid-structure interaction numerical analysis: a positional formulation based on finite elements and particles

Giovane Avancini 09 April 2018 (has links)
Problemas envolvendo interação entre fluido e estrutura são desafiadores para a engenharia e, ao mesmo tempo em que abrangem dois meios com características físicas distintas, demandam uma descrição matemática para cada um deles que seja compatível, de forma a permitir o acoplamento. Assim, este trabalho apresenta uma formulação em descrição Lagrangeana para análises dinâmicas de sólidos, fluidos incompressíveis e interação fluido-estrutura (IFE). Nos problemas de IFE é comum a estrutura apresentar grandes deslocamentos, o que torna imprescindível considerar o efeito da não-linearidade geométrica. Levando isso em consideração, é empregada uma formulação do método dos elementos finitos (MEF) baseada em posições, cuja aplicação em análises dinâmicas de estruturas em regime de grandes deslocamentos vem se mostrando bastante robusta. Já no âmbito da dinâmica dos fluidos, sabe-se que uma descrição Lagrangeana acaba por eliminar os termos convectivos das equações de Navier-Stokes, dispensando o uso de métodos estabilizantes nessas equações. Por outro lado, a dificuldade é então transferida para o uso de técnicas eficientes de remesh, preservação da qualidade da malha e de identificação do contorno, uma vez que os fluidos podem deformar-se indefinidamente quando submetidos a forças de cisalhamento. Assim, uma combinação do método dos elementos finitos e do método de partículas é utilizada, onde as forças de interação entre as partículas de fluido são calculadas por meio de uma malha de elementos finitos que é renovada para cada passo de tempo. Por meio de técnicas que reconstroem automaticamente o contorno, é possível simular problemas de superfície livre que sofram severas alterações e, até mesmo, uma eventual separação de partículas do domínio inicial, representando, por exemplo, a formação de gotas. Por fim, o sistema de acoplamento entre o fluido e o sólido é simplificado devido a ambos os domínios serem descritos através de um referencial Lagrangeano, não necessitando de métodos para a adaptação da malha do fluido de modo a acompanhar o movimento da estrutura. / Problems involving fluid-structure interaction are challenging for engineering and, while involving two different materials with distinct physical properties, they require a compatible mathematical description for both solid and fluid domain in order to allow the coupling. Thus, this work introduces a formulation, under Lagrangian description, for the solution of solid, incompressible fluid dynamics and fluid-structure interaction (FSI). In FSI problems, the structure usually presents large displacements thus making mandatory a geometric non-linear analysis. Considering it, we adopt a position based formulation of the finite element method (FEM) which has been shown to be very robust when applied to large displacement solid dynamics. For the fluid mechanics problem it is well known that a Lagrangian description eliminates the convective terms from the Navier-Stokes equations and thus, no stabilization technique is required. However, the difficulty is then transferred to the need of efficient re-meshing, mesh quality and external boundary identification techniques, since the fluid presents no resistance to shear stresses and may deform indefinitely. In this sense, we employ a combination of finite element and particle methods in which the particle interaction forces are computed by mean of a finite element mesh which is re-constructed at every time step. Free surface flows are simulated by a boundary recognition technique enabling large domain distortions or even the particles separation from the main domain, representing for instance a water drop. Finally, the fluid-structure coupling is simplified due to the Lagrangian description adopted for both materials, with no need for extra adaptive mesh-moving technique for the fluid computational domain to follow the structure motion.
157

O globo terrestre e a esfera celeste : uma abordagem interdisciplinar de matemática, geografia e astronomia

USUI, Tetsuo 25 August 2014 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-29T14:39:03Z No. of bitstreams: 1 Tetsuo Usui.pdf: 2577747 bytes, checksum: 9114b8620e50bf459a5b0f41ed172e08 (MD5) / Made available in DSpace on 2017-03-29T14:39:03Z (GMT). No. of bitstreams: 1 Tetsuo Usui.pdf: 2577747 bytes, checksum: 9114b8620e50bf459a5b0f41ed172e08 (MD5) Previous issue date: 2014-08-25 / This work aims to establish a connection among Mathematics with Geography and Astronomy. In this perspective it aims to encompass an interdisciplinary approach in understanding the geographical concepts of the globe, as well as the concepts inherent in the celestial sphere underlying the theoretical foundations of Euclidean Geometry, in order to present a logical and deductive structure of Geometry and Trigonometry in that sphere. This work complements the existing gap between the subjects of Geography and Mathematics in High School because it gives Mathematical supports to the lines (parallels and meridians) and geographic coordinates. Being therefore useful for undergraduate Mathematics students, the same way that teachers of Mathematics and Geography from High School and Elementary Education. Moreover, it also contemplates the sky watchers who wish to have a look at Astronomy from a point of view of Greek antiquity, since the study of Spherical Trigonometry was totally linked to the celestial study. / O presente trabalho tem como objetivo principal estabelecer uma conexão da Matemática com a Geografia e a Astronomia. Nesta perspectiva visa contemplar uma abordagem interdisciplinar na compreensão dos conceitos geográficos do globo terrestre, assim como, dos conceitos inerentes à esfera celeste acoplados na fundamentação teórica de Geometria Euclidiana, a fim de apresentar uma estrutura lógica e dedutiva da geometria e da trigonometria na esfera. O trabalho complementa a lacuna existente entre as disciplinas de Geografia e Matemática do Ensino Médio, pois fundamenta matematicamente, as linhas (paralelos e meridianos) e coordenadas geográficas. Sendo, portanto, útil para alunos de Graduação de Licenciatura em Matemática, da mesma forma que aos professores de Matemática e Geografia do Ensino Médio e Fundamental. Além disso, também contempla aos observadores do céu que queiram olhar a astronomia de um ponto de vista da antiguidade grega, pois o estudo da trigonometria esférica estava totalmente vinculado ao estudo celestial.
158

Formulação de elemento finito posicional para modelagem numérica de pórticos planos constituídos por compósitos laminados: uma abordagem não linear geométrica baseada na teoria Layerwise / Positional finite element formulation for numerical modeling of frames made of laminated composites: a geometric nonlinear approach based on Layerwise theory

Geovanne Viana Nogueira 30 April 2015 (has links)
A análise de compósitos laminados apresenta grandes desafios, pois, diferentemente dos materiais isotrópicos homogêneos, os compósitos laminados são constituídos de materiais heterogêneos e anisotrópicos. Além disso, as distribuições de tensões interlaminares obtidas com as formulações convencionais são descontínuas e imprecisas. Sua melhoria, portanto, é imprescindível para buscar e modelar critérios de falha relacionados às estruturas formadas por compósitos laminados. Diante disso, este trabalho se concentrou no desenvolvimento e implementação computacional de um elemento finito posicional de pórtico plano laminado cuja cinemática é descrita ao longo da espessura do laminado de acordo com a teoria Layerwise. A formulação do elemento considera a não linearidade geométrica, originada pela ocorrência de grandes deslocamentos e rotações, e admite deformações moderadas, em função da lei constitutiva de Saint-Venant-Kirchhoff. O desenvolvimento deste trabalho se iniciou com uma preparação teórica sobre mecânica dos sólidos deformáveis e métodos numéricos para que fossem adquiridos os subsídios teóricos necessários ao desenvolvimento de códigos computacionais, à interpretação dos resultados e à tomada de decisões quando das análises numéricas. A formulação desenvolvida é Lagrangiana total com emprego do método dos elementos finitos baseado em posições. Inicialmente o elemento finito posicional de pórtico plano homogêneo é proposto, uma vez que sua cinemática possibilita uma expansão natural para o caso laminado. Os graus de liberdade são compostos por posições nodais e por vetores generalizados que representam o giro e a variação na altura da seção transversal. A eficiência do elemento é constatada através de análises realizadas em problemas de pórtico sujeitos a grandes deslocamentos e rotações. Os resultados obtidos apresentaram excelente concordância com soluções numéricas e analíticas disponíveis na literatura. Uma expansão natural da cinemática é empregada na formulação do elemento laminado. Os graus de liberdade do elemento são as posições nodais e as componentes de vetores generalizados associados às seções transversais de cada lâmina. Dessa forma, as lâminas têm liberdade para variação de espessura e giro independente das demais, mas com as posições compatibilizadas nas interfaces. Os resultados de análises numéricas realizadas em vários exemplos demonstram a eficiência da formulação proposta, pois as distribuições de deslocamentos e tensões ao longo da espessura do laminado apresentaram excelente concordância com as obtidas a partir de análises numéricas utilizando um elemento finito bidimensional em uma discretização bastante refinada. Os exemplos analisados contemplam problemas com seção laminada fina ou espessa. / The analysis of laminated composites presents challenges because, unlike homogeneous isotropic materials, the laminated composites are made up of heterogeneous and anisotropic materials. Moreover, the distribution of interlaminar stresses obtained with conventional formulations are discontinuous and inaccurate. His improvement is therefore essential to check and modeling failure criteria related to structures formed by laminates. Thus, this work focused on developing and computational implementation of a positional finite element of laminated plane frame whose kinematics is described throughout the thickness of the laminate according to Layerwise theory. The formulation element considers the geometric nonlinearity, caused by the occurrence of large displacements and rotations, and admits moderate deformation, in the constitutive law function of Saint-Venant-Kirchhoff. The development of this work began with a theoretical preparation on mechanics of deformable solids and numerical methods for the acquired of the theoretical support needed for the development of computational codes, interpretation of results and decision-making when of the numerical analyzes. The developed formulation is total Lagrangian with use of the finite element method based on positions. Initially the positional finite element of homogeneous plane frame is proposed, since their kinematic enables a natural expansion for the laminate case. The degrees of freedom are composed of nodal positions and generalized vectors representing the spin and the variation in the height of the cross section. The efficiency of the element is verified through analyzes performed in frame problems subject to large displacements and rotations. The results showed excellent agreement with numerical and analytical solutions available in the literature. A natural expansion of the kinematics is used in the formulation of the laminate element. The degrees of freedom of the element are the nodal positions and components of the generalized vectors associated to cross-sections of each lamina. Thus, the laminas are free for the thickness variation and for independent spin, but with the positions matched in the interfaces. The results of numerical analysis performed in various examples show the effectiveness of the proposed formulation, since the distributions of displacements and stresses through the thickness of the laminate agreed well with those obtained from numerical analysis using a discretization with two-dimensional finite elements in a very refined. The examples discussed include problems with thin or thick laminated section.
159

Physiological- and Socio-Cultural Conditions for Performance in Women's Ice Hockey / Fysiologiska och sociokulturella förutsättningar för prestation inom damishockey

Henriksson, Tommy January 2017 (has links)
Background: The ice hockey community is founded on masculine norms and values, and the hockey rink is often described as “the home of men’s ice hockey”. Despite a growing popularity, women’s ice hockey has low priority in comparison to the men’s game. On top of that, the women’s game does not allow body checking, which makes it deviant from what some see as “the real game of ice hockey”. The checking prohibition causes physiological requirements to differ from the men’s game, and since women are underrepresented in ice hockey research, not much is known regarding the physiological- and socio-cultural conditions of women’s ice hockey. The overall aim of this doctoral thesis is to investigate physiological- and socio-cultural conditions important for performance in women’s ice hockey. Methods: This thesis is unique in terms of the interdisciplinary approach between physiology and gender science, and the inclusion of studies based on both qualitative and quantitative research methods. Qualitative thematic interviews with ice hockey coaches from Sweden, Canada, and the United States were used to explore socio-cultural conditions in relation to performance and sport development (Paper I). Relative age effect (RAE) in relation to maturity status was examined through anthropometric measurements and a player questionnaire (Paper II). Physiological field- and laboratory assessments were used to investigate physiological conditions and performance in female competitive ice hockey players from Sweden (Paper III-IV), and players from Canada (Paper IV). Results: The findings from Paper I suggest that coaches need to maintain a holistic approach to coaching to be able to coordinate and optimize the effects based on available conditions. Socio-cultural conditions, such as structural and financial support, are mentioned as important to support opportunities in women’s ice hockey. Furthermore, the results (Paper I) show that female players in Canada and the United States have superior opportunities compared to female players in Sweden. These advantages are mainly attributed to the support provided by the North American education systems. The findings from Paper II suggest that the relative age effect (RAEs) in women’s hockey are also influenced by socio-cultural conditions. Significant RAE (p<.05) was found for Swedish players born in the third quartile (Q3) and for Canadian player born in the second quartile (Q2). Players born in the fourth quartile (Q4) are significantly (p<.05) underrepresentated in both countries. Players tend to be average or late maturers, but no differences can be found by country or position. The findings from Paper III show that field-based assessments are comparable to laboratory assessments with the purpose of predicting skating performance. The Prediction models accounted for 13.6 % to 42 % (laboratory-based models) and 24.4 to 66.3 % (field-based models) of the variance in skating time. Regardless of assessment method, uni-lateral assessments are superior to bi-lateral assessments. The results support the use of field-based assessments in Paper IV. The findings from Paper IV show various physiological profiles for female Swedish and Canadian players. Swedish players had less body fat (p=.007), more lean mass (p=.005), and greater aerobic fitness measured with the20-meter shuttle run beep test (p=<.001). Canadian players had greater maximal isometric leg strength (p=.026), exhibit a greater running acceleration (p=<.001), performed better in single leg standing long jumps (right leg p=.002, left leg p=.030), and showed better anaerobic endurance (p=.029) on- ice. No significant differences can be found between forwards and defenders. Conclusion: The findings of this study show that physiological- and socio-cultural conditions should both be considered in relation to performance in women’s ice hockey. For example, the various physiological profiles are probably an effect of the different socio-cultural conditions in Sweden and Canada. The Canadian profile may be better adapted to performance in ice hockey, but further research is needed to establish a relationship. Since women’s ice hockey often has somewhat limited resources, this knowledge may help optimize the effect of the available resources, and thus improve performance. Improved performance may have a positive long-term effect on the symbolic view of women’s ice hockey. Women can probably further optimize their physical performance in relation to their current conditions. But for permanent changes to occur, power structures in sport must also change. Women themselves have limited opportunities to affect the dominating gender norms and values in ice hockey. / Bakgrund: Ishockeysamhället är grundat på maskulina normer och värderingar, och hockeyrinken beskrivs ofta som "herrishockeyns hem ". Trots en växande popularitet är damishockey lågt prioriterad i jämförelse med herrishockey. Tacklingar är inte tillåtna i damishockey, vilket gör att den skiljer sig från herrishockey som ofta benämns som "riktig ishockey". Tacklingsförbudet innebär att de fysiologiska kraven förändras gentemot om tacklingar skulle vara tillåtna, och det medför att studier gjorda på herrishockey inte är generaliserbara till damishockey. Eftersom kvinnor är underrepresenterade i ishockeyforskning så saknas det kunskap om de fysiologiska såväl som sociokulturella förutsättningarna inom damishockey. Det övergripande syftet med denna doktorsavhandling är att undersöka fysiologiska och sociokulturella förhållanden som är viktiga för prestation i damishockey. Metod: Denna avhandling är unik när det gäller det tvärvetenskapliga tillvägagångssättet mellan fysiologi och genus, samt att den inkluderar studier gjorda med både kvalitativa och kvantitativa metoder. Kvalitativa tematiska intervjuer med ishockeytränare från Sverige, Kanada och USA användes för att utforska sociokulturella förhållanden i förhållande till prestation och idrottsutveckling (Studie I). Relativ ålderseffekt (RAE) i förhållande till mognadsstatus undersöktes genom antropometriska mätningar och en spelarenkät (Studie II). Fysiologiska fält- och laboratorietester användes för att undersöka fysiologiska förhållanden och prestation hos kvinnliga ishockeyspelare från Sverige (Studie III-IV) samt Kanada (Studie IV). Resultat: Resultaten från Studie I visar att tränare måste försöka ha ett helhetsperspektiv för att kunna samordna resurser och optimera effekterna av dessa utifrån sina förutsättningar. Sociokulturella förhållanden, såsom strukturellt och ekonomiskt stöd, nämns som viktiga faktorer för att skapa utvecklingsmöjligheter inom damishockey. Dessutom visar resultaten (Studie I) att kvinnliga ishockeyspelare i Kanada och USA har överlägsna förutsättningar jämfört med kvinnliga ishockeyspelare i Sverige. Dessa fördelar uppkommer främst på grund av det ekonomiska och strukturella stöd som de nordamerikanska utbildningssystemen bidrar med. Resultaten från Studie II föreslår att även relativ ålderseffekt (RAE) i damishockey påverkas av sociokulturella förhållanden. Signifikant RAE (p <.05) hittades för svenska spelare födda i tredje kvartilen (Q3) och för kanadensiska spelare födda i andra kvartilen (Q2). Spelare födda i fjärde kvartilen (Q4) är signifikant (p <0,05) underrepresenterade i båda länderna. Mognadsstatusen på spelarna uppmättes till medel eller sen utifrån tid för första menstruation, men inga skillnader hittades mellan länderna eller mellan positioner. Resultaten från Studie III visar att fälttester är jämförbara med laboratorietester när syftet är att prediktera skridskoåkningsförmåga. Prediktionsmodellerna förklarade 13.6 % to 42 % (laboratoriebaserade modeller) och 24.4 % to 66.3 % (fältbaserade modeller) av variansen i åktid. Oavsett bedömningsmetod visar sig unilaterala tester överlägsna bilaterala tester att prediktera skridskoåkningsförmåga. Resultaten stöder valet av fälttester i Studie IV. Resultaten från Studie IV visar att de svenska och kanadensiska spelarna hade olika fysiologiska profiler. De svenska spelare hade mindre kroppsfett (p = .007), mer fettfri massa (p = .005) och högre aerob kapacitet mätt genom beeptest (p = <.001). De kanadensiska spelare hade högre maximal isometrisk benstyrka (p = .026), bättre löpacceleration (p = <. 001), bättre hoppkapacitet i stående längdhopp på ett ben (höger ben p = .002, vänster ben p = .030) och högre anaerob uthållighet (p = 0,29) på MRSS. Inga signifikanta skillnader hittades mellan forwards och backar. Slutsats: Resultaten från denna avhandling visar att såväl fysiologiska som sociokulturella förhållanden bör beaktas i förhållande till prestation i damishockey. Till exempel är de olika fysiologiska profilerna troligen en effekt av de olika sociokulturella förhållandena i Sverige och Kanada. Den kanadensiska profilen kan vara bättre anpassad till prestation i ishockey men ytterligare forskning behövs för att fastställa om det finns ett verkligt samband. Eftersom damishockeyn ofta har begränsade resurser kan den här kunskapen bidra till att damlag kan nyttja sina resurser på ett mer effektivt sätt och därmed förbättra sin prestation. En förbättrad prestation skulle kunna ha en positiv effekt på damishockeyns symboliska värde, men för att permanenta förändringar ska uppstå måste maktstrukturerna i sporten också förändras. Kvinnorna själva har begränsade möjligheter att påverka den dominerande könsnormen i ishockey.
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Investigating the level of interdependency between the performance(s) of direct opponent(s) in professional football : a study on teams, positional units and individual players competing in the German Bundesliga

Jamil, Mikael January 2015 (has links)
The purpose of this thesis is to investigate the levels of interdependency (simultaneity) between the performances of two direct opponents in professional football. More specifically, interdependency between performances is investigated at three different levels. Firstly, empirical analyses are conducted in order to assess the levels of interdependency between the performances of two teams in direct competition using team-game observations. Secondly, data on team formations and player starting positions within these formations is utilised in order to uniquely match individual players to a sole opponent on the field of play. Further empirical analyses are then conducted in order to investigate the levels of interdependency at this more isolated individual player level using player-game observations. Finally, an empirical investigation into the levels of interdependency between the performances of a positional unit (defence or attack) and their opposing team (as a collective) is conducted using positional unit-game observations. An exclusive and detailed data set ranging from the 2007-08 season to the 2010-11 season is utilised in order to estimate several production functions for teams, individual players and positional units competing in the German Bundesliga. The results in all empirical analyses confirm that the performance of the opponent is significant. At a team and positional unit level, no evidence is found to suggest that the performances of two direct opponents(s) are interdependent, however the results reveal that the recent past performances of the opponent(s) have a significant linear impact upon the performance of the subject. In particular, relative team form going in to a match is revealed to have a significant impact upon the performance of their opponent. At an individual player level, evidence is found to confirm that the performances of players in direct competition are interdependent thus supporting the sports economics theory of joint production. Specifically, the results reveal that the performances of defenders have a significant and negative impact upon the performances of their opposing attackers.

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